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Effect of herbicide acetochlor on cytochrome P450 monooxygenases and GST of earthworms Eisenia fetida

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Journal of Environmental Sciences 2006年第1期18卷 135-140页

作者： XIAO Neng-wen liU xiang-hui li Wei GE Feng State Key Lab of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

To assess the sublethal toxicity of the herbicide acetochlor to earthworms and to find out biomarkers possible inducted under acetochlor exposure, Eiseniafetida was exposed to artificial soils supplemented with different concentrations of acetochlor（5, 10, 20, 40 and 80 mg/kg soil）. Effects of the acetochlor on cytochrome P450 monooxygenases p-nitroanisole O-demethylase（ODM）, aldrin epoxidase（AE） and glutathione-S-transferases （GSTs） activities were determined. The results revealed cytochrome P450 monooxygenases were elevated with increasing concentrations of acetochlor, and the AE activity increased significantly compared with control at the concentration of 80 mg/kg （P〈0.05）. However, ODM activity from E. fetida was not induced significantly by acetochlor at all treatments（P〉0.05）. Sodium dodecyl sulfate-polyacryamide gel electrophoresis（SDS-PAGE） showed that one protein band was visualized and no evident differences were found in protein profiles between treatments and control. The GST activity increased significantly with longer duration（P〈0.05） and increasing concentrations of acetochlor exposure（P〈0.05）. This study showed that the monooxygenases and GSTs activities in E. fetida could be induced by acetochlor, and thus, the AE and GST could be used in sublethal assays for soil contamination surveys and GST could be used as biomarkers of acetochlor exposure in E. fetida.

关键词： acetochlor Eiseniafetida p-nitroanisole O-demethylase aldrin epoxidase GST

液相色谱-原子荧光光谱法测定地表水中的价态砷

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精细化工中间体 2024年第2期54卷 75-80页

作者：杜江向文礼张玲艳张妍云南省生态环境监测中心云南昆明650034

建立地表水中价态砷(As^(3+)、As^(5+))的液相色谱-原子荧光光谱分析方法,采用Hamilton PRP-X100色谱柱,以磷酸二氢钾和磷酸氢二钠溶液为流动相,流速1.2 mL/min,进样体积100μL,等度洗脱。As^(3+)和As^(5+)的方法检出限分别为0.60、0.69... 详细信息

建立地表水中价态砷(As^(3+)、As^(5+))的液相色谱-原子荧光光谱分析方法,采用Hamilton PRP-X100色谱柱,以磷酸二氢钾和磷酸氢二钠溶液为流动相,流速1.2 mL/min,进样体积100μL,等度洗脱。As^(3+)和As^(5+)的方法检出限分别为0.60、0.69μg/L,相对标准偏差分别为3.6%~11.0%、4.9%~9.0%,加标回收率分别为85.5%~93.6%、84.8%~96.4%,并对某受污染地表水体进行实样测试,验证该方法的可行性。该方法在测定地表水中三价砷和五价砷时,样品前处理简单,只需用0.45μm滤膜过滤;分析速度快,1个样最多只需8 min;仪器灵敏度高,性能稳定;精密度、准确度优;标曲线性良好(r≥0.999);试剂用量少;分离效果好;操作简单,适用于地表水中价态砷(As3+、As5+)的测定。

关键词：液相色谱-原子荧光光谱法地表水三价砷五价砷

Reduced Mythimna separata infestation on Bt corn could benefit aphids

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Insect Science 2021年第4期28卷 1139-1146页

作者： xiang-wen li li-Xiao Du Lei Zhang Yu-Fa Peng Hong-Xia Hua Jörg Romeis Yun-He li College of Plant Science&Technology of Huazhong Agriculture University WuhanHubei ProvinceChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Agroscope Research Division Agroecology and EnvironmentZurichSwitzerland

