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2,860 results on '"Brown, Craig A."'

1. Hierarchical Multi-Label Classification with Missing Information for Benthic Habitat Imagery

Author

Xu, Isaac, Misiuk, Benjamin, Lowe, Scott C., Gillis, Martin, Brown, Craig J., and Trappenberg, Thomas

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning
Abstract

In this work, we apply state-of-the-art self-supervised learning techniques on a large dataset of seafloor imagery, \textit{BenthicNet}, and study their performance for a complex hierarchical multi-label (HML) classification downstream task. In particular, we demonstrate the capacity to conduct HML training in scenarios where there exist multiple levels of missing annotation information, an important scenario for handling heterogeneous real-world data collected by multiple research groups with differing data collection protocols. We find that, when using smaller one-hot image label datasets typical of local or regional scale benthic science projects, models pre-trained with self-supervision on a larger collection of in-domain benthic data outperform models pre-trained on ImageNet. In the HML setting, we find the model can attain a deeper and more precise classification if it is pre-trained with self-supervision on in-domain data. We hope this work can establish a benchmark for future models in the field of automated underwater image annotation tasks and can guide work in other domains with hierarchical annotations of mixed resolution.

Published
2024
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2. Geometric Tuning of Coordinatively Unsaturated Copper(I) Sites in Metal-Organic Frameworks for Ambient-Temperature Hydrogen Storage.

Author

Yabuuchi, Yuto, Furukawa, Hiroyasu, Carsch, Kurtis, Klein, Ryan, Tkachenko, Nikolay, Huang, Adrian, Cheng, Yongqiang, Taddei, Keith, Novak, Eric, Brown, Craig, Head-Gordon, Martin, and Long, Jeffrey

Abstract

Porous solids can accommodate and release molecular hydrogen readily, making them attractive for minimizing the energy requirements for hydrogen storage relative to physical storage systems. However, H2 adsorption enthalpies in such materials are generally weak (-3 to -7 kJ/mol), lowering capacities at ambient temperature. Metal-organic frameworks with well-defined structures and synthetic modularity could allow for tuning adsorbent-H2 interactions for ambient-temperature storage. Recently, Cu2.2Zn2.8Cl1.8(btdd)3 (H2btdd = bis(1H-1,2,3-triazolo-[4,5-b],[4,5-i])dibenzo[1,4]dioxin; CuI-MFU-4l) was reported to show a large H2 adsorption enthalpy of -32 kJ/mol owing to π-backbonding from CuI to H2, exceeding the optimal binding strength for ambient-temperature storage (-15 to -25 kJ/mol). Toward realizing optimal H2 binding, we sought to modulate the π-backbonding interactions by tuning the pyramidal geometry of the trigonal CuI sites. A series of isostructural frameworks, Cu2.7M2.3X1.3(btdd)3 (M = Mn, Cd; X = Cl, I; CuIM-MFU-4l), was synthesized through postsynthetic modification of the corresponding materials M5X4(btdd)3 (M = Mn, Cd; X = CH3CO2, I). This strategy adjusts the H2 adsorption enthalpy at the CuI sites according to the ionic radius of the central metal ion of the pentanuclear cluster node, leading to -33 kJ/mol for M = ZnII (0.74 Å), -27 kJ/mol for M = MnII (0.83 Å), and -23 kJ/mol for M = CdII (0.95 Å). Thus, CuICd-MFU-4l provides a second, more stable example of optimal H2 binding energy for ambient-temperature storage among reported metal-organic frameworks. Structural, computational, and spectroscopic studies indicate that a larger central metal planarizes trigonal CuI sites, weakening the π-backbonding to H2.

Published
2024

4. Synthesis and characterization of the novel breathing pyrochlore compound Ba3Tm2Zn5O11

Author

Yadav, Lalit, Bag, Rabindranath, Dhakal, Ramesh, Winter, Stephen M., Rau, Jeffrey G., Kolesnikov, Alexander I., Podlesnyak, Andrey A., Brown, Craig M., Butch, Nicholas P., Graf, David, Gingras, Michel J. P., and Haravifard, Sara

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

In this study, a novel material from the rare-earth based breathing pyrochlore family, Ba3Tm2Zn5O11, was successfully synthesized. Powder X-ray diffraction and high-resolution powder neutron diffraction confirmed phase purity and crystal structure, while thermogravimetric analysis revealed incongruent melting behavior compared to its counterpart, Ba3Yb2Zn5O11. High-quality single crystals of Ba3Tm2Zn5O11 were grown using the traveling solvent floating zone technique and assessed using Laue diffractometer and single crystal X-ray diffraction. Thermodynamic characterization indicated paramagnetic behavior down to 0.05 K, and inelastic neutron scattering measurements identified distinct crystal electric field bands. Additional low-energy excitation studies on single crystals revealed dispersionless bands at 0.8 and 1 meV. Computed phonon dispersions from first principles calculations ruled out phonons as the source of these modes, further illustrating the puzzling and unique properties of Ba3Tm2Zn5O11.

Published
2024

5. BenthicNet: A global compilation of seafloor images for deep learning applications

Author

Lowe, Scott C., Misiuk, Benjamin, Xu, Isaac, Abdulazizov, Shakhboz, Baroi, Amit R., Bastos, Alex C., Best, Merlin, Ferrini, Vicki, Friedman, Ariell, Hart, Deborah, Hoegh-Guldberg, Ove, Ierodiaconou, Daniel, Mackin-McLaughlin, Julia, Markey, Kathryn, Menandro, Pedro S., Monk, Jacquomo, Nemani, Shreya, O'Brien, John, Oh, Elizabeth, Reshitnyk, Luba Y., Robert, Katleen, Roelfsema, Chris M., Sameoto, Jessica A., Schimel, Alexandre C. G., Thomson, Jordan A., Wilson, Brittany R., Wong, Melisa C., Brown, Craig J., and Trappenberg, Thomas

Subjects
Computer Science - Computer Vision and Pattern Recognition, Computer Science - Machine Learning
Abstract

Advances in underwater imaging enable the collection of extensive seafloor image datasets that are necessary for monitoring important benthic ecosystems. The ability to collect seafloor imagery has outpaced our capacity to analyze it, hindering expedient mobilization of this crucial environmental information. Recent machine learning approaches provide opportunities to increase the efficiency with which seafloor image datasets are analyzed, yet large and consistent datasets necessary to support development of such approaches are scarce. Here we present BenthicNet: a global compilation of seafloor imagery designed to support the training and evaluation of large-scale image recognition models. An initial set of over 11.4 million images was collected and curated to represent a diversity of seafloor environments using a representative subset of 1.3 million images. These are accompanied by 2.6 million annotations translated to the CATAMI scheme, which span 190,000 of the images. A large deep learning model was trained on this compilation and preliminary results suggest it has utility for automating large and small-scale image analysis tasks. The compilation and model are made openly available for use by the scientific community at https://doi.org/10.20383/103.0614.

Published
2024

7. Nanotechnology solutions for the climate crisis

Author

Campa, Maria Fernanda, Brown, Craig M., Byrley, Peter, Delborne, Jason, Glavin, Nicholas, Green, Craig, Griep, Mark, Kaarsberg, Tina, Linkov, Igor, Miller, Jeffrey B., Porterfield, Joshua E., Schwenzer, Birgit, Spadola, Quinn, Brough, Branden, and Warren, James A.

Published
2024
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9. Breakdown of sound in superfluid helium

Author

Nichitiu, Marc D., Brown, Craig, and Zaliznyak, Igor A.

Subjects
Condensed Matter - Quantum Gases, Condensed Matter - Other Condensed Matter
Abstract

Like elementary particles carry energy and momentum in the Universe, quasiparticles are the elementary carriers of energy and momentum quanta in condensed matter. And, like elementary particles, under certain conditions quasiparticles can be unstable and decay, emitting pairs of less energetic ones. Pitaevskii proposed that such processes exist in superfluid helium, a quantum fluid where the very concept of quasiparticles was borne, and which provided the first spectacular triumph of that concept. Pitaevskii's decays have important consequences, including possible breakdown of a quasiparticle. Here, we present neutron scattering experiments, which provide evidence that such decays explain the collapsing lifetime (strong damping) of higher-energy phonon-roton sound-wave quasiparticles in superfluid helium. This damping develops when helium is pressurized towards crystallization or warmed towards approaching the superfluid transition. Our results resolve a number of puzzles posed by previous experiments and reveal the ubiquity of quasiparticle decays and their importance for understanding quantum matter., Comment: 5 pages, 4 figures main text; 11 supplementary pages with 8 supplementary figures

Published
2023

10. Small-pore hydridic frameworks store densely packed hydrogen

Author

Oh, Hyunchul, Tumanov, Nikolay, Ban, Voraksmy, Li, Xiao, Richter, Bo, Hudson, Matthew R., Brown, Craig M., Iles, Gail N., Wallacher, Dirk, Jorgensen, Scott W., Daemen, Luke, Balderas-Xicohténcatl, Rafael, Cheng, Yongqiang, Ramirez-Cuesta, Anibal J., Heere, Michael, Posada-Pérez, Sergio, Hautier, Geoffroy, Hirscher, Michael, Jensen, Torben R., and Filinchuk, Yaroslav

Published
2024
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12. Quantum disordered ground state in the triangular-lattice magnet NaRuO2

Author

Ortiz, Brenden R, Sarte, Paul M, Avidor, Alon Hendler, Hay, Aurland, Kenney, Eric, Kolesnikov, Alexander I, Pajerowski, Daniel M, Aczel, Adam A, Taddei, Keith M, Brown, Craig M, Wang, Chennan, Graf, Michael J, Seshadri, Ram, Balents, Leon, and Wilson, Stephen D

Published
2023

14. Topical Versus Intravenous Tranexamic Acid in Patients Undergoing Cardiac Surgery: The DEPOSITION Randomized Controlled Trial

Author

Lamy, André, Sirota, Dmitry A., Jacques, Frederic, Poostizadeh, Ahmad, Noiseux, Nicolas, Efremov, Sergey, Demers, Philippe, Akselrod, Boris, Wang, Chew Yin, Arora, Rakesh C., Branny, Piotr, McGuinness, Shay P., Brown, Craig D., Jeanmart, Hugues, Zhao, Qiang, Zhang, Haibo, Belley-Côté, Emilie P., Whitlock, Richard P., Browne, Austin, Copland, Ingrid, Vincent, Jessica, Khatun, Rutaba, Balasubramanian, Kumar, Bangdiwala, Shrikant I., McGillion, Michael H., Fox-Robichaud, Alison E., Spence, Jessica, Yusuf, Salim, and Devereaux, P.J.

