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Mapping soil organic matter in cultivated land based on multi-year composite images on monthly time scales

Journal of Integrative Agriculture 2024年第4期23卷 1393-1408页

作者： Jie Song dongsheng yu Siwei Wang Yanhe Zhao Xin Wang Lixia Ma Jiangang Li State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Agricultural and Rural Bureau of Luanping County Luanping 068250China Chinese Academy of Sciences University Beijing 100049China

Rapid and accurate acquisition of soil organic matter(SOM)information in cultivated land is important for sustainable agricultural development and carbon balance *** study proposed a novel approach to predict SOM with high accuracy using multiyear synthetic remote sensing variables on a monthly *** obtained 12 monthly synthetic Sentinel-2 images covering the study area from 2016 to 2021 through the Google Earth Engine(GEE)platform,and reflectance bands and vegetation indices were extracted from these composite *** the random forest(RF),support vector machine(SVM)and gradient boosting regression tree(GBRT)models were tested to investigate the difference in SOM prediction accuracy under different combinations of monthly synthetic *** showed that firstly,all monthly synthetic spectral bands of Sentinel-2 showed a significant correlation with SOM(P<0.05)for the months of January,March,April,October,and ***,in terms of single-monthly composite variables,the prediction accuracy was relatively poor,with the highest R^(2)value of 0.36 being observed in *** monthly synthetic environmental variables were grouped in accordance with the four quarters of the year,the first quarter and the fourth quarter showed good performance,and any combination of three quarters was similar in estimation *** overall best performance was observed when all monthly synthetic variables were incorporated into the ***,among the three models compared,the RF model was consistently more accurate than the SVM and GBRT models,achieving an R^(2)value of *** for band 12 in December,the importance of the remaining bands did not exhibit significant *** research offers a new attempt to map SOM with high accuracy and fine spatial resolution based on monthly synthetic Sentinel-2 images.

关键词： soil organic matter Sentinel-2 monthly synthetic images machine learning model spatial prediction

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Incorporation of source contributions to improve the accuracy of soil heavy metal mapping using small sample sizes at a county scale

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Pedosphere 2024年第1期34卷 170-180页

作者： Jie SONG Xin WANG dongsheng yu Jiangang LI Yanhe ZHAO Siwei WANG Lixia MA State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Chinese Academy of Sciences University Beijing 100049China Agricultural and Rural Bureau of Luanping County Luanping 068250China

Estimating heavy metal(HM) distribution with high precision is the key to effectively preventing Chinese medicinal plants from being polluted by the native soil. A total of 44 surface soil samples were gathered to detect the concentrations of eight HMs(As, Hg, Cu, Cr, Ni, Zn, Pb, and Cd) in the herb growing area of Luanping County, northeastern Hebei Province, China. An absolute principal component score-multiple linear regression(APCS-MLR) model was used to quantify pollution source contributions to soil HMs. Furthermore, the source contribution rates and environmental data of each sampling point were simultaneously incorporated into a stepwise linear regression model to identify the crucial indicators for predicting soil HM spatial distributions. Results showed that 88% of Cu, 72% of Cr, and 72% of Ni came from natural sources;50% of Zn, 49% of Pb, and 59% of Cd were mainly caused by agricultural activities;and 44% of As and 56% of Hg originated from industrial activities. When three-type(natural, agricultural, and industrial) source contribution rates and environmental data were simultaneously incorporated into the stepwise linear regression model, the fitting accuracy was significantly improved and the model could explain 31%–86% of the total variance in soil HM concentrations. This study introduced three-type source contributions of each sampling point based on APCS-MLR analysis as new covariates to improve soil HM estimation precision, thus providing a new approach for predicting the spatial distribution of HMs using small sample sizes at the county scale.

