2,204 research outputs found
Ethyl 2-phenyl-5-trifluoromethyl-1,3-thiazole-4-carboxylate
In the title compound, C13H10F3NO2S, the dihedral angle between the thiazole and phenyl rings is 5.15 (1)°. No intermolecular hydrogen bonding is observed in the crystal structure
Along-strike variation in slab geometry at the southern Mariana subduction zone revealed by seismicity through ocean bottom seismic experiments
Author Posting. © The Authors, 2019. This article is posted here by permission of The Royal Astronomical Society for personal use, not for redistribution. The definitive version was published in Geophysical Journal International 218(3), (2019): 2122-2135, doi: 10.1093/gji/ggz272.We have conducted the first passive Ocean Bottom Seismograph (OBS) experiment near the Challenger Deep at the southernmost Mariana subduction zone by deploying and recovering an array of 6 broad-band OBSs during December 2016–June 2017. The obtained passive-source seismic records provide the first-ever near-field seismic observations in the southernmost Mariana subduction zone. We first correct clock errors of the OBS recordings based on both teleseismic waveforms and ambient noise cross-correlation. We then perform matched filter earthquake detection using 53 template events in the catalogue of the US Geological Survey and find >7000 local earthquakes during the 6-month OBS deployment period. Results of the two independent approaches show that the maximum clock drifting was ∼2 s on one instrument (OBS PA01), while the rest of OBS waveforms had negligible time drifting. After timing correction, we locate the detected earthquakes using a newly refined local velocity model that was derived from a companion active source experiment in the same region. In total, 2004 earthquakes are located with relatively high resolution. Furthermore, we calibrate the magnitudes of the detected earthquakes by measuring the relative amplitudes to their nearest relocated templates on all OBSs and acquire a high-resolution local earthquake catalogue. The magnitudes of earthquakes in our new catalogue range from 1.1 to 5.6. The earthquakes span over the Southwest Mariana rift, the megathrust interface, forearc and outer-rise regions. While most earthquakes are shallow, depths of the slab earthquakes increase from ∼100 to ∼240 km from west to east towards Guam. We also delineate the subducting interface from seismicity distribution and find an increasing trend in dip angles from west to east. The observed along-strike variation in slab dip angles and its downdip extents provide new constraints on geodynamic processes of the southernmost Mariana subduction zone.We express our appreciation to the science parties and crew members of the R/V Shiyan 3 for deployment and collection of the OBS instruments during the Mariana expeditions. This study is supported by the Hong Kong Research Grant Council Grants (No. 14313816), Faculty of Science at CUHK, Chinese Academy of Sciences (No. Y4SL021001, QYZDY-SSW-DQC005, 133244KYSB20180029), the National Natural Science Foundation of China (No. 41890813, 91628301, 41676042, U1701641, 41576041, 91858207 and U1606401), the National Key R&D Program of China (2018YFC0309800 and 2018YFC0310100). Generic Mapping Tools (Wessel & Smith 1991) and PSSAC (developed by Prof Lupei Zhu) are used for data analysis and figure preparation in this study. Constructive comments from Dr Lidong Bie and two anonymous reviewers are helpful in improving the manuscript
The prevalence of gastro-esophageal reflux disease and esophageal dysmotility in Chinese patients with idiopathic pulmonary fibrosis
Deep seismic structure across the southernmost Mariana trench: Implications for arc rifting and plate hydration
Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research-Solid Earth 124(5), (2019): 4710-4727, doi:10.1029/2018JB017080.The southernmost Mariana margin lacks a mature island arc and thus differs significantly from the central‐north Mariana and Izu‐Bonin margins. This paper presents a new P wave velocity model of the crust and uppermost mantle structure based on a 349‐km‐long profile of wide‐angle reflection/refraction data. The active source seismic experiment was conducted from the subducting Pacific plate to the overriding Philippine plate, passing through the Challenger Deep. The subducting plate has an average crustal thickness of ~6.0 km with Vp of 7.0 ± 0.2 km/s at the base of the crust and low values of only 5.5–6.9 km/s near the trench axis. The uppermost mantle of the subducting plate is characterized by low velocities of 7.0–7.3 km/s. The overriding plate has a maximum crustal thickness of ~18 km beneath the forearc with Vp of ~7.4 km/s at the crustal bottom and 7.5–7.8 km/s in the uppermost mantle. A zone of slight velocity reduction is imaged beneath the Southwest Mariana Rift that is undergoing active rifting. The observed significant velocity reduction in a near‐trench crustal zone of ~20–30 km in the subducting plate is interpreted as a result of faulting‐induced porosity changes and fracture‐filling fluids. The velocity reduction in the uppermost mantle of both subducting and overriding plates is interpreted as mantle serpentinization with fluid sources from dehydration of the subducting plate and/or fluid penetration along faults.Data acquisition and sample collections were supported by the Mariana Trench Initiative of the Chinese Academy of Sciences (CAS). We are grateful to the science parties and crews of R/V Shiyan 3 of the South China Sea Institute of Oceanology, CAS, for contributions to data acquisition. Constructive reviews by Robert Stern, Martha Savage, and anonymous reviewers significantly improved the manuscript. We thank Gaohua Zhu, Fan Zhang, Chunfeng Li, Zhen Sun, Zhi Wang, and Minghui Zhao for helpful discussion. The bathymetric maps were plotted using GMT (Wessel & Smith, 1995). Digital files of the velocity models and selected raw data are deposited and accessible online (at https://pan.baidu.com/s/1AbDJOgLZhYn1C‐3sg7S9Xw). This work was supported by the Strategic Priority Program of CAS (XDA13010101), CAS (Y4SL021001, QYZDY‐SSW‐DQC005, and 133244KYSB20180029), Key Laboratory of Ocean and Marginal Sea Geology, CAS (OMG18‐03), National Natural Science Foundation of China (41890813, 41676042, U1701641, 91628301, 41576041, and U1606401), and HKSAR Research Grant Council grants (14313816).2019-10-0
