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The impact of demographic dynamics on food consumption and its environmental outcomes:Evidence from China

Journal of Integrative Agriculture 2024年第2期23卷 414-429页

作者： shaoting li Xuan Chen Yanjun Ren Thomas Glauben College of Economics and Management Northwest A&F UniversityYangling 712100China Leibniz Institute of Agricultural Development in Transition Economies(IAMO) Halle(Saale)06120Germany Sino-German Center for Agricultural and Food Economics Northwest A&F UniversityYangling 712100China

With increasing population and changing demographics,food consumption has experienced a significant transition in quantity and ***,a dearth of knowledge remains regarding its environmental impacts and how it responds to demographic dynamics,particularly in emerging economies like *** the two-stage Quadratic Almost Demand System(QUAIDS)model,this study empirically examines the impact of demographic dynamics on food consumption and its environmental outcomes based on the provincial data from 2000 to 2020 in *** various scenarios,according to changes in demographics,we extend our analysis to project the long-term trend of food consumption and its environmental impacts,including greenhouse gas(GHG)emissions,water footprint(WF),and land appropriation(LA).The results reveal that an increase in the proportion of senior people significantly decreases the consumption of grain and livestock meat and increases the consumption of poultry,egg,and aquatic products,particularly for urban ***,an increase in the proportion of males in the population leads to higher consumption of poultry and aquatic ***,in the current scenario of an increased aging population and sex ratio,it is anticipated that GHG emissions,WF,and LA are likely to decrease by 1.37,2.52,and 3.56%,*** importantly,in the scenario adhering to the standards of nutritional intake according to the Dietary Guidelines for Chinese Residents in 2022,GHG emissions,WF,and LA in urban areas would increase by 12.78,20.94,and 18.32%,*** findings suggest that changing demographics should be considered when designing policies to mitigate the diet-environment-health trilemma and achieve sustainable food consumption.

关键词： demographic dynamics food consumption environmental impacts nutrition intakes

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Spatiotemporal characteristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020

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Journal of Arid Land 2024年第3期16卷 396-414页

作者： li shaoting MU Na REN Yanjun Thomas GLAUBEN College of Economics and Management Northwest A&F UniversityYangling 712100China Sino-German Center for Agricultural and Food Economics Northwest A&F UniversityYangling 712100China Leibniz Institute of Agricultural Development in Transition Economies(IAMO) Halle 06120Germany

Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally *** study used provincial-level data from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit *** addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based *** results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the *** terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative *** should be noted that these two influencing factors had different impacts on MPAs and ***,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land.

关键词： cultivated land use eco-efficiency(CLUE) slacks-based measure(SBM)model barycentre model standard deviation ellipse(SDE) panel Tobit model carbon emissions nonpoint source pollution

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2000—2020年中国城乡食物消费碳-水足迹及其驱动因素分析

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农业工程学报 2024年第5期40卷 287-296页

作者：陈萱李绍亭任彦军西北农林科技大学经济管理学院杨凌712100 中德农业与食物经济研究中心杨凌712100

随着经济发展与城镇化快速推进,中国居民膳食模式发生显著转变,并产生了严重的资源环境后果。为识别城乡居民食物消费碳-水足迹的关键驱动因素,缓解水资源消耗,助力双碳目标实现,该研究测算并对比分析了中国31(30)省市2000—2020年城乡... 详细信息

随着经济发展与城镇化快速推进,中国居民膳食模式发生显著转变,并产生了严重的资源环境后果。为识别城乡居民食物消费碳-水足迹的关键驱动因素,缓解水资源消耗,助力双碳目标实现,该研究测算并对比分析了中国31(30)省市2000—2020年城乡居民人均食物消费碳-水足迹,通过对数平均迪式指数算法(logarithmic mean index method,LMDI)对碳-水足迹进行了驱动因素分解。结果显示:2000—2020年中国城镇人均食物消费碳足迹(水足迹)增加了29.63%(32.94%),农村碳足迹(水足迹)增加了4.59%(7.91%)。从空间演变来看,城镇人均食物消费碳-水足迹较高的地区由沿海省份逐渐扩散至内陆,而农村呈南北高-中间低的分布格局。从驱动因素来看,经济水平是城乡居民食物消费碳-水足迹增加的主要动因,且消费水平表现为抑制作用;人口城镇化驱动城镇居民食物消费碳-水足迹增加,而在农村起到抑制作用。该研究从促进食物消费结构转型,多渠道拓宽食物来源等方面提出建议,旨在促进中国城乡居民食物可持续消费。

关键词：食物消费碳足迹水足迹 LMDI分解 2000—2020年中国

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Consistency of the penalized MLE for two-parameter gamma mixture models

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Science China Mathematics 2016年第12期59卷 2301-2318页

作者： CHEN JiaHua li shaoting TAN XianMing Research Institute of Big Data Yunnan University Kunming 650221 China Department of Statistics University of British Columbia Vancouver VTC 5K5 Canada Department of Biostatistics University of North Carolina at Chapel Hill Chapel Hill NC 27514 USA

