检索结果-南通市图书馆

Metal concentrations and mycorrhizal status of plants colonizing copper mine tailings: potential for revegetation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2005年第Z1期48卷 156-164页

作者： christie peter Department of Agricultural and Environmental Science The Queen's University of Belfast Newforge Lane Belfast BT9 5PX Northern Ireland UK

A field survey of metal concentrations and mycorrhizal status of plants growing on copper mine tailings was conducted in Anhui Province, China. Available phosphorus and organic matter in the tailings were very low. High concentrations of Pb, Zn, As and Cd as well as Cu were observed on some sites. The dominant plants growing on mine tailings belonged to the families Gramineae and Compositae, and the most widely distributed plant species were Imperata cylindrica, Cynodon dactylon and Paspalum distichum. Coreopsis drummondii also grew well on the arid sites but not on wet sites. Very low or zero arbuscular mycorrhizal (AM) fungal colonization was observed in most of the plants, but extensive mycorrhizal colonization was recorded in the roots of C. drummondii and C. dactylon. Metal concentrations in plant tissues indicated that *** and P. distichum utilized avoidance mechanisms to survive at high metal concentrations. The investigation suggests that remediation and revegetation of heavy metal contaminated sites might be facilitated by selection of tolerant plant species. Isolation of tolerant AM fungi may also be warranted.

关键词： phytoremediation, revegetation, heavy metals, copper mine tailings, arbuscular mycorrhiza.

Effect of Silicon on Growth, Physiology, and Cadmium Translocation of Tobacco (Nicotiana tabacum L.) in Cadmium-Contaminated Soil

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2018年第4期28卷 680-689页

作者： LU Yingang MA Jun TENG Ying HE Juny peter christie ZHU Lingjia REN Wenjie ZHANG Manyun Shiping DENG College of Agriculture Guizhou University Guiyang 550025 China College of Materials and Chemistry Tongren University Tongren 554300 China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Department of Plant and Soil Sciences Oklahoma State University Stillwater OK 74078 (USA)

Silicon(Si) offers beneficial effect on plants under cadmium(Cd) stress such as promoting plant growth and increasing resistance to heavy metal toxicity. In this study, a pot experiment was performed to study the role of Si in alleviating Cd toxicity in tobacco(Nicotiana tabacum L.) plants on a yellow soil taken from Guiyang, China. Nine treatments consisting of three concentrations of Cd(0, 1, and 5 mg kg^(-1)) together with three Si levels(0, 1, and 4 g kg^(-1)) were established. Plant growth parameters, Cd concentration,and the malondialdehyde(MDA), chlorophyll, and carotenoid contents were determined 100 d after transplanting of tobacco *** of exogenous Si enhanced the growth of tobacco plants under Cd stress. When 5 mg kg^(-1) Cd was added, Si addition at 1 and 4 g kg^(-1) increased root, stem, and leaf biomass by 26.1%–43.3%, 33.7%–43.8%, and 50.8%–69.9%, respectively, compared to Si addition at 0 g kg^(-1). With Si application, the transfer factor of Cd in tobacco from root to shoot under both 1 and 5 mg kg^(-1) Cd treatments decreased by 21%. The MDA contents in the Si-treated tobacco plants declined by 5.5%–17.1% compared to those in the non-Si-treated plants, indicating a higher Cd tolerance. Silicon application also increased the chlorophyll and carotenoid contents by 33.9%–41% and 25.8%–47.3% compared to the Cd only treatments. Therefore, it could be concluded that Si application can alleviate Cd toxicity to tobacco by decreasing Cd partitioning in the shoots and MDA levels and by increasing chlorophyll and carotenoid contents, thereby contributing to lowering the potential health risks of Cd contamination.

