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Mechanisms of photochemical release of dissolved organic matter and iron from resuspended sediments

Journal of Environmental Sciences 2021年第6期33卷 288-295页

作者： Bin hu Peifang wang Tianli Bao jin Qian Xun wang Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education Hohai UniversityNanjing 210098China College of Environment Hohai UniversityNanjing 201198China

Photochemical reactions can alter the transformation of sedimentary organic matter into dissolved organic matter(DOM)and affect its ultimate fate in water *** the present study,the photorelease of DOM and Fe from resuspended lake sediments was investigated under different O_(2)and NO_(3)-concentration conditions to study the mechanisms of DOM and Fe *** amount of photoreleased Fe,which ranged from 0.22 to 0.70μmol/L,was significantly linearly correlated with the amount of photoreleased DOM.O_(2)and NO_(3)-could promote the photochemical release of DOM and Fe,especially during the initial 4 h *** general,the order of the photorelease rates of DOM and Fe under different conditions was as follows:NO_(3)-/aerobic>aerobic≈NO_(3)-/anaerobic>*** photorelease rates of DOM and Fe were higher for the initial 4 hr irradiation than these for the subsequent 8 hr *** photorelease of DOM and Fe is thought to proceed via direct photodissolution and indirect *** relative contributions of indirect processes(>60%)was much greater than that of direct photodissolution(<40%).The photoproduced H 2 O_(2)under aerobic and anaerobic conditions indicated that hydroxyl radicals(·OH)are involved in the photorelease of ***·OH scavengers,it was found that 38.7%,53.7%,and 77.6%of photoreleased DOM was attributed to·OH under anaerobic,aerobic,and NO_(3)-/aerobic conditions,*** findings provide insights for understanding the mechanisms and the important role of·OH in the DOM and Fe photorelease from resuspended sediments.

关键词： Dissolved organic matter Fe Photorelease Hydroxyl radical Resuspended sediments

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Rational cubic/quartic Said-Ball conics

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Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 198-212页

作者： hu Qian-qian wang Guo-jin Department of Mathematics Zhejiang University Hangzhou 310027 College of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018.

In CAGD, the Said-Ball representation for a polynomial curve has two advantagesover the B′ezier representation, since the degrees of Said-Ball basis are distributed in a step *** advantage is that the recursive algorithm of Said-Ball curve for evaluating a polynomialcurve runs twice as fast as the de Casteljau algorithm of B′ezier curve. Another is that theoperations of degree elevation and reduction for a polynomial curve in Said-Ball form are simplerand faster than in B′ezier form. However, Said-Ball curve can not exactly represent conics whichare usually used in aircraft and machine element design. To further extend the utilizationof Said-Ball curve, this paper deduces the representation theory of rational cubic and quarticSaid-Ball conics, according to the necessary and su？cient conditions for conic representation inrational low degree B′ezier form and the transformation formula from Bernstein basis to Said-Ballbasis. The results include the judging method for whether a rational quartic Said-Ball curve is aconic section and design method for presenting a given conic section in rational quartic Said-Ballform. Many experimental curves are given for confirming that our approaches are correct ande？ective.

关键词： Rational Said-Ball curve Rational B′ezier curve conics.

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Representing conics by low degree rational DP curves

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 278-289页

作者： Qian-qian hu Guo-jin wang Department of Mathematics Zhejiang University Hangzhou 310027 China College of Statistics and Mathematics Zhejiang Gongshang University Hangzhou 310018 China

A DP curve is a new kind of parametric curve defined by Delgado and Pena （2003）; Jt has very good properties when used in both geometry and algebra, i.e., it is shape preserving and has a linear time complexity for evaluation. It overcomes the disadvantage of some generalized Ball curves that are fast for evaluation but cannot preserve shape, and the disadvantage of the B6zier curve that is shape preserving but slow for evaluation. It also has potential applications in computer-aided design and manufacturing （CAD/CAM） systems. As conic section is often used in shape design, this paper deduces the necessary and suffi- cient conditions for rational cubic or quartic DP representation of conics to expand the application area of DP curves. The main idea is based on the transformation relationship between low degree DP basis and Bemstein basis, and the representation tbeory of conics in rational low degree B6zier form. The results can identify whether a rational low degree DP curve is a conic section and also express a given conic section in rational low degree DP form, i.e., give positions of the control points and values of the weights of rational cubic or quartic DP conics. Finally, several numerical examples are presented to validate the effectiveness of the method.

关键词： Conic sections Bernstein basis DP basis Rational low degree Bezier curves Rational low degree DP curves

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Alzheimer's disease and gut microbiota

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Science China(Life Sciences) 2016年第10期59卷 1006-1023页

作者： Xu hu Tao wang Feng jin Key Laboratory of Mental Health Institute of Psychology Chinese Academy of Sciences

Alzheimer＇s disease （AD） is a most common neurodegenerative disorder, which associates with impaired cognition. Gut microbiota can modulate host brain function and behavior via microbiota-gut-brain axis, including cognitive behavior. Germ-free animals, antibiotics, probiotics intervention and diet can induce alterations of gut microbiota and gut physiology and also host cognitive behavior, increasing or decreasing risks of AD. The increased permeability of intestine and blood-brain barrier induced by gut rnicrobiota disturbance will increase the incidence of neurodegeneration disorders. Gut microbial metabolites and their effects on host neurochemical changes may increase or decrease the risk of AD. Pathogenic microbes infection will also increase the risk of AD, and meanwhile, the onset of AD support the ＂hygiene hypothesis＂. All the results suggest that AD may begin in the gut, and is closely related to the imbalance of gut microbiota. Modulation of gut microbiota through personalized diet or beneficial microbiota intervention will probably become a new treatment for AD.

关键词： Alzheimer's disease gut microbiota leaky gut leaky brain diet infection hygiene hypothesis

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Nano Beta tricalcium phosphate/gelatin/velvet antler polypeptide materials stimulates the proliferation of bone marrow mesenchymal stem cells and their differentiation into osteoblasts

Nano Beta tricalcium phosphate/gelatin/velvet antler polypep...

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中国畜牧兽医学会兽医药理毒理学分会第十次研讨会

作者： Song Yu~a,Zhang Zheng-Yao~b,Liu Xiao-Feng~b,hu jin-ping~a,wang Xiao-liang~a,Zhao Guang-hou~a,Deng Xu-ming~a a College of Animal Science and Veterinary Medicine,Jilin University,Chang chun,130062 b College of Pharmacy,Jilin University,Chang chun,130012

＜正＞【Object】To explore the proliferation and differential effect of the nano beta tricalcium phosphate/ gelatin /velvet antler polypeptide（VAP）materials on mesenchymal stem cells（MSCs） of New Zealand rabbits.【Methods】MTT assay was used to determine the proliferation effect of the materials on *** phosphatase activity and mineralization nodules was examined to evaluated the differentiation effect of materials on MSCs.【Results】There was a significant increase in alkaline phosphatase activity and mineralization nodus compared with the materials with no VAP.【Concluldsions】These results indicated a beneficial influence of Nano tricalcium phosphate/ gelatin /velvet antler polypeptide materials on bone defects therapy.

关键词： Nano tricalcium phosphate gelatin velvet antler polypeptide materials mesenchymal stem cells Proliferation Differentiation

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MODIFIED MORLEY ELEMENT METHOD FOR A FOURTH ORDER ELLIPTIC SINGULAR PERTURBATION PROBLEM

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Journal of Computational Mathematics 2006年第2期24卷 113-120页

作者： Ming wang jin-chao Xu Yu-cheng hu LMAM School of Mathematical Science Peking University Beijing 100871 China School of Mathematical Science Peking University Beijing 100871 China and Department of Mathematics Pennsylvania State University USA School of Mathematical Science Peking University Beijing 100871 China

This paper proposes a modified Morley element method for a fourth order elliptic singular perturbation problem. The method also uses Morley element or rectangle Morley element, but linear or bilinear approximation of finite element functions is used in the lower part of the bilinear form. It is shown that the modified method converges uniformly in the perturbation parameter.

关键词： Morley element Singular perturbation problem.

