检索结果-南通市图书馆

Measuring Spatial Differences of Informatization in China

在线全文

学校读者我要写书评

暂无评论

Chinese Geographical Science 2014年第6期24卷 717-731页

作者： SONG Zhouying LIU Weidong ma Li michael DUNFORD Key Laboratory of Regional Sustainable Development Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences School of Global Studies University of Sussex Brighton BN1 9QNUK

As the wide application of new Information and Communication Technologies(ICTs) shows, the world is moving fast towards an information age. Since China was first connected to the Internet in 1994, the development of ICTs in China and around the world has been astonishingly fast, and yet there is a clear ′digital divide′ among different regions in China. Although Chinese geographers have paid attention to regional differences in informatization, they usually employ a limited number of indicators, mainly focusing on the Internet. In fact, informatization is a much broader concept, covering not only the Internet, but also mobile phones as well as user ability. In the light of these considerations, this study provides a comprehensive examination of the development of informatization and its spatial differences in China. First, based on a literature review, the paper identifies 29 preliminary indicators for measuring informatization, and employs principal components analysis and the fuzzy analytic hierarchy process to streamline them into 12 indicators to form an ICTs Development Index(IDI). Second, by using the data from provincial statistical yearbooks and the China Internet Network Information Center, the paper calculates the IDI of each mega-region and each province in 2000–2010, and measures the changing spatial differences in the development of informatization in China. Lastly, the paper quantifies the relationship between informatization and economic growth. The empirical results show that the IDI of the western and central China has been increasing faster than that of the coastal region, indicating that the digital divide in China has been narrowing.

关键词：中国互联网络信息中心空间差异信息化信息通信技术模糊层次分析法测量信息 TiAl基中西部地区

A well-supported nuclear phylogeny of Poaceae and implications for the evolution of C4 photosynthesis

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2022年第4期15卷 755-777页

作者： Weichen Huang Lin Zhang JTravis Columbus Yi Hu Yiyong Zhao Lin Tang Zhenhua Guo Wenli Chen michael McKain madelaine Bartlett Chien-Hsun Huang De-Zhu Li Song Ge Hong ma Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkState CollegePA 16802USA Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering and State Key Laboratory of Genetic Engineering Institute of Biodiversity Sciences and Institute of Plant BiologySchool of Life SciencesFudan University2005 Songhu RoadShanghai 200438China Rancho Santa Ana Botanic Garden and Claremont Graduate University 1500 North College AvenueClaremontCA 91711USA College of Life Sciences Zhejiang UniversityHangzhouZhejiang 310058China Plant Germplasm and Genomics Center Germplasm Bank of Wild SpeciesKunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201 China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China Department of Biological Sciences University of Alabama411 Mary Harmon Bryant HallTuscaloosaAL 35487USA Biology Department University of Massachusetts Amherst611 North Pleasant Street221 Morrill 3AmherstMA 01003 USA

Poaceae(the grasses)includes rice,maize,wheat,and other crops,and is the most economically important angiosperm *** is also one of the largest plant families,consisting of over 11000 species with a global distribution that contributes to diverse *** species are classified into 12 subfamilies,with generally strong phylogenetic support for their ***,many relationships within subfamilies,among tribes and/or subtribes,remain *** better resolve the Poaceae phylogeny,we generated 342 transcriptomic and seven genomic datasets;these were combined with other genomic and transcriptomic datasets to provide sequences for 357 Poaceae species in 231 genera,representing 45 tribes and all 12 *** 1200 low-copy nuclear genes were retrieved from these datasets,with several subsets obtained using additional criteria,and used for coalescent analyses to reconstruct a Poaceae *** results strongly support the monophyly of 11 subfamilies;however,the subfamily Puelioideae was separated into two non-sister clades,one for each of the two previously defined tribes,supporting a hypothesis that places each tribe in a separate *** clock analyses estimated the crown age of Poaceae to be101 million years *** character reconstruction of C3/C4 photosynthesis supports the hypothesis of multiple independent origins of C4 *** origins are further supported by phylogenetic analysis of the ppc gene family that encodes the phosphoenolpyruvate carboxylase,which suggests that members of three paralogous subclades(ppc-aL1a,ppc-aL1b,and ppcB2)were recruited as functional C4 ppc *** study provides valuable resources and a robust phylogenetic framework for evolutionary analyses of the grass family.

