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2. Extreme redox variations in a superdeep diamond from a subducted slab

Author

Fabrizio Nestola, Margo E. Regier, Robert W. Luth, D. Graham Pearson, Thomas Stachel, Catherine McCammon, Michelle D. Wenz, Steven D. Jacobsen, Chiara Anzolini, Luca Bindi, and Jeffrey W. Harris

Subjects
Heating, Multidisciplinary, Dehydration, Humans, Chemical Fractionation, Diamond, Oxidation-Reduction
Abstract

The introduction of volatile-rich subducting slabs to the mantle may locally generate large redox gradients, affecting phase stability, element partitioning and volatile speciation

Published
2023
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3. Extreme redox variations in a superdeep diamond from a subducted slab

Author

Nestola, Fabrizio, primary, Regier, Margo E., additional, Luth, Robert W., additional, Pearson, D. Graham, additional, Stachel, Thomas, additional, McCammon, Catherine, additional, Wenz, Michelle D., additional, Jacobsen, Steven D., additional, Anzolini, Chiara, additional, Bindi, Luca, additional, and Harris, Jeffrey W., additional

Published
2023
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4. Observation of two-neutrino double electron capture in 124Xe with XENON1T

Author

Aprile, E., Aalbers, J., Agostini, F., Alfonsi, M., Althueser, L., Amaro, F. D., Anthony, M., Antochi, V. C., Arneodo, F., Baudis, L., Bauermeister, B., Benabderrahmane, M. L., Berger, T., Breur, P. A., Brown, A., Brown, E., Bruenner, S., Bruno, G., Budnik, R., Capelli, C., Cardoso, J. M. R., Cichon, D., Coderre, D., Colijn, A. P., Conrad, J., Cussonneau, J. P., Decowski, M. P., de Perio, P., di Gangi, P., di Giovanni, A., Diglio, S., Elykov, A., Eurin, G., Fei, J., Ferella, A. D., Fieguth, A., FULGIONE, VALTER, Gallo Rosso, A., Galloway, M., Gao, F., Garbini, M., Grandi, L., Greene, Z., Hasterok, C., Hogenbirk, E., Howlett, J., Iacovacci, M., Itay, R., Joerg, F., Kaminsky, B., Kazama, S., Kish, A., Koltman, G., Kopec, A., Landsman, H., Lang, R. F., Levinson, L., Lin, Q., Lindemann, S., Lindner, M., Lombardi, F., Lopes, J. A. M., López Fune, E., Macolino, C., Mahlstedt, J., Manfredini, A., Marignetti, F., Marrodán Undagoitia, T., Masbou, J., Masson, D., Mastroianni, S., Messina, M., Micheneau, K., Miller, K., Molinario, A., Morå, K., Murra, M., Naganoma, J., Ni, K., Oberlack, U., Odgers, K., Pelssers, B., Peres, R., Piastra, F., Pienaar, J., Pizzella, V., Plante, G., Podviianiuk, R., Priel, N., Qiu, H., Ramírez García, D., Reichard, S., Riedel, B., Rizzo, A., Rocchetti, A., Rupp, N., Dos Santos, J. M. F., Sartorelli, G., Šarčević, N., Scheibelhut, M., Schindler, S., Schreiner, J., Schulte, D., Schumann, M., Scotto Lavina, L., Selvi, M., Shagin, P., Shockley, E., Silva, M., Simgen, H., Therreau, C., Thers, D., Toschi, F., TRINCHERO, GIAN CARLO, Tunnell, C., Upole, N., Vargas, M., Wack, O., Wang, H., Wang, Z., Wei, Y., Weinheimer, C., Wenz, D., Wittweg, C., Wulf, J., Ye, J., Zhang, Y., Zhu, T., Zopounidis, J. P., XENON (IHEF, IoP, FNWI), Aprile, E., Aalbers, J., Agostini, F., Alfonsi, M., Althueser, L., Amaro, F. D., Anthony, M., Antochi, V. C., Arneodo, F., Baudis, L., Bauermeister2, B., Benabderrahmane, M. L., Berger, T., Breur, P. A., Brown, A., Brown, E., Bruenner, S., Bruno, G., Budnik, R., Capelli, C., Cardoso, J. M. R., Cichon, D., Coderre, D., Colijn, A. P., Conrad, J., Cussonneau, J. P., Decowski, M. P., de