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Health risk assessment of heavy metals in soils and crops in a mining area(Au-Ag-Cutrona-oil et al.) of the Nanyang Basin, Henan Province, China

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China Geology 2023年第4期6卷 567-579页

作者： Qiu-yao Dong hao-tian wen Pan Wang Chao Song Shu-ya Lai Zhen-jing Yang Yuan-yi Zhao Ming-jiang Yan Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Quaternary Chronology and Hydro-Environmental Evolution China Geological SurveyMinistry of Natural ResourcesShijiazhuang 050061China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences Hebei GEO UniversityShijiazhuang 050031China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China

Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound *** root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dom

关键词： Heavy metal Zn-Cd-Pb pollution Cr-Ni pollution As pollution Natural ecosystem Health risk assessment Adult-children health risk Ecological risk index(ERI) Ecological geological engineering Mining activity

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High Resolution Microwave B-Field Imaging Using a Micrometer-Sized Diamond Sensor

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Chinese Physics Letters 2019年第12期36卷 70-73页

作者： wen-hao He Ming-Ming Dong Zhen-Zhong Hu Qi-Han Zhang Bo Yang Ying Liu Xiao-Long Fan Guan-Xiang Du College of Telecommunication&Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210000 School of Physical Science and Technology Lanzhou UniversityLanzhou 730000

We propose a diamond-based micron-scale sensor and perform high-resolution B-field imaging of the near-field distribution of coplanar *** sensor consists of diamond crystals attached to the tip of a tapered fiber with a physical size on the order of *** amplitude of the B-field component B is obtained by measuring the Rabi oscillation *** result of Rabi sequence is fitted with a decayed *** apply the modulation-locking technique that demonstrates the vector-resolved field mapping of the micromachine coplanar waveguide structure(CPW).B-field line scan was performed on the CPW with a scan step size of 1.25μ*** demonstrate vector resolved rf field sensing,a full field line scan acts(was performed)along four NV axes at a height of 50μm above the device *** simulations are compared with the experimental results by vector-resolved *** technique allows the measurement of weak microwave signals with a minimum resolvable modulation depth of 20 *** sensor will have great interest in micron-scale resolved microwave B-field measurements,such as electromagnetic compatibility testing of microwave integrated circuits and characterization of integrated microwave components.

关键词： microwave resolved Diamond

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虹膜识别算法的研究

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哈尔滨工程大学学报 2006年第3期27卷 400-403,452页

作者：孟浩徐翠平哈尔滨工程大学自动化学院黑龙江哈尔滨150001

虹膜识别是一种非常可靠的身份鉴别方法.在讨论虹膜图像定位、增强等预处理方法的基础上,针对现有虹膜识别算法中存在的问题,提出了虹膜有效区域选择、特征提取及编码匹配的有效方法.在虹膜图像有效区域的选择上,根据虹膜图像自身的生... 详细信息

虹膜识别是一种非常可靠的身份鉴别方法.在讨论虹膜图像定位、增强等预处理方法的基础上,针对现有虹膜识别算法中存在的问题,提出了虹膜有效区域选择、特征提取及编码匹配的有效方法.在虹膜图像有效区域的选择上,根据虹膜图像自身的生物特点采用一种新的分割方法,使得到的图像纹理信息更充足;在图像的特征提取方面,采用Gabor小波变换,将频率分为2个频段,不同的频段选择不同Gabor尺度参数,并选择适当的位置参数;为解决虹膜图像的旋转对虹膜识别的影响,将获得的虹膜编码进行错位匹配.实验结果表明,所提出的虹膜识别算法效果较好.

