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Applied Mathematics and Mechanics(English Edition) 1991年第9期12卷 881-890页

作者： Xu Da-peng julian Hunt Institute of Mechanics Chinese Academy of SciencesBeijing Department of Applied Mathematics and Theoretical Physics University of CambridgeCambridgeBritain

A general four-layer structure linear theory for predicting the effects of arbitrarily distributed roughness change on the variations of wind speed and shear stress in the surface layer of 3D and 2D atmospheres was **... 详细信息

关键词： atmospheric boundary layer surface roughness

麦二叉蚜唾液蛋白基因Sg1655时空表达谱及其抑制小麦防御反应的功能

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植物保护学报 2024年第1期51卷 20-27页

作者：孙钰张雨濛刘晓蓓陈巨莲张勇解海翠河北科技师范学院河北省作物逆境生物学重点实验室秦皇岛066600 中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193

为进一步明确麦二叉蚜Schizaphis graminum唾液蛋白Sg1655在调控小麦防御反应中的作用,基于麦二叉蚜唾液腺转录组数据,利用PCR技术克隆获取Sg1655开放阅读框,利用生物信息学软件对其序列进行分析;通过实时荧光定量PCR(real-time quantit... 详细信息

为进一步明确麦二叉蚜Schizaphis graminum唾液蛋白Sg1655在调控小麦防御反应中的作用,基于麦二叉蚜唾液腺转录组数据,利用PCR技术克隆获取Sg1655开放阅读框,利用生物信息学软件对其序列进行分析;通过实时荧光定量PCR(real-time quantitative PCR,RT-qPCR)技术检测Sg1655在麦二叉蚜不同组织及不同龄期中的表达;利用细菌III型分泌系统将Sg1655导入到小麦叶片内,检测其瞬时表达对小麦胼胝质积累的影响。结果表明,Sg1655开放阅读框全长375 bp,编码125个氨基酸残基,N端1~21位为信号肽序列,预测蛋白分子量为14.90 kD。麦二叉蚜Sg1655氨基酸序列与玉米蚜Rhopalosiphum maidis同源序列相致性最高,为89.52%;麦二叉蚜Sg1655与玉米蚜同源序列聚为一个分支,亲缘关系最近。Sg1655在麦二叉蚜各组织中均有表达,其中在唾液腺中表达量最高,Sg1655在麦二叉蚜各个龄期均有表达,且在不同龄期之间无显著差异。小麦叶片内Sg1655瞬时表达可显著抑制小麦胼胝质积累,表明该蛋白可作为潜在效应子参与抑制小麦防御反应。

关键词：麦二叉蚜唾液蛋白 Sg1655 基因克隆序列比对时空表达谱功能分析

Nickel nanoparticles supported on nitrogen-doped carbon nanotubes are a highly active,selective and stable CO_(2) methanation catalyst

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Journal of Energy Chemistry 2021年第3期30卷 323-331页

作者： julian Godde Mariia Merko Wei Xia Martin Muhler Laboratory of Industrial Chemistry Ruhr University BochumD-44780 BochumGermany

CO_(2) methanation using nickel-based catalysts has attracted large interest as a promising power-to-gas *** nanoparticles supported on nitrogen-doped CNTs with Ni loadings in the range from 10 wt% to 50 wt% were synthesized by impregnation,calcination and reduction and characterized by elemental analysis,X-ray powder diffraction,H_(2) temperature-programmed reduction,CO pulse chemisorption and transmission electron *** Ni/NCNT catalysts were highly active in CO_(2) methanation at atmospheric pressure,reaching over 50% CO_(2) conversion and over 95% CH_(4) selectivity at 340℃ and a GHSV of50,000 mL g^(-1) h^(-1) under kinetically controlled *** small Ni particle sizes below 10 nm despite the high Ni loading is ascribed to the efficient anchoring on the N-doped *** optimum loading of 30 wt%-40 wt% Ni was found to result in the highest Ni surface area,the highest degree of conversion and the highest selectivity to methane.A constant TOF of 0.3 s^(-1) was obtained indicating similar catalytic properties of the Ni nanoparticles in the range from 10 wt%to 50 wt% Ni ***-term experiments showed that the Ni/NCNT catalyst with 30 wt% Ni was highly stable for 100 h time on stream.

