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Gradient nanostructured tungsten and the thermal shock response

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Tungsten 2023年第4期5卷 548-557页

作者： Yan jiang Ping Huang Zhi-Qiang jiang Jing Hou Zhong Xu En-Hui Wu Jun li Vanadium and Titanium Resource Comprehensive Utilization Key Laboratory of Sichuan Province Panzhihua UniversityPanzhihua617000China

In fusion reactor or spallation neutron source environment,damage of tungsten components begins at the *** enhance the surface toughness,strength,and hardness of tungsten,a nano-to-micro sc ale lamellar gradient surface layer(thickness up to~50μm)was produced on as-rolled pure tungsten using a dry-sliding surface *** dry-sliding temperature and time were established by observing the grain-size evolution from room temperature to 750℃and the coefficient of friction on the surface layer after sliding from 10 to 50 *** grains changed into a slender fibrous structure at 250℃,which is higher than the ductile-brittle transition temperature but lower than the dynamic recrystallization temperature(750℃).The coefficient of friction of the surface layer decreased with sliding time and stabilized at approximately 50 min,indicating near-s aturation of the surface *** repetitive thermal loads of 10,20,and 30 MW·m^(-2)on the gradient modified layer,it exhibited mainly recrystallization and grain *** proportion of low-angle grain boundaries(lization and grain growth are relatively ***,the gradient layer could suppress the formation of pits and protrusions in the as-rolled tungsten sample.

关键词： Gradient layer Tungsten Dry sliding Coefficient of friction

Calculation of the Ground States of H^(-) Ion and He Atom in Magnetic Field with a Modified Configuration Interaction Method

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Chinese Physics Letters 1999年第2期16卷 101-103页

作者： QIAO Hao-xue RAO jian-guo li Bai-wen Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071

The modified configuration interaction method is extended to double electronic systems in magnetic ***-values and binding energies of ground state of H^(-) ion and He atom in uniform magnetic fields are *** a range running from low to intermediate magnetic fields,the best results with relative errors of 1.0×10^(-5) and 1.4×10^(-6) for H^(-) and He,respectively,are *** accuracy of our results are almost 2 orders of magnitude better than those obtained by the other methods.

关键词： methods. Configuration Modified

The virulence regulator AbsR in avian pathogenic Escherichia coli has pleiotropic effects on bacterial physiology

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Journal of Integrative Agriculture 2024年第2期23卷 649-668页

作者： Dongfang Zhao Haobo Zhang Xinyang Zhang Fengwei jiang Yijing li Wentong Cai Ganwu li State Key Laboratory for Animal Disease Control and Prevention Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069China College of Veterinary Medicine Northeast Agricultural UniversityHarbin 150038China National Animal Tuberculosis Reference Laboratory Division of Zoonoses SurveillanceChina Animal Health and Epidemiology CenterQingdao 266032China Department of Veterinary Diagnostic and Production Animal Medicine College of Veterinary MedicineIowa State UniversityAmesIowa 50011-1134the United States

Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic ***(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and ***(microcin production regulation,locus A,herein renamed AbsR,a blood survival regulator),a member of the MarR(multiple antibiotic resistance regulator)transcriptional regulator family,governs the expression of capsule biosynthetic genes in human ExPEC and represents a promising druggable target for ***,a deep understanding of the AbsR regulatory mechanism as well as its regulon is *** this study,we present a systems-level analysis of the APEC AbsR regulon using ChIP-Seq(chromatin immunoprecipitation sequencing)and RNA-Seq(RNA sequencing)*** found that AbsR directly regulates 99 genes and indirectly regulates 667 ***,we showed that:1)AbsR contributes to antiphagocytotic effects by macrophages and virulence in a mouse model for systemic infection by directly activating the capsular gene cluster;2)AbsR positively impacts biofilm formation via direct regulation of the T2SS(type II secretion system)but plays a marginal role in virulence;and 3)AbsR directly upregulates the acid tolerance signaling system EvgAS to withstand acid stress but is dispensable in ExPEC ***,our data indicate that the role of AbsR in virulence gene regulation is relatively conserved in ExPEC ***,this study provides a comprehensive analysis of the AbsR regulon and regulatory mechanism,and our data suggest that AbsR likely influences virulence primarily through the control of capsule ***,we found that AbsR severely represses the expression of the type I-F CRISPR(clustered regularly interspaced short palindromic repeats)-Cas(CRISPR associated)systems,which could have implications in CRISPR biology and application.