Perio, P., Di Gangi, P., Di Giovanni, A., Diglio, S., Elykov, A., Eurin, G., Fei, J., Ferella, A. D., Fieguth, A., Fulgione, W., Gallo Rosso, A., Galloway, M., Gao, F., Garbini, M., Grandi, L., Greene, Z., Hasterok, C., Hogenbirk, E., Howlett, J., Iacovacci, M., Itay, R., Joerg, F., Kaminsky, B., Kazama, S., Kish, A., Koltman, G., Kopec, A., Landsman, H., Lang, R. F., Levinson, L., Lin, Q., Lindemann, S., Lindner, M., Lombardi, F., Lopes, J. A. M., López Fune, E., Macolino, C., Mahlstedt, J., Manfredini, A., Marignetti, F., Marrodán Undagoitia, T., Masbou, J., Masson, D., Mastroianni, S., Messina, M., Micheneau, K., Miller, K., Molinario, A., Morå, K., Murra, M., Naganoma, J., Ni, K., Oberlack, U., Odgers, K., Pelssers, B., Peres, R., Piastra, F., Pienaar, J., Pizzella, V., Plante, G., Podviianiuk, R., Priel, N., Qiu, H., Ramírez García, D., Reichard, S., Riedel, B., Rizzo, A., Rocchetti, A., Rupp, N., dos Santos, J. M. F., Sartorelli, G., Šarčević, N., Scheibelhut, M., Schindler, S., Schreiner, J., Schulte, D., Schumann, M., Scotto Lavina, L., Selvi, M., Shagin, P., Shockley, E., Silva, M., Simgen, H., Therreau, C., Thers, D., Toschi, F., Trinchero, G., Tunnell, C., Upole, N., Vargas, M., Wack, O., Wang, H., Wang, Z., Wei, Y., Weinheimer, C., Wenz, D., Wittweg, C., Wulf, J., Ye, J., Zhang, Y., Zhu &amp, T., Zopounidis, J. P., E. Aprile, J. Aalbers, F. Agostini, M. Alfonsi, L. Althueser, F. D. Amaro, M. Anthony, V. C. Antochi, F. Arneodo, L. Baudis, B. Bauermeister, M. L. Benabderrahmane, T. Berger, P. A. Breur, A. Brown, A. Brown, E. Brown, S. Bruenner, G. Bruno, R. Budnik, C. Capelli, J. M. R. Cardoso, D. Cichon, D. Coderre, A. P. Colijn, J. Conrad, J. P. Cussonneau, M. P. Decowski, P. de Perio, P. Di Gangi, A. Di Giovanni, S. Diglio, A. Elykov, G. Eurin, J. Fei, A. D. Ferella, A. Fieguth, W. Fulgione, A. Gallo Rosso, M. Galloway, F. Gao, M. Garbini, L. Grandi, Z. Greene, C. Hasterok, E. Hogenbirk, J. Howlett, M. Iacovacci, R. Itay, F. Joerg, B. Kaminsky, S. Kazama, A. Kish, G. Koltman, A. Kopec, H. Landsman, R. F. Lang, L. Levinson, Q. Lin, S. Lindemann, M. Lindner, F. Lombardi, J. A. M. Lopes, E. López Fune, C. Macolino, J. Mahlstedt, A. Manfredini, F. Marignetti, T. Marrodán Undagoitia, J. Masbou, D. Masson, S. Mastroianni, M. Messina, K. Micheneau, K. Miller, A. Molinario, K. Morå, M. Murra, J. Naganoma, K. Ni, U. Oberlack, K. Odgers, B. Pelssers, R. Peres, F. Piastra, J. Pienaar, V. Pizzella, G. Plante, R. Podviianiuk, N. Priel, H. Qiu, D. Ramírez García, S. Reichard, B. Riedel, A. Rizzo, A. Rocchetti, N. Rupp, J. M. F. dos Santos, G. Sartorelli, N. Šarčević, M. Scheibelhut, S. Schindler, J. Schreiner, D. Schulte, M. Schumann, L. Scotto Lavina, M. Selvi, P. Shagin, E. Shockley, M. Silva, H. Simgen, C. Therreau, D. Thers, F. Toschi, G. Trinchero, C. Tunnell, N. Upole, M. Vargas, O. Wack, H. Wang, Z. Wang, Y. Wei, C. Weinheimer, D. Wenz, C. Wittweg, J. Wulf, J. Ye, Y. Zhang, T. Zhu & J. P. Zopounidis, Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Accélérateur Linéaire (LAL), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), XENON, Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique)