关键词： Gramineae transcriptome nuclear phylogeny molecular clock C4 photosynthesis ppc gene evolution

Exceptionally Preserved Conodont Natural Assemblages from the Middle Triassic Luoping Biota,Yunnan Province,China:Implications for Architecture of Conodont Feeding Apparatus

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2023年第6期34卷 1762-1776页

作者： Jinyuan Huang Carlos martinez-Perez Qiyue Zhang Kexin Zhang mao Luo Wen Wen Changyong Zhou Xiao Min Zhixin ma Tao Xie michael J.Benton Philip C.J.Donoghue Chengdu Center China Geological Survey(Geosciences Innovation Center of Southwest China)Chengdu 610081China Cavanilles Institute of Biodiversity&Evolutionary Biology University of Valencia46980 ValenciaSpain Institute of Geological Survey China University of GeosciencesWuhan 430074China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China School of Ocean Sciences China University of GeosciencesBeijing 100083China School of Earth Sciences University of BristolBristol BS81TQUK

Articulated natural assemblages contain direct evidence of the element numbers,morphologies,positions and structures for reconstructing the feeding apparatuses of conodont animals,but these kind of materials are very rare in fossil *** we report ten new conodont natural assemblages from Member II of the Guanling Formation in Luoping County,eastern Yunnan Province,southwestern *** assemblages were obtained from the fossil-bearing layers of the Luoping Biota,dated to the early Middle Triassic Anisian stage(Pelsonian substage).These fossiliferous laminated limestones mainly consist of calcites and dolomites,with platy clay minerals and pyrites as subordinate components,indicating that the conodont assemblages were preserved in a lower energy and anoxic sedimentary *** new natural assemblages preserve the primary collapse orientations of the Nicoraella feeding apparatus from the Luoping Biota,showing the relative original positions of the S,M and P elements,that could be further used to refine the architecture of this apparatus in space variable M elements and the position unclear P1 *** previously reported three-dimensional and bilaterally symmetrical fused clusters,we statistically analyze the size of the positional homogenous elements within different sized materials,in particular S4,S3,or S2 elements,indicates that elements ontogenic changes do not affect the apparatus *** of Nicoraella apparatus remains stable in the process of ontogeny,so our reconstructed model is *** is the first time that ample types of materials have been used to restore a conodont apparatus within one genus,namely natural assemblages(articulated and disarticulated),fused clusters(articulated,disarticulated,compressed,and relatively three-dimensional),and abundant discrete elements,*** materials together record the most complete information on architecture in the gondolelloid apparatuses,thus enabling us

关键词： conodont natural assemblage architecture fused cluster size variation limestone MiddleTriassic southwestern China

A Post-domestication Mutation, Dt2, Triggers Systemic Modification of Divergent and Convergent Pathways Modulating Multiple Agronomic Traits in Soybean

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2019年第10期12卷 1366-1382页

作者： Dajian Zhang Xutong Wang Shuo Li Chaofan Wang michael JGosney michael VMickelbart Jianxin ma Department of Agronomy Purdue UniversityWest LafayetteIN 47907USA College of Agronomy Shandong Agricultural UniversityTai'anShandong 271018China School of Life Sciences Shandong UniversityQingdaoShandong 266237China Department of Botany and Plant Pathology Purdue UniversityWest LafayetteIN 47907USA Center for Plant Biology Purdue UniversityWest LafayetteIN 47907USA

The semi-determinate stem growth habit in leguminous crops,similar to the“green revolution”semi-dwarf trait in cereals,is a key plant architecture trait that affects several other traits determining grain *** soybean semi-determinacy is modulated by a post-domestication gain-of-function mutation in the gene,Dt2,which encodes an maDS-box transcription ***,its role in systemic modification of stem growth and other traits is *** this study,we show that Dt2 functions not only as a direct repressor of Dt1,which prevents terminal flowering,but also as a direct activator of putative floral integrator/identity genes including GmSOC1,GmaP1,and GmFUL,which likely promote *** also demonstrate that Dt2 functions as a direct repressor of the putative drought-responsive transcription factor gene GmDREB1D,and as a direct activator of GmSPCH and GmGRP7,which are potentially associated with asymmetric division of young epidermal cells and stomatal opening,respectively,and may affect the plant's water-use efficiency(WUE).Intriguingly,Dt2 was found to be a direct activator or repressor of the precursors of eight microRNAs targeting genes potentially associated with meristem maintenance,flowering time,stomatal density,WUE,and/or stress *** study thus reveals the molecular basis of pleiotropy associated with plant productivity,adaptability,and environmental resilience.

