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Giannopoulos AA, Keller L, Sepulcri D, Boehm R, Garefa C, Venugopal P, Mitra J, Ghose S, Deak P, Pack JD, Davis CL, Stähli BE, Stehli J, Pazhenkottil AP, Kaufmann PA, Buechel RR. High-Speed On-Site Deep Learning-Based FFR-CT Algorithm: Evaluation Using Invasive Angiography as the Reference Standard. AJR Am J Roentgenol 2023; 221:460-470. [PMID: 37132550 DOI: 10.2214/ajr.23.29156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
BACKGROUND. Estimation of fractional flow reserve from coronary CTA (FFR-CT) is an established method of assessing the hemodynamic significance of coronary lesions. However, clinical implementation has progressed slowly, partly because of off-site data transfer with long turnaround times for results. OBJECTIVE. The purpose of this study was to evaluate the diagnostic performance of FFR-CT computed on-site with a high-speed deep learning-based algorithm with invasive hemodynamic indexes as the reference standard. METHODS. This retrospective study included 59 patients (46 men, 13 women; mean age, 66.5 ± 10.2 years) who underwent coronary CTA (including calcium scoring) followed within 90 days by invasive angiography with invasive fractional flow reserve (FFR) and/or instantaneous wave-free ratio measurements from December 2014 to October 2021. Coronary artery lesions were considered to have hemodynamically significant stenosis in the presence of invasive FFR of 0.80 or less and/or instantaneous wave-free ratio of 0.89 or less. A single cardiologist evaluated the CTA images using an on-site deep learning-based semiautomated algorithm entailing a 3D computational flow dynamics model to determine FFR-CT for coronary artery lesions detected with invasive angiography. Time for FFR-CT analysis was recorded. FFR-CT analysis was repeated by the same cardiologist in 26 randomly selected examinations and by a different cardiologist in 45 randomly selected examinations. Diagnostic performance and agreement were assessed. RESULTS. A total of 74 lesions were identified with invasive angiography. FFR-CT and invasive FFR had strong correlation (r = 0.81) and, in Bland-Altman analysis, bias of 0.01 and 95% limits of agreement of -0.13 to 0.15. FFR-CT had AUC for hemodynamically significant stenosis of 0.975. At a cutoff of 0.80 or less, FFR-CT had 95.9% accuracy, 93.5% sensitivity, and 97.7% specificity. In 39 lesions with severe calcifications (≥ 400 Agatston units), FFR-CT had AUC of 0.991 and at a cutoff of 0.80, 94.7% sensitivity, 95.0% specificity, and 94.9% accuracy. Mean analysis time per patient was 7 minutes 54 seconds. Intraobserver agreement (intraclass correlation coefficient, 0.85; bias, -0.01; 95% limits of agreement, -0.12 and 0.10) and interobserver agreement (intraclass correlation coefficient, 0.94; bias, -0.01; 95% limits of agreement, -0.08 and 0.07) were good to excellent. CONCLUSION. A high-speed on-site deep learning-based FFR-CT algorithm had excellent diagnostic performance for hemodynamically significant stenosis with high reproducibility. CLINICAL IMPACT. The algorithm should facilitate implementation of FFR-CT technology into routine clinical practice.
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Affiliation(s)
- Andreas A Giannopoulos
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | - Lukas Keller
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | - Daniel Sepulcri
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | - Reto Boehm
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | - Chrysoula Garefa
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | | | | | | | | | | | | | - Barbara E Stähli
- Department of Cardiology, University Heart Center, University Hospital Zurich, Zurich, Switzerland
| | - Julia Stehli
- Department of Cardiology, University Heart Center, University Hospital Zurich, Zurich, Switzerland
| | - Aju P Pazhenkottil
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | - Philipp A Kaufmann
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
| | - Ronny R Buechel
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, Zurich 8091, Switzerland
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Darras H, Berney C, Hasin S, Drescher J, Feldhaar H, Keller L. Obligate chimerism in male yellow crazy ants. Science 2023; 380:55-58. [PMID: 37023182 DOI: 10.1126/science.adf0419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
Multicellular organisms typically develop from a single fertilized egg and therefore consist of clonal cells. We report an extraordinary reproductive system in the yellow crazy ant. Males are chimeras of haploid cells from two divergent lineages: R and W. R cells are overrepresented in the males' somatic tissues, whereas W cells are overrepresented in their sperm. Chimerism occurs when parental nuclei bypass syngamy and divide separately within the same egg. When syngamy takes place, the diploid offspring either develops into a queen when the oocyte is fertilized by an R sperm or into a worker when fertilized by a W sperm. This study reveals a mode of reproduction that may be associated with a conflict between lineages to preferentially enter the germ line.
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Affiliation(s)
- H Darras
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - C Berney
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - S Hasin
- Valaya Alongkorn Rajabhat University, Pathum Thani, Thailand
| | - J Drescher
- Department of Animal Ecology, Göttingen University, Göttingen, Germany
| | - H Feldhaar
- Department of Animal Ecology, Göttingen University, Göttingen, Germany
- Animal Ecology I, University of Bayreuth, Bayreuth, Germany
| | - L Keller
- Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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Maity SR, Ceretti M, De Barros R, Keller L, Schefer J, Cervellino A, Rodríguez Velamazan JA, Paulus W. Large-scale oxygen order phase transitions and fast ordering kinetics at moderate temperatures in Nd 2NiO 4+δ electrodes. Mater Adv 2023; 4:651-661. [PMID: 36741973 PMCID: PMC9869455 DOI: 10.1039/d2ma00833e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 12/12/2022] [Indexed: 06/18/2023]
Abstract
Non-stoichiometric 214-nickelates with Ruddlesden-Popper (RP) type frameworks emerged as potential candidates for mixed electronic/ionic conductors in the intermediate temperature range. In this work we investigated structural aspects of the oxygen ion mobility diffusion mechanisms in non-stoichiometric Nd2NiO4+δ nickelates by X-ray (laboratory and synchrotron) as well by neutron diffraction. Temperature dependent synchrotron powder diffraction revealed a phase diagram of unprecedented complexity, involving a series of highly organized, 3D modulated phases related to oxygen ordering below 800 K. All phase transitionsimply translational periodicities exceeding 100 Å, and are found to be of 1st order, together with fast ordering kinetics. These surprising structural correlations, induced by the presence of interstitial oxygen atoms, suggest a collective phason-like oxygen diffusion mechanism together with dynamical contributions from the aperiodical lattice creating shallow diffusion pathways down to room temperature.
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Affiliation(s)
- Sumit Ranjan Maity
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut Villigen CH-5232 Switzerland
- University of Geneva, Department of Quantum Matter Physics (DQMP) 24, Quai Ernest Ansermet CH-1211 Genève 4 Switzerland
| | | | | | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut Villigen CH-5232 Switzerland
| | - Jürg Schefer
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut Villigen CH-5232 Switzerland
| | | | | | - Werner Paulus
- ICGM, Univ. Montpellier, CNRS, ENSCM Montpellier France
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4
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Keller L, Rabinovitch N. POST COVID RECURRENT FEVER IN A CHILD WITH GENETIC SUSCEPTIBILITY TO FAMILIAL MEDITERRANEAN FEVER. Ann Allergy Asthma Immunol 2022. [DOI: 10.1016/j.anai.2022.08.972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Schneider S, Robador J, Mayer F, Feinauer M, Keller L, Pantel K, Stadler J, Gorzelanny C, Winkler F, Bauer A. OC-03: Platelet-derived von Willebrand factor is involved in thrombosis and metastatic growth of melanoma in the brain. Thromb Res 2022. [DOI: 10.1016/s0049-3848(22)00175-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Pomjakushin V, Perez-Mato JM, Fischer P, Keller L, Sikora W. Revisiting the antiferromagnetic structure of Tb 14Ag 51: the importance of distinguishing alternative symmetries for a multidimensional order parameter. Acta Crystallogr B Struct Sci Cryst Eng Mater 2022; 78:172-178. [PMID: 35411856 DOI: 10.1107/s205252062200124x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 02/01/2022] [Indexed: 06/14/2023]
Abstract
The antiferromagnetic structure of Tb14Ag51 with the propagation vector [1/3, 1/3, 0] and the parent space group P6/m is revisited using both magnetic symmetry and irreducible representation arguments. A new magnetic structure under the hexagonal Shubnikov magnetic space group P6' which fits much better the experimental data is found. This new solution was obtained by constraining the spin arrangement to one of the three possible magnetic space groups of maximal symmetry that can be realized by a magnetic ordering transforming according to the four-dimensional physically irreducible representation that is known to be relevant in this magnetic phase. The refined model, parameterized under P6', implicitly includes the presence of a third harmonic with the propagation vector at the gamma point [0, 0, 0], which has an important weight in the final result. The structure consists of 13 symmetry-independent Tb magnetic moments with the same size of 8.48 (2) μB, propagating cycloidally in the ab plane. The modulation has a substantial deviation from being purely sinusoidal due to the contribution of the mentioned third harmonic.