Subjects
electron, Particle physics, Xenon, half-life, Age of the universe, Electron capture, Dark matter, background: model, chemistry.chemical_element, FOS: Physical sciences, electron: capture, n: thermal, 7. Clean energy, 01 natural sciences, weak process, background: low, Neutrino, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, S076H2N, Physics, xenon: liquid, Multidisciplinary, Isotope, 010308 nuclear & particles physics, iodine, neutrino: Majorana: mass, higher-order: 2, Nuclear structure, double-beta decay, dark matter: detector, energy: calibration, Neutrino, Xenon, half-life, electron, double electron capture, weak process, double electron capture, Orders of magnitude (time), chemistry, Dark Matter detector Electron Capture Low Background Double Beta Decay, xenon: nuclide, target: mass, numerical calculations: Monte Carlo, energy spectrum: measured, statistical, acceptance
Abstract

International audience; Two-neutrino double electron capture (2νECEC) is a second-order weak-interaction process with a predicted half-life that surpasses the age of the Universe by many orders of magnitude1. Until now, indications of 2νECEC decays have only been seen for two isotopes2,3,4,5, 78Kr and 130Ba, and instruments with very low background levels are needed to detect them directly with high statistical significance6,7. The 2νECEC half-life is an important observable for nuclear structure models8,9,10,11,12,13,14 and its measurement represents a meaningful step in the search for neutrinoless double electron capture—the detection of which would establish the Majorana nature of the neutrino and would give access to the absolute neutrino mass15,16,17. Here we report the direct observation of 2νECEC in 124Xe with the XENON1T dark-matter detector. The significance of the signal is 4.4 standard deviations and the corresponding half-life of 1.8 × 1022 years (statistical uncertainty, 0.5 × 1022 years; systematic uncertainty, 0.1 × 1022 years) is the longest measured directly so far. This study demonstrates that the low background and large target mass of xenon-based dark-matter detectors make them well suited for measuring rare processes and highlights the broad physics reach of larger next-generation experiments18,19,20.

Published
2019
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6. Structure of the mitochondrial import gate reveals distinct preprotein paths

Author

Toshio Ando, Kaori Yunoki, Yuhei Araiso, Jian Qiu, Lena-Sophie Wenz, Caroline Lindau, Nils Wiedemann, Akihisa Tsutsumi, Shin Kawano, Thomas Becker, Marilena Wischnewski, Takuya Shiota, Trevor Lithgow, Jiyao Song, Junko Suzuki, Masahide Kikkawa, Conny Schütze, Toshiya Endo, Hirotaka Ariyama, Haruka Sakaue, Kenichiro Imai, and Nikolaus Pfanner

Subjects
0303 health sciences, Multidisciplinary, biology, Dimer, Transmembrane protein, Yeast, Cell biology, 03 medical and health sciences, chemistry.chemical_compound, 0302 clinical medicine, chemistry, biology.protein, Translocase, Binding site, Bacterial outer membrane, 030217 neurology & neurosurgery, Biogenesis, Alpha helix, 030304 developmental biology
Abstract

The translocase of the outer mitochondrial membrane (TOM) is the main entry gate for proteins1–4. Here we use cryo-electron microscopy to report the structure of the yeast TOM core complex5–9 at 3.8-A resolution. The structure reveals the high-resolution architecture of the translocator consisting of two Tom40 β-barrel channels and α-helical transmembrane subunits, providing insight into critical features that are conserved in all eukaryotes1–3. Each Tom40 β-barrel is surrounded by small TOM subunits, and tethered by two Tom22 subunits and one phospholipid. The N-terminal extension of Tom40 forms a helix inside the channel; mutational analysis reveals its dual role in early and late steps in the biogenesis of intermembrane-space proteins in cooperation with Tom5. Each Tom40 channel possesses two precursor exit sites. Tom22, Tom40 and Tom7 guide presequence-containing preproteins to the exit in the middle of the dimer, whereas Tom5 and the Tom40 N extension guide preproteins lacking a presequence to the exit at the periphery of the dimer. The high-resolution cryo-electron microscopy structure of the yeast translocase of the outer mitochondrial membrane reveals key features of mitochondrial protein import that are conserved in all eukaryotes.

