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735 results on '"Department of Earth Sciences [University of Cambridge]"'

1. Authigenic formation of clay minerals in the abyssal North Pacific

Author: Steiner, Zvi, Rae, James W. B., Berelson, William M., Adkins, Jess F., Hou, Yi, Dong, Sijia, Lampronti, Giulio I., Liu, Xuewu, Achterberg, Eric P., Subhas, Adam V., Turchyn, Alexandra V., 2 School of Earth and Environmental Sciences University of St Andrews St Andrews UK, 3 University of Southern California Los Angeles CA USA, 4 Department of Geology and Planetary Sciences California Institute of Technology Pasadena CA USA, 5 Department of Earth Sciences University of Cambridge Cambridge UK, 6 College of Marine Science University of South Florida St. Petersburg Campus St. Petersburg FL USA, 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany, 7 Department of Chemistry Woods Hole Oceanographic Institution Woods Hole MA USA, University of St Andrews. School of Earth & Environmental Sciences, University of St Andrews. Centre for Energy Ethics, University of St Andrews. St Andrews Isotope Geochemistry, Steiner, Z [0000-0002-9584-4956], Rae, JWB [0000-0003-3904-2526], Hou, Y [0000-0002-0846-8615], Dong, S [0000-0002-5811-9333], Achterberg, EP [0000-0002-3061-2767], Subhas, AV [0000-0002-7688-6624], Turchyn, AV [0000-0002-9298-2173], and Apollo - University of Cambridge Repository
Subjects: reverse weathering, Atmospheric Science, Global and Planetary Change, calcium, potassium, DAS, Reverse weathering, ddc:549, Porewater, Strontium, MCP, Potassium, Environmental Chemistry, Clay authigenesis, Calcium, strontium, SDG 14 - Life Below Water, clay authigenesis, porewater, General Environmental Science
Abstract: Present estimates of the biogeochemical cycles of calcium, strontium, and potassium in the ocean reveal large imbalances between known input and output fluxes. Using pore fluid, incubation, and solid sediment data from North Pacific multi‐corer cores we show that, contrary to the common paradigm, the top centimeters of abyssal sediments can be an active site of authigenic precipitation of clay minerals. In this region, clay authigenesis is the dominant sink for potassium and strontium and consumes nearly all calcium released from benthic dissolution of calcium carbonates. These observations support the idea that clay authigenesis occurring over broad regions of the world ocean may be a major buffer for ocean chemistry on the time scale of the ocean overturning circulation, and key to the long‐term stability of Earth's climate., Key Points: North Pacific red clay sediments are a sink for marine calcium, strontium, and potassium. Authigenic formation of clay minerals is prevalent in pelagic sediments throughout the North Pacific. The main mechanism for clay formation is recrystallization of aluminosilicates, neoformation can occur in biogenic silica rich sediments., EC H2020 PRIORITY “Excellent science” H2020 European Research Council http://dx.doi.org/10.13039/100010663, Blavatnik Family Foundation http://dx.doi.org/10.13039/100011643, Isaac Newton Trust http://dx.doi.org/10.13039/501100004815, Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, National Science Foundation http://dx.doi.org/10.13039/100000001, https://doi.pangaea.de/10.1594/PANGAEA.946881
Published: 2022

2. Variability in the Concentration of Lithium in the Indo‐Pacific Ocean

Author: Steiner, Zvi, Landing, William M., Bohlin, Madeleine S., Greaves, Mervyn, Prakash, Satya, Vinayachandran, P. N., Achterberg, Eric P., 2 Department of Earth, Ocean & Atmospheric Science Florida State University Tallahassee FL USA, 3 Department of Earth Sciences Uppsala University Uppsala Sweden, 4 Department of Earth Sciences University of Cambridge Cambridge UK, 5 Indian National Centre for Ocean Information Services Hyderabad India, 6 Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science Bangalore India, 1 GEOMAR Helmholtz Centre for Ocean Research Kiel Kiel Germany, Steiner, Zvi [0000-0002-9584-4956], Landing, William M [0000-0002-7514-3247], Bohlin, Madeleine S [0000-0002-2101-9005], Greaves, Mervyn [0000-0001-8014-8627], Vinayachandran, PN [0000-0002-4915-5455], Achterberg, Eric P [0000-0002-3061-2767], and Apollo - University of Cambridge Repository
Subjects: Atmospheric Science, CRYOSPHERE, Oceanografi, hydrologi och vattenresurser, Marine geochemistry, Li/Na, Oceanography, Hydrology and Water Resources, Environmental Chemistry, Na, 3708 Oceanography, North Pacific, GLOBAL CHANGE, PALEOCEANOGRAPHY, Indian Ocean, General Environmental Science, Global and Planetary Change, Li, OCEANOGRAPHY: BIOLOGICAL AND CHEMICAL, ddc:551, fungi, 37 Earth Sciences, BIOGEOSCIENCES, Biogeochemical cycles, processes, and modeling, Biogeochemistry, Nutrients and nutrient cycling, Marine organic chemistry, GEOTRACES, lithium, Marine inorganic chemistry, Biogeochemical kinetics and reaction modeling, dust, GEOCHEMISTRY, Research Article
Abstract: Lithium has limited biological activity and can readily replace aluminium, magnesium and iron ions in aluminosilicates, making it a proxy for the inorganic silicate cycle and its potential link to the carbon cycle. Data from the North Pacific Ocean, tropical Indian Ocean, Southern Ocean and Red Sea suggest that salinity normalized dissolved lithium concentrations vary by up to 2%–3% in the Indo‐Pacific Ocean. The highest lithium concentrations were measured in surface waters of remote North Pacific and Indian Ocean stations that receive relatively high fluxes of dust. The lowest dissolved lithium concentrations were measured just below the surface mixed layer of the stations with highest surface water concentrations, consistent with removal into freshly forming aluminium rich phases and manganese oxides. In the North Pacific, water from depths >2,000 m is slightly depleted in lithium compared to the initial composition of Antarctic Bottom Water, likely due to uptake of lithium by authigenically forming aluminosilicates. The results of this study suggest that the residence time of lithium in the ocean may be significantly shorter than calculated from riverine and hydrothermal fluxes., Key Points: Li/Na ratios vary by up to 2%–3% in the Indian and Pacific Oceans. Authigenic formation of aluminosilicates slightly deplete deep‐water lithium concentrations in the North Pacific. The residence time of lithium in the ocean is 240,000 ± 70,000 years, based on removal from North Pacific deep‐water., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, MoES, Indian National Centre for Ocean Information Services http://dx.doi.org/10.13039/501100004814, National Science Foundation USA, https://doi.pangaea.de/10.1594/PANGAEA.941888
Published: 2022

3. Annealing of -decay damage in zircon: a Raman spectroscopic study

Author: Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK Laboratoire de Structure et Propri??t??s de l'Etat Solide, B??timent C6, Universit?? Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq, France Department of Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK Mineralogisches Museum, Mineralogisch-Petrographisches Institut, Universit??t Hamburg, Grindelallee 48, D-20146 Hamburg, Germany Department of Nuclear Engineering and Radiological Sciences Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-2104, USA M Zhang Ming Zhang, Ekhard K H Salje, Gian Carlo Capitani, Hugues Leroux, Andrew M Clark, Jochen Schl??ter and Rodney C Ewing, Department of Nuclear Engineering and Radiological Sciences Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-2104, USA, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK, Laboratoire de Structure et Propri??t??s de l'Etat Solide, B??timent C6, Universit?? Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq, France, Department of Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK, Ann Arbor, Zhang, Ming, Salje, Ekhard K. H., Capitani, Gian Carlo, Leroux, Hugues, Clark, Andrew M., Schl??ter, Jochen, Ewing, Rodney C, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK Laboratoire de Structure et Propri??t??s de l'Etat Solide, B??timent C6, Universit?? Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq, France Department of Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK Mineralogisches Museum, Mineralogisch-Petrographisches Institut, Universit??t Hamburg, Grindelallee 48, D-20146 Hamburg, Germany Department of Nuclear Engineering and Radiological Sciences Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-2104, USA M Zhang Ming Zhang, Ekhard K H Salje, Gian Carlo Capitani, Hugues Leroux, Andrew M Clark, Jochen Schl??ter and Rodney C Ewing, Department of Nuclear Engineering and Radiological Sciences Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-2104, USA, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK, Laboratoire de Structure et Propri??t??s de l'Etat Solide, B??timent C6, Universit?? Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq, France, Department of Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK, Ann Arbor, Zhang, Ming, Salje, Ekhard K. H., Capitani, Gian Carlo, Leroux, Hugues, Clark, Andrew M., Schl??ter, Jochen, and Ewing, Rodney C
Abstract: Recrystallization and structural recovery in -decay damage in zircon samples have been studied using Raman spectroscopy. Fifteen zircon samples with different degrees of radiation damage have been thermally annealed between 600 K and 1800 K for up to 28 days and 8 hours. The experimental results from this study reveal that recrystallization in the damaged zircon samples is a multi-stage process that depends on the degree of initial damage of the samples. In partially damaged samples the lattice recovery of damaged crystalline ZrSiO4 takes place at temperatures as low as about 700 K, as shown by a remarkable band-sharpening and a significant increase in the frequencies of 1 and 3 Si-O stretching vibrations together with the external band near 357 cm-1 with increasing temperature. A dramatic increase of Raman scattering intensity of ZrSiO4 occurs in partially damaged samples near 1000 K due to a recrystallization process involving epitaxial growth. Heavily damaged samples tend to decompose into ZrO2 and SiO2 at high temperatures. Tetragonal ZrO2 has been observed under annealing between 1125 K and about 1600 K in heavily damaged samples while monoclinic ZrO2 appears above 1600 K. Weak signals from ZrSiO4 were detected at 1125 K in highly metamict zircon although the main recrystallization appears to occur near 1500 K accompanied by a decrease of the volumes of ZrO2 as well as SiO2 . This suggests that this recrystallization is associated with the reaction of ZrO2 with SiO2 to form ZrSiO4 . A possible intermediate phase has been observed, for the first time, by Raman spectroscopy in damaged zircons annealed at temperatures between 800 K and 1400 K. This phase is characterized by strong, broad Raman signals near 670, 798 and 1175 cm-1 . Prolonged isothermal annealing at 1050 K results in a decrease of these characteristic bands and eventually the disappearance of this intermediate phase.
Published: 2006

4. Alpha-decay damage and recrystallization in zircon: evidence for an intermediate state from infrared spectroscopy

Author: Department of Nuclear Engineering and Radiological Sciences, Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-22104, USA, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK, Mineralogisches Museum, Mineralogisch-Petrographisches Institut, Universit??t Hamburg, Grindelallee 48, D-20146 Hamburg, Germany, Ann Arbor, Zhang, M., Salje, Ekhard K.H., Ewing, Rodney C, Farnan, Ian, R??os, S., Schl??ter, Jochen, Leggo, P., Department of Nuclear Engineering and Radiological Sciences, Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109-22104, USA, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK, Mineralogisches Museum, Mineralogisch-Petrographisches Institut, Universit??t Hamburg, Grindelallee 48, D-20146 Hamburg, Germany, Ann Arbor, Zhang, M., Salje, Ekhard K.H., Ewing, Rodney C, Farnan, Ian, R??os, S., Schl??ter, Jochen, and Leggo, P.
Abstract: ??-decay damage and recrystallization in natural zircon (with dose ranging from 0.06 to 23.3??1018??-events??g -1) were studied using polarized reflection infrared spectroscopy. The experimental results show that??-decay damage leads to a gradual decrease in reflectivity and a loss of anisotropy of IR spectra. Recrystallization of damaged zircon is found as a multi-stage process with a strong dependence on the initial degree of damage. In weakly and moderately damaged samples the major recrystallization takes place near 1000??K. Annealed samples recrystallize epitaxially along their original crystallographic orientations. A highly damaged zircon with radiation dose of 15.9??1018??-events??g -1 decomposes into SiO2 and ZrO2 near 1100??K. In this sample the growth of ZrSiO4 from the binary oxides occurs between 1400 and 1500??K. An additional IR signal peaked near 790??cm -1 is detected in moderately damaged samples annealed at temperatures higher than 800??K. This peak is sharp and isotropic. The peak tends to disappear at temperatures above 1400??K. This signal may be related to an unknown intermediate phase caused by heating of radiation-damaged zircon. Alternatively, the signal may be due to the structural distortions near the boundaries between the amorphized and crystalline regions.
Published: 2006

5. Amorphization in zircon: evidence for direct impact damage

Author: Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109-2104, USA, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK, Ann Arbor, R??os, S., Salje, Ekhard K. H., Zhang, M., Ewing, Rodney C, Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109-2104, USA, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK, Ann Arbor, R??os, S., Salje, Ekhard K. H., Zhang, M., and Ewing, Rodney C
Abstract: X-ray diffraction has been used to characterize the amorphous phase present in a series of radiation-damaged natural zircons with radiation doses ranging from 0.06 to 16 ?? 1018 -decay events g-1 . The fraction of amorphous material present in each of the samples studied has been determined, and its dependence on the radiation dose has been calibrated. Direct determination of the amorphous fraction confirms that amorphization in natural zircon occurs as a consequence of the direct impact within cascades caused by -recoil nuclei. These results are not consistent with the commonly accepted double-overlap model of damage accumulation. The volume swelling of amorphous regions changes as a function of dose. Thus, the density of amorphous regions depends on the degree of damage up to a certain point (i.e. 8 ?? 1018 -decay events g-1 ), unlike in previous models for which a constant value independent of the radiation dose was assumed.
Published: 2006

6. Long-term safety and efficacy of benralizumab in patients with severe, uncontrolled asthma: 1-year results from the BORA phase 3 extension trial