关键词：虹膜纹理旋转有效区域选择Gabor小波特征提取

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表面活性剂对油溶性降黏剂降黏效果的影响及作用机制

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中国石油大学学报（自然科学版） 2013年第3期37卷 161-166页

作者：崔敏李传文萍邓文安中国石油大学理学院山东青岛266580 中国石油大学重质油国家重点实验室山东青岛266580

以轮古稠油为原料,考察十六烷基三甲基溴化铵(CTAB)、十二烷基磺酸钠(SDS)和OP-10(OP)对自制的油溶性降黏剂马来酸酐-苯乙烯-丙烯酸十八醇酯共聚物(MSA)降黏效果的影响;通过相对黏度法和质量分数电导率法,从沥青质缔合性和稠油胶体稳定... 详细信息

以轮古稠油为原料,考察十六烷基三甲基溴化铵(CTAB)、十二烷基磺酸钠(SDS)和OP-10(OP)对自制的油溶性降黏剂马来酸酐-苯乙烯-丙烯酸十八醇酯共聚物(MSA)降黏效果的影响;通过相对黏度法和质量分数电导率法,从沥青质缔合性和稠油胶体稳定性两个方面分析表面活性剂在稠油降黏过程中的作用机制。结果表明:1%的MSA能使稠油黏度从6.720 Pa·s下降到2.810 Pa·s,同时使稠油沥青质的缔合度减小,稠油胶体稳定性增强;CTAB、SDS和OP的加入均能继续提高MSA的降黏效果,其作用效果顺序为CTAB>SDS>OP;SDS和OP能促进MSA对沥青质的解缔作用,使沥青质缔合度继续减小,而CTAB不具备促进MSA解缔沥青质的能力;CTAB、SDS和OP均能促进MSA增强稠油胶体稳定性,其作用效果顺序为CTAB>SDS>OP,这与3种表面活性剂增强MSA降黏效果的能力顺序一致;对于轮古稠油,相对于稠油沥青质的缔合性,体系胶体稳定性是影响MSA降黏效果的主要因素。

关键词：表面活性剂油溶性降黏剂沥青质缔合性胶体稳定性机制

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MdbHLH3 modulates apple soluble sugar content by activating phosphofructokinase gene expression

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Journal of Integrative Plant Biology 2022年第4期64卷 884-900页

作者： Jian-Qiang Yu Kai-Di Gu Li-Li Zhang cui-Hui Sun Quan-Yan Zhang Jia-Hui Wang Chu-Kun Wang wen-Yan Wang Meng-Chi Du Da-Gang Hu National Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'an 271018China College of Resources and Environment Linyi UniversityLinyi 276005China MOA Key Laboratory of Horticultural Crop Biology and Germplasm Innovation Tai'an 271018China Shandong Collaborative Innovation Center for Fruit and Vegetable Production with High Quality and Efficiency Tai'an 271018China

Sugars are involved in plant growth,fruit quality,and signaling ***,understanding the mechanisms involved in soluble sugar accumulation is essential to understand fruit ***,we report that Md PFPβ,a pyrophosphatedependent phosphofructokinase gene,regulates soluble sugar accumulation by enhancing the photosynthetic performance and sugar-metabolizing enzyme activities in apple(Malus domestica Borkh.).Biochemical analysis revealed that a basic helix-loop-helix(b HLH)transcription factor,Mdb HLH3,binds to the Md PFPβpromoter and activates its expression,thus promoting soluble sugar accumulation in apple *** addition,Md PFPβoverexpression in tomato influenced photosynthesis and carbon metabolism in the ***,we determined that Mdb HLH3 increases photosynthetic rates and soluble sugar accumulation in apple by activating Md PFPβ*** results thus shed light on the mechanism of soluble sugar accumulation in apple leaves and fruit:Mdb HLH3 regulates soluble sugar accumulation by activating Md PFPβgene expression and coordinating carbohydrate allocation.

关键词： apple bHLH fructose 6-phosphate fruit quality phosphofructokinase soluble sugars

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Rosmarinic acid ameliorates hypoxia/ischemia induced cognitive deficits and promotes remyelination

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Neural Regeneration Research 2020年第5期15卷 894-902页

作者： Man Li Miao-Miao cui Nwobodo Alexander Kenechukwu Yi-Wei Gu Yu-Lin Chen Si-Jing Zhong Yu-Ting Gao Xue-Yan Cao Li Wang Fu-Min Liu Xiang-Ru wen Department of Genetics Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Urology the First Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Xuzhou Medical University Clinical Medical College XuzhouJiangsu ProvinceChina Department of Clinical Laboratory Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Research Center for Neurobiology and Department of Neurobiology Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina

Rosmarinic acid,a common ester extracted from Rosemary,Perilla frutescens,and Salvia miltiorrhiza Bunge,has been shown to have protective effects against various *** is an investigation into whether rosmarinic acid can also affect the changes of white matter fibers and cognitive deficits caused by hypoxic *** right common carotid artery of 3-day-old rats was ligated for 2 *** rats were then prewarmed in a plastic container with holes in the lid,which was placed in 37°C water bath for 30 ***,the rats were exposed to an atmosphere with 8% O2 and 92% N2 for 30 minutes to establish the perinatal hypoxia/ischemia injury *** rat models were intraperitoneally injected with rosmarinic acid 20 mg/kg for 5 consecutive *** 22 days after birth,rosmarinic acid was found to improve motor,anxiety,learning and spatial memory impairments induced by hypoxia/ischemia ***,rosmarinic acid promoted the proliferation of oligodendrocyte progenitor cells in the subventricular *** hypoxia/ischemia injury,rosmarinic acid reversed to some extent the downregulation of myelin basic protein and the loss of myelin sheath in the corpus callosum of white matter *** acid partially slowed down the expression of oligodendrocyte marker Olig2 and myelin basic protein and the increase of oligodendrocyte apoptosis marker inhibitors of DNA binding *** data indicate that rosmarinic acid ameliorated the cognitive dysfunction after perinatal hypoxia/ischemia injury by improving remyelination in corpus *** study was approved by the Animal Experimental Ethics Committee of Xuzhou Medical University,China (approval No.20161636721) on September 16,2017.

关键词： cognitive dysfunction corpus callosum differentiation/DNA binding factor 2 hypoxia/ischemia myelin basic protein myelin sheath remyelination rosmarinic acid

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Experimental demonstration of pyramidal neuron-like dynamics dominated by dendritic action potentials based on a VCSEL for all-optical XOR classification task

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Photonics Research 2021年第6期9卷 1055-1061页

作者： YAHUI ZHANG SHUIYING XIANG XINGYU CAO SHIhao Zhao XINGXING GUO AIJUN wen YUE hao State Key Laboratory of Integrated Service Networks Xidian UniversityXi’an 710071China State Key Discipline Laboratory of Wide Bandgap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an 710071China

We experimentally and numerically demonstrate an approach to optically reproduce a pyramidal neuron-like dynamics dominated by dendritic Ca^(2+) action potentials(dCaAPs)based on a vertical-cavity surface-emitting laser(VCSEL)for the first *** biological pyramidal neural dynamics dominated by dCaAPs indicates that the dendritic electrode evoked somatic spikes with current near threshold but failed to evoke(or evoked less)somatic spikes for higher current *** emulating neuron-like dynamics is performed optically based on the injection locking,spiking dynamics,and damped oscillations in the optically injected *** addition,the exclusive OR(XOR)classification task is examined in the VCSEL neuron equipped with the pyramidal neuronlike dynamics dominated by ***,a single spike or multiple periodic spikes are suggested to express the result of the XOR classification task for enhancing the processing rate or *** experimental and numerical results show that the XOR classification task is achieved successfully in the VCSEL neuron enabled to mimic the pyramidal neuron-like dynamics dominated by *** work reveals valuable pyramidal neuron-like dynamics in a VCSEL and offers a novel approach to solve XOR classification task with a fast and simple all-optical spiking neural network,and hence shows great potentials for future photonic spiking neural networks and photonic neuromorphic computing.

关键词： optical dynamics action

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Withaferin A inhibits ferroptosis and protects against intracerebral hemorrhage

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Neural Regeneration Research 2023年第6期18卷 1308-1315页

作者： Zi-Xian Zhou Qi cui Ying-Mei Zhang Jia-Xin Yang wen-Jing Xiang Ning Tian Yan-Lin Jiang Mei-Ling Chen Bin Yang Qing-Hua Li Ru-Jia Liao Laboratory of Neuroscience Affiliated Hospital of Guilin Medical UniversityGuilin Medical UniversityGuilinGuangxi Zhuang Autonomous RegionChina Department of Neurology Affiliated Hospital of Guilin Medical UniversityGuilin Medical UniversityGuilinGuangxi Zhuang Autonomous RegionChina Guangxi Clinical Research Center for Neurological Diseases Affiliated Hospital of Guilin Medical UniversityGuilin Medical UniversityGuilinGuangxi Zhuang Autonomous RegionChina Department of Pharmacology Affiliated Hospital of Guilin Medical UniversityGuilin Medical UniversityGuilinGuangxi Zhuang Autonomous RegionChina