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Affiliation(s)
- Vladimir Pomjakushin
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Juan Manuel Perez-Mato
- Facultad de Ciencia y Tecnologa, Universidad del Pas Vasco, UPV/EHU, Apartado 644, E-48080 Bilbao, Spain
| | - Peter Fischer
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institut (PSI), CH-5232 Villigen, Switzerland
| | - Wiesława Sikora
- Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, PL-30-059 Krakow, Poland
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7
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Klein YM, Gawryluk DJ, Shang T, Sheptyakov D, Pomjakushin V, Keller L, Casati N, Lacorre P, Fernández-Díaz MT, Rodríguez-Carvajal J, Medarde M. Distortion mode anomalies at T
MIT = T
N in bulk PrNiO3. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321089522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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8
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Lohr JH, Larralde AL, Curiale J, Sánchez RD, Campo J, Cuello GJ, Sheptyakov D, Keller L, Kenzelmann M, Aurelio G. Novel incommensurate magnetic phase in the magnetoelectric Sr-doped cobaltate CaBaCo4O7. Acta Crystallogr A Found Adv 2021. [DOI: 10.1107/s0108767321094575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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9
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Seitz J, Keller L, Trinh S, Herpertz-Dahlmann B. [Gut microbiome and anorexia nervosa : The relationship between microbiome and gut-brain interaction in the context of anorexia nervosa]. Nervenarzt 2020; 91:1115-1121. [PMID: 33034670 DOI: 10.1007/s00115-020-01003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/07/2020] [Indexed: 10/23/2022]
Abstract
In recent years the intestinal microbiome and its interaction with the brain has aroused a growing interest. The findings gained in the course of this research are of great relevance not only to basic scientists but also to clinicians, as studies suggest an association between an altered microbiome and various somatic (e.g. chronic inflammatory intestinal diseases, obesity and diabetes) as well as psychiatric diseases (e.g. anxiety disorders, depression). In addition to a direct influence of the microbiome on the brain and behavior, various mechanisms seem to be relevant, including altered energy intake from food, hormonal changes, probably increased intestinal permeability as well as inflammatory and immunological processes. Anorexia nervosa (AN) is the third most common chronic disease in adolescence and has the highest mortality rate among all mental disorders. In addition to extremely restrictive eating habits, weight loss and comorbid anxiety and depression symptoms, endocrine changes and an increased autoimmune and inflammatory response are characteristic. Since AN is particularly strongly linked to eating behavior and nutrition, research into the microbiome seems very promising, especially with respect to this disease. This article gives a first insight into the underlying processes that play a role in gut-brain interaction in the context of AN and summarizes the previous empirical findings on this topic. Finally, an outlook on future research and possible implications for the therapeutic practice and treatment of AN is given.
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Affiliation(s)
- J Seitz
- Klinik für Psychiatrie, Psychosomatik und Psychotherapie des Kindes- und Jugendalters, Uniklinik RWTH Aachen, Neuenhofer Weg 21, 52074, Aachen, Deutschland.
| | - L Keller
- Klinik für Psychiatrie, Psychosomatik und Psychotherapie des Kindes- und Jugendalters, Uniklinik RWTH Aachen, Neuenhofer Weg 21, 52074, Aachen, Deutschland
| | - S Trinh
- Institut für Neuroanatomie, Uniklinik RWTH Aachen, Aachen, Deutschland
| | - B Herpertz-Dahlmann
- Klinik für Psychiatrie, Psychosomatik und Psychotherapie des Kindes- und Jugendalters, Uniklinik RWTH Aachen, Neuenhofer Weg 21, 52074, Aachen, Deutschland
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10
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Keller L, Link T, Wimberger P. Zielgerichtete Therapie des fortgeschrittenen Endometriumkarzinoms. Geburtshilfe Frauenheilkd 2020. [DOI: 10.1055/s-0040-1718286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- L Keller
- Department of Gynecology and Obstetrics, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden
- National Center for Tumor Diseases (NCT), German Cancer Research Center (DKFZ), Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden
- German Cancer Consortium (DKTK), and German Cancer Research Center (DKFZ)
| | - T. Link
- Department of Gynecology and Obstetrics, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden
- National Center for Tumor Diseases (NCT), German Cancer Research Center (DKFZ), Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden
- German Cancer Consortium (DKTK), and German Cancer Research Center (DKFZ)
| | - P Wimberger
- Department of Gynecology and Obstetrics, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden
- National Center for Tumor Diseases (NCT), German Cancer Research Center (DKFZ), Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden
- German Cancer Consortium (DKTK), and German Cancer Research Center (DKFZ)
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11
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Liu X, Feng X, Meihaus KR, Meng X, Zhang Y, Li L, Liu J, Pedersen KS, Keller L, Shi W, Zhang Y, Cheng P, Long JR. Coercive Fields Above 6 T in Two Cobalt(II)–Radical Chain Compounds. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202002673] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Xiaoqing Liu
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Tianjin 300071 China
| | - Xiaowen Feng
- Department of Chemistry University of California Berkeley CA 94720 USA
| | - Katie R. Meihaus
- Department of Chemistry University of California Berkeley CA 94720 USA
| | - Xixi Meng
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Tianjin 300071 China
| | - Yuan Zhang
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Tianjin 300071 China
| | - Liang Li
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Tianjin 300071 China
| | - Jun‐Liang Liu
- Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of Chemistry Sun Yat-Sen University Guangzhou 510275 China
| | - Kasper S. Pedersen
- Department of Chemistry Technical University of Denmark DK-2800 Kgs. Lyngby Denmark
| | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging Paul Scherrer Institute CH-5232 Villigen PSI Switzerland
| | - Wei Shi
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Tianjin 300071 China
| | - Yi‐Quan Zhang
- Jiangsu Key Laboratory for NSLSCS School of Physical Science and Technology Nanjing Normal University Nanjing 210023 China
| | - Peng Cheng
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center College of Chemistry Nankai University Tianjin 300071 China
| | - Jeffrey R. Long
- Department of Chemistry University of California Berkeley CA 94720 USA
- Department of Chemical and Biomolecular Engineering University of California Berkeley CA 94720 USA
- Materials Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
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12
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Liu X, Feng X, Meihaus KR, Meng X, Zhang Y, Li L, Liu JL, Pedersen KS, Keller L, Shi W, Zhang YQ, Cheng P, Long JR. Coercive Fields Above 6 T in Two Cobalt(II)-Radical Chain Compounds. Angew Chem Int Ed Engl 2020; 59:10610-10618. [PMID: 32285987 DOI: 10.1002/anie.202002673] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Indexed: 11/09/2022]
Abstract
Lanthanide permanent magnets are widely used in applications ranging from nanotechnology to industrial engineering. However, limited access to the rare earths and rising costs associated with their extraction are spurring interest in the development of lanthanide-free hard magnets. Zero- and one-dimensional magnetic materials are intriguing alternatives due to their low densities, structural and chemical versatility, and the typically mild, bottom-up nature of their synthesis. Here, we present two one-dimensional cobalt(II) systems Co(hfac)2 (R-NapNIT) (R-NapNIT=2-(2'-(R-)naphthyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, R=MeO or EtO) supported by air-stable nitronyl nitroxide radicals. These compounds are single-chain magnets and exhibit wide, square magnetic hysteresis below 14 K, with giant coercive fields up to 65 or 102 kOe measured using static or pulsed high magnetic fields, respectively. Magnetic, spectroscopic, and computational studies suggest that the record coercivities derive not from three-dimensional ordering but from the interaction of adjacent chains that compose alternating magnetic sublattices generated by crystallographic symmetry.
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Affiliation(s)
- Xiaoqing Liu
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Xiaowen Feng
- Department of Chemistry, University of California, Berkeley, CA, 94720, USA
| | - Katie R Meihaus
- Department of Chemistry, University of California, Berkeley, CA, 94720, USA
| | - Xixi Meng
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Yuan Zhang
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Liang Li
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Jun-Liang Liu
- Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Kasper S Pedersen
- Department of Chemistry, Technical University of Denmark, DK-2800, Kgs. Lyngby, Denmark
| | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - Wei Shi
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing, 210023, China
| | - Peng Cheng
- Key Laboratory of Advanced Energy Materials Chemistry (MOE), Renewable Energy Conversion and Storage Center, College of Chemistry, Nankai University, Tianjin, 300071, China
| | - Jeffrey R Long
- Department of Chemistry, University of California, Berkeley, CA, 94720, USA.,Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720, USA.,Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
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Sibille R, Gauthier N, Lhotel E, Porée V, Pomjakushin V, Ewings RA, Perring TG, Ollivier J, Wildes A, Ritter C, Hansen TC, Keen DA, Nilsen GJ, Keller L, Petit S, Fennell T. A quantum liquid of magnetic octupoles on the pyrochlore lattice. Nat Phys 2020; 16:546-552. [PMID: 32802143 PMCID: PMC7115929 DOI: 10.1038/s41567-020-0827-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 02/05/2020] [Indexed: 06/11/2023]
Abstract
Spin liquids are highly correlated yet disordered states formed by the entanglement of magnetic dipoles1. Theories define such states using gauge fields and deconfined quasiparticle excitations that emerge from a local constraint governing the ground state of a frustrated magnet. For example, the '2-in-2-out' ice rule for dipole moments on a tetrahedron can lead to a quantum spin ice2-4 in rare-earth pyrochlores. However, f-electron ions often carry multipole degrees of freedom of higher rank than dipoles, leading to intriguing behaviours and 'hidden' orders5-6. Here we show that the correlated ground state of a Ce3+-based pyrochlore, Ce2Sn2O7, is a quantum liquid of magnetic octupoles. Our neutron scattering results are consistent with a fluid-like state where degrees of freedom have a more complex magnetization density than that of magnetic dipoles. The nature and strength of the octupole-octupole couplings, together with the existence of a continuum of excitations attributed to spinons, provides further evidence for a quantum ice of octupoles governed by a '2-plus-2-minus' rule7-8. Our work identifies Ce2Sn2O7 as a unique example of frustrated multipoles forming a 'hidden' topological order, thus generalizing observations on quantum spin liquids to multipolar phases that can support novel types of emergent fields and excitations.