Published
2024
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15. Effects of RBT-1 on preconditioning response biomarkers in patients undergoing coronary artery bypass graft or heart valve surgery: a multicentre, double-blind, randomised, placebo-controlled phase 2 trial

Author

Lamy, Andre, Chertow, Glenn, Jessen, Michael, Collar, Alonso, Brown, Craig, Mack, Charles, Marzouk, Mohamed, Scavo, Vincent, Washburn, T Benton, Savage, David, Smith, Julian, Bennetts, Jayme, Assi, Roland, Shults, Christian, Arghami, Arman, Tedesco, Dominic, MacArthur, John, Praetor, Jonathan, Gandhi, Divyakant, Corvera, Joel, Butler, Javed, Devereaux, P.J., Browne, Austin, Wang, Chao, Snapinn, Steve, Zager, Richard, Rodriguez, Jeannette, Ruiz, Stacey, Singh, Bhupinder, Chertow, Glenn M., Brown, Craig D., and Mack, Charles A.

Published
2024
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16. Aluminum formate, Al(HCOO)3: An earth-abundant, scalable, and highly selective material for CO2 capture.

Author

Evans, Hayden, Mullangi, Dinesh, Deng, Zeyu, Wang, Yuxiang, Peh, Shing, Wei, Fengxia, Wang, John, Brown, Craig, Zhao, Dan, Canepa, Pieremanuele, and Cheetham, Anthony

Abstract

A combination of gas adsorption and gas breakthrough measurements show that the metal-organic framework, Al(HCOO)3 (ALF), which can be made inexpensively from commodity chemicals, exhibits excellent CO2 adsorption capacities and outstanding CO2/N2 selectivity that enable it to remove CO2 from dried CO2-containing gas streams at elevated temperatures (323 kelvin). Notably, ALF is scalable, readily pelletized, stable to SO2 and NO, and simple to regenerate. Density functional theory calculations and in situ neutron diffraction studies reveal that the preferential adsorption of CO2 is a size-selective separation that depends on the subtle difference between the kinetic diameters of CO2 and N2. The findings are supported by additional measurements, including Fourier transform infrared spectroscopy, thermogravimetric analysis, and variable temperature powder and single-crystal x-ray diffraction.

Published
2022

19. Efficacy and safety of therapeutic alpha-1-microglobulin RMC-035 in reducing kidney injury after cardiac surgery: a multicentre, randomised, double-blind, parallel group, phase 2a trial

Author

Nazar, Belén Adrio, Böhm, Johannes, Böning, Andreas, Brown, Craig, Burkert, Jan, de Varennes, Benoit, East, Cara, Engelman, Dan, Iglesias, Antonino Ginel, Helms, Sven, Koyner, Jay L., Kress, David, Laflamme, Maxime, Lamy, Andre, Larsson, Tobias E., Matschke, Klaus, Mazer, C David, Albaiceta, Guillermo Muniz, Carvajal, Ignacio Munoz, Myjavec, Andrej, Noiseux, Nicolas, Osaki, Saturo, Reusch, Michael, Copa, Guillermo Reyes, Ronco, Claudio, Scavo, Vincent, Shelstad, Ryan, Swaminathan, Madhav, Szabo, Gabor, Teman, Nicholas, Thielmann, Matthias, Vojacek, Jan, Wahlers, Thorsten, Zarbock, Alexander, and Mazer, C. David

Published
2024
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20. Stacking Faults Assist Lithium-Ion Conduction in a Halide-Based Superionic Conductor

Author

Sebti, Elias, Evans, Hayden A., Chen, Hengning, Richardson, Peter M., White, Kelly M., Giovine, Raynald, Koirala, Krishna Prasad, Xu, Yaobin, Gonzalez-Correa, Eliovardo, Wang, Chongmin, Brown, Craig M., Cheetham, Anthony K., Canepa, Pieremanuele, and Clément, Raphaële J.

Subjects
Condensed Matter - Materials Science
Abstract

In the pursuit of urgently-needed, energy dense solid-state batteries for electric vehicle and portable electronics applications, halide solid electrolytes offer a promising path forward with exceptional compatibility against high-voltage oxide electrodes, tunable ionic conductivities, and facile processing. For this family of compounds, synthesis protocols strongly affect cation site disorder and modulate Li+ mobility. In this work, we reveal the presence of a high concentration of stacking faults in the superionic conductor Li3YCl6 and demonstrate a method of controlling its Li+ conductivity by tuning the defect concentration with synthesis and heat treatments at select temperatures. Leveraging complementary insights from variable temperature synchrotron X-ray diffraction, neutron diffraction, cryogenic transmission electron microscopy, solid-state nuclear magnetic resonance, density functional theory, and electrochemical impedance spectroscopy, we identify the nature of planar defects and the role of nonstoichiometry in lowering Li+ migration barriers and increasing Li site connectivity in mechanochemically-synthesized Li3YCl6. We harness paramagnetic relaxation enhancement to enable 89Y solid-state NMR, and directly contrast the Y cation site disorder resulting from different preparation methods, demonstrating a potent tool for other researchers studying Y-containing compositions. With heat treatments at temperatures as low as 333 K (60{\deg}C), we decrease the concentration of planar defects, demonstrating a simple method for tuning the Li+ conductivity. Findings from this work are expected to be generalizable to other halide solid electrolyte candidates and provide an improved understanding of defect-enabled Li+ conduction in this class of Li-ion conductors.

Published
2022
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22. Albumin Versus Balanced Crystalloid for the Early Resuscitation of Sepsis: An Open Parallel-Group Randomized Feasibility Trial. The ABC-Sepsis Trial

Author

Gray, Alasdair J., Oatey, Katherine, Grahamslaw, Julia, Irvine, Sîan, Cafferkey, John, Kennel, Titouan, Norrie, John, Walsh, Tim, Lone, Nazir, Horner, Daniel, Appelboam, Andy, Hall, Peter, Skipworth, Richard J. E., Bell, Derek, Rooney, Kevin, Shankar-Hari, Manu, Corfield, Alasdair R., Newcombe, Virginia, Chapman, Robert, Hutton, Corinne, Perkins, Gavin, Gordon, Anthony, Keating, Liza, Pallmann, Philip, Armstrong, Ruth, Pollock, Roz, Wackett, Tony, Chapman, Robert, Hutton, Corrine, Kale, Jane, Kale, Neville, Anderson, Rory, Birrell, David, Black, Polly, Blackstock, Caroline, Carter, Jonathan, Clark, Donna, Davidson, Craig, Davie, Carlyn, Rollo, Nicola Di, Ferguson, Andrew, Fethers, Nicholas, Freeman, Nicola, Gibson, Louise, Grant, Alison, Harris, Marie-Clare, James, Ed, Letham, Katy, Lynch, Stephen, McCurrach, Fiona, McKenzie, Suzi, McLaughlin, Connor, Miell, Anna, Moncur, Lyle, O’Brien, Rachel, Pickering, Gillian, Reed, Matt, Rezai, Roozbeh, Robinson, Sara, Skinner, Janet, Walker, Craig, Williams, Alison, Wilson, Emma-Beth, Di Rollo, Nicola, Carruthers, Jennifer, Cheyne, Claire, McGeough, Angela, Lidstone-Scott, Rebecca, Lynch, Stephen, Abel, Lynn, Bongale, Santosh, Currie, Susie, Kane, Donna, Keen, Rachel, Orlikowska, Izabella, Rodden, Natalie, Tait, Jennifer, Thomson, Nicola, Walker, Lauren, Smith, Kate, Brown, Ammani, Cathcart, Susanne, Maguire, Donogh, O’Mailley, Patrick, Rimmer, Dominic, Ward, Catherine, Baxter, Nicola, Denny, Fraser, Doran, Kayleigh, Dunlop, Lisa, Dunn, Jessica, Finnen, Lisa, Green, Darren, Hughes, Emma, Lowe, David, McArthur, Courtney, McLaren, Barbara, McLeish, Kirsty, McMunigal, Linda, McParland, Chris, O’Shaughnessy, Ornagh, Wilson, Mark, Armes, Roland, Brown, Craig, Cooper, Jamie, Connor, David, Collier-Wakefield, Otto, Coutts, Mandi, Cruickshank, Mairi, Ebtehadj, Bianca, Ganley, Pauline, Hiscox, John, Hartman, Catharina, Kane, Leia, Kastora, Stavroula, Lamb, Sarah, McCarthy, Sinead, Mulholland, Conal, Nadim, Imran, Noble, Jennifer, Patton, Gareth, Savage, David, Spowage-Delaney, Benjamin, Doonan, Reece, Lee, Stephanie, Strange, Joshua, Barham, Ffion, Bosanko, Clare, Bullough, Richard, Danglosi, Joan, Freeman, Elaine, Jackson, Luci-Adele, James, Robert, Jose, Louise, Lowe, Fionna, Lowther, Ashleigh, McCarthy, Ian, McConnell, David, Parry, Richard, Shirreff, Henry, Smith, Jason, Squire, Rosalyn, Battishill, Wayne, Boggaram, Girish, Chilcott, Gemma, Gagg, James, Machin, Emma, Shovelton, Charmaine, Purnell, Rebecca, Crosthwaite-Eyre, Richard, Page, George, Pitt, Andrew, Riou, Peter, Sykes, Daisy, Worth, Cassie, Zitter, Lily, Baron, Tanya, Baskaran, Dineshbabu, Beer, Sally, Bhargav, Akshay, Blamey, Helen, Brown, Charlotte, Clare-Gray, Benjamin, Davies, Matthew, Dawson, Neil, Dineen, Karen, Edgar, Iain, Erasu, Vishakha, Faisal, Muhammad, Georgiou, Dominique, Gibson, Alice, Ghataoura, Rashpal, Glover, Samuel, Gordon, Olivia, Ilyas, Sadaf, Jeffs, Aimee, Knott, Henry, Kundoor, Sneha, Martinez, Jose, McCallum, Andrew, Novak, Alex, Panduro, Tine, Pattanshetty, Ravi, Paul, Immanuel, Magallano, Rufino Roger, Razdan, Pamposh, Sambo, Tinelly, Shah, Sumaiyah, Shaikh, Ayisha, Smith, Simon, Thraves, Hannah, Tickle, Charlotte, Ang, Justin, Boyle, Adrian, Hardwick, Susie, Meynell, Kerry, Miller, Samuel, Charsley, Julia, Jolly, Sarah, Mahony, Faye, Moseley-Rodgers, Jade, Sivayoham, Narani, Sheerin, Thomas, Seel, Claire, Abdalla, Mohamed, Cameron, Gregor, Harnett, James, Ramos, Daryl, Perez, Fabiola Sevilla, White, Rachel, Abdullah, Wajiha, Ballard, Suzanna, Barnes, Katie, Clegg, Rebecca, Cousins, Elisha, Cumiskey, Simon, Elwir, Bashar, Ferriman, Alexander, Fletcher, Alison, Griffiths, Charlotte, Guiling, Paolyn, Johnson, Graham, Loach, Benjamin, Matthews, Alison, May-Moulden, Lucy, Norman, Rebecca, Seelly, Helen, Smith, Richard, Tabner, Andrew, Tilbury, Nicholas, Ward, Thomas, Wright, Lianne, Wroblewski, Heather, and Zawadzka, Marcelina

