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Seasonal Variation and Land-Use/Land-Cover Type Impacts on the Correlation of Urban Heat Island Intensity and Difference Vegetation Index with Satellite Data in Xi’an,China

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Wuhan University Journal of Natural Sciences 2018年第5期23卷 387-395页

作者： ZHAO Wenting ZHU Xinming jiang guangxin GAO Zhiyuan College of Urban and Environment Northwest University

Green coverage has pronounced influences on urban heat island（UHI） effect, while the impacts of seasonal variation and Land-Use/Land-Cover（LULC） types on this effect has not been implemented. This paper investigated the spatio-seasonal characteristics of urban thermal environment and the vegetation-soil mixed area, and then explored the effects of vegetation status on UHI intensity from the perspectives of seasons and regions in Xi＇an using four Landsat 8 images. UHI intensity index was implemented to extract UHI intensity based on thermal infrared imagery, and difference vegetation index（DVI） was used to represent vegetation-soil mixed area. Results indicated that DVI has impacts on UHI intensity, and their relations vary with season and region. In the whole Xi＇an, if UHI intensity is smaller than-0.1, DVI increases with the increase of UHI intensity; whereas for UHI intensity is greater than-0.1, DVI decreases with increases of the UHI intensity from early spring to autumn. The highest correlation level was discovered in the autumn map（R^2=0.713）. Results of correlation analysis further displayed that DVI positively correlated with UHI intensity at impervious surface, and that the main urban area possessed the best correlation with R^2=0.564 5.

关键词： urban heat island （UHI） difference vegetation index（DVI） spatial and seasonal variation correlation analysis Xi＇an

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黑龙江省生态环境现状与治理对策

黑龙江农业科学 2024年第7期 74-80页

作者：王峭然宋英赫姜涛贾广新黑龙江省国土空间规划研究院黑龙江哈尔滨150090

黑龙江省生态环境条件较好,资源丰富,但仍存在水土流失、土壤退化、沙化,森林、草地、湿地和生物多样性减少、质量下降等问题。为实现人与自然和谐共生的绿色发展空间,本文简析了国内外生态环境修复的现状与趋势,按照《全国生态功能区... 详细信息

黑龙江省生态环境条件较好,资源丰富,但仍存在水土流失、土壤退化、沙化,森林、草地、湿地和生物多样性减少、质量下降等问题。为实现人与自然和谐共生的绿色发展空间,本文简析了国内外生态环境修复的现状与趋势,按照《全国生态功能区划》中生态系统空间特征,结合黑龙江省自然地理格局,探讨分析了森林、草地、湿地、水、农田和城镇6个生态系统的现状和问题。提出因地制宜开展生态系统保护、修复、治理、恢复功能等生态建设活动,科学实施生态环境保护对策,在维护生态安全底线、落实三线管控要求、平衡保护与开发、科学利用自然资源等方面提出建议。进一步落实国家政策,保障粮食安全和生态安全,努力建设自然资源可持续利用与发展的生态省。

关键词：生态环境生态保护对策生态修复生态建设

维普期刊数据库博看期刊

A literature review and integrated framework for the determinants of crowdfunding success

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Financial Innovation 2022年第1期8卷 1182-1251页

作者： Lingfei Deng Qiang Ye DaPeng Xu Wenjun Sun guangxin jiang School of Management Harbin Institute of Technology92 West Dazhi StreetHarbin 150001HeilongjiangChina

Crowdfunding is an innovative strategy for financing a new business venture from the general public instead of seeking funds in traditional ways,such as issuing bonds or bank lending.This study aims to identify the determinants affecting the success of a crowdfunding campaign and how different measurements for crowdfunding success,different crowdfunding models,and the selection of subdivided determinants influ-ence the determinants’impacts on crowdfunding success.We set the disciplines in the search strategy to select studies related to crowdfunding success.Ultimately,94 empirical papers are selected to reveal the different findings for the determinants of crowdfunding success;based on this information,we construct an integrated framework for future research.There has been much research on project-and creator-related factors;however,many of these factors have inconsistent relationships with crowdfunding success due to varying measurements of success.In particular,different measurements used within the same study for determinants or crowdfunding success may also produce inconsistent results.In addition,different crowdfunding models of a project have been found to induce additional findings.Our review of the determinants of crowdfunding success and the definitions of the determinants,as well as the proposed integrated framework,can help focus future work on relatively new or unique determinants rarely addressed in the existing literature.This work provides practical implications for both theory and practice,and directions for future research.