Use of genetically engineered plants that express insecticidal Cry proteins derived from Bacillus thuringiensis(Bt)have been proven efficacious for managing lepidopteran ***,in some cases herbivores that are not targeted by the Bt trait have increased in *** has been suggested that reduced caterpillar damage to Bt crops could lead to decreased levels of induced plant defensive compounds which might benefit other non-target *** we investigated the potential effect of reduced damage by larvae of Mythimna separata on aphid populations in Bt *** compared the performance of Rhopalosiphum maidis feeding on non-Bt corn plants that had been infested by *** larvae or were *** results showed that caterpillar-infested corn plants significantly reduced the fitness of *** leading to a prolonged nymphal development time,reduced adult longevity and fecundity compared to uninfested ***,the population growth rate of corn aphids feeding on caterpillar-infested corn plants was significantly lower than on uninfested *** expected,the aphids performed significantly better on Lepidoptera-resistant Bt corn than on non-Bt corn when plants were infested with ***,since the caterpillars caused very little damage to the Bt *** current findings indicate that reduced *** infestation could benefit aphid development in Bt *** corn has the potential to be commercialized in China in the near future and aphids and other non-target pests should be monitored in the farming fields.

关键词： genetically engineered crops interspecific relationship Mythimna separata non-target effects Rhopalosiphum maidis

Finite Element Method for Transient Electric Field by Using Indirect Laplace Transform with High Accuracy

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 401-411页

作者： Teng wen xiang Cui Xuebao li Sijia liu Zhibin Zhao State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China China Electric Power Planning&Engineering Institute Beijing 100120China

This paper focuses on the finite element method in the complex frequency domain(CFD-FEM)for the transient electric ***,the initial value and boundary value problem of the transient electric field under the electroquasistatic field in the complex frequency domain is *** addition,the finite element equation and the constrained electric field equation on the boundary are ***,the indirect algorithm of the numerical inverse Laplace transform is *** on it,the calculation procedures of the CFD-FEM are illustrated in ***,the step response,zero-state response under the positive periodic square waveform(PPSW)voltage,and the zero-input response by the CFD-FEM with direct algorithm and indirect algorithm are ***,the reason for the numerical oscillations of the zero-state response under the PPSW voltage is analyzed,and the method to reduce oscillations is *** results show that the numerical accuracy of the indirect algorithm of the CFD-FEM is more than an order of magnitude higher than that of the direct algorithm when calculating the step response of the transient electric *** proposed method can significantly reduce the numerical oscillations of the zero-state response under the PPSW *** proposed method is helpful for the calculation of the transient electric field,especially in the case of frequency-dependent parameters.

关键词： Electroquasistatic field transient electric field finite element method complex frequency domain numerical Laplace transform

pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-Yuan xiang wen-Long Zhang He-Ting li Ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

Seasonal response of nitrogen exchange fluxes to crab disturbance at sediment-water interface in coastal tidal wetlands

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Water Science and Engineering 2024年第2期17卷 129-138页

作者： Guo-fen Hua Shang-qing liu xiang-dong liu Jin-li li Yue Fang wen-ting Xie xiang Xu College of Water Conservancy and Hydroelectric Power Hohai UniversityNanjing 210098China College of Renewable Energy Hohai UniversityNanjing 210098China

Coastal wetlands are hotspots for nitrogen(N)cycling,and crab burrowing is known to transform N in intertidal marsh ***,the underlying mechanisms remain *** study conducted field experiments and used indoor control test devices to investigate the seasonal response of nitrogen to crab disturbance at the sediment-water interface in coastal tidal flat *** results showed that crab disturbance exhibited significant seasonality with large seasonal differences in cave density and *** to crab disturbance,nitrogen fuxes at the sediment-water interface were much greater in the box with crabs than in the box without *** summer,NH-N showed a positive flux from the sediment to the overlying water,but NO2-N and NOg-N showed positive fluxes from the sediment to the overlying water only in early *** winter,NH-N showed a positive flux from the sediment to the overlying water,but NO-N and NO,-N both exhibited positive and negative *** results indicated that the presence of crab burrows can cause the aerobic layer to move downward by approximately 8-15 cm in summer and directly promote nitrification at the sediment surface.

