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4. Petrological traverse of the olivine cumulate Séítah formation at Jezero crater, Mars : A perspective from SuperCam onboard Perseverance

Author

Beyssac, O., Forni, O., Cousin, A., Udry, A., Kah, L.C., Mandon, L., Clavé, E., Liu, Y., Poulet, F., Quantin Nataf, C., Gasnault, O., Johnson, J., Benzerara, K., Beck, P., Dehouck, E., Mangold, N., Alvarez Llamas, C., Anderson, R., Arana, G., Barnes, R., Bernard, S., Bosak, T., Brown, A.J., Castro, K., Chide, B., Clegg, S., Cloutis, E., Fouchet, T., Gabriel, T., Gupta, S., Lacombe, G., Lasue, J., Le Mouelic, S., Lopez‐Reyes, G., Madariaga, J.M., McCubbin, F.M., McLennan, S., Manrique, J.A., Meslin, P.Y., Montmessin, F., Núñez, J., Ollila, A.M., Ostwald, A., Pilleri, P., Pinet, P., Royer, C., Sharma, S.K., Schröder, Susanne, Simon, J.I., Toplis, M.J., Veneranda, M., Willis, P.A., Maurice, S., Wiens, R.C., Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Department of Geoscience [Las Vegas], University of Nevada [Las Vegas] (WGU Nevada), Department of Earth and Planetary Sciences [Knoxville], The University of Tennessee [Knoxville], Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centre d'Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Laboratoire de Planétologie et Géosciences - Angers (LPG-ANGERS), Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Department of Analytical Chemistry [Malaga], Universidad de Málaga [Málaga] = University of Málaga [Málaga], Astrogeology Science Center [Flagstaff], United States Geological Survey [Reston] (USGS), Department of Analytical Chemistry [Leioa], University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Department of Earth Science and Engineering [Imperial College London], Imperial College London, Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge] (EAPS), Massachusetts Institute of Technology (MIT), Plancius Research LLC, Los Alamos National Laboratory (LANL), University of Winnipeg, Laboratoire Energie Signal Images et Automatique [Univ Ngaoundéré] (LESIA), Université de Ngaoundéré/University of Ngaoundéré [Cameroun] (UN), Universidad de Valladolid [Valladolid] (UVa), NASA Johnson Space Center (JSC), NASA, Department of Geosciences [Stony Brook], Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Hawaii Institute of Geophysics and Planetology (HIGP), University of Hawai‘i [Mānoa] (UHM), DLR Institute of Optical Sensor Systems, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Department of Earth, Atmospheric, and Planetary Sciences [West Lafayette] (EAPS), and Purdue University [West Lafayette]

Subjects
spectroscopy, LIBS, m2020, Mars, Perseverance, Jezero, Jezero crater, reflectance spectroscopy, in-situ, [SDU]Sciences of the Universe [physics], rover, Seitah, VisIR, Raman, in-situ science
Abstract

International audience; Séítah is the stratigraphically lowest formation visited by Perseverance in the Jezero crater floor. We present the data obtained by SuperCam: texture by imagery, chemistry by LIBS, and mineralogy by VISIR and Raman spectroscopy. The Séítah formation consists of igneous, weakly altered, rocks dominated by millimeter-size grains of olivine with the presence of low-Ca and high-Ca pyroxenes, and other primary minerals (e.g., plagioclase, Cr-Fe-Ti oxides, phosphates). Along a ∼140 m long section in Séítah, SuperCam analyses showed evidence of geochemical and mineralogical variations, from the contact with the overlying Máaz formation, going deeper in the formation. Bulk rock and olivine Mg#, grain size, olivine content increase gradually further from the contact. Along the section, olivine Mg# are not in equilibrium with the bulk rock Mg#, indicating local olivine accumulation. These observations are consistent with Séítah being the deep ultramafic member of a cumulate series derived from the fractional crystallization and slow cooling of the parent magma at depth. Possible magmatic processes and exhumation mechanisms of Séítah are discussed. Séítah rocks show some affinity with some rocks at Gusev crater, and with some martian meteorites suggesting that such rocks are not rare on the surface of Mars. Séítah is part of the Nili Fossae regional olivine-carbonate unit observed from orbit. Future exploration of Perseverance on the rim and outside of the crater will help determine if the observations from the crater floor can be extrapolated to the whole unit, or if this unit is composed of distinct sub-units with various origins.

