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Environmental mercury exposure, semen quality and reproductive hormones in Greenlandic Inuit and European men： a cross-sectional study

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Asian Journal of Andrology 2013年第1期15卷 97-104页

作者： Emina Mocevic Ina O Specht Jacob L Marott Aleksander Giwercman bo ag jonsson Gunnar Toft Thomas Lundh Jens Peter bonde Department of Occupational and Environmental Medicine Copenhagen University Hospital Bispebjerg Copenhagen NV DK-2400 Denmark Reproductive Medicine Centre Sk~ne University Hospital Malm6 Lund University Malm6 SE-20502 Sweden Division of Occupational and Environmental Medicine Department of Laboratory Medicine Lund University Lund SE-22185 Sweden Department of Occupational Medicine Aarhus University Hospital Aarhus DK-8000 Denmark

Several animal studies indicate that mercury is a male reproductive toxicant, but human studies are few and contradictory. We examined semen characteristics and serum levels of reproductive hormones in relation to environmental exposure to mercury. Blood and semen samples were collected from 529 male partners of pregnant women living in Greenland, Poland and Ukraine between May 2002 and February 2004. The median concentration of the total content of mercury in whole blood was 9.2 ng ml-1 in Greenland （0.2- 385.8 ng ml-1）, 1.0 ng m1-1 in Poland （0.2-6.4 ng ml-z） and 1.0 ng ml-I in Ukraine （0.2-4.9 ng ml-1）. We found a significantly positive association between the blood levels of mercury and serum concentration of inhibin B in men from Greenland （p=0.074, 95% confidence interval （CI）=0.021 to 0.126） and in an analysis including men from all three regions （p=0.067, 95% C1=0.024 to O. 110）. The association may be due to beneficial effects of polyunsaturated fatty acids （PUFAs）, which are contained in seafood and fish. No significant association （P〉O.05） was found between blood concentrations of mercury and any of the other measured semen characteristics （semen volume, total sperm count, sperm concentration, morphology and motility） and reproductive hormones （free androgen index {FAI）, follicle-stimulating hormone （FSH）, luteinizing hormone （LH）, testosterone and LH xtestosterone） in any region. In conclusion, the findings do not provide evidence that environmental mercury exposure in Greenlandic and European men with median whole blood concentration up to 10 ng m1^-1 has adverse effects on biomarkers of male reproductive health.

关键词： blood mercury concentration environmental mercury exposure male fertility reproduction reproductive hormones semen characteristics semen quality

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Enhancing thermoelectric performance in P-type Mg_(3)Sb_(2)-based Zintls through optimization of band gap structure and nanostructuring

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Journal of Materials Science & Technology 2024年第3期170卷 25-32页

作者： Yi-bo Zhang Ji-Sheng Liang Chengyan Liu Qi Zhou Zhe Xu Hong-bo Chen Fu-cong Li Ying Peng Lei Miao Guangxi Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesMinistry of EducationSchool of Material Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory for Relativity Astrophysics Center on Nanoenergy ResearchGuangxi Key Laboratory of Processing for Nonferrous Metal and Featured MaterialsSchool of Physical Science&TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Precision Navigation Technology and Application Guilin University of Electronic TechnologySchool of Information and CommunicationGuilin 541004China

P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low ***,compared to their n-type counterparts,they show relatively low TE performance,limiting their application in TE *** this work,we simultaneously introduce Bi alloying at Sb sites and ag doping at Mg sites into the Mg_(3)Sb_(2)to coopera-tively optimize the electrical and thermal properties for the first time,acquiring the highest ZT value of∼0.85 at 723 K and a high average ZT of 0.39 in the temperature range of 323-723 K in sample Mg_(2.94)ag_(0.06)Sb_(1.9)Bi_(0.1).The first-principle calculations show that the codoping of ag and Bi can shift the Fermi level into the valence band and narrow the band gap,resulting in the increased carrier concentration from 3.50×10^(17)cm^(-3)in the reference Mg 3 Sb 0.9 Bi 0.1 to∼7.88×10^(19)cm^(-3)in sample Mg 2.94 ag 0.06 Sb 0.9 Bi *** a result,a remarkable power factor of∼778.9μW m^(-1)K^(-2)at 723 K is achieved in sample Mg 2.94 ag 0.06 Sb 0.9 Bi ***,a low lattice thermal conductivity of∼0.48 W m^(-1)K^(-1)at 723 K is also obtained with the help of phonon scattering at the distorted lattice,point defects,and nano-precipitates in sample Mg 2.94 ag 0.06 Sb 0.9 Bi *** synergistic effect of using the multi-element co-doping/-alloying to optimize electrical properties in Mg_(3)Sb_(2)holds promise for further improving the TE performance of Zintl phase materials or even others.

