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Constraining Ω with the fluctuation of the local Hubble flow

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Chinese Journal of Astronomy and Astrophysics 2009年第2期9卷 151-156页

作者： Quan Guo huan-yuan Shan National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

We present an analysis of the fluctuation of the local Hubble flow using 350 galaxies in the Local Volume （D 〈 5 Mpc, hereafter LV） with accurate measurements of distances, positions and radial velocities, and compare the results with the theoretical prediction of the local Hubble flow induced by density perturbations. This allows us to set a useful constraint on the local Ω parameters： ΩM - 0.6 and ΩA - 0.7, which may serve as compelling evidence for the existence of dark energy in the local Universe.

关键词： cosmology dark matter -- cosmology large-scale structure of universe --galaxies peculiar -- techniques radial velocities

A regression approach for seismic first-break picking

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Petroleum Science 2024年第3期21卷 1584-1596页

作者： huan yuan San-Yi yuan Jie Wu Wen-Jing Sang Yu-He Zhao CNPC Key Laboratory of Geophysical Exploration China University of Petroleum(Beijing)Beijing 102249China Research Institute of Petroleum Exploration&Development—Northwest(NWGI) Key Laboratory of reservoir characterization of CNPCPetroChinaLanzhou 730020GansuChina

The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)***,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)*** address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target *** employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed *** from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and *** addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary *** picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large *** picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR *** subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed *** results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application.

关键词： First-break picking Low signal-to-noiseratio Regression BiLSTM Traveltime Geometry Noisy seismic data

Effects of estrogen on CD4^+ CD25^+ regulatory T cell in peripheral blood during pregnancy

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Asian Pacific Journal of Tropical Medicine 2013年第9期6卷 748-752页

作者： yuan-huan Xiong Zhen yuan Li He School of Basic Medical Sciences Wuhan.University Obstetrics and Gynecology Department People's Hospital of Jiangxi Province Medical College of Nanchang University School of Basic Medical Sciences Wuhan University

Objective To investigate the effects of estrogen(E_2)level on regulatory T cells(Treg)in peripheral blood during ***:A total of 30 healthy non-pregnant women were selected as control group,90 pregnant women of early,middle and late pregnancy and 30 postpartum women at 1 month after parturition were selected as experimental groups including early pregnancy group,middle pregnancy group and late pregnancy group;the proportions of CD4^+CD25^+Treg and CD4^+CD25^+CD127^-Treg among CD4 T cells were detected by flow cytometry;the serum estrogen content in peripheral blood was detected by electrochemical immune luminescence ***:E_2 level was coincident with the change of Tregs number during *** estrogen content in peripheral blood increased gradually from early pregnancy to late pregnancy,then decreased significantly after parturition,and the level at 1 month after parturition down to the level in non-pregnancy group(P>0.05);the level of E_2 in pregnancy groups were significantly higher than those in non-pregnancy group(P0.05):the proportions in middle and late pregnancy groups were significantly higher than those in early pregnancy group(P0.05).There was correlation between Tregs number with estrogen level during *** proportion of CD4^+CD25^+Treg and CD4^+CD25^+CD 127^-Treg were positively correlated with estrogen ***:High proportion of CD4^+CD25^+Trcg and

关键词： Estrogen CD4^+CD25^+regulatory T cell CD4^+ CD25^+ CD 127^-regulatory T cell Pregnancy Immuno-modulation

A new depsidone from Usnea diffracta

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Chinese Chemical Letters 2009年第2期20卷 187-189页

作者： huan Yang Qi yuan Peng Jin Yan Ping Shi Key Laboratory for Natural Medicine of Gansu Province Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A new depsidone, diffractione A （1）, as well as six known phenolic compounds （2-7） were isolated from Usnea diffracta. Their structures were elucidated by 1D and 2D NMR spectroscopy together with HRESIMS analysis.... 详细信息

关键词： Depsidone Usneaceae Usnea diffracta Lichen Diffractione A

Amphiphilic ABC Triblock Terpolymer Templating for Mesoporous Silica

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Chemical Research in Chinese Universities 2014年第5期30卷 863-867页