关键词： framework inconsistent finding

斯布牦牛线粒体D_Loop区域遗传多样性研究

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中国饲料 2024年第11期 27-32页

作者：朱勇俄广鑫信金伟陈晓英张强曹涵文姜辉陆东祥张成福省部共建青稞和牦牛种质资源与遗传改良国家重点实验室西藏拉萨850000 农业农村部青藏高原畜禽遗传育种重点实验室西藏自治区农牧科学院畜牧兽医研究所西藏拉萨850000 西南大学动物科学技术学院重庆400416

作为我国西藏重要的牦牛国家遗传资源代表性品种,斯布牦牛对藏区畜牧业经济发展具有不可替代价值。本研究旨在利用线粒体D_Loop区域遗传变异评估不同被毛颜色的斯布牦牛类群遗传多样性。结果显示:在全部152个个体内的768 bp长度的D_Loo... 详细信息

作为我国西藏重要的牦牛国家遗传资源代表性品种,斯布牦牛对藏区畜牧业经济发展具有不可替代价值。本研究旨在利用线粒体D_Loop区域遗传变异评估不同被毛颜色的斯布牦牛类群遗传多样性。结果显示:在全部152个个体内的768 bp长度的D_Loop区域中,共发现57个多态位点,构建获得51个D_Loop单倍型,单倍型多样性(Hd)分布为0.893(黑色)~0.944(棕色),全部单倍型归属于两大系统发育分支,有12个D_Loop单倍型为两群体间共享单倍型。两群体Tajima'D和Fu's D参数均为不显著(P>0.05)且群体间遗传分歧不显著(F_(ST)=0.00409,P>0.05)。总体而言,斯布牦牛群体母系遗传多样性丰富,种群近期历史上未出现群体扩张,不同被毛颜色斯布牦牛遗传背景无显著差异。该研究对进一步明确斯布牦牛种群关系及群体遗传多样性保护提供数据支撑。

关键词：斯布牦牛线粒体DNA 遗传多样性系统发育

不同被毛颜色成年斯布牦牛生长性能比较及分子育种潜力分析

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中国饲料 2024年第5期 32-38页

作者：朱勇阮鹏程俄广鑫信金伟张强陈晓英曹涵文姜辉鲜莉莉陆东祥张成福省部共建青稞和牦牛种质资源与遗传改良国家重点实验室西藏拉萨850002 农业农村部青藏高原畜禽遗传育种重点实验室西藏自治区农牧科学院畜牧兽医研究所西藏拉萨850009 西南大学动物科学技术学院重庆400716

斯布牦牛作为我国青藏高原重要牦牛资源,其种质资源特性挖掘与遗传改良提升对西藏牦牛产业提质增效具有重要意义。本研究旨在通过挖掘不同被毛颜色斯布牦牛类群成年阶段生长性能特点,明确重要经济性状相关联候选标记的优势基因型分布,... 详细信息

斯布牦牛作为我国青藏高原重要牦牛资源,其种质资源特性挖掘与遗传改良提升对西藏牦牛产业提质增效具有重要意义。本研究旨在通过挖掘不同被毛颜色斯布牦牛类群成年阶段生长性能特点,明确重要经济性状相关联候选标记的优势基因型分布,评估斯布牦牛分子育种潜力。结果显示:5~7岁龄黑色斯布牦牛的管围及体高指标均极显著(P 0.05)。然而,棕色牦牛各年段的成年体重均值略优于黑色群体。另外,5个分布于ACSL1、MyoD1及TMEM18基因的已知与牦牛生长和泌乳等经济性状相关的标记在两个斯布牦牛类群中均存在较高比例的优势基因型,特别是TMEM18_C4447T和MyoD1_C1710T位点。两个斯布牦牛群体内各位点均未显著偏离哈代温伯格平衡(P> 0.05),表明斯布牦牛群体在历史上尚未经历强烈的关于经济性状的人工选择。本研究明确了不同被毛颜色斯布牦牛成年生长特性,解析了一系列经济性状相关遗传标记在斯布牦牛种群内的育种潜力,为探索斯布牦牛适时出栏技术及提升斯布牦牛选育进程提供了理论参考。

