3-D Modeling of Shear-Wave Velocity for Numerical Green’s Function in Near-Field Ground Motion Simulation

Numerical Green’s function is effective for simulating low-frequency ground motions in the near field, in which the whole computing region is divided into a homogenous zone including the source and an inhomogeneous zone (named overburden layer) from the ground surface to a certain depth. In this paper, a procedure to build a 3-D model that properly describes the shear-wave velocity structure of overburden layer and the topography of ground surface was presented. In this procedure, the overburden layer is discretized into finite elements based on the topography of ground surface and buried rock surface; shear-wave velocity data from inversion, surveying line and borehole are assigned to elements according to their locations in the overburden layer. For elements without available velocity data, a Kriging interpolation method based on the spherical variation function model was employed, and dummy borehole is also used to improve the validity of the interpolation based on sparse data. Particularly, block interpolation and interface smooth was suggested for computing region that contains several different geological conditions, such like a sedimentary basin and its vicinity. As an example, the 3-D shear-wave velocity of the Lanzhou sedimentary basin and its vicinity in Gansu, China was modeled using the procedure. Low-frequency ground motions at 10854 surface points in this region was simulated by Numerical Green’s function based on this velocity model, among which ground motions at 7 representative points were compared with those simulated based on horizontal layered velocity model

Epigenetic regulation of CD271, a potential cancer stem cell marker associated with chemoresistance and metastatic capacity.

Cancer stem cells (CSCs) are considered to be the cause of tumor initiation, metastasis and recurrence. Additionally, CSCs are responsible for the failure of chemotherapy and radiotherapy. The isolation and identification of CSCs is crucial for facilitating the monitoring, therapy or prevention of cancer. We aimed to identify esophageal squamous cell carcinoma (ESCC) stem-like cells, the epigenetic mechanism and identify novel biomarkers for targeting ESCC CSCs. Sixty-three paired ESCC tissues and adjacent non-cancerous tissues were included in this study. CD271, which was identified as the CSC marker for melanoma, was assessed using quantitative PCR (qPCR). Using flow cytometry, we isolated CD271+ cells comprising 7.5% of cancer cells from the KYSE70 cell line. Sphere formation and anchorage-independent growth were analyzed in CD271+ and CD271- cancer cells, respectively. qPCR was used to detect stem-related genes and CCK-8 was performed to analyze the sensitivity to chemotherapy in the two groups. Bisulfite genomic sequencing was used to analyze the methylation status. CD271 expression was significantly higher in ESCC tissues than in adjacent non-cancerous tissues. Compared with CD271- cancer cells, CD271+ cancer cells showed a higher ability of sphere and colony formation, a high level expression of stem-related gene, and resistance to chemotherapy. The expression of CD271 was induced by a demethylation agent. In conclusion, CD271+ ESCC cells possess stem-like properties. CD271 can potentially act as a prognostic marker for ESCC, whose expression is regulated epigenetically

The moderating effects of slack on the relationship between ambidextrous strategy and performance: evidence from high-tech firms in China

The purpose of this study is to examine the impacts of ambidexterity of exploration/exploitation on long-term performance and the moderating effects of slack resources. The methodology adopted is panel data analysis of a sample dataset of 125 high technology firms in China. The finding of this study shows that a moderating role of organizational slack between ambidexterity and long-term performance is strongly supported. The research and practical implications of this paper are: (1) Exploration and exploitation can be mutually enhancing instead of being fundamentally contradictory; (2) Slack resources moderate the relationship between ambidexterity and performance. The originality and value of the paper is that it is one of the earliest studies that empirically examine the moderating effects of slack resources on ambidexterity-performance relationship

Neutralization of IL- 10 produced by B cells promotes protective immunity during persistent HCV infection in humanized mice