作者： WANG huan YAO yuan HAN Lu CHE Shun' ai State Key Laboratory of Metal Matrix Composites School of Chemistry and Chemical Engineering Shanghai Jiaotong University Shanghai 200240 P. R. China

Self-assembled triblock terpolymers have attracted intense attention in recent years because of their abundant variety of assembly mesostructure. We reported the synthesis of mesoporous silica materials with the am- phiphilic ABC triblock terpolymer polyethylene-poly（ethylene oxide）-polycaprolactone（PE-PEO-PCL） as a template and tetraethoxysilane（TEOS） as a silica source. Increasing the hydrophilic head group（PEO） led to the decrease of packing parameter g, which gave rise to the mesophase transformation from a cylindrical two-dimensional hexagonal P6mm structure to a cage-type face centered cubic closed-packing mesostructure. This new templating route provided a new insight into the template factor governed inorganic-organic self-assembly mesophases.

关键词： Amphiphilic triblock terpolymer Self-assembly Mesoporous material Silica

Detection of decomposition products of SF6/air gas mixture by electron attachment mass spectrometry

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High Voltage 2022年第3期7卷 536-544页

作者： huan yuan Xiaonan Wang Aijun Yang Dingxin Liu Xiaohua Wang Mingzhe Rong State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina

Sulphur hexafluoride(SF_(6))is widely used in gas insulation,and its decomposition products can be used to diagnose potential insulation *** and accurate detection of decomposition products can help to understand equipment-operating conditions in *** this study,the decomposition products of SF_(6)/air gas mixtures under different pulsed discharge voltages were *** was found that the main products were SOF_(2),SO_(2)F_(2),SO_(2),CF_(4)and SOF_(4),and the yields of SOF_(2),SO_(2)F_(2),SO_(2)and SOF_(4)increased with the number of discharge *** productive rate of SOF_(2),SO_(2)and SOF_(4)were positively correlated with the discharge voltage,and when the discharge voltage increased from 5 to 15 kV,their yields after 50,000 discharges increased by 49%,120%and 1100%,*** productive rate of SOF_(2)and SO_(2)were positively correlated with the proportion of air in the gas mixtures while that of SOF_(4)was *** the proportion of air increases from 0%to 90%,their yields after 50,000 discharges became 270%,3169%and 10%of the originals,*** addition,the productive rate of SO_(2)F_(2)was not affected by discharge voltage and the proportion of air in the gas ***_(2)F_(2),SOF_(2),SOF_(4)and SO_(2)can be used as the basis for judging the discharge failures and the discharge degree of power equipment.

关键词： insulation decomposition SF6

Research on vibration energy harvesting technology of power equipment based on alternating magnet array

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High Voltage 2024年第2期9卷 336-345页

作者： Pinlei Lv Chengyu Fan Aijun Yang huan yuan Jifeng Chu Mingzhe Rong Xiaohua Wang State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina State Grid Sichuan Electric Power Research Institute ChengduChina

Vibration with a frequency of 100 Hz is widely distributed in the power equipment,and it can provide a new way to supply energy for sensors by vibration energy *** vibration energy harvesting method based on electromagnetic induction principle was studied through the arrayed structure of magnets and *** magnetic field models were established for four magnet array structures and it was found that the alternating magnet array has the largest magnetic flux and magnetic flux *** on the alternating magnet array,prototypes of energy harvester with vertical and parallel movement mode were *** structural parameter optimisation analysis,two different energy harvesters were fabricated and it was found that the energy harvester with a parallel movement mode has better output *** energy harvester could provide output voltage/current and power of 8.35 V/17.39 mA and 15.13 mW(matched resistance is 200Ω)at an acceleration of 5 m⋅s^(-2).The 100 mF capacitor could be charged to 2.72 V within 300 s,and the final voltage of the capacitor is greater than 3 V,which could sustainably drive commercial wireless temperature/humidity sensors.