Published
2019
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7. The effect of rainfall changes on economic production

Author

Leonie Wenz, Maximilian Kotz, and Anders Levermann

Subjects
Multidisciplinary, Climate Change
Abstract

Macro-economic assessments of climate impacts lack an analysis of the distribution of daily rainfall, which can resolve both complex societal impact channels and anthropogenically forced changes

Published
2021

8. Mitochondrial sorting and assembly machinery operates by β-barrel switching

Author

Hironori, Takeda, Akihisa, Tsutsumi, Tomohiro, Nishizawa, Caroline, Lindau, Jon V, Busto, Lena-Sophie, Wenz, Lars, Ellenrieder, Kenichiro, Imai, Sebastian P, Straub, Waltraut, Mossmann, Jian, Qiu, Yu, Yamamori, Kentaro, Tomii, Junko, Suzuki, Takeshi, Murata, Satoshi, Ogasawara, Osamu, Nureki, Thomas, Becker, Nikolaus, Pfanner, Nils, Wiedemann, Masahide, Kikkawa, and Toshiya, Endo

Subjects
Mitochondrial Proteins, Models, Molecular, Protein Subunits, Saccharomyces cerevisiae Proteins, Multiprotein Complexes, Cryoelectron Microscopy, Membrane Proteins, Saccharomyces cerevisiae, Protein Multimerization, Mitochondria
Abstract

The mitochondrial outer membrane contains so-called β-barrel proteins, which allow communication between the cytosol and the mitochondrial interior

Published
2020

9. T-cell invigoration to tumour burden ratio associated with anti-PD-1 response

Author

Huang, Alexander C., Postow, Michael A., Orlowski, Robert J., Mick, Rosemarie, Bengsch, Bertram, Manne, Sasikanth, Xu, Wei, Harmon, Shannon, Giles, Josephine R., Wenz, Brandon, Adamow, Matthew, Kuk, Deborah, Panageas, Katherine S., Carrera, Cristina, Wong, Phillip, Quagliarello, Felix, Wubbenhorst, Bradley, DAndrea, Kurt, Pauken, Kristen E., Herati, Ramin S., Staupe, Ryan P., Schenkel, Jason M., McGettigan, Suzanne, Kothari, Shawn, George, Sangeeth M., Vonderheide, Robert H., Amaravadi, Ravi K., Karakousis, Giorgos C., Schuchter, Lynn M., Xu, Xiaowei, Nathanson, Katherine L., Wolchok, Jedd D., Gangadhar, Tara C., and Wherry, E. John

Subjects
Apoptosis -- Research, Cancer research, Tumors -- Physiological aspects, Melanoma -- Physiological aspects, T cells -- Physiological aspects, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Despite the success of monotherapies based on blockade of programmed cell death 1 (PD-1) in human melanoma, most patients do not experience durable clinical benefit. Pre-existing T-cell infiltration and/or the presence of PD-L1 in tumours may be used as indicators of clinical response; however, blood-based profiling to understand the mechanisms of PD-1 blockade has not been widely explored. Here we use immune profiling of peripheral blood from patients with stage IV melanoma before and after treatment with the PD-1-targeting antibody pembrolizumab and identify pharmacodynamic changes in circulating exhausted-phenotype CD8 T cells (T[sub.ex] cells). Most of the patients demonstrated an immunological response to pembrolizumab. Clinical failure in many patients was not solely due to an inability to induce immune reinvigoration, but rather resulted from an imbalance between T-cell reinvigoration and tumour burden. The magnitude of reinvigoration of circulating T[sub.ex] cells determined in relation to pretreatment tumour burden correlated with clinical response. By focused profiling of a mechanistically relevant circulating T-cell subpopulation calibrated to pretreatment disease burden, we identify a clinically accessible potential on-treatment predictor of response to PD-1 blockade., Author(s): Alexander C. Huang (corresponding author) [1, 2, 3, 4]; Michael A. Postow [5, 6]; Robert J. Orlowski [1, 2, 3, 4]; Rosemarie Mick [3, 4, 7]; Bertram Bengsch [2, [...]

