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Risk assessment of heavy metal contaminated soil in the vicinity of a lead/zinc mine

Journal of Environmental Sciences 2005年第6期17卷 881-885页

作者： LI Jing XIE zheng-miao ZHU Yong-guan Ravi Naidu Institute for Soil and Water Resources and Environment Zhejiang University Hangzhou 310029 China Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Centre for Environmental Risk Assessment and Remediation University of South Australia Mawson Lakes SA 5095 Australia

Heavy metal contamination of soils through anthropogenic activities is a widespread and serious problem confronting scientists and regulators throughout the world. In this study we investigated the distribution, chemical species and availability of lead, zinc, cadmium and copper in nine surface（0 to 20 cm） soils from near an abandoned lead/zinc mine tailings located in Shaoxing, Zhejiang, China. Total heavy metal contents ranged from 5271 to 16369 mg/kg for Pb, 387 to 1221 mg/kg for Zn, 3.0 to 9.3 mg/kg for Cd and 65 to 206 mg/kg for Cu. In general, all heavy metals exceeded China National Standards for Soil Environmental Quality of Heavy Metals by a factor of 3-65 times. Comparison of the heavy metal concentrations（Pb, Zn, Cd and Cu） with clay content revealed a strongly significant relationship while significant relationship（ P 〈 0.001 ） was also obtained between Cd ＋ Zn and Pb ＋ Cu. Solid phase speciation of the soils using Tessier procedure showed that the heavy metals were distributed in the order： residual 〉〉 organically complexed-Fe-Mn oxides occluded 〉 carbonate bound 〉 exchangeable 〉 water soluble. In the organic matter fraction, the ratio of Pb（29.1% ） to its total concentration in the soils was higher than those of Zn（4.70% ）, Cd（3.16% ） and Cu（9.50% ）. The percentages of the water soluble and the exchangeable fractions of Pb（1.80% ） and Cd（2.74% ） were markedly greater than those of Zn（0.10% ） and Cu（0.15% ）, suggesting that Pb and Cd are relatively more mobile and hence more toxic in the contaminated soils. Strongly significant relationships between H20-Pb, H20-Zn and H20-Cu, strong positive correlations between H20-Pb, H20-Zn, H20-Cu and organic matter in soil were found. The content of H20-Pb, H20-Zn, H20-Cu was negatively correlated with pH values. The similar negative relationships between pH values and exchangeable heavy metals were also recorded. It is suggested that increasing soil pH or liming the soil could decrease bioavailability of heavy met

关键词： fractionation heavy metal mining tailings risk assessment soil pollution

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ZnS/Bacterial Cellulose/Epoxy Resin(ZnS/BC/E56) Nanocomposites with Good Transparency and Flexibility

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Journal of Materials Science & Technology 2016年第2期32卷 153-157页

作者： Fangyi guan Shiyan Chen Jingjing Yao Weili zheng Huaping Wang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Key Laboratory of High-performance Fibers and Products Ministry of Education College of Materials Science and Engineering Donghua University

ZnS/bacterial cellulose/epoxy resin （ZnS/BC/E56） nanocomposites with good transparency and flexibil-ity were prepared and characterized. When the precursor Zn^2＋ concentrations were not more than I wt%, the size of the introduced ZnS nanoparticles was smaller than 50 nm and the distribution was homo-geneous within the composites. Under the condition, outstanding transmittance more than 70g in the visible light was obtained. By incorporation of ZnS nanoparticles with excellent thermo-optic stability to the composites, the thermo-optic coefficient was obviously increased from -361 × 10^-6 to -310 × 10^-6K^-1. The good flexibility, optical and mechanical properties endow the nanocomposites potential applica- tions in the flexible optoelectronic materials.