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Affiliation(s)
- Romain Sibille
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Nicolas Gauthier
- Stanford Institute for Materials and Energy Science, SLAC National Accelerator Laboratory and Stanford University, Menlo Park, California 94025, USA
| | - Elsa Lhotel
- Institut Néel, CNRS–Université Joseph Fourier, 38042 Grenoble, France
| | - Victor Porée
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Vladimir Pomjakushin
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Russell A. Ewings
- ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Toby G. Perring
- ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Jacques Ollivier
- Institut Laue-Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Andrew Wildes
- Institut Laue-Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Clemens Ritter
- Institut Laue-Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Thomas C. Hansen
- Institut Laue-Langevin, 71 avenue des Martyrs, 38000 Grenoble, France
| | - David A. Keen
- ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Gøran J. Nilsen
- ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Harwell Campus, Didcot, OX11 0QX, UK
| | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Sylvain Petit
- LLB, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Tom Fennell
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
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14
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Gehr B, Bonnot NC, Heurich M, Cagnacci F, Ciuti S, Hewison AJM, Gaillard J, Ranc N, Premier J, Vogt K, Hofer E, Ryser A, Vimercati E, Keller L. Stay home, stay safe—Site familiarity reduces predation risk in a large herbivore in two contrasting study sites. J Anim Ecol 2020; 89:1329-1339. [DOI: 10.1111/1365-2656.13202] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 01/22/2020] [Indexed: 01/26/2023]
Affiliation(s)
- Benedikt Gehr
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
- Centre d’Ecologie Fonctionnelle et Evolutive UMR 5175 CNRS ‐ Université de Montpellier ‐ Université Paul‐Valéry Montpellier ‐ EPHE Montpellier Cedex 5 France
| | | | - Marco Heurich
- Department of Visitor Management and National Park Monitoring Bavarian Forest National Park Grafenau Germany
- Wildlife Ecology and Wildlife Management Faculty of Environment and Natural Resources University of Freiburg Freiburg Germany
| | - Francesca Cagnacci
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre Fondazione Edmund Mach Trentino Italy
- Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA
| | - Simone Ciuti
- School of Biology and Environmental Science University College Dublin Science Centre ‐ West Dublin Ireland
| | | | - Jean‐Michel Gaillard
- Unité Mixte de Recherche CNRS‐Université Lyon 1 N85558 ‘Biométrie et Biologie Evolutive’ Villeurbanne Cedex France
| | - Nathan Ranc
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre Fondazione Edmund Mach Trentino Italy
- Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA
| | - Joe Premier
- Department of Visitor Management and National Park Monitoring Bavarian Forest National Park Grafenau Germany
- Wildlife Ecology and Wildlife Management Faculty of Environment and Natural Resources University of Freiburg Freiburg Germany
| | - Kristina Vogt
- KORACarnivore Ecology and Wildlife Management Muri Switzerland
| | - Elizabeth Hofer
- KORACarnivore Ecology and Wildlife Management Muri Switzerland
| | - Andreas Ryser
- KORACarnivore Ecology and Wildlife Management Muri Switzerland
| | - Eric Vimercati
- KORACarnivore Ecology and Wildlife Management Muri Switzerland
| | - Lukas Keller
- Department of Evolutionary Biology and Environmental Studies University of Zurich Zurich Switzerland
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15
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Guguchia Z, Verezhak JAT, Gawryluk DJ, Tsirkin SS, Yin JX, Belopolski I, Zhou H, Simutis G, Zhang SS, Cochran TA, Chang G, Pomjakushina E, Keller L, Skrzeczkowska Z, Wang Q, Lei HC, Khasanov R, Amato A, Jia S, Neupert T, Luetkens H, Hasan MZ. Tunable anomalous Hall conductivity through volume-wise magnetic competition in a topological kagome magnet. Nat Commun 2020; 11:559. [PMID: 31992705 PMCID: PMC6987130 DOI: 10.1038/s41467-020-14325-w] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 12/17/2019] [Indexed: 11/23/2022] Open
Abstract
Magnetic topological phases of quantum matter are an emerging frontier in physics and material science. Along these lines, several kagome magnets have appeared as the most promising platforms. Here, we explore magnetic correlations in the kagome magnet Co3Sn2S2. Using muon spin-rotation, we present evidence for competing magnetic orders in the kagome lattice of this compound. Our results show that while the sample exhibits an out-of-plane ferromagnetic ground state, an in-plane antiferromagnetic state appears at temperatures above 90 K, eventually attaining a volume fraction of 80% around 170 K, before reaching a non-magnetic state. Strikingly, the reduction of the anomalous Hall conductivity (AHC) above 90 K linearly follows the disappearance of the volume fraction of the ferromagnetic state. We further show that the competition of these magnetic phases is tunable through applying either an external magnetic field or hydrostatic pressure. Our results taken together suggest the thermal and quantum tuning of Berry curvature induced AHC via external tuning of magnetic order.
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Affiliation(s)
- Z Guguchia
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland.
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
| | - J A T Verezhak
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - D J Gawryluk
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - S S Tsirkin
- Department of Physics, University of Zürich, Winterthurerstrasse 190, Zurich, Switzerland
| | - J-X Yin
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - I Belopolski
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - H Zhou
- International Center for Quantum Materials and School of Physics, Peking University, Beijing, China
- CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Science, Beijing, China
| | - G Simutis
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - S-S Zhang
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - T A Cochran
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - G Chang
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA
| | - E Pomjakushina
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - L Keller
- Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232, Villigen PSI, Switzerland
| | - Z Skrzeczkowska
- Laboratory for Multiscale Materials Experiments, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - Q Wang
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing, China
| | - H C Lei
- Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices, Renmin University of China, Beijing, China
| | - R Khasanov
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - A Amato
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland
| | - S Jia
- International Center for Quantum Materials and School of Physics, Peking University, Beijing, China
- CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Science, Beijing, China
| | - T Neupert
- Department of Physics, University of Zürich, Winterthurerstrasse 190, Zurich, Switzerland
| | - H Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen PSI, Switzerland.
| | - M Z Hasan
- Laboratory for Topological Quantum Matter and Spectroscopy, Department of Physics, Princeton University, Princeton, NJ, 08544, USA.
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16
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Puphal P, Pomjakushin V, Kanazawa N, Ukleev V, Gawryluk DJ, Ma J, Naamneh M, Plumb NC, Keller L, Cubitt R, Pomjakushina E, White JS. Topological Magnetic Phase in the Candidate Weyl Semimetal CeAlGe. Phys Rev Lett 2020; 124:017202. [PMID: 31976692 DOI: 10.1103/physrevlett.124.017202] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 11/01/2019] [Indexed: 06/10/2023]
Abstract
We report the discovery of topological magnetism in the candidate magnetic Weyl semimetal CeAlGe. Using neutron scattering we find this system to host several incommensurate, square-coordinated multi-k[over →] magnetic phases below T_{N}. The topological properties of a phase stable at intermediate magnetic fields parallel to the c axis are suggested by observation of a topological Hall effect. Our findings highlight CeAlGe as an exceptional system for exploiting the interplay between the nontrivial topologies of the magnetization in real space and Weyl nodes in momentum space.
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Affiliation(s)
- Pascal Puphal
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Vladimir Pomjakushin
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Naoya Kanazawa
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
| | - Victor Ukleev
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Dariusz J Gawryluk
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Junzhang Ma
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - Muntaser Naamneh
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - Nicholas C Plumb
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - Lukas Keller
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Robert Cubitt
- Institut Laue-Langevin (ILL), 71 avenue des Martyrs, CS 20156, 38042 Grenoble cedex 9, France
| | - Ekaterina Pomjakushina
- Laboratory for Multiscale Materials Experiments (LMX), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
| | - Jonathan S White
- Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), CH-5232 Villigen, Switzerland
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17
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Holzamer A, Kim WK, Rück A, Sathananthan J, Keller L, Cosma J, Bauer T, Nef H, Amat-Santos IJ, Brinkert M, Husser O, Pellegrini C, Schofer J, Nerla R, Montorfano M, Giannini F, Stella P, Kuwata S, Hilker M, Castriota F, Ussia GP, Webb JG, Nietlispach F, Toggweiler S. Valve-in-Valve Implantation Using the ACURATE Neo in Degenerated Aortic Bioprostheses. JACC Cardiovasc Interv 2019; 12:2309-2316. [DOI: 10.1016/j.jcin.2019.07.042] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/26/2019] [Accepted: 07/23/2019] [Indexed: 12/21/2022]
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18
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Puphal P, Pomjakushin V, Gawryluk D, Keller L, Pomjakushina E, White JS. Superspace magnetic structure and topological charges in Weyl semimetal CeAlGe. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319091642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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19
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Maity SR, Ceretti M, Keller L, Schefer J, Shang T, Pomjakushina E, Meven M, Sheptyakov D, Cervellino A, Paulus W. Structural disorder and magnetic correlations driven by oxygen doping in Nd 2NiO 4.11. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319091630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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20
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Pouypoudat L, Vinatier D, Keller L, Decanter C, Leroy-Martin B, Piver P, Collinet P. [Autotransplantation of cryoconserved ovarian tissue: First experience in Universitary Hospital Center of Lille]. ACTA ACUST UNITED AC 2019; 47:704-705. [PMID: 31401232 DOI: 10.1016/j.gofs.2019.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Indexed: 11/18/2022]
Affiliation(s)
- L Pouypoudat
- Service d'obstétrique et de médecine fœtale, maternité universitaire, CHRU de Nancy, 54000 Nancy, France.