Published
2017
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10. Mitochondrial sorting and assembly machinery operates by β-barrel switching

Author

Takeda, Hironori, primary, Tsutsumi, Akihisa, additional, Nishizawa, Tomohiro, additional, Lindau, Caroline, additional, Busto, Jon V., additional, Wenz, Lena-Sophie, additional, Ellenrieder, Lars, additional, Imai, Kenichiro, additional, Straub, Sebastian P., additional, Mossmann, Waltraut, additional, Qiu, Jian, additional, Yamamori, Yu, additional, Tomii, Kentaro, additional, Suzuki, Junko, additional, Murata, Takeshi, additional, Ogasawara, Satoshi, additional, Nureki, Osamu, additional, Becker, Thomas, additional, Pfanner, Nikolaus, additional, Wiedemann, Nils, additional, Kikkawa, Masahide, additional, and Endo, Toshiya, additional

Published
2021
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12. Structure of the mitochondrial import gate reveals distinct preprotein paths

Author

Araiso, Yuhei, Tsutsumi, Akihisa, Qiu, Jian, Imai, Kenichiro, Shiota, Takuya, Song, Jiyao, Lindau, Caroline, Wenz, Lena-Sophie, Sakaue, Haruka, Yunoki, Kaori, Kawano, Shin, Suzuki, Junko, Wischnewski, Marilena, Schutze, Conny, Ariyama, Hirotaka, Ando, Toshio, Becker, Thomas, Lithgow, Trevor, Wiedemann, Nils, Pfanner, Nikolaus, Kikkawa, Masahide, and Endo, Toshiya

Subjects
Models, Molecular, Saccharomyces cerevisiae Proteins, receptor, Cryoelectron Microscopy, channel, translocation, Saccharomyces cerevisiae, system, outer-membrane, Mitochondrial Membrane Transport Proteins, intermembrane-space domain, Mitochondria, presequence, Mitochondrial Precursor Protein Import Complex Proteins, tom core complex, protein import, Protein Multimerization, Phospholipids, binding-site
Abstract

The translocase of the outer mitochondrial membrane (TOM) is the main entry gate for proteins(1-4). Here we use cryo-electron microscopy to report the structure of the yeast TOM core complex(5-9) at 3.8-angstrom resolution. The structure reveals the high-resolution architecture of the translocator consisting of two Tom40 beta-barrel channels and a-helical transmembrane subunits, providing insight into critical features that are conserved in all eukaryotes(1-3). Each Tom40 beta-barrel is surrounded by small TOM subunits, and tethered by two Tom22 subunits and one phospholipid. The N-terminal extension of Tom40 forms a helix inside the channel; mutational analysis reveals its dual role in early and late steps in the biogenesis of intermembrane-space proteins in cooperation with Tom5. Each Tom40 channel possesses two precursor exit sites. Tom22, Tom40 and Tom7 guide presequence-containing preproteins to the exit in the middle of the dimer, whereas Tom5 and the Tom40 N extension guide preproteins lacking a presequence to the exit at the periphery of the dimer.

Published
2019

16. Formula 1 racing: Science in the FAST LANE

Author

Ziemelis, Karl and Wenz, Charles

Subjects
Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Author(s): Karl Ziemelis [1]; Charles Wenz [1] [illus. 1] Christine Lear's secret is out. As a practical girl, she chose a practical career path, one that suited well her university [...]