关键词： Thermoelectric materials Band engineering Nanostructuring P-type Mg_(3)Sb_(2) ag and Bi Co-doping

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Optimal Planning of Hybrid AC/DC Low-voltage Distribution Networks Considering DC Conversion of Three-phase Four-wire Low-voltage AC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 141-153页

作者： bo Zhang Lu Zhang Wei Tang Gen Li Chen Wang the College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China the Electric Energy Group Department of Engineering TechnologyTechnical University of Denmark(DTU)2750 BallerupDenmark the Power Distribution Technology Center State Grid Beijing Electric Power Research InstituteBeijing 100075China

The increasing integration of distributed household photovoltaics(PVs)and electric vehicles(EVs)may further ag gravate voltage violations and unbalance of low-voltage distribu tion networks(LVDNs).DC distribution networks can increase the accommodation of PVs and EVs and mitigate mutilple pow er quality problems by the flexible power regulation capability of voltage source *** paper proposes schemes to es tablish hybrid AC/DC LVDNs considering the conversion of the existing three-phase four-wire low-voltage AC systems to DC op *** characteristics and DC conversion constraints of typical LVDNs are *** addition,converter configura tions for typical LVDNs are proposed based on the three-phase four-wire characteristics and quantitative analysis of various DC ***,an optimal planning method of hybrid AC/DC LVDNs is proposed,which is modeled as a bi-level programming model considering the annual investments and three-phase *** are conducted to verify the effectiveness of the proposed optimal planning *** ulation results show that the proposed optimal planning method can increase the integration of PVs while simultaneously reduc ing issues related to voltage violation and unbalance.

关键词： Optimal planning low-voltage distribution net work three-phase unbalance DC conversion

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Positron Emission Tomography Lung Image Respiratory Motion Correcting with Equivariant Transformer

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Computers, Materials & Continua 2024年第5期79卷 3355-3372页

作者： Jianfeng He Haowei Ye Jie Ning Hui Zhou bo She Faculty of Information Engineering and Automation Kunming University of Science and TechnologyYunnan Key Laboratory of Artificial IntelligenceKunming650500China School of Physics and Electronic Engineering Yuxi Normal UniversityYuxi653100China PET/CT Center Affiliated Hospital of Kunming University of Science and TechnologyFirst People’s Hospital of Yunnan ProvinceKunming650031China

In addressing the challenge of motion artifacts in Positron Emission Tomography (PET) lung scans, our studyintroduces the Triple Equivariant Motion Transformer (TEMT), an innovative, unsupervised, deep-learningbasedframework for efficient respiratory motion correction in PET imaging. Unlike traditional techniques,which segment PET data into bins throughout a respiratory cycle and often face issues such as inefficiency andoveremphasis on certain artifacts, TEMT employs Convolutional Neural Networks (CNNs) for effective featureextraction and motion ***’s unique approach involves transforming motion sequences into Liegroup domains to highlight fundamental motion patterns, coupled with employing competitive weighting forprecise target deformation field generation. Our empirical evaluations confirm TEMT’s superior performancein handling diverse PET lung datasets compared to existing image registration networks. Experimental resultsdemonstrate that TEMT achieved Dice indices of 91.40%, 85.41%, 79.78%, and 72.16% on simulated geometricphantom data, lung voxel phantom data, cardiopulmonary voxel phantom data, and clinical data, respectively. Tofacilitate further research and practical application, the TEMT framework, along with its implementation detailsand part of the simulation data, is made publicly accessible at https://***/yehaowei/temt.

关键词： PET lung scans respiratory motion correction triple equivariant motion transformer lie group motion decomposition

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Effect of Plastic Deformation on Microstructure and Properties of Cu-(1 wt%-6 wt%) ag Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 747-753页

作者：茹亚东 ZHANG Zhongyuan 高召顺 ZHANG Ling ZUO Tingting XUE Jiangli TANG Zhixiang DA bo LIU Yongsheng XIAO Liye Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China Department of Physics Shanghai University of Electric PowerShanghai 201306China University of Chinese Academy of Sciences Beijing 100190China International Joint Labora-tory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Research and Services Division of Materials Data and Integrated System National Institute for Materials ScienceTsukuba 305-0047Japan

In the present study,the Cu-(1 wt%-6 wt%)ag alloys were prepared by melting,forging and wire *** effects of plastic deformation on microstructure evolution and properties of the alloys were *** results show that non-equilibrium eutectic colonies exist in the Cu-(3 wt%-6 wt%)ag alloy and no eutectic colonies in the 1 wt%-2 wt%ag containing *** eutectic colonies are aligned along the drawing direction and refined with the increase of draw *** to the refinement of eutectic colonies,the Cu-ag alloy exhibits higher strength with the increase of draw *** Cu-6ag alloy exhibits excellent comprehensive properties with a strength of 930 MPa and a conductivity of 82%IACS when the draw ratio reaches 5.7.