Published
2023

5. Detecting Facet Joint and Lateral Mass Injuries of the Subaxial Cervical Spine in Major Trauma Patients

Author

Joost Johannes van Middendorp, Ian Cheung, Kristian Dalzell, Hamish Deverall, Brian J.C. Freeman, Stephen A.C. Morris, Simon J.I. Sandler, Richard Williams, Y.H. Yau, and Ben Goss

Subjects
Zygapophyseal joint, Spine, Spinal injuries, Diagnostic imaging, Reproducibility of results, Medicine
Abstract

Study DesignRadiologic imaging measurement study.PurposeTo assess the accuracy of detecting lateral mass and facet joint injuries of the subaxial cervical spine on plain radiographs using computed tomography (CT) scan images as a reference standard; and the integrity of morphological landmarks of the lateral mass and facet joints of the subaxial cervical spine.Overview of LiteratureInjuries of lateral mass and facet joints potentially lead to an unstable subaxial cervical spine and concomitant neurological sequelae. However, no study has evaluated the accuracy of detecting specific facet joint injuries.MethodsEight spinal surgeons scored four sets of the same, randomly re-ordered, 30 cases with and without facet joint injuries of the subaxial cervical spine. Two surveys included conventional plain radiographs series (test) and another two surveys included CT scan images (reference). Facet joint injury characteristics were assessed for accuracy and reliability. Raw agreement, Fleiss kappa, Cohen's kappa and intraclass correlation coefficient statistics were used for reliability analysis. Majority rules were used for accuracy analysis.ResultsOf the 21 facet joint injuries discerned on CT scan images, 10 were detected in both plain radiograph surveys (sensitivity, 0.48; 95% confidence interval [CI], 0.26-0.70). There were no false positive facet joint injuries in either of the first two X-ray surveys (specificity, 1.0; 95% CI, 0.63-1.0). Five of the 11 cases with missed injuries had an injury below the lowest visible articulating level on radiographs. CT scan images resulted in superior inter- and intra-rater agreement values for assessing morphologic injury characteristics of facet joint injuries.ConclusionsPlain radiographs are not accurate, nor reliable for the assessment of facet joint injuries of the subaxial cervical spine. CT scans offer reliable diagnostic information required for the detection and treatment planning of facet joint injuries.

Published
2015
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6. A comparison of the igneous máaz formation at jezero crater with martian meteorites

Author

Udry, A., Ostwald, A., Sautter, V., Cousin, A., Wiens, R. C., Forni, O., Benzerara, K., Beyssac, O., Nachon, M., Dromart, G., Quantin, C., Mandon, L., Clavé, E., Pinet, P., Ollila, A., Bosak, T., Mangold, N., Dehouck, E., Johnson, J., Schmidt, M., Horgan, B., Gabriel, T., Mclennan, S., Maurice, S., Simon, J.I., Herd, C. D. K., M.Madiaraga, J., Brown, A, Connell, S., Flannery, D., Tosca, N., Cohen, B., Liu, Y., Mccubbin, F. M., Cloutis, E., Fouchet, T., Royer, C., Alwmark, S., Sharma, S., Anderson, R., Pilleri, P, University of Nevada [Las Vegas] (WGU Nevada), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Los Alamos National Laboratory (LANL), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Texas A&M University System, École normale supérieure de Lyon (ENS de Lyon), Massachusetts Institute of Technology (MIT), Johns Hopkins University (JHU), Brock University [Canada], Purdue University [West Lafayette], United States Geological Survey (USGS), Stony Brook University [SUNY] (SBU), State University of New York (SUNY), Astromaterials Research and Exploration Science (ARES), NASA Johnson Space Center (JSC), NASA-NASA, University of Alberta, University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), NASA, University of Winnipeg, Queensland University of Technology [Brisbane] (QUT), University of Cambridge [UK] (CAM), California Institute of Technology (CALTECH), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), University of Copenhagen = Københavns Universitet (UCPH), Hawaii Institute of Geophysics and Planetology (HIGP), and University of Hawai‘i [Mānoa] (UHM)

