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Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons

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Biomedical and Environmental Sciences 2024年第5期37卷 479-493页

作者： LI Yang LIN Dan ZHANG Xiu Qin JU Guang Xiu SU Ya ZHANG qian DUAN Hai Ping YU Wei Sen WANG bing Ling PANG Shu Tao Department of Epidemiology and Health Statistics School of Public HealthQingdao UniversityQingdao 266021ShandongChina Department of Environmental Health Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Physicochemical Laboratory Qingdao Municipal Center for Disease Control and PreventionQingdao Institute of Preventive MedicineQingdao 266033ShandongChina Section of Child Health Care Huangdao Maternity and Child Health Care Hospital of QingdaoQingdao 266499ShandongChina Qingdao Blood Center Qingdao 266071ShandongChina

Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal *** Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old ***,37 children were categorized into low-and high-exposure groups based on the sum of the ten ***-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine ***,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina *** The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide ***,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in *** Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived *** investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes.

关键词： Child Gut microbiota Non-targeted metabolomics Polycyclic aromatic hydrocarbons Urinary metabolite profile

Controlling hydrogenation of C=C and C=O bonds in cinnamaldehyde using Pt_(1)/Ni and Pt_(1)/Co single-atom alloy catalysts

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Rare Metals 2024年第6期43卷 2859-2868页

作者： Huan-Shi Lan Yi-Da Yang Qing-Di Sun Hao Zhang Ying Zhang qian He Ran Chen Guo-Yi Bai Xiao-Hui He Hong-bing Ji School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China Key Laboratory of Bioinorganicand Synthetic Chemistry of Ministry of Education Fine Chemical Industry Research InstituteSchool of ChemistryIGCMESun Yat-sen UniversityGuangzhou510275China UBFC CNRSENSMMFEMTO-ST Institute25030 Besancon CEDEXFrance College of Chemistry and Materials Science Hebei UniversityBaoding 071002China State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology Institute of Green Petroleum Processing and Light Hydrocarbon ConversionCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China

Selective hydrogenation of C=C and C=O bonds in cinnamaldehyde(CAL)to produce desired products is a challenging task due to the complex conjugate system of the two unsaturated functional *** this study,a simple ball milling method is presented for synthesizing Pt-based single-atom alloy catalysts(SAAs)that can function as a control switch for the selective hydrogenation of CAL into highly valuable products.

关键词： alloy hydrogenation conjugate

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龚嘴水电站发电机组进水口拦污栅栅型选择

水利水电技术 2012年第11期43卷 81-83页

作者：钱冰张庆杨国电大渡河检修安装有限公司四川乐山614900

针对龚嘴水电站机组进水口拦污栅在实际使用中存在的问题,结合水电站所处地理位置、河流水文和环境实际情况,提出了对该进水口拦污栅结构进行改进的措施。据此,在不减少拦污栅过流能力的情况下,使其强度、稳定性均有较大提高。

关键词：龚嘴水电站水轮发电机组进水口拦污栅

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玉米茎基腐病原菌的分离及其生物学特性研究

河西学院学报 2024年第2期40卷 59-65页

作者：郑天翔杨娜周海瑛梁冰倩马金雷鑫王丽娟李会文雷玉明河西学院农业与生态工程学院甘肃张掖734000 甘肃省河西走廊特色资源利用重点实验室甘肃张掖734000 张掖市科技服务中心甘肃张掖734000 甘肃省植保植检站甘肃兰州730020 甘肃前进牧业科技有限责任公司甘肃张掖734000 泉州师范学院陈守仁商学院福建泉州363000 甘肃德光农业有限公司甘肃张掖734000

为探明玉米茎基腐病原菌的形态特征及生物学特性,对病原菌进行分离,并在不同温度、光照、PH值、碳源、氮源下对其进行纯培养。结果表明:该病由镰孢菌引起;菌落形态为圆形,低度突起,乳白色,少透明;菌丝为有隔菌丝,分生孢子为卵圆形或圆柱... 详细信息

为探明玉米茎基腐病原菌的形态特征及生物学特性,对病原菌进行分离,并在不同温度、光照、PH值、碳源、氮源下对其进行纯培养。结果表明:该病由镰孢菌引起;菌落形态为圆形,低度突起,乳白色,少透明;菌丝为有隔菌丝,分生孢子为卵圆形或圆柱形,有一至二个隔膜;25℃是该菌的最佳生长温度;最适宜生长的碳源和氮源分别是淀粉和蛋白胨;最适宜生长的PH值是8;且该病原菌对光照具有敏感性。该研究结果可为玉米茎基腐病的诊断及防控提供理论依据。

关键词：玉米茎基腐病镰孢菌生物学特性

反相高效液相色谱法测定丙酸发酵液中的有机酸

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分析化学 2007年第11期35卷 1651-1653页

作者：钱兵章燕李莎徐虹南京工业大学制药与生命科学学院南京工业大学制药与生命科学学院南京210009

对于生物法制备丙酸的微生物发酵体系,利用Waters Atlantis dC18反相色谱柱,以0.01mol/L KH2PO4缓冲液(pH2.8)-乙腈(95∶5,V/V)作流动相,在流速为1.0mL/min,柱温为25℃时,于紫外波长215nm处检测,9min内发酵液中的草酸、甲酸、乙酸、乳... 详细信息

对于生物法制备丙酸的微生物发酵体系,利用Waters Atlantis dC18反相色谱柱,以0.01mol/L KH2PO4缓冲液(pH2.8)-乙腈(95∶5,V/V)作流动相,在流速为1.0mL/min,柱温为25℃时,于紫外波长215nm处检测,9min内发酵液中的草酸、甲酸、乙酸、乳酸、琥珀酸和丙酸能得到良好分离。6种有机酸线性相关系数均在0.9992~1.0000之间;方法的回收率为99%~102%;RSD为0.56~1.66。本方法能够简便、快速测定丙酸发酵体系中主产物丙酸与其它有机酸含量,适于指导整个发酵过程条件的优化及发酵产物的监控。