关键词： power energy alternating

Antiarrhythmic drug usage and prostate cancer： a population-based cohort study

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Asian Journal of Andrology 2018年第1期20卷 37-42页

作者： Li-Ting Kao Chung-Chien huang Herng-Ching Lin Chao-yuan huan 1Graduate Institute of Life Science National Defense Medical Center Taipei 110 Taiwan China Sleep Research Center Taipei Medical University Hospital Taipei 110 Taiwan China School of Health Care Administration Taipei Medical University Taipei 110 Taiwan China Department of Urology National Taiwan University Hospital National Taiwan University College of Medicine Taipei 110 Taiwan China Department of Urology National Taiwan University Hospital Hsin Chu Branch Hsin Chu City 100 Taiwan China School of Public Health Taipei Medical University Taipei 100 Taiwan China

Even though the relationship between antiarrhythmic drug usage and subsequent prostate cancer （PCa） risk has recently been highlighted, relevant findings in the previous literature are still inconsistent. In addition, very few studies have attempted to investigate the association between sodium channel blockers or potassium channel blockers for arrhythmia and the subsequent PCa risk. Therefore, this cohort study aimed to find the relationship between antiarrhythmic drug usage and the subsequent PCa risk using a population-based dataset. The data used in this study were derived from the Longitudinal Health Insurance Database 2005, Taiwan, China. We respectively identified 9988 sodium channel blocker users, 3663 potassium channel blocker users, 65 966 beta-blocker users, 23 366 calcium channel blockers users, and 7031 digoxin users as the study cohorts. The matched comparison cohorts （one comparison subject for each antiarrhythmic drug user） were selected from the same dataset. Each patient was tracked for a 5-year period to define those who were subsequently diagnosed with PCa. After adjusting for sociodemographic characteristics, comorbidities, and age, Cox proportional hazard regressions found that the hazard ratio （HR） of subsequent PCa for sodium channel blocker users was 1.12 （95% confidence interval [CI]： 0.84-1.50）, for potassium channel blocker users was 0.89 （95% CI. 0.59-1.34）, for beta-blocker users was 1.08 （95% Ch 0.96-1.22）, for calcium channel blocker users was 1.14 （95% Ch 0.95-1.36）, and for digoxin users was 0.89 （95% Ch 0.67-1.18）, compared to their matched nonusers. We concluded that there were no statistical associations between different types of antiarrhvthmic drug usage and subsequent PCa risk.

关键词： antiarrhythmic drugs cancer digoxin ion channel blocker prostate cancer

North Celestial Region Observed with 21 CentiMeter Array

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Research in Astronomy and Astrophysics 2022年第1期22卷 126-136页

作者： Bi-Xuan Zhao Qian Zheng huan-yuan Shan Quan Guo Kuan-Jun Li Shanghai Astronomical Observatory Chinese Academy of Sciences80 Nandan RoadShanghai 200030China National Astronomical Observatory Chinese Academy of Sciences20 Datun RoadBeijing 100101China

The 21 CentiMeter Array(21 CMA) is a radio interferometer in western China. The key science objective of21 CMA is statistically measuring the redshifted H I 21 cm signal of the Epoch of Reionization(EoR). In order to achieve this, a catalog of radio sources is necessary for both calibration and foreground removal. In this work, we present a catalog of 832 radio sources within a radius of 5° around the North Celestial Pole region observed with21 CMA. Three days of data taken in 2013 are used in the analysis, with a frequency coverage from 75 to 200 MHz and an angular resolution of about two arcminutes at 200 MHz. Flux densities and estimated spectral indices of the radio sources are provided in the source catalog. For simplicity, only the east–west baseline is used for the observations to avoid the so-called w-term in the data analysis. The longest baseline along the east–west direction is 2780 m. Comparing our source counts with other radio observations, we find a good agreement with the observations made with the Giant Metrewave Radio Telescope and Murchison Widefield Array. Our data reduction is still limited by grating lobes of very bright sources in the field due to the redundant configuration of21 CMA. We note that understanding the properties of radio sources, and modeling and removing the radio sources are challenges for the EoR experiments.

关键词： radio continuum:general instrumentation:interferometers radio continuum:galaxies methods:observational