Published
2024
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25. Magnetic properties and signatures of moment ordering in triangular lattice antiferromagnet KCeO$_2$

Author

Bordelon, Mitchell M., Wang, Xiaoling, Pajerowski, Daniel M., Banerjee, Arnab, Sherwin, Mark, Brown, Craig M., Eldeeb, M. S., Petersen, T., Hozoi, L., Rößer, U. K., Mourigal, Martin, and Wilson, Stephen D.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

The magnetic ground state and the crystalline electric field level scheme of the triangular lattice antiferromagnet KCeO$_2$ are investigated. Below $T_N =$ 300 mK, KCeO$_2$ develops signatures of magnetic order in specific heat measurements and low energy inelastic neutron scattering data. Trivalent Ce$^{3+}$ ions in the $D_{3d}$ local environment of this compound exhibit large splittings among the lowest three $4f^1$ Kramers doublets defining for the free ion the $J = 5/2$ sextet and a ground state doublet with dipole character, consistent with recent theoretical predictions in M. S. Eldeeb et al. Phys. Rev. Materials 4, 124001 (2020). An unexplained, additional local mode appears, and potential origins of this anomalous mode are discussed.

Published
2021
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26. Physical properties of a quasi-two-dimensional square lattice antiferromagnet Ba$_2$FeSi$_2$O$_7$

Author

Jang, Tae-Hwan, Do, Seung-Hwan, Lee, Minseong, Zapf, Vivien S., Wu, Hui, Brown, Craig M., Christianson, Andrew D., Cheong, Sang-Wook, and Park, Jae-Hoon

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science
Abstract

We report the magnetization ($\chi$, $M$), specific heat ($C_{\text{P}}$), and neutron powder diffraction results on a quasi-two-dimensional $S$ = 2 square lattice antiferromagnet Ba$_2$FeSi$_2$O$_7$ consisting of FeO$_4$ tetragons with a large compressive distortion (27%). Despite of the quasi-two-dimensional lattice structure, both $\chi$ and $C_{\text{P}}$ present three dimensional magnetic long-range order below the N\'eel temperature $T_{\text{N}}$ = 5.2 K. Neutron diffraction data shows a collinear $Q_{m}$ = (1,0,0.5) antiferromagnetic (AFM) structure with the in-plane ordered magnetic moment suppressed by 26% below $T_{\text{N}}$. Both the AFM structure and the suppressed moments are well explained by the Monte Carlo simulation with a large single-ion ab-plane anisotropy $D$ = 1.4 meV and a rather small in-plane Heisenberg exchange $J_{\text{intra}}$ = 0.15 meV. The characteristic two dimensional spin fluctuations can be recognized in the magnetic entropy release and diffuse scattering above $T_{\text{N}}$. This new quasi-2D magnetic system also displays unusual non-monotonic dependence of the $T_{\text{N}}$ as a function of magnetic field $H$., Comment: 23 pages

Published
2021
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27. Antiferromagnetic Order and Spin-Canting Transition in the Corrugated Square Net Compound Cu$_3$(TeO$_4$)(SO$_4$)$\cdot$H$_2$O

Author

Wang, Zhi-Cheng, Thanabalasingam, Kulatheepan, Scheifers, Jan P., Streeter, Alenna, McCandless, Gregory T., Gaudet, Jonathan, Brown, Craig M., Segre, Carlo U., Chan, k Julia Y., and Tafti, Fazel

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Materials Science, Condensed Matter - Superconductivity
Abstract

Strongly correlated electrons in layered perovskite structures have been the birthplace of high-temperature superconductivity, spin liquid, and quantum criticality. Specifically, the cuprate materials with layered structures made of corner sharing square planar CuO$_4$ units have been intensely studied due to their Mott insulating grounds state which leads to high-temperature superconductivity upon doping. Identifying new compounds with similar lattice and electronic structures has become a challenge in solid state chemistry. Here, we report the hydrothermal crystal growth of a new copper tellurite sulfate Cu$_3$(TeO$_4$)(SO$_4$)$\cdot$H$_2$O, a promising alternative to layered perovskites. The orthorhombic phase (space group $Pnma$) is made of corrugated layers of corner-sharing CuO$_4$ square-planar units that are edge-shared with TeO$_4$ units. The layers are linked by slabs of corner-sharing CuO$_4$ and SO$_4$. Using both the bond valence sum analysis and magnetization data, we find purely Cu$^{2+}$ ions within the layers, but a mixed valence of Cu$^{2+}$/Cu${^+}$ between the layers. Cu$_3$(TeO$_4$)(SO$_4$)$\cdot$H$_2$O undergoes an antiferromagnetic transition at $T_N$=67 K marked by a peak in the magnetic susceptibility. Upon further cooling, a spin-canting transition occurs at $T^{\star}$=12 K evidenced by a kink in the heat capacity. The spin-canting transition is explained based on a $J_1$-$J_2$ model of magnetic interactions, which is consistent with the slightly different in-plane super-exchange paths. We present Cu$_3$(TeO$_4$)(SO$_4$)$\cdot$H$_2$O as a promising platform for the future doping and strain experiments that could tune the Mott insulating ground state into superconducting or spin liquid states., Comment: 29 pages

Published
2021
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28. Early trajectories of virological and immunological biomarkers and clinical outcomes in patients admitted to hospital for COVID-19: an international, prospective cohort study

