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Asian Agricultural Research 2016年第6期8卷 51-53,56页

作者： Hua WANG Zizhen DUAN College of Humanities and Social Development Northwest A&F University

Most volunteer organizations in universities focus their attention on urban communities and residents,but neglect rural *** universities have responsibilities and conditions to serve rural areas,and should bring into play their leading role. This study surveyed situations of volunteers of northwest a&f university serving rural left-behind children,and found that there are problems including weak volunteer awareness,unstable organization members,imperfect organization construction,and lack of effect incentive mechanism. finally,it came up four recommendations: strengthening " active service" ideological education,improving management system construction,establishing incentive mechanism,and setting up brand project,to provide feasible path for agricultural universities serving rural weak groups in a better way.

关键词： Left-behind children Volunteer education support Long-term service

Protein sequence analysis based on hydropathy profile of amino acids

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Journal of Zhejiang university-Science B(Biomedicine & Biotechnology) 2012年第2期13卷 152-158页

作者： Xiao-li XIE Li-fei ZHENG Ying YU Li-ping LIANG Man-cai GUO John SONG Zhi-fa YUAN College of Sciences Northwest A&F UniversityYangling 712100China College of Animal Science and Technology Northwest A&F University Yangling 712100 China College of Animal Science and Technology China Agriculture UniversityBeijing 100193China Department of Animal and Avian Sciences University of MarylandCollege ParkMD 20742USA

Biology sequence comparison is a fundamental task in computational *** to the hydropathy profile of amino acids,a protein sequence is taken as a string with three *** curves of the new protein sequence were defined to describe the protein sequence.A new method to analyze the similarity/dissimilarity of protein sequence was proposed based on the conditional probability of the protein ***,the protein sequences of ND6(NADH dehydrogenase subunit 6)protein of eight species were taken as an example to illustrate the new *** results demonstrated that the method is convenient and efficient.

关键词： Protein sequence Sequence comparison Similarity/dissimilarity Conditional probability

Prevention and Intervention Measures for Abnormal Psychology of Rural College Students: A Case Study of northwest a&f university

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Asian Agricultural Research 2017年第5期9卷 92-95页

作者： Chunfang WU College of Marxism Northwest A&F University

Due to the negative influence of family's cultural and education level,economic development,and rural traditional culture,rural college students have such abnormal psychology as inferiority complex in learning and job selection,high psychological pressure,sensitive interpersonal relationship,high emotion fluctuation,confusion in love and sex,and high unknown risks. Therefore,through strengthening the effectiveness of abnormal psychological prevention and intervention,it is expected to prevent rural college students from becoming psychological weak.

关键词： Rural college students Abnormal psychology Measures

SSR markers development and their application in genetic diversity evaluation of garlic(Allium sativum)germplasm

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Plant Diversity 2022年第5期44卷 481-491页

作者： Xiaxia Li Lijun Qiao Birong Chen Yujie Zheng Chengchen Zhi Siyu Zhang Yupeng Pan Zhihui Cheng College of Horticulture Northwest A&F UniversityYangling712100Shaanxi ProvinceChina

Garlic(Allium sativum),an asexually propagated vegetable and medicinal crop,has abundant genetic *** diversity evaluation based on molecular markers has apparent advantages since their genomic abundance,environment insensitivity,and non-tissue specific ***,the limited number of available DNA markers,especially SSR markers,are insufficient to conduct related genetic diversity assessment studies in *** this study,4372 EST-SSR markers were newly developed,and 12 polymorphic markers together with other 17 garlic SSR markers were used to assess the genetic diversity and population structure of 127 garlic *** averaged polymorphism information content(PIC)of these 29 SSR markers was 0.36,ranging from 0.22 to ***-nine polymorphic loci were detected among these accessions,with an average of 3.48 polymorphic loci per *** the clustering analyses based on either the genotype data of SSR markers or the phenotypic data of morphological traits obtained genetic distance divided the 127 garlic accessions into three ***,the Mantel test showed that genetic distance had no significant correlations with geographic distance,and weak correlations were found between genetic distance and the phenotypic *** analysis showed that the main genetic variation of this garlic germplasm collection existed in the within-population or *** of this study will be of great value for the genetic/breeding studies in garlic and enhance the utilization of these garlic germplasms.

关键词： Garlic SSR markers Genetic diversity Population structure

Temperature measurement and analysis of postharvest agricultural products associated with thermal disinfestations

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International Journal of Agricultural and Biological Engineering 2013年第2期6卷 87-94页

作者： Yan Rongjun Huang Zhi Li Rui Zhu Hankun Ling Bo Shaojin Wang College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China Department of Biological Systems Engineering Washington State UniversityPullmanWA 99164-6120USA

Hot air and hot water treatments are practical,environmentally-friendly and non-chemical heating methods,which are widely used for postharvest insect control and quality preservation in agricultural *** apple and pear as representative fruits,this study mainly analyzed influences of their thermal properties,diameter,and medium speed on the heating rates of fruits through their real-time measured temperatures at surface and *** on the reported thermal death kinetic models of the target codling moth,the minimum heating time was estimated to achieve 100%insect *** results showed that the heating rates in fruits decreased gradually with the increasing depth from the surface to the *** increasing heating time,the heating rate became *** apple was heated faster than the *** water was more effective than hot air in treating *** hot air speed increased the heating rate but increasing water circulating speed had no clear effects on the heating *** on the measured temperature-time history of the fruit center,the minimum heating time could be effectively determined for codling moth control through the estimated total equivalent thermal lethal *** results could provide reliable validation data for the computer simulation and a scientific basis to improve the hot air and hot water treatments.