Author: William W Busse, Eugene R Bleecker, J Mark FitzGerald, Gary T Ferguson, Peter Barker, Stephanie Sproule, Richard F Olsson, Ubaldo J Martin, Mitchell Goldman, Anahí Yañez, Marcelo Fernández, Alberto Tolcachier, Juan Belloni, Jorge Taborda, Maria De Salvo, Jorge Maspero, Carlos Victorio, Miguel Chirino Navarta, Monica Grilli, Pablo Rodríguez, María Otaola, Víctor Cambursano, Patricia Malamud, Ana Stok, German Arce, Osiris Roza, Fernando Scherbovsky, Pedro Elias, Maria Salazan Saez, Matthew Peters, Martin Phillips, John Upham, Peter Gibson, Francis Thien, Jo Douglass, Paul Thomas, Philip Bardin, Dimitar Sajkov, Mark Hew, David Langton, Andreia Pez, Carlos Fritscher, Jorge Hetzel, Waldo Mattos, Rafael Stelmach, Martti Antila, Ana Luisa Fernandes, Hristo Metev, Yavor Ivanov, Aneliya Bogdanova, Ana Dancheva Markova, Marinka Peneva, Rumyana Veselinova, Tatyana Petkova, Vanushka Petrova, Elena Shopova, Yuliya Ivanova, Rumyana Yotsova, Ginka Kirkova, Galina Petrova, Svetoslav Dachev, Kostadinka Sotirova, Mariyana Stoyanova, Oleg Yakov, Vanya Ilieva-Fartunova, Catherine Lemiere, Michel Laviolette, William Yang, Bonavuth Pek, William Patrick Killorn, Claude Poirier, Guy Chouinard, Lyle Melenka, Richard Leigh, Parameswaran Nair, Delbert Dorscheid, James Martin, Juana Pavie, Andres Rosenblut, Claudia Cartagena, Carlos Quilodran, Silvia Muñoz, Ivana Malkusova, Josef Veverka, Stanislav Holub, Jaroslav Mares, Radovan Kozel, Daniela Kopecka, Vladimir Zindr, Pavel Cerva, Pascal Chanez, Arnaud Bourdin, Gilles Devouassoux, Camille Taille, Frédéric De Blay, Francois Goupil, Christophe Leroyer, Delphine Gourcerol, Toufik Didi, Alain Didier, Gilles Garcia, Philippe Bonniaud, Riazate Rossanaly Vasram, Marek Lommatzsch, Ulf Harnest, Anneliese Linnhoff, Claus Keller, Gerhard Hoheisel, Karin Förster, Thomas Schultz, Isabelle Schenkenberger, Joachim Kirschner, Tibor Schmoller, Stefan Zielen, Marc Kornmann, Ekkehard Beck, Lutz Volgmann, Rolf Dichmann, Axel Overlack, Jörg Winkler, Petra Mikloweit, Sabine Ballenberger, Mathias Rolke, Stephanie Korn, Helmut Pabel, Martin Hoffmann, Jan Feimer, Klaus Rabe, Regina Deckelmann, Tobias Welte, Hiroyuki Ohbayashi, Soichiro Hozawa, Terufumi Shimoda, Makoto Yoshida, Toshikazu Nagakura, Tadashi Kamei, Yasuyuki Sano, Shinichiro Kagami, Hisaho Takahashi, Michiko Haida, Goro Kimura, Hiroyuki Nakamura, Yasuo To, Masaharu Shinkai, Tadasuke Shimokawaji, Makoto Kudo, Noriharu Shijyubo, Takao Tochigi, Motokazu Kato, Akihiko Tanaka, Yasuhiro Gon, Norihisa Sasaki, Tetsuro Ohdaira, Chiharu Omori, Toshiki Takahashi, Satomi Takeuchi, Kiyotaka Nakajima, Hironi Makita, Masahiro Kaneko, Kenjiro Furuta, Masami Taniguchi, Yoshito Inobe, Hiroshi Miki, Yoichi Nakamura, Naoki Miyazawa, Shuichi Yano, Masayuki Iijima, Tsuyoshi Yamato, Javier Diaz, Alberto Matsuno, Efrain Felix, Alfredo Guerreros, Alejandro Daly, Fernando Rodriguez Chariarse, Danilo Salazar, Socorro Castro, William Chavez, Rolando Estrella, Teresita Aquino, Tito Atienza, Ronnie Samoro, Marie Grace Dawn Isidro, Piotr Kuna, Adam Antczak, Michał Bednarek, Danuta Mądra-Rogacka, Teresa Hofman, Marek Jutel, Ewa Pisarczyk-Bogacka, Agata Kot, Robert Mróz, Małgorzata Czupryńska-Borkowska, Małgorzata Żurowska-Gębala, Andrzej Dyczek, Grażyna Jasieniak-Pinis, Piotr Wojnowski, Ewa Trębas-Pietraś, Małgorzata Dobryniewska, Marcin Stobiecki, Marzenna Tarnowska-Matusiak, Alina Magner, Andrzej Kolczyński, Tomasz Kachel, Zbigniew Bartuzi, Bernadetta Majorek-Olechowska, Paweł Śliwiński, Violetta Balicka, Elżbieta Hajoł, Jacek Stachera, Marta Rachel, Marek Michnar, Jarosław Tałałaj, Ewa Springer, Piotr Napora, Tomasz Grzelewski, Renata Bijata-Bronisz, Anna Świderska, Grzegorz Mincewicz, Zbigniew Sankowski, Tomasz Fijołek, Artur Kwaśniewski, Joanna Jerzyńska, Jerzy Cygler, Ryszard Olesiejuk, Iwona Von Steiner, Wojciech Machowiak, Krzysztof Filipek, Piotr Piskorz, Ewa Uhryn, Marita Nittner-Marszalska, Elżbieta Rybicka-Liszewska, Anna Bodzenta-Łukaszyk, Marta Chełmińska, Izabella Krupa-Borek, Wojciech Skucha, Anna Płoszczuk, Traian Mihaescu, Ioan Dorin Petrui, Angelica Savu, Ghiulten Apti, Claudia Toma, Ana Trailescu, Sergei Sokurenko, Vasiliy Trofimov, Igor Leshchenko, Natalia Shaporova, Inna Ilyashevich, Irina Stitsenko, Alexander Vizel, Yulia Ilkovich, Dmitrii Tikhanov, Svetlana Goncharova, Andrey Ezhov, Galina Ignatova, Nadezhda Izmozherova, Nadezhda Berdnikova, Ludmila Goryachkina, Veronika Popova, Laura Bolieva, Andrey Rebrov, Vladimir Nosov, Olga Magnitskaya, Sergey Nedogoda, Vladimir Abrosimov, Artem Molotkov, Galina Reshedko, Mikhail Smirnov, Marina Osipenko, Elena Pavlysh, Svetlana Myasoedova, Liudmila Lenskaya, Valery Chistyakov, Elena Vishneva, Liliya Uon, Anna Zateyschikova, Svetlana Laleko, Tatiana Pak, Axel Bruning, Visvakuren Naidoo, Jeevren Reddy, Richard Van Zyl Smit, Hae-Sim Park, Young Joo Cho, Sang-Heon Cho, Sang Haak Lee, Byung Jae Lee, Ju Sang Kim, You Sook Cho, Choon-Sik Park, Mi-Kyeong Kim, Young-Il Koh, Joo-Hee Kim, Sook Young Lee, Sang Pyo Lee, Jung Won Park, Kwang Ha Yoo, Hyoungkyu Yoon, Jaechun Lee, Gyu-Young Hur, Soo Keol Lee, HeeKyoo Kim, David Ramos Barbón, Elena Laffond Yges, Eva Martínez Moragón, Miguel Arias Guillen, Alberto Saura Vinuesa, Fernando Sánchez-Toril López, José Luis Velasco Garrido, Borja García-Cosio Piqueras, Luis Pérez de Llano, Antonio Luis Valero Santiago, Myriam Calle Rubio, Leif Bjermer, Bo Lundbäck, Bilun Gemicioglu, Sevim Bavbek, Dane Ediger, Munevver Erdinc, Ismail Hanta, Sibel Nayci, Sibel Arinc, Liudmyla Iashyna, Yuriy Mostovoy, Mykola Ostrovskyy, Lesia Kuryk, Ivan Lemko, Tetyana Ospanova, Liubov Moskalenko, Oleksii Korzh, Viktor Blazhko, Olena Krakhmalova, Liliia Romaniuk, Yevgeniya Dytyatkovs'ka, Oleh Yakovenko, Volodymyr Gavrysyuk, Hassan Burhan, Dinesh Saralaya, Stephen Scott, Alyn Morice, Ewart Jackson-Voyzey, Thida Win, Shuab Nasser, Richard Harrison, Rekha Chaudhuri, Monica Nordstrom, Pradip De, Matthew Masoli, Adel Mansur, Anthony Gunstone, Robert Niven, Timothy Harrison, Suresh Babu, Subodh Bhuchar, Shahrukh Kureishy, John Zwetchkenbaum, Lawrence Kaplan, Eugene Bleecker, Santiago Reyes, Faisal Fakih, Marvin Heuer, Ryan Klein, Michael Marcus, Iftikhar Hussain, Tonny Tanus, Hengameh Raissy, Sady Alpizar, Hector Rodriguez, Gerald Gleich, Tracy Bridges, Joe Pouzar, Gary Steven, Jonathan Matz, Shana Krstevska, Dama Ziworitin, Adolfo Kaplan, James Sublett, James DeAngelo, Amy Darter, John Agaiby, John Hagan, Enrique Davis, Dareen Siri, Charlene Mcevoy, Chrisette Dharma, Najmuddin Karimjee, Steven Kelsen, Manuel Frade, Amy Silverthorn, Joel Kline, Francis Averill, Jose Ruiz, Emory Robinette, Zeeshan Shaikh, Carlos Aguilar, William Nish, German Alvarez, Younus Ismail, Purvi Parikh, Mila Leong, Dennis Murphy, Francisco Garcia, Alan Goldsobel, Antonio Blanco, Edward Campbell, Guido Perez, Geoffrey Chupp, Toby Bates, Vandely Perez, Sally Wenzel, Kartik Shenoy, Rohit Katial, David Bernstein, Neil Parikh, William Sims, Gary Ferguson, David Pham, Anu George, Richard Beasley, Gilberto Perez, Robert Garver, Miriam Garcia-Portela, Stephen Wong, Weily Soong, Richard Guillot, Golda Hudes, Ahmed Arif, Josefa Binker, Manuel Villareal, Ulrike Ziegner, Joseph Ojile, Sanjeev Goswami, Carlos Piniella, Ilia Segal, Heidi Zafra, Mitchell Lee, Martha Tarpay, John Panuto, Rajan Merchant, Peter Springsteen, Timothy Scialla, Paul Shapero, Karen Allen, Mark Moss, Humberto Cruz, Jeffrey Rumbyrt, Amy Boyd, Robert Nathan, Jonathan Bernstein, Joshua Jacobs, Elliot Ginchansky, Janice Johnston, Barbara Baxter, Thomas Johnson II, Stephen Apaliski, Clinton Corder, David Fuentes, Joseph Diaz, Chau Ngo, Lan Le, Department of Medicine, University of Wisconsin-Madison-School of Medicine and Public Health, Fundación Cidea Allergy and Respiratory Research Unit, University of Oxford [Oxford], University of Newcastle, Newcastle, NSW Australia., Defence Science and Technology Laboratory (Dstl), Ministry of Defence (UK) (MOD), Organização Multinacional de Formação, Agence Universitaire de la Francophonie (AUF), University of Calgary, Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research (C2VN), Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Physiologie & médecine expérimentale du Cœur et des Muscles [U 1046] (PhyMedExp), Université de Montpellier (UM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier), laboratoire du sommeil, CHU Grenoble, Physiopathologie et Epidémiologie des Maladies Respiratoires (PHERE (UMR_S_1152 / U1152)), Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM), CHU Strasbourg, Centre Hospitalier du Mans, Groupe d'Etude de la Thrombose de Bretagne Occidentale (GETBO), Université de Brest (UBO)-Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)-Université de Brest (UBO), CIC Brest, Université de Brest (UBO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Hôpital de la Cavale Blanche, Service de pneumologie, Centre hospitalier de la région d'Annecy, Cytokines, chimiokines et immunopathologie, Université Paris-Sud - Paris 11 (UP11)-IFR13-Institut National de la Santé et de la Recherche Médicale (INSERM), J.W. Goethe Universität, Institut für Geowissenschaften, Altenhöferallee 1, D-60438 Frankfurt am Main, Germany, Department of Pulmonary Medicine, Leiden University Medical Center (LUMC), Hannover Medical School [Hannover] (MHH), Japan Energy Corporation, Medical University of Łódź (MUL), Wroclaw Medical University, Saint-Petersburg State University, Physical Department, Petrodvoretz, 194508 St.-Petersburg, Russia, Physical Department (PD), St Petersburg State University (SPbU)-St Petersburg State University (SPbU), Ankara University, Oak Ridge National Laboratory [Oak Ridge] (ORNL), UT-Battelle, LLC, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Center for Genomics and Personalized Medicine, Wake Forest University, Mayo Clinic [Rochester], Department of Wildlife Management, Pir Mehr Ali Shah Arid Agriculture University, Lab Biotecnol Bacteriana, Inst Ciencia & Tecnol Alimentos & Nutr ICTAN, Universidade da Coruña, Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)-Université de Brest (UBO)-Université de Brest (UBO), Centre recherche en CardioVasculaire et Nutrition (C2VN), Université de Brest (UBO), University of Oxford, University of Newcastle [Callaghan, Australia] (UoN), Université de Brest (UBO)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut Brestois Santé Agro Matière (IBSAM), Universiteit Leiden-Universiteit Leiden, Wrocław Medical University, Department of Earth Sciences [University of Cambridge], and Pir Mehr Ali Shah Arid Agriculture University = PMAS-Arid Agriculture University Rawalpindi (AAUR)
Subjects: Adult, Male, Pulmonary and Respiratory Medicine, medicine.medical_specialty, Adolescent, [SDV]Life Sciences [q-bio], Antibodies, Monoclonal, Humanized, Placebo, [SDV.MHEP.PSR]Life Sciences [q-bio]/Human health and pathology/Pulmonology and respiratory tract, Time, law.invention, Young Adult, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, Double-Blind Method, Randomized controlled trial, law, Internal medicine, Clinical endpoint, Humans, Medicine, Anti-Asthmatic Agents, 030212 general & internal medicine, Child, Adverse effect, ComputingMilieux_MISCELLANEOUS, Aged, Asthma, business.industry, Middle Aged, medicine.disease, Benralizumab, 3. Good health, Clinical trial, Treatment Outcome, 030228 respiratory system, Tolerability, chemistry, Female, business, [SDV.MHEP]Life Sciences [q-bio]/Human health and pathology, Follow-Up Studies
Abstract: Benralizumab is an interleukin-5 receptor α-directed cytolytic monoclonal antibody that has been shown to safely reduce exacerbations and improve lung function for patients with asthma. We assessed the long-term safety and efficacy of benralizumab for patients with severe, uncontrolled eosinophilic asthma.We conducted a randomised, double-blind, parallel-group, phase 3 extension study at 447 sites in 24 countries. Eligible patients had to have completed the SIROCCO or CALIMA trials and remained on subcutaneous benralizumab 30 mg every 4 weeks (Q4W) or every 8 weeks (Q8W). Patients who had received placebo in those trials were re-randomised in a 1:1 ratio, using an interactive web-based system, to benralizumab 30 mg either Q4W or Q8W (first three doses 4 weeks apart). Treatment lasted for 56 weeks for adult patients (age ≥18 years) and 108 weeks for adolescent patients (age 12-17 years). The primary endpoint was the safety and tolerability of the two dosing regimens of benralizumab up to 68 weeks for adult patients (including the follow-up visit post-treatment) and up to 56 weeks for adolescent patients. This endpoint was assessed in the full analysis set, which included all patients from the SIROCCO and CALIMA predecessor studies who received at least one dose of study treatment in BORA and did not continue into another trial. This study is registered with ClinicalTrials.gov (NCT02258542).Between Nov 19, 2014, and July 6, 2016, we enrolled 1926 patients, of whom 633 had received benralizumab Q4W and 639 had received benralizumab Q8W in SIROCCO or CALIMA. The remaining 654 patients had received placebo in those trials and were randomly re-assigned in this trial to receive benralizumab Q4W (n=320) or Q8W (n=334). 1576 patients, including 783 who received benralizumab Q4W (265 newly assigned) and 793 who received benralizumab Q8W (281 newly assigned), were included in the full analysis set. The most common adverse events in all groups were viral upper respiratory tract infection (14-16%) and worsening asthma (7-10%). The most common serious adverse events were worsening asthma (3-4%), pneumonia (1% to 1%), and pneumonia caused by bacterial infection (0-1%). The percentages of patients who had any on-treatment adverse event, any serious adverse event, or any adverse event leading to treatment discontinuation during BORA were similar between patients originally assigned benralizumab and those originally assigned placebo and between benralizumab treatment regimens. The percentage of patients who had any adverse event was similar between SIROCCO or CALIMA (71-75%; benralizumab group only) and BORA (65-71%), as was the percentage of patients who had an adverse event that led to treatment discontinuation (2% in SIROCCO and CALIMA vs 2-3% in BORA).The 2 years of safety results validate that observations observed in the first year of benralizumab continued through a second year of treatment. No new consequences of long-term eosinophil depletion occurred, and the incidence of other adverse events, including opportunistic infections, were similar during the second year.AstraZeneca and Kyowa Hakko Kirin.
Published: 2019
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7. Criticality of metals and metalloids

