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Response of Superoxide Dismutase,Catalase,and ATPase Activity in Bacteria Exposed to Acetamiprid

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Biomedical and Environmental Sciences 2006年第4期19卷 309-314页

作者： XIAO-HUA YAO HANG MIN ZHEN-mei lv College of Life Sciences Zhejiang University Hangzhou 310058 Zhejiang China College of Agriculture Guangxi University Nanning 530005 Guangxi China

Objective To investigate how acetamiprid, a new insecticide, affects the activity of superoxide dismutase （SOD）, catalase （CAT）, and ATPase and the SOD isozyme patterns in two G-bacteria, E. coli K12 anti ***2, and one G^＋ bactemm, B. subtilis. Methods The SOD, CAT, and ATPase specific activities of cell lysates were determined spectrophotometrically at 550 nm, 240 nm, and 660 nm, respectively, with kits A001, A016, and A007. SOD isozyme patterns were detected by native PAGE analysis. Results SOD and CAT activities in the tested bacteria increased significantly in a concentration-dependent manner after different concentrations of acetamiprid were applied. The activity of SOD in B. subtilis and ***2 was stimulated and reached the highest level after treatment with 100 mg/L acetamiprid for 0.5 h. For ***2, there was another stimulation of SOD activity after acetamiprid application for about 8.0 h and the second stimulation was stronger than the first. The stimulation by acetamiprid showed a relative lag for E. coli K12. Acetamiprid seemed to exhibit a similar effect on CAT activity of the two G bacteria and had an evident influence on ATPase activity in the three bacteria within a relatively short period. Only one SOD isozyme was detectable in ***2 and B. subtilis, while different isozyme compositions in E. coli could be detected by native PAGE analysis. Conclusion Acetamiprid causes a certain oxidative stress on the three bacteria which may not only elevate SOD and CAT activities but also generate new SOD isozymes to antagonize oxidative stress. However, this oxidative stress lasts for a relatively short time and does not cause a long-term damage.

关键词： Acetamiprid SOD CAT ATPase Stress response Native PAGE

Iodine catalyzed synthesis of the chromene derivatives in one-pot

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Chinese Chemical Letters 2012年第12期23卷 1347-1351页

作者： Li Yan Zeng mei Fang lv Chun Cai Chemical Engineering College Nanjing University of Science & Technology

Iodine catalyzed one-pot reactions of salicylaldehyde and dimolecular 1H-indene-l,3（2H）-dione, barbituric acids, 4-hydro- xycoumarin, or 4-hydroxy-6-methylpyran-2-one were performed and provided a rapid, convenient and general approach to synthesize the chromene derivatives. 2-（11-Oxo-10,11-dihydroindeno[1,2-b]chromen-10-yl）-lH-indene-1,3（2H）-diones P1-P4 and 10-（4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl）-3-methylpyrano[4,3-b]chromen-1（1OH）-ones P8-P9 were unprecedentedly prepared and structurally identified by NMR and Mass. The confirmation of structure by single crystal X-ray crystallography is reported for P3.

关键词： Chromene Iodine MCRs Salicylaldehyde 1H-Indene-1,3(2H)-dion

One-dimensional Janus Polymeric Vehicles

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Chinese Journal of Polymer Science 2015年第9期33卷 1344-1350页

作者： Dong-mei lv Wei Ni 梁福鑫 Qian Wang Xiao-zhong Qu 杨振忠 State Key Laboratory of Polymer Physics and Chemistry Institute of Chemistry Chinese Academy of Sciences

We herein report a novel approach to fabricate poly（DVB-co-VBC） one-dimentional nanomaterials with varied composition. By adjusting the monomer DVB/VBC ratio and using inert solvents, after internal cavity of the nanotubes disappears and length of the nanotubes is decreased, thus nanorods are achieved. After quaternary ammoniation from the benzyl chloride group, the exterior surface becomes hydrophilic while the interiority preserves hydrophobic. The Janus nanorods can serve as a specific vehicle to selectively collect oils from their aqueous surroundings.

关键词： Poly(DVB-co-VBC) Janus Nanotube Nanorod.

Association of Graves’ disease and Graves’ ophthalmopathy with the polymorphisms in promoter and exon 1 of cytotoxic T lymphocyte associated antigen-4 gene

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第11期7卷 887-891页

作者： ZHANG Qin YANG Yun-mei lv Xue-ying Department of Very Important People the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To investigate the association of Graves’ disease and Graves’ ophthalmopathy with the C/T transition polymorphism at position –318 of promoter and the A/G transition polymorphism at position 49 of exon 1 within cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene. Methods: Thirty-three patients with ophthalmopathy of Graves’ disease, fifty-six Graves’ patients without ophthalmopathy and sixty normal subjects as control were involved in the present case-control study. The polymorphisms were evaluated by polymerase chain reaction fragment length polymorphism (PCR-RFLP). Com-parisons were made of gene frequencies and allele frequencies between the groups. Results: The gene frequencies of CT and allele frequencies of T were much higher in Graves’ patients with ophthalmopathy than that in the group without ophthalmopathy (P=0.020, P=0.019). The gene frequencies of GG and allele frequencies of G in patients with Graves’ disease were significantly increased as compared with control group (P=0.008, P=0.007). The data suggest that smokers with Graves’ disease seemed to be more predisposed to ophthalmopathy than non-smokers (P=0.018). Conclusion: Our results suggest that an allele of T at position –318 of promoter is associated with genetic susceptibility to Graves’ ophthalmopathy while an allele of G at position 49 of exon 1 is associated with genetic susceptibility to Graves’ disease instead. Smoking is believed to be a major risk factor for ophthalmo-pathy.

