检索结果-南通市图书馆

Oxidative stress and DNA damages induced by cadmium accumulation

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2007年第5期19卷 596-602页

作者： lin ai-jun ZHANG Xu-hong CHEN Mei-mei CAO Qing Department of Environmental Science and Engineering Beijing University of Chemical Technology Beijing 100029 China Department of Soil Environmental Sciences Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Beijing City University Beijing 100083 China

Experimental evidence shows that cadmium （Cd） could induce oxidative stress and then causes DNA damage in animal cells, however, whether such effect exists in plants is still unclear. In the present study, Vicia faba plants was exposed to 5 and 10 mg/L Cd for 4 d to investigate the distribution of Cd in plant, the metal effects on the cell lipids, antioxidative enzymes and DNA damages in leaves. Cd induced an increase in Cd concentrations in plants. An enhanced level of lipid peroxidation in leaves and an enhanced concentration of H2O2 in root tissues suggested that Cd caused oxidative stress in Vicia faba. Compared with control, Cd-induced enhancement in superoxide dismutase activity was significant at 5 mg/L than at 10 mg/kg in leaves, by contrast, catalase and peroxidaseactivities were significantly suppressed by Cd addition. DNA damage was detected by neutral/neutral, alkaline/neutral and alkaline/alkaline Comet assay. Increased levels of DNA damages induced by Cd occurred with reference to oxidative stress in leaves, therefore, oxidative stress induced by Cd accumulation in plants contributed to DNA damages and was possibly an important mechanism of Cd-phytotoxicity in Vicia faba plants.

关键词： Cd Vicia faba oxidative stress DNA damage

Biodegradation of n-hexadecane by bacterial strains B1 and B2 isolated from petroleum-contaminated soil

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2012年第9期55卷 1968-1975页

作者： LIU Tao WANG FengHua GUO LanPing LI XiaoLiang YANG XiaoJin lin ai jun State Key Laboratory of Pollution Control and Resource Reuse(Tongji University) Shanghai 200092China Experimental Teaching Center of Environmental Science and Engineering Tongji UniversityShanghai 200092China Department of Environmental Science and Engineering Beijing university of Chemical TechnologyBeijing 100029China Department of Soil Environmental Sciences Research Centerfor Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Institute of Chinese Material Medical China Academy of Chinese Medical SeiencesBeijing 100700China Chinese Academy for Environmental Planning Beijing 100012China

Two hydrocarbon-biodegrading bacterial strains, B1 and B2, were isolated from petroleum-contaminated soil collected from Tianjin, China. The strains were identified as Pseudomonas aeruginosa （B 1） and Acinetobacter junii （B2）. The degradation rate of n-hexadecane by BI and B2 reached 96% and 78% respectively after 7 days, though the strains employed different mechanisms of degradation. The results showed that B2 was not able to use glucose as carbon source. B 1 could produce glyco- lipid surfactants using glucose as the carbon source, according to the results of blue agar plate analysis and thin layer chroma- tography （TLC）, and the bacterial culture of B 1 had a high oil discharge and emulsification activity. Both B I and B2 could produce biosurfactants with hexadecane as the sole carbon source, but their modes of action were different. The carbon source was found to affect the cell surface hydrophobicity. Cell surface hydrophobicity was poor with glucose as the carbon source, but enhanced when hexadecane was used as the carbon source.

关键词： hexadecane biosurfactant hydrophobicity emulsification bacteria

Effects of Glomus mosseae on the toxicity of heavy metals to Vicia faba

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2006年第4期18卷 721-726页

作者： ZHANG Xu-hong lin ai-jun CHEN Bao-dong WANG You-shan SMITH Sally E SMITH F Andrew Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Department of Environmental Engineering Beijing University of Chemical Technology Beijing 100029 China Lab of Soil and Microbe Department of Plant Nutrition and Resource Agriculture and Forestry Academy of Beijing Beijing 100089 China Soil and Land Systems School of Earth and Environmental Sciences The University of Adelaide Adelaide South Australia 5005 Australia

A glasshouse pot experiment was conducted to investigate effects of the arbuscular mycorrhizal fungus Glomus mosseae on the growth of Vicia faba and toxicity induced by heavy metals （HMs）（Cu, Zn, Pb and Cd） in a field soil contaminated by a mixture of these metals. There was also uninoculation treatment （NM） simultaneously. Mycorrhizal （GM） plants have significantly increased growth and tolerance to toxicity induced by heavy metals compared with NM plants. P uptake was significantly increased in GM plants. Mycorrhizal symbiosis reduced the transportation of HMs fi＇om root to shoot by immobilizing HMs in the mycorrhizal, shown by increasing the ratios of HMs from root to shoot. Oxidative stress, which can induce DNA damage, is an important mechanism of heavy metal toxicity. GM treatment decreased oxidative stress by intricating antioxidative systems such as peroxidases and non-enzymic systems including soluble protein. The DNA damage induced by heavy metals was detected using comet assay, which showed DNA damage in the plants was decreased by the GM treatment.

