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Understanding the endocrine disruption of chiral pesticides:The enantioselectivity in estrogenic activity of synthetic pyrethroids

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Science China Chemistry 2010年第5期53卷 1003-1009页

作者： WANG Cui 1,ZHANG Quan 1,ZHANG XiaoFeng 1,LIU Jing 2 & LIU WeiPing 2 1College of Biological and Environmental Engineering,zhejiang university of Technology,Hangzhou 310032,China 2Key Laboratory of Environmental Remediation and Ecosystem Health,Ministry of Education College of Environmental and Resource sciences,zhejiang university,Hangzhou 310029,China 1. College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China2. Key Laboratory of Environmental Remediation and Ecosystem Health Ministry of Education College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) *** results showed that the estrogenic potential of cis-BF was mainly attributed to *** PM nor Fen showed estrogenic ***,two stereoisomers of PM possessed estrogenic potential activities.αR-2R-Fen and αS-2S-Fen also induced the β-galactosidase *** inability to initiate the reporter gene expression by the racemic chemicals may be due to the low ratios of these isomers or the antagonism among *** strong hydrophobic interaction and the hydrogen bond between positive estrogenic isomers and ERα support our biological testing *** research demonstrated that the enantioselective estrogenic activity of chiral SPs was due to selective binding between their isomers and the ERα*** data suggests that enantioselectivity of these chiral pesticides is significant to their estrogenic activities.

关键词： enantioselectivity synthetic pyrethroids (SPs) endocrine disruption yeast molecular docking

The Role of Propeptide in the Refolding of Human Group IB Phospholipase A2

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 583-588页

作者： Hong-Qiang CHENG1 and Gen-Jun XU1,2*Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Shanghai 200031, China 2College of Life Science, zhejiang university of sciences, Hangzhou 310033, China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences College of Life Science Zhejiang University of Sciences

Human group IB phospholipase A2 (IB-PLA2) and its zymogen (proIB-PLA2) were purified from E. coli. Refolding was carried out by diluting the denatured forms of both IB-PLA2 and proIB-PLA2 with renaturation buffer in which the disulfide bonds were completely reduced. The refolding yield of proIB-PLA2 was increased by about 50% over that of the mature enzyme. The refolding of IB-PLA2 usually produced aggregates under normal conditions, as determined by light scattering. In addition, the unfolding experiments showed that the mature enzyme was more stable than the proenzyme toward denaturants in the presence of DTT. Results suggested that the N-terminal sequence rather than its conformation of human proIB-PLA2 played an important role in the refolding process.

关键词： human group IB phospholipase A2 (IB-PLA2) refolding first disulfide bond propeptide

Isotope Tracing and Prospecting Assessment of Gold-Silver Deposits in zhejiang Province

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Acta Geologica Sinica(English Edition) 1997年第3期71卷 293-304页

作者： Chen Haoshou and Xu Butai Department of Earth sciences, zhejiang university, Hangzhou, zhejiang zhejiang Institute of Geology and Mineral Resources, Hangzhou, zhejiang Liu Xinzhu

Three different types of gold and silver deposits in zhejiang Province(Huangshan gold deposit, Zhilingtou gold-silver deposit and Haoshi silver deposit) showmarked differences in lead and strontium isotopic composition, suggesting three differentsources and geneses of these deposits. The Huangshan gold deposit features low initial Srisotope ratios and low μ values or low content of radiogenic Pb and its ore-forming materialscame primarily from the upper mantle; the Zhilingtou gold-silver deposit shows high initial Srisotope ratios and high μ values or high content of radiogenic Pb and the ore-forming materialswere derived mainly from the upper crust; and the Haoshi silver deposit has its Pb and Srisotope ratios between the above two cases with the ore-forming materials stemming from boththe mantle and the crust. The characteristic Pb isotopic composition may serve as an indicatorfor prospecting for different types of ore deposits.

关键词： isotope tracing gold deposit silver deposit zhejiang Province

Energy functionals and killing transform

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Chinese Science Bulletin 1997年第19期42卷 1593-1596页

作者： YING JiangangDepartment of Mathematics, zhejiang university, Hangzhou 310027, China Istitute of Applied Mathematics, Chinese Academy of sciences, Beijing 100080, China Department of Mathematics Zhejiang University Hangzhou China Istitute of Applied Mathematics Chinese Academy of Sciences Beijing China

LET X=（Xt,Px） be a right Markov process with state space （E,ε）, semigroup （P1） andresolvent （Uq）. As in ref.[1, 2], we denote by Excq（X ）, Disq（X） and Conq（X） thecones of excessive, dissipative, conservative measures of X, respectively, and by Sq（X） thecone of excessive functions of X. By convention we drop the superscript q when it is zero. LetMF be the set of all exact multiplicative functional of X. For any given M∈MF, writeEM:= {x∈E:PM0 = 1 = 1} and SM: = inf} t>0: M1= 0 } for the set of

关键词： right processes multiplicative functionals Revuz measures energy functional capacity.

