<i>V</i>_s30 Prediction Models Based on Measured Shear-Wave Velocities in Tangshan, China

Vs30 (equivalent shear-wave velocity of soil layers within a depth of 30 m underground) is widely used in the field of seismic engineering; however, due to the limitation of funds, time, measuring devices, and other factors, the depth for testing shear-wave velocity in an engineering site rarely reaches 30 m underground. Therefore, it is necessary to predict Vs30 effectively. We analyzed the existing models using 343 boreholes with depths greater than 30 m in Tangshan, China. It shows that the topographic slope method is not suitable for predicting Vs30 in Tangshan. The Boore (2011) model overestimates, while Boore (2004) underestimates Vs30 in Tangshan, while Junju Xie’s (2016) model has ideal prediction results. We propose three new models in this paper, including the bottom constant velocity (BCV) model, linear model, and conditional independent model. We find that the BCV model has limited prediction ability, and the linear model is more suitable when z ≤ 18 m, while the conditional independent model shows good performance under conditions where z > 18 m. We propose that the model can be accurately and effectively applied in Tangshan and other regions with low shear-wave velocity

Novel Polymer Material for Efficiently Removing Methylene Blue, Cu(II) and Emulsified Oil Droplets from Water Simultaneously

The pollution of water resources has become a worldwide concern. The primary pollutants including insoluble oil, toxic dyes, and heavy metal ions. Herein, we report a polymer adsorbent, named SPCT, to remove the above three contaminants from water simultaneously. The preparation process of SPCT contains two steps. Firstly, a hydrogel composed of sulfonated phenolic resin (SMP) and polyethyleneimine (PEI) was synthesized using glutaraldehyde (GA) as the crosslinking agent, and the product was named SPG. Then SPCT was prepared by the reaction between SPG and citric acid (CA) at 170 ∘ C. SPCT exhibited an excellent performance for the removal of methylene blue (MB) and Cu(II) from aqueous solution. For a solution with a pollutant concentration of 50 mg L&#8722;1, a removal efficiency of above 90% could be obtained with a SPCT dosage of 0.2 g L&#8722;1 for MB, or a SPCT dosage of 0.5 g L&#8722;1 for Cu(II), respectively. SPCT also presented an interesting wettability. In air, it was both superhydrophilic and superoleophilic, and it was superoleophobic underwater. Therefore, SPCT could successfully separate oil-in-water emulsion with high separation efficiency and resistance to oil fouling. Additionally, SPCT was easily regenerated by using dilute HCl solution as an eluent. The outstanding performance of SPCT and the efficient, cost-effective preparation process highlight its potential for practical applications

Micro-seismic events detection and its tectonic implications in Northeastern Hainan Province

In this paper, we combine the U-net-based phase picking method (PhaseNet) with Graphics Processing Unit-Based Match and Locate technology (GPU-M&amp;L) and a deep-learning-based seismic signal de-noising method (DeepDenoiser) as a workflow for automatically extracting micro-seismic information from continuous raw seismic data. PhaseNet is first used to detect missed seismic phases by scanning through the 5-year continuous waveform data recorded at five broad-band stations in Hainan province. Then Rapid Earthquake Association and Location method (REAL), VELEST program (1-D inversion of velocities and hypocenter locating) and HypoDD (a double-difference locating method) are applied to associate seismic phases with events and to locate, respectively. This initially established catalogue can be served as the template for the following match-filter work. We choose events with a high signal-to-noise ratio (SNR) as templates and apply GPU-M&amp;L to detect more small earthquakes which are difficult to pick by routine methods due to the low SNR. Then, a deep learning-based noise reduction technique named DeepDenoiser is applied to extract seismic signal from noise to provide a better picking of arrival time and then to improve the relocation effects. Finally, we use HypoDD to relocate these events with P- and S- wave arrival times picked by PhaseNet. Compared with the five events listed in the China Earthquake Networks Center routine catalogue, in this study, we detect and locate 977 earthquakes by following the above procedure. Our relocation results illustrate quite a complex distribution pattern of events due to the complicated fault system in the northeastern part of Hainan Province

SIRT6 promotes osteogenic differentiation of mesenchymal stem cells through BMP signaling

Abstract SIRT6 has been identified as an H3K9 deacetylase and a critical regulator of genome stability, telomere integrity, and metabolic homeostasis. Sirt6-deficient mice displayed dramatic phenotypes including profound lymphopenia, loss of subcutaneous fat, lordokyphosis and low bone marrow density. Here, we report that SIRT6 regulates osteogenic differentiation independent of its deacetylase activity in vitro. Further mechanistic studies showed that SIRT6 involves the cell fate determination by modulating bone morphogenetic protein (BMP) signaling. Unexpectedly, this modulation depends upon P300/CBP-associated factor (PCAF). In addition, we observed impaired SIRT6 expression in bone marrow mesenchymal stem cells and in bone sections of ovariectomized mice. Taken together, our present study provide new insights into mechanisms of SIRT6-regulated MSC function beyond its H3K9 deacetylase activity