关键词： CO_(2)methanation Nickel nanoparticles Carbon nanotubes Nitrogen doping

Fused in sarcoma-amyotrophic lateral sclerosis as a novel member of DNA single strand break diseases with pure neurological phenotypes

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Neural Regeneration Research 2021年第1期16卷 110-112页

作者： Marcel Naumann julian Laubenthal Andreas Hermann Translational Neurodegeneration Section“Albrecht-Kossel” Department of NeurologyUniversity Medical Center RostockUniversity of RostockRostockGermany German Center for Neurodegenerative Diseases(DZNE)Rostock/Greifswald Center for Transdisciplinary Neurosciences Rostock(CTNR)University Medical Center RostockUniversity of RostockRostockGermany

Accumulation of DNA damage and genomic instability are believed to have crucial effects in neurodegenerative conditions such as Alzheimer’s disease,Parkinson’s disease,Huntington’s disease,premature aging diseases as well as amyotrophic lateral sclerosis(ALS)and frontotemporal dementia(FTD).Until recently these studies were largely correlative in nature,though raising the possibility that defects in the DNA damage response(DDR)underlie neurodegenerative diseases.

关键词： diseases Huntington amyotrophic

Buoyancy and turbulence-driven atmospheric circulation over urban areas

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Journal of Environmental Sciences 2017年第9期29卷 63-71页

作者： Yifan Fan julian Charles Roland Hunt Yuguo Li Department of Mechanical Engineering The University of Hong KongHong KongChina Department of Earth Sciences University College LondonLondonWC1E6BTUK Malaysian Commonwealth Studies Centre CambridgeCB23RFUK

In the buoyancy and turbulence-driven atmospheric circulations（BTDAC） that occur over urban areas where the approach means wind speeds are very low（less than turbulent fluctuations and typically 3 m/sec）, the surface temperatures are significantly higher than those in the external rural areas, and the atmosphere above the mixing layer is stably stratified. In this paper, the mechanisms of BTDAC formation are studied through laboratory experiments and modelling, with additional low-level inflow from external rural areas and a divergent outflow in the opposite direction in the upper part of the mixed layer. Strong turbulent plumes in the central region mix the flow between lower and higher levels up to the inversion height. There are shear-driven turbulent eddies and weaker buoyant plumes around the periphery of the urban area. As the approach flow is very weak,the recirculating streamlines within the dome restrict the ventilation, and the dispersion of pollution emitted from sources below the inversion height leading to a rise in the mean concentration. Low-level air entrained from rural areas can, however, improve ventilation and lower this concentration. This trend can also be improved if the recirculating structure of the BTDAC flow pattern over urban areas breaks down as a result of the surface temperature distribution not being symmetrical, or as the approach wind speed increases to a level comparable with the mean velocity of circulation, or（except near the equator） the urban area is large enough that the Coriolis acceleration is significant.

关键词： Urban heat island Buoyancy and turbulence-driven Eddy structures Atmospheric circulation Pollutant dispersion

The Perception of Flood Risks: A Case Study of Babessi in Rural Cameroon

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International Journal of Disaster Risk Science 2021年第4期12卷 458-478页

作者： Gertrud Buchenrieder julian Brandl Azibo Roland Balgah Research Center RISK Institute of Sociology and EconomicsUniversität der Bundeswehr München85577NeubibergGermany Leibniz Institute of Agricultural Development in Transition Economies(IAMO) 06120Halle(Saale)Germany TUM School of Life Sciences Weihenstephan Technical University Munich(TUM)85354MunichGermany College of Technology The University of Bamenda(UBa)BamendaNorth West RegionCameroon

Although risk perception of natural hazards has been identified as an important determinant for sound policy design,there is limited empirical research on it in developing *** article narrows the empirical literature *** draws from Babessi,a rural town in the Northwest Region of *** was hit by a severe flash flood in *** cross-disciplinary lens applied here deciphers the complexity arising from flood hazards,often embedded in contexts characterized by poverty,a state that is constrained in disaster relief,and market-based solutions being *** data were collected via snowball *** logistic regression analysis suggests that individuals with leadership functions,for example,heads of households,perceive flood risk higher,probably due to their role as household *** found that risk perception is linked to location,which in turn is associated with religious *** perceive floods riskier than Muslims because the former traditionally reside at the foot of hills and the latter uphill;rendering Muslims less exposed and eventually less affected by ***,public disaster relief appears to have built up trust and subsequently reduced risk perception,even if some victims remained skeptical of state disaster *** indicates strong potential benefits of public transfers for flood risk management in developing countries.

关键词： Flood disaster Multinomial logistic regression Risk perception Rural Cameroon

人力资本价值存量对创新发展的影响研究——来自深圳国家自主创新示范区的经验证据

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科技创业月刊 2024年第7期37卷 49-58页

作者：王佳蓉何菊莲湖南师范大学商学院湖南长沙410081

一直以来,我国十分重视创新发展进程。通过构建人力资本价值存量和创新发展的测评指标体系,基于深圳国家自主创新示范区(简称“自创区”)2009-2022年的数据,运用指数分析、回归分析和VAR模型研究人力资本价值存量对创新发展的影响。结... 详细信息