关键词： ZnS Bacterial cellulose Epoxy resin Nanocomposites Properties

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Consensus Clustering for Bi-objective Power Network Partition

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 973-982页

作者： yi Wang Luzian Lebovitz Kedi zheng Yao Zhou the Power Systems Laboratory ETH Zurich8092 ZurichSwitzerland Department of Elctrical Engineering Tsinghua UniversityBeijing 100084China School of Engineering the University of EdinburghEH93FBEdinburghUK

Partitioning a complex power network into a number of sub-zones can help realize a divide-and-conquer’management structure for the whole system,such as voltage and reactive power control,coherency identification,power system restoration,*** partitioning methods have been proposed by defining various distances,applying different clustering methods,or formulating varying optimization models for one specific ***,a power network partition may serve two or more objectives,where a trade-off among these objectives is *** paper proposes a novel weighted consensus clustering-based approach for bi-objective power network *** varying the weights of different partitions for different objectives,Pareto improvement can be explored based on the node-based and subset-based consensus clustering *** studies on the IEEE 300-bus test system are conducted to verify the effectiveness and superiority of our proposed method.

关键词： Consensus clustering network partition bi-objective partition machine learning

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Payne Effect and Weak Overshoot in Rubber Nanocomposites

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Chinese Journal of Polymer Science 2022年第1期40卷 85-92页

作者： Zhi-Yun Li yi-Hu Song Qiang zheng MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Payne effect and its associated weak overshoot are of importance for understanding and regulating the softening of rubber nanocomposites under large amplitude ***,Payne effect in diverse filled vulcanizates is investigated for generalizing the common *** curves of strain amplitude dependent storage modulus are created with respect to microscopic strain amplitude of the matrix,revealing a matrix-dominated elastic nonlinearity being independent of type and dispersity of filler,crosslinking density and sol fraction of matrix and filler-rubber interfacial ***,carbonaceous fillers with higher affinity to the rubber matrices yield lower strain amplification and higher overshoot behavior in comparison with siliceous *** investigation would be illuminating for preparing rubber nanocomposites with optimized reinforcement and softening performances.

关键词： Vulcanizate nanocomposites Payne effect Weak overshoot

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Reversal of circularly polarized luminescence direction and an“onoff”switch driven by exchange between UV light irradiation and the applied direct current electric field

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Science China Chemistry 2022年第10期65卷 1945-1952页

作者： Kun Yao zheng Liu Hang Li Dan Xu Wen-Hua zheng yi-Wu Quan yi-Xiang Cheng Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of High Performance Polymer Material and Technology of Ministry of Education Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

We report the rational design of a dual stimulus-activated quaternary chiral emission nematic liquid crystals(Q-N*-LCs)containing light-driven chiral dopant R-S-R-1,a static chiral dopant S-2 and an achiral Nile Red(NR)in a nematic liquid crystal(SLC1717).The dopant R-S-R-1 acts as a dynamic chiral donor and an energy donor,and the achiral NR serves as a circularly polarized luminescence(CPL)emitter and energy ***,this kind of Q-N*-LCs appears reversal CPL emission direction(L-CPL)using 365 nm UV light irradiation compared with the initial state(R-CPL).Most importantly,the“On-Off”CPL switch behavior of Q-N*-LCs can be repeatedly driven by revoking or rearranging the applied direct current(DC)electric *** OR chiral information logic gate demonstrates that this dual driven Q-N*-LCs can be potentially used for chiral information storage and coding.

关键词： chiral supramolecular liquid crystals circularly polarized luminescence light and electricity dual stimuli-activated Förster resonance energy transfer

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HUMAN MITOCHONDRIAL tRNA MUTATIONS IN MATERNALLY INHERITED DEAFNESS

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Journal of Otology 2013年第1期8卷 44-50页

作者： zheng Jing GONG Sha-sha TANG Xiao-wen ZHU yi guan Min-xin Department of Genetics College of Life SciencesZhejiang University Attardi Institute of Mitochondrial Biomedicine Wenzhou Medical University