| | - D Vinatier
- Pôle femme-mère-enfant, université de Lille, avenue Eugène-Avinée, 59000 Lille, France; EA 2694, pôle recherche aile est 2(e) étage, épidémiologie et qualité des soins, université de Lille, 59045 Lille cedex, France
| | - L Keller
- Pôle femme-mère-enfant, université de Lille, avenue Eugène-Avinée, 59000 Lille, France
| | - C Decanter
- Pôle femme-mère-enfant, université de Lille, avenue Eugène-Avinée, 59000 Lille, France
| | - B Leroy-Martin
- Pôle femme-mère-enfant, université de Lille, avenue Eugène-Avinée, 59000 Lille, France
| | - P Piver
- CHU de Limoges, hôpital de la mère et de l'enfant, 8, avenue Dominique-Larrey, 87000 Limoges, France
| | - P Collinet
- Pôle femme-mère-enfant, université de Lille, avenue Eugène-Avinée, 59000 Lille, France; EA 2694, pôle recherche aile est 2(e) étage, épidémiologie et qualité des soins, université de Lille, 59045 Lille cedex, France
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21
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Keller L, Huth M. Pattern generation for direct-write three-dimensional nanoscale structures via focused electron beam induced deposition. Beilstein J Nanotechnol 2018; 9:2581-2598. [PMID: 30345218 PMCID: PMC6176821 DOI: 10.3762/bjnano.9.240] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 08/28/2018] [Indexed: 05/30/2023]
Abstract
Fabrication of three-dimensional (3D) nanoarchitectures by focused electron beam induced deposition (FEBID) has matured to a level that highly complex and functional deposits are becoming available for nanomagnetics and plasmonics. However, the generation of suitable pattern files that control the electron beam's movement, and thereby reliably map the desired target 3D structure from a purely geometrical description to a shape-conforming 3D deposit, is nontrivial. To address this issue we developed several writing strategies and associated algorithms implemented in C++. Our pattern file generator handles different proximity effects and corrects for height-dependent precursor coverage. Several examples of successful 3D nanoarchitectures using different precursors are presented that validate the effectiveness of the implementation.
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Affiliation(s)
- Lukas Keller
- Institute of Physics, Goethe University, Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
| | - Michael Huth
- Institute of Physics, Goethe University, Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany
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22
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Smith G, Yan L, Ren Y, Keller L, Yan Z, Qiao J. Towards understanding human embryo mosaicism: regional and developmental genetic concordance by single cell sequencing. Fertil Steril 2018. [DOI: 10.1016/j.fertnstert.2018.07.316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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23
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Maity SR, Keller L, Schefer J, Ceretti M, Paulus W. Neutron diffraction studies of oxygen disorder in Nd 2NiO 4+d
. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s2053273318094160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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24
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Schefer J, Birk J, Holm SL, Mannix D, Iversen K, Kolevatov R, Hauback B, Lefmann K, Keller L, Christensen M. HEIMDAL@ESS – fast neutron powder diffraction for materials science. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s2053273318088964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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25
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Li F, Pomjakushin V, Sibille R, Yadav R, Keller L, Medarde M, Conder K, Pomjakushina E. Revisiting the magnetic structure of La 1/3Sr 2/3FeO 3 by neutron powder diffraction. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s2053273318093701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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26
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Giblin SR, Twengström M, Bovo L, Ruminy M, Bartkowiak M, Manuel P, Andresen JC, Prabhakaran D, Balakrishnan G, Pomjakushina E, Paulsen C, Lhotel E, Keller L, Frontzek M, Capelli SC, Zaharko O, McClarty PA, Bramwell ST, Henelius P, Fennell T. Pauling Entropy, Metastability, and Equilibrium in Dy_{2}Ti_{2}O_{7} Spin Ice. Phys Rev Lett 2018; 121:067202. [PMID: 30141658 DOI: 10.1103/physrevlett.121.067202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Indexed: 06/08/2023]
Abstract
Determining the fate of the Pauling entropy in the classical spin ice material Dy_{2}Ti_{2}O_{7} with respect to the third law of thermodynamics has become an important test case for understanding the existence and stability of ice-rule states in general. The standard model of spin ice-the dipolar spin ice model-predicts an ordering transition at T≈0.15 K, but recent experiments by Pomaranski et al. suggest an entropy recovery over long timescales at temperatures as high as 0.5 K, much too high to be compatible with the theory. Using neutron scattering and specific heat measurements at low temperatures and with long timescales (0.35 K/10^{6} s and 0.5 K/10^{5} s, respectively) on several isotopically enriched samples, we find no evidence of a reduction of ice-rule correlations or spin entropy. High-resolution simulations of the neutron structure factor show that the spin correlations remain well described by the dipolar spin ice model at all temperatures. Furthermore, by careful consideration of hyperfine contributions, we conclude that the original entropy measurements of Ramirez et al. are, after all, essentially correct: The short-time relaxation method used in that study gives a reasonably accurate estimate of the equilibrium spin ice entropy due to a cancellation of contributions.
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Affiliation(s)
- S R Giblin
- School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, United Kingdom
| | - M Twengström
- Department of Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | - L Bovo
- London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, 17-19 Gordon Street, London, WC1H OAH, United Kingdom
- Department of Innovation and Enterprise, University College London, 90 Tottenham Court Road, Fitzrovia, London W1T 4TJ, United Kingdom
| | - M Ruminy
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Bartkowiak
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - P Manuel
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, United Kingdom
| | - J C Andresen
- Department of Physics, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| | - D Prabhakaran
- Clarendon Laboratory, Physics Department, Oxford University, Oxford, OX1 3PU, United Kingdom
| | - G Balakrishnan
- Department of Physics, University of Warwick, Coventry, CV4 7AL, United Kingdom
| | - E Pomjakushina
- Laboratory for Scientific Developments, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - C Paulsen
- Institut Néel, C.N.R.S-Université Joseph Fourier, B.P. 166, 38042 Grenoble, France
| | - E Lhotel
- Institut Néel, C.N.R.S-Université Joseph Fourier, B.P. 166, 38042 Grenoble, France
| | - L Keller
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - M Frontzek
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - S C Capelli
- ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, United Kingdom
| | - O Zaharko
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - P A McClarty
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, 01187 Dresden, Germany
| | - S T Bramwell
- London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, 17-19 Gordon Street, London, WC1H OAH, United Kingdom
| | - P Henelius
- Department of Physics, Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | - T Fennell
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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27
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Strub M, Keller L, Idoux-Gillet Y, Lesot H, Clauss F, Benkirane-Jessel N, Kuchler-Bopp S. Bone Marrow Stromal Cells Promote Innervation of Bioengineered Teeth. J Dent Res 2018; 97:1152-1159. [PMID: 29879365 DOI: 10.1177/0022034518779077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Transplantation of bone marrow mesenchymal stem cells (BMDCs) into a denervated side of the spinal cord was reported to be a useful option for axonal regeneration. The innervation of teeth is essential for their function and protection but does not occur spontaneously after injury. Cultured reassociations between dissociated embryonic dental mesenchymal and epithelial cells and implantation lead to a vascularized tooth organ regeneration. However, when reassociations were coimplanted with a trigeminal ganglion (TG), innervation did not occur. On the other hand, reassociations between mixed embryonic dental mesenchymal cells and bone marrow-derived cells isolated from green fluorescent protein (GFP) transgenic mice (BMDCs-GFP) (50/50) with an intact and competent dental epithelium (ED14) were innervated. In the present study, we verified the stemness of isolated BMDCs, confirmed their potential role in the innervation of bioengineered teeth, and analyzed the mechanisms by which this innervation can occur. For that purpose, reassociations between mixed embryonic dental mesenchymal cells and BMDCs-GFP with an intact and competent dental epithelium were cultured and coimplanted subcutaneously with a TG for 2 wk in ICR mice. Axons entered the dental pulp and reached the odontoblast layer. BMDCs-GFP were detected at the base of the tooth, with some being present in the pulp associated with the axons. Thus, while having a very limited contribution in tooth formation, they promoted the innervation of the bioengineered teeth. Using quantitative reverse transcription polymerase chain reaction and immunostainings, BMDCs were shown to promote innervation by 2 mechanisms: 1) via immunomodulation by reducing the number of T lymphocytes (CD3+, CD25+) in the implants and 2) by expressing neurotrophic factors such as NGF, BDNF, and NT3 for axonal growth. This strategy using autologous mesenchymal cells coming from bone marrow could be used to innervate bioengineered teeth without treatment with an immunosuppressor such as cyclosporine A (CsA), thus avoiding multiple side effects.