Published
2004
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17. T-cell invigoration to tumour burden ratio associated with anti-PD-1 response

Author

Ramin S. Herati, Bradley Wubbenhorst, Jason M. Schenkel, Robert H. Vonderheide, Kurt D'Andrea, Shannon Harmon, Shawn Kothari, Felix Quagliarello, Michael A. Postow, Brandon Wenz, Katherine L. Nathanson, Ravi K. Amaravadi, Lynn M. Schuchter, Robert J. Orlowski, E. John Wherry, Matthew Adamow, Sasikanth Manne, Phillip Wong, Alexander C. Huang, Josephine R. Giles, Wei Xu, Suzanne McGettigan, Deborah Kuk, Giorgos C. Karakousis, Katherine S. Panageas, Cristina Carrera, Bertram Bengsch, Sangeeth M. George, Tara C. Gangadhar, Rosemarie Mick, Xiaowei Xu, Jedd D. Wolchok, Kristen E. Pauken, and Ryan P. Staupe

Subjects
Male, medicine.medical_treatment, T cell, Programmed Cell Death 1 Receptor, Pembrolizumab, CD8-Positive T-Lymphocytes, Antibodies, Monoclonal, Humanized, Article, 03 medical and health sciences, 0302 clinical medicine, Immune system, Medicine, Cytotoxic T cell, Humans, Melanoma, Neoplasm Staging, Multidisciplinary, business.industry, Immunotherapy, medicine.disease, Blockade, Tumor Burden, medicine.anatomical_structure, Ki-67 Antigen, Phenotype, Treatment Outcome, 030220 oncology & carcinogenesis, Monoclonal, Immunology, Female, business, 030215 immunology
Abstract

Despite the success of monotherapies based on blockade of programmed cell death 1 (PD-1) in human melanoma, most patients do not experience durable clinical benefit. Pre-existing T-cell infiltration and/or the presence of PD-L1 in tumours may be used as indicators of clinical response; however, blood-based profiling to understand the mechanisms of PD-1 blockade has not been widely explored. Here we use immune profiling of peripheral blood from patients with stage IV melanoma before and after treatment with the PD-1-targeting antibody pembrolizumab and identify pharmacodynamic changes in circulating exhausted-phenotype CD8 T cells (Tex cells). Most of the patients demonstrated an immunological response to pembrolizumab. Clinical failure in many patients was not solely due to an inability to induce immune reinvigoration, but rather resulted from an imbalance between T-cell reinvigoration and tumour burden. The magnitude of reinvigoration of circulating Tex cells determined in relation to pretreatment tumour burden correlated with clinical response. By focused profiling of a mechanistically relevant circulating T-cell subpopulation calibrated to pretreatment disease burden, we identify a clinically accessible potential on-treatment predictor of response to PD-1 blockade.

Published
2016

18. A single sub-kilometre Kuiper belt object from a stellar occultation in archival data

Author

Edmund P. Nelan, Eran O. Ofek, Avishay Gal-Yam, Shay Zucker, Michael Wenz, Hilke E. Schlichting, Mario Livio, and Ramazan Sari

Subjects
Physics, Earth and Planetary Astrophysics (astro-ph.EP), Solar System, Multidisciplinary, Dwarf planet, Haumea, Astronomical unit, Astronomy, FOS: Physical sciences, Astrophysics, Accretion (astrophysics), Pluto, Minor-planet moon, Astrophysics - Solar and Stellar Astrophysics, Neptune, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

The Kuiper belt is a remnant of the primordial Solar System. Measurements of its size distribution constrain its accretion and collisional history, and the importance of material strength of Kuiper belt objects (KBOs). Small, sub-km sized, KBOs elude direct detection, but the signature of their occultations of background stars should be detectable. Observations at both optical and X-ray wavelengths claim to have detected such occultations, but their implied KBO abundances are inconsistent with each other and far exceed theoretical expectations. Here, we report an analysis of archival data that reveals an occultation by a body with a 500 m radius at a distance of 45 AU. The probability of this event to occur due to random statistical fluctuations within our data set is about 2%. Our survey yields a surface density of KBOs with radii larger than 250 m of 2.1^{+4.8}_{-1.7} x 10^7 deg^{-2}, ruling out inferred surface densities from previous claimed detections by more than 5 sigma. The fact that we detected only one event, firmly shows a deficit of sub-km sized KBOs compared to a population extrapolated from objects with r>50 km. This implies that sub-km sized KBOs are undergoing collisional erosion, just like debris disks observed around other stars., To appear in Nature on December 17, 2009. Under press embargo until 1800 hours London time on 16 December. 19 pages; 7 figures

Published
2009

20. Vine work

Author

Wenz, Charles

Subjects
Red wines -- Origin, Grapes -- Genetic aspects, Environmental issues, Science and technology, Zoology and wildlife conservation, Origin, Genetic aspects
Abstract

The draft genome sequence of Vitis vinifera, the grapevine, described in this issue, provides plenty of scope for discussion over a glass of its fermented product. The sequence was published [...]