Author: Nedal T. Nassar, Thomas E. Graedel, Philip Nuss, E. M. Harper, Barbara K. Reck, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Université Pierre et Marie Curie - Paris 6 (UPMC), and Department of Earth Sciences [University of Cambridge]
Subjects: Multidisciplinary, Materials science, Waste management, [CHIM.ORGA]Chemical Sciences/Organic chemistry, Environmental engineering, Supply and demand, Material criticality, Metal, Criticality, visual_art, Physical Sciences, visual_art.visual_art_medium, Metalloid, Political instability, ComputingMilieux_MISCELLANEOUS
Abstract: Imbalances between metal supply and demand, real or anticipated, have inspired the concept of metal criticality. We here characterize the criticality of 62 metals and metalloids in a 3D "criticality space" consisting of supply risk, environmental implications, and vulnerability to supply restriction. Contributing factors that lead to extreme values include high geopolitical concentration of primary production, lack of available suitable substitutes, and political instability. The results show that the limitations for many metals important in emerging electronics (e.g., gallium and selenium) are largely those related to supply risk; those of platinum group metals, gold, and mercury, to environmental implications; and steel alloying elements (e.g., chromium and niobium) as well as elements used in high-temperature alloys (e.g., tungsten and molybdenum), to vulnerability to supply restriction. The metals of most concern tend to be those available largely or entirely as byproducts, used in small quantities for highly specialized applications, and possessing no effective substitutes.
Published: 2015
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8. Control of surface potential at polar domain walls in a nonpolar oxide

Author: Claire Mathieu, Jens Kreisel, D. Martinotti, Ludovic Tortech, Ekhard K. H. Salje, Pierre-Yves Hicher, Mael Guennou, Guillaume F. Nataf, Raphael Haumont, Nick Barrett, Oktay Aktas, Laboratoire d'Etude des NanoStructures et Imagerie de Surface (LENSIS), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Luxembourg Institute of Science and Technology (LIST), Physics and Materials Science Research Unit, University of Luxemburg, Laboratoire de Physico-Chimie de l'Etat Solide (CHIMSOL), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences [University of Cambridge], University of Cambridge [UK] (CAM), Laboratoire Innovation en Chimie des Surfaces et NanoSciences (LICSEN UMR 3685), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electronique et nanoPhotonique Organique (LEPO), Nataf, Guillaume [0000-0001-9215-4717], Salje, Ekhard [0000-0002-8781-6154], Apollo - University of Cambridge Repository, Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Department of Earth Sciences, University of Cambridge, Laboratoire Innovation en Chimie des Surfaces et NanoSciences (LICSEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)
Subjects: Materials science, Physics and Astronomy (miscellaneous), FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Condensed Matter::Materials Science, chemistry.chemical_compound, Electric field, 0103 physical sciences, Microelectronics, General Materials Science, 010306 general physics, [PHYS]Physics [physics], Condensed Matter - Materials Science, Condensed matter physics, business.industry, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Polarization (waves), Ferroelectricity, Piezoelectricity, cond-mat.mtrl-sci, Calcium titanate, Ferromagnetism, chemistry, Polar, 0210 nano-technology, business
Abstract: Ferroic domain walls could play an important role in microelectronics, given their nanometric size and often distinct functional properties. Until now, devices and device concepts were mostly based on mobile domain walls in ferromagnetic and ferroelectric materials. A less explored path is to make use of polar domain walls in nonpolar ferroelastic materials. Indeed, while the polar character of ferroelastic domain walls has been demonstrated, polarization control has been elusive. Here, we report evidence for the electrostatic signature of the domain-wall polarization in nonpolar calcium titanate (CaTiO3). Macroscopic mechanical resonances excited by an ac electric field are observed as a signature of a piezoelectric response caused by polar walls. On the microscopic scale, the polarization in domain walls modifies the local surface potential of the sample. Through imaging of surface potential variations, we show that the potential at the domain wall can be controlled by electron injection. This could enable devices based on nondestructive information readout of surface potential., Comment: 30 pages, 12 figures
Published: 2017
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9. The DeepMIP contribution to PMIP4: experimental design for model simulations of the EECO, PETM, and pre-PETM (version 1.0)

Author: Matthew Huber, James C Zachos, Paul Nicholas Pearson, Bridget S. Wade, Bette L. Otto-Bliesner, Sandy Kirtland Turner, Yannick Donnadieu, Allegra N. LeGrande, Reinhardt Kozdon, Petra Langebroek, Arne M.E. Winguth, Anna von der Heydt, Christine A. Shields, Paul J. Markwick, Michael Starz, Garland R. Upchurch, Srinath Krishnan, Scott L. Wing, Jean-Baptiste Ladant, Caroline H Lear, Kathryn E. Snell, Ran Feng, Richard E. Zeebe, Nicky M. Wright, Gregory J. L. Tourte, Edward Gasson, Henk A. Dijkstra, Rodrigo Caballero, Christopher J. Hollis, Jessica E. Tierney, Kate Littler, Michiel Baatsen, Robert L. Korty, Jeff Kiehl, Gordon N. Inglis, Aradhna Tripati, S. M. Jones, Eleni Anagnostou, James R Super, Clay R. Tabor, Gavin L. Foster, Rob DeConto, Ulrich Salzmann, Daniel J. Lunt, David Evans, Christopher J. Poulsen, School of Geographical Sciences [Bristol], University of Bristol [Bristol], Institute for Marine and Atmospheric Research [Utrecht] (IMAU), Utrecht University [Utrecht], Department of Meteorology [Stockholm] (MISU), Stockholm University, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation du climat (CLIM), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Aston University [Birmingham], University of Nottingham, UK (UON), NASA Goddard Space Flight Center (GSFC), Camborne School of Mines, College of Engineering, Mathematics and Physical Sciences, University of Exeter, National Center for Atmospheric Research [Boulder] (NCAR), Archäobotanik Afrikas, Goethe-Universität Frankfurt am Main, University of Arizona, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences [University of Cambridge], and University of St Andrews. Earth and Environmental Sciences
Subjects: Solar constant, 010504 meteorology & atmospheric sciences, Meteorology, Climate change, Earth and Planetary Sciences(all), Forcing (mathematics), 010502 geochemistry & geophysics, 01 natural sciences, Modelling and Simulation, Paleoclimatology, G1, SDG 13 - Climate Action, QE, QA Mathematics, Greenhouse effect, QA, Palaeogeography, ComputingMilieux_MISCELLANEOUS, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, GE, lcsh:QE1-996.5, G Geography (General), DAS, lcsh:Geology, Climate Action, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Paleoclimate Modelling Intercomparison Project, Climatology, Earth Sciences, Climate model, [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology, Geology, GE Environmental Sciences
Abstract: We thank NERC grant NE/N006828/1 for providing funds for the first DeepMIP meeting in Boulder, Colorado, USA, in January 2016. Daniel J. Lunt acknowledges the NERC grant “Cretaceous–Paleocene–Eocene: Exploring Climate and Climate Sensitivity” (NE/K014757/1), and advanced ERC grant “The Greenhouse Earth System” (T-GRES, project reference 340923), awarded to Rich Pancost. Matthew Huber acknowledges funding from NSF OCE-0902882. Michiel L. J. Baatsen, Henk A. Dijkstra, and Anna S. von der Heydt acknowledge support by the Netherlands Earth System Science Centre (NESSC), financially supported by the Ministry of Education, Culture and Science (OCW), 024.002.001. Past warm periods provide an opportunity to evaluate climate models under extreme forcing scenarios, in particular high (> 800ppmv) atmospheric CO2 concentrations. Although a post hoc intercomparison of Eocene (∼ 50 Ma) climate model simulations and geological data has been carried out previously, models of past high-CO2 periods have never been evaluated in a consistent framework. Here, we present an experimental design for climate model simulations of three warm periods within the early Eocene and the latest Paleocene (the EECO, PETM, and pre-PETM). Together with the CMIP6 pre-industrial control and abrupt 4 × CO2 simulations, and additional sensitivity studies, these form the first phase of DeepMIP-the Deep-time Model Intercomparison Project, itself a group within the wider Paleoclimate Modelling Intercomparison Project (PMIP). The experimental design specifies and provides guidance on boundary conditions associated with palaeogeography, greenhouse gases, astronomical configuration, solar constant, land surface processes, and aerosols. Initial conditions, simulation length, and output variables are also specified. Finally, we explain how the geological data sets, which will be used to evaluate the simulations, will be developed. Publisher PDF
Published: 2017
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10. Neo-Tethys geodynamics and mantle convection: from extension to compression in Africa and a conceptual model for obduction

Author: Philippe Agard, Claudio Faccenna, Pietro Sternai, Laurent Jolivet, Armel Menant, Dominique Frizon de Lamotte, François Guillocheau, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Géodynamique - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Earth Sciences, University of Roma TRE, Università degli Studi Roma Tre = Roma Tre University (ROMA TRE), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Université de Cergy Pontoise (UCP), Université Paris-Seine, Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences [University of Cambridge], University of Cambridge [UK] (CAM), Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), European Project: 290864,EC:FP7:ERC,ERC-2011-ADG_20110209,RHEOLITH(2012), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Roma Tre University, Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-TOTAL FINA ELF, Department of Earth Sciences, University of Cambridge, Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES), Polat, A., Jolivet, L, Faccenna, C, Agard, P, Lamotte, D, Menant, A, Sternai, P, Guillocheau, F, Jolivet, Laurent, Faccenna, Claudio, Agard, Philippe, Lamotte, Dominique Frizon De, Menant, Armel, Sternai, Pietro, and Guillocheau, François
Subjects: 010504 meteorology & atmospheric sciences, Subduction, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Geophysics, Geodynamics, 010502 geochemistry & geophysics, Ophiolite, 01 natural sciences, Mantle (geology), Obduction, African Plate, Paleontology, Mantle convection, [SDU]Sciences of the Universe [physics], Transition zone, General Earth and Planetary Sciences, Earth and Planetary Sciences (all), Geology, 0105 earth and related environmental sciences
Abstract: International audience; Since the Mesozoic, Africa has been under extension with shorter periods of compression associated with obductionof ophiolites on its northern margin. Less frequent than “normal” subduction, obduction is a first order process that remainsenigmatic. The closure of the Neo-Tethys Ocean, by the Upper Cretaceous, is characterized by a major obduction event, from theMediterranean region to the Himalayas, best represented around the Arabian Plate, from Cyprus to Oman. These ophiolites wereall emplaced in a short time window in the Late Cretaceous, from 100 to 75 Ma, on the northern margin of Africa, in a contextof compression over large parts of Africa and Europe, across the convergence zone. The scale of this process requires anexplanation at the scale of several thousands of kilometres along strike, thus probably involving a large part of the convectingmantle. We suggest that alternating extension and compression in Africa could be explained by switching convection regimes.The extensional situation would correspond to steady-state whole-mantle convection, Africa being carried northward by alarge-scale conveyor belt, while compression and obduction would occur when the African slab penetrates the upper–lowermantle transition zone and the African plate accelerates due to increasing plume activity, until full penetration of the Tethys slabin the lower mantle across the 660 km transition zone during a 25 Myr long period. The long-term geological archives on whichsuch scenarios are founded can provide independent time constraints for testing numerical models of mantle convection andslab–plume interactions.; Depuis le Mésozoïque, l’Afrique a été en extension avec de courtes périodes de compression associées a`l’obduction d’ophiolites sur sa marge nord. Moins fréquente que la subduction, l’obduction est néanmoins un phénomènede premier ordre qui reste énigmatique. La fermeture de la Neo-Téthys au Crétacé supérieur est caractérisée par un épisodemajeur d’obduction, depuis la Méditerranée jusqu’a` l’Himalaya, en particulier sur la marge de l’Arabie, de Chypre a` l’Oman.Ces ophiolites furent toutes mises en place dans un court laps de temps pendant le Crétacé supérieur, de 100 a` 75 Ma, dansun contexte de compression enregistré en de larges portions de l’Afrique et de l’Europe, au travers de la zone de convergence.L’échelle de ce processus requiert une explication a` l’échelle de plusieurs milliers de kilomètres et donc impliquantvraisemblablement l’ensemble du manteau convectif. Nous suggérons que l’alternance de périodes extensives et compressivesen Afrique résulte de changements du régime convectif. Les périodes extensives correspondraient a` la convectionimpliquant tout le manteau, l’Afrique étant portée par une grande cellule de type tapis-roulant, tandis que la compressionet l’obduction se produiraient quand le panneau plongeant africain pénètre la transition entre le manteau supérieur et lemanteau inférieur et quand la plaque Afrique accélère en conséquence d’une plus grande activité du panache, jusqu’a`pénétration complète, durant une période d’environ 25 Myr. Les archives géologiques sur lesquelles ce type de scenarios estfondé peuvent fournir des contraintes temporelles indépendantes pour tester les modèles numériques de convectionmantellique et les interactions panache–panneau plongeant.
Published: 2016
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11. 3D numerical modeling of mantle flow, crustal dynamics and magma genesis associated with slab roll-back and tearing: The eastern Mediterranean case