关键词： Graves' ophthalmopathy Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene Gene frequency Susceptibility gene

Highly Sensitive Temperature Sensor Based on Coupled-Beam AIN-on-Si MEMS Resonators Operating in Out-of-Plane Flexural Vibration Modes

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Research 2023年第1期2022卷 41-49页

作者： Cheng Tu Ming-hong Yang Zi-qiang Zhang Xiu-mei lv Lei Li Xiao-Sheng School of Electronic Science and Engineerng Universy of Eleonic Sciene and Techogy of China Chengdu 611731China Beijing Xingfeng Aerospace Equipment Co. LtdBejing 100854China

This paper reports a type of highly sensitive temperature sensor utilizing AlN-on-Si resonators with coupled-beam structures of double-and triple-ended-tuning-fork(D/TETF).For both resonators,the out-of-plane flexural mode is adopted as it favors the effect of thermal mismatch between the composite layers inherent to the AlN-on-Si structure and thus helps attain a large temperature coeficient of resonant frequency(TCF).The analytical model to calculate TCF values of D/TETF AIN-on-Si resonators is provided,which agrees well with the finite-element simulation and experimental *** resonant temperature sensor is built by closing the loop of the AlN-on-Si resonator,a transimpedance amplifer,a low-pass flter,and a phase shifter to form an oscillator,the output frequency of which shifts proportionally to the ambient *** measured sensitivities of the temperature sensors using D/TETF resonators are better than-1000 ppm/℃in the temperature range of 25℃~60℃,showing great potential to fulfll the on-chip temperature compensation scheme for cofabricated sensors.

关键词： Flex resonant Highly

The effect of dietary tryptophan levels on oxidative stress of liver induced by diquat in weaned piglets

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Journal of Animal Science and Biotechnology 2015年第1期6卷 104-110页

作者： Xiangbing Mao mei lv Bing Yu Jun He Ping Zheng Jie Yu Quyuan Wang Daiwen Chen Animal Nutrition Institute Sichuan Agricultural University Key Laboratory of Animal Disease-Resistance Nutrition Ministry of Education

Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat. A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18, 0.30, and 0A5% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% NaCI solution or diquat （10 mg/kg body weight）. During the first 7 d of trial, increasing dietary tryptophan levels enhanced average daily gain （P = 0.09） and average daily feed intake （P = 0.08）, and decreased the feed efficiency （P 〈 0.05） of piglets. The growth performance was decreased by diquat injection （P 〈 0.05）. Diquat injection also decreased the activities of the superoxide dismutase （SOD） and glutathione peroxidase （GPx） in the plasma and liver （P 〈 0.05）, increased plasma malondialdehyde （MDA）（P 〈 0.05） and urea nitrogen （P 〈 0.05） concentrations, and enhanced MDA concentration （P = 0.09） and tryptophan 2,3-dioxygenase （TDO） activity （P = 0.07） in liver of piglets. Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA （P = 0.06） concentration and the activities of SOD （P = 0.09） and GPx （P = 0.05） of the liver, and plasma urea nitrogen （P = 0.06） concentration in the piglet. There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection （P 〈 0.05）. These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity.

关键词： Antioxidant capacity Diquat Oxidative stress of livers Tryptophan,Weaned piglets

From fundamentals to chemical engineering on oxidative coupling of methane for ethylene production:A review

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Carbon Resources Conversion 2022年第1期5卷 1-14页

作者： Jiao Liu Junrong Yue mei lv Fang Wang Yanbin Cui Zhanguo Zhang Guangwen Xu Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China Institute of Industrial Chemistry and Energy Technology Shenyang University of Chemical TechnologyShenyang 110142LiaoningChina School of Ecology and Environment Beijing Technology and Business UniversityBeijing 100048China

A comprehensive overview is presented to summarize the research works since 1982 on oxidative coupling of methane(OCM),a complex reaction network combining heterogeneous and homogeneous reaction *** on reaction mechanisms and thermodynamics have revealed that the OCM process is highly exothermic and its C2+selectivity and yield is critical in evaluating its commercial *** strategies have been put to enhance C2+selectivity,improve C2+yield and lower reaction *** catalyst MnNa2WO4/SiO2 enables methane activation at a temperature of 800◦C and simultaneously a high C2+selectivity of 70–80%,while the nanowire and La2O3-based catalysts enable to lower the reaction temperature to 200–300◦C and 500◦C,*** engineering aspects have also been dealt in many investigations in order to make the process technically ***,research works on reaction kinetics,reactor selection and reactor operating mode choice have been *** cooling and distributed oxygen feed have been integrated into a multi-stage adiabatic fixed-bed reactor system to suppress the side oxidation reactions and improve the performance of the catalysts towards CH4 conversion and C2+*** review paper proposes employing a circulating reactor system coupled with catalyst fine particles but having little internal diffusion resistance to maximize one-pass C2+selectivity and yield of the OCM reaction and evaluate its industrial application potential.