Two-parameter gamma distributions are widely used in liability theory, lifetime data analysis, financial statistics, and other areas. Finite mixtures of gamma distributions are their natural extensions, and they are particularly useful when the population is suspected of heterogeneity. These distributions are successfully employed in various applications, but many researchers falsely believe that the maximum likelihood estimator of the mixing distribution is consistent. Similarly to finite mixtures of normal distributions, the likelihood function under finite gamma mixtures is unbounded. Because of this, each observed value leads to a global maximum that is irrelevant to the true distribution. We apply a seemingly negligible penalty to the likelihood according to the shape parameters in the fitted model. We show that this penalty restores the consistency of the likelihoodbased estimator of the mixing distribution under finite gamma mixture models. We present simulation results to validate the consistency conclusion, and we give an example to illustrate the key points.

关键词： constrained MLE identifiability finite mixture penalized likelihood Stirling formula

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A three-parameter logistic regression model

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Statistical Theory and Related Fields 2021年第3期5卷 265-274页

作者： Xiaoli Yu shaoting li Jiahua Chen School of Mathematics and Statistics University of British ColumbiaVancouverCanada School of Mathematics and Statistics Dongbei University of Finance and EconomicsDalianPeople’s Republic of China School of Mathematics and Statistics Yunnan UniversityKunmingPeople’s Republic of China

Dose–response experiments and data analyses are often carried out according to an optimal design under a model assumption.A two-parameter logistic model is often used because of its nice mathematical properties and plausible stochastic response *** is an extensive literature on its optimal designs and data analysis ***,a model is at best a good approximation in a real-world application,and researchers must be aware of the risk of model *** this paper,we investigate the effectiveness of the sequential EDdesign,the D-optimal design,and the up-and-down design under the three-parameter logistic regression model,and we develop a numerical method for the parameter *** show that the combination of the proposed model and the data analysis strategy performs *** the logistic model is correct,this more complex model has hardly any efficiency *** three-parameter logistic model works better than the two-parameter logistic model in the presence of model mis-specification.

关键词： effective dose level optimal design sequential ED-design up-and-down design vertex direction method

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Hexamerin and allergen are required for female reproduction in the American cockroach,Periplaneta americana

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Insect Science 2024年第1期31卷 186-200页

作者： Shiming Zhu Xiaoyi Chen Sishi Xia Qin li Ziqi Ye shaoting Zhao Kexin liu Fangfang liu Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology Institute of Insect Science and TechnologyInstitute of Insect Science and Technology&School of Life SciencesSouth China Normal UniversityGuangzhouChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouGuangdong ProvinceChina Guangdong Laboratory for lingnan Modern Agriculture South China Agricultural UniversityGuangzhouChina

Reproduction is of great importance for the continuation of the *** insects,the fat body is the major tissue for nutrient storage and involved in vitellogenesis,which is essential for female ***,2 proteins,hexamerin and allergen,were separated from the fat bodies of adult female American cockroaches(Periplaneta americana)and identified as storage proteins,encoding for 733 amino acids with molecular weight of 87.88 kDa and 686 amino acids with molecular weight of 82.18 kDa,*** encoding genes of these 2 storage proteins are mainly expressed in the fat *** interference-mediated knockdown of Hexamerin and Allergen in the early stage of the first reproductive cycle in females suppressed vitellogenesis and ovarian maturation,indicating that these storage proteins are involved in controlling ***,the expression of Hexamerin and Allergen was repressed by knockdown of the juvenile hormone(JH)receptor gene Met and the primary response gene Kr-h1,and was induced by methoprene,a JH analog,in both in vivo and in vitro ***,we have determined that hexamerin and allergen are identified as storage proteins and play an important role in promoting female reproduction in the American *** expression of their encoding genes is induced by JH *** data reveal a novel mechanism by which hexamerin and allergen are necessary for JH-stimulated female reproduction.

关键词： fat body juvenile hormone ovary reproduction storage protein vitellogenesis

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Nanoplastics promote the dissemination of antibiotic resistance genes and diversify their bacterial hosts in soil

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Eco-Environment & Health 2024年第1期3卷 1-10页

作者： lijuan liu Yuanze Sun shaoting Du Yanming li Jie Wang Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province Interdisciplinary Research Academy(IRA)Zhejiang Shuren UniversityHangzhou 310015China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

The wide application of plastics has led to the ubiquitous presence of nanoplastics and microplastics in terrestrial ***,few studies have focused on the mechanism underlying the effects of plastic particles on soil microbiomes and resistomes,especially the differences between nanoplastics and *** study investigated the microbiome and resistome in soil exposed to polystyrene microplastics(mPS)or nanoplastics(nPS)through 16S rRNA and shotgun metagenomic *** microbial communities were observed between mPS and nPS exposure groups,and nPS exposure significantly changed the bacterial composition even at the lowest amended rate(0.01%,w/w).The abundance of antibiotic resistance genes(ARGs)in nPS exposure(1%)was 0.26 copies per cell,significantly higher than that in control(0.21 copies per cell)and mPS exposure groups(0.21 copies per cell).It was observed that nanoplastics,bacterial community,and mobile genetic elements(MGEs)directly affected the ARG abundance in nPS exposure groups,while in mPS exposure groups,only MGEs directly induced the change of *** was the predominant host for multidrug in the control and mPS exposure,whereas the primary host was changed to Bacillus in nPS ***,exposure to nPS induced several bacterial hosts to exhibit possible multi-antibiotic resistance *** results indicated that the effects of plastic particles on the soil microbial community were size-dependent,and nano-sized plastic particles exhibited more substantial *** microplastics and nanoplastics promoted ARG transfer and diversified their bacterial *** findings bear implications for the regulation of plastic waste and ARGs.

关键词： Microplastics Nanoplastics Metagenomics Bacterial hosts Antibiotic resistance genes

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构建国家治理现代化的坚固基石——法治国家、法治政府、法治社会一体化建设研究

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学术前沿 2017年第16期 94-97页

作者：李少婷中国政法大学法学院

考察法治国家、法治政府、法治社会一体建设的原因、内容和关系,既是转型期的重大理论课题,也是全国各地直接面临的现实问题。在推进国家治理治理能力现代化的过程中,公权力本身的改革是关键。根据世界各地现代化转型的经验,法治作为政... 详细信息

考察法治国家、法治政府、法治社会一体建设的原因、内容和关系,既是转型期的重大理论课题,也是全国各地直接面临的现实问题。在推进国家治理治理能力现代化的过程中,公权力本身的改革是关键。根据世界各地现代化转型的经验,法治作为政治法律制度上的一种模式选择,是应对复杂性社会的基本手段。一体化建设扎根于中国改革开放实践,在核心内容基本不变的情况下,兼收并蓄古今中外人类法治建设的优秀文明成果,外延不断扩展,具有高度开放性,同时,一体化建设也是对全面推进依法治国认识上的深化和路径上的探索。

关键词：法治依法治国国家治理现代化一体化建设

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受限回程链路下无人机辅助MEC的空地能耗折中

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华中科技大学学报（自然科学版） 2024年第3期52卷 142-148页

作者：李安窦邵婷南昌大学信息工程学院江西南昌330031

针对无人机(UAV)辅助的移动边缘计算(MEC)网络中无人机的能耗和地面用户的能耗的矛盾关系,研究了受限回程链路下的UAV辅助的MEC网络的空地能耗折中问题,同时考虑到无人机的能耗与地面用户的能耗通常相差几个数量级,引入放大因子兼顾地... 详细信息

针对无人机(UAV)辅助的移动边缘计算(MEC)网络中无人机的能耗和地面用户的能耗的矛盾关系,研究了受限回程链路下的UAV辅助的MEC网络的空地能耗折中问题,同时考虑到无人机的能耗与地面用户的能耗通常相差几个数量级,引入放大因子兼顾地面用户能耗.通过联合优化计算任务分配、GUs发射功率、GUs卸载时间和无人机轨迹,以最小化加权总能耗,可以表示空地能耗之间的权衡关系.由于所提出问题的非凸性使其难以优化,提出了一种基于块坐标下降法和连续凸近似技术的两阶段交替迭代优化算法得到该问题的次优解.仿真实验结果验证了所提出的方案在兼顾公平性条件下刻画了无人机能耗和用户能耗之间的折中关系,并在降低总能耗方面优于其他基准方案.

关键词：无人机辅助的移动边缘计算受限回程链路空地能耗折中计算资源分配轨迹优化

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大气中^(210)Pb活度浓度水平与空气质量相关性研究

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环境科学与技术 2022年第3期45卷 32-37页

作者：李少婷卢奕夫刘巍湖北省核与辐射环境监测技术中心湖北武汉430070 湖北省生态环境科学研究院(省生态环境工程评估中心) 湖北武汉430072

文章用BE6530宽能型高纯锗γ能谱仪对2018-2020年采集的93组湖北武汉、黄石、襄阳、宜昌四地的气溶胶样品进行γ能谱分析。监测结果表明,四城市^(210)Pb活度浓度最大值为5.15 m Bq/m^(3),最小值为0.308 mBq/m^(3),平均值为1.668 m Bq/m^... 详细信息

文章用BE6530宽能型高纯锗γ能谱仪对2018-2020年采集的93组湖北武汉、黄石、襄阳、宜昌四地的气溶胶样品进行γ能谱分析。监测结果表明,四城市^(210)Pb活度浓度最大值为5.15 m Bq/m^(3),最小值为0.308 mBq/m^(3),平均值为1.668 m Bq/m^(3)。公众成员吸入^(210)Pb所接受的年有效剂量范围为(7.7E-07~3.0E-05)Sv,最高为10;数量级级别。^(210)Pb活度浓度与采样期间PM_(2.5)、PM_(10)、NO_(2)、AQI、SO_(2)、CO浓度显著正相关,与O;浓度显著负相关。通过多元线性回归研究发现,^(210)Pb活度浓度同时与PM_(2.5)和NO_(2)浓度这两个因素正相关。

关键词：气溶胶^(210)Pb 活度浓度相关性 PM_(2.5) NO_(2)

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