Author

Sahner, David, Tierney, John, Vogel, Susan E., Herpin, Betsey R., Smolskis, Mary C., McKay, Laura A., Cahill, Kelly, Crew, Page, Sardana, Ratna, Raim, Sharon Segal, Hensely, Lisa, Lorenzo, Johsua, Mock, Rebecca, Zuckerman, Judith, Atri, Negin, Miller, Mark, Vallee, David, Chung, Lucy, Kang, Nayon, Barrett, Kevin, Adam, Stacey J., Read, Sarah, Draghia-Akli, Ruxandra, Currier, Judy, Hughes, Eric, Harrigan, Rachel H., Amos, Laura, Carlsen, Amy, Carter, Anita, Collins, Gary, Davis, Bionca, Denning, Eileen, DuChene, Alain, Eckroth, Kate, Engen, Nicole, Frase, Alex, Gandits, Greg, Grund, Birgit, Harrison, Merrie, Hurlbut, Nancy, Kaiser, Payton, Koopmeiners, Joseph, Larson, Gregg, Meger, Sue, Mistry, Shweta Sharma, Murray, Thomas, Nelson, Ray, Quan, Kien, Quan, Siu Fun, Reilly, Cavan, Siegel, Lianne, Thompson, Greg, Vock, David, Walski, Jamie, Gelijns, Annetine C., Moskowitz, Alan J., Bagiella, Emilia, Moquete, Ellen, O'Sullivan, Karen, Marks, Mary E., Accardi, Evan, Kinzel, Emily, Burris, Sarah, Bedoya, Gabriela, Gupta, Lola, Overbey, Jessica R., Santos, Milerva, Gillinov, Marc A., Miller, Marissa A., Taddei-Peters, Wendy C., Fenton, Kathleen, Sandkovsky, Uriel, Gottlieb, Robert L., Mack, Michael, Berhe, Mezgebe, Haley, Clinton, Dishner, Emma, Bettacchi, Christopher, Golden, Kevin, Duhaime, Erin, Ryan, Madison, Tallmadge, Catherine, Estrada, Lorie, Jones, Felecia, Villa, Samatha, Wang, Samatha, Robert, Raven, Coleman, Tanquinisha, Clariday, Laura, Baker, Rebecca, Hurutado-Rodriguez, Mariana, Iram, Nazia, Fresnedo, Michelle, Davis, Allyson, Leonard, Kiara, Ramierez, Noelia, Thammavong, Jon, Duque, Krizia, Turner, Emma, Fisher, Tammy, Robinson, Dianna, Ransom, Desirae, Maldonado, Nicholas, Lusk, Erica, Killian, Aaron, Palacious, Adriana, Solis, Edilia, Jerrow, Janet, Watts, Matthew, Whitacre, Heather, Cothran, Elizabeth, Smith, Peter K., Barkauskas, Christina E., Vekstein, Andrew M., Ko, Emily R., Dreyer, Grace R., Stafford, Neil, Brooks, Megan, Der, Tatyana, Witte, Marie, Gamarallage, Ruwan, Franzone, John, Ivey, Noel, Lumsden, Rebecca H., Mosaly, Nilima, Mourad, Ahmaad, Holland, Thomas L., Motta, Mary, Lane, Kathleen, McGowan, Lauren M., Stout, Jennifer, Aloor, Heather, Bragg, Kennesha M., Toledo, Barvina, McLendon-Arvik, Beth, Bussadori, Barbara, Hollister, Beth A., Griffin, Michelle, Giangiacomo, Dana M., Rodriguez, Vicente, Bokhart, Gordon, Eichman, Sharon M., Parrino, Patrick E., Spindel, Stephen, Bansal, Aditya, Baumgarten, Katherine, Hand, Johnathan, Vonderhaar, Derek, Nossaman, Bobby, Sylvia Laudun, Ames, DeAnna, Broussard, Shane, Hernandez, Nilmo, Isaac, Geralyn, Dinh, Huan, Zheng, Yiling, Tran, Sonny, McDaniel, Hunter, Crovetto, Nicolle, Perin, Emerson, Costello, Briana, Manian, Prasad, Sohail, M. Rizwan, Postalian, Alexander, Hinsu, Punit, Watson, Carolyn, Chen, James, Fink, Melyssa, Sturgis, Lydia, Walker, Kim, Mahon, Kim, Parenti, Jennifer, Kappenman, Casey, Knight, Aryn, Sturek, Jeffrey M., Barros, Andrew, Enfield, Kyle B., Kadl, Alexandra, Green, China J., Simon, Rachel M., Fox, Ashley, Thornton, Kara, Adams, Amy, Badhwar, Vinay, Sharma, Sunil, Peppers, Briana, McCarthy, Paul, Krupica, Troy, Sarwari, Arif, Reece, Rebecca, Fornaresico, Lisa, Glaze, Chad, Evans, Raquel, Di, Fang, Carlson, Shawn, Aucremanne, Tanja, Tennant, Connie, Sutton, Lisa Giblin, Buterbaugh, Sabrina, Williams, Roger, Bunner, Robin, Traverse, Jay H., Rhame, Frank, Huelster, Joshua, Kethireddy, Rajesh, Davies, Irena, Salamanca, Julianne, Majeski, Christine, Skelton, Paige, Zarambo, Maria, Sarafolean, Andrea, Bowdish, Michael E., Borok, Zea, Wald-Dickler, Noah, Hutcheon, Douglass, Towfighi, Amytis, Lee, Mary, Lewis, Meghan R., Spellberg, Brad, Sher, Linda, Sharma, Aniket, Olds, Anna P., Justino, Chris, Loxano, Edward, Romero, Chris, Leong, Janet, Rodina, Valentina, Quesada, Christine, Hamilton, Luke, Escobar, Jose, Leshnower, Brad, Bender, William, Sharifpour, Milad, Miller, Jeffrey, Farrington, Woodrow, Baio, Kim T., McBride, Mary, Fielding, Michele, Mathewson, Sonya, Porte, Kristina, Maton, Missy, Ponder, Chari, Haley, Elisabeth, Spainhour, Christine, Rogers, Susan, Tyler, Derrick, Madathil, Ronson J., Rabin, Joseph, Levine, Andrea, Saharia, Kapil, Tabatabai, Ali, Lau, Christine, Gammie, James S., Peguero, Maya-Loren, McKernan, Kimberly, Audette, Mathew, Fleischmann, Emily, Akbari, Kreshta, Lee, Myounghee, Chi, Andrew, Salehi, Hanna, Pariser, Alan, Nyguyen, Phuong Tran, Moore, Jessica, Gee, Adrienne, Vincent, Shelika, Zuckerman, Richard A., Iribarne, Alexander, Metzler, Sara, Shipman, Samantha, Johnson, Haley, Newton, Crystallee, Parr, Doug, Miller, Leslie, Schelle, Beth, McLean, Sherry, Rothbaum, Howard R., Alvarez, Michael S., Kalan, Shivam P., Germann, Heather H., Hendershot, Jennifer, Moroney, Karen, Herring, Karen, Cook, Sharri, Paul, Pam, Walker-Ignasiak, Rebecca, North, Crystal, Oldmixon, Cathryn, Ringwood, Nancy, Muzikansky, Ariela, Morse, Richard, Fitzgerald, Laura, Morin, Haley D., Brower, Roy G., Reineck, Lora A., Bienstock, Karen, Steingrub, Jay H., Hou, Peter K., Steingrub, Jay S., Tidswell, Mark A., Kozikowski, Lori-Ann, Kardos, Cynthia, DeSouza, Leslie, Romain, Sarah, Thornton-Thompson, Sherell, Talmor, Daniel, Shapiro, Nathan, Andromidas, Konstantinos, Banner-Goodspeed, Valerie, Bolstad, Michael, Boyle, Katherine L., Cabrera, Payton, deVilla, Arnaldo, Ellis, Joshua C., Grafals, Ana, Hayes, Sharon, Higgins, Conor, Kurt, Lisa, Kurtzman, Nicholas, Redman, Kimberly, Rosseto, Elinita, Scaffidi, Douglas, Filbin, Michael R., Hibbert, Kathryn A., Parry, Blair, Margolin, Justin, Hillis, Brooklynn, Hamer, Rhonda, Brait, Kelsey, Beakes, Caroline, McKaig, Brenna, Kugener, Eleonore, Jones, Alan E., Galbraith, James, Nandi, Utsav, Peacock, Rebekah, Hendey, Gregory, Kangelaris, Kirsten, Ashktorab, Kimia, Gropper, Rachel, Agrawal, Anika, Yee, Kimberley J., Jauregui, Alejandra E., Zhuo, Hanjing, Almasri, Eyad, Fayed, Mohamed, Hubel, Kinsley A., Hughes, Alyssa R., Garcia, Rebekah L., Lim, George W., Chang, Steven Y., Lin, Michael Y., Vargas, Julia, Sihota, Hena, Beutler, Rebecca, Agarwal, Trisha, Wilson, Jennifer G., Vojnik, Rosemary, Perez, Cynthia, McDowell, Jordan H., Roque, Jonasel, Wang, Henry, Huebinger, Ryan M., Patel, Bela, Vidales, Elizabeth, Albertson, Timothy, Hardy, Erin, Harper, Richart, Moss, Marc A., Baduashvili, Amiran, Chauhan, Lakshmi, Douin, David J., Martinez, Flora, Finck, Lani L., Bastman, Jill, Howell, Michelle, Higgins, Carrie, McKeehan, Jeffrey, Finigan, Jay, Stubenrauch, Peter, Janssen, William J., Griesmer, Christine, VerBurg, Olivia, Hyzy, Robert C., Park, Pauline K., Nelson, Kristine, McSparron, Jake I., Co, Ivan N., Wang, Bonnie R., Jimenez, Jose, Olbrich, Norman, McDonough, Kelli, Jia, Shijing, Hanna, Sinan, Gong, Michelle N., Richardson, Lynne D., Nair, Rahul, Lopez, Brenda, Amosu, Omowunmi, Offor, Obiageli, Tzehaie, Hiwet, Nkemdirim, William, Boujid, Sabah, Mosier, Jarrod M., Hypes, Cameron, Campbell, Elizabeth Salvagio, Bixby, Billie, Gilson, Boris, Lopez, Anitza, Bime, Christian, Parthasarathy, Sairam, Cano, Ariana M., Hite, R. Duncan, Terndrup, Thomas E., Wiedemann, Herbert P., Hudock, Kristin, Tanzeem, Hammad, More, Harshada, Martinkovic, Jamie, Sellers, Susan, Houston, Judy, Burns, Mary, Kiran, Simra, Roads, Tammy, Kennedy, Sarah, Duggal, Abhijit, Thiruchelvam, Nirosshan, Ashok, Kiran, King, Alexander H., Mehkri, Omar, Dugar, Siddharth, Sahoo, Debasis, Yealy, Donald M., Angus, Derek C., Weissman, Alexandra J., Vita, Tina M., Berryman, Emily, Hough, Catherine L., Khan, Akram, Krol, Olivia F., Mills, Emmanuel, Kinjal, Mistry, Briceno, Genesis, Reddy, Raju, Hubel, Kinsley, Jouzestani, Milad K., McDougal, Madeline, Deshmukh, Rupali, Johnston, Nicholas J., Robinson, Bryce H., Gundel, Staphanie J., Katsandres, Sarah C., Chen, Peter, Torbati, Sam S., Parimon, Tanyalak, Caudill, Antonina, Mattison, Brittany, Jackman, Susan E., Chen, Po-En, Bayoumi, Emad, Ojukwu, Cristabelle, Fine, Devin, Weissberg, Gwendolyn, Isip, Katherine, Choi-Kuaea, Yunhee, Mehdikhani, Shaunt, Dar, Tahir B., Fleury Augustin, Nsole Biteghe, Tran, Dana, Dukov, Jennifer Emilow, Matusov, Yuri, Choe, June, Hindoyan, Niree A., Wynter, Timothy, Pascual, Ethan, Clapham, Gregg