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An Effective Configuration of Ensemble Size and Horizontal Resolution for the NCEP GEFS

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Advances in Atmospheric Sciences 2012年第4期29卷 782-794页

作者：麻巨慧 Yuejian ZHU richard WOBUS Panxing WANG Key laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science ＆ Technology Nanjing 210044 Environmental Modeling Center/NCEP/NOAA Camp Springs MD 20746 USA UCAR Boulder CO 80307 USA I.M. Systems Group Inc. （IMSG） at the Environmental Modeling Center/NCEP/NOAA Camp Springs MD 20746 USA

Two important questions are addressed in this paper using the Global Ensemble Forecast System （GEFS） from the National Centers for Environmental Prediction （NCEP）：（1） How many ensemble members are needed to better represent forecast uncertainties with limited computational resources？（2） What is tile relative impact on forecast skill of increasing model resolution and ensemble size？ Two-month experiments at T126l28 resolution were used to test the impact of varying the ensemble size from 5 to 80 members at the 500- hPa geopotential height. Results indicate that increasing the ensemble size leads to significant improvements in the performance for all forecast ranges when measured by probabilistic metrics, but these improvements are not significant beyond 20 members for long forecast ranges when measured by deterministic metrics. An ensemble of 20 to 30 members is the most effective configuration of ensemble sizes by quantifying the tradeoff between ensemble performance and the cost of computational resources. Two representative configurations of the GEFS the T126l28 model with 70 members and the T190l28 model with 20 members, which have equivalent computing costs--were compared. Results confirm that, for the NCEP GEFS, increasing the model resolution is more （less） beneficial than increasing the ensemble size for a short （long） forecast range.

关键词： NCEP operational GEFS ensemble size horizontal resolution ensemble mean tbrecast probabilistic forecast

Phonon imaging in 3D with a fibre probe

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light(Science & Applications) 2021年第6期10卷 1007-1019页

作者： Salvatore la Cavera III Fernando Perez-Cota richard JSmith Matt Clark Optics and Photonics Group Faculty of EngineeringUniversity of NottinghamUniversity ParkNottingham NG72RDUK

We show for the first time that a single ultrasonic imaging fibre is capable of simultaneously accessing 3D spatial information and mechanical properties from microscopic *** novel measurement system consists of two ultrafast lasers that excite and detect high-frequency ultrasound from a nano-transducer that was fabricated onto the tip of a single-mode optical fibre.A signal processing technique was also developed to extract nanometric in-depth spatial measurements from GHz frequency acoustic waves,while still allowing Brillouin spectroscopy in the frequency ***-free and non-contact imaging performance was demonstrated on various polymer *** singular device is equipped with optical lateral resolution,2.5μm,and a depth-profiling precision of 45 nm provided by *** endoscopic potential for this device is exhibited by extrapolating the single fibre to tens of thousands of fibres in an imaging *** a device catalyses future phonon endomicroscopy technology that brings the prospect of label-free in vivo histology within reach.

关键词： fibre equipped acoustics

Potential use of cucumber (Cucumis sativus l.) endophytic fungi as seed treatment agents against root-knot nematode Meloidogyne incognita

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第3期12卷 219-225页

作者： Xiao-ning YAN richard A. SIKORA Jing-wu ZHENG Institute of Biotechnology College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Soil-Ecosystem Phytopathology and Nematology Institute for Resource Conservation and Plant Science (INRES) Department of Plant Health University of Bonn Bonn 53115 Germany Institute of Environment and Plant Protection Chinese Academy of Tropical Agricultural Sciences Danzhou 5 7173 7 China

Seed treatment with endophytic fungi has been regarded as an effective method for plant parasitic nematode *** fungi from cucumber seedlings were isolated and screened for their potential to be used as seed treatment agents against Meloidogyne *** the 294 isolates screened,23 significantly reduced galls formed by *** in greenhouse *** 10 most effective isolates were Fusarium(5),Trichoderma(1),Chaetomium(1),Acremonium(1),Paecilomyces(1),and Phyllosticta(1) .Their control efficacies were repeatedly tested and their colonizations as well as in vitro activity against *** were *** reduced the number of galls by 24.0%-58.4%in the first screening and 15.6%-44.3%in the repeated test,*** Ph511 and Chaetomium Ch1001 had high colonizations on both the roots and the aboveground parts of cucumber *** isolates had colonization preference on the roots,their root colonizations ranging from 20.1%to 47.3%of the total root *** Tr882,Paecilomyces Pa972,and Acremonium Ac985 had low colonizations on both the roots and the aboveground *** Ac985,Chaetomium Ch1001,Paecilomyces Pa972,and Phyllosticta Ph511 produced compounds affecting motility of the second stage juveniles of *** on these results,Chae-tomium Ch1001 was considered to have the highest potential as a seed treatment agent for *** biocontrol.

