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Programmable microfluidic genotyping of plant DNA samples for marker-assisted selection

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Microsystems & Nanoengineering 2018年第1期4卷 413-422页

作者： Helena C.Zec Tony Zheng Lingshu Liu Kuangwen Hsieh Tushar D.Rane Todd Pederson Tza-Huei Wang Department of Biomedical Engineering Johns Hopkins UniversityBaltimoreMD 21218USA Department of Mechanical Engineering Johns Hopkins UniversityBaltimoreMD 21218USA Pioneer Hi-Bred international inc. JohnstonIA 50131USA

As demands to maintain the global food production continue to mount,multinational seed companies are turning to new DNA marker technologies to accelerate the rate of plant breeding and crop *** key to widespread adoption of molecular breeding is the availability of flexible and cost-effective tools that can perform combinatorial and high-throughput genotyping of single-nucleotide polymorphisms(SNPs)to guide the crop development *** this end,we have developed a programmable,droplet-based microfluidic device for genotyping maize genomic DNA.A unique feature of the microfluidic platform is the nano sample processors(NSPs),which allow the device to sequentially load an unrestricted number of unique DNA samples using only two inlets,overcoming the current limitation to the number of sample inputs due to small device *** and programmable droplet generation within the device allows each sample to be genotyped against a panel of markers on ***,we have successfully implemented the Invader assay for SNP genotyping in flowing,50-nL droplets,thus achieving significant reduction in consumption of reagents per reaction as compared with conventional genotyping *** a demonstration,we performed 240 Invader reactions(testing 8 DNA samples against 10 SNP markers)and achieved greater than 93% accuracy in SNP calling of plant DNA samples in a single droplet-based experiment.

关键词： droplets genotyping invader assay microfluidics single-nucleotide polymorphism

Behavioral responses for evaluating the attractiveness of specific tea shoot volatiles to the tea green leafhopper, Empoaca vitis

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Insect Science 2012年第2期19卷 229-238页

作者： Dan Mu Lin Cui Jian Ge Meng-Xin Wang Li-Fang Liu Xiao-Ping Yu Qing-He Zhang Bao-Yu Han Tea Research Institute of Chinese Academy of Agricuitural Sciences Zhejiang Provinc.al Key Laboratory of Biometrology and Inspection&Quarantine College of Life Sciences of China Jiliang UniversityHangzhouChina Sterling international Inc.SpokaneWAUSA

The tea green leafhopper, Empoasca vitis Gothe, is one of the most serious insect pests of tea plantations in China's Mainland. Over the past decades, this pest has been controlled mainly by spraying pesticides. Insecticide applications not only have become less effective in controlling damage, but even more seriously, have caused high levels of toxic residues in teas, which ultimately threatens human health. Therefore, we should seek a safer biological control approach. In the present study, key components of tea shoot volatiles were identified and behaviorally tested as potential leafhopper attractants. The following 13 volatile compounds were identified from aeration samples of tea shoots using gas chromatography-mass spectrometry （GC-MS）：（E）-2-hexenal, （Z）-3-hexen-1- ol, （Z）-3-hexenyl acetate, 2-ethyl-1-hexanol, （E）-ocimene, linalool, nonanol, （Z）-butanoic acid, 3-hexenyl ester, decanal, tetradecane, β-caryophyllene, geraniol and hexadecane. In Y-tube olfactometer tests, the following individual compounds were identified：（E）-2- hexenal, （E）-ocimene, （Z）-3-hexenyl acetate and linalool, as well as two synthetic mixtures （called blend 1 and blend 2） elicited significant taxis, with blend 2 being the most attractive. Blend 1 inc.uded linalool, （Z）-3-hexen-l-ol and （E）-2-hexenal at a 1： 1：1 ratio, whereas blend 2 was a mixture of eight compounds at the same loading ratio：（E）-2-hexenal, （Z）- 3-hexen-l-ol, （Z）-3-hexenyl acetate, 2-penten-l-ol, （E）-2-pentenal, pentanol, hexanol and 1-penten-3-ol. In tea fields, the bud-green sticky board traps baited with blend 2, （E）-2- hexenal or hexane captured adults and nymphs of the leafhoppers, with blend 2 being the most attractive, foUowed by （E）-2-hexenal and hexane. Placing sticky traps baited with blend 2 or （E）-2-hexenal in the tea fields significantly reduced leathopper populations. Our results indicate that the bud-green sticky traps baited with tea shoot volatiles can provide a new tool for monitoring and managing the

