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Distribution,risk evaluation,and source analysis of the heavy metals in the sediment deposition of the lower Shichuanhe River,Shaanxi,China

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Acta Geochimica 2023年第5期42卷 832-844页

作者： Chenhui Hou Caixia feng Shen Liu Department of Geology Northwest UniversityXi’an 710069China

In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in Xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of the pollution levels of this area, hope to provide guidance on agricultural production activities in this region. The results show that the heavy metal elements in this area are mainly concentrated at the Qinghe River and Shichuanhe River confluences. Furthermore, the element contents are higher than that of the background levels of the continental crust(UCC) and close to the background levels of the soil from Shaanxi Province;the two most enriched elements are Cd and As, with contents of 0.79 and 22.7 mg·kg-1, respectively, and their contents are 3.8 and 1.72 times higher than that of the background values. Herein, the heavy metal pollution assessment methods applied indicated that Cd and As are the two most abundant pollutant elements in the area’s soils. As has a peak geo-accumulation index value of 3, and the pollution level is high, while Cd exhibits high potential ecological risks due to its high toxicity(potential risk index of 143) and an active fraction of more than 64%.In addition, a principal component analysis and hierarchical cluster analysis study showed that there are two sources of the heavy metals in this area. The Zn, As, Ni, Cu, Pb,and Cr are mainly from natural sources, and the Cd likely comes from a discharge of untreated agricultural wastewater in the region. The Cd which poses a high potential risk and mainly results from human activities, needs to be further monitored.

关键词： Distribution Risk evaluation Source analysis Heavy metals Sediment Ecological risk

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Words of the Editor-in-Chief——Academic discussion is an effective measure to promote scientific development

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Journal of Palaeogeography 2017年第3期6卷 219-223页

作者： Zeng-Zhao feng China University of Petroleum (Beijing)

Van Loon et al.＇s paper ＂The response of stromatolites to seismic shocks： Tomboliths from the Palaeoproterozoic Chaibasa Formation, E India＂ with a new term ＂tomboliths＂ and original viewpoints should be published, but some contents need to be discussed. Shanmugam＇s paper ＂The response of stromatolites to seismic shocks： Tomboliths from the Palaeoproterozoic Chaibasa Formation, E India： Discussion and liquefaction basics＂ pointed out some queries and problems about Van Loon et al.＇s paper. It is an academic discussion paper and should be published as well. However, some main problems, such as the new term＂tomboliths＂ and its origin of seismic shocks, ＂whether stromatolites or tomboliths are soft-sediment deformation structures or not＂, etc., also need to be discussed. Academic discussion is an effective measure to promote scientific development. The more thorough academic discussions are carried out regarding academic problems, the more scientific facts and truths will become clear. All participants in this discussion are contributors. It is active to carry out the policy of ＂A hundred flowers blossom and a hundred schools of thought contend＂ by our Journal of Palaeogeography.

关键词： Tomboliths Seismic shocks Stromatolitic bioclasts Stromatolitic gravels Stromatolites Softsediment deformation structures(SSDS) Academic discussion A hundred flowers blossom and a hundred schools of thought contend Geological practice

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Avoidance of Linkage Drag Between Blast Resistance Gene and the QTL Conditioning Spikelet Fertility Based on Genotype Selection Against Heading Date in Rice

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Rice science 2009年第1期16卷 21-26页

作者： LIU wen-qiang FAN Ye-yang CHEN Jie SHI Yong-feng Wu Jian-li Chinese National Center for Rice Improvement/State key Laboratory for Rice Biology China National Rice Research Institute Hangzhou 310006 China