J., Herrera, Lisa, Caudill, Antonia, O’Mahony, D. Shane, Nyatsatsang, Sonam T., Wilson, David M., Wallick, Julie A., Duven, Alexandria M., Fletcher, Dakota D., Miller, Chadwick, Files, D. Clark, Gibbs, Kevin W., Flores, Lori S., LaRose, Mary E., Landreth, Leigha D., Palacios, D. Rafael, Parks, Lisa, Hicks, Madeline, Goodwin, Andrew J., Kilb, Edward F., Lematty, Caitlan T., Patti, Kerilyn, Grady, Abigail, Rasberry, April, Morris, Peter E., Sturgill, Jamie L., Cassity, Evan P., Dhar, Sanjay, Montgomery-Yates, Ashley A., Pasha, Sarah N., Mayer, Kirby P., Pharm.D., Brittany Bissel, Trott, Terren, Rehman, Shahnaz, de Wit, Marjolein, Mason, Jessica, Bledsoe, Joseph, Knowlton, Kirk U., Brown, Samuel, Lanspa, Michael, Leither, Lindsey, Pelton, Ithan, Armbruster, Brent P., Montgomery, Quinn, Kumar, Naresh, Fergus, Melissa, Imel, Karah, Palmer, Ghazal, Webb, Brandon, Klippel, Carolyn, Jensen, Hannah, Duckworth, Sarah, Gray, Andrew, Burke, Tyler, Knox, Dan, Lumpkin, Jenna, Aston, Valerie T., Applegate, Darrin, Serezlic, Erna, Brown, Katie, Merril, Mardee, Harris, Estelle S., Middleton, Elizabeth A., Barrios, Macy A.G., Greer, Jorden, Schmidt, Amber D., Webb, Melissa K., Paine, Roert, Callahan, Sean J., Waddoups, Lindsey J., Yamane, Misty B., Self, Wesley H., Rice, Todd W., Casey, Jonathan D., Johnson, Jakea, Gray, Christopher, Hays, Margaret, Roth, Megan, Menon, Vidya, Kasubhai, Moiz, Pillai, Anjana, Daniel, Jean, Sittler, Daniel, Kanna, Balavenkatesh, Jilani, Nargis, Amaro, Francisco, Santana, Jessica, Lyakovestsky, Aleksandr, Madhoun, Issa, Desroches, Louis Marie, Amadon, Nicole, Bahr, Alaa, Ezzat, Imaan, Guerrero, Maryanne, Padilla, Joane, Fullmer, Jessie, Singh, Inderpreet, Ali Shah, Syed Hamad, Narang, Rajeev, Mock, Polly, Shadle, Melissa, Hernandez, Brenda, Welch, Kevin, Payne, Andrea, Ertl, Gabriela, Canario, Daniel, Barrientos, Isabel, Goss, Danielle, DeVries, Mattie, Folowosele, Ibidolapo, Garner, Dorothy, Gomez, Mariana, Price, Justin, Bansal, Ekta, Wong, Jim, Faulhaber, Jason, Fazili, Tasaduq, Yeary, Brian, Ndolo, Ruth, Bryant, Christina, Smigeil, Bridgette, Robinson, Philip, Najjar, Rana, Jones, Patrice, Nguyen, Julie, Chin, Christina, Taha, Hassan, Najm, Salah, Smith, Christopher, Moore, Jason, Nassar, Talal, Gallinger, Nick, Christian, Amy, Mauer, D’Amber, Phipps, Ashley, Waters, Michael, Zepeda, Karla, Coslet, Jordan, Landazuri, Rosalynn, Pineda, Jacob, Uribe, Nicole, Garcia, Jose Ruiz, Barbabosa, Cecilia, Sandler, Kaitlyn, Overcash, J. Scott, Marquez, Adrienna, Chu, Hanh, Lee, Kia, Quillin, Kimberly, Garcia, Andrea, Lew, Pauline, Rogers, Ralph, Shehadeh, Fadi, Mylona, Evangelia K., Kaczynski, Matthew, Tran, Quynh-Lam, Benitez, Gregorio, Mishra, Biswajit, Felix, Lewis Oscar, Vafea, Maria Tsikala, Atalla, Eleftheria, Davies, Robin, Hedili, Salma, Monkeberg, Maria Andrea, Tabler, Sandra, Harrington, Britt, Meegada, Sreenath, Koripalli, Venkata Sandeep, Muddana, Prithvi, Jain, Lakshay, Undavalli, Chaitanya, Kavya, Parasa, Ibiwoye, Mofoluwaso, Akilo, Hameed, Lovette, Bryce D., Wylie, Jamie-Crystal, Smith, Diana M., Poon, Kenneth, Eckardt, Paula, Heysu, Rubio-Gomez, Sundararaman, Nithya, Alaby, Doris, Sareli, Candice, Sánchez, Adriana, Popielski, Laura, Kambo, Amy, Viens, Kimberley, Turner, Melissa, Vjecha, Michael J., Weintrob, Amy, Brar, Indira, Markowitz, Norman, Pastor, Erika, Corpuz, Roweena, Alangaden, George, McKinnon, John, Ramesh, Mayur, Herc, Erica, Yared, Nicholas, Lanfranco, Odaliz Abreu, Rivers, Emanuel, Swiderek, Jennifer, Gupta, Ariella Hodari, Pabla, Pardeep, Eliya, Sonia, Jazrawi, Jehan, Delor, Jeremy, Desai, Mona, Cook, Aaron, Jaehne, Anja Kathrina, Gill, Jasreen Kaur, Renaud, Sheri, Sarveswaran, Siva, Gardner, Edward, Scott, James, Bianchini, Monica, Melvin, Casey, Kim, Gina, Wyles, David, Kamis, Kevin, Miller, Rachel, Douglas, Ivor, Haukoos, Jason, Hicks, Carrie, Lazarte, Susana, Marines-Price, Rubria, Osuji, Alice, Agbor Agbor, Barbine Tchamba, Petersen, Tianna, Kamel, Dena, Hansen, Laura, Garcia, Angie, Cha, Christine, Mozaffari, Azadeh, Hernandez, Rosa, Cutrell, James, Kim, Mina, DellaValle, Natalie, Gonzales, Sonia, Somboonwit, Charurut, Oxner, Asa, Guerra, Lucy, Hayes, Michael, Nguyen, Thi, Tran, Thanh, Pinto, Avenette, Hatlen, Timothy, Anderson, Betty, Zepeda-Gutierrez, Ana, Martin, Dannae, Temblador, Cindi, Cuenca, Avon, Tanoviceanu, Roxanne, Prieto, Martha, Guerrero, Mario, Daar, Eric, Correa, Ramiro, Hartnell, Gabe, Wortmann, Glenn, Doshi, Saumil, Moriarty, Theresa, Gonzales, Melissa, Garman, Kristin, Baker, Jason V., Frosch, Anne, Goldsmith, Rachael, Driver, Brian, Frank, Christine, Leviton, Tzivia, Prekker, Matthew, Jibrell, Hodan, Lo, Melanie, Klaphake, Jonathan, Mackedanz, Shari, Ngo, Linh, Garcia-Myers, Kelly, Kunisaki, Ken M., Wendt, Chris, Melzer, Anne, Wetherbee, Erin, Drekonja, Dimitri, Pragman, Alexa, Hamel, Aimee, Thielen, Abbie, Hassler, Miranda, Walquist, Mary, Augenbraun, Michael, George, Jensen, Demeo, Lynette, Mishko, Motria, Thomas, Lorraine, Tatem, Luis, Dehovitz, Jack, Abassi, Mahsa, Leuck, Anne-Marie, Rao, Via, Pullen, Matthew, Luke, Darlette, LaBar, Derek, Christiansen, Theresa, Howard, Diondra, Biswas, Kousick, Harrington, Cristin, Garcia, Amanda, Bremer, Tammy, Burke, Tara, Koker, Brittany, Davis-Karim, Anne, Pittman, David, Vasudeva, Shikha S., Johnstone, Jaylynn R., Agnetti, Kate, Davis, Ruby, Trautner, Barbara, Hines-Munson, Casey, Van, John, Dillon, Laura, Wang, Yiqun, Nagy-Agren, Stephanie, Vasudeva, Shikha, Ochalek, Tracy, Caldwell, Erin, Humerickhouse, Edward, Boone, David, McGraw, William, Looney, David J., Mehta, Sanjay R., Johns, Scott Thompson, St. John, Melissa, Raceles, Jacqueline, Sear, Emily, Funk, Stephen, Cesarini, Rosa, Fang, Michelle, Nicalo, Keith, Drake, Wonder, Jones, Beatrice, Holtman, Teresa, Nguyen, Hien H., Maniar, Archana, Johnson, Eric A., Nguyen, Lam, Tran, Michelle T., Barrett, Thomas W., Johnston, Tera, Huggins, John T., Beiko, Tatsiana Y., Hughes, Heather Y., McManigle, William C., Tanner, Nichole T., Washburn, Ronald G., Ardelt, Magdalena, Tuohy, Patricia A., Mixson, Jennifer L., Hinton, Charles G., Thornley, Nicola, Allen, Heather, Elam, Shannon, Boatman, Barry, Baber, Brittany J., Ryant, Rudell, Roller, Brentin, Nguyen, Chinh, Mikail, Amani Morgan, Research, Marivic Hansen, Lichtenberger, Paola, Baracco, Gio, Ramos, Carol, Bjork, Lauren, Sueiro, Melyssa, Tien, Phyllis, Freasier, Heather, Buck, Theresa, Nekach, Hafida, Holodniy, Mark, Chary, Aarthi, Lu, Kan, Peters, Theresa, Lopez, Jessica, Tan, Susanna Yu, Lee, Robert H., Asghar, Aliya, Karyn Isip, Tasadduq Karim, Le, Katherine, Nguyen, Thao, Wong, Shinn, Raben, Dorthe, Murray, Daniel D., Jensen, Tomas O., Peters, Lars, Aagaard, Bitten, Nielsen, Charlotte B., Krapp, Katharina, Nykjær, Bente Rosdahl, Olsson, Christina, Kanne, Katja Lisa, Grevsen, Anne Louise, Joensen, Zillah Maria, Bruun, Tina, Bojesen, Ane, Woldbye, Frederik, Normand, Nick E., Esman, Frederik V.L., Benfield, Thomas, Clausen, Clara Lundetoft, Hovmand, Nichlas, Israelsen, Simone Bastrup, Iversen, Katrine, Leding, Caecilie, Pedersen, Karen Brorup, Thorlacius-Ussing, Louise, Tinggaard, Michaela, Tingsgard, Sandra, Krohn-Dehli, Louise, Pedersen, Dorthe, Villadsen, Signe, Staehr Jensen, Jens-Ulrik, Overgaard, Rikke, Rastoder, Ema, Heerfordt, Christian, Hedsund, Caroline, Ronn, Christian Phillip, Kamstrup, Peter Thobias, Hogsberg, Dorthe Sandbaek, Bergsoe, Christina, Søborg, Christian, Hissabu, Nuria M.S., Arp, Bodil C., Ostergaard, Lars, Staerke, Nina Breinholt, Yehdego, Yordanos, Sondergaard, Ane, Johansen, Isik S., Pedersen, Andreas Arnholdt, Knudtzen, Fredrikke C., Larsen, Lykke, Hertz, Mathias A., Fabricius, Thilde, Holden, Inge K., Lindvig, Susan O., Helleberg, Marie, Gerstoft, Jan, Kirk, Ole, Jensen, Tomas Ostergaard, Madsen, Birgitte Lindegaard, Pedersen, Thomas Ingemann, Harboe, Zitta Barrella, Roge, Birgit Thorup, Hansen, Thomas Michael, Glesner, Matilde Kanstrup, Lofberg, Sandra Valborg, Nielsen, Ariella Denize, Leicht von Huth, Sebastian, Nielsen, Henrik, Thisted, Rikke Krog, Petersen, Kristine Toft, Juhl, Maria Ruwald, Podlekareva, Daria, Johnsen, Stine, Andreassen, Helle Frost, Pedersen, Lars, Clara Ellinor Lindnér, Cecilia