关键词： Cu-ag alloy high strength and high conductivity microstructure eutectic structure strengthening mechanism

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Albizzia chinensis(Osbeck)Merr extract YS ameliorates ethanol-induced acute gastric ulcer injury in rats by regulating NRF2 signaling pathway

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Animal Models and Experimental Medicine 2024年第3期7卷 275-282页

作者： bo Tang Liangning Li Yuanzhi Yu Guibin Wang Shuanggang Ma Shishan Yu Jianjun Zhang Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina State Key Laboratory of Digestive Health BeijingChina State Key Laboratory of Bioactive Substance and Function of Natural Medicines BeijingChina

Background:Around the world,there is a high incidence of gastric ***,an extract from the Chinese herb Albizzia chinensis(Osbeck)Merr,has potential therapeutic applications for gastrointestinal *** we elucidated the protective effect and underlying mechanism of action of YS on gastric ulcer in rats injured by ***:The ethanol-i nduced gastric ulcer rat model was used to assess the protective effect of YS.A pathological examination of gastric tissue was performed by H&E ***-1 cells damaged by hydrogen peroxide were used to simulate oxidative damage in gastric mucosal epithelial *** NRF2 was knocked down using small interfering *** was used to detect ubiquitination of ***-i mmunoprecipitation was used to detect the NRF2-Keap1 ***:YS(10 and 30 mg/kg,i.g.)significantly reduced the ulcer index,decreased MDA level,and increased SOD and GSH levels in gastric tissues damaged by *** promoted NRF2 translocation from cytoplasm to nucleus and enhanced the NQO1 and HO-1 expression levels in injured rat gastric *** addition,YS regulated NQO1 and HO-1 via NRF2 in H_(2)O_(2)-i nduced oxidative injured GES-1 *** studies on the underlying mechanism indicated that YS reduced the interaction between NRF2 and Keap1 and decreased ubiquitylation of NRF2,thereby increasing its stability and expression of downstream ***2 knockdown abolished the effect of YS on MDA and SOD in GES-1 cells treated with H_(2)O_(2).Conclusion:YS reduced the NRF2-Keap1 interaction,promoting NRF2 translocation into the nucleus,which increasing the transcription and translation of NQO1 and HO-1 and improved the antioxidant capacity of rat stomach.

关键词： antioxidative ethanol gastric ulcer NRF2 YS

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SnS_(2) nanosheets decorated SnO_(2) hollow multishelled nanostructures for enhanced sensing of triethylamine gas

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Rare Metals 2024年第5期43卷 2339-2348页

作者： Wen-Di Liu Ya Xiong Ao Shen Xin-Zhen Wang Xiao Chang Wen-bo Lu Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China College of Physics Qingdao UniversityQingdao 266071China Zernike Institute for Advanced Materials University of Groningen9747 AG GroningenThe Netherlands

Highly sensitive,fast and low-temperature detection of triethylamine(TEA)gas based on SnO_(2) is attractive yet remains ***,SnS_(2) nanosheets(NSs)/SnO_(2) hollow multishelled structures(HoMSs)-based sensors are designed by the synthesis of SnO_(2) HoMSs,followed by in situ sulfuration with *** varying the thioacetamide levels,Sn S_(2)/SnO_(2) heterostructures with different SnS_(2) contents were obtained and their TEA gas sensing performances were investigated.