关键词： absolute principal component score-multiple linear regression Chinese herbal medicine influencing factors spatial distribution stepwise multiple regression

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Rhizosphere microbes influence wogonoside accumulation in perennial Scutellaria baicalensis

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Pedosphere 2024年第3期34卷 553-566页

作者： Yang SUN Hong LIU Junwei PENG Minchong SHEN Yang HU dongsheng yu Jiangang LI yuanhua DONG CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Tobacco Research Institute of Chinese Academy of Agricultural Sciences Qingdao 266101(China)

Dried roots of Scutellaria baicalensis Georgi are an acclaimed traditional Chinese medicine,and wogonoside content is a key indicator used to evaluate *** *** than rising linearly with cultivation years,*** quality initially increases and then ***,little is known regarding the dynamic variations in *** rhizosphere microorganisms under long-term cultivation and underlying mechanisms of their effects on wogonoside formation and *** aim of this study was to investigate the roles of soil nutrients and rhizosphere microbes on *** quality across different cultivation years(1-4 years).The wogonoside content(25.14 mg g^(-1))was highest in the biennial *** and then decreased following long-term *** soil nutrients(available nitrogen,available phosphorus,available iron,available manganese,and available zinc)were reduced significantly as cultivation years *** also affected rhizosphere bacterial community structure significantly,driving it toward deterministic process(i.e.,β-nearest taxon index<-2).Available manganese and exchangeable calcium indirectly affected wogonoside formation and *** inhibition was driven by the reduction in rhizosphere bacterial diversity,which significantly increased the relative abundance of beta-glucosidase and decreased the relative abundance of phenylalanine *** rhizosphere microenvironment was altered under long-term cultivation,thereby shaping rhizosphere bacterial community,reducing the community diversity,and ultimately inhibiting wogonoside formation and *** findings may aid in understanding of the mechanisms and reasons for the reduction in *** quality under long-term cultivation from the perspective of soil nutrients and microorganisms,which may theoretically support the future artificial cultivation and management of Chinese medicinal plants.

关键词： bacterial diversity medicinal plant rhizosphere bacterial community soil nutrient wogonoside content wogonoside formation

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Cdc42 deletion yielded enamel defects by disrupting mitochondria and producing reactive oxygen species in dental epithelium

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Genes & Diseases 2024年第5期11卷 335-349页

作者： Jinxuan Zheng Rongcheng yu Yiqi Tang Sihui Su Sainan Wang Chenxi Liao Xuecong Li Jiabin Liao dongsheng yu Tingting Ai Wei Zhao Vicky Yau Chufeng Liu Liping Wu Yang Cao Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong 510055China Guangdong Provincial Key Laboratory of Oral Diseases GuangzhouGuangdong 510055China Department of Cariology and Endodontology Peking University School and Hospital of Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijing 100081China Department of Oral and Maxillofacial Surgery University at BuffaloBuffaloNY 14214USA Department of Orthodontics Stomatological HospitalSouthern Medical UniversityGuangzhouGuangdong 510280China

Developmental defects of enamel are common due to genetic and environmental factors before and after ***42,a Rho family small GTPase,regulates prenatal tooth development in ***,its role in postnatal tooth development,especially enamel formation,remains ***,we investigated Cdc42 functions in mouse enamel development and tooth repair after ***42 showed highly dynamic temporospatial patterns in the developing incisors,with robust expression in ameloblast and odontoblast ***,epithelium-specific Cdc42 deletion resulted in enamel defects in *** differentiation was inhibited,and hypomineralization of enamel was observed upon epithelial Cdc42 *** analysis showed that abnormal mitochondrial components,phosphotransferase activity,and ion channel regulator activity occurred in the Cdc42 mutant dental *** oxygen species accumulation was detected in the mutant mice,suggesting that abnormal oxidative stress occurred after Cdc42 ***,Cdc42 mutant mice showed delayed tooth repair and generated less calcified *** dysfunction and abnormal oxygen consumption were evidenced by reduced Apool and Timm8a1 expression,increased Atp5j2 levels,and reactive oxygen species overproduction in the mutant repair ***-specific Cdc42 deletion attenuated ERK1/2 signaling in the labial cervical *** Sox2 expression in the mutant labial cervical loop after clipping might lead to delayed tooth *** findings suggested that mitochondrial dysfunction,up-regulated oxidative stress,and abnormal ion channel activity may be among multiple factors responsible for the observed enamel defects in Cdc42 mutant ***,Cdc42 exerts multidimensional and pivotal roles in enamel development and is particularly required for ameloblast differentiation and enamel matrix formation.