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RNA interference affects tumorigenicity and expression of insulin-like growth factor-1,insulin-like growth factor-1 receptor,and basic fibroblast growth factor-2 in rat C6 glioma cells

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Neural Regeneration Research 2009年第8期4卷 597-605页

作者： Wanli Dong jin hu Shaoyan hu Yuanyuan wang Juean Jiang Youxin jin Department of Neurology First Affiliated Hospital of Soochow University Suzhou 215006 Jiangsu Province China Sixth People's Hospital of Shanghai Jiao Tong University Shanghai 200233 China State Key Laboratory of Molecular Biology Institute of Biochemistry Chinese Academy of Sciences Shanghai 200031 China

BACKGROUND： human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μ

关键词： small interference RNA basic fibroblast growth factor-2 insulin-like growth factor 1 insulin-like growth factor 1 receptor C6 glioma cell line

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Unraveling the Heterogeneity of Epoxy-amine Networks by Introducing Dynamic Covalent Bonds

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Chinese Journal of Polymer Science 2023年第6期41卷 926-932,I0009页

作者： hu Xu Yao Zhang Hao wang jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Epoxy resins are a kind of universal thermosetting plastics,which are widely used as structural materials in various ***,it is necessary to understand the network structure of epoxy ***,it is challenging to reveal the network heterogeneity of epoxy resins due to the permanent covalent ***,we provide a novel strategy to characterize the network heterogeneity of epoxy resins by using the dynamic covalent bonds to replace the conventional covalent *** dynamic covalent bonds can reorganize under heat stimulus and the network keeps a constant crosslinking density during topological rearrangement,making it convenience to study the heterogeneity of epoxy ***-Williams-Watts(KWW)stretched exponential function is used to fit the stress relaxation data,and the parametersβandσperm/σ0 extracted from KWW equation indicate the network becomes more homogenous with the stoichiometric ratio of epoxy groups and amines decreases from 1/1 to 1/*** method proves that the side reaction between epoxy and hydroxyl is the main origin of the structural heterogeneity in epoxy resins compared to the secondary amines network.

关键词： resins bonds amines

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长沙市孕早期非吸烟孕妇被动吸烟KAP调查

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实用预防医学 2011年第10期18卷 1877-1878页

作者：周婧瑜胡劲松王进朱江湖南省长沙市疾病预防控制中心湖南长沙410001

目的了解长沙市非吸烟孕妇被动吸烟情况以及相关知识、态度和行为,为减少孕妇被动吸烟提供科学依据。方法对641位孕龄不大于12周的非吸烟孕早期孕妇进行有关被动吸烟的问卷调查,SPSS13.0统计软件进行分析。结果孕妇对被动吸烟具体可以... 详细信息

目的了解长沙市非吸烟孕妇被动吸烟情况以及相关知识、态度和行为,为减少孕妇被动吸烟提供科学依据。方法对641位孕龄不大于12周的非吸烟孕早期孕妇进行有关被动吸烟的问卷调查,SPSS13.0统计软件进行分析。结果孕妇对被动吸烟具体可以导致的危害了解不足;对在餐厅、咖啡吧等餐饮娱乐场所吸烟的容忍度显著高于医院、中小学校、公交车等公共场所;对周围吸烟者进行劝阻时,对丈夫的预计成功率最高,其次为父母、公公婆婆等亲密家庭成员,对单位领导和公共场所吸烟的陌生人的预计成功率最低,均不足35%。结论减少孕妇被动吸烟刻不容缓,孕妇需要掌握更多被动吸烟危害的知识以及劝阻他人当面吸烟的技巧,以加强自我保护。

关键词：被动吸烟孕妇调查

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Trans-scale study on the thermal response and initiation of ternary fluoropolymer-matrix reactive materials under shock loading

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Defence Technology（防务技术） 2023年第3期21卷 184-195页

作者： Chao Ge Die hu jin wang Qingbo Yu Haifu wang Yuanfeng Zheng School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China

To investigate the thermal response and initiation behavior of ternary fluoropolymer-matrix PTFE/Al/W reactive materials,a research combining shock loading tests and trans-scale modelling is *** the basis of a good agreement of the numerically simulated and tested shock wave propagation,the significant impact of component ratios and particle sizes on the evolution of mesoscopic temperature,hot-spots and initiation is well characterized and *** demonstrate that as the content of W increases,the range of mesoscopic high-temperature area increases and tends to distribute more uniform,while material with smaller W particles causes more intense particle deformation and larger temperature *** time to reach the critical temperature shows positive correlation to the content of W,while the critical temperature of hot-spots shows negative correlation to the particle size of *** PTFE/Al/W of high density,with the increase of W particle size,the reaction rate decrease,however the time to reach the peak reaction rate shortens.

关键词： deformation shock loading

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