关键词： Oxidative coupling of methane Methane C2+ Ethylene OCM Reactor

Analysis of Transition Mechanism of Cubic Boron Nitride Single Crystals under High Pressure-High Temperature with Valence Electron Structure Calculation

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Chinese Physics Letters 2019年第1期36卷 10-13页

作者： mei-Zhe lv Bin Xu Li-Chao Cai Feng Jia Xing-Dong Yuan School of Materials Science and Engineering Shandong University School of Materials Science and Engineering Shandong Jianzhu University

The possibilities of hexagonal boron nitride(hBN) and lithium boron nitride(Li_3BN_2) transition into cubic boron nitride(cBN) under synthetic pressure 5.0 GPa and synthetic temperature 1700 K are analyzed with the use of the empirical electron theory of solids and molecules. The relative differences in electron density are calculated for dozens of bi-phase interfaces hBN/cBN, Li_3BN_2/cBN. These relative differences of hBN/cBN are in good agreement with the first order of approximation(<10%), while those of Li_3BN_2/cBN are much greater than 10%.This analysis suggests that Li_3BN_2 is impossible to be intermediate phase but is a catalyst and cBN should be directly transformed by hBN.

关键词： Transition Mechanism Cubic Boron Valence Electron Structure Calculation

Nano-selenium alleviates cadmium-induced cerebellar injury by activating metal regulatory transcription factor 1 mediated metal response

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Animal Nutrition 2022年第4期11卷 402-412页

作者： Shao-Shuai Bi Milton Talukder Hai-Tao Jin mei-Wei lv Jing Ge Cong Zhang Jin-Long Li College of Veterinary Medicine Northeast Agricultural UniversityHarbin 150030China College of Biotechnology and Pharmaceutical Engineering of West Anhui University Lu’an 237012China Department of Physiology and Pharmacology Faculty of Animal Science and Veterinary MedicinePatuakhali Science and Technology UniversityBarishal8210Bangladesh Quality and Safety Institute of Agricultural Products Heilongjiang Academy of Agricultural SciencesHarbin 150010China College of Veterinary Medicine Henan Agricultural UniversityZhengzhou 450002China Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment Northeast Agricultural UniversityHarbin 150030China Heilongjiang Key Laboratory for Laboratory Animals and Comparative Medicine Northeast Agricultural UniversityHarbin 150030China

This study aims to investigate the role of metal regulatory transcription factor 1(MTF1)-mediated metal response in cadmium(Cd)-induced cerebellar injury,and to evaluate the antagonistic effects of nanoselenium(Nano-Se)against Cd toxicity.A total of 80 chicks(1 d old,male,Hy-Line Variety White)were randomly allocated to 4 treatment groups for 3 months:the control group(fed with a basic diet,n=20),the Nano-Se group(basic diet with 1 mg/kg nano-Se 1 mg/kg Nano-Se in basic diet,n=20),the NanoSe+Cd group(basic diet with 1 mg/kg Nano-Se and 140 mg/kg Cd Cl_(2),n=20)and the Cd group(basic diet with 140 mg/kg Cd Cl_(2),n=20).The results of the experiment showed that the Purkinje cells were significantly decreased with their degradation and indistinct nucleoli after Cd ***,exposure to Cd caused a significant accumulation of Cd and ***,the contents of Se,iron,and zinc were decreased,thereby disturbing the metal homeostasis in the *** Cd exposure also resulted in high levels of malondialdehyde(MDA)and down regulation of selenoprotein ***,the expressions of MTF1,metallothionein 1(MT1),MT2,zinc transporter 3(ZNT3),ZNT5,ZNT10,zrt,irt-like protein 8(ZIP8),ZIP10,transferrin(TF),ferroportin 1(FPN1),ATPase copper transporting beta(ATP7B),and copper uptake protein 1(CTR1)were inhibited by Cd ***,all these changes were significantly alleviated by the supplementation of *** study proved that Cd could disorder metal homeostasis and induce oxidative stress,whereas Nano-Se could relieve all these negative effects caused by Cd via activating the MTF1-mediated metal response in the cerebellum of chicken.

关键词： Nano-selenium Cadmium Selenoprotein transcriptome MTF1-mediated metal response Cerebellar injury