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Affiliation(s)
- M Strub
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France.,2 Université de Strasbourg (UDS), Faculté de Chirurgie Dentaire, Strasbourg, France.,3 Hôpitaux Universitaires de Strasbourg (HUS), Department of Pediatric Dentistry, Strasbourg, France
| | - L Keller
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France.,2 Université de Strasbourg (UDS), Faculté de Chirurgie Dentaire, Strasbourg, France
| | - Y Idoux-Gillet
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France.,2 Université de Strasbourg (UDS), Faculté de Chirurgie Dentaire, Strasbourg, France
| | - H Lesot
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France
| | - F Clauss
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France.,2 Université de Strasbourg (UDS), Faculté de Chirurgie Dentaire, Strasbourg, France.,3 Hôpitaux Universitaires de Strasbourg (HUS), Department of Pediatric Dentistry, Strasbourg, France
| | - N Benkirane-Jessel
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France.,2 Université de Strasbourg (UDS), Faculté de Chirurgie Dentaire, Strasbourg, France
| | - S Kuchler-Bopp
- 1 INSERM (French National Institute of Health and Medical Research), Regenerative NanoMedicine (RNM), FMTS, Strasbourg, France
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28
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Brambilla A, Keller L, Bassano B, Grossen C. Heterozygosity-fitness correlation at the major histocompatibility complex despite low variation in Alpine ibex ( Capra ibex). Evol Appl 2018; 11:631-644. [PMID: 29875807 PMCID: PMC5979623 DOI: 10.1111/eva.12575] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 10/30/2017] [Indexed: 01/06/2023] Open
Abstract
Crucial for the long-term survival of wild populations is their ability to fight diseases. Disease outbreaks can lead to severe population size reductions, which makes endangered and reintroduced species especially vulnerable. In vertebrates, the major histocompatibility complex (MHC) plays an important role in determining the immune response. Species that went through severe bottlenecks often show very low levels of genetic diversity at the MHC. Due to the known link between the MHC and immune response, such species are expected to be at particular risk in case of disease outbreaks. However, so far, only few studies have shown that low MHC diversity is correlated with increased disease susceptibility in species after severe bottlenecks. We investigated genetic variation at the MHC and its correlations with disease resistance and other fitness-related traits in Alpine ibex (Capra ibex), a wild goat species that underwent a strong bottleneck in the last century and that is known to have extremely low genetic variability, both genome-wide and at the MHC. We studied MHC variation in male ibex of Gran Paradiso National Park, the population used as a source for all postbottleneck reintroductions. We found that individual MHC heterozygosity (based on six microsatellites) was not correlated with genome-wide neutral heterozygosity. MHC heterozygosity, but not genome-wide heterozygosity, was positively correlated with resistance to infectious keratoconjunctivitis and with body mass. Our results show that genetic variation at the MHC plays an important role in disease resistance and, hence, should be taken into account for successfully managing species conservation.
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Affiliation(s)
- Alice Brambilla
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurich (ZH)Switzerland
- Alpine Wildlife Research CentreGran Paradiso National ParkNoasca (TO)Italy
| | - Lukas Keller
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurich (ZH)Switzerland
| | - Bruno Bassano
- Alpine Wildlife Research CentreGran Paradiso National ParkNoasca (TO)Italy
| | - Christine Grossen
- Department of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurich (ZH)Switzerland
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Kubus M, Lanza A, Scatena R, Dos Santos LHR, Wehinger B, Casati N, Fiolka C, Keller L, Macchi P, Rüegg C, Krämer KW. Quasi-2D Heisenberg Antiferromagnets [CuX(pyz) 2](BF 4) with X = Cl and Br. Inorg Chem 2018; 57:4934-4943. [PMID: 29389126 DOI: 10.1021/acs.inorgchem.7b03150] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two Cu2+ coordination polymers [CuCl(pyz)2](BF4) 1 and [CuBr(pyz)2](BF4) 2 (pyz = pyrazine) were synthesized in the family of quasi two-dimensional (2D) [Cu(pyz)2]2+ magnetic networks. The layer connectivity by monatomic halide ligands results in significantly shorter interlayer distances. Structures were determined by single-crystal X-ray diffraction. Temperature-dependent X-ray diffraction of 1 revealed rigid [Cu(pyz)2]2+ layers that do not expand between 5 K and room temperature, whereas the expansion along the c-axis amounts to 2%. The magnetic susceptibility of 1 and 2 shows a broad maximum at ∼8 K, indicating antiferromagnetic interactions within the [Cu(pyz)2]2+ layers. 2D Heisenberg model fits result in J∥ = 9.4(1) K for 1 and 8.9(1) K for 2. The interlayer coupling is much weaker with | J⊥| = 0.31(6) K for 1 and 0.52(9) K for 2. The electron density, experimentally determined and calculated by density functional theory, confirms the location of the singly occupied orbital (the magnetic orbital) in the tetragonal plane. The analysis of the spin density reveals a mainly σ-type exchange through pyrazine. Kinks in the magnetic susceptibility indicate the onset of long-range three-dimensional magnetic order below 4 K. The magnetic structures were determined by neutron diffraction. Magnetic Bragg peaks occur below TN = 3.9(1) K for 1 and 3.8(1) K for 2. The magnetic unit cell is doubled along the c-axis ( k = 0, 0, 0.5). The ordered magnetic moments are located in the tetragonal plane and amount to 0.76(8) μB/Cu2+ for 1 and 0.6(1) μB/Cu2+ for 2 at 1.5 K. The moments are coupled antiferromagnetically both in the ab plane and along the c-axis. The Cu2+ g-tensor was determined from electron spin resonance spectra as g x = 2.060(1), g z = 2.275(1) for 1 and g x = 2.057(1), g z = 2.272(1) for 2 at room temperature.
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Affiliation(s)
- Mariusz Kubus
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
| | - Arianna Lanza
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
| | - Rebecca Scatena
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
| | - Leonardo H R Dos Santos
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
| | - Björn Wehinger
- Department of Quantum Matter Physics , University of Geneva , Quai Ernest Ansermet 24 , CH-1211 Genève 4 , Switzerland
| | | | - Christoph Fiolka
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
| | | | - Piero Macchi
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
| | - Christian Rüegg
- Department of Quantum Matter Physics , University of Geneva , Quai Ernest Ansermet 24 , CH-1211 Genève 4 , Switzerland
| | - Karl W Krämer
- Department of Chemistry and Biochemistry , University of Bern , Freiestrasse 3 , CH-3012 Bern , Switzerland
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Gao S, Zaharko O, Tsurkan V, Prodan L, Riordan E, Lago J, Fåk B, Wildes AR, Koza MM, Ritter C, Fouquet P, Keller L, Canévet E, Medarde M, Blomgren J, Johansson C, Giblin SR, Vrtnik S, Luzar J, Loidl A, Rüegg C, Fennell T. Dipolar Spin Ice States with a Fast Monopole Hopping Rate in CdEr_{2}X_{4} (X=Se, S). Phys Rev Lett 2018; 120:137201. [PMID: 29694199 DOI: 10.1103/physrevlett.120.137201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Indexed: 06/08/2023]
Abstract
Excitations in a spin ice behave as magnetic monopoles, and their population and mobility control the dynamics of a spin ice at low temperature. CdEr_{2}Se_{4} is reported to have the Pauling entropy characteristic of a spin ice, but its dynamics are three orders of magnitude faster than the canonical spin ice Dy_{2}Ti_{2}O_{7}. In this Letter we use diffuse neutron scattering to show that both CdEr_{2}Se_{4} and CdEr_{2}S_{4} support a dipolar spin ice state-the host phase for a Coulomb gas of emergent magnetic monopoles. These Coulomb gases have similar parameters to those in Dy_{2}Ti_{2}O_{7}, i.e., dilute and uncorrelated, and so cannot provide three orders faster dynamics through a larger monopole population alone. We investigate the monopole dynamics using ac susceptometry and neutron spin echo spectroscopy, and verify the crystal electric field Hamiltonian of the Er^{3+} ions using inelastic neutron scattering. A quantitative calculation of the monopole hopping rate using our Coulomb gas and crystal electric field parameters shows that the fast dynamics in CdEr_{2}X_{4} (X=Se, S) are primarily due to much faster monopole hopping. Our work suggests that CdEr_{2}X_{4} offer the possibility to study alternative spin ice ground states and dynamics, with equilibration possible at much lower temperatures than the rare earth pyrochlore examples.
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Affiliation(s)
- Shang Gao
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Department of Quantum Matter Physics, University of Geneva, CH-1211 Geneva, Switzerland
| | - O Zaharko
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - V Tsurkan
- Experimental Physics V, University of Augsburg, D-86135 Augsburg, Germany
- Institute of Applied Physics, Academy of Sciences of Moldova, MD-2028 Chisinau, Republic of Moldova
| | - L Prodan
- Institute of Applied Physics, Academy of Sciences of Moldova, MD-2028 Chisinau, Republic of Moldova
| | - E Riordan
- School of Physics and Astronomy, Cardiff University, CF24 3AA Cardiff, United Kingdom
| | - J Lago
- Department of Inorganic Chemistry, Universidad del País Vasco (UPV-EHU), 48080 Bilbao, Spain
| | - B Fåk
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - A R Wildes
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - M M Koza
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - C Ritter
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - P Fouquet
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - L Keller
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - E Canévet
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Department of Physics, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - M Medarde
- Laboratory for Scientific Developments and Novel Materials, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - J Blomgren
- RISE Acreo AB, SE-411 33 Göteborg, Sweden
| | | | - S R Giblin
- School of Physics and Astronomy, Cardiff University, CF24 3AA Cardiff, United Kingdom
| | - S Vrtnik
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - J Luzar
- Jožef Stefan Institute, SI-1000 Ljubljana, Slovenia
| | - A Loidl
- Experimental Physics V, University of Augsburg, D-86135 Augsburg, Germany
| | - Ch Rüegg
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
- Department of Quantum Matter Physics, University of Geneva, CH-1211 Geneva, Switzerland
| | - T Fennell
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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Al Mamoori MKI, Keller L, Pieper J, Barth S, Winkler R, Plank H, Müller J, Huth M. Magnetic Characterization of Direct-Write Free-Form Building Blocks for Artificial Magnetic 3D Lattices. Materials (Basel) 2018; 11:E289. [PMID: 29439553 PMCID: PMC5848986 DOI: 10.3390/ma11020289] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/07/2018] [Accepted: 02/07/2018] [Indexed: 11/16/2022]
Abstract
Three-dimensional (3D) nanomagnetism, where spin configurations extend into the vertical direction of a substrate plane allow for more complex, hierarchical systems and the design of novel magnetic effects. As an important step towards this goal, we have recently demonstrated the direct-write fabrication of freestanding ferromagnetic 3D nano-architectures of ferromagnetic CoFe in shapes of nano-tree and nano-cube structures by means of focused electron beam induced deposition. Here, we present a comprehensive characterization of the magnetic properties of these structures by local stray-field measurements using a high-resolution micro-Hall magnetometer. Measurements in a wide range of temperatures and different angles of the externally applied magnetic field with respect to the surface plane of the sensor are supported by corresponding micromagnetic simulations, which explain the overall switching behavior of in part rather complex magnetization configurations remarkably well. In particular, the simulations yield coercive and switching fields that are in good quantitative correspondence with the measured coercive and switching fields assuming a bulk metal content of 100 at % consisting of bcc Co 3 Fe. We show that thermally-unstable magnetization states can be repetitively prepared and their lifetime controlled at will, a prerequisite to realizing dynamic and thermally-active magnetic configurations if the building blocks are to be used in lattice structures.
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Affiliation(s)
| | - Lukas Keller
- Institute of Physics, Goethe University, 60438 (M) Frankfurt, Germany.
| | - Jonathan Pieper
- Institute of Physics, Goethe University, 60438 (M) Frankfurt, Germany.
| | - Sven Barth
- Institute of Materials Chemistry, Vienna University of Technology, 1060 Vienna, Austria.
| | - Robert Winkler
- Graz Centre for Electron Microscopy, 8010 Graz, Austria.
| | - Harald Plank
- Institute of Electron Microscopy and Nanoanalysis, Graz University of Technology, 8010 Graz, Austria.
| | - Jens Müller
- Institute of Physics, Goethe University, 60438 (M) Frankfurt, Germany.
| | - Michael Huth
- Institute of Physics, Goethe University, 60438 (M) Frankfurt, Germany.
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Keller L, Meichner K, Unterer S, Hartmann K, Zenker I. Immune mediated destruction of platelets in dogs with heat stroke: A prospective study. Tierarztl Prax Ausg K 2018. [DOI: 10.1055/s-0038-1622811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Summary
Objective: Severe thrombocytopenia is a common sequelae to heat stroke in dogs. So far it has been hypothezised that it is due to disseminated intravascular coagulation. We hypothezised that it is due to immune mediated destruction via antiplatelet antibodies. Material and methods: Prospective evaluation of dogs with heat stroke from May 2005 to August 2008. Dogs that developed severe thrombocytopenia within 5 days of admission were included in the study. All dogs were treated with a standardized treatment protocol. In addition, they received either immunoglobulins or prednisolone. Results: Six dogs were presented with heat stroke during that time period. Four developed a severe thrombocytopenia. All four dogs tested positive for antiplatelet antibodies and did not have elevated D-Dimers at that time. Platelet count in three dogs recovered fully, one dog was euthanized due to liver and renal failure. Conclusion: In those cases thrombocytopenia was due to immune mediated destruction not due to DIC. Clinical rele-vance: Due to the severity of the thrombocytopenia and the high risk for bleeding in those patients, immunosuppressive therapy in addition to DIC prophylaxis should be discussed.
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Abstract
Zusammenfassung:
Gegenstand und Ziel: Der Fallbericht erörtert das diagnostische Vorgehen und differenzialdiagnostische Überlegungen bei Patienten mit Mikrofilarämie und negativem Dirofilaria-immitis-Antigentest und diskutiert die Infektion mit Dirofilaria repens und deren Therapie. Material und Methode: Bei einem Hund aus Ungarn wurden im Blutausstrich Mikrofilarien gefunden. Die weitere Diagnostik zur Differenzierung der Mikrofilarien umfasste einen Dirofilaria-immitis-Antigentest, eine Polymerasekettenreaktion zum Nachweis von Dirofilaria immitis und Dipetalonema reconditum sowie eine Saure-Phosphatase-Reaktion zur Diagnose einer Infektion mit Dirofilaria repens. Ergebnisse: Mittels der Saure-Phosphatase-Reaktion konnte eine Infektion mit Dirofilaria repens diagnostiziert werden. Die Therapie gegen die Mikrofilarien erfolgte mit Selamectin. Schlussfolgerung und klinische Relevanz: Bei mikrofilarämischen Patienten muss differenzialdiagnostisch neben einer Infektion mit Dirofilaria immitis eine Infektion mit anderen, weniger pathogenen Parasiten in Betracht gezogen werden, da sich die Notwendigkeit einer Therapie und das Therapieregime je nach Infektion deutlich unterscheiden.
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Maity SR, Schefer J, Keller L, Ceretti M, Paulus W. Neutron diffraction studies of oxygen disorder in Nd 2NiO 4+d
. Acta Crystallogr A Found Adv 2017. [DOI: 10.1107/s2053273317081505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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35
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Keller L, Meyer N, Pradines A, Casanova A, Farella M, Brayer S, Favre G, Filleron T. L’évaluation précoce de la variation du ctDNA est un facteur prédictif de rechute des patients traités par immunothérapie. Ann Dermatol Venereol 2017. [DOI: 10.1016/j.annder.2017.09.535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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36
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Reis C, Pilz LK, Keller L, Roenneberg T, Paiva T. PSQI largely ignores sleep on work-free days both in the general population and in clinical sleep medicine samples. Sleep Med 2017. [DOI: 10.1016/j.sleep.2017.11.812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Piskorz D, Bongarzoni L, Citta L, Citta N, Citta P, Keller L, Mata L, Tommasi A. World Health Organization cardiovascular risk stratification and target organ damage. Hipertens Riesgo Vasc 2017; 33:14-20. [PMID: 26521088 DOI: 10.1016/j.hipert.2015.09.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/19/2015] [Accepted: 09/09/2015] [Indexed: 12/28/2022]
Abstract
BACKGROUND Prediction charts allow treatment to be targeted according to simple markers of cardiovascular risk; many algorithms do not recommend screening asymptomatic target organ damage which could change dramatically the assessment. OBJECTIVE To demonstrate that target organ damage is present in low cardiovascular risk hypertensive patients and it is more frequent and severe as global cardiovascular risk increases. METHODS Consecutive hypertensive patients treated at a single Latin American center. Cardiovascular risk stratified according to 2013 WHO/ISH risk prediction chart America B. Left ventricular mass assessed by Devereux method, left ventricular hypertrophy considered >95g/m(2) in women and >115g/m(2) in men. Transmitral diastolic peak early flow velocity to average septal/lateral peak early diastolic relaxation velocity (E/e' ratio) measured cut off value >13. Systolic function assessed by tissue Doppler average interventricular septum/lateral wall mitral annulus rate systolic excursion (s wave). RESULTS A total of 292 patients were included of whom 159 patients (54.5%) had cardiovascular risk of <10%, 90 (30.8%) had cardiovascular risk of 10-20% and 43 (14.7%) had cardiovascular risk of >20%. Left ventricular hypertrophy was detected in 17.6% low risk patients, 27.8% in medium risk and 23.3% in high risk (p<0.05), abnormal E/e' ratio was found in 13.8%, 31.1% and 27.9%, respectively (p<0.05). Mean s wave was 8.03+8, 8.1+9 and 8.7+1cm/s for low, intermediate and high risk patients, respectively (p<0.025). CONCLUSIONS Target organ damage is more frequent and severe in high risk; one over four subjects was misclassified due to the presence of asymptomatic target organ damage.