Subjects
jezero crater, [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, [SDU]Sciences of the Universe [physics], rover, mars mineralogy, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, supercam, meteorites
Abstract

International audience

Published
2022

7. Composition and density stratification observed by supercam in the first 300 sols in Jezero crater

Author

Wiens, R.C., Udry, A., Mangold, N., Beyssac, O., Quantin, C., Sautter, V., Cousin, A., Brown, A., Bosak, T., Mandon, L., Forni, O., Johnson, J.R., Mclennan, S., Legett, C., Maurice, S., Mayhew, L., Crumpler, L., Anderson, R.B., Clegg, S.M., Ollila, A.M., Hall, J., Meslin, P.-Y., Kah, L.C., Gabriel, T.S.J., Gasda, P., Simon, J.I., Hausrath, E.M., Horgan, B., Poulet, F., Beck, P., Gupta, S., Chide, B., Clavé, E., Connell, S., Dehouck, E., Dromart, G., Fouchet, T., Royer, C., Frydenvang, J., Gasnault, Olivier, Gibbons, E., Kalucha, H., Lanza, N., Lasue, J., Mouelic, S. Le, Leveillé, R., Cloutis, E., Reyes, G. Lopez, Arana, G., Castro, K., Madariaga, J.M., Manrique, J.-A., Pilorget, C., Pinet, P., Laserna, J., Sharma, S.K., Acosta-Maeda, T., Kelly, E., Montmessin, Franck, Fischer, W., Francis, R., Stack, K., Farley, K., Los Alamos National Laboratory (LANL), Purdue University [West Lafayette], Plancius Research LLC, Laboratoire de Planétologie et Géosciences [UMR_C 6112] (LPG), Université d'Angers (UA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Massachusetts Institute of Technology (MIT), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Johns Hopkins University Applied Physics Laboratory [Laurel, MD] (APL), Stony Brook University [SUNY] (SBU), State University of New York (SUNY), University of Colorado [Boulder], New Mexico Museum of Natural History and Science (NMMNHS), United States Geological Survey (USGS), The University of Tennessee [Knoxville], NASA Johnson Space Center (JSC), NASA, University of Nevada [Las Vegas] (WGU Nevada), Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Grenoble Alpes (UGA), Imperial College London, Université de Bordeaux (UB), University of Winnipeg, Université de Lyon, Observatoire de Paris, Université Paris sciences et lettres (PSL), McGill University = Université McGill [Montréal, Canada], California Institute of Technology (CALTECH), Universidad de Valladolid [Valladolid] (UVa), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Universidad de Málaga [Málaga] = University of Málaga [Málaga], University of Hawaii, PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), and pinet, patrick

Subjects
[SDU] Sciences of the Universe [physics], jezero crater, [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, [SDU]Sciences of the Universe [physics], perseverance in situ exploration, [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU.ASTR.EP] Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], supercam, [SDU.STU.PL] Sciences of the Universe [physics]/Earth Sciences/Planetology, mars geology, mineralogy, petrology
Abstract

International audience

Published
2022

8. A Mars 2020 Perseverance SuperCam Perspective on the Igneous Nature of the Máaz formation at Jezero crater, Mars

Author

Udry, A., Sautter, V., Cousin, A., Wiens, R. C., Forni, O., Benzerara, K., Beyssac, O., Nachon, M., Dromart, G., Quantin, C., Mandon, L., Clavé, E., Pinet, P., Ollila, A., Bosak, T., Mangold, N., Dehouck, E., Johnson, J., Schmidt, M., Horgan, B., Gabriel, T., Mclennan, S., Maurice, S., Simon, J.I., Herd, C., Madiaraga., J. M., University of Nevada [Las Vegas] (WGU Nevada), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Los Alamos National Laboratory (LANL), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure de Lyon (ENS de Lyon), Massachusetts Institute of Technology (MIT), Brock University [Canada], Purdue University [West Lafayette], United States Geological Survey (USGS), Stony Brook University [SUNY] (SBU), State University of New York (SUNY), Astromaterials Research and Exploration Science (ARES), NASA Johnson Space Center (JSC), NASA-NASA, University of Alberta, and University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)

Subjects
Supercam, [SDU.STU.PL]Sciences of the Universe [physics]/Earth Sciences/Planetology, in situ exploration, [SDU]Sciences of the Universe [physics], [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], mars mineralogy, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Perseverance
Abstract

International audience

Published
2022

11. Boron isotopic variations in hydrous rhyolitic melts: a case study from Long Valley, California

Author

Schmitt, A.K. and Simon, J.I.