关键词： Cdc42 Enamel defects Mitochondrial dysfunction Rho GTPase Tooth repair

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三相CLLC谐振变换器磁集成平面变压器设计与优化

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电工技术学报 2024年第12期39卷 3774-3786页

作者：程鹤徐恺李朋圣齐乃菊于东升中国矿业大学电气工程学院徐州221116

三相CLLC谐振变换器凭借其高效率、大容量、低器件应力等优势而受到广泛关注。然而,多相结构的磁性元件数量多、体积大,是制约功率变换器尺寸的主要因素。随着宽禁带(WBG)半导体器件的出现,功率变换器的开关频率显著提高,这也为印制电路... 详细信息

三相CLLC谐振变换器凭借其高效率、大容量、低器件应力等优势而受到广泛关注。然而,多相结构的磁性元件数量多、体积大,是制约功率变换器尺寸的主要因素。随着宽禁带(WBG)半导体器件的出现,功率变换器的开关频率显著提高,这也为印制电路板(PCB)绕组的使用提供了有利条件。与传统绕线式绕组相比,PCB绕组的扁平特性更适用于平面磁性元件。此外,由于高频带来的低电感需求也使得基于PCB绕组的平面磁性元件更有利于实现集成。该文提出一种新型的基于PCB绕组的电感和变压器的集成结构,详细分析磁心结构的磁路模型,并给出集成磁件的优化设计方法,最后通过搭建一台基于SiC器件的800 V/10 kW的实验样机进行验证。实验结果表明,该集成方案可有效减小变换器的体积和损耗,具有高功率密度和高效率。

关键词：三相CLLC谐振变换器 PCB绕组磁集成优化设计

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公共部门人才集聚会影响企业创新绩效吗

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财贸经济 2024年第7期45卷 112-129页

作者：李小平田璞余东升中南财经政法大学科学研究部 430073 中南财经政法大学社会科学研究院 430073 中南财经政法大学经济学院 430073 中南财经政法大学统计与数学学院 430073

公共部门人才集聚关系到人才资源在公共部门和私营部门间的配置效率,合理分配人才资源是实施创新驱动发展战略的重要保障。本文利用全国各省、市、县、乡公务员招录数据,考察了公共部门人才集聚对企业创新绩效的影响。研究发现,公共部... 详细信息

公共部门人才集聚关系到人才资源在公共部门和私营部门间的配置效率,合理分配人才资源是实施创新驱动发展战略的重要保障。本文利用全国各省、市、县、乡公务员招录数据,考察了公共部门人才集聚对企业创新绩效的影响。研究发现,公共部门人力资本扩张能够显著改善企业创新绩效。具体而言,公共部门扩大“本硕博”高学历人才招录规模可以显著促进企业研发创新水平提升,而扩大专科及以下学历人员招录规模对企业研发创新无显著影响。作用机制检验证实,公共部门人才集聚通过优化营商环境、提高政府科研投入水平、提升企业研发创新效率等渠道来改善企业创新绩效。异质性分析表明,公共部门人才集聚对高新技术企业、国有企业和私营企业研发创新能力具有显著的促进作用,特超大型城市公共部门吸纳人才资源能够显著改善企业创新绩效。进一步研究发现,公共部门人才集聚可以显著提高企业创新质量,优化创新专利结构。本文从公共部门人事招聘视角,对公共部门人才集聚是否不利于私营部门研发创新予以正面回应,为政府优化人才资源在部门间的配置提供了有益参考。

关键词：公共部门人才资源分配私营部门创新绩效

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装配式建筑项目风险识别:基于文献计量与文本分析

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科技和产业 2024年第10期24卷 26-32页

作者：于冬升黄源华贺州学院建筑与电气工程学院广西贺州542899

以中国知网收录的80篇装配式建筑风险研究领域的文献为研究对象,基于文献计量和文本分析研究装配式建筑项目风险识别方法、风险分类及常见风险。研究结果表明,文献综述是最常用的风险识别方法;环境、资源、施工、管理、供应链为装配式... 详细信息