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Affiliation(s)
- D Piskorz
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina; Centro de Investigaciones Cardiovasculares, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina.
| | - L Bongarzoni
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
| | - L Citta
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
| | - N Citta
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
| | - P Citta
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
| | - L Keller
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
| | - L Mata
- Instituto de Cardiología, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
| | - A Tommasi
- Centro de Investigaciones Cardiovasculares, Sanatorio Británico SA, Paraguay 40, 2000 Rosario, Argentina
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38
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Smith G, Parker W, Keller L, Li Y, Brady A, Leibo S. Human semen parameters that predict sperm dna integrity after cryopreservation. Fertil Steril 2017. [DOI: 10.1016/j.fertnstert.2017.07.528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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39
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Keller L, Regiel-Futyra A, Gimeno M, Eap S, Mendoza G, Andreu V, Wagner Q, Kyzioł A, Sebastian V, Stochel G, Arruebo M, Benkirane-Jessel N. Chitosan-based nanocomposites for the repair of bone defects. Nanomedicine 2017. [PMID: 28647591 DOI: 10.1016/j.nano.2017.06.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Chitosan scaffolds of different deacetylation degrees, average molecular weights and concentrations reinforced with silica nanoparticles were prepared for bone tissue regeneration. The resulting nanocomposites showed similar pore sizes (<300 μm) regardless the deacetylation degree and concentration used in their formulation. Their mechanical compression resistance was increased by a 30% with the addition of silica nanoparticles as nanofillers. The biocompatibility of the three-dimensional chitosan scaffolds was confirmed by the Alamar Blue assay in human primary osteoblasts as well as the formation of cell spheroids indicative of their great potential for bone regeneration. In vivo implantation of the scaffolds in a mice calvaria defect model provided substantial evidences of the suitability of these nanocomposites for bone tissue engineering showing a mature and dense collagenous tissue with small foci of mineralization, vascularized areas and the infiltration of osteoblasts and osteoclasts. Nevertheless, mature bone tissue formation was not observed after eight weeks of implantation.
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Affiliation(s)
- L Keller
- INSERM, Unité Mixte de Recherche UMR 1109, Team "Osteoarticular and Dental Regenerative NanoMedicine," Fédération de Médecine Translationnelle de Strasbourg, Faculté de Chirurgie Dentaire, UDS, Strasbourg, France
| | - A Regiel-Futyra
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland
| | - M Gimeno
- Faculty of Veterinary, Department of Animal Pathology, University of Zaragoza, Spain
| | - S Eap
- INSERM, Unité Mixte de Recherche UMR 1109, Team "Osteoarticular and Dental Regenerative NanoMedicine," Fédération de Médecine Translationnelle de Strasbourg, Faculté de Chirurgie Dentaire, UDS, Strasbourg, France
| | - G Mendoza
- Department of Chemical Engineering, Aragon Institute of Nanoscience (INA), University of Zaragoza, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain; Aragon Health Research Institute (IIS Aragón), 50009, Zaragoza, Spain.
| | - V Andreu
- Department of Chemical Engineering, Aragon Institute of Nanoscience (INA), University of Zaragoza, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain; Aragon Health Research Institute (IIS Aragón), 50009, Zaragoza, Spain.
| | - Q Wagner
- INSERM, Unité Mixte de Recherche UMR 1109, Team "Osteoarticular and Dental Regenerative NanoMedicine," Fédération de Médecine Translationnelle de Strasbourg, Faculté de Chirurgie Dentaire, UDS, Strasbourg, France
| | - A Kyzioł
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland
| | - V Sebastian
- Department of Chemical Engineering, Aragon Institute of Nanoscience (INA), University of Zaragoza, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain; Aragon Health Research Institute (IIS Aragón), 50009, Zaragoza, Spain
| | - G Stochel
- Faculty of Chemistry, Jagiellonian University, Kraków, Poland
| | - M Arruebo
- Department of Chemical Engineering, Aragon Institute of Nanoscience (INA), University of Zaragoza, Zaragoza, Spain; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, CIBER-BBN, 28029, Madrid, Spain; Aragon Health Research Institute (IIS Aragón), 50009, Zaragoza, Spain
| | - N Benkirane-Jessel
- INSERM, Unité Mixte de Recherche UMR 1109, Team "Osteoarticular and Dental Regenerative NanoMedicine," Fédération de Médecine Translationnelle de Strasbourg, Faculté de Chirurgie Dentaire, UDS, Strasbourg, France
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Abstract
Collective foraging confers benefits in terms of reduced predation risk and access to social information, but it heightens local competition when resources are limited. In social insects, resource limitation has been suggested as a possible cause for the typical decrease in per capita productivity observed with increasing colony size, a phenomenon known as Michener's paradox. Polydomy (distribution of a colony's brood and workers across multiple nests) is believed to help circumvent this paradox through its positive effect on foraging efficiency, but there is still little supporting evidence for this hypothesis. Here, we show experimentally that polydomy enhances the foraging performance of food-deprived Temnothorax nylanderi ant colonies via several mechanisms. First, polydomy influences task allocation within colonies, resulting in faster retrieval of protein resources. Second, communication between sister nests reduces search times for far away resources. Third, colonies move queens, brood and workers across available nest sites in response to spatial heterogeneities in protein and carbohydrate resources. This suggests that polydomy represents a flexible mechanism for space occupancy, helping ant colonies adjust to the environment.
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Affiliation(s)
- N Stroeymeyt
- Department of Ecology and Evolution, Biophore, UNIL-Sorge, University of Lausanne, 1015 Lausanne, Switzerland
| | - P Joye
- Department of Ecology and Evolution, Biophore, UNIL-Sorge, University of Lausanne, 1015 Lausanne, Switzerland
| | - L Keller
- Department of Ecology and Evolution, Biophore, UNIL-Sorge, University of Lausanne, 1015 Lausanne, Switzerland
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Mailliez A, Keller L, Menu-Hespel S, Plouvier P, D'Orazio E, Basson L, Pigny P, Bonneterre J, Decanter C. Abstract P5-09-06: Ovarian reserve and response to controlled ovarian hyperstimulation (COH) in breast cancer women with and without BRCA mutation. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p5-09-06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: 6300 new cases of breast cancer arise in young women under 40 each year in France. Some of them are BRCA 1 or 2 mutation carriers. Most of them receive a potentially gonadotoxic chemotherapy while they have not yet completed their family. Since 2011, a systematic proposal of ovarian reserve follow-up and fertility preservation by oocyte freezing is provided to each young early breast cancer (BC) patients (pts) of our program (NCT 01614704). Preliminary results were presented at the SABCS in 2013. We now investigate the impact of BRCA mutation on the ovarian reserve and the ovarian response to simulation.
Methods: 115 young BC pts were systematically referred to a reproductive medicine centre before starting chemotherapy. Inclusion criteria were age 18 to 38, histologically confirmed invasive breast carcinoma, absence of metastases. According to their personal and familial history, genetic counselling was performed and if the patient met the criteria and agreed, BRCA genes were analysed. Pts in an adjuvant setting and who were asking for fertility preservation underwent COH during the interval between complete surgery and start of adjuvant chemotherapy. Ovarian stimulation protocol consisted in a conventional antagonist protocol with recombinant FSH starting on day 2 of the menstrual cycles. The GnRh antagonist was started on day of the COH and the final oocyte maturation was achieved by an injection of triptorelin 0.2 mg when at least 3 follicles reached 18 mm of diameter. All pts gave their informed consent for COH, egg/embryo freezing and follow-up.
Results: 115 pts achieved pre-treatment AMH and AFC assessment. 60 (52,1%) were eligible for COH in order to cryopreserve egg or embryos. BRCA analysis was performed in 83 pts. 23 did not meet the criteria or refused. 9 analyses are still in process. 17 (20.4%) pts were positive for BRCA mutation (BRCA1: 13; BRCA2: 4) and 66 were not. In the mutation carriers group (n=17), median age was 32 years (Range 25-37). Median initial AMH levels and AFC were 23 pmol/l (5.1–223) and 20 (6-100), respectively. Eight pts underwent COH. Median duration of stimulation was 9,5 days (8-13) with a median cumulative dose of gonadotropins of 2875 UI (1200-5450). The median number of vitrified oocytes was 5,5 (0-15). Two patients chose frozen embryo preservation (1 and 2 eggs respectively). In the non-carriers group (n=66), median age was 31 years (24-37). Median initial AMH levels and AFC were 23.4 pmol/l (0.8-136) and 24 (1-68). 27 pts underwent COH. Median duration of stimulation was 10 days (7-14). Dose of gonadotropins was 2700 UI (1365-5600). The median number of vitrified oocytes was 6 (0-18). The 3 patients chose eggs preservation (0.0 and 3 eggs respectively). There was no significant difference in the two groups.
Discussion/ Conclusion: Few studies stated that BRCA1 mutation may be associated with reduced ovarian reserve in healthy BRCA mutation carriers. Meirow and al concluded that both healthy and BC BRCA mutation carriers demonstrated normal ovarian response in vitro fertilization cycles. Our results show that ovarian reserve of BRCA 1/2 mutations BC carriers do not differ from that of non-carriers. Response to COH seems similar in both groups too.
Citation Format: Mailliez A, Keller L, Menu-Hespel S, Plouvier P, D'Orazio E, Basson L, Pigny P, Bonneterre J, Decanter C. Ovarian reserve and response to controlled ovarian hyperstimulation (COH) in breast cancer women with and without BRCA mutation [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-09-06.