Previous study showed that a linkage drag between a blast resistance gene Pi25（t） and QTLs conditioning spikelet fertility （qSF-6） and number of filled grains per panicle （qNFGP-6） was detected on the short arm of chromosome 6. A larger population was used for further verification, and the results confirmed the linkage drag between the blast resistance gene and QTL conditioning spikelet fertility, other than QTL conditioning number of filled grains per panicle. Breakdown or avoidance of the linkage drag could be achieved by selection against the genotype background of a heading-date gene （qHD-7） that resided in the region between RM2 and RM214 on chromosome 7. For further validation, two lines with almost identical genotypes on all chromosomal regions except the Pi25（t） region on chromosome 6 were chosen to develop a new population The results showed that qSF-6 could be further subdivided into qSF-6-1 and qSF-6-2. When the genotype of the region between RM2 and RM214 was from rice variety Zhong 156, the linkage drag between Pi25（t） and qSF-6-2 was detected and the allele of qSF-6-2 from rice variety Gumei 2 reduced the spikelet fertility. When the genotype of the region between RM2 and RM214 was from Gumei 2, no linkage drag was detected. This indicates that the linkage drag between the blast resistance gene and the QTL conditioning spikelet fertility could be broken down or avoided under a certain background genotype selection against heading-date and provides a marker aided solution for high level of blast resistance and yield breeding in rice and other crops as well.

关键词： rice (Oryza sativa) linkage drag blast resistance quantitative trait locus spikelet fertility heading date

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Microstructure evolution and deformation mechanism of amorphous/crystalline high-entropy-alloy composites

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Journal of Materials Science & Technology 2020年第19期54卷 14-19页

作者： Jia Li Haotian Chen Hui feng Qihong Fang Yong Liu feng Liu Hong Wu Peter K Liaw State key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China State key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA

High-entropy amorphous alloys present high hardness,but low tensile ***,deformation behavior of the amorphous/crystalline Fe Co Cr Ni high-entropy alloy(HEA)composite prepared by the previous experiment is investigated using atomic *** result shows the partial dislocations in the crystal HEA layer,and the formation of shear bands in the amorphous HEA layer occurs after *** strength of the amorphous/crystalline HEA composite reduces with increasing the thickness of the amorphous layer,agreeing with the previous *** coupled interaction between the crystal plasticity and amorphous plasticity in amorphous/crystalline HEA composites results in a more homogeneous redistribution of plastic deformation to cause interface hardening,due to the complex stress field in the amorphous *** current findings provide the insight into the deformation behavior of the amorphous/crystalline HEA composite at the nanoscale,which are useful for optimizing the structure of the HEA composite with high strength and good plasticity.

关键词： High-entropy alloy Amorphous/crystalline composite Deformation behavior Strengthening mechanism Molecular dynamics

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Characterization of flavonoids in Millettia nitida var. hirsutissima by HPLC/DAD/ESI-MS^n

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Journal of Pharmaceutical Analysis 2012年第1期2卷 35-42页

作者： Min Ye, wen-Zhi Yang, ke-Di Liu, Xue Qiao, Bei-Jia Li, Jun Cheng, Jie feng, De-An Guo, Yu-Ying Zhao State key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Beijing 100191, China State key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University 38 Xueyuan Road Beijing 100191 China.

Millettia nitida var. hirsutissima is a Chinese herbal medicine used for the treatment of gynecological diseases. An HPLC/DAD/ESI-MSn method was established for the rapid separation and characterization of bioactive flavonoids in M. nitida var. hirsutissima. A total of 32 flavonoids were detected, of which 14 compounds were unambiguously characterized by comparing their retention time, UV, and MS spectra with those of the reference standards, and the others were tentatively identified based on their tandem mass spectrometry fragmentation data obtained in the negative ionization mode on line. Nineteen of these compounds characterized were reported from this plant for the first time.

关键词： HPLC/DAD/ESI-MSn Millettia nitida var. hirsutissima Mass spectrometry Flavonoids

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Genetic dissection of drought resistance for trait improvement in crops

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The Crop Journal 2023年第4期11卷 975-985页

作者： Shengxue Liu Hongwei Wang feng Qin College of Biological Sciences China Agricultural UniversityBeijing 100193China Agricultural College Yangtze UniversityJingzhou 434025HubeiChina

Reliance on agriculture for food security is a constant in all modern *** climate change and population growth have put immense pressure on sustainable agriculture,exacerbating the effects of environmental *** is one of the most pressing abiotic stresses that farmers face,presenting an annual threat to crop growth and *** have evolved extensive morphological,physiological,and molecular mechanisms to combat drought *** resistance is a polygenic trait,controlled by a complex genetic network and an array of genes working together to ensure plant *** studies have aimed at dissecting the genetic mechanisms underlying drought *** studies using linkage and association mapping have made progress in identifying genetic variations that affect drought-resistance *** loci may potentially be engineered by genetic transformation and genome editing aimed at developing new,stress-resistant crop *** we summarize recent progress in elucidating the genetic basis of crop drought ***-breeding technologies such as marker-assisted selection,genome selection,gene transformation,and genome editing are currently employed to develop drought-resistant germplasm in a variety of *** advances in basic research and crop biotechnology covered in this review will facilitate delivery of drought-resistant crops with unprecedented efficiency.

关键词： Drought resistance QTL GWAS Molecular breeding

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Exhausted T cells and epigenetic status

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Cancer Biology & Medicine 2020年第4期17卷 923-936页

作者： Ziqing Zeng feng Wei Xiubao Ren Department of Immunology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin's Clinical Research Center for CancerKey Laboratory of Cancer Immunology and BiotherapyTianjin 300060China Department of Biotherapy Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin's Clinical Research Center for CancerKey Laboratory of Cancer Immunology and BiotherapyTianjin 300060China

Exhausted T cells are a group of dysfunctional T cells,which are present in chronic infections or *** most significant characteristics of exhausted T cells are attenuated effector cytotoxicity,reduced cytokine production,and upregulation of multiple inhibitory molecular receptors(e.g.,PD-1,TIM-3,and LAG-3).The intracellular metabolic changes,altered expression of transcription factors,and a unique epigenetic landscape constitute the exhaustion ***,researchers have made progress in understanding exhausted T cells,with the definition and identification of exhausted T cells changing from phenotypebased to being classified at the transcriptional and epigenetic *** studies have revealed that exhausted T cells can be separated into two subgroups,namely TCF1^(+)PD-1^(+)progenitor-like precursor exhausted cells and TCF1-PD-1^(+)terminally differentiated exhausted T ***,the progenitor-like precursor cell population may be a subset of T cells that can respond to *** have also found that TOX initiates and dominates the development of exhausted T cells at the transcriptional and epigenetic *** also maintains T cell survival and may affect decisions regarding treatment *** this review,we discuss the latest developments in T cell exhaustion in regards to definitions,subpopulations,development mechanisms,differences in diverse diseases,and treatment prospects for exhausted T ***,we hypothesize that the epigenetic state regulated by TOX might be the key point,which can determine the reversibility of exhaustion and the efficacy of immunotherapy.

关键词： T cell exhaustion TOX tumor immunity epigenetic landscape immunotherapy

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Comparison of microstructures and mechanical properties between forging and rolling processes for commercially pure titanium

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Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1939-1946页

作者：徐春朱文峰上海应用技术学院材料科学与工程系上海201418 同济大学机械工程学院上海200092

In order to reveal the differences caused by forging and rolling process for titanium ingots, hot compression behavior, mechanical properties and the microstructures of forged billets and rolled ones were investigated in detail using Gleeble-1500 thermal mechanical simulator, universal testing machine and optical microscope （OM）. The compression deformation experimental data of commercially pure titanium （CP-Ti） were mapped to be a T vs lg diagram in which data fall into three distinct regions, i.e., three-stage work hardening, two-stage work hardening and flow softening, which can be separated by border lines at 17.5 and 15.4 for lg Z, where Z represents the Zener-Hollomon parameter. The deformation twin is found to have higher Z-value corresponding to the work hardening region. The differences in microstructures and mechanical properties for two kinds of billets indicate that forged billet consists of deformation twins and some twin intersections, and many twins cross the grain boundaries. However, nearly no twins can be seen in the microstructure of billet formed by rolling under optical microscope （OM）, but there are equiaxed and platelike grains. Tensile tests and Vickers hardness test indicate that yield strength, tensile strength and microhardness of the samples after forging are higher than those after rolling.