Published
2007

21. Vine work

Author

Charles Wenz

Subjects
Whole genome sequencing, Crop, Vine, Multidisciplinary, Botany, Gene duplication, Genomics, Flowering plant, Biology, biology.organism_classification, Woody plant, Sequence (medicine)
Abstract

The fourth genome sequence of a flowering plant, the second of a woody plant species and the first for a fruit crop. These important boxes are ticked by the genome sequence published in this issue. The new sequence is particularly revealing about the role of gene duplication in the evolution of the flowering plants. But the reason why non-geneticists will turn to it is more to do with its commercial application: the crop is the grapevine (Vitis vinifera) and the variety is Pinot Noir.

Published
2007
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24. Geochemical evidence for invasion of Kilauea's plumbing system by Mauna Loa magma

Author

K. P. Wenz, J. W. Sparks, J. M. Rhodes, John P. Lockwood, and Christina A. Neal

Subjects
geography, Multidisciplinary, geography.geographical_feature_category, Volcano, Lava, Geochemistry, Volcanism, Mantle (geology), Geology, Upward migration
Abstract

From the beginning of the study of Hawaiian volcanism there has been controversy over possible relationships between the neighbouring active volcanoes Mauna Loa and Kilauea1–5. Seismic activity, thought to reflect upward migration of magma, reveals that the magmatic plumbing systems apparently converge at depth to form a broad funnel within the mantle6. Although on rare occasions they have erupted concurrently, the brief historical eruptive record appears to show that when Kilauea is most active, Mauna Loa is in repose and vice versa, suggesting that they may be competing for the same magma supply5,7. Petrological, geochemical and isotope data, however, require a diametrically opposite conclusion. Distinct differences in major-element, trace-element and isotope compositions of lavas are regarded as compelling evidence that the two volcanoes have separate magmatic plumbing systems, supplied by parental magmas from physically and geochemically distinct mantle sources8–13. Here we present preliminary geochemical data which show that in the past 2,000 years Kilauea has erupted a spectrum of lava compositions resembling historical Kilauea lavas at one end and Mauna Loa lavas at the other. We discuss the cause of this diversity, and speculate that magma from Mauna Loa may have invaded Kilauea's 'high-level' magmatic plumbing system.

Published
1989
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25. Geochemical evidence for invasion of Kilauea's plumbing system by Mauna Loa magma

Author

Rhodes, J. M., Wenz, K. P., Neal, C. A., Sparks, J. W., and Lockwood, J. P.

Abstract

From the beginning of the study of Hawaiian volcanism there has been controversy over possible relationships between the neighbouring active volcanoes Mauna Loa and Kilauea1–5. Seismic activity, thought to reflect upward migration of magma, reveals that the magmatic plumbing systems apparently converge at depth to form a broad funnel within the mantle6. Although on rare occasions they have erupted concurrently, the brief historical eruptive record appears to show that when Kilauea is most active, Mauna Loa is in repose and vice versa, suggesting that they may be competing for the same magma supply5,7. Petrological, geochemical and isotope data, however, require a diametrically opposite conclusion. Distinct differences in major-element, trace-element and isotope compositions of lavas are regarded as compelling evidence that the two volcanoes have separate magmatic plumbing systems, supplied by parental magmas from physically and geochemically distinct mantle sources8–13. Here we present preliminary geochemical data which show that in the past 2,000 years Kilauea has erupted a spectrum of lava compositions resembling historical Kilauea lavas at one end and Mauna Loa lavas at the other. We discuss the cause of this diversity, and speculate that magma from Mauna Loa may have invaded Kilauea's 'high-level' magmatic plumbing system.

Published
1989
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