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Chemical Availability of Cd, Pb and Zn in Anthropogenically Polluted Soil: Assessing the Geochemical Reactivity and Oral Bioaccessibility

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Pedosphere 2017年第3期27卷 616-629页

作者： Christophe WATERLOT Francis DOUAY aurélie PELFRENE Yncréa Hauts-de-France Laboratoire Génie Civil et géo Environnement (LGCgE)

The most recent in vitro tests used to determine metal bioaccessiblility are generally time-consuming and expensive. This study aimed at determining potential relationships between the concentrations of metals extracted using single-extraction methods and the concentrations of bioaccessible metals assessed by a harmonised in vitro test, the Unified BARGE Method （UBM）. A total number of 27 soil samples were collected from kitchen gardens and lawns with various physicochemical parameters and contamination levels. Significant relationships were obtained between Cd, Pb and Zn extracted in gastric and gastrointestinal phases and using single extractions. The best relationhips were established using acetic and citric acids for Cd, whereas for Pb, citric acid and ethylenedi- aminetetraacetic acid （EDTA） were identified as the best extractants. These relationships were improved by means of a linear multiple regression with a downward stepwise procedure involving agronomic parameters （soil cation exchange capacity and assimilated P）. This method highlighted the fact that the cation exchange capacity and P contents in soils were the two main parameters that controlled the human bioaccessibility of Cd, Pb and Zn in the gastric phase. Besides, the metal concentrations extracted with the acetic and citric acids correlated well with the metal concentrations in the gastric and gastrointestinal phases, suggesting that the bioaceessible metals were mainly in a soluble form, weakly bound to the organic matter and associated with the carbonates and the Fe and Mn oxides/hydroxides in soils.

关键词： gastric phase gastrointestinal phase linear multiple regression single extractant urban soil

The PI3K/Akt/m TOR pathway in ovarian cancer: therapeutic opportunities and challenges

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Chinese Journal of Cancer 2015年第1期34卷 4-16页

作者： Bianca Cheaib aurélie Auguste Alexandra Leary Gynecological Unit Department of MedicineGustave Roussy Comprehensive Cancer Centre Gynecological Tumor Team Translational Research Laboratory U981 Gustave Roussy Comprehensive Cancer Centre

The phosphatidylinositol 3 kinase(PI3K) pathway is frequently altered in cancer, including ovarian cancer(OC). Unfortunately, despite a sound biological rationale and encouraging activity in preclinical models, trials of first-generation inhibitors of mammalian target of rapamycin(m TOR) in OC have demonstrated negative results. The lack of patient selection as well as resistance to selective m TOR complex-1(m TORC1) inhibitors could explain the disappointing results thus far. Nonetheless, a number of novel agents are being investigated, including dual m TORC1/m TORC2, Akt, and PI3 K inhibitors. Although it is likely that inhibition of the PI3K/Akt/m TOR pathway may have little effect in unselected OC patients, certain histological types, such as clear cell or endometrioid OC with frequent phosphatidylinositol-4,5-biphosphate 3-kinase, catalytic subunit alpha(PIK3CA) and/or phosphatase and tensin homolog(PTEN) alterations, may be particularly suited to this approach. Given the complexity and redundancy of the PI3 K signaling network, PI3 K pathway inhibition may be most useful in combination with either chemotherapy or other targeted therapies, such as MEK inhibitors, anti-angiogenic therapy, and hormonal therapy, in appropriately selected OC patients. Here, we discuss the relevance of the PI3 K pathway in OC and provide an up-to-date review of clinical trials of novel PI3 K inhibitors alone or in combination with cytotoxics and novel therapies in OC. In addition, the challenges of drug resistance and predictive biomarkers are addressed.