关键词： avian pathogenic Escherichia coli(APEC) extraintestinal pathogenic Escherichia coli(ExPEC) AbsR RNA-Seq ChIP-Seq gene regulation

The dynamical architecture and habitable zones of the quintuplet planetary system 55 Cancri

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Research in Astronomy and Astrophysics 2009年第6期9卷 703-711页

作者： jiang-Hui Ji Hiroshi Kinoshita lin liu Guang-Yu li Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China National Astronomical Observatory Mitaka Tokyo 181--8588 Japan Department of Astronomy Nanjing University Nanjing 210093 China

We perform numerical simulations to study the secular orbital evolution and dynamical structure of the quintuplet planetary system 55 Cancri with the self-consistent orbital solutions by Fischer and coworkers. In the simulations, we show that this system can be stable for at least 108 yr. In addition, we extensively investigate the planetary configuration of four outer companions with one terrestrial planet in the wide region of 0.790AU 〈 a 〈 5.900AU to examine the existence of potential asteroid structure and Habitable Zones （HZs）. We show that there are unstable regions for orbits about 4：1, 3：1 and 5：2 mean motion resonances （MMRs） of the outermost planet in the system, and several stable orbits can remain at 3：2 and 1：1 MMRs, which resembles the asteroid belt in the solar system. From a dynamical viewpoint, proper HZ candidates for the existence of more potential terrestrial planets reside in the wide area between 1.0 AU and 2.3 AU with relatively low eccentricities.

关键词： celestial mechanics -- methods n-body simulations -- planetary systems -- stars individual (55 Cancri)

Amphibian Species Contribute Similarly to Taxonomic, but not Functional and Phylogenetic Diversity: Inferences from Amphibian Biodiversity on Emei Mountain

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Asian Herpetological Research 2018年第2期9卷 110-118页

作者： Tian ZHAO Bin WANG Guocheng SHU Cheng li jianping jiang CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of Biology Chinese Academy of Sciences

Understanding the relationships between species, communities, and biodiversity are important challenges in conservation ecology. Current biodiversity conservation activities usually focus on species that are rare, endemic, distinctive, or at risk of extinction. However, empirical studies of whether such species contribute more to aspects of biodiversity than common species are still relatively rare. The aim of the present study was to assess the contribution of individual amphibian species to different facets of biodiversity, and to test whether species of conservation interest contribute more to taxonomic, functional, and phylogenetic diversity than do species without special conservation status. To answer these questions, 19 000 simulated random communities with a gradient of species richness were created by shuffling the regional pool of species inhabiting Emei Mountain. Differences of diversity values were then computed before and after removing individual species in these random communities. Our results indicated that although individual species contributed similarly to taxonomic diversity, their contribution to functional and phylogenetic diversity was more idiosyncratic. This was primarily driven by the diverse functional attributes of species and the differences in phylogenetic relationships among species. Additionally, species of conservation interest did not show a significantly higher contribution to any facet of biodiversity. Our results support the claims that the usefulness of metrics based only on species richness is limited. Instead, assemblages that include species with functional and phylogenetic diversity should be protected to maintain biodiversity.

关键词： amphibians conservation taxonomic diversity functional diversity phylogenetic diversity

Determinants of vigilance in a reintroduced population of Pere David＇s deer

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Current Zoology 2013年第2期59卷 265-270页

作者： Wei ZHENG Guy BEAUCHAMP Xuelei jiang Zhongqiu li Qinglong YANG The State Key Laboratory of Pharmaceutical B iotechnology School of Life Science Nanjing University Nanjing 210093 China Faculty of Veterinary Medicine University of Montreal St-Hyacinthe Quebec Canada J2S 7C6 Jinling College Nanjing University Nanjing 210089 China

After being kept in captivity and isolated from natural predators for more than 1,200 years, P6re David＇s deer has been reintroduced in China and now occurs in a reserve where human activity is the only potential threat. Antipredator vigilance i~ an important component of survival for many prey animals in their natural habitat. Do deer still adjust vigilance as a function of risk after such a long period of relaxed predation pressure？ Here, we examined vigilance levels in P6re David＇s deer groups as a function of group size, sex and level of human disturbance. The results showed that individual vigilance significantly decreased with group size in all-female groups but not in all-males or mixed-sex groups. In rutting season, males compete with one another and harass females, and we argue that vigilance is partly aimed at threatening males and that such vigilance increases with group size. This explains why overall vigilance did not vary with group size for males in general and for females in mixed-sex groups. Vigilance increased in more disturbed areas but in in male deer only. The results indicate that despite relaxed predation pressure over centuries, P6re David＇s deer can still adjust antipredator responses as a function of perceived risk. Such information may become useful in the rewilding programme now under way for this species in China [Current Zoology 59 （2）： 265-270, 2013].