Mutations in mitochondrial tRNA genes have been shown to be associated with maternally inherited syn-dromic and non-syndromic deafness. Among those, mutations such as tRNALeu(UUR) 3243A>G associated with syndromic deafness are often present in heteroplasmy, and the non-syndromic deafness-associated tRNA mu-tations including tRNASer(UCN) 7445A>G are often in homoplasmy or in high levels of heteroplasmy. These tRNA mutations are the primary factors underlying the development of hearing loss. However, other tRNA mutations such as tRNAThr 15927G>A and tRNASer(UCN) 7444G>A are insufficient to produce a deafness phe-notype, but always act in synergy with the primary mitochondrial DNA mutations, and can modulate their phenotypic manifestation. These tRNA mutations may alter the structure and function of the corresponding mitochondrial tRNAs and cause failures in tRNAs metabolism. Thereby, the impairment of mitochondrial protein synthesis and subsequent defects in respiration caused by these tRNA mutations, results in mitochon-drial dysfunctions and eventually leads to the development of hearing loss. Here, we summarized the deaf-ness-associated mitochondrial tRNA mutations and discussed the pathophysiology of these mitochondrial tRNA mutations, and we hope these data will provide a foundation for the early diagnosis, management, and treatment of maternally inherited deafness.

关键词： deafness mitochondria tRNA primary mutation secondary mutation maternally inherited

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Multifunctional MgF_2/Polydopamine Coating on Mg Alloy for Vascular Stent Application

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Journal of Materials Science & Technology 2015年第7期31卷 733-743页

作者： Xiaoli Liu Zhen Zhen Jing Liu Tingfei Xi Yudong zheng Shaokang guan Yufeng zheng Yan Cheng School of Materials Science and Technology University of Science and Technology Beijing Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University Shenzhen Research Institute Peking University Materials Research Center School of Materials Science and EngineeringZhengzhou University

Mg alloy is of great potential in the application of vascular stent due to its degradation in physical environment and proper mechanical property. However its mechanical integrity does not meet the clinical requirement clue to relatively fast degradation. Besides, in order to accelerate the re- endothelialization of Mg-based stents, it needs surface modification to improve the attachment, growth and adhesion of endothelial cells （ECs）. To solve the main obstacles, an anti-corrosion and quick endothelialization coating was prepared on novel Mg-Zn-Y-Ncl alloy via a simple two-step immersion method in the present study, first in hydrofluoric acid （HF） then in dopamine tris-Hydrochloric acid （tris -HCI） solution. The coating was uniform and thin, which consisted of two layers--the upper was pol- yclopamine （PDA） layer and the lower was MgF2 layer. The alloy with the coating demonstrated dramatic corrosion resistance enhancement in vitro by immersion test and electrochemical test. Moreover the HF- PDA-treated Mg alloy exhibited great performance of cell adhesion and proliferation. The coating created a favorable environment for ECs to have a competitive advantage over vascular smooth muscle ceils （VSMCs）, which was preferable for re-enclothelialization. The results suggest that HF-PDA-treatecl Mg -Zn-Y-Nd alloy has great potential in the application of vascular stent and the surface coating method is of great aPPlication value in biodegraclable Mg alloy stent clue to its simplicity and effectiveness.

关键词： Mg-Zn-Y-Nd alloyVascular stentHF converted layerPolydopamineCorrosion resistanceRe-endotheliazation

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Endothelial METRNL determines circulating METRNL level and maintains endothelial function against atherosclerosis

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Acta Pharmaceutica Sinica B 2023年第4期13卷 1568-1587页

作者： Sili zheng Zhiyong Li Jie Song Pin Wang Jian Xu Wenjun Hu yi Shi Qi Qi Zhuwei Miao Yunfeng guan Chaoyu Miao Department of Pharmacology Second Military Medical University/Naval Medical UniversityShanghai 200433China Changhai Hospital Second Military Medical University/Naval Medical UniversityShanghai 200433China Zhongshan Hospital Fudan UniversityShanghai 200032China

