The vital role of hole-carriers for superconductivity in pressurized black phosphorus

The influence of carrier type on superconductivity has been an important issue for understanding both conventional and unconventional superconductors [1-7]. For elements that superconduct, it is known that hole-carriers govern the superconductivity for transition and main group metals [8-10]. The role of hole-carriers in elements that are not normally conducting but can be converted to superconductors, however, remains unclear due to the lack of experimental data. Here we report the first in-situ high pressure Hall effect measurements on single crystal black phosphorus, measured up to ~ 50 GPa, and find a correlation between the Hall coefficient and the superconducting transition temperature (TC). Our results reveal that hole-carriers play a vital role in developing superconductivity and enhancing TC. Importantly, we also find a Lifshitz transition in the high-pressure cubic phase at ~17.2GPa, which uncovers the origin of a puzzling valley in the superconducting TC-pressure phase diagram. These results offer insight into the role of hole-carriers in developing superconductivity in simple semiconducting solids under pressure.Comment: 9 pages anf 3 figure

MicroRNA-1 and Circulating Microvesicles Mediate the Protective Effects of Dantonic in Acute Myocardial Infarction Rat Models

Aim: To investigate the protective effect of dantonic in ischemic myocardial damage by evaluating the expression of circulating microvesicles (MVs) and microRNA-1 (miR-1) in two animal models.Methods: Two animal models of myocardial ischemia were established that were isoproterenol-induced myocardial ischemia (ISO-AMI) rat model and the acute myocardial infarction rat model induced by ligation of the left anterior descending coronary artery (LAD-AMI) of rat. To investigate the protective effect of dantonic, we observed the myocardial infarction size, creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST) activities, cardiac troponin I (cTnI) level in serum, and the plasma levels of miR-1 and MVs.Results: The results showed that pretreatment with dantonic significantly attenuated the LAD-AMI induced myocardial damage by decreasing the size of myocardial infarction, CK, LDH, AST activities, and cTnI level in serum. High dose dantonic treatment could significantly abrogate the increased plasma levels of miR-1 and MVs as compared to the LAD rat model. In addition, pretreatment with dantonic also showed a significant myocardial protective effect through reducing the expression levels of CK, LDH, and AST as compared to the ISO-AMI model. Whereas the cTnI level was no significant difference between model group and control group, suggesting that the model caused less myocardial damage. In the ISO-induced myocardial ischemia model, there is no significant difference between the model group with the control group of MVs and miR-1 levels. This may be that miR-1 is reported as a biomarker of acute myocardial infarction. The pathological changes of IOS-induced acute myocardial ischemia model are also different from those of acute myocardial infarction.Conclusion: Dantonic showed the protective effect in these two ischemic myocardial injury rat models, whereas the circulating miR-1 and MVs levels were only ameliorated in the LAD rat model

Geodetic Constraints on the Crustal Deformation along the Kunlun Fault and Its Tectonic Implications

This study focuses on the crustal deformation and interseismic fault coupling along the strike-slip Kunlun fault, northern Tibet, whose western segment ruptured in the 2001 Mw 7.8 Kokoxili earthquake. We first integrated published Global Positioning System (GPS) velocity solutions and calculated strain rate fields covering the Kunlun fault. Our results show abnormally high post-earthquake strain rate values across the ruptures; furthermore, these exceed those in pre-earthquake data. Together with two tracks of interferometric synthetic aperture radar (InSAR) observations (2003–2010) and position time-series data from two continuous GPS sites, we show that the postseismic deformation of the Kokoxili earthquake may continue up to 2014; and that the postseismic transients of the earthquake affect the 2001–2014 GPS velocity solutions. We then processed the GPS data observed in 2014–2017 and obtained a dense interseismic velocity field for the northern Tibet. Using a fault dislocation model in a Bayesian framework, we estimated the slip rates and fault coupling on the Kunlun fault in 1991–2001 and 2014–2017. Results show an increase of slip rates and eastward migration of high fault coupling on the Kunlun fault after 2001. We propose the temporal variations are a result of the eastward accelerating movement, as a whole, of the Bayanhar block, whose boundaries were decoupled by several large earthquakes since 1997. Moreover, our results show the accumulated elastic strains along the Alake Lake-Tuosuo Lake segments could be balanced by an Mw 7.4–7.7 earthquake