关键词： mTOR 信号通路卵巢癌磷脂酰肌醇3激酶 AKT 激素疗法治疗临床试验

Patterns and drivers of avian taxonomic and phylogenetic beta diversity in China vary across geographical backgrounds and dispersal abilities

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Zoological Research 2024年第1期45卷 125-135页

作者： Jian-Chao Liang Zhi-Feng Ding Chun-Lin Li Yi-Ming Hu Zhi-Xin Zhou Gan-Wen lie Xiao-Nan Niu Wen-Bin Huang Hui-Jian Hu Xing-Feng Si Guangdong Key Laboratory of Animal Conservation and Resource Utilization Guangdong Public Laboratory of Wild Animal Conservation and UtilizationInstitute of ZoologyGuangdong Academy of SciencesGuangzhouGuangdong 510260China School of Resources and Environmental Engineering Anhui UniversityHefeiAnhui 230601China Guangdong Eco-Engineering Polytechnic GuangzhouGuangdong 510520China Huizhou Institute of Forestry(Huizhou Botanical Garden Management Service Center) HuizhouGuangdong 516001China Administration of National Nature Reserve for Marine Ecology of Guangdong Nanpeng Islands ShantouGuangdong 515900China Zhejiang Zhoushan Archipelago Observation and Research Station Institute of Eco-ChongmingZhejiang Tiantong Forest Ecosystem National Observation and Research StationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity ***,we examined whether the patterns and drivers of taxonomic beta diversity(TBD)and phylogenetic beta diversity(PBD)of breeding birds in China vary across(1)regions on both sides of the Hu Line,which demarcates China’s topographical,climatic,economic,and social patterns,and(2)species with different dispersal *** and PBD were calculated and partitioned into turnover and nestedness components using a moving window *** representing climate,habitat heterogeneity,and habitat quality were employed to evaluate the effects of environmental *** distance was considered to assess the impact of dispersal *** partitioning analysis was applied to assess the relative roles of these *** general,the values of TBD and PBD were high in mountainous areas and were largely determined by environmental ***,different dominant environmental filters on either side of the Hu Line led to divergent beta diversity ***,climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line,***,bird species with stronger dispersal ability were more susceptible to environmental filtering,resulting in more homogeneous *** results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns,and dispersal ability determines the response of assemblages to these ecological *** a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete ***,a comprehensive understanding of large-scale beta diversity patterns and effective pla

关键词： Beta diversity Environmental filtering Dispersal limitation Hu Line Species dispersal ability Breeding birds

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道砟嵌入路基土试样离散元虚拟三轴试验

交通运输工程学报 2024年第2期24卷 137-151页

作者：张杰聂如松李列列黄茂桐谭永长中南大学土木工程学院湖南长沙410075 中南大学重载铁路工程结构教育部重点实验室湖南长沙410075 华北水利水电大学土木与交通学院河南郑州450045

采用离散元法(DEM)从宏细观角度研究了有砟轨道道砟嵌入对路基土变形特性的影响;基于三维结构光扫描系统对道砟颗粒外形进行重构,实现道砟颗粒的精细化建模;基于DEM软件PFC3D V6.0建立高度为600 mm、直径为300 mm的道砟嵌入试样与纯土... 详细信息

采用离散元法(DEM)从宏细观角度研究了有砟轨道道砟嵌入对路基土变形特性的影响;基于三维结构光扫描系统对道砟颗粒外形进行重构,实现道砟颗粒的精细化建模;基于DEM软件PFC3D V6.0建立高度为600 mm、直径为300 mm的道砟嵌入试样与纯土试样三轴计算模型;通过有限差分法(FDM)与DEM耦合,实现三轴围压柔性加载,分别对2种试样进行三轴试验模拟;对比分析了道砟嵌入试样与纯土试样的模拟结果,明确道砟嵌入对路基土变形特性的影响。研究结果表明:围压为30 kPa时,道砟嵌入试样峰值强度为257 kPa,纯土试样峰值强度为199 kPa,相比于纯土试样,道砟嵌入会使土体承受荷载的能力降低;剪切结束时纯土试样体应变为-3.24%,道砟嵌入试样为-14.59%,道砟嵌入试样剪胀效应更为明显;纯土试样与道砟嵌入试样侧向变形机理不同,纯土试样中部产生鼓胀变形是因为其中部区域不受约束,颗粒可自由运动,道砟嵌入试样土样表层发生侧向鼓胀是因为道砟-土界面处发生的道砟嵌入对表层土颗粒向两侧挤压的排挤作用;2种试样土颗粒配位数变化趋势一致,均表现出随轴向应变先增加、后减小、最后趋于平缓的趋势,但纯土试样土颗粒配位数明显高于道砟嵌入试样;纯土试样力链沿轴向发展且分布均匀,道砟嵌入试样会在道砟-土接触界面出现明显接触力集中。