关键词： commercially pure titanium(CP-Ti) forging process rolling process microstructures mechanical properties

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基于风险管理门的高铁站场设计过程风险管理研究

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铁道标准设计 2019年第3期63卷 54-59页

作者：朱文轩徐峰柯文柱胡昊上海交通大学船舶海洋与建筑工程学院上海200240 宁安铁路有限责任公司安徽芜湖241004

高铁建设投资大、技术复杂、标准高,其站场设计过程一旦存在风险隐患将极大地影响整个高铁建设项目的进度和质量。但目前高铁站场设计过程的风险管理方法极其缺乏。对此,依托风险管理门理论,高铁站场设计过程被划分为预可行性研究、工... 详细信息

高铁建设投资大、技术复杂、标准高,其站场设计过程一旦存在风险隐患将极大地影响整个高铁建设项目的进度和质量。但目前高铁站场设计过程的风险管理方法极其缺乏。对此,依托风险管理门理论,高铁站场设计过程被划分为预可行性研究、工程可行性研究、方案优化研究、初步设计、扩大初步设计、施工图设计等6道"风险管理门",再采用阈值检查判断每道风险管理门是否达到了控制标准,从而构建了高铁站场设计过程风险管理体系,并在安九高铁建设项目中安庆西站施工图设计阶段实践应用,验证其有效性和实用性。弥补了当前高铁站场设计过程风险管理研究十分缺乏的不足,为高铁站场设计过程风险管理提供新方法,有利于提高高铁站场设计质量,控制设计过程风险,并对推动高铁设计阶段风险管理研究的发展起到积极作用。

关键词：高速铁路站场设计设计过程风险风险管理体系风险管理门阈值管理

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An efficient TILLING platform for cultivated tobacco

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Journal of Integrative Plant Biology 2020年第2期62卷 165-180页

作者： Yu-Long Gao Xue-feng Yao wen-Zheng Li Zhong-Bang Song Bing-Wu Wang Yu-Ping Wu Jun-Li Shi Guan-Shan Liu Yong-Ping Li Chun-Ming Liu key Laboratory of Tobacco Biotechnological Breeding National Tobacco Genetic Engineering Research CenterYunnan Academy of Tobacco Agricultural SciencesKunming 650021China key Laboratory of Plant Molecular Physiology Institute of Botanythe Chinese Academy of SciencesBeijing 100093China The University of Chinese Academy of Sciences Beijing 100049China Tobacco Research Institute the Chinese Agriculture Academy of SciencesQingdao 266101China Institute of Crop Sciences the Chinese Academy of Agricultural SciencesBeijing 100081China

Targeting-induced local lesions in genomes(TILLING)is a powerful reverse-genetics tool that enables high-throughput screening of genomic variations in *** TILLING has been developed for many diploid plants,the technology has been used in very few polyploid species due to their genomic ***,we established an efficient capillary electrophoresis-based TILLING platform for allotetraploid cultivated tobacco(Nicotiana tabacum L.)using an ethyl methanesulfonate(EMS)-mutagenized population of 1,536 *** optimized the procedures for endonuclease preparation,leaf tissue sampling,DNA extraction,normalization,pooling,PCR amplification,heteroduplex formation,and capillary *** a test screen using seven target genes with eight PCR fragments,we obtained 118 *** mutation density was estimated to be approximately one mutation per 106kb on *** analyses showed that mutations in two heavy metal transporter genes,HMA2S and HMA4T,led to reduced accumulation of cadmium and zinc,which was confirmed independently using CRISPR/Cas9 to generate knockout *** results demonstrate that this powerful TILLING platform(available at http://***)can be used in tobacco to facilitate functional genomics applications.

关键词： An efficient TILLING platform cultivated tobacco HMA

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