关键词： abiotic stress agronomic traits convergent pathways stem growth habit pleiotropy soybean

EFFICIENT BOX-CONSTRAINED TV-TYPE-l^1 ALGORITHMS FOR RESTORING ImaGES WITH IMPULSE NOISE

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2013年第3期31卷 249-270页

作者： Liyan ma michael K. Ng Jian Yu Tieyong Zeng School of Computer and Information Technology Beijing Jiaotong University Beijing 100044 China Department of mathematics Hong Kong Baptist University Hong Kong China

In this paper, we study the restoration of images simultaneously corrupted by blur and impulse noise via variational approach with a box constraint on the pixel values of an image. In the literature, the TV-l^1 variational model which contains a total variation （TV） regularization term and an l^1 data-fidelity term, has been proposed and developed. Several numerical methods have been studied and experimental results have shown that these methods lead to very promising results. However, these numerical methods are designed based on approximation or penalty approaches, and do not consider the box constraint. The addition of the box constraint makes the problem more difficult to handle. The main contribution of this paper is to develop numerical algorithms based on the derivation of exact total variation and the use of proximal operators. Both one-phase and two-phase methods are considered, and both TV and nonlocal TV versions are designed. The box constraint [0, 1] on the pixel values of an image can be efficiently handled by the proposed algorithms. The numerical experiments demonstrate that the proposed methods are efficient in computational time and effective in restoring images with impulse noise.

关键词： Image restoration Impulse noise Total variation Nonlocal total variation Proximal Operators.

基于等几何分析的太阳帆板热结构耦合随机动力响应

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2023年第4期39卷 72-83页

作者：马娟代昌平王博 michael Beer 王安意 Research Center of Applied Mechanics School of Electro-Mechanical EngineeringXidian UniversityXi’an710071China Shaanxi Key Laboratory of Space Extreme Detection Xidian UniversityXi’an710071China Institute for Risk and Reliability Faculty of Civil Engineering and Geodetic ScienceLeibniz Universität HannoverCallinstr.3430900HannoverGermany

航天器周期性地出入日光区和背光区,会受到太阳辐射而引起周期性热应力的影响.基于等几何分析法,研究了具有随机场参数的太阳能帆板在热结构耦合下的随机动力响应.首先基于非均匀有理B样条构造了帆板的几何模型,得到太阳能帆板的热传导... 详细信息

航天器周期性地出入日光区和背光区,会受到太阳辐射而引起周期性热应力的影响.基于等几何分析法,研究了具有随机场参数的太阳能帆板在热结构耦合下的随机动力响应.首先基于非均匀有理B样条构造了帆板的几何模型,得到太阳能帆板的热传导微分方程和振动微分方程;利用Newmark-β法求解了热-结构耦合下的微分方程,得到结构温度场和随机动力响应;最后,研究了不同随机场参数对结构动力响应的影响.

关键词：非均匀有理B样条随机动力响应热结构耦合太阳能帆板振动微分方程等几何分析结构动力响应太阳帆板

Temperature and velocity dependent friction of a microscale graphite-DLC heterostructure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2020年第2期8卷 462-470页

作者： Yujie GONGYANG Wengen OUYANG Cangyu QU michael URBAKH Baogang QUAN Ming ma Quanshui ZHENG Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China Center for Nano and Micro Mechanics Tsinghua UniversityBeijing 100084China School of Chemistry and The Sackler Center for Computational Molecular and materials Science Tel Aviv UniversityTel Aviv 69978Israel The Raymond and Beverly Sackler Faculty of Exact Sciences Tel Aviv UniversityTel Aviv 69978Israel Beijing National Laboratory for Condensed matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China

One of the promising approaches to achieving large scale superlubricity is the use of junctions between existing ultra-flat surface together with superlubric graphite *** we studied the frictional properties of microscale graphite mesa sliding on the diamond-like carbon,a commercially available material with a ultra-flat *** interface is composed of a single crystalline graphene and a diamond-like carbon surface with roughness less than I *** an integrated approach,which includes Argon plasma irradiation of diamond-like carbon surfaces,X-ray photoelectron spectroscopy analysis and Langmuir adsorption modeling,we found that while the velocity dependence of friction follows a thermally activated sliding mechanism,its temperature dependence is due to the desorption of chemical groups upon *** observations indicate that the edges have a significant contribution to the *** results highlight potential factors affecting this type of emerging friction junctions and provide a novel approach for tuning their friction properties through ion irradiation.

关键词： friction graphite diamond like carbon irradiation desorption

Seroprevalence of influenza viruses in Shandong,Northern China during the COVID-19 pandemic

在线全文

学校读者我要写书评

暂无评论

Frontiers of Medicine 2022年第6期16卷 984-990页

作者： Chuansong Quan Zhenjie Zhang Guoyong Ding Fengwei Sun Hengxia Zhao Qinghua Liu Chuanmin ma Jing Wang Liang Wang Wenbo Zhao Jinjie He Yu Wang Qian He michael J.Carr Dayan Wang Qiang Xiao Weifeng Shi Key Laboratory of Etiology and Epidemiology of Emerging Infectious Diseases in Universities of Shandong Shandong First Medical University&Shandong Academy of Medical SciencesTaian 271000China School of Public Health Shandong First Medical University&Shandong Academy of Medical SciencesJinan 250117China The Department of Infectious Disease The Second Affiliated Hospital of Shandong First Medical UniversityTaian 271000China Clinical Laboratory The Department of Clinical LaboratoryBoshan District HospitalZibo 255200China Clinical Laboratory The Department of Clinical LaboratoryThe Second Affiliated Hospital of Shandong First Medical UniversityTaian 271000China The Department of Cancer Center Taian Tumor Prevention and Treatment HospitalTaian271000China National Virus Reference Laboratory School of MedicineUniversity College DublinDublin 4Ireland International Collaboration Unit International Institute for Zoonosis ControlHokkaido UniversitySapporoHokkaido0010020Japan Chinese National Influenza Center National Institute for Viral Disease Control and PreventionCollaboration Innovation Center for Diagnosis and Treatment of Infectious DiseasesChinese Center for Disease Control and PreventionKey Laboratory for Medical VirologyNational Health and Family Planning CommissionBeijing102206China

Nonpharmaceutical interventions(NPIs)have been commonly deployed to prevent and control the spread of the coronavirus disease 2019(COVID-19),resulting in a worldwide decline in influenza ***,the influenza risk in China warrants cautious *** conducted a cross-sectional,seroepidemiological study in Shandong Province,Northern China in *** inhibition was performed to test antibodies against four influenza vaccine strains.A combination of descriptive and meta-analyses was adopted to compare the seroprevalence of influenza antibodies before and during the COVID-19 *** overall seroprevalence values against A/H1N1pdm09,A/H3N2,B/Victoria,and B/Yamagata were 17.8%(95%CI 16.2%–19.5%),23.5%(95%CI 21.7%–25.4%),7.6%(95%CI 6.6%–8.7%),and 15.0(95%CI 13.5%–16.5%),respectively,in the study *** overall vaccination rate was extremely low(2.6%).Our results revealed that antibody titers in vaccinated participants were significantly higher than those in unvaccinated individuals(Pmaintaining NPIs are recommended to prevent an elevated influenza risk in China.

关键词： influenza virus seroprevalence antibody COVID-19 cross-sectional study

北极地区气候变暖对莎草地上和地下部分物候和生物量的影响

在线全文

学校读者我要写书评

暂无评论

Journal of Plant Ecology 2022年第5期15卷 1091-1105页

作者： Ting ma Thomas Parker Ned Fetcher Steven L.Ungers Jon Gewirtzman michael L.Moody Jianwu Tang The Ecosystems Center Marine Biological LaboratoryWoods HoleMA 02543USA College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China Department of Biological and Environmental Sciences Faculty of Natural SciencesUniversity of StirlingStirlingUK Institute for Environmental Science and Sustainability Wilkes UniversityWilkes-BarrePA 18766USA Department of Biological Sciences Florida International UniversityMiamiFL 33199USA Yale School of the Environment New HavenCT 06520USA Department of Biological Sciences University of Texas at El PasoEl PasoTX 79968USA

北极地区的土壤和植被中存储了大量的碳,在气候变化的大背景下,北极升温速度几乎是地球其他地区的2倍。由于缺乏同步测量,尚不清楚北极地区植被地上部分和地下部分的物候和生物量对气候变化的反应。在2016和2017年的生长季节,我们在北极... 详细信息

北极地区的土壤和植被中存储了大量的碳,在气候变化的大背景下,北极升温速度几乎是地球其他地区的2倍。由于缺乏同步测量,尚不清楚北极地区植被地上部分和地下部分的物候和生物量对气候变化的反应。在2016和2017年的生长季节,我们在北极的Toolik Lake站点上建立了一个移植花园,并沿纬度变化从高到低依次从Sagwon、Toolik Lake和Coolfoot这3个站点移植了3种不同生态类型的莎草(Eriophorum vaginatum)。一半莎草用作增温处理,另一半为控制处理。我们用物候相机、手持式光谱仪和微根窗分别观测3种生态型莎草的绿色度、归一化植被指数(NDVI)和根长动态,根据NDVI和根长计算了叶片和细根的生物量。研究发现,莎草的叶和根生长是异步的,叶片开始生长的时间比根系生长的时间早约28天。气温升高1℃会延迟叶片衰老的时间,从而延长生长期,但温度升高对根系物候没有显着影响,变暖在统计学上没有增加叶片和根的生物量。此外,叶片生长的季节动态受气温的影响,但根的生长与土壤融化深度有关。因此,我们建议在使用碳和养分循环模型时,应将叶和根成分分开考虑,因为地上和地下的以及功能属性可能对气候变暖有不同的反应。

关键词：莎草物候气候变暖地上生物量地下生物量