关键词：铁道工程有砟轨道离散元法模拟虚拟三轴试验道砟嵌入柔性加载

硫-氯耦合侵蚀和钙溶蚀作用下混凝土中物质传输与反应机理的数值研究

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硅酸盐学报 2024年第5期52卷 1486-1498页

作者：计洌刘清风上海交通大学船舶海洋与建筑工程学院海洋工程国家重点实验室上海200240 亚热带建筑与城市科学全国重点实验室广州510640

混凝土易受硫酸盐和氯盐的耦合侵蚀,且常伴随钙溶蚀作用,会产生严重的耐久性问题。为探明耦合侵蚀工况下混凝土的劣化机理,建立了一套基于化学反应的多离子耦合侵蚀模型,并通过第三方试验验证了模型的可靠性。本模型能够基于不同的初始... 详细信息

混凝土易受硫酸盐和氯盐的耦合侵蚀,且常伴随钙溶蚀作用,会产生严重的耐久性问题。为探明耦合侵蚀工况下混凝土的劣化机理,建立了一套基于化学反应的多离子耦合侵蚀模型,并通过第三方试验验证了模型的可靠性。本模型能够基于不同的初始材料参数和外界离子浓度预测出物质传输和产物分布情况,通过离子渗透深度、时变扩散系数和产物含量等指标研判混凝土劣化进程。同时,模型通过综合考虑钙溶蚀、硫酸盐侵蚀和氯盐侵蚀三者之间的耦合作用揭示了复杂环境因素对混凝土劣化过程的影响。研究发现短期内硫-氯间的耦合作用会抑制2种盐类的侵蚀,而忽略钙溶蚀作用会导致混凝土内部生成的钙矾石量减少但分布更广。基于该模型进一步探讨了环境/材料变量对硫-氯耦合侵蚀的影响,为预防硫-氯耦合侵蚀下混凝土耐久性问题提供理论参考。

关键词：氯离子硫酸盐钙溶蚀耦合侵蚀数值模型

Evolutionary fingerprint, phylogenetic and forest structure of tropical montane Atlantic cloud forests along an elevation gradient

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Journal of Mountain Science 2024年第4期21卷 1259-1271页

作者： Ravi Fernandes MARIANO Vanessa Leite REZENDE Cléber Rodrigo de SOUZA Patrícia Vieira POMPEU Rubens Manoel dos SANTOS Carolina Njaime MENDES Aloysio Souza de MOURA Felipe Santana MACHADO Warley Augusto Caldas CARVALHO Marco aurélio Leite FONTES Department of Forest Sciences Federal University of LavrasLavras 37200-900Brazil 2Environmental Defence Association of Minas Gerais Belo Horizonte 30360-110Brazil Department of Ecology and Conservation Federal University of LavrasLavras 37200-900Brazil Department of Forest Sciences State University of Mato Grosso do SulAquidauana 79200-000Brazil Agência Zetta Federal University of LavrasLavras 37200-900Brazil. Department of Natural Sciences Federal University of São João del-ReiSão João del-Rei 36307-352Brazil.

Environmental conditions can change markedly over geographical distances along elevation gradients,making them natural laboratories to study the processes that structure *** work aimed to assess the influences of elevation on Tropical Montane Cloud Forest plant communities in the Brazilian Atlantic Forest,a historically neglected *** evaluated the phylogenetic structure,forest structure(tree basal area and tree density)and species richness along an elevation gradient,as well as the evolutionary fingerprints of elevation-success on phylogenetic lineages from the tree *** do so,we assessed nine communities along an elevation gradient from 1210 to 2310 m *** large elevation *** relationships between elevation and phylogenetic structure,forest structure and species richness were investigated through Linear *** occurrence of evolutionary fingerprint on phylogenetic lineages was investigated by quantifying the extent of phylogenetic signal of elevation-success using a genus-level molecular *** results showed decreased species richness at higher elevations and independence between forest structure,phylogenetic structure and *** also verified that there is a phylogenetic signal associated with elevation-success by *** concluded that the elevation is associated with species richness and the occurrence of phylogenetic lineages in the tree communities evaluated in Mantiqueira *** the other hand,elevation is not associated with forest structure or phylogenetic ***,closely related taxa tend to have their higher ecological success in similar ***,we highlight the fragility of the tropical montane cloud forests in the Mantiqueira Range in face of environmental changes(*** warming)due to the occurrence of exclusive phylogenetic lineages evolutionarily adapted to environmental conditions(*** temperature)associated with each elevation range.