Ebba, Wiese, Lothar, Knudsen, Lene Surland, Skrøder Nytofte, Nikolaj Julian, Havmøller, Signe Ravn, Expósito, Maria, Badillo, José, Martínez, Ana, Abad, Elena, Chamorro, Ana, Figuerola, Ariadna, Mateu, Lourdes, España, Sergio, Lucero, Maria Constanza, Santos, José Ramón, Lladós, Gemma, Lopez, Cristina, Carabias, Lydia, Molina-Morant, Daniel, Loste, Cora, Bracke, Carmen, Siles, Adrian, Fernández-Cruz, Eduardo, Di Natale, Marisa, Padure, Sergiu, Gomez, Jimena, Ausin, Cristina, Cervilla, Eva, Balastegui, Héctor, Sainz, Carmen Rodríguez, Lopez, Paco, Carbone, Javier, Escobar, Mariam, Balerdi, Leire, Legarda, Almudena, Roldan, Montserrat, Letona, Laura, Muñoz, José, Camprubí, Daniel, Arribas, Jose R., Sánchez, Rocio Montejano, Díaz-Pollán, Beatriz, Stewart, Stefan Mark, Garcia, Irene, Borobia, Alberto, Mora-Rillo, Marta, Estrada, Vicente, Cabello, Noemi, Nuñez-Orantos, M.J., Sagastagoitia, I., Homen, J.R., Orviz, E., Montalvá, Adrián Sánchez, Espinosa-Pereiro, Juan, Bosch-Nicolau, Pau, Salvador, Fernando, Burgos, Joaquin, Morales-Rull, Jose Luis, Moreno Pena, Anna Maria, Acosta, Cristina, Solé-Felip, Cristina, Horcajada, Juan P., Sendra, Elena, Castañeda, Silvia, López-Montesinos, Inmaculada, Gómez-Junyent, Joan, Gonzáles, Carlota Gudiol, Cuervo, Guilermo, Pujol, Miquel, Carratalà, Jordi, Videla, Sebastià, Günthard, Huldrych, Braun, Dominique L., West, Emily, M’Rabeth-Bensalah, Khadija, Eichinger, Mareile L., Grüttner-Durmaz, Manuela, Grube, Christina, Zink, Veronika, pharmacist, Goes pharmacist, Josefine, Fätkenheuer, Gerd, Malin, Jakob J., Tsertsvadze, Tengiz, Abutidze, Akaki, Chkhartishvili, Nikoloz, Metchurtchlishvili, Revaz, Endeladze, Marina, Paciorek, Marcin, Bursa, Dominik, Krogulec, Dominika, Pulik, Piotr, Ignatowska, Anna, Horban, Andrzej, Bakowska, Elzbieta, Kowaska, Justyna, Bednarska, Agnieszka, Jurek, Natalia, Skrzat-Klapaczynska, Agata, Bienkowski, Carlo, Hackiewicz, Malgorzata, Makowiecki, Michal, Platowski, Antoni, Fishchuk, Roman, Kobrynska, Olena, Levandovska, Khrystyna, Kirieieva, Ivanna, Kuziuk, Mykhailo, Naucler, Pontus, Perlhamre, Emma, Mazouch, Lotta, Kelleher, Anthony, Polizzotto, Mark, Carey, Catherine, Chang, Christina C., Hough, Sally, Virachit, Sophie, Davidson, Sarah, Bice, Daniel J., Ognenovska, Katherine, Cabrera, Gesalit, Flynn, Ruth, Young, Barnaby E., Chia, Po Ying, Lee, Tau Hong, Lin, Ray J., Lye, David C., Ong, Sean W.X., Puah, Ser Hon, Yeo, Tsin Wen, Diong, Shiau Hui, Ongko, Juwinda, Yeo, He Ping, Eriobu, Nnakelu, Kwaghe, Vivian, Zaiyad, Habib, Idoko, Godwin, Uche, Blessing, Selvamuthu, Poongulali, Kumarasamy, Nagalingeswaran, Beulah, Faith Ester, Govindarajan, Narayan, Mariyappan, Kowsalya, Losso, Marcelo H., Abela, Cecilia, Moretto, Renzo, Belloc, Carlos G., Ludueña, Jael, Amar, Josefina, Toibaro, Javier, Macias, Laura Moreno, Fernandez, Lucia, Frare, Pablo S., Chaio, Sebastian R., Pachioli, Valeria, Timpano, Stella M., Sanchez, Marisa del Lujan, de Paz Sierra, Mariana, Stanek, Vanina, Belloso, Waldo, Cilenti, Flavia L., Valentini, Ricardo N., Stryjewski, Martin E., Locatelli, Nicolas, Soler Riera, Maria C., Salgado, Clara, Baeck, Ines M., Di Castelnuovo, Valentina, Zarza, Stella M., Hudson, Fleur, Parmar, Mahesh K.B., Goodman, Anna L., Dphil, Badrock, Jonathan, Gregory, Adam, Goodall, Katharine, Harris, Nicola, Wyncoll, James, Bhagani, S., Rodger, A., Luntiel, A., Patterson, C., Morales, J., Witele, E., Preston, A.-M., Nandani, A., Price, D.A., Hanrath, Aiden, Nell, Jeremy, Patel, Bijal, Hays, Carole, Jones, Geraldine, Davidson, Jade, Bawa, T., Mathews, M., Mazzella, A., Bisnauthsing, K., Aguilar-Jimenez, L., Borchini, F., Hammett, S., Touloumi, Giota, Pantazis, Nikos, Gioukari, Vicky, Souliou, Tania, Antoniadou, A., Protopapas, K., Kavatha, D., Grigoropoulou, S., Oikonomopoulo, C., Moschopoulos, C., Koulouris, N.G., Tzimopoulos, K., Koromilias, A., Argyraki, K., Lourida, P., Bakakos, P., Kalomenidis, I., Vlachakos, V., Barmparessou, Z., Balis, E., Zakynthinos, S., Sigala, I., Gianniou, N., Dima, E., Magkouta, S., Synolaki, E., Konstanta, S., Vlachou, M., Stathopoulou, P., Panagopoulos, P., Petrakis, V., Papazoglou, D., Tompaidou, E., Isaakidou, E., Poulakou, G., Rapti, V., Leontis, K., Nitsotolis, T., Athanasiou, K., Syrigos, K., Kyriakoulis, K., Trontzas, I., Arfara-Melanini, M., Kolonis, V., Kityo, Cissy, Mugerwa, Henry, Kiweewa, Francis, Kimuli, Ivan, Lukaakome, Joseph, Nsereko, Christoher, Lubega, Gloria, Kibirige, Moses, Nakahima, William, Wangi, Deus, Aguti, Evelyne, Generous, Lilian, Massa, Rosemary, Nalaki, Margaret, Magala, Felix, Nabaggala, Phiona Kaweesi, Kidega, Robert, Faith, Oryem Daizy, Florence, Apio, Emmanuel, Ocung, Beacham, Mugoonyi Paul, Geoffrey, Amone, Nakiboneka, Dridah, Apiyo, Paska, Kirenga, Bruce, Atukunda, Angella, Muttamba, Winters, Remmy, Kyeyume, Segawa, Ivan, Pheona, Nsubuga, Kigere, David, Mbabazi, Queen Lailah, Boersalino, Ledra, Nyakoolo, Grace, Fred, Aniongo, Alupo, Alice, Ebong, Doryn, Monday, Edson, Nalubwama, Ritah Norah, Kainja, Milton, Ambrose, Munu, Kwehayo, Vanon, Nalubega, Mary Grace, Ongoli, Augustine, Obbo, Stephen, Sebudde, Nicholus, Alaba, Jeniffer, Magombe, Geoffrey, Tino, Harriet, Obonya, Emmanuel, Lutaakome, Joseph, Kitonsa, Jonathan, Onyango, Martin, Naboth, Tukamwesiga, Naluyinda, Hadijah, Nanyunja, Regina, Irene, Muttiibwa, Jane, Biira, Wimfred, Kyobejja, Leonard, Ssemazzi, Deus, Tkiinomuhisha, Babra, Namasaba, Taire, Paul, Nabankema, Evelyn, Ogavu, Joseph, Mugerwa, Oscar, Okoth, Ivan, Mwebaze, Raymond, Mugabi, Timothy, Makhoba, Anthony, Arikiriza, Phiona, Theresa, Nabuuma, Nakayima, Hope, Frank, Kisuule, Ramgi, Patrícia, Pereira, Kássia, Osinusi, Anu, Cao, Huyen, Klekotka, Paul, Price, Karen, Nirula, Ajay, Osei, Suzette, Tipple, Craig, Wills, Angela, Peppercorn, Amanda, Watson, Helen, Gupta, Rajesh, Alexander, Elizabeth, Mogalian, Erik, Lin, Leo, Ding, Xiao, Margolis, David, Yan, Li, Girardet, Jean-Luc, Ma, Ji, Hong, Zhi, Zhu, Quing, Seegobin, Seth, Gibbs, Michael, Latchman, Mickel, Hasior, Katarzyna, Bouquet, Jerome, Wei, Jianxin, Streicher, Katie, Schmelzer, Albert, Brooks, Dennis, Butcher, Jonny, Tonev, Dimitar, Arbetter, Douglas, Damstetter, Philippe, Legenne, Philippe, Stumpp, Michael, Goncalves, Susana, Ramanathan, Krishnan, Chandra, Richa, Baseler, Beth, Teitelbaum, Marc, Schechner, Adam, Holley, H. Preston, Jankelevich, Shirley, Becker, Nancy, Dolney, Suzanne, Hissey, Debbie, Simpson, Shelly, Kim, Mi Ha, Beeler, Joy, Harmon, Liam, Asomah, Mabel, Jato, Yvonne, Stottlemyer, April, Tang, Olivia, Vanderpuye, Sharon, Yeon, Lindsey, Buehn, Molly, Eccard-Koons, Vanessa, Frary, Sadie, MacDonald, Leah, Cash, Jennifer, Hoopengardner, Lisa, Linton, Jessica, Schaffhauser, Marylu, Nelson, Michaela, Spinelli-Nadzam, Mary, Proffitt, Calvin, Lee, Christopher, Engel, Theresa, Fontaine, Laura, Osborne, C.K., Hohn, Matt, Galcik, Michael, Thompson, DeeDee, Kopka, Stacey, Shelley, Denise M., Mendez, Gregg, Brown, Shawn, Albert, Sara, Balde, Abby, Baracz, Michelle, Bielica, Mona, Billouin-Frazier, Shere, Choudary, Jay, Dixon, Mary, Eyler, Carolyn, Frye, Leanne, Gertz, Jensen, Giebeig, Lisa, Gulati, Neelam, Hankinson, Liz, Hogarty, Debi, Huber, Lynda, Krauss, Gary, Lake, Eileen, Manandhar, Meryan, Rudzinski, Erin, Sandrus, Jen, Suders, Connie, Natarajan, Ven, Rupert, Adam W., Baseler, Michael, Lynam, Danielle, Imamichi, Tom, Laverdure, Sylvain, McCormack, Ashley, Paudel, Sharada, Cook, Kyndal, Haupt, Kendra, Khan, Ayub, Hazen, Allison, Badralmaa, Yunden, Smith, Kenneth, Patel, Bhakti, Kubernac, Amanda, Kubernac, Robert, Hoover, Marie L., Solomon, Courtney, Rashid, Marium, Murphy, Joseph, Brown, Craig, DuChateau, Nadine, Ellis, Sadie, Flosi, Adam, Fox, Lisa, Johnson, Les, Nelson, Rich, Stojanovic, Jelena, Treagus, Amy, Wenner, Christine, Williams, Richard, Jensen, Tomas O, Murray, Thomas A, Grandits, Greg A, Jain, Mamta K, Shaw-Saliba, Kathryn, Matthay, Michael A, Baker, Jason V, Dewar, Robin L, Goodman, Anna L, Hatlen, Timothy J, Highbarger, Helene C, Lallemand, Perrine, Leshnower, Bradley G, Looney, David, Moschopoulos, Charalampos D, Murray, Daniel D, Mylonakis, Eleftherios, Rehman, M Tauseef, Rupert, Adam, Stevens, Randy, Turville, Stuart, Wick, Katherine, Lundgren, Jens, and Ko, Emily R