Author: Pietro Sternai, Taras Gerya, Laurent Guillou-Frottier, Laurent Jolivet, Armel Menant, Laboratoire des Fluides Complexes et leurs Réservoirs (LFCR), TOTAL FINA ELF-Université de Pau et des Pays de l'Adour (UPPA)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Géodynamique - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Earth Sciences [University of Cambridge], University of Cambridge [UK] (CAM), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), European Project: 290864,EC:FP7:ERC,ERC-2011-ADG_20110209,RHEOLITH(2012), Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-TOTAL FINA ELF, Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Department of Earth Sciences, University of Cambridge, Menant, A, Sternai, P, Jolivet, L, Guillou-Frottier, L, and Gerya, T
Subjects: 3D numerical modeling, 010504 meteorology & atmospheric sciences, Continental collision, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), Geochemistry and Petrology, Lithosphere, Asthenosphere, asthenospheric flow, Earth and Planetary Sciences (miscellaneous), subduction-related magmatism, slab tearing, Geophysic, 0105 earth and related environmental sciences, lithospheric deformation, Subduction, Crust, Geophysics, slab roll-back, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Slab window, Slab, Geology
Abstract: International audience; Interactions between subduction dynamics and magma genesis have been intensely investigated, resulting in several conceptual models derived from geological, geochemical and geophysical data. To provide physico-chemical constraints on these conceptual models, self-consistent numerical simulations containing testable thermo-mechanical parameters are required, especially considering the three-dimensional (3D) natural complexity of subduction systems. Here, we use a 3D high-resolution petrological and thermo-mechanical numerical model to quantify the relative contribution of oceanic and continental subduction/collision, slab roll-back and tearing to magma genesis and transport processes. Our modeling results suggest that the space and time distribution and composition of magmas in the overriding plate is controlled by the 3D slab dynamics and related asthenospheric flow. Moreover, the decrease of the bulk lithospheric strength induced by mantle- and crust-derived magmas promotes the propagation of strike-slip and extensional fault zones through the overriding crust as response to slab roll-back and continental collision. Reduction of the lithosphere/asthenosphere rheological contrast by lithospheric weakening also favors the transmission of velocities from the flowing mantle to the crust. Similarities between our modeling results and the late Cenozoic tectonic and magmatic evolution across the eastern Mediterranean region suggest an efficient control of mantle flow on the magmatic activity in this region, which in turn promotes lithospheric deformation by mantle drag via melt-induced weakening effects.
Published: 2016
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12. Signatures of Life Detected in Images of Rocks Using Neural Network Analysis Demonstrate New Potential for Searching for Biosignatures on the Surface of Mars

Author: Corenblit, Dov, Decaux, Olivier, Delmotte, Sébastien, Toumazet, Jean-Pierre, Arrignon, Florent, André, Marie-Françoise, Darrozes, José, Davies, Neil S, Julien, Frédéric, Otto, Thierry, Ramillien, Guillaume, Roussel, Erwan, Steiger, Johannes, Viles, Heather, Corenblit, Dov [0000-0002-2431-7913], Apollo - University of Cambridge Repository, Laboratoire de Géographie Physique et Environnementale (GEOLAB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Service de radiologie et imagerie médicale [Rennes] = Radiology [Rennes], CHU Pontchaillou [Rennes], MAD-Environnement, Géosciences Environnement Toulouse (GET), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences [University of Cambridge], University of Cambridge [UK] (CAM), Laboratoire Ecologie Fonctionnelle et Environnement (LEFE), Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), University of Oxford, and Observatoire Midi-Pyrénées (OMP), Toulouse, France
Subjects: Geologic Sediments, Extraterrestrial Environment, Fossils, Biogeomorphology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Mars, Astrobiology, Agricultural and Biological Sciences (miscellaneous), Neural network, Space and Planetary Science, [SDE]Environmental Sciences, Exobiology, Biosignatures, Humans, Microbially induced sediment structures, Neural Networks, Computer
Abstract: Microorganisms play a role in the construction or modulation of various types of landforms. They are especially notable for forming microbially induced sedimentary structures (MISS). Such microbial structures have been considered to be among the most likely biosignatures that might be encountered on the martian surface. Twenty-nine algorithms have been tested with images taken during a laboratory experiment for testing their performance in discriminating mat cracks (MISS) from abiotic mud cracks. Among the algorithms, neural network types produced excellent predictions with similar precision of 0.99. Following that step, a convolutional neural network (CNN) approach has been tested to see whether it can conclusively detect MISS in images of rocks and sediment surfaces taken at different natural sites where present and ancient (fossil) microbial mat cracks and abiotic desiccation cracks were observed. The CNN approach showed excellent prediction of biotic and abiotic structures from the images (global precision, sensitivity, and specificity, respectively, 0.99, 0.99, and 0.97). The key areas of interest of the machine matched well with human expertise for distinguishing biotic and abiotic forms (in their geomorphological meaning). The images indicated clear differences between the abiotic and biotic situations expressed at three embedded scales: texture (size, shape, and arrangement of the grains constituting the surface of one form), form (outer shape of one form), and pattern of form arrangement (arrangement of the forms over a few square meters). The most discriminative components for biogenicity were the border of the mat cracks with their tortuous enlarged and blistered morphology more or less curved upward, sometimes with thin laminations. To apply this innovative biogeomorphological approach to the images obtained by rovers on Mars, the main physical and biological sources of variation in abiotic and biotic outcomes must now be further considered.
Published: 2023
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13. Isotope clues on the origin of Mg/Si variations in chondrites and planetary bodies

Author: Bourdon, Bernard, Tipper, E.T., Fitoussi, Caroline, Stracke, Andreas, Institute of Geochemistry and Petrology, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Laboratoire de Sciences de la Terre (LST), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Institute of Geochemistry and Petrology [ETH Zürich], Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Department of Earth Sciences [University of Cambridge], École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Geochemistry, Isotope, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]
Abstract: 73rd Annual Meeting of the Meteoritical-Society ; New York, NY ; July 26-30, 2010; International audience
Published: 2010

14. Volcanic air pollution and human health: recent advances and future directions

Author: Stewart, C, Damby, DE, Horwell, CJ, Elias, T, Ilyinskaya, E, Tomašek, I, Longo, BM, Schmidt, A, Carlsen, HK, Mason, E, Baxter, PJ, Cronin, S, Witham, C, Stewart, C [0000-0002-3781-6308], Damby, DE [0000-0002-3238-3961], Horwell, CJ [0000-0002-0148-6933], Elias, T [0000-0002-9592-4518], Ilyinskaya, E [0000-0002-3663-9506], Tomašek, I [0000-0003-3743-6628], Longo, BM [0000-0003-0502-3749], Schmidt, Anja [0000-0001-8759-2843], Carlsen, HK [0000-0003-1656-9624], Mason, Emily [0000-0002-7050-6475], Baxter, PJ [0000-0001-8700-1249], Cronin, S [0000-0001-7499-603X], Witham, C [0000-0001-5037-6987], Apollo - University of Cambridge Repository, School of Health Sciences, Massey University, U.S. Geological Survey, Volcano Science Center, Durham University, University of Leeds, Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement et la société-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Orvis School of Nursing, University of Nevada, University of Cambridge [UK] (CAM), University of Iceland [Reykjavik], University of Gothenburg (GU), Department of Earth Sciences [University of Cambridge], Department of Public Health and Primary Care, University of Cambridge, School of Geography and Environmental Science University of Auckland, UK METOFFICE EXETER GBR, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), ANR-16-IDEX-0001,CAP 20-25,CAP 20-25(2016), Schmidt, A [0000-0001-8759-2843], and Mason, E [0000-0002-7050-6475]
Subjects: 2 Aetiology, Volcanic emissions, Air pollution, 37 Earth Sciences, 3705 Geology, Review, Looking Backwards and Forwards in Volcanology: A Collection of Perspectives on the Trajectory of a Science, 3703 Geochemistry, Risk management, [SDU]Sciences of the Universe [physics], Geochemistry and Petrology, 2.2 Factors relating to the physical environment, Climate-Related Exposures and Conditions, Generic health relevance, Health effects, Perspectives, Health hazard assessment
Abstract: Volcanic air pollution from both explosive and effusive activity can affect large populations as far as thousands of kilometers away from the source, for days to decades or even centuries. Here, we summarize key advances and prospects in the assessment of health hazards, effects, risk, and management. Recent advances include standardized ash assessment methods to characterize the multiple physicochemical characteristics that might influence toxicity; the rise of community-based air quality monitoring networks using low-cost gas and particulate sensors; the development of forecasting methods for ground-level concentrations and associated public advisories; the development of risk and impact assessment methods to explore health consequences of future eruptions; and the development of evidence-based, locally specific measures for health protection. However, it remains problematic that the health effects of many major and sometimes long-duration eruptions near large populations have gone completely unmonitored. Similarly, effects of prolonged degassing on exposed populations have received very little attention relative to explosive eruptions. Furthermore, very few studies have longitudinally followed populations chronically exposed to volcanic emissions; thus, knowledge gaps remain about whether chronic exposures can trigger development of potentially fatal diseases. Instigating such studies will be facilitated by continued co-development of standardized protocols, supporting local study teams and procuring equipment, funding, and ethical permissions. Relationship building between visiting researchers and host country academic, observatory, and agency partners is vital and can, in turn, support the effective communication of health impacts of volcanic air pollution to populations, health practitioners, and emergency managers.
Published: 2022
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15. Deep carbon cycle constrained by carbonate solubility

Author: Mohamed Mezouar, Stefan Farsang, Remo N. Widmer, Simon A. T. Redfern, Angelika Dorothea Rosa, Xiaolei Feng, Chaoshuai Zhao, Jin Liu, Marion Louvel, Farsang, Stefan [0000-0002-4918-5566], Mezouar, Mohamed [0000-0001-5336-544X], Rosa, Angelika D [0000-0002-2304-1943], Widmer, Remo N [0000-0001-7664-4791], Feng, Xiaolei [0000-0003-4410-4576], Liu, Jin [0000-0002-1670-8199], Redfern, Simon AT [0000-0001-9513-0147], Apollo - University of Cambridge Repository, Redfern, Simon A T [0000-0001-9513-0147], Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Institut für Mineralogie-Münster, Westfälische Wilhelms-Universität Münster (WWU), Center for High Pressure Science & Technology Advanced Research (HPSTAR), European Synchrotron Radiation Facility (ESRF), Swiss Federal Laboratories for Materials Science and Technology (EMPA), Asian School of the Environment (ASE), Nanyang Technological University [Singapour], Rosa, Angelika D. [0000-0002-2304-1943], Widmer, Remo N. [0000-0001-7664-4791], and Redfern, Simon A. T. [0000-0001-9513-0147]
Subjects: Rhodochrosite, 010504 meteorology & atmospheric sciences, Science, General Physics and Astronomy, Mineralogy, chemistry.chemical_element, 010502 geochemistry & geophysics, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Article, Carbon cycle, chemistry.chemical_compound, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Solubility, Dissolution, 0105 earth and related environmental sciences, 13 Climate Action, Multidisciplinary, General Chemistry, 704/2151/330, Geochemistry, chemistry, 13. Climate action, Slab, Carbonate, 704/2151/209, Carbon, Magnesite
Abstract: Earth’s deep carbon cycle affects atmospheric CO2, climate, and habitability. Owing to the extreme solubility of CaCO3, aqueous fluids released from the subducting slab could extract all carbon from the slab. However, recycling efficiency is estimated at only around 40%. Data from carbonate inclusions, petrology, and Mg isotope systematics indicate Ca2+ in carbonates is replaced by Mg2+ and other cations during subduction. Here we determined the solubility of dolomite [CaMg(CO3)2] and rhodochrosite (MnCO3), and put an upper limit on that of magnesite (MgCO3) under subduction zone conditions. Solubility decreases at least two orders of magnitude as carbonates become Mg-rich. This decreased solubility, coupled with heterogeneity of carbon and water subduction, may explain discrepancies in carbon recycling estimates. Over a range of slab settings, we find aqueous dissolution responsible for mobilizing 10 to 92% of slab carbon. Globally, aqueous fluids mobilise \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${35}_{-17}^{+20}$$\end{document}35−17+20% (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${27}_{-13}^{+16}$$\end{document}27−13+16 Mt/yr) of subducted carbon from subducting slabs., Carbonate mineral aqueous solubility decreases as carbonates become more Mg-rich during subduction. Coupled with regional variations in amounts of carbon and water subducted, this explains discrepancies in estimates of carbon recycling, suggesting that only around a third returns to the surface.
Published: 2021
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16. On the stoichiometry of zirconium carbide

Author: Dhan-sham Rana, Niccolo Le Brun, Claudia Gasparrini, Denis Horlait, Ian Farnan, Christos N. Markides, William E. Lee, Centre for Nuclear Engineering (CNE) & Department of Materials, Imperial College London, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Imperial College London, Department of Chemical Engineering, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Nuclear Futures Institute, Bangor University, Bangor, Gasparrini, Claudia [0000-0001-8343-4733], Horlait, Denis [0000-0002-2645-6896], Markides, Christos N. [0000-0002-4219-1867], Farnan, Ian [0000-0001-7844-5112], Apollo - University of Cambridge Repository, Markides, Christos N [0000-0002-4219-1867], and Engineering and Physical Sciences Research Council
Subjects: 639/638/263/915, Thermogravimetric analysis, Materials science, 145, Analytical chemistry, lcsh:Medicine, chemistry.chemical_element, 02 engineering and technology, sub-03, 639/4077/4091/4093, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 639/301/299, 01 natural sciences, Zirconium carbide, chemistry.chemical_compound, Lattice constant, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, 0103 physical sciences, 128, lcsh:Science, [PHYS]Physics [physics], 010302 applied physics, Zirconium, Multidisciplinary, Nuclear fusion and fission, lcsh:R, article, Solid-state chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Characterization (materials science), chemistry, Elemental analysis, 140/131, lcsh:Q, Atomic ratio, 5106 Nuclear and Plasma Physics, 0210 nano-technology, 51 Physical Sciences, Stoichiometry, Materials for energy and catalysis
Abstract: The dependencies of the enhanced thermomechanical properties of zirconium carbide (ZrCx) with sample purity and stoichiometry are still not understood due to discrepancies in the literature. Multiple researchers have recently reported a linear relation between the carbon to zirconium atomic ratio (C/Zr) and the lattice parameter, in contrast with a more established relationship that suggests that the lattice parameter value attains a maximum value at a C/Zr ~ 0.83. In this study, the relationship between C/Zr atomic ratio and the lattice parameter is critically assessed: it is found that recent studies reporting the thermophysical properties of ZrCx have unintentionally produced and characterised samples containing zirconium oxycarbide. To avoid such erroneous characterization of ZrCx thermophysical properties in the future, we propose a method for the accurate measurement of the stoichiometry of ZrCx using three independent experimental techniques, namely: elemental analysis, thermogravimetric analysis and nuclear magnetic resonance spectroscopy. Although a large scatter in the results (ΔC/Zr = 0.07) from these different techniques was found when used independently, when combining the techniques together consistent values of x in ZrCx were obtained.
Published: 2020
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17. Avalanche criticality during ferroelectric/ferroelastic switching