关键词： Antipredator vigilance Group size Human disturbance Sexual competition P6re David's deer

Criterion for Genuine Multipartite Entanglement Quantum Channels

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Chinese Physics Letters 2010年第1期27卷 13-16页

作者：姜年权王育建 College of Physics and Electric Information Wenzhou University Wenzhou 325035

We introduce a character matrix for the N-qubit subsystem of a 2N-qubit state and show the criterion for genuine entanglement channel existing between two N-qubit subsystems in the state. The criterion allows us to check conveniently whether genuine quantum channels exist or not in the 2N-qubit state without calculating its N-qubit reduced density matrices.

关键词： Criterion Multipartite Quantum

An association study of HFEgene mutation with idiopathic male infertility in the Chinese Han population

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Asian Journal of Andrology 2012年第4期14卷 599-603页

作者： Xiao-Ying Yu Bin-Bin Wang Zhong-Cheng Xin Tao liu Ke Ma jian jiang Xiang Fang li-Hua Yu Yi-Feng Peng Xu Ma Institute of Reproductive Medicine Yijishan HospitalWannan Medical CollegeWuhu 241001China National Research Institute for Family Planning Beijing 100081China peking Union Medical College Beijing 100081China Andrology Center Peking University First HospitalBeijing 100034China World Health Organization Collaborating Centre for Research in Human Reproduction Beijing 100081China

Mutations in the haemochromatosis gene （HFE） influence iron status in the general population of Northern Europe, and excess iron is associated with the impairment of spermatogenesis. The aim of this study is to investigate the association between three mutations （C282Y, H63D and S65C） in the HFEgene with idiopathic male infertility in the Chinese Han population. Two groups of Chinese men were recruited： 444 infertile men （including 169 with idiopathic azoospermia） and 423 controls with proven fertility. The HFEgene was detected using polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） technique. The experimental results demonstrated that no C282Y or $65C mutations were detected. Idiopathic male infertility was not significantly associated with heterozygous H63D mutation （odds ratio=O.801, 95% confidence interval=0.452-1.421, X2=0.577, P=0.448）. The H63D mutation frequency did not correlate significantly with the serum luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and testosterone （T） levels in infertile men （P=0.896, P=0.404 and P=O.05, respectively）. Our data suggest that the HFEH63D mutation is not associated with idiopathic male reproductive dysfunction.

关键词： gene mutation gonadotropic hormone HFE male infertility

A novel fine-resolution snow depth retrieval model to revealdetailed spatiotemporal patterns of snow cover in NortheastChina

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International Journal of Digital Earth 2023年第1期16卷 1164-1185页

作者： Yanlin Wei Xiaofeng li lingjia Gu Xingming Zheng Tao jiang Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchunPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Changchun Jingyuetan Remote Sensing Experiment Site Chinese Academy of SciencesChangchunPeople’s Republic of China College of Electronic Science&Engineering Jilin UniversityChangchunPeople’s Republic of China

Seasonal snow cover is a key component of the global climate and hydrological system,it has drawn considerable attention under global warming *** several passive microwave(PMW)snow depth(SD)products have been developed since the 1970s,they inherit noticeable errors and uncertainties when representing spatial distributions and temporal changes of SD,especially in complex mountainous *** this paper,we developed afine-resolution SD retrieval model(FSDM)using machine learning to improve SD estimation quality for Northeast China and produced a long-term,fine-resolution,daily SD *** accuracies of the FSDM dataset were evaluated against in-situ SD data along with existing SD *** results showed the FSDM dataset provided satisfactory inversion accuracy in spatiotemporal evaluation,with the root-mean-square error(RMSE),bias,and correlation coefficient(R)of 7.10 cm,-0.13 cm,and ***,we analyzed the spatiotemporal variations of SD in Northeast China and found that snow cover was mainly distributed in the Greater Khingan Range,Lesser Khingan Mountains,and Changbai Mountain *** SD exhibited high-low distribution patterns with the increased *** annual mean SD slightly increased at the rate of 0.029 cm/year during 1987-2018.

关键词： Passive microwave remote sensing snow depth inversion machine learning fine resolution Northeast China