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Changes of spring wind erosion based on wind erosion climate factor in the black soil region of Northeast China

Journal of mountain Science 2023年第6期20卷 1712-1724页

作者： YAN Ping JI Sheng-tai LI Xiu-fen ZHU Hai-xia WANG Liang-liang zhai mo WANG Ping ZHAO Hui-ying Heilongjiang Institute of Meteorological Sciences Harbin 150030China Innovation and Open Laboratory of Eco-meteorology in Northeast China China Meteorological AdministrationHarbin 150030China Heilongjiang Ecological Meteorological Center Harbin 150030China

The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security of this *** this paper,based on the daily observation data of 124 meteorological stations in study area from 1961 to 2020,seasonal and monthly wind erosion climate factor(C)in spring(March to May)were calculated by using the method proposed by the Food and Agriculture Organization of the United Nations(FAO),the wind erosion characterization in spring were systematically analyzed based on C by various statistical analysis *** results showed that in the past 60 years,spring wind erosion climate factor(CSp)and monthly C of the whole region and each province(region)all showed highly significant decreasing trend,but they began to show rebounded trend in the middle or late *** of the study area showed a significant upward trend since 2008 with an increase of 4.59(10a)^(-1).The main contributors to this upward trend are the changes of C in March and in *** the four provinces(regions),CSp in Heilongjiang,Jilin,Liaoning and eastern Inner mongolia all showed rebounded since 2008,2011,2008 and 2009,*** rebounded trend of CSp in eastern Inner mongolia was the most obvious with a tendency rate of 11.27(10a)^(-1),and its mutation occurred after *** rebound trend of CSp in Heilongjiang Province takes the second place,with a trend rate of 4.72(10a)^(-1),but there’s no obvious time mutation *** spatial characteristics of CSpand monthly C are similar,showing decreasing characteristics centered on the typical black soil belt of Northeast *** with 1961-1990,in the period from 1991 to 2020,the proportion of high value areas(CSp>35,monthly C>10)has decreased to varying degrees,while the proportion of low value areas(CSp≤10,monthly C≤4)has *** trends of seasonal and monthly C in 82.2%~87.7%of the

关键词： Wind erosion climate erosivity Spatiotemporal 1characteristics Climate change Rebounded trend Typical black soil region Northeast China

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Effect of Low-temperature Imidization on Properties and Aggregation Structures of Polyimide Films with Different Rigidity

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Chinese Journal of Polymer Science 2024年第8期42卷 1134-1146页

作者： Yan Jia Lei zhai Song mo Yi Liu Li-Xin Liu Xin-Yu Du Min-Hui He Lin Fan Key Laboratory of Science and Technology on High-tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

The traditional high-temperature preparation process of polyimide can cause many problems and limits the wider application in extreme *** important challenge to be solved urgently is the reduction of imidization *** this work,twelve kinds of polyimide films with different chain rigidity were prepared at low temperature of 200℃,in the absence or presence of imidazole used as the *** molecular rigidity and free volume were theoretically calculated,and relationship between structure and properties were systematically *** results show that imidization reaction under low temperatures is significantly affected by the rigidity of molecula r *** rigid structure of polyimide is not conducive to the low-temperature imidization,but this adverse effect can be eliminated by adding catalyst,resulting the notably increased imidization *** optical and thermal properties can be improved to a certain extent for the chemically catalyzed system,resulting in relatively higher heat resistance and thermal *** the mechanical performance could be determined by com plicating factors,greatly different from polyimide films prepa red by high temperature *** investigate aggregation structures of film s,the effect of chain rigidity and catalyst on the stacking or orientation of molecular chains was further *** wo rk can contribute to the understanding of chemically catalyzed imidization that is rarely reported in the existing research,and will provide guidance for the low-temperature preparation of high-performance polyimides.

关键词： Polyimide Imidization Catalyst Structure and properties Aggregation structures

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RARRES2 regulates lipid metabolic reprogramming to mediate the development of brain metastasis in triple negative breast cancer

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Military Medical Research 2024年第1期11卷 34-49页