关键词：植物生长烟草土壤污染生理学类胡萝卜素镉硅

Microbial remediation of a pentachloronitrobenzene-contaminated soil under Panax notoginseng: A field experiment

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2020年第4期30卷 563-569页

作者： Ning ZHANG Dong GUO Ye ZHU Xiaomi WANG Lingjia ZHU Fang LIU Ying TENG peter christie Zhengao LI Yongming LUO College of Resource and Environmental Engineering Guizhou UniversityGuiyang 550025(China) Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) Infinitus(China)Co. LTDJiangmen 529156(China) Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003(China)

Pentachloronitrobenzene(PCNB)is an organochlorine fungicide that is mainly used in the prevention and control of diseases in crop *** removal is used as a promising method for in-situ removal of many organic pesticides and pesticide residues.A short-term field experiment(1 year)was conducted to explore the potential role of a PCNB-degrading bacterial isolate,Cupriavidus ***-85,in the remediation of a PCNB-contaminated soil on which Panax notoginseng was *** following three treatments were used:i)control soil amended with wheat bran but without YNS-85,ii)soil with 0.15 kg m-2of solid bacterial inoculum(A),and iii)soil with 0.30 kg m-2of solid bacterial inoculum(B).The removal of soil PCNB during the microbial remediation was monitored using gas *** catalase and fluorescein diacetate(FDA)esterase activities were determined using *** addition,cultivable bacteria,fungi,and actinomycetes were counted by plating serial dilutions,and the microbial biodiversity of the soil was analyzed using *** 1 year of in-situ remediation,the soil PCNB concentrations decreased significantly by 50.3%and 74.2%in treatments A and B,respectively,when compared with the uninoculated *** soil catalase activity decreased in the presence of the bacterial isolate,the FDA esterase activity decreased in treatment A,but increased in treatment *** significant changes in plant biomass,diversity of the soil microbial community,or physicochemical properties of the soil were observed between the control and inoculated groups(P<0.05).The results indicate that Cupriavidus ***-85 is a potential candidate for the remediation of PCNB-contaminated soils under ***.

关键词： Cupriavidus sp.YNS-85 enzyme activities in-situ remediation PCNB removal soil

Evidence for niche differentiation of nitrifying communities in grassland soils after 44 years of different field fertilization scenarios

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2020年第1期30卷 87-97页

作者： Zhongjun JIA Xue ZHOU Weiwei XIA Dario FORNARA Baozhan WANG Elizabeth Anne WASSON peter christie Martin F.POLZ David D.MYROLD State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098(China) Jiangsu Key Laboratory of Agricultural Meteorology College of Applied MeteorologyNanjing University of Information Science and TechnologyNanjing 210044(China Agri-Food and Biosciences Institute Belfast BT95PX(UK) Department of Civil and Environmental Engineering Massachusetts Institute of TechnologyCambridge MA 02139(USA) Department of Crop and Soil Science Oregon State UniversityCorvallis OR 97331(USA)

Long-term nitrogen(N)fertilization imposes strong selection on nitrifying communities in agricultural soil,but how a progressively changing niche affects potentially active nitrifiers in the field remains poorly *** a 44-year grassland fertilization experiment,we investigated community shifts of active nitrifiers by DNA-based stable isotope probing(SIP)of field soils that received no fertilization(CK),high levels of organic cattle manure(HC),and chemical N fertilization(CF).Incubation of DNA-SIP microcosms showed significant nitrification activities in CF and HC soils,whereas no activity occurred in CK *** 44 years of inorganic N fertilization selected only 13C-ammonia-oxidizing bacteria(AOB),whereas cattle slurry applications created a niche in which both ammonia-oxidizing archaea(AOA)and AOB could be *** analysis indicated that Nitrosospira sp.62-like AOB dominated inorganically fertilized CF soils,while Nitrosospira sp.41-like AOB were abundant in organically fertilized HC *** 13C-AOA in HC soils were affiliated with the 29i4 *** 13C-nitrite-oxidizing bacteria(NOB)were dominated by both Nitrospira-and Nitrobacter-like communities in CF soils,and the latter was overwhelmingly abundant in HC *** 13C-labeled nitrifying communities in SIP microcosms of CF and HC soils were largely similar to those predominant under field *** results provide direct evidence for a strong selection of distinctly active nitrifiers after 44 years of different fertilization regimes in the *** findings imply that niche differentiation of nitrifying communities could be assessed as a net result of microbial adaption over 44 years to inorganic and organic N fertilization in the field,where distinct nitrifiers have been shaped by intensified anthropogenic N input.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria community shift long-term fertilization nitrite-oxidizing bacteria nitrogen enrichment stable isotope probing microcosm