Author: Blai Casals, Guillaume F. Nataf, Ekhard K. H. Salje, Casals, Blai [0000-0002-2941-1861], Nataf, Guillaume F [0000-0001-9215-4717], Apollo - University of Cambridge Repository, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Department of Materials Science and Metallurgy [Cambridge University] (DMSM), and Nataf, Guillaume F. [0000-0001-9215-4717]
Subjects: Ferroelectrics and multiferroics, 639/301/119/996, Field (physics), 123, Science, General Physics and Astronomy, 02 engineering and technology, sub-03, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Condensed Matter::Materials Science, Critical point (thermodynamics), 0103 physical sciences, 128, 010306 general physics, ComputingMilieux_MISCELLANEOUS, 40 Engineering, [PHYS]Physics [physics], Physics, 3403 Macromolecular and Materials Chemistry, 132, Multidisciplinary, Condensed matter physics, 34 Chemical Sciences, article, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, Coercivity, Scale invariance, 021001 nanoscience & nanotechnology, Ferroelectricity, Hysteresis, Phase transitions and critical phenomena, Domain wall (magnetism), Mean field theory, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 639/766/530/2795, 0210 nano-technology, 51 Physical Sciences
Abstract: Field induced domain wall displacements define ferroelectric/ferroelastic hysteresis loops, which are at the core of piezoelectric, magnetoelectric and memristive devices. These collective displacements are scale invariant jumps with avalanche characteristics. Here, we analyse the spatial distribution of avalanches in ferroelectrics with different domain and transformation patterns: Pb(Mg1/3Nb2/3)O3–PbTiO3 contains complex domains with needles and junction patterns, while BaTiO3 has parallel straight domains. Nevertheless, their avalanche characteristics are indistinguishable. The energies, areas and perimeters of the switched regions are power law distributed with exponents close to predicted mean field values. At the coercive field, the area exponent decreases, while the fractal dimension increases. This fine structure of the switching process has not been detected before and suggests that switching occurs via criticality at the coercive field with fundamentally different switching geometries at and near this critical point. We conjecture that the domain switching process in ferroelectrics is universal at the coercive field., While classical approaches rely on the study of individual ferroelectric domain wall movement on long time scales, the authors consider collective movements of domain walls during short time scales, characterized by discrete jumps, as indicators of avalanches on a broad range of scales.
Published: 2020
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18. Synchronous timing of abrupt climate changes during the last glacial period

Author: Dominik Fleitmann, John Hellstrom, Eric W. Wolff, Sune Olander Rasmussen, Xu Zhang, Russell N. Drysdale, Emilie Capron, Ellen Corrick, Isabelle Couchoud, University of Melbourne, Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Key Laboratory of Western China's Environmental Systems (Ministry of Education), Lanzhou University, Alfred Wegener Institute [Potsdam], Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), CAS Center for Excellence in Tibetan Plateau Earth Sciences, University of Basel, Department of Environmental Sciences, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Corrick, Ellen C [0000-0001-5020-160X], Drysdale, Russell N [0000-0001-7867-031X], Hellstrom, John C [0000-0001-9427-3525], Capron, Emilie [0000-0003-0784-1884], Rasmussen, Sune Olander [0000-0002-4177-3611], Zhang, Xu [0000-0003-1833-9689], Fleitmann, Dominik [0000-0001-5977-8835], Couchoud, Isabelle [0000-0002-7166-9575], Wolff, Eric [0000-0002-5914-8531], and Apollo - University of Cambridge Repository
Subjects: 010504 meteorology & atmospheric sciences, Atmospheric circulation, sub-01, [SDE.MCG]Environmental Sciences/Global Changes, Speleothem, Climate change, 3705 Geology, 010502 geochemistry & geophysics, Monsoon, 01 natural sciences, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, East Asian Monsoon, Glacial period, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, 13 Climate Action, geography, Multidisciplinary, geography.geographical_feature_category, 37 Earth Sciences, 3709 Physical Geography and Environmental Geoscience, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Climatology, South american, Abrupt climate change, Geology
Abstract: Many geographically dispersed records from across the globe reveal the occurrence of abrupt climate changes, called interstadial events, during the last glacial period. These events appear to have happened at the same time, but the difficulty of determining absolute dates in many of the records have made that proposition difficult to prove. Corrick et al. present results from 63 precisely dated speleothems that confirm the synchrony of those interstadial events. Their results also provide a tool with which to validate model simulations of abrupt climate change and calibrate other time series such as ice-core chronologies.Science, this issue p. 963Abrupt climate changes during the last glacial period have been detected in a global array of palaeoclimate records, but our understanding of their absolute timing and regional synchrony is incomplete. Our compilation of 63 published, independently dated speleothem records shows that abrupt warmings in Greenland were associated with synchronous climate changes across the Asian Monsoon, South American Monsoon, and European-Mediterranean regions that occurred within decades. Together with the demonstration of bipolar synchrony in atmospheric response, this provides independent evidence of synchronous high-latitude–to-tropical coupling of climate changes during these abrupt warmings. Our results provide a globally coherent framework with which to validate model simulations of abrupt climate change and to constrain ice-core chronologies.
Published: 2020

19. Discontinuous temperature-dependent macroscopic strain due to ferroelastic domain switching and structural phase transitions in barium strontium titanate

Author: Redfern, Simon [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ (United Kingdom)]
Published: 2007
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20. Memory effect of a mechanical anomaly related to ferroelastic domain switching in rhombohedral lead zirconate titanate ceramics

Author: Harrison, Richard [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ United Kingdom (United Kingdom)]
Published: 2006
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21. Elastic softening of zircon by radiation damage

Author: Salje, Ekhard [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ (United Kingdom)]
Published: 2006
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22. Solid solubilities of (La Nd,){sub 2}(Zr,Ti){sub 2}O{sub 7} phases deduced by neutron diffraction

Author: Redfern, Simon [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ (United Kingdom)]
Published: 2005
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23. Energetics of intrinsic point defects in ZrSiO{sub 4}

Author: Artacho, Emilio [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ (United Kingdom)]
Published: 2005
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24. Radiation damage effects in the perovskite CaTiO{sub 3} and resistance of materials to amorphization

Author: Dove, Martin [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ (United Kingdom)]
Published: 2004
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25. Intrinsic point defects and volume swelling in ZrSiO{sub 4} under irradiation

Author: Artacho, Emilio [Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ (United Kingdom)]
Published: 2004
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26. Nanoscale Imaging of High‐Field Magnetic Hysteresis in Meteoritic Metal Using X‐Ray Holography

Author: Roberts Blukis, Richard J. Harrison, Bastian Pfau, Christian M. Günther, Piet Hessing, Stefan Eisebitt, Joshua F. Einsle, Pfau, B., 2 Max‐Born‐Institut Berlin Germany, Günther, C. M., 3 Center for Electron Microscopy (ZELMI) Technische Universität Berlin Berlin Germany, Hessing, P., Eisebitt, S., Einsle, J., 5 School of Geographical and Earth Sciences University of Glasgow Glasgow UK, Harrison, R. J., and 6 Department of Earth Sciences University of Cambridge Cambridge UK
Subjects: 010504 meteorology & atmospheric sciences, Holography, 538.7, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, law.invention, X‐ray holography, Paramagnetism, Geochemistry and Petrology, law, ddc:550, Tetrataenite, Nanoscopic scale, 0105 earth and related environmental sciences, cloudy zone, Condensed matter physics, X-ray, Magnetic hysteresis, Geophysics, Ferromagnetism, 13. Climate action, Tazewell meteorite, Antitaenite, engineering, Geology
Abstract: Stable paleomagnetic information in meteoritic metal is carried by the “cloudy zone”: ~1–10 μm‐wide regions containing islands of ferromagnetic tetrataenite embedded in a paramagnetic antitaenite matrix. Due to their small size and high coercivity (theoretically up to ~2.2 T), the tetrataenite islands carry very stable magnetic remanence. However, these characteristics also make it difficult to image their magnetic state with the necessary spatial resolution and applied magnetic field. Here, we describe the first application of X‐ray holography to image the magnetic structure of the cloudy zone of the Tazewell IIICD meteorite with spatial resolution down to ~40 nm and in applied magnetic fields up to ±1.1 T, sufficient to extract high‐field hysteresis data from individual islands. Images were acquired as a function of magnetic field applied both parallel and perpendicular to the surface of a ~100 nm‐thick slice of the cloudy zone. Broad distributions of coercivity are observed, including values that likely exceed the maximum applied field. Horizontal offsets in the hysteresis loops indicate an interaction field distribution with half width of ~100 mT between the islands in their room temperature single‐domain state, providing a good match to first‐order reversal curve diagrams. The results suggest that future models of remanence acquisition in the cloudy zone should take account of strong interactions in order to extract quantitative estimates of the paleofield., Plain Language Summary: Magnetic fields played a significant role in the formation of the solar system and the evolution of the early planetary bodies in the first few million years after solar system formation. Knowledge about magnetic fields in the early solar system can be obtained from meteorites. Some meteorite types contain abundant iron‐nickel alloy that contains nanoscale “cloudy zone” regions (named after their appearance in an optical microscope) that can preserve magnetic information over 4.5 billion years. The cloudy zone is a complex material consisting of magnetically stable nanoscale particles embedded in a nonmagnetic matrix in very close proximity to one another. The fine scale and extreme magnetic stability of the cloudy zone make it challenging to study using conventional magnetic microscopy techniques. Here, we apply X‐ray holography for the first time to image the magnetization of individual magnetic particles and how they respond to magnetic fields. This new approach enables us to measure the magnetic properties of individual nanoscale particles, providing the first direct measurement of their magnetic stability and the strength of particle interactions. These measurements will improve our understanding of the magnetic information carried by the cloudy zone, and of how to extract information about solar system magnetic fields., Key Points: X‐ray holography enables magnetization of natural samples to be imaged with ~40 nm resolution and in applied magnetic fields up to ±1.1 T. Meteoritic cloudy zone consists of strongly interacting single‐domain particles with single‐particle coercivities up to 1 T. Average interaction fields between particles in the cloudy zone are of the order 100–200 mT., European Commission (EC) http://dx.doi.org/10.13039/501100000780, Europen Commission, European Research Council (ERC) http://dx.doi.org/10.13039/501100000781, European Research Council under the European Union's Seventh Framework Programme
Published: 2020

27. A global comparison of the timing of millennial-scale climate events from published speleothem records

Author: Corrick, Ellen, Drysdale, Russell N., Hellstrom, John C., Capron, Emilie, Wolff, Eric, Fleitmann, Dominik, Couchoud, Isabelle, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), School of Geography, University of Melbourne, School of Earth Sciences [Melbourne], Faculty of Science [Melbourne], University of Melbourne-University of Melbourne, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Université de Bern, Inst. Geol. Sciences, and Université de Bern
Subjects: Millenial climatic variability, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, [SDE.MCG]Environmental Sciences/Global Changes, [SDE]Environmental Sciences, Palaeoclimate, Speleothem, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Abrupt climate change, ComputingMilieux_MISCELLANEOUS, Last glacial period
Abstract: International audience
Published: 2018

28. A high spatial resolution synchrotron Mössbauer study of the Tazewell IIICD and Esquel pallasite meteorites

Author: Roberts Blukis, Aleksandr I. Chumakov, Richard J. Harrison, Rudolf Rüffer, Harrison, Richard [0000-0003-3469-762X], Apollo - University of Cambridge Repository, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), and European Synchrotron Radiation Facility (ESRF)
Subjects: tetrataenite, 010504 meteorology & atmospheric sciences, plessite, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Mineralogy, Plessite, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Electron spectroscopy, law.invention, Tazewell IIIC, law, kamacite, Tetrataenite, 0105 earth and related environmental sciences, antitaenite, Esquel pall, synchrotron Mössbauer source, cloudy zone, Chemistry, Pallasite, Articles, Synchrotron, Kamacite, Geophysics, Meteorite, Space and Planetary Science, Antitaenite, engineering, Original Article
Abstract: International audience; Metallic phases in the Tazewell IIICD iron and Esquel pallasite meteorites were examined using Fe-57 synchrotron Mossbauer spectroscopy. Spatial resolution of 10-20m was achieved, together with high throughput, enabling individual spectra to be recorded in less than 1h. Spectra were recorded every 5-10m, allowing phase fractions and hyperfine parameters to be traced along transects of key microstructural features. The main focus of the study was the transitional region between kamacite and plessite, known as the cloudy zone. Results confirm the presence of tetrataenite and antitaenite in the cloudy zone as its only components. However, both phases were also found in plessite, indicating that antitaenite is not restricted exclusively to the cloudy zone, as previously thought. The confirmation of paramagnetic antitaenite as the matrix phase of the cloudy zone contrasts with recent observations of a ferromagnetic matrix phase using X-ray photoemission electron spectroscopy. Possible explanations for the different results seen using these techniques are proposed
Published: 2017
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29. The large-scale evolution of neodymium isotopic composition in the global modern and Holocene ocean revealed from seawater data and other records

Author: Kazuyo, Tachikawa, Arsouze, Thomas, Bayon, Germain, Bory, Aloys, Colin, Christophe, Dutay, Jean-Claude, Frank, Norbert, Giraud, Xavier, Gourlan, Alexandra T., Jeandel, Catherine, Lacan, François, Meynadier, Laure, Montagna, Paolo, Piotrowski, Alexander M., Plancherel, Yves, Pucéat, Emmanuelle, Roy-Barman, Matthieu, Waelbroeck, Claire, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), École Nationale Supérieure de Techniques Avancées (ENSTA Paris), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord]), Géosciences Paris Saclay (GEOPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institute of Environmental Physics [Heidelberg] (IUP), Universität Heidelberg [Heidelberg] = Heidelberg University, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPG Paris), Istituto di Scienze Marine [Bologna] (ISMAR), Istituto di Science Marine (ISMAR ), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)-National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Department of Earth Sciences [University of Cambridge], University of Cambridge [UK] (CAM), Department of Earth Sciences [Oxford], University of Oxford, Biogéosciences [UMR 6282] (BGS), Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), and Tachikawa, Kazuyo
Subjects: [SDU.STU] Sciences of the Universe [physics]/Earth Sciences, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences
Abstract: International audience; The large-scale evolution of neodymium isotopic composition in the global modern and Holocene ocean revealed from seawater data and other records. Kazuyo Tachikawa and project members Neodymium isotopic compositions (143 Nd/ 144 Nd or ε Nd) have been used as a tracer of water masses and lithogenic inputs to the ocean. To further evaluate the faithfulness of this tracer, we have updated a global seawater ε Nd database and combined it with hydrography parameters (temperature, salinity, nutrients and oxygen concentrations), carbon isotopic ratio and radiocarbon of dissolved inorganic carbon. Archive ε Nd data are compiled for leachates, foraminiferal tests, deep-sea corals and fish teeth/debris from the Holocene period. At water depths ≥ 1500m, property-property plots show clear correlations between seawater ε Nd and the other variables, suggesting that large-scale water mass mixing is a primary control of deepwater ε Nd distribution. At ≥ 200m, basin-scale seawater T-S-ε Nd diagrams demonstrate the isotopic evolution of different water masses. Seawater and archive ε Nd values are compared using property-property plots and T-S-ε Nd diagrams. Archive values generally agree with corresponding seawater values although they tend to be at the upper limit in the Pacific. Both positive and negative offsets exist in the northern North Atlantic. Applying multiple regression analysis to deep (≥ 1500m) seawater data, we established empirical equations that predict the main, large-scale, deepwater ε Nd trends from hydrography parameters. Large offsets from the predicted values are interpreted as a sign of significant local/regional influence. Dominant continental influence on seawater and archive ε Nd is observed mainly within 1,000 km from the continents. Generally, seawater and archive ε Nd values form gradual latitudinal trend in the Atlantic and Pacific at depths ≥ 600m, consistent with the idea that Nd isotopes help distinguish between northern/southern sourced water contributions at intermediate and deep water depths.
Published: 2017