作者： Yi-Qun Li Fang-Zhou Sun Chun-Xiao Li Hong-Nan mo Yan-Tong Zhou Dan Lv Jing-Tong zhai Hai-Li Qian Fei Ma Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China State Key Laboratory of molecular Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Background Triple negative breast cancer(TNBC),the most aggressive subtype of breast cancer,is characterized by a high incidence of brain metastasis(BrM)and a poor *** the most lethal form of breast cancer,BrM remains a major clinical challenge due to its rising incidence and lack of effective treatment *** evidence suggested a potential role of lipid metabolic reprogramming in breast cancer brain metastasis(BCBrM),but the underlying mechanisms are far from being fully *** Through analysis of BCBrM transcriptome data from mice and patients,and immunohistochemical validation on patient tissues,we identified and verified the specific down-regulation of retinoic acid receptor responder 2(RARRES2),a multifunctional adipokine and chemokine,in BrM of *** investigated the effect of aberrant RARRES2 expression of BrM in both in vitro and in vivo *** signaling pathway components were evaluated using multi-omics *** were performed to elucidate the regulation of lipid metabolic reprogramming of *** We found that downregulation of RARRES2 is specifically associated with BCBrM,and that RARRES2 deficiency promoted BCBrM through lipid metabolic ***,reduced expression of RARRES2 in brain metastatic potential TNBC cells resulted in increased levels of glycerophospholipid and decreased levels of triacylglycerols by regulating phosphatase and tensin homologue(PTEN)-mammalian target of rapamycin(mTOR)-sterol regulatory element-binding protein 1(SREBP1)signaling pathway to facilitate the survival of breast cancer cells in the unique brain *** Our work uncovers an essential role of RARRES2 in linking lipid metabolic reprogramming and the development of ***2-dependent metabolic functions may serve as potential biomarkers or therapeutic targets for BCBrM.

关键词： RARRES2 Lipid metabolic reprogramming Brain metastasis(BrM) Breast cancer

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First identification of a novel Aichivirus D in goats with diarrhea

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Journal of Integrative Agriculture 2024年第4期23卷 1442-1446页

作者： Chen Yang Keha-mo Abi Hua Yue Falong Yang Cheng Tang College of Animal&Veterinary Sciences Southwest Minzu UniversityChengdu 610041China Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization Chengdu 610041China

Kobuvirus comprises 6 officially recognized species,namely Aichivirus A-F,and can be further divided into 20 genotypes through VP1 gene phylogenetic analysis(https://***/report/chapter/picornaviridae/picornaviridae/kobuvirus).Aichivirus A in human,Aichivirus B in bovine,Aichivirus C in porcine and caprine,Aichivirus D in yak have been proved to be associated with diarrhea(Chen Y S et al.2013;Yang et al.2015;Zhu et al.2016;zhai et al.2017;Wang et al.2020;Abi et al.2022;Yan et al.2023).

关键词： corn diarrhea official

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Application of fecal immunochemical test in colorectal cancer screening:A community-based,cross-sectional study in averagerisk individuals in Hainan

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3445-3456页

作者： Fan Zeng Da-Ya Zhang Shi-Ju Chen Run-Xiang Chen Chen Chen Shi-Mei Huang Da Li Xiao-Dong Zhang Jia-Jia Chen Cui-Yi mo Lei Gao Jun-Tao Zeng Jian-Xin Xiong zhai Chen Fei-Hu Bai Graduate School Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Department of Gastroenterology Qionghai People’s HospitalQionghai 571400Hainan ProvinceChina Department of Gastroenterology Sanya Central HospitalSanya 572022Hainan ProvinceChina Department of Gastroenterology Hainan Second People’s HospitalWuzhishang 572299Hainan ProvinceChina Department of Gastroenterology Dongfang People’s HospitalDongfang 572699Hainan ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Hainan Medical UniversityHaikou 570216Hainan ProvinceChina The Gastroenterology Clinical Medical Center of Hainan Province Haikou 570216Hainan ProvinceChina

BACKGROUND The incidence of colorectal cancer(CRC)in China is steadily rising,with a high proportion of advanced-stage *** highlights the significance of early detection and prevention measures to enhance survival *** immunochemical testing(FIT)is a globally recommended CRC screening method;however,limited research has been conducted on its application in *** To assess the efficacy and adherence of FIT screening among average-risk individuals in Hainan,while also examining the risk factors associated with positive FIT *** This population-based cross-sectional study implemented FIT screening for CRC in 2000 asymptomatic participants aged 40-75 years from five cities and 21 community health centers in Hainan *** study was conducted from August 2022 to April 2023,employing a stratified sampling method to select *** with positive FIT results subsequently underwent *** predictive values for confirmed CRC and advanced adenoma were calculated,and the relationship between relevant variables and positive FIT results was analyzed usingχ2 tests and multivariate logistic *** A total of 1788 participants completed the FIT screening,with a median age of 57 years(interquartile range:40-75).Among them,503(28.1%)were males,and 1285(71.9%)were females,resulting in an 89.4%compliance rate for FIT *** overall positivity rate of FIT was 4.4%[79 out of 1788;95%confidence interval(CI):3%-5%].The specific positivity rates for Haikou,Sanya,Orient City,Qionghai City,and Wuzhishan City were 9.6%(45 of 468;95%CI:8%-11%),1.3%(6 of 445;95%CI:0.1%-3.1%),2.7%(8 of 293;95%CI:1.2%-4.3%),3.3%(9 of 276;95%CI:1.0%-6.3%),and 4.2%(11 of 406;95%CI:1.2%-7.3%),*** associations were found between age,dietary habits,and positive FIT *** of the 79 participants with positive FIT results,55 underwent colonoscopy,demonstrating an 82.2%compliance *** them,10 had a clean