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Affiliation(s)
- A Mailliez
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - L Keller
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - S Menu-Hespel
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - P Plouvier
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - E D'Orazio
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - L Basson
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - P Pigny
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - J Bonneterre
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
| | - C Decanter
- Centre Oscar Lambret, Lille, France; Hôpital Jeanne de Flandre, Lille, France; Centre de Biologie Pathotologie - CHRU, Lille, France
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Keller L, Regiel-Futyura A, Gimeno M, Eap S, Mendoza G, Andreu V, Wagner Q, Kyziol A, Arruebo M, Benkirane-Jessel N. Chitosan-Based Scaffold Integration in Mice Calvaria Defect Model: Histopathological Study. J Comp Pathol 2017. [DOI: 10.1016/j.jcpa.2016.11.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Hirschmann A, Schiapparelli FF, Schenk L, Keller L, Amsler F, Hirschmann MT. The Genovese grading scale is not reliable for MR assessment of collagen meniscus implants. Knee 2017; 24:9-15. [PMID: 27836691 DOI: 10.1016/j.knee.2016.10.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 10/15/2016] [Accepted: 10/19/2016] [Indexed: 02/02/2023]
Abstract
BACKGROUND The purpose of the study was to evaluate the intra- and inter-observer reliabilities of the Genovese grading on MRI in patients after collagen meniscus substitution. METHODS 84 MRI images of 74 consecutive patients who underwent partial meniscus substitution using collagen meniscus implant (CMI) were assessed. MRIs were evaluated using the Genovese grading system. Furthermore, meniscal extrusion was assessed. Two observers performed the grading twice, blinded to each other and to the previous results, with a six weeks interval. The inter- and intra-observer reliabilities were assessed using kappa and weighted kappa values. RESULTS The criterion "morphology/size" showed a weighted kappa value inter-observer reliability of 0.069 (rater 1)/0.352 (rater 2) and intra-observer reliability of 0.170 (1st rating)/0.582 (2nd rating). The criterion "signal intensity" showed a weighted kappa value inter-observer reliability of 0.175/0.284 and intra-observer reliability of 0.294/0.458. The criterion "cartilage lesions" showed a kappa value inter-observer reliability of 0.091/0.525 and intra-observer reliability of 0.409/0.413. The criterion "bone marrow edema" showed a kappa value inter-observer reliability of 0.667/0.808 and intra-observer reliability of 0.702/0.715. The criterion "cartilage lesions" showed a kappa value inter-observer reliability of 0.091/0.525 and intra-observer reliability of 0.409/0.413. Regarding meniscal extrusion kappa values for the inter-observer reliability were 0.625/0.940 and 0.625/0.889 for intra-observer reliability. CONCLUSIONS Three of the four Genovese grading items showed only slight to moderate inter- and intra-observer reliabilities in evaluating CMI on MRI. Hence, such grading results need to be considered with all due care. Only the criteria "bone marrow edema" and "meniscal extrusion" showed a good agreement for both inter- and intra-observer reliabilities.
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Affiliation(s)
- A Hirschmann
- Radiology and Nuclear Medicine, University Hospital Basel, Switzerland
| | - F F Schiapparelli
- Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), CH-4101 Bruderholz, Switzerland
| | - L Schenk
- Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), CH-4101 Bruderholz, Switzerland
| | - L Keller
- Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), CH-4101 Bruderholz, Switzerland
| | - F Amsler
- Amsler Consulting, Basel, Switzerland
| | - M T Hirschmann
- Department of Orthopaedic Surgery and Traumatology, Kantonsspital Baselland (Bruderholz, Liestal, Laufen), CH-4101 Bruderholz, Switzerland.
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Yaouanc A, Dalmas de Réotier P, Keller L, Roessli B, Forget A. A novel type of splayed ferromagnetic order observed in Yb2Ti2O7. J Phys Condens Matter 2016; 28:426002. [PMID: 27557664 DOI: 10.1088/0953-8984/28/42/426002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The pyrochlore insulator Yb2Ti2O7 has attracted the attention of experimentalists and theoreticians alike for about 15 years. Conflicting neutron diffraction data on the possible existence of magnetic Bragg reflections at low temperature have been published. Here we report the observation of magnetic Bragg reflections by neutron powder diffraction at 60 mK. The magnetic diffraction pattern is analyzed using representation theory. We find Yb2Ti2O7 to be a splayed ferromagnet as reported for Yb2Sn2O7, a sibling compound with also dominating ferromagnetic interactions as inferred from the positive Curie-Weiss temperature. However, the configuration of the magnetic moment components perpendicular to the easy axis is of the all-in-all-out type in Yb2Ti2O7 while it is two-in-two-out in the Yb2Sn2O7. An overall experimental picture of the magnetic properties emerges.
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Affiliation(s)
- A Yaouanc
- Université Grenoble Alpes, INAC-PHELIQS, F-38000 Grenoble, France. CEA, INAC-PHELIQS, F-38000 Grenoble, France
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Tissera G, Piskorz D, Citta L, Citta N, Citta P, Keller L, Bongarzoni L, Mata L, Tommasi A. Morphologic and Functional Heart Abnormalities Associated to High Modified Tei Index in Hypertensive Patients. High Blood Press Cardiovasc Prev 2016; 23:373-380. [PMID: 27623974 DOI: 10.1007/s40292-016-0167-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/05/2016] [Indexed: 01/20/2023] Open
Abstract
INTRODUCTION LV dysfunction develops early in hypertension, even previously to left ventricular remodeling. AIMS To determine the frequency of morphologic and functional heart abnormalities associated to abnormal modified Tei Index in untreated hypertensive (HBP) patients (p) with preserved ejection fraction (pEF). METHODS Case-control study. Three groups: (1) HBP without left ventricular hypertrophy (LVH); (2) HBP with LVH; (3) non-HBP controls. Ejection fraction >54 % identified pEF. LVH measured by Devereux method. Systolic and diastolic functions assessed by standard echocardiography and tissue Doppler. 2013 ESH/ESC Hypertension Guidelines normal values were considered. Tei index measured at the lateral and septal LV walls in apical 4-chamber view by tissue Doppler, value >0.40 considered abnormal. STATISTICAL ANALYSIS multifactorial ANOVA test adjusted by sex and age, p < 0.05 statistically significant. RESULTS The study included 14 controls, 88 HBP p without LVH, and 19 HBP p with LVH. The HBP p sample mean age was 58.7 ± 13.5 years and 52 (44.1 %) were males. Mean Tei Index was 0.35 ± 0.03 in controls; 0.42 ± 0.05 in HBP without LVH; and 0.42 ± 0.06 in HBP with LVH (p < 0.025). Abnormal Tei Index was present in 2p (14.3 %) controls; 64 p (72.7 %) HBP without LVH; and 15 p (78.9 %) HBP with LVH (p < 0.0009). Tissue Doppler's wave was 8.4 ± 0.9 cm/s in controls; 8 ± 1.6 cm/s in HBP without LVH and 7.8 ± 1.1 cm/s in HBP with LVH. CONCLUSIONS (1) Left ventricular dysfunction is frequent in HBP p, even without LVH; (2) modified tissue Doppler Tei index is a useful tool for the diagnosis of left ventricular dysfunction.
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Affiliation(s)
- G Tissera
- Centenario National Hospital, Urquiza 3000, 2000, Rosario, Argentina
| | - Daniel Piskorz
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina. .,Cardiovascular Research Center Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina.
| | - L Citta
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
| | - N Citta
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
| | - P Citta
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
| | - L Keller
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
| | - L Bongarzoni
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
| | - L Mata
- Cardiology Institute Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
| | - A Tommasi
- Cardiovascular Research Center Sanatorio Británico SA, Paraguay 40, 2000, Rosario, Argentina
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Keller L, Ohs B, Lenhart J, Wessling M. Hohlfasern aus Kohlenstoffnanoröhrchen mit immobilisiertem Polyethylenimin zur CO 2-Trennung. CHEM-ING-TECH 2016. [DOI: 10.1002/cite.201650258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lanza A, Scatena R, Santos LHRD, Kubus M, Krämer KW, Keller L, Fennell T, Wehinger B, Biffin A, Rüegg C, Casati N, Macchi P. Copper-pyrazine magnetic polymers under high pressure. Acta Crystallogr A Found Adv 2016. [DOI: 10.1107/s2053273316098697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Garbus PGR, Ahlburg J, Andersen HL, Keller L, Christensen M. In situ reduction of as-prepared γ-iron oxide nanoparticles. Acta Crystallogr A Found Adv 2016. [DOI: 10.1107/s2053273316095516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Mishra S, Schefer J, Keller L, Frontzek MD, Ceretti M, Paulus W. Interplay of structural complexity and magnetism in Pr 2NiO 4+δ single crystals. Acta Crystallogr A Found Adv 2016. [DOI: 10.1107/s2053273316095322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Rüegg C, Sibille R, Schefer J, Pomjakushin V, Sheptyakov D, Keller L, Canevet E, Panzner T, Zaharko O. News from the Swiss Spallation Neutron Source SINQ: diffraction at non-ambient conditions. Acta Crystallogr A Found Adv 2016. [DOI: 10.1107/s2053273316093918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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