关键词： Coastal tidal flat wetland Crab disturbance Nitrogen flux Nitrification Denitrification Sediment-water interface

Serrated flow behavior of GH536 superalloy under different loading rates at room temperature

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Rare Metals 2024年第5期43卷 2317-2323页

作者： wen-xiang Gao Dong Ma li-li Zhao Fan Ye ling Shao Su-Jun Wu School of Materials Science and Technology Beihang UniversityBeijing100091China

Serrated flow phenomenon has been widely observed among different metals due to the potential influence on their *** tensile tests of nickel-based superalloy GH536 were carried out at loading rates of 0.06,0.60,3.60,and 36.00 mm·min^(-1)at room temperature,*** tensile stress-strain curves demonstrate repetitive and discontinuous yielding behavior,namely serrated *** is observed that the stress-strain curves were dominated by type B serration,and original annealing twin boundaries(TBs)were distorted to various degrees under comparatively different lower tensile *** contrast,the TBs almost disappear,and the type B serrations become smoother and regular under the higher loading *** phenomenon can be attributed to the interactions between TBs and dislocations during tensile *** effects of the mobile and immobile dislocations illustrate the unsteady amplitude of serrations observed in stress-strain *** electron microscope images of tested pieces reveal the interaction of dislocation and TB,with dislocation tangling around the TBs.

关键词： Nickel-based superalloy Serrations Twin boundaries Deformation mechanism

Management of retroperitoneal sarcoma involving the iliac artery:Single-center surgical experience

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World Journal of Clinical Cases 2022年第3期10卷 811-819页

作者： wen-xiang li Han-Xing Tong Chen-Tao Lv Hua Yang Gang Zhao Wei-Qi Lu Yong Zhang Department of General Surgery Shanghai Public Health Clinical CenterFudan UniversityShanghai 200083China Department of General Surgery Zhongshan HospitalFudan UniversityShanghai 200032China

BACKGROUND Management of retroperitoneal sarcoma(RPS)involving the iliac artery is challenging and requires the concerted efforts of multidisciplinary team(MDT)members during surgical *** To summarize the clinicopathologic features of RPS involving the iliac artery and our retroperitoneal soft tissue tumor MDT surgical *** In this retrospective study,15 patients with RPS involving the iliac artery who underwent surgery at our retroperitoneal soft tissue tumor center from July 2004 to June 2020 were *** analyses were performed by Student’s ttest with SPSS *** Complete tumor resection(R0/R1)and iliac artery reconstruction were achieved in all 15 *** the operations were successful,with no serious complications or perioperative *** with bilateral iliac artery reconstruction required a higher intraoperative blood transfusion volume than resection with unilateral iliac artery *** cases were more likely to bleed and required a higher blood transfusion volume than primary *** of January 2021,11 patients were alive,and 4 had *** recurrence occurred in two patients,one of whom developed liver *** Resection of RPS involving iliac vessels is feasible and effective when performed by MDT *** artery oncovascular resection and reconstruction are key to a successful *** blood preparation is important for successful completion of surgery.

关键词： Retroperitoneal sarcoma Vascular reconstruction Multidisciplinary team Iliac artery Blood transfusion

Macrocyclic peptides:up-and-coming weapons to combat antimicrobial resistance

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1786-1787页

作者： wen-Jing Wang xiang-Min Dong Guo-Bo L Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuanChina Key Laboratory of Drug Targeting and Drug Delivery System of Ministry of Education Department of Medicinal ChemistryWest China School of PharmacySichuan UniversityChengduSichuanChina

Recently,two companion papers published in Nature reported a first-in-class tethered macrocyclic peptide antibiotic targeting carbapenem-resistant ***(CRAB)and unveiled their unique antibacterial mechanism,which invol... 详细信息

关键词： outer macrocyclic Macrocyclic