LRRC15 promotes osteogenic differentiation of mesenchymal stem cells by modulating p65 cytoplasmic/nuclear translocation

Abstract Background Mesenchymal stem cells (MSCs) are a reliable resource for bone regeneration and tissue engineering, but the molecular mechanisms of differentiation remain unclear. The tumor antigen 15-leucine-rich repeat containing membrane protein (LRRC15) is a transmembrane protein demonstrated to play important roles in cancer. However, little is known about its role in osteogenesis. This study was to evaluate the functions of LRRC15 in osteogenic differentiation of MSCs. Methods Osteogenic-induction treatment and the ovariectomized (OVX) model were performed to investigate the potential relationship between LRRC15 and MSC osteogenesis. A loss-of-function study was used to explore the functions of LRRC15 in osteogenic differentiation of MSCs in vitro and in vivo. NF-κB pathway inhibitor BAY117082, siRNA, nucleocytoplasmic separation, and ChIP assays were performed to clarify the molecular mechanism of LRRC15 in bone regulation. Results Our results first demonstrated that LRRC15 expression was upregulated upon osteogenic induction, and the level of LRRC15 was significantly decreased in OVX mice. Both in-vitro and in-vivo experiments detected that LRRC15 was required for osteogenesis of MSCs. Mechanistically, LRRC15 inhibited transcription factor NF-κB signaling by affecting the subcellular localization of p65. Further studies indicated that LRRC15 regulated osteogenic differentiation in a p65-dependent manner. Conclusions Taken together, our findings reveal that LRRC15 is an essential regulator for osteogenesis of MSCs through modulating p65 cytoplasmic/nuclear translocation, and give a novel hint for MSC-mediated bone regeneration

Expression of MicroRNA-301a and its Functional Roles in Malignant Melanoma

Background/Aims: Although microRNA-301a has been reported to function as an oncogene in many human cancers, the roles of miR-301a in malignant melanoma (MM) is unclear. The present study aims to investigate the functional roles of miR-301a in MM and its possible molecular mechanisms. Methods: Quantitative real-time PCR (qRT-PCR) assay was performed to detect the expression of miR-301a in MM tissues, and analyze its correlation with metastasis and prognosis of MM patients. In vitro, miR-301a was ectopically expressed using overexpression and knock-down strategies, and the effects of miR-301a expression on growth, apoptosis, migration, invasion and chemosensitivity of MM cells were further investigated. Furthermore, the potential and functional target gene was identified by luciferase reporter, qRT-PCR, Western blot assays. Results: We showed that the expression of miR-301a was significantly upregulated in MM tissues, and upregulation of miR-301a correlated with metastasis and poor prognosis of MM patients. Transfection of miR-301a/inhibitor significantly inhibited growth, colony formation, migration, invasion and enhanced apoptosis and chemosensitivity in MM cells, while transfection of miR-301a/mimic could induce the inverse effects on phenotypes of MM cells. Luciferase reporter, qRT-PCR and Western blot assays showed that phosphatase and tensin homolog (PTEN) was a direct and functional target of miR-301a. It was also observed that the Akt and FAK signaling pathways were involved in miR-301/PTEN-promoting MM progression. Conclusion: Taken together, our study suggests that miR-301a may be used as a potential therapeutic target in the treatment of human MM

Effect of Different Groundwater Levels on Seismic Dynamic Response and Failure Mode of Sandy Slope

<div><p>Heavy seismic damage tends to occur in slopes when groundwater is present. The main objectives of this paper are to determine the dynamic response and failure mode of sandy slope subjected simultaneously to seismic forces and variable groundwater conditions. This paper applies the finite element method, which is a fast and efficient design tool in modern engineering analysis, to evaluate dynamic response of the slope subjected simultaneously to seismic forces and variable groundwater conditions. Shaking table test is conducted to analyze the failure mode and verify the accuracy of the finite element method results. The research results show that dynamic response values of the slope have different variation rules under near and far field earthquakes. And the damage location and pattern of the slope are different in varying groundwater conditions. The destruction starts at the top of the slope when the slope is in no groundwater, which shows that the slope appears obvious whipping effect under the earthquake. The destruction starts at the toe of the slope when the slope is in the high groundwater levels. Meanwhile, the top of the slope shows obvious seismic subsidence phenomenon after earthquake. Furthermore, the existence of the groundwater has a certain effect of damping.</p></div

Basic earthquake acceleration value.

<p>Basic earthquake acceleration value.</p

Physical parameters of slope.

<p>Physical parameters of slope.</p

Similarity constants.

<p>Similarity constants.</p