关键词： Fecal immunochemical test Colorectal cancer Adenoma Screening Hainan Province

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基于可见/近红外透射光谱的亚健康水心苹果检测

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食品与机械 2024年第7期40卷 117-125+182页

作者：王晨晨翟明灿李贺莫小明查志华吴杰石河子大学机械电气工程学院农业农村部西北农业装备重点实验室绿洲特色经济作物生产机械化教育部工程研究中心

[目的]实现亚健康水心苹果的无损检测。[方法]分别采用对数函数法和研究提出的幂函数法消除果实直径对光谱衰减的影响，并分别转换为格拉姆角差场图、格拉姆角和场图、马尔可夫变迁场图、递归图以及对称极坐标图，通过添加卷积注意力模... 详细信息

[目的]实现亚健康水心苹果的无损检测。[方法]分别采用对数函数法和研究提出的幂函数法消除果实直径对光谱衰减的影响，并分别转换为格拉姆角差场图、格拉姆角和场图、马尔可夫变迁场图、递归图以及对称极坐标图，通过添加卷积注意力模块的ResNet50网络模型挖掘与水心程度相关的图像深层特征，经t分布随机邻域嵌入方法降维并聚类分析后，将最适宜图像特征输入到改进粒子群算法优化的支持向量机、极限学习机、k近邻和随机森林分类器进行水心苹果三分类。[结果]幂函数法消除直径对透射光谱影响的效果优于对数函数法，格拉姆角差场图像特征可视化后，轮廓系数、CH分数和戴维森堡丁指数分别为0.93,0.88,0.24,均优于其余图像转换方法。ResNet50-IPSO-ELM取得了最高的分类准确率，为96.8%,测试集中对3种水心程度苹果的总体判别准确率可达96.3%,平均查准率、平均查全率和平均加权调和均值分别为87.2%,95.8%,92.3%。[结论]该模型不仅对多数类的无水心果、健康水心果保持较高分类准确率，也对少数类的亚健康水心果具有较高的判别能力。

关键词：苹果水心可见/近红外光谱光谱修正深度特征无损检测

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3 - 36 Irradiation Effects of Swift Heavy Ions on Chemical Composition of Mica Crystal

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IMP & HIRFL Annual Report 2012年第1期 126-127页

作者： Zhang Shengxia Liu Jie Zeng Jian zhai Pengfei mo Dan Sun Youmei HouMingdong

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重庆典型城区冬季碳质气溶胶的污染特征及来源解析

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环境科学 2024年第1期45卷 48-60页

作者：彭超李振亮向英王晓宸汪凌韬张晟翟崇治陈阳杨复沫翟天宇重庆市生态环境科学研究院重庆401147 中国环境科学研究院西南分院重庆401147 城市大气环境综合观测与污染防控重庆市重点实验室重庆401147 中国科学院重庆绿色智能技术研究院重庆400714 四川大学建筑与环境学院成都610065 北京大学环境科学与工程学院北京100871

于2021年1~2月在重庆典型城区万州区(WZ)、渝北区(YB)和双桥区(SQ)同步采集PM_(2.5)样品,分析冬季碳质气溶胶的污染特征、来源及潜在源区.结果表明,观测期间SQ的ρ(PM_(2.5))、ρ(OC)和ρ(EC)均值分别为(72.6±33.3)、(18.2±8.2)和(4.4... 详细信息

于2021年1~2月在重庆典型城区万州区(WZ)、渝北区(YB)和双桥区(SQ)同步采集PM_(2.5)样品,分析冬季碳质气溶胶的污染特征、来源及潜在源区.结果表明,观测期间SQ的ρ(PM_(2.5))、ρ(OC)和ρ(EC)均值分别为(72.6±33.3)、(18.2±8.2)和(4.4±1.7)μg·m^(-3),高于WZ[(67.2±30.3)、(17.2±7.4)和(5.1±2.4)μg·m^(-3)]和YB[(63.4±25.7)、(15.4±6.3)和(4.2±1.9)μg·m^(-3)].与清洁日相比,WZ污染日EC浓度及其对总碳的贡献率均涨幅最大(103.0%和8.1%),但OC/EC值下降最明显(-10.5%),表明WZ污染日碳质气溶胶的一次排放明显增强.观测期间SQ和YB的ρ(SOC)均值分别为(7.7±4.8)μg·m^(-3)和(6.9±2.8)μg·m^(-3),明显高于WZ[(4.5±1.9)μg·m^(-3)],表明二次转化对SQ和YB碳质气溶胶的影响相对较大.此外,与WZ不同,SQ和YB的SOC/OC值整体随PM_(2.5)浓度上升而增大,且SOC浓度与气溶胶液态水含量(AWC)、NO_(2)浓度和NOR值等均显著线性相关(P<0.01),表明通过液相反应生成含—NO_(2)官能团的SOC可能是SQ和YB碳质气溶胶浓度持续上升的主要因素.正定矩阵因子(PMF)解析结果表明,WZ的生物质/煤炭燃烧混合源贡献率(47.4%)明显高于YB(34.2%)和SQ(38.1%),而YB受汽油车排放和二次转化的影响较为突出.浓度权重轨迹分析(CWT)结果表明,各城区污染日碳质气溶胶主要受本地及其东北方向相邻城区(如长寿区)的影响.