关键词：斯布牦牛被毛颜色生长性能遗传标记优势基因型

Phenol hydrogenation to cyclohexanone over palladium nanoparticles loaded on charming activated carbon adjusted by facile heat treatment

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2600-2606页

作者： Chunhua Zhang guangxin Yang Hong jiang Yefei Liu Rizhi Chen Weihong Xing State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 210009China Changzhou Key Laboratory of Eco-Textile Technology Changzhou Vocational Institute of Textile and GarmentChangzhou 213164China

Selective phenol hydrogenation is a green approach to produce cyclohexanone.It still remains a big challenge to prepare efficient supports of the catalysts for the phenol hydrogenation via a simple and cost-effective approach.Herein,a facile approach was developed,i.e.,direct calcination of activated carbon(AC)under argon at high temperature,to improve its structure and surface properties.The modified AC materials were supported with Pd nanoparticles(NPs)to fabricate the Pd/C catalysts.The as-prepared Pd/C600 catalyst exhibits superior catalytic performance in the phenol hydrogenation,and its turnover frequency(TOF)value is 199.2 h^-1,1.31 times to that of Pd/C-raw.The Pd/C600 catalyst presents both better hydrophobicity and more structural defects,contributing to the improved dispersibility in the reaction solution(phenol-cyclohexane),the better Pd dispersion and the smaller Pd size,which result in the enhancement of the catalytic performance.Furthermore,the as-prepared Pd/C600 catalyst shows a good recyclability.

关键词： Cyclohexanone Phenol Hydrogenation Activated carbon Catalyst

基于程式化模型与梯度信息随机克里金法的风险测度估计

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系统工程理论与实践 2022年第10期42卷 2657-2676页

作者：蔡小婷云昕姜广鑫东北财经大学管理科学与工程学院大连116025 上海大学管理学院上海200444 上海大学悉尼工商学院上海200444 哈尔滨工业大学经济与管理学院哈尔滨150001

嵌套仿真是估计金融衍生产品投资组合风险测度的常用方法,但是其仿真计算量大,运算效率较低.本文提出了基于程式化模型的随机克里金法(stochastic Kriging,SK)来对投资组合损失函数进行拟合,替代大量的内层仿真,从而提高运算效率.在此... 详细信息

嵌套仿真是估计金融衍生产品投资组合风险测度的常用方法,但是其仿真计算量大,运算效率较低.本文提出了基于程式化模型的随机克里金法(stochastic Kriging,SK)来对投资组合损失函数进行拟合,替代大量的内层仿真,从而提高运算效率.在此基础上,本文进一步提出了两种方式将梯度信息引入到基于程式化模型的SK方法,即直接利用梯度信息嵌入到SK中和利用梯度信息进行插值,后者对于程式化模型的选择具有更高的灵活性.本文利用极大似然估计的渐进正态性,进一步建立了在有梯度信息条件下验证程式化模型有效性的统计假设检验方法.最后,通过基于几何布朗运动的欧式期权、亚式期权,基于正态逆高斯过程的欧式期权,以及包含多类期权的投资组合的例子,验证所提出的SK方法的有效性,结果表明带有程式化模型和梯度信息的SK方法可以提高估计的精度,提高运算效率.