关键词： attractant behavior green leaf volatiles tea green leafhopper tea shoot volatiles

A Multi-Feature Weighting Based K-Means Algorithm for MOOC Learner Classification

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Computers, Materials & Continua 2019年第5期59卷 625-633页

作者： Yuqing Yang Dequn Zhou Xiaojiang Yang College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing211106China Office of international Cooperation and Exchanges Nanjing University of Finance&EconomicsNanjing210046China Jiangsu Guidgine Educational Evaluation inc. Nanjing210046China international Education Office of Centennial College TorontoP.O.Box 631Canada

Massive open online courses(MOOC)have recently gained worldwide attention in the field of *** manner of MOOC provides a new option for learning various kinds of knowledge.A mass of data miming algorithms have been proposed to analyze the learner’s characteristics and classify the learners into different ***,most current algorithms mainly focus on the final grade of the learners,which may result in an improper *** overcome the shortages of the existing algorithms,a novel multi-feature weighting based K-means(MFWK-means)algorithm is proposed in this *** between the widely used feature grade and other features are first investigated,and then the learners are classified based on their grades and weighted features with the proposed MFWK-means *** results with the Canvas Network Person-Course(CNPC)dataset demonstrate the effectiveness of our ***,a comparison between the new MFWK-means and the traditional K-means clustering algorithm is implemented to show the superiority of the proposed method.

关键词： Multi-feature weighting learner classification MOOC clustering

Geologic data collection and assessment techniques in coal mining for ground control

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international Journal of Mining Science and Technology 2020年第1期30卷 131-139页

作者： Mark Van Dyke Ted Klemetti Joe Wickline NIOSH Pittsburgh15236 PAUSA Coronado Global Resources inc. BeckleyWVUSA

The identification and mitigation of adverse geologic conditions are critical to the safety and productivity of underground coal mining *** anticipate and mitigate adverse geologic conditions,a formal method to evaluate geotechnical factors must be *** mine is unique and has its own separate approach for defining what an adverse geological condition consists *** collection of geologic data is a first critical step to creating a geological database to map these hazards efficiently and *** considerations must be taken into account,such as lithology of immediate roof and floor strata,seam height,gas and oil wells,faults,depressions in the mine floor(water)and inc.eases in floor elevation(gas),overburden,streams and horizontal stress directions,amongst many other *** geologic data is collected,it can be refined and integrated into a database that can be used to develop maps showing the trend,orientation,and extent of the adverse geological *** information,delivered in a timely manner,allows mining personnel to be proactive in mine planning and support implementations,ultimately reducing the impacts of these *** paper covers geologic exploratory methods,data organization,and the value of collecting and interpreting geologic information in coal mines to enhance safety and *** implementation of the methods described above has been proven effective in predicting and mitigating adverse geologic conditions in underground coal *** re-evaluation of data collection methods,geologic interpretations,mapping procedures,and communication techniques ensures continuous improvement in the accuracy of predictions and mitigation of adverse geologic *** a concise record of the work previously done to track geologic conditions at a mine will allow for the smoothest transition during employee turnover and *** refinements and standardization of data collection methods,

关键词： Roof control Database Mapping Hazards Geology

单晶镍基合金蠕变时γ′组织形态变化的计算机模拟

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金属热处理学报 2000年第2期21卷 42-45页

作者：冯华 Magna international inc.