关键词：碳质气溶胶污染过程二次有机碳来源解析重庆

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基于三明治阻尼结构的高速列车制动摩擦振动噪声抑制

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机械工程学报 2024年第5期60卷 196-208页

作者：项载毓莫继良贺德强朱松翟财周杜利清广西大学机械工程学院南宁530004 西南交通大学牵引动力国家重点实验室成都610031 中车戚墅堰机车车辆工艺研究所有限公司常州213011

针对高速列车制动系统在列车低运行速度、强制动盘/片摩擦作用时存在的制动尖叫噪声问题,设计了一种三明治阻尼结构以实现制动尖叫噪声的抑制以及摩擦自激振动能量的收集。在自主研制的高速列车制动性能模拟试验台上开展制动摩擦学试验... 详细信息

针对高速列车制动系统在列车低运行速度、强制动盘/片摩擦作用时存在的制动尖叫噪声问题,设计了一种三明治阻尼结构以实现制动尖叫噪声的抑制以及摩擦自激振动能量的收集。在自主研制的高速列车制动性能模拟试验台上开展制动摩擦学试验,并基于该试验装置开展摩擦块磨损及瞬态动力学分析,研究三明治阻尼结构对摩擦块表面磨损、制动界面接触及制动系统动力学行为和输出电压特性的影响。结果表明,三明治阻尼结构能够有效抑制制动摩擦振动噪声并显著影响其产生和演变,且依托自身良好的变形能力将制动摩擦振动能量转换为电能;三明治阻尼结构能够显著减小摩擦块的偏磨角度,改善摩擦块表面摩擦磨损特性和制动界面接触行为,减少制动摩擦热的产生和聚集;三明治阻尼结构良好的弹性变形能力可实现制动盘与摩擦块接触状态的实时调整,进而建立稳定的界面接触关系,使得摩擦块表面均匀磨损且整体处于滑动摩擦状态,最终实现了制动系统摩擦自激振动的有效抑制。

关键词：高速列车三明治阻尼摩擦振动噪声振动抑制能量收集

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三维多级孔炭封装硫制备在室温环境运行的锂硫电池

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新型炭材料 2021年第6期36卷 1094-1102页

作者：单宇航李丽波杜金田翟墨哈尔滨理工大学材料科学与化学工程学院黑龙江哈尔滨150040

锂硫电池由于其高能量密度和低廉的价格,将在未来的储能领域得到广泛应用。然而,它面临许多挑战,特别是在硫的负载和可溶性多硫化物的穿梭效应方面。为了解决这些问题,本文设计了一种三维多级孔炭材料(3D-HPC)作为锂硫电池中硫的载体。... 详细信息

锂硫电池由于其高能量密度和低廉的价格,将在未来的储能领域得到广泛应用。然而,它面临许多挑战,特别是在硫的负载和可溶性多硫化物的穿梭效应方面。为了解决这些问题,本文设计了一种三维多级孔炭材料(3D-HPC)作为锂硫电池中硫的载体。采用模板法,在去除模板剂聚甲基丙烯酸甲酯和氧化锌后得到了三维多孔结构。电镜和BET测试表明相互连通的大孔道与大量的大尺寸介孔协同构成了三维导电碳网络。三维网络有利于离子和电子的转移,同时通过较大尺寸的孔缓解阴极的体积膨胀,多级孔通过毛细凝结抑制了穿梭效应。电化学测试结果表明,3D-HPC-S阴极具有良好的电化学性能。在实际环境中的测试结果显示0.2倍率下3D-HPC-S首次放电比容量为1314.6 mAh·g^(−1),经100次循环后,容量保持率为69.13%。在0.5倍率下循环200次容量保持率为59.02%,平均库伦效率为98.16%。3D-HPC-S阴极有望进一步促进锂硫电池的商业化发展。

关键词：三维结构多级多孔炭大孔锂硫电池

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