Published
2024
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33. Chemical Bonding Governs Complex Magnetism in MnPt5P

Author

Gui, Xin, Klein, Ryan A., Brown, Craig M., and Xie, Weiwei

Subjects
Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons
Abstract

Subtle changes in chemical bonds may result in dramatic revolutions in magnetic properties in solid state materials. MnPt5P, a new derivative of the rare-earth-free ferromagnetic MnPt5As, was discovered and is presented in this work. MnPt5P was synthesized and its crystal structure and chemical composition were characterized by X-ray diffraction as well as energy-dispersive X-ray spectroscopy. Accordingly, MnPt5P crystallizes in the layered tetragonal structure with the space group P4/mmm (No. 123), in which the face-shared Mn@Pt12 polyhedral layers are separated by P layers. In contrast to the ferromagnetism observed in MnPt5As, the magnetic properties measurements on MnPt5P show antiferromagnetic ordering occurs at ~188 K with a strong magnetic anisotropy in and out of the ab-plane. Moreover, a spin-flop transition appears when a high magnetic field is applied. An A-type antiferromagnetic structure was obtained from the analysis of powder neutron diffraction (PND) patterns collected at 150 K and 9 K. Calculated electronic structures imply that hybridization of Mn-3d and Pt-5d orbitals are critical for both the structural stability and observed magnetic properties. Semi-empirical molecular orbitals calculations on both MnPt5P and MnPt5As indicate that the lack of 4p character on the P atoms at the highest occupied molecular orbital (HOMO) in MnPt5P may cause the different magnetic behavior in MnPt5P compared to MnPt5As. The discovery of MnPt5P, along with our previously reported MnPt5As, parametrizes the end points of a tunable system to study the chemical bonding which tunes the magnetic ordering from ferromagnetism to antiferromagnetism with strong spin-orbit coupling (SOC) effect.

Published
2020

34. Competing Antiferromagnetic-Ferromagnetic States in $\it{d^7}$ Kitaev Honeycomb Magnet

Author

Vivanco, Hector K., Trump, Benjamin A., Brown, Craig M., and McQueen, Tyrel M.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

The Kitaev model is a rare example of an analytically solvable and physically instantiable Hamiltonian yielding a topological quantum spin liquid ground state. Here we report signatures of Kitaev spin liquid physics in the honeycomb magnet $Li_3Co_2SbO_6$, built of high-spin $\it{d^7}$ ($Co^{2+}$) ions, in contrast to the more typical low-spin $\it{d^5}$ electron configurations in the presence of large spin-orbit coupling. Neutron powder diffraction measurements, heat capacity, and magnetization studies support the development of a long-range antiferromagnetic order space group of $\it{C_C}2/\it{m}$, below $\it{T_N}$ = 11 K at $\it{\mu_0H}$ = 0 T. The magnetic entropy recovered between $\it{T}$ = 2 K and 50 K is estimated to be 0.6Rln2, in good agreement with the value expected for systems close to a Kitaev quantum spin liquid state. The temperature-dependent magnetic order parameter demonstrates a $\beta$ value of 0.19(3), consistent with XY anisotropy and in-plane ordering, with Ising-like interactions between layers. Further, we observe a spin-flop driven crossover to ferromagnetic order with space group of $\it{C}2/\it{m}$ under an applied magnetic field of $\it{\mu_0H}$ $\approx$ 0.7 T at $\it{T}$ = 2 K. Magnetic structure analysis demonstrates these magnetic states are competing at finite applied magnetic fields even below the spin-flop transition. Both the $\it{d^7}$ compass model, a quantitative comparison of the specific heat of $Li_3Co_2SbO_6$, and related honeycomb cobaltates to the anisotropic Kitaev model further support proximity to a Kitaev spin liquid state. This material demonstrates the rich playground of high-spin $\it{d^7}$ systems for spin liquid candidates, and complements known $\it{d^5}$ Ir- and Ru-based materials., Comment: 16 pages, 8 figures

Published
2020
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36. Magnetic properties and signatures of ordering in triangular lattice antiferromagnet KCeO2.

Author

Bordelon, Mitchell, Wang, Xiaoling, Pajerowski, Daniel, Banerjee, Arnab, Brown, Craig, Eldeeb, M, Petersen, T, Hozoi, L, Rӧßler, U, Mourigal, Martin, Wilson, Stephen, and Sherwin, Mark

Abstract

The magnetic ground state and the crystalline electric field level scheme of the triangular lattice antiferromagnet KCeO2 are investigated. Below TN=300 mK, KCeO2 develops signatures of magnetic order in specific heat measurements and low energy inelastic neutron scattering data. Trivalent Ce3+ ions in the D3d local environment of this compound exhibit large splittings among the lowest three 4f1 Kramers doublets defining for the free ion the J=5/2 sextet and a ground state doublet with dipole character, consistent with recent theoretical predictions in M. S. Eldeeb et al. Phys. Rev. Materials 4, 124001 (2020). An unexplained, additional local mode appears, and potential origins of this anomalous mode are discussed.

Published
2021

37. Observation of an Intermediate to H2 Binding in a Metal-Organic Framework.

Author

Barnett, Brandon R, Evans, Hayden A, Su, Gregory M, Jiang, Henry ZH, Chakraborty, Romit, Banyeretse, Didier, Hartman, Tyler J, Martinez, Madison B, Trump, Benjamin A, Tarver, Jacob D, Dods, Matthew N, Funke, Lena M, Börgel, Jonas, Reimer, Jeffrey A, Drisdell, Walter S, Hurst, Katherine E, Gennett, Thomas, FitzGerald, Stephen A, Brown, Craig M, Head-Gordon, Martin, and Long, Jeffrey R

Subjects
Chemical Sciences, General Chemistry
Abstract

Coordinatively unsaturated metal sites within certain zeolites and metal-organic frameworks can strongly adsorb a wide array of substrates. While many classical examples involve electron-poor metal cations that interact with adsorbates largely through physical interactions, unsaturated electron-rich metal centers housed within porous frameworks can often chemisorb guests amenable to redox activity or covalent bond formation. Despite the promise that materials bearing such sites hold in addressing myriad challenges in gas separations and storage, very few studies have directly interrogated mechanisms of chemisorption at open metal sites within porous frameworks. Here, we show that nondissociative chemisorption of H2 at the trigonal pyramidal Cu+ sites in the metal-organic framework CuI-MFU-4l occurs via the intermediacy of a metastable physisorbed precursor species. In situ powder neutron diffraction experiments enable crystallographic characterization of this intermediate, the first time that this has been accomplished for any material. Evidence for a precursor intermediate is also afforded from temperature-programmed desorption and density functional theory calculations. The activation barrier separating the precursor species from the chemisorbed state is shown to correlate with a change in the Cu+ coordination environment that enhances π-backbonding with H2. Ultimately, these findings demonstrate that adsorption at framework metal sites does not always follow a concerted pathway and underscore the importance of probing kinetics in the design of next-generation adsorbents.

Published
2021

38. Critical applications of KOCOA in Western Europe, c.26 BC-1745 AD

Author

Brown, Craig James, Ralston, Ian, and Romankiewicz, Tanja

Subjects
Conflict Archaeology, KOCOA, battlefield archaeology, archaeological terrain analysis, battle of Prestonpans, battle of Monte Bernorio, KOCOA assessment
Abstract

In the thirty years since Conflict Archaeology has evolved as a discipline, it has grown exponentially in scope. In order to define a methodological and conceptual framework for the discipline, conflict archaeologists in North America have adopted standard military analytical procedures and terminology. KOCOA (or OAKOC) is the standard military terrain analysis that conflict archaeologists use to aid in defining battlefield boundaries and interpreting battlefield remains. KOCOA is a military acronym that stands for Key or Decisive Terrain; Observation and Fields of Fire; Cover and Concealment; Obstacles; and Avenues of Approach and Withdrawal. The KOCOA approach has been utilized with success within the United States on a number of Revolutionary War, Civil War, and American Frontier Wars battlefields. The National Park Service (NPS) requires the application of KOCOA in evaluating the preservation potential of historic battlefields as part of the American Battlefield Protection Program (ABPP). Conflict Archaeologists have utilized KOCOA without appreciating its full potential or limitations. To date, KOCOA has mostly been applied to terrestrial battlefields that are at least partially preserved or otherwise historically documented. The majority of these projects were conducted under the auspices of the ABPP: the primary interest being the location and evaluation of defining battlefield features. Few attempts have been made to employ KOCOA in an academic setting in order to assess the influence of terrain on the conduct of battles, on command decisions made, or as a tool in the interpretation of archaeological assemblages for the purpose of reconstructing battles that are devoid of direct historical documentation. If KOCOA is to develop as part of the methodological and conceptual framework of Conflict Archaeology, then it needs to be applicable in wider chronological and geographical contexts. This thesis critically evaluates the applicability of KOCOA through answering a varied series of questions across a set of temporally and categorically different Western European sites. In the well documented, early modern Battle of Prestonpans (1745), KOCOA is used to rationalize how the terrain influenced where the actual engagement took place. KOCOA is then utilized to posit the location of the English siege lines and artillery fortifications from the Siege of Edinburgh Castle (1573) that have been subsumed by the urbanization of Edinburgh city center. The Second Scottish War of Independence battlefield at Halidon Hill (1333) is well known, but the battle itself is only documented in secondary chronicles, some written many years after the battle. A KOCOA analysis was conducted to evaluate the accuracy of the chronicles, as well as to show how the English selection of the terrain served as a critical factor in the Scottish defeat. The location of sparsely documented Battle of Dún Nechtain (685) has generated fierce debate among scholars. A KOCOA analysis was undertaken to evaluate the terrain of Dunnichen and Dunachton and demonstrate which may have been the site of the battle. The Roman conquest of the Cantabrian oppidum at Monte Bernorio (c. 26 BC) is not documented in classical sources. Ongoing archaeological excavations at Monte Bernorio have recovered an artifact assemblage that was interpreted through a KOCOA analysis in order to reconstruct the course of the battle. The KOCOA method itself is critically evaluated as an analytical tool based upon the case studies, and it shows that when informed by other components of METT-T, KOCOA is applicable in wide range of chronologically and categorically different sites, both directly documented and undocumented.

