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The number of births in china in 2015： policy meets superstition

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Science Bulletin 2018年第19期63卷 1235-1237页

作者： Hong-Tian Li Susan Hellerstein Chuyun kang Leonardo Trasande Yanqiu Gao Yali Zhang Shusheng Luo Yu-Bo Zhou Jie Qiao Jan Blustein Jian-Meng Liu Institute of Reproductive and Child Health. National Health Commission Key Laboratory of Reproductive Health Peking University Health Science Center Beijing 100191 China Office for National Maternal and Child Health Statistics of china. School of Public Health Peking University Health Science Center Beijing 100191 China Department of Epidemiology and Biostatistics School of Public Health Peking University Health Science Center Beijing 100191 China Department of Obstetrics and Gynecology Brigham and Women's Hospital Harvard Medical School Boston MA 02115 USA Department of Child Adolescent and Women's Health School of Public Health Peking University Health Science Center Beijing 100191 China Departments of Pediatrics and Environmental Medicine NYU School of Medicine NY 100016 USA Department of Population Health NYU School of Medicine NY 100016 USA NYU Wagner School of Public Service NY 100012 USA Department of Obstetrics and Gynecology Center for Reproductive Medicine Peking University Third Hospital. Beijing 100191 China Key Laboratory of Assisted Reproduction Ministry of Education Beijing 100191 China Reproductive Health Research Center of Peking University Health Science Center Belting 100191 China

Fertility in china was long constrained by the One-Child policy enacted in 1978. Over time the policy was progressively relaxed,first in rural areas and then for couples who both had no siblings.A Selective Two-Child policy which started in January-June 2014allowed a second child for couples for whom one spouse was an only child. Now with the Universal Two-Child policy, as of

关键词：中国迷信独生子女孩子

Functional diversity and redundancy of subalpine meadows subjected to anthropogenic disturbances

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Journal of Plant Ecology 2021年第5期14卷 870-883页

作者： Xiaoxia Huang Zhilu Sheng Kejian He Yong Zhang Bin kang Jiao Ding Dongmei Liu Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region School of Earth SciencesYunnan UniversityKunming 650091Cliina State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment Institute of Ecology ResearchChinese Research Academy of Environmental SciencesBeijing 100012China National Plateau Wetlands Research Center College of WetlandsSoutliwest Forestry UniversityKunming 650224China College of Fisheries Ocean University of ChinaQingdao 266003China Water Conservancy Department of Yunnan Province Kunming 650021China

Aims The aims of this study were to assess how functional diversity(FD)and functional redundancy respond to subalpine meadow ecosystem degradation under anthropogenic disturbance and how species contribute to functional redundancy along the disturbance *** The study was carried out in the subalpine meadow in Mount Jade Dragon,which is located at the southeastern edge of the Tibetan *** disturbance intensities[no disturbance(ND),weak disturbance(WD),moderate disturbance(MD)and severe disturbance(SD)]were *** richness,soil properties and five key plant functional traits were assessed along the disturbance ***’s diversity index,FD based on the Rao algorithm,functional redundancy,community-weighted mean of each functional trait and species-level functional redundancy were *** Findings Unimodal change pattern of FD and functional redundancy along the disturbance gradient were found in the present study,with their maximum in MD and WD,*** diversity showed a decreasing trend with increasing disturbance *** disturbance intensified,species with traits related to conservative growth strategies,such as low specific leaf area(SLA)and high leaf dry matter content(LDMC),decreased,whereas species with resource acquisitive strategies,such as small plant,high SLA and low LDMC,increased in the *** the species level,species showed species-specific roles in functional ***,some species were important in the community in terms of their unique *** instance,Ligularia dictyoneura in ND and Potentilla delavayi in MD and SD.

关键词： anthropogenic disturbance functional diversity functional redundancy functionally unique species subalpine meadow

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中国射电天文观测和研究展望

北京师范大学学报（自然科学版） 2005年第3期41卷 268-270页

作者：康连生中国科学院国家天文台北京100012

综述了中国射电天文观测和研究状况,展望射电天文观测和研究的前景.介绍了中国射电天文观测的主要设备,为培养射电天文观测和研究人材提供相关信息.