运用有限元法及能量扰动法对单晶镍基合金蠕变过程显微组织的变化进行了动态模拟。模拟结果表明在外加拉或压应力下显微组织不同的变化过程。该变化对单晶镍基合金在蠕变经过一定时间后的点阵参数和点阵错配度有影响。

关键词：有限元单晶镍基合金蠕变计算机模拟 γ'相

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“人性化”在急诊中心设计中的体现

建筑学报 2005年第12期 70-72页

作者：袁晨悦 Heery InternationalInc.(美国)

亚特兰大医疗中心急诊中心设计以使用者为主导,充分考虑“人性化”,把各个使用空间从功能上有机地结合在一起,从而达到为使用者服务的目的。

关键词：急诊中心使用空间使用者人性化

Signal Detection and Risk Management

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Signal Detection and Risk Management

Plant Cell Wall Matrix Polysaccharide Biosynthesis

第十二次全国临床药理学学术会议

作者：李浩 HQ Safety international inc.

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Molecular Plant 2009年第5期2卷 840-850页

作者： Ajay Pal S. Sandhu Gursharn S. Randhawa Kanwarpal S. Dhugga Crop Genetics Research and Development Pioneer Hi-Bred International Inc. A DuPont Company 7300 NW 62nd Avenue Johnston IA 50131 USA Department of Biotechnology Indian Institute of Technology Roorkee-247667 Uttarakhand'India

The wall of an expanding plant cell consists primarily of cellulose microfibrils embedded in a matrix of hemicellulosic and pectic polysaccharides along with small amounts of structural and enzymatic proteins. Matrix polysaccharides are synthesized in the Golgi and exported to the cell wall by exocytosis, where they intercalate among cellulose microfibrils, which are made at the plasma membrane and directly deposited into the cell wall. Involvement of Golgi glucan synthesis in auxin-induced cell expansion has long been recognized; however, only recently have the genes corresponding to glucan synthases been identified. Biochemical purification was unsuccessful because of the labile nature and very low abundance of these enzymes. Mutational genetics also proved fruitless. Expression of candidate genes identified through gene expression profiling or comparative genomics in heterologous systems followed by functional characterization has been relatively successful. Several genes from the cellulose synthase-like （Csl） family have been found to be involved in the synthesis of various hemicellulosic glycans. The usefulness of this approach, however, is limited to those enzymes that probably do not form complexes consisting of unrelated proteins. Nonconventional approaches will continue to inc.ementally unravel the mechanisms of Golgi polysaccharide biosynthesis.

关键词： Biofuels cell wall Csl Golgi hemicellulose membrane biochemistry.

Fusion Reaction Rate Coefficient for Different Beam and Target Scenarios

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Chinese Physics Letters 2015年第2期32卷 43-47页

作者：欧巍曾宪俊邓柏权苟富均 Institute of Nuclear Science and Technology Sichuan University HOPE Innovations inc. Southwestern Institute of Physics

Fusion power output is proportional not only to the fuel particle number densities participating in reaction but also to the fusion reaction rate coefficient （or reactivity）, which is dependent on reactant velocity distribution functions. They are usuMly assumed to be dual Maxwellian distribution functions with the same temperature for thermal nuclear fusion circumstances. However, if high power neutral beam injection and minority ion species ICRF plasma heating, or multi-pinc.ed plasma beam head-on collision, in a converging region are required and investigated in future large scale fusion reactors, then the fractions of the injected energetic fast ion tail resulting from ionization or charge exchange will be large enough and their contribution to the non-Maxwellian distribution functions is not negligible, hence to the fusion reaction rate coefficient or calculation of fusion power. In such cases, beam-target, and beam-beam reaction enhancement effect contributions should play very important roles. In this paper, several useful formulae to calculate the fusion reaction rate coefticient for different beam and target combination scenarios are derived in detail

关键词： Fusion Reaction Rate Coefficient for Different Beam and Target Scenarios exp