Collembolans accelerate the dispersal of antibiotic resistance genes in the soil ecosystem

在线全文

学校读者我要写书评

暂无评论

Soil Ecology Letters 2019年第1期1卷 14-21页

作者： Dong Zhu Hong-Tao Wang Fei Zheng Xiao-Ru Yang peter christie Yong-Guan Zhu Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences 19A Yuquan RoadBeijing 100049China Agri-Environment Branch Agri-Food and Biosciences InstituteBelfast BT95PXUnited Kingdom State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Soils have become an important sink for antibiotic resistance genes(ARGs).To better understand the impacts of ARGs on the soil ecosystem,the transport of ARGs is a basic *** far,however,the role of soil animals in the dispersal of ARGs is not ***,two treatments(without collembolans and with collembolans)were established,each treatment included unamended and manure-amended soil,and soil samples were collected at 14,28 and 56 days after *** effects of the collembolan Folsomia candida on dispersal of ARGs in the soil ecosystem were explored using high-throughput qPCR combined with Illumina *** the culture time increased,more shared ARGs and OTUs were detected between the unamended and manured soil,especially in the treatment with ***,aminoglycoside and MLSB genes may have been more readily transported by the *** the 28th day after incubation,a high abundance of mobile genetic elements(MGEs)was found in the treatment with *** results clearly reveal that collembolans can accelerate the dispersal of ARGs in the soil *** analysis and the Mantel test both indicate that soil bacterial communities were significantly correlated with ARG ***,partial redundancy analysis indicates that soil bacterial communities can explain 41.28% of the variation in *** results suggest that the change of soil microbial community have an important contribution to the dispersal of ARGs by the collembolan.

关键词： Soil fauna High-throughput qPCR Microbial community Mobile genetic elements Lllumina sequencing

Experimental investigation on slip conditions during thread rolling with flat dies

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

Friction 2024年第1期12卷 136-143页

作者： Stefan VOLZ peter GROCHE Institute for Production Engineering and Forming Machines Technical University DarmstadtOtto-Berndt Straße 2Darmstadt 64287Germany

The process design of flat die rolling operations can be a tedious and costly process due to the challenges posed by small process *** this work,an effort is made to closely investigate and understand the process limits caused by excessive slippage of the *** measurements are carried out to capture the characteristics of excessive slippage and the influence of the stroke rate and the tribological system on this process *** differences in slippage were observed,depending on the tribological *** systems with polymer based lubricants showed excessive slippage at low stroke rates,systems using oil or no lubricant endured higher stroke rates before process limits were *** optical measurements revealed three major forms of slippage:successful rolling without slippage,failure due to excessive slippage at process start,and failure due to excessive slippage at around one workpiece rotation.

关键词： rolling incremental forming thread rolling slippage profile rolling

Skeletal muscle as a molecular and cellular biomarker of disease progression in amyotrophic lateral sclerosis:a narrative review

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

Neural Regeneration Research 2024年第4期19卷 747-753页

作者： peter H.King Department of Neurology and Center for Neurodegeneration and Experimental Therapeutics The University of Alabama at BirminghamBirminghamALUSA Birmingham Veterans Affairs Medical Center BirminghamALUSA