30. Deglaciation and glacial erosion: A joint control on magma productivity by continental unloading

Author: Sébastien Castelltort, Pietro Sternai, Luca Caricchi, Jean-Daniel Champagnac, Division of Geological and Planetary Sciences [Pasadena], California Institute of Technology (CALTECH), Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Department of Earth Sciences, University of Geneva, University of Geneva [Switzerland], Geological Institute [ETH Zürich], Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), Sternai, P, Caricchi, L, Castelltort, S, and Champagnac, J
Subjects: 010504 meteorology & atmospheric sciences, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], Earth science, Forcing (mathematics), deglaciation, 010502 geochemistry & geophysics, glacial erosion, 01 natural sciences, Lithosphere, ddc:550, Deglaciation, Glacial period, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, Geophysic, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, magma production, Magmatism, continental unloading, 15. Life on land, Geophysics, Volcano, Erosion, 13. Climate action, Magma, Interglacial, General Earth and Planetary Sciences, Earth and Planetary Sciences (all), Geology
Abstract: International audience; Glacial-interglacial cycles affect the processes through which water and rocks are redistributed across the Earth's surface, thereby linking the solid Earth and climate dynamics. Regional and global scale studies suggest that continental lithospheric unloading due to ice melting during the transition to interglacials leads to increased continental magmatic, volcanic, and degassing activity. Such a climatic forcing on the melting of the Earth's interior, however, has always been evaluated regardless of continental unloading by glacial erosion, albeit the density of rock exceeds that of ice by approximately 3 times. Here we present and discuss numerical results involving synthetic but realistic topographies, ice caps, and glacial erosion rates suggesting that erosion may be as important as deglaciation in affecting continental unloading. Our study represents an additional step toward a more general understanding of the links between a changing climate, glacial processes, and the melting of the solid Earth.
Published: 2016
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31. Interpreting the Ca isotope record of marine biogenic carbonates

Author: Aradhna Tripati, N. G. Sime, Christina L. De La Rocha, Albert Galy, Edward T. Tipper, Mike J. Bickle, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Department of Earth Sciences [Cambridge, UK]
Subjects: Calcite, 010504 meteorology & atmospheric sciences, Isotope, Aragonite, Geochemistry, Sediment, Weathering, Fractionation, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, chemistry.chemical_compound, Paleontology, Isotope fractionation, chemistry, 13. Climate action, Geochemistry and Petrology, engineering, Carbonate, 14. Life underwater, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, Geology, 0105 earth and related environmental sciences
Abstract: International audience; An 18 million year record of the Ca isotopic composition (d44/42Ca) of planktonic foraminiferans from ODP site 925, in the Atlantic, on the Ceara Rise, provides the opportunity for critical analysis of Ca isotope-based reconstructions of the Ca cycle. d44/42Ca in this record averages +0.37 ± 0.05 (1r SD) and ranges from +0.21‰ to +0.52‰. The record is a good match to previously published Neogene Ca isotope records based on foraminiferans, but is not similar to the record based on bulk carbonates, which has values that are as much as 0.25‰ lower. Bulk carbonate and planktonic foraminiferans from core tops differ slightly in their d44/42Ca (i.e., by 0.06 ± 0.06‰ (n = 5)), while the difference between bulk carbonate and foraminiferan values further back in time is markedly larger, leaving open the question of the cause of the difference. Modeling the global Ca cycle from downcore variations in d44/42Ca by assuming fixed values for the isotopic composition of weathering inputs (d44/42Caw) and for isotope fractionation associated with the production of carbonate sediments (Dsed) results in unrealistically large variations in the total mass of Ca2+ in the oceans over the Neogene. Alternatively, variations of ±0.05‰ in the Ca isotope composition of weathering inputs or in the extent of fractionation of Ca isotopes during calcareous sediment formation could entirely account for variations in the Ca isotopic composition of marine carbonates. Ca isotope fractionation during continental weathering, such as has been recently observed, could easily result in variations in d44/42Caw of a few tenths of permil. Likewise a difference in the fractionation factors associated with aragonite versus calcite formation could drive shifts in Dsed of tenths of permil with shifts in the relative output of calcite and aragonite from the ocean. Until better constraints on variations in d44/42Caw and Dsed have been established, modeling the Ca2+ content of seawater from Ca isotope curves should be approached cautiously.
Published: 2007
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32. Negligible temperature dependence of calcium isotope fractionation in 12 species of planktonic foraminifera

Author: Christina L. De La Rocha, Albert Galy, N. G. Sime, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Department of Earth Sciences [Cambridge, UK]
Subjects: 010504 meteorology & atmospheric sciences, Fractionation, 010502 geochemistry & geophysics, 01 natural sciences, Foraminifera, chemistry.chemical_compound, Isotope fractionation, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), 14. Life underwater, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Calcite, biology, Globigerina bulloides, Plankton, biology.organism_classification, Geophysics, Oceanography, chemistry, 13. Climate action, Space and Planetary Science, Environmental chemistry, Seawater, Enrichment factor, Geology
Abstract: International audience; The influence of temperature on calcium (Ca) isotope fractionation during biomineralization was investigated through the paired analyses of d44/42Ca (via MC-ICP-MS) and d18O on the calcite tests of 12 species of planktonic foraminifera from coretop sediments. Samples were collected from a suite of box-cores from sites between 608N and 308S in the North Atlantic and West Indian oceans, spanning a range in sea surface temperature of 9-27 8C. The d44/42CaSRM915a of the samples ranged from +0.21x to +0.81x over a range in the d18OVPDB of the foraminiferal calcite of between 2.3x and +2.1x. The bulk of the species investigated produced calcite with an average calcite-seawater Ca enrichment factor (e) of 0.65F0.08x (n=45). The globorotaliid species and a single Globigerina bulloides sample were confined to the upper 0.4x of the observed range in d44/42Ca values, with the globorotaliids displaying a lesser degree of fractionation of 0.56F0.23x (n=15), possibly as a result of physiological or metabolic processes such as the production of calcite crusts at depth, leading to the depletion of internal stores of Ca. No significant correlation between temperature and Ca enrichment factor was observed in any of the 12 species of foraminifera investigated. The influence of temperature on e was close to zero for the combined non-globorotaliid species, 0.07F0.10 K (e versus 1000/K; 0.0008F0.0012x 8C 1). The results suggest that the theoretically expected relationship between the Ca enrichment factor and temperature can be obscured by, as yet, unquantified metabolic and physiological processes in nature. These processes are particularly relevant to the globorotaliid species and G. bulloides in this core-top study. Consequently, their effects must be better understood before laboratory-determined temperature calibrations can be applied to downcore material with confidence. Provided that the effects of metabolic and physiological processes on e remain constant through time, Orbulina universa, Globigerinoides sacculifer, Neogloboquadrina pachyderma and Globigerinella aequilateralis are suitable for the investigation of temporal changes in the calcium isotopic composition of seawater.
Published: 2005
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33. Recovery of Thalassiosira weissflogii from nitrogen and silicon starvation

Author: Uta Passow, Christina L. De La Rocha, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Marine Science Institute, University of California [Santa Barbara] (UCSB), and University of California-University of California
Subjects: 0106 biological sciences, Aquatic Science, Oceanography, complex mixtures, 01 natural sciences, 03 medical and health sciences, Nutrient, Algae, Phytoplankton, Photic zone, 14. Life underwater, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 030304 developmental biology, 0303 health sciences, biology, Ecology, 010604 marine biology & hydrobiology, fungi, technology, industry, and agriculture, Plankton, equipment and supplies, biology.organism_classification, Diatom, Thalassiosira weissflogii, 13. Climate action, Upwelling
Abstract: The ecological success of marine diatoms comes despite their unusual additional requirement for silicon, a nutrient that often limits their growth in the ocean. There may be, however, some physiological and ecological advantages to silicon limitation. A model of nitrogen and silicon metabolism in diatoms (Flynn et al. 1997; Flynn and Martin- Jezequel 2000) suggests that silicon-starved diatoms will recover more quickly than nitrogen-starved (but otherwise identical) diatoms on the resupply of nutrients. In culture, following 24 h of stationary phase induced by nutrient exhaustion, silicon-starved Thalassiosira weissflogii displayed maximum growth rates within a few hours of the readdition of silicon. But 37 h elapsed before nitrate-starved cultures began dividing again and nitrate-starved cultures did not reattain maximum growth rates over the period investigated. The model suggests that, in terms of number, cells descended from the nitrate starved will never catch up to cells descended from the silicon starved if both populations are simultaneously supplied with a pulse of nutrients. The longer the lag between nutrient supply and the resumption of growth in the nitrate-starved cells, the greater the proportion of the supplied nutrients that ends up in the descendants of the silicon starved. In the model run, the silicon-starved cells acquired 75% of the added nutrients and the nitrate starved acquired only 25%. Silicon limitation may thus be a mechanism by which diatoms ensure they respond more quickly than other phytoplankton to the upwelling of nutrients into the euphotic zone. Diatoms are astoundingly successful phytoplankton de- spite somewhat uniquely requiring silicon for growth in an ocean largely depleted of silicic acid. Silicon limitation of diatom growth in the ocean has been observed in locations ranging from high-nutrient, upwelling zones in the eastern equatorial Pacific (Dugdale et al. 1995) to the Mississippi River plume (Nelson and Dortch 1996) and the oligotrophic Sargasso Sea (Brzezinski and Nelson 1996). Despite this widespread potential for silicon limitation, diatoms manage to account for 75% of the primary production occurring in high-nutrient and coastal regions of the ocean and as much as 40% of the total annual marine primary production. Be- cause marine primary production constitutes about half of the total of global primary production, marine diatoms carry out 20% of the primary production that occurs on Earth each year.
Published: 2004
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34. Drilling and sampling a natural CO2 reservoir: Implications for fluid flow and CO2-fluid–rock reactions during CO2 migration through the overburden

Author: A. Maskell, Nelly Assayag, Morgan F. Schaller, Julie Gattacceca, Gemma Purser, James Evans, Chris J. Ballentine, Zheng Zhou, Mike J. Bickle, Andreas Busch, F. Chen, Pieter Bertier, Alexandra V. Turchyn, Niko Kampman, Christopher A. Rochelle, Hazel J. Chapman, Department of Earth Sciences [Cambridge, UK], University of Cambridge [UK] ( CAM ), Earth Sciences Department, University of Cambridge, Institute of High Energy Physics ( IHEP ), Chinese Academy of Sciences [Changchun Branch] ( CAS ), Institut de Physique Nucléaire de Lyon ( IPNL ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut de Physique du Globe de Paris ( IPGP ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -IPG PARIS-Université Paris Diderot - Paris 7 ( UPD7 ) -Université de la Réunion ( UR ) -Centre National de la Recherche Scientifique ( CNRS ), University of Cambridge [UK] (CAM), Department of Earth Sciences, University of Cambridge, Institute of High Energy Physics (IHEP), Chinese Academy of Sciences [Changchun Branch] (CAS), Institut de Physique du Globe de Paris (IPGP), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Geochemistry, Aquifer, Fault (geology), 010502 geochemistry & geophysics, 01 natural sciences, Geochemistry and Petrology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Caprock, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Scientific drilling, Geology, [ SDU.STU.GC ] Sciences of the Universe [physics]/Earth Sciences/Geochemistry, 6. Clean water, Overburden, Isotope geochemistry, Fracture (geology), [ SDU.STU.HY ] Sciences of the Universe [physics]/Earth Sciences/Hydrology, Groundwater
Abstract: This paper presents the initial results of a scientific drilling project to recover core and pressurized fluid samples from a natural CO2 reservoir, near the town of Green River, Utah. The drilling targeted a stacked sequence of CO2-charged Jurassic sandstone reservoirs and caprocks, situated adjacent to a CO2-degassing normal fault. This site has actively leaked CO2 from deep supercritical CO2 reservoirs at depth > 2 km within the basin for over 400,000 years. The project objectives were to gather samples to examine reactive fluid flow in the reservoirs, caprocks and faults, during migration of CO2 through the geological overburden from the deep supercritical CO2 reservoirs. Downhole fluid sampling and fluid element and isotope geochemistry show that the shallow reservoirs are being actively fed by inflow of CO2-saturated brines through the faults. Comparisons of shallow and deep fluid geochemistry suggest that: (i) CO2 and CO2-charged brines co-migrated from the deep reservoirs, (ii) the CO2-saturated brines migrating from depth interact with significant volumes of meteoric groundwater in aquifers in the shallower Permian and Jurassic sandstones, diluting the brine composition, and (iii) that a significant fraction of the CO2 migrating from depth is dissolved in these brine–meteoric water mixtures, with > 99% of the CO2 in fluids sampled from the shallow reservoirs being derived during fluid migration, after the fluids left their source reservoir. The 87Sr/86Sr ratio of the brine flowing through the faults is significantly elevated due to the addition of Sr from silicate mineral dissolution during fluid migration. The association of bleached sandstones in the core with CO2-rich fluids supports interpretations from elsewhere that CO2-charged brines with CH4 or H2S reductants can dissolve hematite present within the sediment. Analysis of fluid geochemistry and sandstone petrology suggests that the CO2-rich fluids dissolve carbonate, hematite and gypsum in the reservoirs, as they flow away from the faults. Element and isotope geochemistry of fluid samples from the drillhole and Crystal Geyser constrain mixing models which show that, within the Navajo Sandstone, the reservoir fluids are undergoing complex mixing of: (i) CO2-saturated brine inflowing from the fault, (ii) CO2-undersaturated meteoric groundwater flowing through the reservoir and (iii) reacted CO2-charged brines flow through fracture zones in the overlying Carmel Formation caprock, into the formations above. Such multi-scale mixing processes may significantly improve the efficiency with which groundwaters dissolve the migrating CO2.
Published: 2014
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35. Sensitivity of silicon isotopes to whole-ocean changes in the silica cycle

Author: Mike J. Bickle, Christina L. De La Rocha, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences, University of Cambridge, and University of Cambridge [UK] (CAM)
Subjects: 010504 meteorology & atmospheric sciences, Silicon, biology, chemistry.chemical_element, Geology, 010502 geochemistry & geophysics, Oceanography, biology.organism_classification, 01 natural sciences, Deep sea, chemistry.chemical_compound, Diatom, chemistry, 13. Climate action, Geochemistry and Petrology, Seawater, 14. Life underwater, Glacial period, Silicic acid, Isotopes of silicon, Quaternary, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences
Abstract: International audience; A 2-box model has been used to assess the impact of both long- and short-term budgetary imbalance in the silica cycle on the average silicon isotopic composition (y30Si) of the ocean and marine sediments. Over a 100-ky time span, such as a Quaternary glacial cycle, a sustained change in the riverine flux of silicon to the oceans could alter the average y30Si of seawater and the average y30Si of opal outputs by a few hundredths to a few tenths of permil. This would be largely tied to a change in the y30Si of silicon entering the ocean due to a shift in the proportion of riverine and non-riverine sources of silicon. A doubling of the riverine flux of silicon would have little impact on average marine y30Si, but a sustained halving of river inputs could interfere with use of y30Si as a tracer of nutrient utilization. Studies on the longer term focussed on the transition from a high silicic acid to low silicic acid ocean associated with the rise of the diatoms. This transition is marked by drop in the average y30Si of seawater from greater than +1.9x down to about +0.8x. The isotopic composition of diatom opal, however, has an isotopic composition that sticks close to the +0.8x of the inputs and is thus unlikely to provide information about the transition to the low silicic acid ocean of the modern day. However, the y30Si of opal produced in the deep sea (for example, by sponges) should document this transition.
Published: 2005
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36. Silicon isotope fractionation by marine sponges and the reconstruction of the silicon isotope composition of ancient deep water

Author: Christina L. De La Rocha, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences, University of Cambridge, and University of Cambridge [UK] (CAM)
Subjects: biology, Hexactinellid, Geochemistry, Geology, Fractionation, biology.organism_classification, Paleontology, chemistry.chemical_compound, Sponge spicule, chemistry, Seawater, 14. Life underwater, Silicic acid, Isotopes of silicon, Earth (classical element), [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, Biomineralization
Abstract: International audience; The silicon isotope composition (d30Si) of biogenic opal provides a view of the silica cycle at times in the past. Reconstructions require the knowledge of silicon isotope fractionation during opal biomineralization. The d30Si of specimens of hexactinellid sponges and demosponges growing in the modern ocean ranged from -1.2‰ to -3.7‰ (n=6), corresponding to the production of opal that has a d30Si value 3.8‰ +/- 0.8‰ more negative than seawater silicic acid and a fractionation factor (a) of 0.9964. This is three times the fractionation observed during opal formation by marine diatoms and terrestrial plants and is the largest fractionation of silicon isotopes observed for any natural process on Earth. The d30Si values of sponge spicules across the Eocene- Oligocene boundary at Ocean Drilling Program Site 689 on Maud Rise range from -1.1‰ to -3.0‰, overlapping the range observed for sponges growing in modern seawater.
Published: 2003

37. Ferroelastic aspects of relaxor ferroelectric behaviour in Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3perovskite

Author: Yun Liu, Michael A. Carpenter, Qian Li, S. L. Driver, Raymond Withers, Guillaume F. Nataf, Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), and Research School of Chemistry [Canberra]
Subjects: [PHYS]Physics [physics], 010302 applied physics, Resonant ultrasound spectroscopy, Materials science, Condensed matter physics, General Physics and Astronomy, Mineralogy, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, Dielectric, Atmospheric temperature range, 021001 nanoscience & nanotechnology, 01 natural sciences, Ferroelectricity, Tetragonal crystal system, Transition point, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, Burns temperature, Perovskite (structure)
Abstract: Elastic and anelastic properties of poled and depoled single crystals of Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 with compositions close to the morphotropic boundary have been investigated over the temperature range 5–700 K by resonant ultrasound spectroscopy (RUS) at frequencies of 0.1–1.2 MHz. Steep elastic softening occurs in a temperature interval of at least 250 K as the Vogel-Fulcher freezing interval and cubic → tetragonal transition point, Tc, are approached from above. This is understood in terms of coupling between acoustic modes and central peak mode(s) associated with dynamic polar nano regions (PNR's) below the Burns temperature. Acoustic losses occur in a temperature interval of ∼50 K above Tc, associated with slowing down of the PNR dynamics. The cubic ↔ tetragonal and tetragonal ↔ rhombohedral transitions are accompanied by steep minima in elastic properties, closely analogous to the pattern of softening and stiffening observed in sequences of improper ferroelastic transitions in other perovskites. Variations in the magnitudes of acoustic losses at T
Published: 2013
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38. The silicon isotopic composition of the Ganges and its tributaries

Author: Christina L. De La Rocha, Guillaume Fontorbe, Hazel J. Chapman, Mike J. Bickle, Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences, University of Cambridge, and University of Cambridge [UK] (CAM)
Subjects: 010504 meteorology & atmospheric sciences, Silicon, river chemistry, chemistry.chemical_element, Weathering, Fractionation, sub-02, Biogenic silica, 010502 geochemistry & geophysics, 01 natural sciences, chemical weathering, Adsorption, Geochemistry and Petrology, Tributary, Earth and Planetary Sciences (miscellaneous), Isotopes of silicon, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Hydrology, geography, geography.geographical_feature_category, Ganges, Himalayas, 6. Clean water, Alluvial plain, Geophysics, chemistry, silicon isotopes, 13. Climate action, Space and Planetary Science, Environmental chemistry, Geology
Abstract: The silicon isotopic composition ( δ Si 30 ) of the headwaters of the Ganges River, in the Himalaya, ranged from + 0.49 ± 0.01 ‰ to + 2.17 ± 0.04 ‰ at dissolved silicon (DSi) concentrations of 38 to 239 μM. Both the concentration and isotopic composition of DSi in the tributaries increased between the highest elevations to where the Ganges leaves the Himalayas at Rishikesh. The tributaries exhibit a linear correlation between δ Si 30 and DSi that may represent mixing between a low DSi, low δ Si 30 (e.g., 40 μM, + 0.5 ‰ ) component potentially reflecting fractionation during adsorption of a small fraction of silicon onto iron oxides and a high DSi, high δ Si 30 component (e.g., 240 μM, + 1.7 ‰ ) produced during higher intensity weathering with a greater proportional sequestration of weathered silicon into secondary minerals or biogenic silica. On the Ganges alluvial plain, in the Ganges and the Yamuna, Gomati, and their tributaries, DSi ranged from 122 to 218 μM while δ Si 30 ranged from + 1.03 ± 0.03 ‰ to + 2.46 ± 0.06 ‰ . Highest values of δ Si 30 occurred in the Gomati and its tributaries. In general, the lower DSi and higher δ Si 30 of DSi in these rivers suggests control of both by removal of DSi by secondary mineral formation and/or biogenic silica production. A simple 1-dimensional model with flow through a porous medium is introduced and provides a useful framework for understanding these results.
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39. Elastic excitations in BaTiO_{3} single crystals and ceramics: Mobile domain boundaries and polar nanoregions observed by resonant ultrasonic spectroscopy

Author: Salje, Ekhard, Carpenter, Michael, Nataf, Guillaume F., Picht, Gunnar, Webber, Kyle, Weerasinghe, Jeevaka, Lisenkov, S., Bellaiche, L., Department of Earth Sciences, University of Cambridge, University of Cambridge [UK] (CAM), Institute for Ceramics in Mechanical Engineering, Karlsruhe Institute of Technology, Department of Physics and Institute for Nanoscience and Engineering, University of Arkansas, and Department of Physics, University of South Florida
Subjects: [PHYS]Physics [physics], Condensed Matter::Materials Science, Condensed Matter::Superconductivity, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [CHIM.MATE]Chemical Sciences/Material chemistry, sub-03, ComputingMilieux_MISCELLANEOUS
Abstract: The dynamic properties of elastic domain walls in BaTiO3 were investigated using resonance ultrasonic spectroscopy (RUS). The sequence of phase transitions is characterized by minima in the temperature dependence of RUS resonance frequencies and changes in Q factors (resonance damping). Damping is related to the friction of mobile twin boundaries (90° ferroelectric walls) and distorted polar nanoregions (PNRs) in the cubic phase. Damping is largest in the tetragonal phase of ceramic materials but very low in single crystals. Damping is also small in the low-temperature phases of the ceramic sample and slightly increases with decreasing temperature in the single crystal. The phase angle between the real and imaginary part of the dynamic response function changes drastically in the cubic and tetragonal phases and remains constant in the orthorhombic phase. Other phases show a moderate dependence of the phase angle on temperature showing systematic changes of twin microstructures. Mobile twin boundaries (or sections of twin boundaries such as kinks inside twin walls) contribute strongly to the energy dissipation of the forced oscillation while the reduction in effective modulus due to relaxing twin domains is weak. Single crystals and ceramics show strong precursor softening in the cubic phase related to polar nanoregions (PNRs). The effective modulus decreases when the transition point of the cubic-tetragonal transformation is approached from above. The precursor softening follows temperature dependence very similar to recent results from Brillouin scattering. Between the Burns temperature (≈586 K) and Tc at 405 K, we found a good fit of the squared RUS frequency [∼Δ (C11−C12)] to a Vogel–Fulcher process with an activation energy of ∼0.2 eV. Finally, some first-principles-based effective Hamiltonian computations were carried out in BaTiO3 single domains to explain some of these observations in terms of the dynamics of the soft mode and central mode.
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40. Middle Ear Mechanics in the Barn Owl.

Author: Peacock J, Benson MA, Field DJ, and Spellman GM
Abstract: The barn owl is a common research subject in auditory science due to its exceptional capacity for high frequency hearing and superb sound source localization capabilities. Despite longstanding interest in the auditory performance of barn owls, the function of its middle ear has attracted remarkably little attention. Here, we report the middle ear transfer function measured by laser Doppler vibrometry and direct measurements of inner ear pressures. Our results illustrate that the barn owl middle ear produces a pressure gain between the ear canal and the inner ear vestibule of up to 35 dB, which is comparable to that seen in mammals. The footplate velocity transfer function magnitudes overlap with those measured in other bird species, however the differences in phase between the footplate velocity and the sound pressure stimulus indicate a middle ear group delay that is notably shorter than other birds. This work brings us closer to a more complete understanding of the physiology of hearing in a model organism in auditory science., (© 2025 The Author(s). Journal of Morphology published by Wiley Periodicals LLC.)
Published: 2025
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41. The genomic and clinical consequences of replacing procarbazine with dacarbazine in escalated BEACOPP for Hodgkin lymphoma: a retrospective, observational study.

Author: Santarsieri A, Mitchell E, Pham MH, Sanghvi R, Jablonski J, Lee-Six H, Sturgess K, Brice P, Menne TF, Osborne W, Creasey T, Ardeshna KM, Baxter J, Behan S, Bhuller K, Booth S, Chavda ND, Collins GP, Culligan DJ, Cwynarski K, Davies A, Downing A, Dutton D, Furtado M, Gallop-Evans E, Hodson A, Hopkins D, Hsu H, Iyengar S, Jones SG, Karanth M, Linton KM, Lomas OC, Martinez-Calle N, Mathur A, McKay P, Nagumantry SK, Phillips EH, Phillips N, Rudge JF, Shah NK, Stafford G, Sternberg A, Trickey R, Uttenthal BJ, Wetherall N, Zhang XY, McMillan AK, Coleman N, Stratton MR, Laurenti E, Borchmann P, Borchmann S, Campbell PJ, Rahbari R, and Follows GA
Abstract: Background: Procarbazine-containing chemotherapy regimens are associated with cytopenias and infertility, suggesting stem-cell toxicity. When treating Hodgkin lymphoma, procarbazine in escalated-dose bleomycin-etoposide-doxorubicin-cyclophosphamide-vincristine-procarbazine-prednisolone (eBEACOPP) is increasingly replaced with dacarbazine (eBEACOPDac) to reduce toxicity. We aimed to investigate the impact of this drug substitution on the mutation burden in stem cells, patient survival, and toxicity., Methods: In this two-part retrospective, observational study, we first compared mutational landscapes in haematopoietic stem and progenitor cells (HSPCs) from patients with advanced-stage Hodgkin lymphoma in remission for at least 6 months who had been treated with eBEACOPDac (eBEACOPDac cohort), eBEACOPP (real-world eBEACOPP cohort), or doxorubicin-bleomycin-vinblastine-dacarbazine (ABVD); in buccal DNA from five children of a female patient with classical Hodgkin lymphoma treated with eBEACOPP before conceiving the third child; in sperm DNA from a patient with mild oligospermia treated with eBEACOPP; and in caecal adenocarcinoma and healthy colon tissue from a survivor of Hodgkin lymphoma treated with chlorambucil-vinblastine-procarbazine-prednisolone. For the second part, we analysed efficacy and toxicity data from adult patients (aged >16 years) treated with first-line eBEACOPDac (eBEACOPDac cohort) at 25 centres across UK, Ireland, and France; efficacy was compared with the German HD18 eBEACOPP trial data and toxicity with a UK real-world dataset. Participants in the German HD18 and UK real-world datasets were adults (aged >16 years) with previously untreated Hodgkin lymphoma, treated with first-line eBEACOPP. We had two co-primary objectives: to define the comparative stem-cell mutation burden and mutational signatures after treatment with or without procarbazine-containing chemotherapy (first study part); and to determine progression-free survival of patients with Hodgkin lymphoma treated with eBEACOPP or eBEACOPDac (second study part). Secondary objectives included overall survival and explored differences in specific toxicity outcomes, including transfusion requirements and measures of reproductive health (second study part)., Findings: In the first part of the study (mutational analysis), patients treated with eBEACOPP (n=5) exhibited a higher burden of point mutations in HSPCs compared with those treated with eBEACOPDac (n=4) or ABVD (n=3; excess mutations 1150 [95% CI 934-1366] vs 290 [241-339] vs 186 [116-254]). Two novel mutational signatures, SBSA (SBS25-like) and SBSB, were identified in HSPCs and in a single neoplastic and healthy colon sample from patients who received procarbazine-containing chemotherapy. SBSB was also identified in germline DNA of three children conceived after eBEACOPP and in sperm of a male patient treated with eBEACOPP. SBSC was detected in patients treated with either ABVD or eBEACOPDac. In the second part of the study (efficacy and toxicity analysis), dacarbazine substitution did not appear to compromise efficacy or safety. 312 patients treated with eBEACOPDac (eBEACOPDac cohort; treated 2017-22, 186 [60%] male, median follow-up 36·0 months [IQR 25·2-50·1]) had a 3-year progression-free survival of 93·3% (95% CI 90·3-96·4), which was similar to the 93·3% [95% CI 92·1-94·4]) progression-free survival seen in 1945 patients in the German HD18 eBEACOPP trial (treated 2008-14, 1183 [61%] male, median follow-up 57·0 months [35·4-64·7]). Patients treated with eBEACOPDac required fewer blood transfusions (mean 1·70 units [SD 2·77] vs 3·69 units [3·89]; p<0·0001), demonstrated higher post-chemotherapy sperm concentrations (median 23·4 million per mL [IQR 11·0-632·3] vs 0·0 million per mL [0·0-0·001]; p=0·0040), and had earlier resumption of menstrual periods (mean 5·04 months [SD 3·07] vs 8·77 months [5·57]; p=0·0036) compared with 73 patients treated with eBEACOPP in the UK real-world dataset., Interpretation: Procarbazine induces a higher mutation burden and novel mutational signatures in patients with Hodgkin lymphoma treated with eBEACOPP and their germline DNA, raising concerns for the genomic health of survivors of Hodgkin lymphoma and hereditary consequences for their offspring. However, replacing procarbazine with dacarbazine appears to mitigate gonadal and stem-cell toxicity while maintaining similar clinical efficacy., Funding: Addenbrooke's Charitable Trust and Wellcome Trust., Competing Interests: Declaration of interests AS reports support for meetings or conferences from Takeda. WO reports payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Roche, Takeda, Pfizer, Servier, Kite Gilead, MSD, Novartis, Beigene, AstraZeneca, Syneos, Autolus, Kywoa Kirin, AbbVie, Incyte, BMS, Janssen, and Sobi. GCP reports honoraria for speaker and advisory work from Takeda, Roche, Kite, AbbVie, Beigene, AstraZeneca, Sobi, and Secura Bio; and support for research from Beigene, Pfizer, BMS, Amgen, and AstraZeneca. DD reports speaker fees from AbbVie and support for travel to conferences from AstraZeneca and Beigene. PM reports support for meetings or conferences from Takeda. EHP reports honoraria for advisory work and support for meetings or conferences from Takeda. EL reports research support from CSL Behring. PB reports consulting fees from Takeda, BMS, Roche, Amgen, Novartis, Celgene, Miltenyi Biotech, and Gilead; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Takeda, Novartis, BMS, Roche, MSD, Celgene, Miltenyi Biotech, Gilead, and AbbVie; and funding for scientific research from Takeda Oncology, MSD, and Novartis. SB reports consulting fees from Galapagos; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events and consultation from Takeda; financial support for attending meetings or travel from Takeda; having a leadership role in another board, society, committee, or advocacy group (paid or unpaid), and holding stock or stock options for Liqomics. GAF reports honoraria for advisory work and support for meetings or conferences from Takeda. EM, MHP, RS, JJ, HLS, KS, PB, TFM, TC, KMA, JB, SB, KB, SB, NDC, DJC, KC, AD, AD, MF, EGE, AH, DH, HH, SI, SGJ, MK, KML, OCL, NMC, AM, SKN, NP, JFR, NKS, GS, AS, RT, BJU, NW, XYZ, AKM, NC, MRS, PJC, and RR declare no competing interests., (Copyright © 2025 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)
Published: 2025
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42. Exploring proteins within the coccolith matrix.

Author: Dedman CJ, Chauhan N, González-Lanchas A, Baldreki C, Dowle AA, Larson TR, Lee RBY, and Rickaby REM
Subjects: Algal Proteins metabolism, Calcification, Physiologic, Haptophyta metabolism, Calcium Carbonate metabolism, Calcium Carbonate chemistry
Abstract: Coccolithophores comprise a major component of the oceanic carbon cycle. These unicellular algae produce ornate structures made of calcium carbonate, termed coccoliths, representing ~ 50% of calcite production in the open ocean. The exact molecular mechanisms which direct and control coccolith formation are unknown. In this study, we report on the presence and functional features of proteins within the coccoliths produced by a range of model coccolithophore species including: the globally abundant and well-studied Gephyrocapsa huxleyi (formerly Emiliania huxleyi) and related Gephyrocapsa oceanica, as well as the larger and more heavily calcified Coccolithus braarudii. Protein features were compared between species and against biomineralisation proteins previously identified in other marine calcifying organisms. Notably, several protein features were consistently seen across the examined coccolithophore species, including the cell signalling 14-3-3 domain, chromosome segregation SMC ATPase domain, as well as proteins involved in protein processing and protease inhibition. The copper-binding cupredoxin domain was observed in both Gephyrocapsa species, as well as other marine calcifiers, suggestive of a requirement of Cu in biomineralisation. Building consensus with existing work, we highlight the pentapeptide repeat as a feature which is associated with the coccolith matrix, being identified in all three examined species, and propose that this structural motif may play a role in controlling coccolith growth. This preliminary study provides insight towards the functional diversity of calcification machinery in coccolithophores and presents a number of candidates for future research towards understanding the biochemical controls which direct coccolithogenesis., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)
Published: 2024
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43. Contrasting macroevolutionary patterns in pelagic tetrapods across the Triassic-Jurassic transition.

Author: Laboury A, Stubbs TL, Wolniewicz AS, Liu J, Scheyer TM, Jones MEH, and Fischer V
Subjects: Animals, Phylogeny, Biological Evolution, Fossils anatomy & histology, Reptiles anatomy & histology, Reptiles genetics, Reptiles classification, Body Size
Abstract: The iconic marine raptorial predators Ichthyosauria and Eosauropterygia co-existed in the same ecosystems throughout most of the Mesozoic Era, facing similar evolutionary pressures and environmental perturbations. Both groups seemingly went through a massive macroevolutionary bottleneck across the Triassic-Jurassic (T/J) transition that greatly reduced their morphological diversity, leaving pelagic lineages as the only survivors. However, analyses of marine reptile disparity across the T/J transition have usually employed coarse morphological and temporal data. We comprehensively compare the evolution of ichthyosaurian and eosauropterygian morphology and body size across the Middle Triassic to Early Jurassic interval and find contrasting macroevolutionary patterns. The ecomorphospace of eosauropterygians predominantly reflects a strong phylogenetic signal, resulting in the clustering of three clades with clearly distinct craniodental phenotypes, suggesting "leaps" toward novel feeding ecologies. Ichthyosaurian diversification lacks a discernible evolutionary trend, as we find evidence for a wide overlap of craniodental morphologies between Triassic and Early Jurassic forms. The temporal evolution of ecomorphological disparity, fin shape and body size of eosauropterygians and ichthyosaurians during the Late Triassic does not support the hypothesis of an abrupt macroevolutionary bottleneck near the T/J transition. Rather, an important turnover event should be sought earlier, during times of rapid sea level falls., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE). All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
Published: 2024
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44. Reinterpretation of Report of Tetrataenite in Bulk Alloy Castings.

Author: Houghton OS, Loudon JC, Twitchett-Harrison AC, Panagiotopoulos NT, Lampronti GI, Costa MB, Harrison RJ, and Greer AL
Abstract: After the publication of "Direct formation of hard-magnetic tetrataenite in bulk alloy castings" Ivanov et al., Advanced Science 10 (2022) 2204315, the authors identified a potential misinterpretation of the experimental data. Further work confirms that the original conclusions cannot be supported, and accordingly the paper is retracted. X-ray diffraction shows the presence of (Fe,Ni) 3 P, giving additional Bragg peaks that were previously attributed to tetrataenite. Extra Bragg reflections observed in transmission electron diffraction, and earlier considered to be superlattice reflections from tetrataenite, instead result from oxidation of the sample surface during preparation. Measurements of magnetic hysteresis show no regions of high coercivity of the kind expected when tetrataenite is present. It is concluded that as-cast bulk samples of Fe-Ni-P-(C) show no evidence of tetrataenite on any length scale. Nevertheless, the addition of phosphorus should remain of interest in ongoing efforts to manufacture tetrataenite., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)
Published: 2024
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45. Distribution theories for genetic line of least resistance and evolvability measures.

Author: Watanabe J
Subjects: Genetic Variation, Models, Genetic, Biological Evolution, Selection, Genetic
Abstract: Quantitative genetic theory on multivariate character evolution predicts that a population's response to directional selection is biased towards the major axis of the genetic covariance matrix G-the so-called genetic line of least resistance. Inferences on the genetic constraints in this sense have traditionally been made by measuring the angle of deviation of evolutionary trajectories from the major axis or, more recently, by calculating the amount of genetic variance-the Hansen-Houle evolvability-available along the trajectories. However, there have not been clear practical guidelines on how these quantities can be interpreted, especially in a high-dimensional space. This study summarizes pertinent distribution theories for relevant quantities, pointing out that they can be written as ratios of quadratic forms in evolutionary trajectory vectors by taking G as a parameter. For example, a beta distribution with appropriate parameters can be used as a null distribution for the squared cosine of the angle of deviation from a major axis or subspace. More general cases can be handled with the probability distribution of ratios of quadratic forms in normal variables. Apart from its use in hypothesis testing, this latter approach could potentially be used as a heuristic tool for looking into various selection scenarios, like directional and/or correlated selection, as parameterized with the mean and covariance of selection gradients., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology.)
Published: 2024
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46. Contrasting species-specific stress response to environmental pH determines the fate of coccolithophores in future oceans.

Author: Chauhan N, Dedman CJ, Baldreki C, Dowle AA, Larson TR, and Rickaby REM
Subjects: Hydrogen-Ion Concentration, Haptophyta, Seawater chemistry, Stress, Physiological, Species Specificity, Oxidative Stress, Photosynthesis, Oceans and Seas
Abstract: Molecular mechanisms driving species-specific environmental sensitivity in coccolithophores are unclear but crucial in understanding species selection and adaptation to environmental change. This study examined proteomic and physiological changes in three species under varying pH conditions. We showed that changing pH drives intracellular oxidative stress and changes membrane potential. Upregulation in antioxidant, DNA repair and cell cycle-related protein-groups indicated oxidative damage across high (pH 8.8) and low pH (pH 7.6) compared to control pH (pH 8.2), and correlated with reduced growth rates. Upregulation of mitochondrial proteins suggested higher metabolite demand for restoring cellular homeostasis under pH-induced stress. Photosynthetic rates generally correlated with CO 2 availability, driving higher net carbon fixation rates at low pH. The intracellular pH-buffering capacity of the coastal Chrysotila carterae and high metabolic adaptability in the bloom-forming Gephyrocapsa huxleyi will likely facilitate their adaptation to ocean acidification or artificial ocean alkalinisation. However, the pH sensitivity of the ancient open-ocean Coccolithus braarudii will possibly result in reduced growth and shrinking of its ecological niche., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)
Published: 2024
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47. Evolution of Large Eyes in Stromboidea (Gastropoda): Impact of Photic Environment and Life History Traits.

Author: Irwin AR, Roberts NW, Strong EE, Kano Y, Speiser DI, Harper EM, and Williams ST
Abstract: Eyes within the marine gastropod superfamily Stromboidea range widely in size, from 0.2 to 2.3 mm - the largest eyes known in any gastropod. Despite this interesting variation, the underlying evolutionary pressures remain unknown. Here, we use the wealth of material available in museum collections to explore the evolution of stromboid eye size and structure. Our results suggest that depth is a key light-limiting factor in stromboid eye evolution; here, increasing water depth is correlated with increasing aperture width relative to lens diameter, and therefore an increasing investment in sensitivity in dim light environments. In the major clade containing all large-eyed stromboid families, species observed active during the day and the night had wider eye apertures relative to lens sizes than species observed active during the day only, thereby prioritising sensitivity over resolution. Species with no consistent diel activity pattern also had smaller body sizes than exclusively day-active species, which may suggest that smaller animals are more vulnerable to shell-crushing predators, and avoid the higher predation pressure experienced by animals active during the day. Within the same major clade, ancestral state reconstruction suggests that absolute eye size increased above 1 mm twice. The unresolved position of Varicospira, however, weakens this hypothesis and further work with additional markers is needed to confirm this result., (© The Author(s) 2024. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
Published: 2024
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48. Upper bill bending as an adaptation for nectar feeding in hummingbirds.

Author: Rico-Guevara A, Sustaita D, Hurme KJ, Hanna JE, Jung S, and Field DJ
Subjects: Animals, Biomechanical Phenomena, Adaptation, Physiological physiology, Birds physiology, Birds anatomy & histology, Plant Nectar, Beak anatomy & histology, Beak physiology, Feeding Behavior physiology
Abstract: Observations of maxillary (upper bill) bending in hummingbirds have been considered an optical illusion, yet a recent description of out-of-phase opening and closing between their bill base and tip suggests a genuine capacity for bill bending. We investigate bill kinematics during nectar feeding in six species of hummingbirds. We employed geometric morphometrics to identify bending zones and combined these data with measurements of bill flexural rigidity from micro-computed tomography scans to better understand the flexing mechanism. We found that the mandible remains in place throughout the licking cycle, while the maxilla undergoes significant shape deformation, such that the distal portion of the upper bill bends upwards. We propose that bill bending is a key component of the drinking mechanism in hummingbirds, allowing the coordination of bill function (distal wringing and basal expansion) and tongue function (raking/squeegeeing) during intra-oral transport. We present a fluid analysis that reveals a combination of pressure-driven (Poiseuille) and boundary-driven (Couette) flows, which have previously been thought to represent alternative drinking mechanisms. Bill bending allows for separation of the bill tips while maintaining a tightly closed middle section of the bill, enabling nectar exploitation in long and narrow flowers that can exclude less efficient pollinators.
Published: 2024
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49. Cretaceous bird from Brazil informs the evolution of the avian skull and brain.

Author: Chiappe LM, Navalón G, Martinelli AG, Carvalho IS, Miloni Santucci R, Wu YH, and Field DJ
Subjects: Animals, Brazil, Phylogeny, Cerebellum anatomy & histology, Telencephalon anatomy & histology, Neuroanatomy, Biological Evolution, Birds anatomy & histology, Birds classification, Brain anatomy & histology, Fossils, Skull anatomy & histology
Abstract: A dearth of Mesozoic-aged, three-dimensional fossils hinders understanding of the origin of the distinctive skull and brain of modern (crown) birds 1 . Here we report Navaornis hestiae gen. et sp. nov., an exquisitely preserved fossil species from the Late Cretaceous of Brazil. The skull of Navaornis is toothless and large-eyed, with a vaulted cranium closely resembling the condition in crown birds; however, phylogenetic analyses recover Navaornis in Enantiornithes, a highly diverse clade of Mesozoic stem birds. Despite an overall geometry quantitatively indistinguishable from crown birds, the skull of Navaornis retains numerous plesiomorphies including a maxilla-dominated rostrum, an akinetic palate, a diapsid temporal configuration, a small cerebellum and a weakly expanded telencephalon. These archaic neurocranial traits are combined with a crown bird-like degree of brain flexion and a bony labyrinth comparable in shape to those of many crown birds but substantially larger. Altogether, the emergent cranial geometry of Navaornis shows an unprecedented degree of similarity between crown birds and enantiornithines, groups last sharing a common ancestor more than 130 million years ago 2 . Navaornis provides long-sought insight into the detailed cranial and endocranial morphology of stem birds phylogenetically crownward of Archaeopteryx, clarifying the pattern and timing by which the distinctive neuroanatomy of living birds was assembled., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s).)
Published: 2024
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50. Identifying signatures of the earliest benthic bulldozers in emergent subaerial conditions during the colonization of land by animals.

Author: Wang Z, Davies NS, Liu AG, Minter NJ, and Rahman IA
Subjects: Animals, Mollusca physiology, Biological Evolution, Ecosystem, Geologic Sediments, Fossils
Abstract: The colonization of land by animals was a milestone in the history of life. Approximately 100 million years before full terrestrialization, early animals sporadically traversed emergent subaerial substrates, leaving behind trace fossils recording their activities. However, identifying temporarily emergent environments and determining the affinities, motility and subaerial endurance of the trace-makers, and the timing and magnitude of their impacts on marginal-marine environments, are challenging. Here, we used semi-resolved computational fluid dynamics-discrete element method coupling to simulate trace formation on non-cohesive sediments in submerged and emergent subaerial conditions. This revealed instability-induced morphological signatures that allow us to identify the earliest terrestrial trace fossils. Quantitative metrics enable us to infer that the putative earliest terrestrial trace-makers were molluscs, and dimensional analysis suggests that their subaerial excursions could last at least 15 min. These organisms navigated emergent environments from the early Cambrian (stage 2), tens of millions of years earlier than arthropods. This quantitative paradigm provides new insights into the palaeobiology of the earliest subaerial bulldozers and highlights that mollusc-like animals were among the first ecosystem engineers to enter marginal-marine settings. They may thus have contributed to the establishment of marginal-marine biogeochemical cycles, laying the groundwork for subsequent terrestrialization by other animals.
Published: 2024
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