关键词： hot air hot water fruit postharvest treatment heating rates temperature measurement thermal disinfestation

Methods to detect a vian influenza virus for food safety surveillance

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Journal of Integrative Agriculture 2015年第11期14卷 2296-2308页

作者： SHI Ping Shu Geng LI Ting-ting LI Yu-shui fENG Ting WU Hua-nan School of Environment and Energy Peking University Shenzhen Graduate School Sino-US Joint food Safety Research Center Northwest A&F University Department of Plant Science University of California

Avian influenza （AI）, caused by the influenza A virus, has been a global concern for public health. AI outbreaks not only impact the poultry production, but also give rise to a risk in food safety caused by viral contamination of poultry products in the food supply chain. Distinctions in AI outbreak between strains H5N1 and H7N9 indicate that early detection of the AI virus in poultry is crucial for the effective warning and control of AI to ensure food safety. Therefore, the establishment of a poultry surveillance system for food safety by early detection is urgent and critical. In this article, methods to detect AI virus, including current methods recommended by the World Health Organization （WHO） and the World Organisation for Animal Health （Office International des Epizooties, OIE） and novel techniques not commonly used or commercialized are reviewed and evaluated for feasibility of use in the poultry surveillance system. Conventional methods usually applied for the purpose of AI diagnosis face some practical challenges to establishing a comprehensive poultry surveillance program in the poultry supply chain. Diverse development of new technologies can meet the specific requirements of AI virus detection in various stages or scenarios throughout the poultry supply chain where onsite, rapid and ultrasensitive methods are emphasized. Systematic approaches or integrated methods ought to be employed according to the application scenarios at every stage of the poultry supply chain to prevent AI outbreaks.

关键词： avian influenza food safety detection methods poultry supply chain surveillance system

Wolfberry tree dual-model detection method and orchard target-oriented fertilization system based on photoelectric sensors

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 65-73页

作者： Shuo Yang Changyuan Zhai John Long Bo Zhang Hanzhe Li College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYanglingShaanxi 712100China Department of Biosystems and Agricultural Engineering Oklahoma State UniversityStillwaterOK 74078USA

Orchard target-oriented fertilizing with on-board sensor technology can improve fertilizer efficiency and reduce environmental *** sensors are widely used for object detection because of their low cost and fast response *** paper presents a Wolfberry tree dual-model detection method and the design of an orchard target-oriented variable-rate fertilization system based on photoelectric *** dual-model detection method includes the Trunk Detection Model(TDM)and Canopy Detection Model(CDM),which can be applied for Wolfberry orchards at the green cluster and mature stages,respectively.A target-oriented fertilization system was designed using the dual-model method,and tested in the lab and Chinese Wolfberry *** laboratory test results showed that the average center offset distances on the condition of detecting trunks,continuous canopies,and discontinuous canopies were 4.1 cm,9.1 cm and 13.1 cm,*** system could ignore the signals from canes when their diameters were less than 16 mm,and also could determine the gaps within a tree when they were less than 21 *** orchard test results showed that the system accomplished target-oriented fertilization 95 times for 92 trees at the mature *** results indicated that the dual-model detection method could be used for Wolfberry trees or other trees with similar canopy changes at different growth stages.

关键词： orchard fertilizer target-oriented fertilization variable rate fertilization photoelectric sensor wolfberry orchard

Nonlinear fast–slow dynamics of a coupled fractional order hydropower generation system

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Chinese Physics B 2018年第12期27卷 538-545页

作者： Xiang Gao Diyi Chen Hao Zhang Beibei Xu Xiangyu Wang Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas Ministry of EducationNorthwest A & F University Institute of Water Resources and Hydropower Research Northwest A & F University Australasian Joint Research Centre for Building Information Modelling School of Built Environment Curtin University

Internal effects of the dynamic behaviors and nonlinear characteristics of a coupled fractional order hydropower generation system(HGS) are analyzed. A mathematical model of hydro-turbine governing system(HTGS) with rigid water hammer and hydro-turbine generator unit(HTGU) with fractional order damping forces are proposed. Based on Lagrange equations, a coupled fractional order HGS is established. Considering the dynamic transfer coefficient eis variational during the operation, introduced e as a periodic excitation into the HGS. The internal relationship of the dynamic behaviors between HTGS and HTGU is analyzed under different parameter values and fractional order. The results show obvious fast–slow dynamic behaviors in the HGS, causing corresponding vibration of the system, and some remarkable evolution phenomena take place with the changing of the periodic excitation parameter values.