Published
2021
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39. What global biogeochemical consequences will marine animal-sediment interactions have during climate change? COMMENT

Author

Bianchi, Thomas S, Aller, Robert C, Atwood, Trisha B, Brown, Craig J, Buatois, Luis A, Levin, Lisa A, Levinton, Jeffrey S, Middelburg, Jack J, Morrison, Elise S, Regnier, Pierre, Shields, Michael R, Snelgrove, Paul VR, Sotka, Erik E, and Stanley, Ryan RE

Subjects
Marine benthos, Carbon cycling, Climate change
Abstract

Benthic animals profoundly influence the cycling and storage of carbon and other elements in marine systems, particularly in coastal sediments. Recent climate change has altered the distribution and abundance of many seafloor taxa and modified the vertical exchange of materials between ocean and sediment layers. Here, we examine how climate change could alter animal-mediated biogeochemical cycling in ocean sediments. The fossil record shows repeated major responses from the benthos during mass extinctions and global carbon perturbations, including reduced diversity, dominance of simple trace fossils, decreased burrow size and bioturbation intensity, and nonrandom extinction of trophic groups. The broad dispersal capacity of many extant benthic species facilitates poleward shifts corresponding to their environmental niche as overlying water warms. Evidence suggests that locally persistent populations will likely respond to environmental shifts through either failure to respond or genetic adaptation rather than via phenotypic plasticity. Regional and global ocean models insufficiently integrate changes in benthic biological activity and their feedbacks on sedimentary biogeochemical processes. The emergence of bioturbation, ventilation, and seafloor-habitat maps and progress in our mechanistic understanding of organism–sediment interactions enable incorporation of potential effects of climate change on benthic macrofaunal mediation of elemental cycles into regional and global ocean biogeochemical models.

Published
2021

40. What global biogeochemical consequences will marine animal–sediment interactions have during climate change?

Author

Bianchi, Thomas S, Aller, Robert C, Atwood, Trisha B, Brown, Craig J, Buatois, Luis A, Levin, Lisa A, Levinton, Jeffrey S, Middelburg, Jack J, Morrison, Elise S, Regnier, Pierre, Shields, Michael R, Snelgrove, Paul VR, Sotka, Erik E, and Stanley, Ryan RE

Subjects
Earth Sciences, Climate Change Impacts and Adaptation, Environmental Sciences, Geology, Life Below Water, Climate Action, Marine benthos, Carbon cycling, Climate change
Abstract

Benthic animals profoundly influence the cycling and storage of carbon and other elements in marine systems, particularly in coastal sediments. Recent climate change has altered the distribution and abundance of many seafloor taxa and modified the vertical exchange of materials between ocean and sediment layers. Here, we examine how climate change could alter animal-mediated biogeochemical cycling in ocean sediments. The fossil record shows repeated major responses from the benthos during mass extinctions and global carbon perturbations, including reduced diversity, dominance of simple trace fossils, decreased burrow size and bioturbation intensity, and nonrandom extinction of trophic groups. The broad dispersal capacity of many extant benthic species facilitates poleward shifts corresponding to their environmental niche as overlying water warms. Evidence suggests that locally persistent populations will likely respond to environmental shifts through either failure to respond or genetic adaptation rather than via phenotypic plasticity. Regional and global ocean models insufficiently integrate changes in benthic biological activity and their feedbacks on sedimentary biogeochemical processes. The emergence of bioturbation, ventilation, and seafloor-habitat maps and progress in our mechanistic understanding of organism–sediment interactions enable incorporation of potential effects of climate change on benthic macrofaunal mediation of elemental cycles into regional and global ocean biogeochemical models.

Published
2021

41. Ambient-Temperature Hydrogen Storage via Vanadium(II)-Dihydrogen Complexation in a Metal–Organic Framework

Author

Jaramillo, David E, Jiang, Henry ZH, Evans, Hayden A, Chakraborty, Romit, Furukawa, Hiroyasu, Brown, Craig M, Head-Gordon, Martin, and Long, Jeffrey R

Subjects
Inorganic Chemistry, Macromolecular and Materials Chemistry, Chemical Sciences, Affordable and Clean Energy, General Chemistry, Chemical sciences, Engineering
Abstract

The widespread implementation of H2 as a fuel is currently hindered by the high pressures or cryogenic temperatures required to achieve reasonable storage densities. In contrast, the realization of materials that strongly and reversibly adsorb hydrogen at ambient temperatures and moderate pressures could transform the transportation sector and expand adoption of fuel cells in other applications. To date, however, no adsorbent has been identified that exhibits a binding enthalpy within the optimal range of -15 to -25 kJ/mol for ambient-temperature hydrogen storage. Here, we report the hydrogen adsorption properties of the metal-organic framework (MOF) V2Cl2.8(btdd) (H2btdd, bis(1H-1,2,3-triazolo[4,5-b],[4',5'-i])dibenzo[1,4]dioxin), which features exposed vanadium(II) sites capable of backbonding with weak π acids. Significantly, gas adsorption data reveal that this material binds H2 with an enthalpy of -21 kJ/mol. This binding energy enables usable hydrogen capacities that exceed that of compressed storage under the same operating conditions. The Kubas-type vanadium(II)-dihydrogen complexation is characterized by a combination of techniques. From powder neutron diffraction data, a V-D2(centroid) distance of 1.966(8) Å is obtained, the shortest yet reported for a MOF. Using in situ infrared spectroscopy, the H-H stretch was identified, and it displays a red shift of 242 cm-1. Electronic structure calculations show that a main contribution to bonding stems from the interaction between the vanadium dπ and H2 σ* orbital. Ultimately, the pursuit of MOFs containing high densities of weakly π-basic metal sites may enable storage capacities under ambient conditions that far surpass those accessible with compressed gas storage.

Published
2021

46. Long range magnetic order in hydroxide layer doped (Li$_{1-x-y}$Fe$_{x}$Mn$_{y}$OD)FeSe

Author

Wilfong, Brandon, Zhou, Xiuquan, Zheng, Huafei, Babra, Navneeth, Brown, Craig M., Lynn, Jeffrey W., Taddei, Keith M., Paglione, Johnpierre, and Rodriguez, Efrain E.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Strongly Correlated Electrons
Abstract

The (Li$_{1-x}$Fe$_{x}$OH)FeSe superconductor has been suspected to exhibit long-range magnetic ordering due to Fe substitution in the LiOH layer. However, no direct observation such as magnetic reflection from neutron diffraction has be reported. Here, we use a chemical design strategy to manipulate the doping level of transition metals in the LiOH layer to tune the magnetic properties of the (Li$_{1-x-y}$Fe$_{x}$Mn$_{y}$OD)FeSe system. We find Mn doping exclusively replaces Li in the hydroxide layer resulting in enhanced magnetization in the (Li$_{0.876}$Fe$_{0.062}$Mn$_{0.062}$OD)FeSe superconductor without significantly altering the superconducting behavior as resolved by magnetic susceptibility and electrical/thermal transport measurements. As a result, long-range magnetic ordering was observed below 12 K with neutron diffraction measurements. This work has implications for the design of magnetic superconductors for the fundamental understanding of superconductivity and magnetism in the iron chalcogenide system as well as exploitation as functional materials for next generation devices.

Published
2019
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48. An Associated Particle Imaging System for Soil-Carbon Measurements

Author

Unzueta, Mauricio Ayllon, Brodie, Eoin, Brown, Craig, Castanha, Cristina, Gary, Charles, Pries, Caitlin Hicks, Larsen, William, Ludewigt, Bernhard, Rosenstrom, Andrew, and Persaud, Arun

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment, Physics - Applied Physics
Abstract

We present first results from experimental data showing the capabilities of an Associated Particle Imaging system to measure carbon in soil and other elements. Specifically, we present results from a pre-mixed soil sample containing pure sand (SiO$_2$) and 4% carbon by weight. Because the main isotopes of all those three elements emit characteristic high-energy gamma rays following inelastic neutron scattering, it is possible to measure their distribution with our instrument. A 3D resolution of several centimeters in all dimensions has been demonstrated.

Published
2019

50. Field-tunable quantum disordered ground state in the triangular lattice antiferromagnet NaYbO$_2$

Author

Bordelon, Mitchell, Kenney, Eric, Hogan, Tom, Posthuma, Lorenzo, Kavand, Marzieh, Lyu, Yuanqi, Sherwin, Mark, Brown, Craig, Graf, M. J., Balents, Leon, and Wilson, Stephen D.

Subjects
Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Other Condensed Matter
Abstract

Antiferromagnetically coupled S=1/2 spins on an isotropic triangular lattice is the paradigm of frustrated quantum magnetism, but structurally ideal realizations are rare. Here we investigate NaYbO$_2$, which hosts an ideal triangular lattice of $J_{eff}=1/2$ moments with no inherent site disorder. No signatures of conventional magnetic order appear down to 50 mK, strongly suggesting a quantum spin liquid ground state. We observe a two-peak specific heat and a nearly quadratic temperature dependence in accord with expectations for a two-dimensional Dirac spin liquid. Application of a magnetic field strongly perturbs the quantum disordered ground state and induces a clear transition into a collinear ordered state consistent with a long-predicted up-up-down structure for a triangular lattice XXZ Hamiltonian driven by quantum fluctuations. The observation of spin liquid signatures in zero field and quantum-induced ordering in intermediate fields in the same compound demonstrate an intrinsically quantum disordered ground state. We conclude that NaYbO$_2$ is a model, versatile platform for exploring spin liquid physics with full tunability of field and temperature., Comment: 14 pages, 4 figures

Published
2019
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