关键词： Cucumber endophytic fungi Meloidogyne incognita Control efficacy Colonization In vitro activity

International Gold Award lecture of COS:Using evidence-based clinical practice guidelines to improve patient care:A global initiative

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International Gold Award Lecture of COS:Using evidence-based...

Trade-off between microbial carbon use efficiency and specific nutrient-acquiring extracellular enzyme activities under reduced oxygen

中华医学会第十二届全国眼科学术大会

作者： richard l.Abbott Intemational Council of Ophthalmology

Clinical Practice Guidelines (PPPs) were introduced into China one year ago at the Annual Congress in *** challenge facing the Chinese Ophthalmologic Society (COS) is now to widely disseminate these Guidelines to Opht...

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Soil Ecology letters 2023年第2期5卷 43-53页

作者： Ji Chen Irene Cordero Daryl l.Moorhead Jennifer K.Rowntree lorae T.Simpson richard D.Bardgett Hayley Craig Department of Agroecology Aarhus University8830 TjeleDenmark Aarhus University Centre for Circular Bioeconomy Aarhus University8830 TjeleDenmark iClIMATE Interdisciplinary Centre for Climate Change Aarhus University4000 RoskildeDenmark Department of Earth and Environmental Sciences The University of ManchesterOxford RoadManchesterM139PTUK Department of Environmental Sciences University of Toledo2801 W.Bancroft St.ToledoOH 43606-3390USA School of Biological and Marine Sciences University of PlymouthDrake CircusPlymouthPL48AAUK Florida Oceanographic Society 890 NE Ocean BlvdStuartFL 34996USA NatureMetrics Occam CourtSurrey Research ParkGuildfordGU27HJUK

Mangroves are one of the most ecologically sensitive ecosystems to global climate change,which have cascading impacts on soil carbon(C),nitrogen(N)and phosphorus(P)***,mangroves are experiencing increasing N and P loadings and reduced oxygen availability due to intensified climate change and human ***,both direct and interactive effects of these perturbations on microbially mediated soil C,N and P cycling are poorly ***,we simultaneously investigated the effects of N and P loadings and reduced oxygen on microbial biomass,microbial respiration,and extracellular enzyme activities(EEAs)in mangrove *** calculated the microbial metabolic quotient(qCO_(2)),which is regarded as a useful inverse metric of microbial C use efficiency(CUE).Our results show that reduced oxygen significantly increases both qCO_(2) and microbial specific EEAs(enzyme activity per unit of microbial biomass)for C-,N-and P-acquisition regardless of N or P ***,we found that qCO_(2) positively correlated with microbial specific EEAs under reduced oxygen,whereas no clear relationship was detected under ambient *** results suggest that reduced oxygen increases microbial specific EEAs at the expense of increasing microbial respiration per unit biomass,indicating higher energy cost per unit enzyme production.

关键词： reduced oxygen extracellular enzyme microbial respiration nutrient acquisition nutrient addition mangrove

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茶园防霜机不同时间尺度作用效果研究

农业机械学报 2013年第12期44卷 252-257页

作者：胡永光朱霄岚赵梦龙 richard l Snyder 李萍萍江苏大学现代农业装备与技术教育部重点实验室镇江212013 加利福尼亚大学(戴维斯)农业与环境科学学院 davis95616 南京林业大学森林资源与环境学院南京210037

在发生晚霜的茶园中,试验研究了防霜机不同时间尺度启闭的防霜效果。在茶树萌芽前不同天数、降霜前和日出后不同时间,分别设定开始启用和启闭防霜机的处理,测定其对茶树生长、冠层温度和防霜范围的影响。结果表明:在茶树萌芽前20、15、... 详细信息

在发生晚霜的茶园中,试验研究了防霜机不同时间尺度启闭的防霜效果。在茶树萌芽前不同天数、降霜前和日出后不同时间,分别设定开始启用和启闭防霜机的处理,测定其对茶树生长、冠层温度和防霜范围的影响。结果表明:在茶树萌芽前20、15、7 d开始启用防霜机,使新梢长度、芽密度和百芽质量均比对照增加20%以上;防霜机在降霜前2.0、1.5、1.0 h启动,对茶树防霜效果更显著,作用半径比对照增大60%以上;防霜机在日出后2.0、1.5、1.0 h延停,在开始的1 h内可平均减缓冠层温升45.76%,并减小茶树叶片光合强度的降幅。所以,晚霜时为保持茶树较好的长势和产量,应在茶树萌芽前不少于7 d开始启用防霜机,且合适的启动和延停时机分别为降霜前1.0 h和日出后1.0 h。