关键词： fast–slow dynamics fractional order nonlinear dynamics hydropower generation system

Response of axillary bud development in garlic(Allium sativum L.) to seed cloves soaked in gibberellic acid(GA3) solution

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Journal of Integrative Agriculture 2020年第4期19卷 1044-1054页

作者： LIU Hong-jiu HUANG Cai-ping TONG Pei-jiang YANG Xue CUI Ming-ming CHENG Zhi-hui College of Horticulture Northwest A&F UniversityYangling 712100P.R.China College of Plant Protection Northwest A&F UniversityYangling 712100P.R.China

Gibberellins(GAs) are important phytohormones that regulate many developmental processes in plants. Clove, as the reproductive organ of garlic, dramatically affected garlic bulb development. Considering the potential of gibberellins in plant development and our previous studies, we investigated the effect of soaking two types of seed cloves(seed clove-I: without root/shoot sprouting;seed clove-II: with root/shoot sprouting) in GA3 solution on axillary bud development and examined the effect of soaking seed cloves in GA3 solution on bulb development, phytohormone level and sugar content in this *** indicated seed clove types, soaking liquids and their interaction significantly affected the number of cloves per bulb and the rate of single-clove bulb. Moreover, soaking seed cloves in 1 mmol L^-1 GA3 solution for 24 h not only promoted axillary bud formation and secondary plant growth(equal to tillering or branching), but also slightly increased the number of cloves per bulb and changed bulb structure with a low yield and marketable quality. On the 40 th day after GA3 treatment(at axillary bud outgrowth stage), zeatin riboside(ZR) and soluble protein in stem were sharply increased with the increase of GA3, sucrose, fructose and soluble protein in leaf. However, GA3, indole-3-acetic acid(IAA), soluble sugar and sucrose in stem(3.52 ng g^-1 fresh weight(fW), 19.88 ng g^-1 fW, 237.3 mg g^-1 fW, and 8.24 mg g^-1 fW, respectively) were significantly decreased on the 40 th day after GA3 treatment, compared to the control of water treatment(5.56 ng g^-1 fW, 32.96 ng g^-1 fW, 263.6 mg g^-1 fW, and 10.37 mg g^-1 fW, respectively). To our knowledge, these novel results indicate seed cloves soaked in GA3 solution promotes axillary bud formation and outgrowth that caused the changes in plant architecture and bulb structure. Meanwhile, our findings suggest that the level of endogenous plant hormone(GA3, IAA and ZR) cooperates with the content of sugar(sucrose and fructose)

关键词： garlic(Allium sativum) gibberellic acid seed clove axillary bud plant hormone sugar

Trends of Yield and Soil fertility in a Long-Term Wheat-Maize System

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Journal of Integrative Agriculture 2014年第2期13卷 402-414页

作者： YANG Xue-yun SUN Ben-hua ZHANG Shu-lan State Key Laboratory of Soil Erosion and Dryland farming Northwest A&F University Key Laboratory of Plant Nutrition and the Agri-Environment in northwest China Ministry of Agriculture/Northwest A&F University

The sustainability of the wheat-maize rotation is important to China＇s food security. Intensive cropping without recycling crop residues or other organic inputs results in the loss of soil organic matter （SOM） and nutrients, and is assumed to be non- sustainable. We evaluated the effects of nine different treatments on yields, nitrogen use efficiency, P and K balances, and soil fertility in a wheat-maize rotation system （1991-2010） on silt clay loam in Shaanxi, China. The treatments involved the application of recommended dose of nitrogen （N）, nitrogen and phosphorus （NP）, nitrogen and potassium （NK）, phosphorus and potassium （PK）, combined NPK, wheat or maize straw （S） with NPK （SNPK）, or dairy manure （M） with NPK （M1NPK and M2NPK）, along with an un-treated control treatment （CK）. The mean yields of wheat and maize ranged from 992 and 2 235 kg ha-1 under CK to 5 962 and 6 894 kg ha-1 under M2NPK treatment, respectively. Treatments in which either N or P was omitted （N, NK and PK） gave significantly lower crop yields than those in which both were applied. The crop yields obtained under NP, NPK and SNPK treatments were statistically identical, as were those obtained under SNPK and MNPK. However, M2NPK gave a significant higher wheat yield than NP, and MNPK gave significant higher maize yield than both NP and NPK. Wheat yields increased significantly （by 86 to 155 kg ha-1 yr-1） in treatments where NP was applied, but maize yields did not. In general, the nitrogen use efficiency of wheat was the highest under the NP and NPK treatments; for maize, it was the highest under MNPK treatment. The P balance was highly positive under MNPK treatment, increasing by 136 to 213 kg ha-1 annually. While the K balance was negative in most treatments, ranging from 31 to 217 kg ha^-1 yr^-1, levels of soil available K remained unchanged or increased over the 20 yr. SOM levels increased significantly in all treatments. Overall, the results indicated that combinations of organic manure an

关键词： wheat maize nitrogen use efficiency P balance K balance soil organic matter