Nanoscale integrin cluster dynamics controls cellular mechanosensing via FAKY397 phosphorylation
Transduction of extracellular matrix mechanics affects cell migration, proliferation, and differentiation. While this mechanotransduction is known to depend on the regulation of focal adhesion kinase phosphorylation on Y397 (FAKpY397), the mechanism remains elusive. To address this, we developed a mathematical model to test the hypothesis that FAKpY397-based mechanosensing arises from the dynamics of nanoscale integrin clustering, stiffness-dependent disassembly of integrin clusters, and FAKY397 phosphorylation within integrin clusters. Modeling results predicted that integrin clustering dynamics governs how cells convert substrate stiffness to FAKpY397, and hence governs how different cell types transduce mechanical signals. Existing experiments on MDCK cells and HT1080 cells, as well as our new experiments on 3T3 fibroblasts, confirmed our predictions and supported our model. Our results suggest a new pathway by which integrin clusters enable cells to calibrate responses to their mechanical microenvironment
Wuzi Yanzong Pill—Based on Network Pharmacology and In Vivo Evidence—Protects Against Spermatogenesis Disorder via the Regulation of the Apoptosis Pathway
The crisis of male infertility is an issue of human reproductive health worldwide. The Wuzi Yanzong pill (WZYZP) is a traditional Chinese medicine prescription that shows efficacy in kidney reinforcement and essence benefit to ameliorate male reproductive dysfunctions. However, the pharmacological mechanisms of the WZYZP on male infertility have not been investigated and clarified clearly. This study was designed to investigate the effects of the WZYZP on spermatogenesis disorder and explore its underlying pharmacological mechanisms. First, based on a network pharmacology study, 39 bioactive compounds and 40 targets of the WZYZP associated with spermatogenesis disorder were obtained, forming a tight compound-target network. Molecular docking tests showed tight docking of these compounds with predicted targeted proteins. The protein–protein interaction (PPI) network identified TP53, TNF, AKT1, Bcl-XL, Bcl-2, and IκBA as hub targets. The Kyoto Encyclopedia of Genes and Genomes pathway network and pathway-target-compound network revealed that the apoptosis pathway was enriched by multiple signaling pathways and multiple targets, including the hub targets. Subsequently, the chemical characterization of WZYZP was analyzed using liquid chromatography to quadrupole/time-of-flight mass spectrometry, and 40 compounds in positive ion mode and 41 compounds in negative ion mode in the WZYZP were identified. Furthermore, based on the prediction of a network pharmacology study, a rat model of spermatogenesis disorder was established to evaluate the curative role and underlying mechanisms of the WZYZP. The results showed that WZYZP treatment improved rat sperm quality and attenuated serum hormone levels, reversed histopathological damage of the testis, reduced cell apoptosis in testis tissues, and ameliorated the expression of the predicted hub targets (TP53, TNF-α, AKT1, NFκB, and IκBA) and the apoptosis related proteins (Bcl-XL, Bcl-2, Bax, Caspase 3, and Caspase 9). These results indicated that the WZYZP has a protective effect on spermatogenesis disorder, suggesting that it could be an alternative choice for male infertility therapy
Manipulation of ray polarization in Compton scattering
High-brilliance high-polarization rays based on Compton scattering
are of great significance in broad areas, such as nuclear, high-energy,
astro-physics, etc. However, the transfer mechanism of spin angular momentum in
the transition from linear, through weakly into strongly nonlinear processes is
still unclear, which severely limits the simultaneous control of brilliance and
polarization of high-energy rays. In this work, we investigate the
manipulation mechanism of high-quality polarized rays in Compton
scattering of the ultrarelativistic electron beam colliding with an intense
laser pulse. We find that the contradiction lies in the simultaneous
achievement of high-brilliance and high-polarization of rays by
increasing laser intensity, since the polarization is predominately contributed
by the electron spin via multi-photon absorption channels. For instances, the
spin-polarized electrons in high-intensity laser pulse can radiate
high-brilliance high-polarization rays, while, for the
spin-nonpolarized electrons, to achieve the similar high-quality beams
with the same laser, the electrons must hold higher energies due to the spin
contribution mainly from the laser via the single-photon absorption channel.
Moreover, we confirm that the signature of ray polarization can be
applied for observing the nonlinear effects (multi-photon absorption) of
Compton scattering with moderate-intensity laser facilities
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