Chronic HCV infection can lead to cirrhosis and is associated with increased mortality. Interleukin (IL)- 10- producing B cells (B10 cells) are regulatory cells that suppress cellular immune responses. Here, we aimed to determine whether HCV induces B10 cells and assess the roles of the B10 cells during HCV infection. HCV- induced B10 cells were enriched in CD19hi and CD1dhiCD5+ cell populations. HCV predominantly triggered the TLR2- MyD88- NF- κB and AP- 1 signaling pathways to drive IL- 10 production by B cells. In a humanized murine model of persistent HCV infection, to neutralize IL- 10 produced by B10 cells, mice were treated with pcCD19scFv- IL- 10R, which contains the genes coding the anti- CD19 single- chain variable fragment (CD19scFv) and the extracellular domain of IL- 10 receptor alpha chain (sIL- 10Ra). This treatment resulted in significant reduction of B10 cells in spleen and liver, increase of cytotoxic CD8+ T- cell responses against HCV, and low viral loads in infected humanized mice. Our results indicate that targeting B10 cells via neutralization of IL- 10 may offer a novel strategy to enhance anti- HCV immunotherapy.HCV predominantly triggers the TLR2- MyD88- NF- κB and AP- 1 signaling pathways to drive IL- 10 production by B cells. Neutralization of IL- 10 produced by B10 cells promotes anti- HCV immunity in a humanized murine model of persistent HCV infection. These results provide insight into a novel immunotherapy strategy for HCV treatment.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162732/2/eji4736.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162732/1/eji4736_am.pd

Holocene Earthquake Cycles of an Active Tectonic Block Boundary Fault Zone: A Case Study in the Qilian–Haiyuan Fault Zone, Northeastern Tibet Plateau

Fault zones along active tectonic block boundaries are a significant source of devastating continental earthquakes. Strong earthquakes produce disruptions of sediment and induce characteristic sediments near the fault, which serve as valuable sedimentary evidence for identifying and dating of paleoearthquakes. In this study, we aimed to reconstruct the earthquake history of the Qilian–Haiyuan fault zone in the northeastern Tibetan Plateau during the Holocene. We reanalyzed forty-four trenches and used the sedimentary sequences, event indicators, and age constraints to determine the earthquake history. Our analysis revealed the paleoearthquakes of 6 subsidiary faults of the Qilian–Haiyuan fault zone with accurate event ages and rupture extents. Based on the spatial and temporal distributions of strong earthquakes since 10 ka, we identified five earthquake clusters around the central-eastern Qilian–Haiyuan fault zone including seven rupture cascades where the earthquakes migrated gradually from east to west. The existing seismic gap reveals that the latest migration may not yet be complete and suggests a high probability of M ≥ 7 earthquakes occurring on the Jinqianghe fault, Maomaoshan fault, and the central part of the Lenglongling faults. We concluded that, in order to better understand earthquake cycles and seismic hazards, it is important to consider a fault zone as a whole, including multiple faults and their interaction on the earthquake triggering between nearby faults

The GECAM Real-Time Burst Alert System

Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor (GECAM), consisting of two micro-satellites, is designed to detect gamma-ray bursts associated with gravitational-wave events. Here, we introduce the real-time burst alert system of GECAM, with the adoption of the BeiDou-3 short message communication service. We present the post-trigger operations, the detailed ground-based analysis, and the performance of the system. In the first year of the in-flight operation, GECAM was triggered by 42 GRBs. GECAM real-time burst alert system has the ability to distribute the alert within $\sim$1 minute after being triggered, which enables timely follow-up observations.Comment: 17 pages, 10 figures; Accepted for publication in RA

Scopararanes C–G: New Oxygenated Pimarane Diterpenes from the Marine Sediment-Derived Fungus Eutypella scoparia FS26

Five new oxygenated pimarane diterpenes, named scopararanes C–G (1–5) were isolated from the culture of a marine sediment-derived fungus Eutypella scoparia FS26 obtained from the South China Sea. The structures of these compounds were established on the basis of extensive spectroscopic analysis. The absolute configurations of compounds 1–5, were determined by CD spectroscopic analysis and comparison with literature data. All isolated compounds (1–5) were evaluated for their cytotoxic activities against MCF-7, NCI-H460, and SF-268 tumor cell lines by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) method