METRNL is a recently identified secreted protein with emerging *** study is to find major cellular source of circulating METRNL and to determine METRNL novel ***,we show METRNL is abundant in human and mouse vascular endothelium and released by endothelial cells using endoplasmic reticulum-Golgi apparatus *** creating endothelial cell-specific Metrnl knockout mice,combined with bone marrow transplantation to produce bone marrow-specific deletion of Metrnl,we demonstrate that most of circulating METRNL(approximately 75%)originates from the endothelial *** endothelial and circulating METRNL decrease in atherosclerosis mice and *** generating endothelial cell-specific Metrnl knockout in apolipoprotein E-deficient mice,combined with bone marrow-specific deletion of Metrnl in apolipoprotein E-deficient mice,we further demonstrate that endothelial METRNL deficiency accelerates ***,endothelial METRNL deficiency causes vascular endothelial dysfunction including vasodilation impairment via reducing eNOS phosphorylation at Ser1177 and inflammation activation via enhancing NFκB pathway,which promotes the susceptibility of *** METRNL rescues METRNL deficiency induced endothelial *** findings reveal that METRNL is a new endothelial substance not only determining the circulating METRNL level but also regulating endothelial function for vascular health and *** is a therapeutic target against endothelial dysfunction and atherosclerosis.

关键词： METRNL Secreted protein Endothelium Endothelial function Bone marrow Atherosclerosis

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Poly(GMA/MA/MBAA)Copolymer Beads:a Highly Efficient Support Immobilizing Penicillin G Acylase

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Chinese Chemical Letters 2006年第1期17卷 129-132页

作者： Ping XUE guan Zhong LU Wan yi LIU Key Laboratory of Energy Source and Chemical Engineering Ningxia University Yinchuan 750021 Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237

The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate （GMA）/methacrylamide（MA）/N,N＇-methylene-bis（acrylamide）（MBAA）was synthesized using the industrial agents by inverse suspension polymerization. The apparent activity of the immobilized penicillin G acylase reached 1096 IU/g for hydrolysis penicillin G on the beads with diameter of 0.11-0.13 ram, and it changed hardly after 50 cycles. It can be expected to be a good potential in industrial application,

关键词： Poly(GMA/MA/MBAA) copolymer beads penicillin G acylase immobilization,inverse suspension polymerization.

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Transcription factor glucocorticoid modulatory element-binding protein 1 promotes hepatocellular carcinoma progression by activating Yes-associate protein 1

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World Journal of Gastrointestinal Oncology 2023年第6期15卷 988-1004页

作者： Cheng Chen Hai-guan Lin zheng Yao yi-Ling Jiang Hong-Jin Yu Jing Fang Wei-Na Li Department of Medical Oncology Zhejiang Xiaoshan HospitalHangzhou 311202Zhejiang ProvinceChina Department of General Surgery People’s Liberation Army Strategic Support Force Characteristic Medical CenterBeijing 100101China Department of Radiation Oncology Cancer Hospital of The University of Chinese Academy of SciencesHangzhou 310022Zhejiang ProvinceChina

BACKGROUND Glucocorticoid modulatory element-binding protein 1(GMEB1),which has been identified as a transcription factor,is a protein widely expressed in various ***,the dysregulation of GMEB1 is linked to the genesis and development of multiple *** To explore GMEB1’s biological functions in hepatocellular carcinoma(HCC)and figuring out the molecular *** GMEB1 expression in HCC tissues was analyzed employing the StarBase *** staining,Western blotting and quantitative realtime PCR were conducted to examine GMEB1 and Yes-associate protein 1(YAP1)expression in HCC cells and *** counting kit-8 assay,Transwell assay and flow cytometry were utilized to examine HCC cell proliferation,migration,invasion and apoptosis,*** JASPAR database was employed for predicting the binding site of GMEB1 with YAP1 ***-luciferase reporter gene assay and chromatin immunoprecipitation-qPCR were conducted to verify the binding relationship of GMEB1 with YAP1 promoter *** GMEB1 was up-regulated in HCC cells and tissues,and GMEB1 expression was correlated to the tumor size and TNM stage of HCC ***1 overexpression facilitated HCC cell multiplication,migration,and invasion,and suppressed the apoptosis,whereas GMEB1 knockdown had the opposite ***1 bound to YAP1 promoter region and positively regulated YAP1 expression in HCC *** GMEB1 facilitates HCC malignant proliferation and metastasis by promoting the transcription of the YAP1 promoter region.

关键词： Hepatocellular carcinoma Glucocorticoid modulatory element-binding protein 1 Yes-associate protein 1 Apoptosis Proliferation

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