关键词： arbuscular mycorrhizal fungi (AMF) metal contamination metal toxicity DNA damage

在线全文

学校读者我要写书评

暂无评论

新闻传播中的隐私权保护问题

新闻大学 2005年第1期 33-37页

作者：林爱珺复旦大学

一个世纪以前,哈佛大学法学院教授路易斯·布兰蒂斯(Louis ***)和赛缪尔·沃伦(Samuel ***)在1890年第四期哈佛大学的上发表了一篇著名的论文,指责新闻传播有时会侵犯'个人私生活的神圣界限',[1]在信息时代的今天,新闻传播业快速发展,... 详细信息

一个世纪以前,哈佛大学法学院教授路易斯·布兰蒂斯(Louis ***)和赛缪尔·沃伦(Samuel ***)在1890年第四期哈佛大学的上发表了一篇著名的论文,指责新闻传播有时会侵犯'个人私生活的神圣界限',[1]在信息时代的今天,新闻传播业快速发展,隐私权问题越来越受到了人们的迫切关注.

关键词：新闻传播隐私权保护新闻采访新闻报道立法

Synergistic effects of Pleistocene geological and climatic events on complex phylogeographic history of widespread sympatric species of Megaloptera in East Asia

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2024年第5期45卷 1131-1146页

作者： ai-Li lin Ming-Ming Zou Li-jun Cao Fumio Hayashi Ding Yang Xing-Yue Liu Department of Entomology China Agricultural UniversityBeijing 100193China Sanya Institute of China Agricultural University SanyaHainan 572025China International Joint Laboratory of Taxonomy and Systematic Evolution of Insecta Henan Institute of Science and TechnologyXinxiangHenan 453003China Institute of Plant and Environmental Protection Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Department of Biology Tokyo Metropolitan UniversityHachioji-shiTokyo 192-0397Japan

Unraveling the phylogeographic histories of species remains a key endeavor for comprehending the evolutionary processes contributing to the rich biodiversity and high endemism found in East *** this study,we explored the phylogeographic patterns and demographic histories of three endemic fishfly and dobsonfly species(Neochauliodes formosanus,Protohermes costalis,and Neoneuromus orientalis)belonging to the holometabolan order *** species,which share a broad and largely overlapping distribution,were analyzed using comprehensive mitogenomic *** findings revealed a consistent influence of vicariance on the population isolation of *** and *** between Hainan,Taiwan,and the East Asian mainland during the early Pleistocene,potentially hindering subsequent colonization of the later diverged *** to these ***,we unveiled the dual function of the major mountain ranges in East Asia,serving both as barriers and conduits,in shaping the population structure of all three ***,we demonstrated that these co-distributed species originated from Southwest,Southern,and eastern Central China,respectively,then subsequently migrated along multi-directional routes,leading to their sympatric distribution on the East Asian ***,our results highlighted the significance of Pleistocene land bridges along the eastern coast of East Asia in facilitating the dispersal of mountain-dwelling insects with low dispersal ***,this study provides novel insight into the synergistic impact of Pleistocene geological and climatic events in shaping the diversity and distribution of aquatic insects in East Asia.

关键词： Comparative phylogeography Island biogeography Pleistocene glaciation Corydalidae East Asia

Study of primordial deuterium abundance in Big Bang nucleosynthesis

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-lin Shen Jian-jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Ubiquitin-specific protease 21 promotes tumorigenicity and stemness of colorectal cancer by deubiquitinating and stabilizing ZEB1

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第3期16卷 1006-1018页

作者： jun-jun lin Ye-Cai Lu Department of Gastrointestinal Surgery Chaohu Hospital of Anhui Medical UniversityChaohu 238000Anhui ProvinceChina

BACKGROUND Colorectal cancer(CRC)is one very usual tumor together with higher death ***-specific protease 21(USP21)has been confirmed to take part into the regulation of CRC progression through serving as a ***,the promotive function of USP21 has also discovered in the progression of ***1 has illustrated to be modulated by USP7,USP22 and USP51 in ***,the regulatory functions of USP21 on ZEB1 in CRC progression need more *** To investigate the relationship between USP21 and ZEB1 in CRC *** The mRNA and protein expressions were assessed through RT-qPCR,western blot and IHC *** interaction between USP21 and ZEB1 was evaluated through Co-IP and GST pull down *** cell proliferation was detected through colony formation *** cell migration and invasion abilities were determined through Transwell *** stemness was tested through sphere formation *** tumor growth was evaluated through in vivo mice *** In this work,USP21 and ZEB1 exhibited higher expression in CRC,and resulted into poor ***,the interaction between USP21 and ZEB1 was further *** was demonstrated that USP21 contributed to the stability of ZEB1 through modulating ubiquitination *** addition,USP21 streng-thened cell proliferation,migration and stemness through regulating *** last,through in vivo assays,it was illustrated that USP21/ZEB1 axis aggravated tumor *** For the first time,these above findings manifested that USP21 promoted tumorigenicity and stemness of CRC by deubiquitinating and stabilizing *** discovery suggested that USP21/ZEB1 axis may provide novel sights for the treatment of CRC.

关键词： Ubiquitin-specific protease 21 ZEB1 Stemness Colorectal cancer

Investigation on the influence of vortex generator on particle resuspension

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu jun-Li lin Jin-Han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-lin Li Qing-Qing Zhang lin Dong Wen-jun Zhang Li-Li lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst