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时间角逐、符号消费与情感异化:青年群体“特种兵式旅游”现象的本质及成因探析

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山西青年职业学院学报 2024年第2期37卷 8-12,17页

作者：杨广筱肖帅河南大学新闻与传播学院河南开封475000

“特种兵式旅游”是以青年为主要参与群体的旅游打卡热潮,是流动于青年群体间的隐形社交货币和媒介化旅行的变身。以青年为受访者,采用半结构化访谈法,通过询问受访者加入“特种兵式旅游”的过程及旅游后的感受,考察青年加入旅游打卡热... 详细信息

“特种兵式旅游”是以青年为主要参与群体的旅游打卡热潮,是流动于青年群体间的隐形社交货币和媒介化旅行的变身。以青年为受访者,采用半结构化访谈法,通过询问受访者加入“特种兵式旅游”的过程及旅游后的感受,考察青年加入旅游打卡热潮的原因。研究发现,“特种兵式旅游”本质上是一种青年亚文化现象,是青年群体陷入时间焦虑、情感异化和消费景观后寻求短暂脱嵌的方式之一,映射出其在社会转型时期不稳定的社会心态。

关键词：特种兵式旅游青年旅游情感异化符号消费

冻融循环作用下结构面剪切力学性质劣化规律研究

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价值工程 2024年第16期43卷 130-132页

作者：杨晓光王骞中国黄金集团内蒙古矿业有限公司满洲里021400

岩石结构面的季节性冻融是影响岩石稳定性的主要因素之一。本文以寒区岩体工程为背景,开展了不同冻融循环次数(0~5次)、不同剪切角度(45°、60°)下的结构面冻融循环剪切试验,研究了冻融循环下结构面的力学性质。研究结果表明:随着冻融... 详细信息

岩石结构面的季节性冻融是影响岩石稳定性的主要因素之一。本文以寒区岩体工程为背景,开展了不同冻融循环次数(0~5次)、不同剪切角度(45°、60°)下的结构面冻融循环剪切试验,研究了冻融循环下结构面的力学性质。研究结果表明:随着冻融次数的不断增加,结构面的剪切强度、剪切模量、粘聚力和内摩擦角不断降低,剪应变不断增大,剪切强度的下降主要是由于粘聚力下降引起的,剪切角度较高的结构面塑性变形特征更加明显。研究成果可为寒区岩体边坡稳定性分析提供理论与试验支持。

关键词：结构面冻融循环力学参数剪切试验

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The Possible Effect of Climate Warming on Northern Limits of Cropping System and Crop Yield in China

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Agricultural Sciences in China 2011年第4期10卷 585-594页

作者： yang xiao-guang LIU Zhi-juan CHEN Fu College of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R. China College of Agronomy and Biotechnology China Agricultural University Beijing 100193 P.R.China

Significantly increasing temperature since the 1980s in China has become a consensus under the background of global climate change and how climate change affects agriculture or even cropping systems has attracted more and more attention from Chinese government and scientists. In this study, the possible effects of climate warming on the national northern limits of cropping systems, the northern limits of winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation in China from 1981 to 2007 were analyzed. Also, the possible change of crop yield caused by planting limits displacement during the periods 1950s-1981 and 1981-2007 was compared and discussed. The recognized calculation methods of agricultural climatic indices were employed. According to the indices of climatic regionalization for cropping systems, the national northern limits of cropping systems, winter wheat and double rice, and the stable-yield northern limits of rainfed winter wheat-summer maize rotation during two periods, including the 1950s-1980 and 1981-2007, were drawn with ArcGIS software. Compared with the situation during the 1950s- 1980, the northern limits of double cropping system during 1981-2007 showed significant spatial displacement in Shaanxi, Shanxi, Hebei, and Liaoning provinces and Beijing municipality, China. The northern limits of triple cropping system showed the maximum spatial displacement in Hunan, Hubei, Anhui, Jiangsu, and Zhejiang provinces, China. Without considering variety change and social economic factors, the per unit area grain yield of main planting patterns would increase about 54-106% if single cropping system was replaced by double cropping system, which turned out to be 27- 58% if double cropping system was replaced by triple cropping system. In Liaoning, Hebei, Shanxi, Shaanxi, Gansu, and Qinghai provinces, Inner Mongolia and Ningxia autonomous regions, China, the northern limits of winter wheat during 1981-200

关键词： climate warming the northern limits of cropping system the planting northern limits of winter wheat the planting northern limits of double rice crop yield

Geographic Variation of Rice Yield Response to Past Climate Change in China

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Journal of Integrative Agriculture 2014年第7期13卷 1586-1598页

作者： yang Jie XIONG Wei yang xiao-guang CAO yang FENG Ling-zhi College of Resources and Environmental Sciences China Agricultural University Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences International Institute for Applied Systems Analysis (IIASA) Ecosystems Services and Management Program Laxenburg 2361 Austria Department of Agricultural and Biological Engineering University of Florida Gainesville FL 32600-0570 USA

Previous studies demonstrated climate change had reduced rice yield in China, but the magnitude of the reduction and the spatial variations of the impact have remained in controversy to date. Based on a gridded daily weather dataset, we found there were obvious changes in temperatures, diurnal temperature range, and radiation during the rice-growing season from 1961 to 2010 in China. These changes resulted in a signiifcant decline of simulated national rice yield （simulated with CERES-Rice）, with a magnitude of 11.5%. However, changes in growing-season radiation and diurnal temperature range, not growing-season temperatures, contributed most to the simulated yield reduction, which conifrmed previous estimates by empirical studies. Yield responses to changes of the climatic variables varied across different rice production areas. In rice production areas with the mean growing-season temperature at 12-14＆#176;C and above 20＆#176;C, a 1＆#176;C growing-season warming decreased rice yield by roughly 4%. This decrease was partly attributed to increased heat stresses and shorter growth period under the warmer climate. In some rice areas of the southern China and the yangtze River Basin where the rice growing-season temperature was greater than 20＆#176;C, decrease in the growing-season radiation partly interpreted the widespread yield decline of the simulation, suggesting the signiifcant negative contribution of recent global dimming on rice production in China＇s main rice areas. Whereas in the northern rice production areas with relatively low growing-season temperature, decrease of the diurnal temperature range was identiifed as the main climatic contributor for the decline of simulated rice yield, with larger decreasing magnitude under cooler areas.

关键词： climate change yield responses rice China

Protein Requirements in Healthy Adults: A Meta-analysis of Nitrogen Balance Studies

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Biomedical and Environmental Sciences 2014年第8期27卷 606-613页

作者： LI Min SUN Feng PIAO Jian Hua yang xiao guang Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention School of public health Peking university

Objective The goal of this study was to analyze protein requirements in healthy adults through a meta-analysis of nitrogen balance studies. Methods A comprehensive search for nitrogen balance studies of healthy adults published up to October 2012 was performed, each study were reviewed, and data were abstracted. The studies were first evaluated for heterogeneity. The average protein requirements were analyzed by using the individual data of each included studies. Study site climate, age, sex, and dietary protein source were compared. Results Data for 348 subjects were gathered from 28 nitrogen balance studies. The natural logarithm of requirement for 348 individuals had a normal distribution with a mean of 4.66. The estimated average requirement was the exponentiation of the mean of the log requirement, 105.64 mg N/kg·d. No significant differences between adult age, source of dietary protein were observed. But there was significant difference between sex and the climate of the study site （P〈0.05）. Conclusion The estimated average requirement and recommended nutrient intake of the healthy adult population was 105.64 mg N/kg·d （0.66 g high quality protein/kg·d） and 132.05 mg N/kg·d （0.83 g high quality protein/kg·d）, respectively.

关键词： Protein requirement Nitrogen balance Estimated average requirement Recommendednutrient intake

Current status and trends of wheat genetic transformation studies in China

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Journal of Integrative Agriculture 2015年第3期14卷 438-452页

作者： HE Yi WANG Qiong ZENG Jian SUN Tao yang guang-xiao HE guang-yuan The Genetic Engineering International Cooperation Base Ministry of Science and Technology/Key Laboratory of Molecular Biophysics Ministry of Education/College of Life Science and Technology Huazhong University of Science & Technology

More than 20 years have passed since the first report on successful genetic transformation of wheat. With the establishment and improvement of transformation platform, great progresses have been made on wheat genetic transformation both on its fundamental and applied studies in China, especially driven by the National Major Project for Transgenic Organism Breeding, China, initiated in 2008. In this review, wheat genetic transformation platform improvement and transgenic research progresses including new techniques applied and functional studies of wheat quality, yield and stress tolerant related genes and biosafety assessment are summarized. The existing problems and the trends in wheat transformation with traditional methods combined with genomic studies and genome editing technology are also discussed.

关键词： genetic modification quality stress tolerance transformation platform wheat

考虑时空协同优先的城市应急车辆路径优化方法

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公路交通科技 2024年第3期41卷 169-178,198页

作者：郝正博杨晓光王一喆高乃航苏岳龙同济大学道路与交通工程教育部重点实验室上海201804 上海市消防救援总队上海200051 高德软件有限公司北京102299

目前城市应急救援车辆救援效能提升面临交通拥堵、交叉口延误、突发事故等诸多挑战。传统路径算法忽略了实际救援工作需求和路径选择偏好特征,无法很好满足快速高效、安全可靠的救援需求。针对这一问题,立足应急车辆与社会车辆在优先通... 详细信息

目前城市应急救援车辆救援效能提升面临交通拥堵、交叉口延误、突发事故等诸多挑战。传统路径算法忽略了实际救援工作需求和路径选择偏好特征,无法很好满足快速高效、安全可靠的救援需求。针对这一问题,立足应急车辆与社会车辆在优先通行政策、车辆特性、优化目标、路径选择偏好等多特征差异,提出一种考虑时空协同优先的两阶段应急车辆救援路径动态优化方法。第1阶段,将用于求解静态K最短路径的Yen算法与城市路网时空动态性、高度随机性及不确定性等特征结合,增加基于层次聚类算法的路径安全风险约束与基于偏斜度指数等综合评价指标的可靠性约束,构建带有安全可靠性约束的动态K最短路径精确算法。第2阶段,结合车道数量、路段限速、路段长度等静态属性特征与拥堵延迟指数、路段平均车速等动态属性特征,求解在时空协同优先条件下的最佳救援路径。结果表明:与历史救援轨迹相比,考虑时空协同优先的两阶段城市应急车辆路径优化方法能够有效缩短城市应急车辆的救援响应时间,并提高应急车辆救援安全性与可靠性。因此,本方法面向实际救援工作,具有较好的应用前景。

关键词：城市交通路径动态优化时空协同优先应急车辆安全风险可靠性

双能CT定量参数在肺癌病理特征中的诊断价值

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中国CT和MRI杂志 2024年第9期22卷 168-169+176页

作者：徐艳秋杨晓光史洁郑州市第九人民医院呼和浩特市第一医院医学影像科

在我国,肺癌发病率及死亡率均较高,肺癌不同病理学分型发生发展的特征各不相同,因此准确诊断肺癌不同病理亚型,可以精确治疗手段,对患者生存时间及生存质量具有较高价值。近年来,双能量CT作为一种功能成像方式,已较多应用于临床,其定量... 详细信息

在我国,肺癌发病率及死亡率均较高,肺癌不同病理学分型发生发展的特征各不相同,因此准确诊断肺癌不同病理亚型,可以精确治疗手段,对患者生存时间及生存质量具有较高价值。近年来,双能量CT作为一种功能成像方式,已较多应用于临床,其定量参数对肺癌病理类型诊断、基因特征分析等具有重要意义。本文将探讨关于双能量CT相关定量参数对肺癌不同病理类型的诊断效能。

关键词：双能量CT 肺癌病理特征基因突变免疫组化

妇幼保健机构营养服务及当地母婴营养状况分析

同方期刊数据库博看期刊评论

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营养学报 2024年第3期46卷 220-227页

作者：王杰赵文华宋鹏坤庞学红杨晓光杨振宇赖建强陈君石中国疾病预防控制中心营养与健康所中国疾病预防控制中心母乳科学研究重点实验室国家卫生健康委员会公共营养与健康重点实验室北京100050 国家食品安全风险评估中心北京100022

目的探讨妇幼保健机构营养服务现状及与母婴营养健康的关系。方法于2020年利用网络信息检索的方式,对全国441家省级、直辖市市辖区、地级市妇幼保健机构的营养服务进行调查。基于中国0~17岁儿童青少年与乳母营养健康监测(2016-2017年)... 详细信息

目的探讨妇幼保健机构营养服务现状及与母婴营养健康的关系。方法于2020年利用网络信息检索的方式,对全国441家省级、直辖市市辖区、地级市妇幼保健机构的营养服务进行调查。基于中国0~17岁儿童青少年与乳母营养健康监测(2016-2017年)中部分儿童和乳母数据,分析有无营养服务地区的母婴营养健康状况差异。结果246家地市级及以上妇幼保健机构设有官方网站,为孕产妇和儿童提供了营养服务的比例分别为49.6%和53.3%,仅3.3%的机构设置了专职营养服务人员。孕产妇营养服务隶属于保健科、妇产科和营养科的比例分别占45.9%、39.3%和14.8%;儿童营养服务主要隶属于儿童保健科,占93.9%。与没有为母婴提供营养服务的地区相比,妇幼保健机构为母婴提供营养服务的地区母亲孕期体重增长过多风险较低(P<0.05),产后血脂异常、维生素D缺乏、血清白蛋白和总蛋白过低的风险较低(P<0.05);儿童超重的风险较低(P<0.05),6月龄内儿童基本纯母乳喂养的比例较高(P<0.05)。结论妇幼保健机构营养服务覆盖率低,不利于母婴营养与健康。建议落实国家相关政策,完善营养科室设置与人员配置;建立营养服务相关标准,服务花费纳入医保支付体系;稳定、深化和拓展营养服务内容,促进母婴健康。

关键词：营养服务儿童营养不良母亲健康营养监测