Geodetic observations of shallow creep on the Haiyuan fault, northeastern Tibet

Geodetic observations of shallow creep on the Haiyuan fault, northeastern Tibe

Observation géodésique et modélisation de la déformation des failles dans le Plateau Tibétain

Ongoing plate convergence between India and Eurasia during the past ∼40 million years has created the Tibetan Plateau, a region with average elevation of ~4500 m, area of over 600×1000 km2, and active faulting and crustal deformation extends more than 2000 km into central Asia. Approximately one-half of India’s 36–40 mm/a northward motion is partitioned in the Tibetan Plateau, resulting in crustal thickening, shortening, folds, and complex fault systems. The active crustal deformation cause diverse styles of strain accumulation and release on crustal faults, expressed as distinct faulting behavior or earthquake cycles. Investigating into crustal fault deformation and earthquake cycles in the Tibetan Plateau using space-based geodesy, i.e., Global Positioning System (GPS) and Synthetic Aperture Radar Interferometry (InSAR), has started 30 years ago. Currently, high spatial-temporal resolution geodesy provides us with abundant data and sufficient resolution to study the ground deformation associated with earthquake cycle processes.In this dissertation, I focus on the interseismic deformation along three boundary large strike-slip fault systems of the Tibetan Plateau, the Altyn Tagh fault, the Haiyuan fault system and the Xianshuihe-Anninghe-Zemuhe-Xiaojiang fault system (XAZX). I use GPS (1999-2018) and InSAR (2003-2016) geodetic observations, along with 2D dislocation and 3D block models, to invert for slip rates and interseismic fault coupling, assess seismic hazard and investigate earthquake cycles along these faults; moreover, study the kinematics of deformation across the Tibetan Plateau. My results show slip rates ranging from ~2 to ~12 mm/a, highly heterogeneous interseismic fault coupling (fully locked coexist with fully creeping), distinct seismic potential and different earthquake cycles along these faults. In particular, I identify two and one new aseismic creeping segments along the Haiyuan fault system and the Xianshuihe fault respectively. My geodetic observation and modeling results demonstrate the spatio-temporal diversity and complexity of interseismic fault deformation in the Tibetan Plateau, highlight the significance of considering vertical deformation in InSAR, and allow a new and in-depth understanding of earthquake cycles along the above three fault systems.La convergence continue des plaques entre l'Inde et l'Eurasie au cours des ∼40 millions d'années a créé le plateau tibétain, une région avec une altitude moyenne de ~4500 m, une superficie de plus de 600×1000 km2, et des failles actives et une déformation crustale s'étendent sur plus de 2000 km Asie centrale. Environ la moitié des 36 à 40 mm/a de l’Inde vers le nord se répartit dans le plateau tibétain, ce qui entraîne un épaississement, un raccourcissement, des plis et des systèmes de failles complexes. La déformation crustale active provoque divers styles d'accumulation et de libération de déformation sur les failles crustales, exprimées sous la forme de comportements de failles ou de cycles sismiques distincts. L'étude de la déformation des failles crustales et des cycles sismiques sur le plateau tibétain à l'aide de la géodésie spatiale, c'est-à-dire le système de positionnement global (GPS) et l'interférométrie radar à ouverture synthétique (InSAR), a commencé il y a 30 ans. Actuellement, la géodésie à haute résolution spatio-temporelle nous fournit des données abondantes et une résolution suffisante pour étudier la déformation de la surface du sol associée aux processus du cycle sismique.Dans cette dissertation, je me concentre sur la déformation intersismique le long de trois grands systèmes de failles de glissement du plateau tibétain, la faille Altyn Tagh, le système de failles Haiyuan et le système de failles Xianshuihe-Anninghe-Zemuhe-Xiaojiang (XAZX). J'utilise les observations géodésiques GPS (1999–2018) et InSAR (2003–2016), ainsi que les modèles de dislocations 2D et de blocs 3D, pour inverser les taux de glissement et le couplage des failles intersismiques, évaluer le risque sismique et étudier les cycles sismiques le long de ces failles ; étudier en outre la cinématique de la déformation à travers le plateau tibétain. Mes résultats montrent des taux de glissement allant de ~2 à ~12 mm/a, un couplage de failles intersismiques très hétérogène (coexistant complètement verrouillé avec un fluage total), un potentiel sismique distinct et différents cycles de tremblement de terre le long de ces failles. En particulier, j'identifie deux et un nouveaux segments rampants asismiques le long du système de faille Haiyuan et de la faille Xianshuihe respectivement. Mes résultats d'observation et de modélisation géodésiques démontrent la diversité spatio-temporelle et la complexité de la déformation interstismique des failles dans le plateau tibétain, mettent en évidence l'importance de considérer la déformation verticale dans InSAR et permettent une compréhension nouvelle et approfondie des cycles sismiques le long des trois failles ci-dessus système