关键词： SnS attractive sheets

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Effects of Ta content on microstructure and oxidation behavior of AlCoCrFeNiYTax high entropy alloy

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Rare Metals 2024年第9期43卷 4462-4475页

作者： Cang Gu Jun-Hao Hu Jian-bo Song Cheng Xu Ming-Yu Hu Yu-Xuan Zhang Jiang Tian Chao Li Jing Feng Faculty of Materials Science and Engineering Kunming University of Science and Technology Department of Physics Hong Kong Baptist University

The oxidation behavior of the Al Co Cr Fe Ni YTaxhigh entropy alloy（HEA） doped with different Ta contents at 1100 °C is investigated. In this study, different reasons for the spallation of the oxide scales of HEAs without/with excessive Ta addition after 1000 h of oxidation are discussed, and the most suitable Ta doping content for this HEA is explored, in which the HEA exhibits both an exceptionally low oxidation rate, and the formation of oxide scales composed of intact a-Al2O3. Meanwhile, it is found that the addition of Ta can effectively inhibit the phase transition of β phase, which makes the surface of the oxide scale smoother. By combining our experimental results with Wagner–Hauffe theory, the influence of Ta drag effect on oxide scale growth is explained, which provides some theoretical guidance for the subsequent design of Al Co Cr Fe Ni HEAs, and can lead to the development of thermal barrier coatings at higher service temperature.

关键词： Al2O3 scales Elements diffusion High-entropy alloy Oxidation

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CNT array-induced nanobubble assembly,nanodisk fabrication and enhanced spectral detection of CNT bundle density

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Nano Research 2024年第8期17卷 7737-7745页

作者： Zhiyuan Xia Ziming Ye bo Zhao Tingsong Zhang Qi Wang Kun Chen Meng Li Xiaobing Kong Yu-Qing Zheng Enzheng Shi Yuanyuan Shang Anyuan Cao School of Materials Science and Engineering Peking UniversityBeijing 100871China School of Integrated Circuits Peking UniversityBeijing 100871China School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China School of Engineering Westlake UniversityHangzhou 310024China

Alignment,functionalization and detection of carbon nanotube(CNT)bundles are vital processes for utilizing this onedimensional nanomaterial in ***,we report a polymer-assisted wet shearing method to acquire super-aligned craterpatterned CNT arrays by nanobubble(NB)self-assembly with a"migrate and aggregation"mechanism and use craters to controllably mold even-sized nanodisks periodically along CNT bundles with tunable *** green,low-cost method can be extended to diverse substrates and fabricate different *** an example,the ag-nanodisk-patterned CNT arrays are utilized as substrates of surface-enhanced Raman scattering(SERS)for rhodamine 6G(R6G)and methylene blue(MB)in which a linear correlation is found between the SERS intensity and the CNT bundle density due to the periodic distribution of hot spots,enabling a spectral detection of CNT bundles and their densities by conventional dye *** from routine morphological characterization,this spectral method possesses an enhanced accuracy and a detection range of 0.1–2μm^(–1),showing its uniqueness in the detection of CNT bundle density since the intensity of traditional spectral merely relates to the quantity of CNTs,exhibiting its potential in future CNT-bundle-based electronics.

关键词： CNT arrays nanobubbles self-assembly nanodisks surface-enhanced Raman scattering(SERS)

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滇中老街子Pb-ag矿床稀土元素富集特征及其赋存状态

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中国稀土学报 2024年第3期42卷 591-602页

作者：王博吴鹏杨航昆明理工大学国土资源工程学院云南昆明650221

滇中姚安铅多金属矿床是金沙江-红河富碱斑岩多金属成矿带的典型代表,带内铅多金属矿床中出现稀土矿化富集的现象鲜有报道。近年来,在姚安老街子Pb-ag矿床发现稀土元素超常富集,部分地段含量已超过工业品位,形成矿(化)体。稀土与铅多金... 详细信息

滇中姚安铅多金属矿床是金沙江-红河富碱斑岩多金属成矿带的典型代表,带内铅多金属矿床中出现稀土矿化富集的现象鲜有报道。近年来,在姚安老街子Pb-ag矿床发现稀土元素超常富集,部分地段含量已超过工业品位,形成矿(化)体。稀土与铅多金属同空间矿化富集现象引发该类矿床成矿作用研究的问题:稀土元素富集特征及其赋存状态如何?本文系统采集2108,2073,2038,2003 m中段坑道中富碱斑岩样品231件,采用ICP-MS测定稀土元素含量,并绘制其异常分布图,总结稀土元素空间富集规律。研究发现在垂向空间上由浅及深,稀土元素含量呈现递增趋势。通过电子探针分析,识别出独居石、褐帘石等稀土矿物。综合对宏观空间尺度稀土元素的富集特征以及微观尺度稀土赋存状态的研究,认为稀土富集与北东-近东西向断裂、黄铁矿化、方铅矿化在空间上关系密切,该矿床稀土具有成矿潜力与找矿前景。

关键词：稀土元素富集特征赋存状态老街子Pb-ag矿床滇中

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