Boundedness of a class of super singular integral operators and the associated commutators

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Science China Mathematics 2004年第6期47卷 842-853页

作者： CHEN Qionglei & ZHANG Zhifei Department of Mathematics, zhejiang university, Hangzhou 310028, China Academy of Mathematics and System sciences, Chinese Academy of sciences, Beijing 100080, China 1. Department of Mathematics Zhejiang University 310028 Hangzhou China 2. Academy of Mathematics and System sciences Chinese Academy of Sciences 100080 Beijing China

In this paper we give the (L p α, L p ) boundedness of the maximal operator of a class of super singular integrals defined by $$T_{\Omega ,\alpha }^* f(x) = \mathop {\sup }\limits_{\varepsilon > 0} \left| {\int_{|x - y| > \varepsilon } {b(|y|)} \Omega (y)|y|^{ - n - \alpha } f(x - y)dy} \right|,$$ which improves and extends the known result. Moreover, by applying an off-Diagonal T1 Theorem, we also obtain the (L p , L q ) boundedness of the commutator defined by $$C_{\Omega ,\alpha } f(x) = p.v. \int_{\mathbb{R}^n } {(A(x)} - A(y))\Omega (x - y)|x - y|^{ - n - \alpha } f(y)dy.$$

关键词： singular integral operator maximal operator commutator T1 Theorem

Ring-like nucleoid does not play a key role in radioresistance of Deinococcus radiodurans

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Science China(Life sciences) 2007年第4期50卷 525-529页

作者： GAO GuanJun, LU HuiMing, YIN LongFei & HUA YueJin Institute of Nuclear-Agricultural sciences, zhejiang university, Hangzhou 310029, China 1. Institute of Nuclear-Agricultural sciences Zhejiang University Hangzhou 310029 China

The conclusion based on transmission electron microscopy, "the tightly packed ring-like nucleoid of the Deinococcus radiodurans R1 is a key to radioresistance", has instigated lots of debates. In this study, according to the previous research of PprI’s crucial role in radioresistance of D. radiodurans, we have attempted to examine and compare the nucleoid morphology differences among wild-type D. ra-diodurans R1 strain, pprI function-deficient mutant (YR1), and pprI function-complementary strains (YR1001, YR1002, and YR1004) before and after exposure to ionizing irradiation. Fluorescence mi-croscopy images indicate: (1) the majority of nucleoid structures in radioresistant strain R1 cells ex-hibit the tightly packed ring-like morphology, while the pprI function-deficient mutant YR1 cells carrying predominate ring-like structure represent high sensitivity to irradiation; (2) as an extreme radioresistant strain similar to wild-type R1, pprI completely function-complementary strain YR1001 almost displays the loose and irregular nucleoid morphologies. On the other hand, another radioresistant pprI partly function-complementary strain YR1002’s nucleiods exhibit about 60% ring-like structure; (3) a PprI C-terminal deletion strain YR1004 consisting of approximately 60% of ring-like nucleoid is very sensi-tive to radiation. Therefore, our present experiments do not support the conclusion that the ring-like nucleoid of D. radiodurans does play a key role in radioresistance.

关键词： Deinococcus radiodurans R1 ring-like nucleoid pprI ionizing irradiation radioresistance

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of sciences, Beijing 100049, China 2. Graduate School of Chinese Academy of sciences, Beijing 100049, China 3. Department of Physics, Zhoukou Normal university, Zhoukou 466100, China 4. Research Imaging center, university of Texas Health Science center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering center, Institute of Automation, Chinese Academy of sciences, Beijing 100049, China 6. Department of Physics, zhejiang university, Hangzhou 310027, China) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of sciences Beijing China [c]Department of Physics Zhoukou Normal University Zhoukou China [d]Research Imaging center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of Physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

Potential land for plantation of Jatropha curcas as feedstocks for biodiesel in China

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Science China Earth sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1,2,3,HUANG JiKun 1,3 & DENG XiangZheng 1,3 1 Institute of Geographic sciences and Natural Resources Research,Chinese Academy of sciences,Beijing 100101,China 2 Department of Economics and Management,zhejiang Forestry university,Linan 311300,China 3 center for Chinese Agricultural Policy,Chinese Academy of sciences,Beijing 100101,China 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in China and the rest of *** with the national food security,China recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in China's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest China

Geochemical migration of arsenic and its environmental efect

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Journal of Environmental sciences 1997年第2期9卷 37-46页

作者： Weng Huanxin, Lan Xiang Department of Earth sciences, zhejiang university, Hangzhou 310027, China

This paper presents the results of a field study regarding the transport and environmental fate of arsenic. Concentrations of arsenic and various forms of its compounds in rock, soil, river water, and river bottom deposits in an area near Hangzhou, China, were measured and analyzed. On the basis of these field data, the source and interface transfer of arsenic were discussed. A few very interesting findings were reported. This paper indicates that there was relatively low arsenic concentration in Jing Hang Canal, whereas, rather high arsenic concentration in the river bottom mud was found. The paper attributed this phenomenon to mechanism of arsenic deposition and absorption in the water column, the canal has a rather high self purification ability relative to the arsenic input.

关键词： arsenic geochemical migration environmental effect.