关键词：防霜机时间尺度晚霜冻茶树防霜效果

Te-seeded growth of few-quintuple layer Bi2Te3 nanoplates

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Nano Research 2014年第9期7卷 1243-1253页

作者： Yanyuan Zhao Maria de la Mata richard l. J. Qiu Jun Zhang Xinglin wen Cesar Magen Xuan P. A. Gao Jordi Arbiol Qihua Xiong Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371 Institut de Ciencia de Materials de Barcelona ICMAB-CSIC E-08193 Bellaterra CAT Spain Department of Physics Case Western Reserve University Cleveland Ohio 44106 USA laboratorio de Microscopfas Avanzadas (lMA) Instituto de Nanociencia de Aragon (INA) - ARAID and Departamento de Fisica de la Materia Condensada Universidad de Zaragoza 50018 Zaragoza Spain Institucio Catalana de Recerca i Estudis Avancats (ICREA) 08010 Barcelona CAT Spain NOVITAS Nanoelectronics Centre of Excellence School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798

We report on a Te-seeded epitaxial growth of ultrathin Bi2Te3 nanoplates （down to three quintuple layers （Ql）） with large planar sizes （up to tens of micrometers） through vapor transport. Optical contrast has been systematically investigated for the as-grown Bi2Te3 nanoplates on the SiO2/Si substrates, experimentally and computationally. The high and distinct optical contrast provides a fast and convenient method for the thickness determination of few-Ql Bi2Te3 nanoplates. By aberration-corrected scanning transmission electron microscopy, a hexagonal crystalline structure has been identified for the Te seeds, which form naturally during the growth process and initiate an epitaxial growth of the rhombohedral- structured Bi2Te3 nanoplates. The epitaxial relationship between Te and Bi2T% is identified to be perfect along both in-plane and out-of-plane directions of the layered nanoplate. Similar growth mechanism might be expected for other bismuth chalcogenide layered materials.

关键词： Te nucleation seed epitaxial growth Bi2Te3 few-quintuple layer TEM cross-section optical contrast

Comparison of Venusian Coronae with Giant Circumferential Dyke Swarms on Earth

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 183-184页

作者： Erin M.BETHEll richard E.ERNST Claire SAMSON Kenneth l.BUCHAN Department of Earth Sciences Carleton University Faculty of Geology and Geography Tomsk State University Geological Survey of Canada

The surface of Venus features a large number(>500)of quasi-circular tectono-magmatic features known as *** are characterized in part by their topographic characteristics,which can be diverse and

关键词： Comparison of Venusian Coronae with Giant Circumferential Dyke Swarms on Earth

Initial Field Evaluation of the Agro-Economic Effects of Determining Nitrogen Fertilizer Rates with a Recently-Developed Soil Test Methodology

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Open Journal of Soil Science 2013年第2期3卷 91-99页

作者： R. Daren Harmel richard l. Haney Grassland Soil and Water Research Laboratory USDA-Agricultural Research Service (ARS) Temple Texas USA.

Although agriculture is not the only contributor of excess nutrients to US waters, agriculture is an important contributor and should do its part to reduce nutrient loading. One important step in reducing agricultural contribution is to accurately account for all sources of plant available nutrients so that only needed nutrients are applied. In this study, three fertilizer rate treatments were evaluated: no fertilizer (control), traditional rate, and reduced rate based on a recently-developed enhanced soil test methodology. For each of nine sites in Texas, fertilizer data (formulation, rate, cost, and application date) and crop data (yield, price, and harvest date) were recorded, and economic throughput (profit) was determined. In this four year study, fertilizer rates were reduced 30%-50% (and fertilizer costs reduced 23%-39%) based on enhanced soil test methodology recommendations for wheat, corn, oats, and grain sorghum, but yields were not significantly reduced (0%-6%) and oat yields actually increased 5%. Profit decreased -18% for wheat, oats, and grain sorghum with reduced fertilizer rates. Although these changes were not statistically significant, they do represent benefit through increased profit potential and decreased input cost and production risk. In only 6% of the time was the traditional fertilizer rate the most profitable, compared to 51% for the unfertilized treatment and 43% for the enhanced soil test treatment. These results do not indicate that fertilizer application should be avoided but that fertilizer rates should be carefully chosen considering all sources of plant available nutrients (e.g., mineralization, irrigation water, nutrients deeper in the soil profile) to ensure that fertilizer is applied at the optimal rate.

关键词： Soil Tests Crop Yields On-Farm Profit Water Quality