Geodetic observation and modelling of fault deformation in the Tibetan Plateau

La convergence continue des plaques entre l'Inde et l'Eurasie au cours des ∼40 millions d'années a créé le plateau tibétain, une région avec une altitude moyenne de ~4500 m, une superficie de plus de 600×1000 km2, et des failles actives et une déformation crustale s'étendent sur plus de 2000 km Asie centrale. Environ la moitié des 36 à 40 mm/a de l’Inde vers le nord se répartit dans le plateau tibétain, ce qui entraîne un épaississement, un raccourcissement, des plis et des systèmes de failles complexes. La déformation crustale active provoque divers styles d'accumulation et de libération de déformation sur les failles crustales, exprimées sous la forme de comportements de failles ou de cycles sismiques distincts. L'étude de la déformation des failles crustales et des cycles sismiques sur le plateau tibétain à l'aide de la géodésie spatiale, c'est-à-dire le système de positionnement global (GPS) et l'interférométrie radar à ouverture synthétique (InSAR), a commencé il y a 30 ans. Actuellement, la géodésie à haute résolution spatio-temporelle nous fournit des données abondantes et une résolution suffisante pour étudier la déformation de la surface du sol associée aux processus du cycle sismique.Dans cette dissertation, je me concentre sur la déformation intersismique le long de trois grands systèmes de failles de glissement du plateau tibétain, la faille Altyn Tagh, le système de failles Haiyuan et le système de failles Xianshuihe-Anninghe-Zemuhe-Xiaojiang (XAZX). J'utilise les observations géodésiques GPS (1999–2018) et InSAR (2003–2016), ainsi que les modèles de dislocations 2D et de blocs 3D, pour inverser les taux de glissement et le couplage des failles intersismiques, évaluer le risque sismique et étudier les cycles sismiques le long de ces failles ; étudier en outre la cinématique de la déformation à travers le plateau tibétain. Mes résultats montrent des taux de glissement allant de ~2 à ~12 mm/a, un couplage de failles intersismiques très hétérogène (coexistant complètement verrouillé avec un fluage total), un potentiel sismique distinct et différents cycles de tremblement de terre le long de ces failles. En particulier, j'identifie deux et un nouveaux segments rampants asismiques le long du système de faille Haiyuan et de la faille Xianshuihe respectivement. Mes résultats d'observation et de modélisation géodésiques démontrent la diversité spatio-temporelle et la complexité de la déformation interstismique des failles dans le plateau tibétain, mettent en évidence l'importance de considérer la déformation verticale dans InSAR et permettent une compréhension nouvelle et approfondie des cycles sismiques le long des trois failles ci-dessus systèmesOngoing plate convergence between India and Eurasia during the past ∼40 million years has created the Tibetan Plateau, a region with average elevation of ~4500 m, area of over 600×1000 km2, and active faulting and crustal deformation extends more than 2000 km into central Asia. Approximately one-half of India’s 36–40 mm/a northward motion is partitioned in the Tibetan Plateau, resulting in crustal thickening, shortening, folds, and complex fault systems. The active crustal deformation cause diverse styles of strain accumulation and release on crustal faults, expressed as distinct faulting behavior or earthquake cycles. Investigating into crustal fault deformation and earthquake cycles in the Tibetan Plateau using space-based geodesy, i.e., Global Positioning System (GPS) and Synthetic Aperture Radar Interferometry (InSAR), has started 30 years ago. Currently, high spatial-temporal resolution geodesy provides us with abundant data and sufficient resolution to study the ground deformation associated with earthquake cycle processes.In this dissertation, I focus on the interseismic deformation along three boundary large strike-slip fault systems of the Tibetan Plateau, the Altyn Tagh fault, the Haiyuan fault system and the Xianshuihe-Anninghe-Zemuhe-Xiaojiang fault system (XAZX). I use GPS (1999-2018) and InSAR (2003-2016) geodetic observations, along with 2D dislocation and 3D block models, to invert for slip rates and interseismic fault coupling, assess seismic hazard and investigate earthquake cycles along these faults; moreover, study the kinematics of deformation across the Tibetan Plateau. My results show slip rates ranging from ~2 to ~12 mm/a, highly heterogeneous interseismic fault coupling (fully locked coexist with fully creeping), distinct seismic potential and different earthquake cycles along these faults. In particular, I identify two and one new aseismic creeping segments along the Haiyuan fault system and the Xianshuihe fault respectively. My geodetic observation and modeling results demonstrate the spatio-temporal diversity and complexity of interseismic fault deformation in the Tibetan Plateau, highlight the significance of considering vertical deformation in InSAR, and allow a new and in-depth understanding of earthquake cycles along the above three fault systems