关键词：蒙特卡罗方法风险度量随机克里金法嵌套仿真随机梯度估计

强γ抑制的^(6)Li F/ZnS(Ag)中子探测器研制及性能测试

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原子能科学技术 2023年第11期57卷 2218-2224页

作者：夏庆中蒋勇夏广新何铁中国工程物理研究院成都科学技术发展中心四川成都610299 四川海鹏里科技有限公司四川成都610059

在慢热中子探测领域,为应对3He气体资源的日益短缺,迫切需要研究新型中子探测器以替代3He气体探测器。基于^(6)Li F/ZnS(Ag)的闪烁体材料由于具有中子截面大、探测效率高、γ抑制强等特点,是较为理想的中子探测材料。本文采用蒙特卡罗程... 详细信息

在慢热中子探测领域,为应对3He气体资源的日益短缺,迫切需要研究新型中子探测器以替代3He气体探测器。基于^(6)Li F/ZnS(Ag)的闪烁体材料由于具有中子截面大、探测效率高、γ抑制强等特点,是较为理想的中子探测材料。本文采用蒙特卡罗程序MCNP5构建闪烁体结构模型,在不同质量比、厚度参数条件下计算了中子探测效率,并对闪烁体结构参数进行了优化设计。利用纯国产的^(6)Li F和ZnS(Ag)材料研制了不同质量比和不同厚度的^(6)Li F/ZnS(Ag)闪烁体。通过252 Cf源和60 Co源测试了不同厚度和不同质量比条件下^(6)Li F/ZnS(Ag)闪烁体的探测效率及γ灵敏度。测试结果表明,^(6)Li F和ZnS(Ag)质量比1∶3、厚度400μm是较为理想的中子探测参数。新研制的^(6)Li F/ZnS(Ag)闪烁体的热中子探测效率达到30%以上,对γ具有较强的抑制能力,在45 mV阈值设置条件下γ灵敏度可达10-7。

关键词： 3He短缺探测效率 ^(6)Li F/ZnS(Ag)闪烁体 γ灵敏度

MiR-29b suppresses the proliferation and migration of osteosarcoma cells by targeting CDK6

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Protein & Cell 2016年第6期7卷 434-444页

作者： Kegan Zhu Lei Liu Junliang Zhang Yanbo Wang Hongwei Liang Gentao Fan Zhenhuan jiang Chen-Yu Zhang Xi Chen guangxin Zhou Department of Orthopedics School of Medicine Jinling Hospital Nanjing University Nanjing 210002 China State Key Laboratory of Pharmaceutical Biotechnology.Collaborative Innovation Center ol Chemistry for Life Sciences NJU Advanced Institute for Life Sciences (NAILS) Jiangsu Engineering Research Center for MicroRNA Biology ando Biotechnology School of Life Sciences Nanjing University Nanjing 210046 China Department of Orthopedics The Affiliated Yixing Hospital of Jiangsu University Yixing 214200 China

Osteosarcoma is the most common primary sarcoma of bone, and it is a leading cause of cancer death among adolescents and young adults. However, the molecular mechanism underlying osteosarcoma carcinogenesis remains poorly understood. Recently, cyclin-dependent kinase 6 （CDK6） was identified as an important onco- gene. We found that CDK6 protein level, rather than CDK6 mRNA level, is much higher in osteosarcoma tissues than in normal adjacent tissues, which indicates a post-transcriptional mechanism involved in CDK6 regulation in osteosarcoma. MiRNAs are small non- coding RNAs that repress gene expression at the post- transcriptional level and have widely been shown to play important roles in many human cancers. In this study, we investigated the role of miR-29b as a novel regulator of CDK6 using bioinformatics methods. We demon- strated that CDK6 can be downregulated by miR-29b via binding to the 3＇-UTR region in osteosarcoma cells. Furthermore, we identified an inverse correlation between miR-29b and CDK6 protein levels in osteosar- coma tissues. Finally, we examined the function of miR- 29b-driven repression of CDK6 expression in osteosarcoma cells. The results revealed that miR-29b acts as a tumor suppressor of osteosarcoma by targeting CDK6 in the proliferation and migration processes. Taken together, our results highlight an important role for miR-29b in the regulation of CDK6 in osteosarcoma and may open new avenues for future osteosarcoma therapies.

关键词： miR-29b osteosarcoma proliferation,migration tumorigenesis