关键词： Atlantic Forest Cloud forest Conservation Community ecology Montane forests Phylogenetic diversity Phylogenetic signal

国际视阈下的博物馆交互设计研究现状、热点与趋势——基于CiteSpace可视化计量分析

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南京艺术学院学报（美术与设计） 2024年第4期 90-96页

作者：王泓凯张烈清华大学美术学院北京100084

本研究利用CiteSpace可视化计量分析软件,梳理了WOS数据库中的国际博物馆交互设计研究相关文献,并对其发文量趋势、核心作者、核心国家、核心机构、出版物双图叠加、文献共被引、关键词聚类等进行了可视化分析。通过这些分析,可以深入... 详细信息

本研究利用CiteSpace可视化计量分析软件,梳理了WOS数据库中的国际博物馆交互设计研究相关文献,并对其发文量趋势、核心作者、核心国家、核心机构、出版物双图叠加、文献共被引、关键词聚类等进行了可视化分析。通过这些分析,可以深入了解国外博物馆交互设计的研究现状、热点和趋势,分析结果可以为我国该领域的研究提供参考和借鉴。

关键词：博物馆交互设计 WOS CiteSpace 知识图谱

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审计师关心年报前瞻性文本信息吗?

审计研究 2024年第1期 65-75页

作者：何璐伶沈烈广西民族大学国际教育学院 530006 中南财经政法大学会计学院 430073

此前研究主要关注历史信息与审计师决策,本文考察年报前瞻性文本信息对审计定价的影响。研究发现,年报前瞻性文本信息与审计定价显著负相关。机制检验发现,年报前瞻性文本信息能传递企业未来持续经营信号,降低审计师所感知的持续经营风... 详细信息

此前研究主要关注历史信息与审计师决策,本文考察年报前瞻性文本信息对审计定价的影响。研究发现,年报前瞻性文本信息与审计定价显著负相关。机制检验发现,年报前瞻性文本信息能传递企业未来持续经营信号,降低审计师所感知的持续经营风险,进而降低审计定价。异质性检验发现,当年报披露语调更积极、披露未来经营计划内容更丰富时,二者负向关系更显著;且这种负向关系仅在企业未来盈余反应系数更高和分析师关注更多以及审计师行业专长较低和忙碌程度更高的样本中才显著。进一步研究发现,年报前瞻性文本信息披露能够显著降低企业被出具持续经营不确定性审计意见的概率。本文为理解审计师决策依据提供了新的理论参考,并为现有审计定价影响因素的研究作出增量贡献。

关键词：前瞻性文本信息审计定价持续经营审计意见

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市场结构、地方保护与异常审计费用

中国软科学 2024年第6期 202-213页

作者：沈烈王浩然中南财经政法大学会计学院湖北武汉430073

构建公平有序的市场体系需要厘清市场垄断和地方保护对审计契约的影响。以沪深两市2015-2022年的上市公司为研究样本,实证检验市场结构集中度对异常审计费用的影响,进一步考察地方保护对审计契约的调节效应。研究发现:(1)市场结构集中... 详细信息

构建公平有序的市场体系需要厘清市场垄断和地方保护对审计契约的影响。以沪深两市2015-2022年的上市公司为研究样本,实证检验市场结构集中度对异常审计费用的影响,进一步考察地方保护对审计契约的调节效应。研究发现:(1)市场结构集中度对异常审计费用具有显著负向影响,而地方保护进一步增强负向关系;(2)在异常审计费用为负时市场结构集中度和地方保护对异常审计费用的影响更显著,而年报问询函外部监督效用受地方保护制约;(3)市场结构集中度通过代理成本和审计时长影响异常审计费用,进而损害会计信息的稳健性和可比性。

关键词：市场结构地方保护异常审计费用