Amyotrophic lateral sclerosis is a fatal multisystemic neurodegenerative disease with motor neurons being a primary *** progressive weakness is a hallmark feature of amyotrophic lateral sclerosis,there is considerable heterogeneity,including clinical presentation,progression,and the underlying triggers for disease *** on longitudinal studies with families harboring amyotrophic lateral sclerosis-associated gene mutations,it has become apparent that overt disease is preceded by a prodromal phase,possibly in years,where compensatory mechanisms delay symptom *** 85-90%of amyotrophic lateral sclerosis is sporadic,there is a strong need for identifying biomarkers that can detect this prodromal phase as motor neurons have limited capacity for *** Food and Drug Administration-approved therapies work by slowing the degenerative process and are most effective early in the *** muscle,including the neuromuscular junction,manifests abnormalities at the earliest stages of the disease,before motor neuron loss,making it a promising source for identifying biomarkers of the prodromal *** accessibility of muscle through biopsy provides a lens into the distal motor system at earlier stages and in real *** advent of“omics”technology has led to the identification of numerous dysregulated molecules in amyotrophic lateral sclerosis muscle,ranging from coding and non-coding RNAs to proteins and *** technology has opened the door for identifying biomarkers of disease activity and providing insight into disease mechanisms.A major challenge is correlating the myriad of dysregulated molecules with clinical or histological progression and understanding their relevance to presymptomatic phases of *** are two major goals of this *** first is to summarize some of the biomarkers identified in human amyotrophic lateral sclerosis muscle that have a clinicopathological correlation with disease activi

关键词： amyotrophic lateral sclerosis biomarkers clinicopathological correlation disease progression muscle biomarkers neurogenic atrophy neuromuscular junction non-coding RNAs presymptomatic stages skeletal muscle SOD1G93A mouse model

EDTA、DTPA、柠檬酸和FeCl3对污染稻田土壤镉铅的去除及土壤肥力的影响（英文）

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2019年第11期26卷 2987-2997页

作者：梁芳郭朝晖门姝慧肖细元彭驰吴龙华 peter christie School of Metallurgy and Environment Central South UniversityChangsha 410083China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

潜在有害金属镉和铅对水稻的安全生产有着重要意义.本文对比研究了EDTA、DTPA、柠檬酸和FeCl3对镉和铅的去除能力以及对土壤肥力的影响.结果表明,选取固液比1:10振荡30 min用10 g/LEDTA(pH 5)可去除59%Cd和63%Pb,而在同等条件下,5 g/L D... 详细信息

潜在有害金属镉和铅对水稻的安全生产有着重要意义.本文对比研究了EDTA、DTPA、柠檬酸和FeCl3对镉和铅的去除能力以及对土壤肥力的影响.结果表明,选取固液比1:10振荡30 min用10 g/LEDTA(pH 5)可去除59%Cd和63%Pb,而在同等条件下,5 g/L DTPA可去除52%Cd和51%***的土壤淋出液含58%酸可提取态和可还原态Cd,49%酸可提取态和可还原态Pb,DTPA淋出液中含53%和41%.土壤pH值、阳离子交换量、有机质、土壤有效磷变化较小.而柠檬酸和氯化铁仅对Cd淋洗有效,且淋洗后土壤pH值下降显著.研究表明EDTA和DTPA可以作为潜在有害金属污染稻田土壤净化的合适淋洗剂.

关键词：污染稻田土壤土壤淋洗潜在有害金属形态分析土壤肥力

A product version of the Hilton-Milner-Frankl theorem

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2024年第2期67卷 455-474页

作者： peter Frankl Jian Wang Alfréd Rényi Institute of Mathematics Hungarian Academy of SciencesBudapest H-1053Hungary Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Two families F and G of k-subsets of {1, 2,..., n} are called non-trivial cross t-intersecting if|F ∩ G|≥t for all F ∈ F, G ∈ G and | ∩ {F : F ∈ F}| < t, | ∩ {G : G ∈ G}| < t. In the present paper,we determine the maximum product of the sizes of two non-trivial cross t-intersecting families of k-subsets of{1, 2,..., n} for n≥4(t + 2)2k2, k≥5, which is a product version of the Hilton-Milner-Frankl theorem.

关键词： extremal set theory cross t-intersecting family product version non-trivial