Subjects
Mineralogy -- Research, Earth sciences
Abstract

In this paper, we present boron isotope analyses of variably degassed rhyolitic glasses from Long Valley, California. The following results indicate that pre-eruptive boron isotopic signatures were preserved in degassed glasses: (1) averaged secondary ionization mass spectrometry (SIMS) measurements of [H.sub.2]O-rich (~3 wt%) melt inclusions from late erupted Bishop Tuff pumice are indistinguishable from positive thermal ionization mass spectrometry (PTIMS) analysis of vesiculated groundmass glass ([[delta].sup.11]B = +5.0 [+ or -] 0.9% and + 5.4 [+ or -] 0.5 [per thousand], respectively); (2) SIMS spot-analyses on [H.sub.2]O-poor obsidian (~0.15 wt% [H.sub.2]O) from younger Glass Mountain Dome YA (average [[delta].sup.11]B = + 5.2 [+ or -] 1.0 [per thousand]) overlap with compositionally similar late Bishop Tuff melt inclusions; and (3) four variably degassed obsidian samples from the 0.6 ka Mono Craters ([H.sub.2]O between 0.74 and 0.10 wt%) are homogeneous with regard to boron (average [[delta].sup.11]B = + 3.2 [+ or -] 0.8 [per thousand], MSWD=0.4). Insignificant variations in [[delta].sup.B] between early and late Bishop Tuff melt inclusion glasses agree with published experimental data that predict minor [sup.11]B depletion in hydrous melts undergoing gas-saturated fractional crystallization. Melt inclusions from two crystal-rich post-caldera lavas (Deer Mountain and South Deadman Dome) are comparatively boron-rich (max. 90 ppm B) and have lower [[delta].sup.11]B values (average [[delta].sup.11]B = + 2.2 [+ or -] 0.8 [per thousand] and -0.4 [+ or -] 1.0 [per thousand]) that are in strong contrast to the boron isotopic composition of post-caldera crystal-poor rhyolites (27 ppm B; [[delta].sup.11]B = + 5.7 [+ or -] 0.8 [per thousand]). These variations in [[delta].sup.11]B are too large to be caused by pre-eruptive degassing. Instead, we favor assimilation of [[delta].sup.11]B depleted low-temperature hydrothermally altered intrusive rocks subsequent to fresh rhyolite recharge.

Published
2004

12. Calcium and neodymium radiogenic isotopes of igneous rocks: Tracing crustal contributions in felsic magmas related to super-eruptions and continental rifting

Author

Mills, R.D., DePaolo, D.J., and Simon, J.I.

Abstract

Radioactive decay of 40K within the continental crust produces a unique Ca isotopic reservoir, with measurable radiogenic 40Ca excesses compared to Earth's mantle (εCa = 0). Thus, igneous rocks with values of εCa > 1 unambiguously indicate a significant old, crustal contribution to their source magma. At our current level of analytical precision, values of εCa < 0.5 are indistinguishable from mantle-like Ca isotope compositions. So, whereas 40Ca excesses clearly define crustal contributions, the source contributions of igneous rocks with mantle-like Ca isotopic composition are less certain. The calcium in these rocks could be derived from partial melting of: young crust, crust with mantle-like K/Ca compositions, or the mantle itself. Here we present Ca isotopic measurements of intermediate to felsic igneous rocks from the western United States, and two crustal xenoliths found within the Fish Canyon Tuff (FCT) of the southern Rocky Mountain volcanic field (SRMVF), USA. Their isotope geochemistry is used to explore their source compositions and to help distinguish new mantle-derived additions to the crust from reworked older crust. Irrespective of age or tectonic setting a majority of the intermediate to silicic igneous rocks studied exhibit mantle-like Ca isotope compositions. Mantle-like Ca isotopic data for leucogranites associated with the beginning of Rio Grande rifting in Colorado indicate that felsic melts were generated from newly formed lower crust related to earlier calc-alkaline magmatism. These data also indicate that the Nd isotopic signature in early rift magmas is controlled by the lithospheric mantle, even if the major mantle source reservoir is the asthenospheric mantle. The two crustal xenoliths found within the 28.2 Ma FCT yield εCa values of 3.6 and 7.0, respectively. The 40Ca excesses of these Precambrian source rocks are supported by K–Ca geochronology. However, like several other ignimbrites from the SRMVF and from Yellowstone, USA, the FCT (εCa ∼ 0.3) has a Ca isotope composition that is indistinguishable from the mantle. Nd isotopic analyses of the FCT imply that it was generated from 10–75% of an enriched component, and so the Ca isotopic data appear to restrict that component to newly formed lower crust, low K/Ca crust, or enriched mantle. Contrary to these findings, several large ignimbrites and one granitoid from the SRMVF show significant 40Ca excesses. These tuffs (Wall Mountain, Blue Mesa, and Grizzly Peak) and one granitoid (Mt. Princeton) are sourced from near, or within the Colorado Mineral Belt. Collectively, these data indicate that felsic, Precambrian crust likely contributed less than 50% of the material to the petrogenesis of many of the large ignimbrites that have erupted across the western United States. However, the crustal components that contributed to magmas in the Colorado Mineral Belt have 40Ca excesses; consistent with felsic, Precambrian crust.

Published
2018
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13. Traumatic subaxial cervical facet subluxation and dislocation: epidemiology, radiographic analyses, and risk factors for spinal cord injury

Author

Petar Tcherveniakov, John J. Costi, Claire F. Jones, Ryan D. Quarrington, Simon J.I. Sandler, Shabnam Torabiardakani, Jillian Clark, Yu Chao Lee, and Brian J. C. Freeman

Subjects
Adult, Male, Facet (geometry), medicine.medical_specialty, Epidemiology, Radiography, Joint Dislocations, Context (language use), Spinal cord injury, 03 medical and health sciences, 0302 clinical medicine, Spinal cord compression, Medicine, Humans, Orthopedics and Sports Medicine, Spinal canal, Cervical facet dislocation, Spinal Cord Injuries, Aged, Subluxation, 030222 orthopedics, business.industry, Glasgow Coma Scale, Radiographic analysis, Middle Aged, medicine.disease, Magnetic Resonance Imaging, Distractive flexion injury, Surgery, medicine.anatomical_structure, Cervical Vertebrae, Spinal Fractures, Female, Neurology (clinical), Risk factor, business, Tomography, X-Ray Computed, 030217 neurology & neurosurgery
Abstract

© 2017 Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license: http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (July 2017) in accordance with the publisher’s archiving policy, Background Context Distractive flexion injuries (DFIs) of the subaxial cervical spine are major contributors to spinal cord injury (SCI). Prompt assessment and early intervention of DFIs associated with SCI are crucial to optimize patient outcome; however, neurologic examination of patients with subaxial cervical injury is often difficult, as patients commonly present with reduced levels of consciousness. Therefore, it is important to establish potential associations between injury epidemiology and radiographic features, and neurologic involvement. Purpose The aims of this study were to describe the epidemiology and radiographic features of DFIs presenting to a major Australian tertiary hospital and to identify those factors predictive of SCI. The agreement and repeatability of radiographic measures of DFI severity were also investigated. Study Design/Setting This is a combined retrospective case-control and reliability-agreement study. Patient Sample Two hundred twenty-six patients (median age 40 years [interquartile range = 34]; 72.1% male) who presented with a DFI of the subaxial cervical spine between 2003 and 2013 were reviewed. Outcome Measures The epidemiology and radiographic features of DFI, and risk factors for SCI were identified. Inter- and intraobserver agreement of radiographic measurements was evaluated. Methods Medical records, radiographs, and computed tomography and magnetic resonance imaging scans were examined, and the presence of SCI was evaluated. Radiographic images were analyzed by two consultant spinal surgeons, and the degree of vertebral translation, facet apposition, spinal canal occlusion, and spinal cord compression were documented. Multivariable logistic regression models identified epidemiology and radiographic features predictive of SCI. Intraclass correlation coefficients (ICCs) examined inter- and intraobserver agreement of radiographic measurements. Results The majority of patients (56.2%) sustained a unilateral (51.2%) or a bilateral facet (48.8%) dislocation. The C6–C7 vertebral level was most commonly involved (38.5%). Younger adults were over-represented among motor-vehicle accidents, whereas falls contributed to a majority of DFIs sustained by older adults. Greater vertebral translation, together with lower facet apposition, distinguished facet dislocation from subluxation. Dislocation, bilateral facet injury, reduced Glasgow Coma Scale, spinal canal occlusion, and spinal cord compression were predictive of neurologic deficit. Radiographic measurements demonstrated at least a “moderate” agreement (ICC>0.4), with most demonstrating an “almost perfect” reproducibility. Conclusions This large-scale cohort investigation of DFIs in the cervical spine describes radiographic features that distinguish facet dislocation from subluxation, and associates highly reproducible anatomical and clinical indices to the occurrence of concomitant SCI.

Published
2017

14. Water in alkali feldspar: The effect of rhyolite generation on the lunar hydrogen budget

Author

Simon, J.I., Hauri, E.H., Wang, J., Alexander, C.M., and Mills, R.D.

Abstract

Recent detection of indigenous hydrogen in a diversity of lunar materials, including volcanic glass (Saal et al., 2008), melt inclusions (Hauri et al., 2011), apatite (Boyce et al., 2010; McCubbin et al., 2010), and plagioclase (Hui et al., 2013) suggests water played a role in the chemical differentiation of the Moon. Water contents measured in plagioclase feldspar, a dominant mineral in the ancient crustal lunar highlands have been used to predict that 320 ppm water initially existed in the lunar magma ocean (Hui et al., 2013) whereas measurements in apatite, found as a minor mineral in lunar rocks, representing younger potassium-enriched melt predict a bulk Moon with

Published
2017
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18. Adult supratentorial primitive neuroectodermal tumour presenting as intracranial haemorrhage: Case report

Author

Simon J.I. Sandler, Adam J. Wells, Sophia Otto, and Sean P. Black-Tiong

Subjects
Adult, medicine.medical_specialty, Pathology, Intracranial haemorrhage, Adult population, Raised intracranial pressure, 03 medical and health sciences, 0302 clinical medicine, Physiology (medical), medicine, Humans, Neuroectodermal Tumors, Primitive, Young adult, Primitive neuroectodermal tumour, business.industry, Supratentorial Neoplasms, General Medicine, Supratentorial primitive neuroectodermal tumour, Neurology, 030220 oncology & carcinogenesis, Female, Surgery, Neurology (clinical), Radiology, Presentation (obstetrics), business, Intracranial Hemorrhages, 030217 neurology & neurosurgery
Abstract

Primitive neuroectodermal tumours (PNET) are highly malignant tumours with an aggressive clinical behaviour. Commonly seen in children, they are uncommon in the adult population, and rare in the supratentorial location. Adult supratentorial PNETs (ST-PNET) typically present with symptoms relating to raised intracranial pressure, seizures, or focal neurological deficits. Presentation with intracranial haemorrhage has been reported only twice before in the literature, one of which was fatal. We report the case of intracranial haemorrhage secondary to ST-PNET in a young adult and her immediate management.