关键词：射电天文观测研究中国

Fc fragment of immunoglobulin G receptor IIa(FCGR2A)as a new potential prognostic biomarker of esophageal squamous cell carcinoma

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chinese Medical Journal 2022年第4期135卷 482-484页

作者： Sifen Lu Nan Li Zhiqiang Peng Zuhong Lu Xingyue Tu Wengeng Zhang Yulin kang Precision Medicine Key Laboratory of Sichuan Province and Precision Medicine Center West China HospitalSichuan UniversityChengduSichuan 610041China Department of Information Center and National Clinical Research Center for Geriatrics West China HospitalSichuan UniversityChengduSichuan 610041China State Key Laboratory of Proteomics National Center for Protein Sciences(Beijing)Beijing Institute of LifeomicsBeijing 100850China State Key Lab of Bioelectronics National Demonstration Center for Experimental Biomedical Engineering EducationSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjingJiangsu 210096China Institute of Environmental Information Chinese Research Academy of Environmental SciencesBeijing 100012China

To the Editor: Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive cancer types and places a heavy burden on human health. The early diagnosis and prognosis monitoring of ESCC is important for therapy. Despite recent progress in treatment regimens for ESCC, the prognosis of ESCC remains poor.[1] Therefore, it is important to find new molecular therapeutic targets and prognostic monitoring biomarkers for ESCC patients. In this study, we aimed to explore new prognostic biomarkers for ESCC.

关键词： squamous prognosis esophageal

Impacts of Indian summer monsoon and stratospheric intrusion on air pollutants in the inland Tibetan Plateau

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Geoscience Frontiers 2021年第6期12卷 294-298页

作者： Xiufeng Yin Shichang kang Benjamin de Foy Dipesh Rupakheti Maheswar Rupakheti Zhiyuan Cong Xin Wanb Guoshuai Zhang Qianggong Zhang State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of chinese academy of sciences Beijing 100049China Center for Excellence in Tibetan Plateau Earth sciences Chinese Academy of SciencesBeijing 100101China Department of Earth and Atmospheric sciences Saint Louis UniversitySt.LouisMO 63108USA Institute for Advanced Sustainability Studies PotsdamGermany chinese academy of Environmental Planning Beijing 100012China

Air pollutants can be transported to the pristine regions such as the Tibetan Plateau,by monsoon and stratospheric *** Tibetan Plateau region has limited local anthropogenic emissions,while this region is influenced strongly by transport of heavy emissions mainly from South *** conducted a comprehensive study on various air pollutants (PM_(2.5),total gaseous mercury,and surface ozone) at Nam Co Station in the inland Tibetan *** mean PM_(2.5)concentration at Nam Co peaked in April before monsoon season,and decreased during the whole monsoon season (June–September).Monthly mean total gaseous mercury concentrations at Nam Co peaked in July and were in high levels during monsoon *** Indian summer monsoon acted as a facilitator for transporting gaseous pollutants (total gaseous mercury) but a suppressor for particulate pollutants (PM_(2.5)) during the monsoon *** from both PM_(2.5)and total gaseous mercury variabilities,surface ozone concentrations at Nam Co are primarily attributed to stratospheric intrusion of ozone and peaked in *** effects of the Indian summer monsoon and stratospheric intrusion on air pollutants in the inland Tibetan Plateau are complex and require further studies.

关键词： Tibetan Plateau Nam Co PM_(2.5) Total gaseous mercury Surface ozone

A New Solar Radio Spectrometer at 1.10-2.06 GHz and First Observational Results

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chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 433-441页

作者： Hui-Rong Ji Qi-Jun Fu Yi-Hua Yan Yu-Ying Liu Zhi-Jun Chen Cheng-Ming Tan Cong-Ling Cheng De-Bang Lao Shu-Ke Li Zhi-Qiang Wang Min-Hong Yu Jian-Nong Liu Li-kang Zhang Ji-Yong Gao National astronomical observatories Chinese Academy of Sciences Beijing 100012 Hebei Semiconductor Research Institute Shijiazhuang 050051

An improved Solar Radio Spectrometer working at 1.10-2.06 GHz with much improved spectral and temporal resolution, has been accomplished by the National astronomical observatories and Hebei Semiconductor Research Institute,based on an old spectrometer at 1 2 GHz. The new spectrometer has a spectral resolution of 4 MHz and a temporal resolution of 5 ms, with an instantaneous detectable range from 0.02 to 10 times of the quiet Sun flux. It can measure both left and right circular polarization with an accuracy of 10% in degree of polarization. Some results of preliminary observations that could not be recorded by the old spectrometer at 1-2 GHz are presented.

关键词： instrumentation: spectrometer - sun: radio radiation

基于激光切割技术的科技馆文创产品开发实践研究--以“记里鼓车拼装玩具”为例

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今日科苑 2022年第1期 51-59页

作者：陈康中国科学技术馆北京100012

科技馆开发文创产品,能够更好地实现自身的社会功能,对于延伸科技馆科普教育功能、满足公众对科普事业的需求具有重要意义。激光切割技术,作为一种加工制作方法,为文创产品研发设计提供了技术支持。本文基于激光切割技术的文创产品(拼... 详细信息

科技馆开发文创产品,能够更好地实现自身的社会功能,对于延伸科技馆科普教育功能、满足公众对科普事业的需求具有重要意义。激光切割技术,作为一种加工制作方法,为文创产品研发设计提供了技术支持。本文基于激光切割技术的文创产品(拼插玩具)的开发实践,阐述激光切割技术在文创产品开发中的应用、科普文创产品设计理念与开发策略、自研科普文创产品研发思路与开发流程等,以期对科技馆行业内的文创产品开发工作有所启示。

关键词：激光切割科技馆文创产品开发实践

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煤层瓦斯含量井下一站式自动化精准测定方法

煤炭学报 2022年第8期47卷 2873-2882页

作者：周福宝康建宏王有湃张冉中国矿业大学安全工程学院江苏徐州221116 中国安全生产科学研究院北京100012

煤层瓦斯含量是预测煤与瓦斯突出危险性和评价矿井瓦斯储量的基础参数。针对现有测定方法需要井上和井下分阶段测量、测定周期长的不足,提出了煤层瓦斯含量井下一站式自动化测定新方法,介绍了煤样井下直接破碎系统、瓦斯解吸量自动化计... 详细信息

煤层瓦斯含量是预测煤与瓦斯突出危险性和评价矿井瓦斯储量的基础参数。针对现有测定方法需要井上和井下分阶段测量、测定周期长的不足,提出了煤层瓦斯含量井下一站式自动化测定新方法,介绍了煤样井下直接破碎系统、瓦斯解吸量自动化计量系统和数据自动采集处理系统等关键单元构成及主要技术指标。其次,针对现有测定方法中损失瓦斯量估算误差大的难题,考虑煤孔隙结构的非均匀性建立了瓦斯分数阶扩散模型,以此准确推算煤样暴露过程的损失瓦斯量;搭建了模拟井下煤层瓦斯含量测定流程的误差分析系统,通过设定不同吸附平衡压力来改变瓦斯含量,设定不同暴露时间来改变损失瓦斯量,并通过与传统模型对比来验证分数阶模型的准确性。实验表明,分数阶模型推算损失瓦斯量的误差在10%以内,测定瓦斯含量的误差在5%以内,而传统■模型和幂函数模型测定瓦斯含量的误差达到20%以上。最后,基于煤层瓦斯含量井下一站式自动化测定方法,研发了CWH12型煤层瓦斯含量测定仪,在淮南矿区朱集东矿和潘三矿进行了现场应用,并使用煤矿原有瓦斯含量测定设备对同一地点、同一深度的煤样进行了测定比较。现场试验表明,CWH12型煤层瓦斯含量测定仪比原有设备的测定值平均提高了13.5%,测量时间缩短至1.5 h以内,实现了煤层瓦斯含量的快速精准测定。

关键词：煤层瓦斯含量直接测定方法损失瓦斯量测定装备快速测定

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基于光散射法粉尘个体监测仪研制

中国安全生产科学技术 2021年第6期17卷 149-153页

作者：付士根亢永王庆中国安全生产科学研究院北京100012 北京石油化工学院安全工程学院北京102617

为研制矿山呼吸性粉尘浓度个体监测仪,采用MIE光散射方法,试制以红外线发光二极管作为光源的呼吸性粉尘浓度个体监测仪,该监测仪主要由气路部分、光路部分及电路部分组成。利用中国安全生产科学研究院自制的粉尘简易试验装置,在气体流量... 详细信息

为研制矿山呼吸性粉尘浓度个体监测仪,采用MIE光散射方法,试制以红外线发光二极管作为光源的呼吸性粉尘浓度个体监测仪,该监测仪主要由气路部分、光路部分及电路部分组成。利用中国安全生产科学研究院自制的粉尘简易试验装置,在气体流量为2 L/min、颗粒粒径不大于5μm的条件下,研究试制仪器电压输出值和流入粉尘质量浓度二者的对应关系。结果表明:根据不同粉尘质量浓度下的输出电压数据,在0~300 mg/m^(3)测量范围内,试制仪器输出电压值和粉尘浓度之间具有线性函数关系,说明呼吸性粉尘浓度个体监测仪是合理可行的;粉尘监测仪测试结果与比对仪器测量结果对比分析可知,测量误差最大为1.59%,满足粉尘检定规程要求。

关键词：呼吸性粉尘光散射个体监测仪误差分析