GPS-Derived Fault Coupling of the Longmenshan Fault Associated with the 2008 Mw Wenchuan 7.9 Earthquake and Its Tectonic Implications

Investigating relationships between temporally- and spatially-related continental earthquakes is important for a better understanding of the crustal deformation, the mechanism of earthquake nucleation and occurrence, and the triggering effect between earthquakes. Here we utilize Global Positioning System (GPS) velocities before and after the 2008 Mw 7.9 Wenchuan earthquake to invert the fault coupling of the Longmenshan Fault (LMSF) and investigate the impact of the 2008 Mw 7.9 Wenchuan earthquake on the 2013 Mw 6.6 Lushan earthquake. The results indicate that, before the 2008 Mw 7.9 Wenchuan earthquake, fault segments were strongly coupled and locked at a depth of ~18 km along the central and northern LMSF. The seismic gap between the two earthquake rupture zones was only locked at a depth < 5 km. The southern LMSF was coupled at a depth of ~10 km. However, regions around the hypocenter of the 2013 Mw 6.6 Lushan earthquake were not coupled, with an average coupling coefficient ~0.3. After the 2008 Mw 7.9 Wenchuan earthquake, the central and northern LMSF, including part of the seismic gap, were decoupled, with an average coupling coefficient smaller than 0.2. The southern LMSF, however, was coupled to ~20 km depth. Regions around the hypocenter of the 2013 Mw 6.6 Lushan earthquake were also coupled. Moreover, by interpreting changes of the GPS velocities before and after the 2008 Mw 7.9 Wenchuan earthquake, we find that the upper crust of the eastern Tibet (i.e., the Bayan Har block), which was driven by the postseismic relaxation of the 2008 Mw 7.9 Wenchuan earthquake, thrust at an accelerating pace to the Sichuan block and result in enhanced compression and shear stress on the LMSF. Consequently, downdip coupling of the fault, together with the rapid accumulation of the elastic strain, lead to the occurrence of the 2013 Mw 6.6 Lushan earthquake. Finally, the quantity analysis on the seismic moment accumulated and released along the southern LMSF show that the 2013 Mw 6.6 Lushan earthquake should be defined as a “delayed” aftershock of the 2008 Mw 7.9 Wenchuan earthquake. The seismic risk is low along the seismic gap, but high on the unruptured southwesternmost area of the 2013 Mw 6.6 Lushan earthquake

Bayesian modeling of fault slip and interseismic coupling along the Tuosuo Lake segment of the Kunlun fault

Bayesian modeling of fault slip and interseismic coupling along the Tuosuo Lake segment of the Kunlun faul