Recent studies have indicated that suppressing oxidative stress and ferroptosis can considerably improve the prognosis of intracerebral hemorrhage(ICH).Withaferin A(WFA),a natural compound,exhibits a positive effect on a number of neurological ***,the effects of WFA on oxidative stress and ferroptosis-mediated signaling pathways to ICH remain *** this study,we investigated the neuroprotective effects and underlying mechanism for WFA in the regulation of ICH-induced oxidative stress and *** established a mouse model of ICH by injection of autologous tail artery blood into the caudate nucleus and an in vitro cell model of hemin-induced *** was injected intracerebroventricularly at 0.1,1 or 5μg/kg once daily for 7 days,starting immediately after ICH *** markedly reduced brain tissue injury and iron deposition and improved neurological function in a dose-dependent manner 7 days after cerebral *** in vitro experiments,cell viability test showed that WFA protected SH-SY5Y neuronal cells against hemin-induced cell ***-linked immunosorbent assays in vitro and in vivo showed that WFA markedly decreased the level of malondialdehyde,an oxidative stress marker,and increased the activities of anti-oxidative stress markers superoxide dismutase and glutathione peroxidase after *** blot assay,quantitative polymerase chain reaction and immunofluorescence results demonstrated that WFA activated the nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)signaling axis,promoted translocation of Nrf2 from the cytoplasm to nucleus,and increased HO-1 *** Nrf2 with siRNA completely reversed HO-1 expression,oxidative stress and protective effects of ***,WFA reduced hemin-induced ***,after treatment with an HO-1 inhibitor,the neuroprotective effects of WFA against hemin-induced ferroptosis were *** test results showed that WFA combined with ferrostatin-1

关键词： behavior brain injuries hemorrhagic stroke ferroptosis heme oxygenase-1 neuroprotection nuclear factor E2-related factor 2 nuclear translocator oxidative stress stroke

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Loss Increase Induced by H_(2) Loading in GeO_(2) Doped Optical Fiber

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Chinese Physics Letters 1997年第3期14卷 187-189页

作者： AN Hong-lin cui Xiao-ming wen Peng-yue LIN Xiang-zhi LIU Hong-du E.Y.B.Pun P.S.Chung Department of Physics National Laboratory of Mesoscopic PhysicsPeking UniversityBeijing 100871 Department of Electronic Engineering City University of Hong Kong

The increase of absorption loss in photosensitivity enhanced optical fiber via H_(2) loading induced in the making process of fiber grating was *** the results it can be seen that hydroxyl induced by exposing the H_(2) loaded GeO_(2)-doped optical fiber to 248nm light causes large absorption loss at 1.4μm.A reaction model is postulated to describe the process that leads to the loss increase and photosensitivity enhancement in GeO_(2)-doped optical fiber.

关键词： fiber optical absorption

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面向撞击载荷的疲劳寿命分析及验证

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机电元件 2024年第1期44卷 39-44页

作者：赵正阳张楚贤冯萃峰蔡立兵刘文成王子文北京航天微机电技术研究所北京100094

针对宇航用波导开关在反复切换撞击工况下的寿命指标要求,开展疲劳寿命设计与验证。在实际工况应力谱难以获得的情况下,基于数值计算方法,采用两种不同方法获取应力谱后开展疲劳寿命分析并进行了试验验证,验证结果表明:基于瞬态动力学... 详细信息

针对宇航用波导开关在反复切换撞击工况下的寿命指标要求,开展疲劳寿命设计与验证。在实际工况应力谱难以获得的情况下,基于数值计算方法,采用两种不同方法获取应力谱后开展疲劳寿命分析并进行了试验验证,验证结果表明:基于瞬态动力学的疲劳分析有较高的准确性,在此基础上,优化改进产品结构,使产品切换寿命满足指标要求。

关键词：波导开关疲劳寿命应力谱瞬态动力学

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