一直以来,我国十分重视创新发展进程。通过构建人力资本价值存量和创新发展的测评指标体系,基于深圳国家自主创新示范区(简称“自创区”)2009-2022年的数据,运用指数分析、回归分析和VAR模型研究人力资本价值存量对创新发展的影响。结果显示:(1)深圳自创区科技人力资本价值存量指数增长缓慢,尖端研发人员和技术人才仍有缺口;科技经费和R&D人才投入力度有待加强;(2)深圳自创区人力资本价值存量显著促进创新发展,人力资本价值存量每提高1个单位,创新发展提高1.009个单位;(3)人力资本价值存量3个维度对创新发展及其3个维度的影响效应呈增长趋势,滞后10期时,教育人力资本存量对创新发展的影响最强,为71.653%。基于以上结论提出对策建议,以期促进深圳自创区创新发展水平的进一步提高。

关键词：人力资本价值存量创新发展深圳国家自主创新示范区 VAR模型

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A Lagrangian mean theory on coastal sea circulation with inter-tidal transports ***

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Acta Oceanologica Sinica 2008年第6期27卷 1-16页

作者： FENG Shizuo julian JIANG Wensheng Key Laboratory of Physical Oceanography of Ministry of Education Institute of Physical Oceanography Ocean University ofChina Qingdao 266100 China

A brief review is made on the theory of the Lagrangian residual circulation and inter-tidal transports in a convectively weakly nonlinear system. In the review the emphasis is put on the systematical development of the theory and its weakness of convectively weakly nonlinear approximation. The fundamentals of a Lagrangian tidally-averaged theory on circulation with inter-tidal transport processes have been proposed for a general nonlinear coastal/estuarine system. The Lagrangian residual velocity is strictly de- fined, and it has been verified to be able to embody the velocity field of circulation. A new concept of the concentration for inter- tidal transport processes is presented. The concentration describing the inter-tidal transport processes should be a ＂Lagrangian inter-tidal concentration＂ defined and named, but not the Eulcrian tidally-averaged concentration used traditionally. The circulation described here contains a set of infinite temporal-spatial fields of velocity/concentration, each of which corresponds to a specific value of tidal phases varying continuously over one tidal cycle. When the convectively weakly nonlinear condition（ with a smaller order of eddy diffusion and sources） is approximately satisfied, a set of infinite temporal-spatial fields of velocity/concentration can be reduced to a single one.. the mass transport velocity/the Eulerian tidally averaged concentration as exhibited traditionally.

关键词： nonlinear shallow waters tide-dominating system coastal water circulation Lagrangian residual velocity Lagrangian inter-tidal concentration

Evolving concepts and opportunities in soil conservation

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International Soil and Water Conservation Research 2015年第1期3卷 1-14页

作者： julian Dumanski Consultant Sustainable Land ManagementOttawaCanada

The terrestrial landscape has changed considerably compared to that of the early 20th century when soil conservation was first *** portions of the land are already intensively managed,and the remainder is increasingly receiving human *** work on soil conservation focused attention on technological innovations,particularly control and mitigation of soil ***,land degradation has continued and actually accelerated in many parts of the world,due mainly to demands for continued economic development,using technologies that are highly *** many cases,this has been facilitated by highly inadequate and unsympathetic institutional,legislative,and policy *** paper discusses some of the new driving forces,new international programs,and new potential partners in soil ***,international efforts to mitigate land degradation are shifting from studies of the biophysical processes to improving the global,national and local enabling policy environment,as well as mainstreaming of soil conservation into national and regional policies and ***,increased emphasis is placed on economic instruments and international markets,such as carbon trading,and incorporation of non-market values in ecosystem investment,such as payment for ecosystem services,certification schemes,*** paper discusses some of the opportunities for soil conservation that accrue from these new driving forces.

关键词： Land degradation Environmental goods and services Driving forces

φ-meson photoproduction off the protons by using linearly polarized photons in the mid- to higher-t regimes at threshold energies

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Chinese Physics C 2009年第12期33卷 1349-1353页

作者： julian Salamanca Philip L. Cole Idaho State University Department of Physics Pocatello ID 83209-8106 USA Thomas Jefferson National Laboratory. Newport News VA 23606 USA

Observables from vector meson photoproduction by linearly-polarized photons can be expressed in term of bilinear combinations of helicity amplitudes parameterized by the Spin Density Matrix Elements （SDMEs）. These SDMEs give straightforward relations for understanding the nature of the parity exchange at threshold energies, as well as for extracting signatures of the Okubo-Zweig-Iizuka violation. This paper will show preliminary measurements of SDMEs for γp →φp in the photon energy range of 1.7 to 1.9 GeV （momentum transfer squared t range of -1.2 to -0.25 GeV2） and 1.9 to 2.1 CeV （t range of -1.4 to -0.25 GeV2） from the g8b experimental data collected in the summer of 2005 in the Hall B of Jefferson Lab.

关键词： photoproduction of Ф-mesons linearly-polarized photons polarization observables