Published
2017

21. Most Cited Publications in Cervical Spine Surgery

Author

Simon J.I. Sandler, Yun-Hom Yau, Yu Chao Lee, Brian J. C. Freeman, Michael Selby, and Francis Brooks

Subjects
Cervical spine surgery, 030222 orthopedics, medicine.medical_specialty, Joint surgery, Web of science, business.industry, General surgery, Cervical spine fusion, Articles, Cervical spine, Surgery, 03 medical and health sciences, 0302 clinical medicine, Citation analysis, medicine, Orthopedics and Sports Medicine, Citation, business, 030217 neurology & neurosurgery
Abstract

Purpose The purpose of this study is to perform a citation analysis on the most frequently cited articles in the topic of cervical spine surgery and report on the top 100 most cited publication in this topic. Methods We used the Thomson Reuters Web of Science to search citations of all articles from 1945 to 2015 relevant to cervical spine surgery and ranked them according to the number of citations. The 100 most cited articles that matched the search criteria were further analyzed by number of citations, first author, journal, year of publication, country and institution of origin. Results The top 100 cited articles in the topic of cervical spine surgery were published from 1952-2011. The number of citations ranged from 106 times for the 100th paper to 1206 times for the top paper. The decade of 1990-1999 saw the most publications. The Journal of Spine published the most articles, followed by Journal of Bone and Joint Surgery America. Investigators from America authored the most papers and The University of California contributed the most publications. Cervical spine fusion was the most common topic published with 36 papers, followed by surgical technique and trauma. Conclusion This article identifies the 100 most cited articles in cervical spine surgery. It has provided insight to the history and development in cervical spine surgery and many of which have shaped the way we practice today.

Published
2017

23. Lumbosacral epidural lipomatosis causing rapid onset cauda equina syndrome

Author

Simon J.I. Sandler, Adam J. Wells, Nikitas J. Vrodos, and Matthew J. McDonald

Subjects
musculoskeletal diseases, Epidural Space, Male, medicine.medical_specialty, Lipomatosis, Cauda equina syndrome, Surgical decompression, Physiology (medical), medicine, Humans, Polyradiculopathy, business.industry, General Medicine, Middle Aged, medicine.disease, Decompression, Surgical, Magnetic Resonance Imaging, Surgery, Epidural lipomatosis, Spinal epidural, Neurology, Steroid use, Rapid onset, Neurology (clinical), business, Lumbosacral joint
Abstract

Spinal epidural lipomatosis (SEL) is a rare cause of cauda equina syndrome (CES), which must be diagnosed with MRI in conjunction with a high level of clinical suspicion. Most reported cases are associated with obesity, steroid use or are secondary to endocrinopathies, frequently present subacutely or chronically, and have been managed with both surgical decompression and non-operative measures. We describe an obese 55-year-old man with rapid onset CES secondary to idiopathic lumbosacral SEL which was managed successfully with surgical decompression. Although often thought to be a trivial radiological finding, it is important not to be dismissive of patients presenting with compressive neuropathy and MRI evidence of space-occupying SEL.

Published
2013

26. Integrated experimental and numerical assessment of acid buffer capacity evolution in soils.

Author

Wendlandt R.F., Tailings and mine waste '98 Fort Collins, Colorado 26-Jan-9828-Jan-98, Chastain E.A., Harrison W.J., Jecha-Ernstberger J., Simon J.I., Wendlandt R.F., Tailings and mine waste '98 Fort Collins, Colorado 26-Jan-9828-Jan-98, Chastain E.A., Harrison W.J., Jecha-Ernstberger J., and Simon J.I.

Abstract

Agricultural soils in the arid San Luis Valley, Colorado, receive irrigation water from several sources including metal-rich waters of natural and mining origin. Assessment of acid-buffering capacity loss in these soils required an integrated experimental and numerical approach to evaluate multiple variables including soil composition, acidity of irrigation water and rate of application. Sequential batch tests were designed to evaluate the effects of total acid loading on the soils and long term batch tests were also carried out. A four-step sequential extraction scheme was used in evaluating the mode of occurrence and concentrations of metals in soils before and after acid reaction. Experimental data were used to calibrate reaction path models., Agricultural soils in the arid San Luis Valley, Colorado, receive irrigation water from several sources including metal-rich waters of natural and mining origin. Assessment of acid-buffering capacity loss in these soils required an integrated experimental and numerical approach to evaluate multiple variables including soil composition, acidity of irrigation water and rate of application. Sequential batch tests were designed to evaluate the effects of total acid loading on the soils and long term batch tests were also carried out. A four-step sequential extraction scheme was used in evaluating the mode of occurrence and concentrations of metals in soils before and after acid reaction. Experimental data were used to calibrate reaction path models.

Published
1998

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