以中国知网收录的80篇装配式建筑风险研究领域的文献为研究对象,基于文献计量和文本分析研究装配式建筑项目风险识别方法、风险分类及常见风险。研究结果表明,文献综述是最常用的风险识别方法;环境、资源、施工、管理、供应链为装配式建筑项目常见风险类别;自然灾害、恶劣气候及不可抗力,作业人员风险意识淡薄,装配式构件质量问题,设计方案可行性与集成性差,施工现场吊装作业环境及周边环境不利为装配式建筑项目常见风险因素。针对常见风险因素,提出了对策建议,以期为装配式建筑项目风险管理提供借鉴。

关键词：装配式建筑风险识别文献计量

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超声诊断胎儿孤立性巨指畸形1例

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医学影像学杂志 2024年第5期34卷 175-176页

作者：王玲于东升青岛大学附属山东省妇幼保健院超声科山东济南250014 山东省潍坊市寒亭区高里街道中心卫生院放射科山东潍坊261102

孕妇29岁。妊娠26周,G2P1。主诉及家族史无异常,体格检查未见明显异常。超声检查胎儿各项生长参数(双顶径、头围、腹围和股骨长度)正常,但发现胎儿右手明显大于左手,显示右手掌骨明显大于左手掌骨(表1,2),尤其拇指与食指肥大,且食指长径... 详细信息

孕妇29岁。妊娠26周,G2P1。主诉及家族史无异常,体格检查未见明显异常。超声检查胎儿各项生长参数(双顶径、头围、腹围和股骨长度)正常,但发现胎儿右手明显大于左手,显示右手掌骨明显大于左手掌骨(表1,2),尤其拇指与食指肥大,且食指长径为28.1 mm,横径为9.0 mm,左手食指相应长径为20.3 mm、横径为5.3 mm。

关键词：先天性巨指畸形超声检查

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建设项目土地征收社会稳定风险识别与评估

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科技和产业 2024年第14期24卷 181-185页

作者：黄源华于冬升贺州学院建筑与电气工程学院广西贺州542899

基于文献研究与专家访谈识别建设项目土地征收社会稳定风险因素22项,将社会稳定风险因素按合法性、合理性、可行性、可控性进行分类,构建了建设项目土地征收社会风险因素清单。采用评估实例对风险因素清单加以验证,评估结果显示,拟征地... 详细信息

基于文献研究与专家访谈识别建设项目土地征收社会稳定风险因素22项,将社会稳定风险因素按合法性、合理性、可行性、可控性进行分类,构建了建设项目土地征收社会风险因素清单。采用评估实例对风险因素清单加以验证,评估结果显示,拟征地项目的组合风险指数为0.24,属于低社会稳定风险。

关键词：建设项目土地征收社会稳定风险识别

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杵棒点穴联合温针灸对寒湿型腰椎间盘突出症患者炎症反应及腰痛程度的影响

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反射疗法与康复医学 2024年第2期5卷 16-18页

作者：于东升柳双双烟台市市直机关医院康复科山东烟台264001

目的探讨杵棒点穴联合温针灸对寒湿型腰椎间盘突出症(LDH)患者炎症反应及腰痛程度的影响.方法选取2021年5月—2023年9月该院收治的88例寒湿型LDH患者为研究对象,按照随机数字表法将其分为观察组(n=44)和对照组(n=44).对照组患者给予温... 详细信息

目的探讨杵棒点穴联合温针灸对寒湿型腰椎间盘突出症(LDH)患者炎症反应及腰痛程度的影响.方法选取2021年5月—2023年9月该院收治的88例寒湿型LDH患者为研究对象,按照随机数字表法将其分为观察组(n=44)和对照组(n=44).对照组患者给予温针灸治疗,观察组患者于温针灸基础上加用杵棒点穴治疗.比较两组临床疗效、腰痛程度、腰椎功能、炎症反应、不良反应发生情况.结果观察组临床总有效率为95.45%,高于对照组的79.55%,差异有统计学意义(P0.05).结论在寒湿型LDH患者中实施杵棒点穴联合温针灸效果显著,可缓解腰痛程度,减轻炎症反应,促进其腰椎功能改善,且安全性高.

关键词：腰椎间盘突出症寒湿型温针灸杵棒点穴炎症反应

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