关键词：反相高效液相色谱丙酸有机酸发酵

Spatial Distribution Pattern and Influencing Factors of Bed-and-breakfasts(B&Bs)from the Perspective of Urban-rural Differences:A Case Study of Jiaodong Peninsula,China

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Chinese Geographical Science 2024年第4期34卷 752-763页

作者： WANG Xinyue MA qian Management College Ocean University of ChinaQingdao 266100China

There are significant differences between urban and rural bed-and-breakfasts(B&Bs)in terms of customer positioning,economic strength and spatial *** identifying the differences in spatial characteristics and influencing factors of each type,is essential for creating urban and rural B&B agglomeration *** study used density-based spatial clustering of applications with noise(DBSCAN)and the multi-scale geographically weighted regression(MGWR)model to explore similarities and differences in the spatial distribution patterns and influencing factors for urban and rural B&Bs on the Jiaodong Peninsula of China from 2010 to *** results showed that:1)both urban and rural B&Bs in Jiaodong Peninsula went through three stages:a slow start from 2010 to 2015,rapid development from 2015 to 2019,and hindered development from 2019 to ***,urban B&Bs demonstrated a higher development speed and agglomeration intensity,leading to an increasingly evident trend of uneven development between the two sectors.2)The clustering scale of both urban and rural B&Bs continued to expand in terms of quantity and *** B&B clusters characterized by a limited number,but a higher likelihood of transitioning from low-level to high-level *** the number of rural B&B clusters steadily increased over time,their clustering scale was comparatively lower than that of urban B&Bs,and they lacked the presence of high-level clustering.3)In terms of development direction,urban B&B clusters exhibited a relatively stable pattern and evolved into high-level clustering centers within the main urban ***,rural B&Bs exhibited a more pronounced spatial diffusion effect,with clusters showing a trend of multi-center development along the coastline.4)Transport emerged as a common influencing factor for both urban and rural B&Bs,with the density of road network having the strongest explanatory power for their spatial *** terms of differences,populati

关键词： urban-rural bed-and-breakfasts(B&Bs) spatiotemporal evolution density-based spatial clustering of applications with noise(DBSCAN)model multi-scale geographically weighted regression(MGWR) Jiaodong Peninsula China

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论阿伦特作品中的“生物必然性”概念

云南大学学报（社会科学版） 2016年第4期15卷 81-87页

作者：杨丙乾北京大学北京100871

从人类早期的繁重劳动,到扼杀"以自由立国"之可能的贫困问题,再到消费时代里陷溺于欲望满足,阿伦特将"生物必然性"这一概念从漫长的历史演进中理出。她认为,早期人类致力于获取生存必需品而难以追求更富价值的公共生活;而现代社会虽脱... 详细信息

从人类早期的繁重劳动,到扼杀"以自由立国"之可能的贫困问题,再到消费时代里陷溺于欲望满足,阿伦特将"生物必然性"这一概念从漫长的历史演进中理出。她认为,早期人类致力于获取生存必需品而难以追求更富价值的公共生活;而现代社会虽脱离生存窘境却又沉溺于消费,这也导致人们逐渐忘记了自由的真正含义。她指出,生物必然性因其强烈的私人性而与先天要求公共性的自由之间存在巨大张力。透过对这种张力的考察,阿伦特在宏大的历史变迁中钩沉出人类的命运和理想,同时也再次表达了反极权的勇气。

关键词：生物必然性必需品消费极权主义

含有食饵自庇护的食饵-捕食模型的模糊滑模控制

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生物数学学报 2008年第4期23卷 633-638页

作者：李医民钱冰冰江苏大学理学院江苏镇江212013

针对一类含有食饵自庇护的食饵-捕食系统,当环境变化时,系统参数的扰动处于动态状态,利用其扰动边界的特性,通过设计模糊滑模控制器将失控系统引至平稳轨道,并使系统全局稳定,从理论上实现了失控系统的有效控制,为防治食饵种群灭绝,引... 详细信息

针对一类含有食饵自庇护的食饵-捕食系统,当环境变化时,系统参数的扰动处于动态状态,利用其扰动边界的特性,通过设计模糊滑模控制器将失控系统引至平稳轨道,并使系统全局稳定,从理论上实现了失控系统的有效控制,为防治食饵种群灭绝,引起食物链断裂,导致生态平衡破坏提供了一定的理论依据.最后的仿真结果表明了此方法在理论上的有效性.

关键词：食饵自庇护食饵-捕食系统模糊滑模控制器全局稳定

人力资源管理实践与小企业绩效关系的实证研究

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财贸研究 2011年第2期22卷 130-135页

作者：李前兵淮阴工学院经济管理学院江苏淮安223001

以江苏省部分小企业为例,采用结构方程建模方法,对人力资源管理实践与小企业绩效之间的关系进行实证分析,研究结果表明:人力资源管理实践水平越高,小企业的劳动生产率越高,员工自愿离职率越低;人力资源管理实践对小企业的盈利能力有积... 详细信息

以江苏省部分小企业为例,采用结构方程建模方法,对人力资源管理实践与小企业绩效之间的关系进行实证分析,研究结果表明:人力资源管理实践水平越高,小企业的劳动生产率越高,员工自愿离职率越低;人力资源管理实践对小企业的盈利能力有积极的正面作用,这种作用以生产率和员工自愿离职率为中介变量。

关键词：人力资源管理小企业绩效结构方程关系模型