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A double-layer model for improving the estimation of wheat canopy nitrogen content from unmanned aerial vehicle multispectral imagery

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Journal of Integrative Agriculture 2023年第7期22卷 2248-2270页

作者： LIAO Zhen-qi DAI Yu-long WAnG Han Quirine M.KETTERInGS LU Jun-sheng ZHAnG Fu-cang LI Zhi-jun FAn Jun-liang Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of the Ministry of Education Northwest A&F UniversityYangling 712100P.R.China department of animal Science Cornell UniversityIthacaNY 14853USA

The accurate and rapid estimation of canopy nitrogen content(CnC)in crops is the key to optimizing in-season nitrogen fertilizer application in precision ***,the determination of CnC from field sampling data for leaf area index(LAI),canopy photosynthetic pigments(CPP;including chlorophyll a,chlorophyll b and carotenoids)and leaf nitrogen concentration(LnC)can be time-consuming and *** we evaluated the use of high-precision unmanned aerial vehicle(UAV)multispectral imagery for estimating the LAI,CPP and CnC of winter wheat over the whole growth period.A total of 23 spectral features(SFs;five original spectrum bands,17 vegetation indices and the gray scale of the RGB image)and eight texture features(TFs;contrast,entropy,variance,mean,homogeneity,dissimilarity,second moment,and correlation)were selected as inputs for the *** machine learning methods,i.e.,multiple stepwise regression(MSR),support vector regression(SVR),gradient boosting decision tree(GBDT),Gaussian process regression(GPR),back propagation neural network(BPnn)and radial basis function neural network(RBFnn),were compared for the retrieval of winter wheat LAI,CPP and CnC values,and a double-layer model was proposed for estimating CnC based on LAI and *** results showed that the inversion of winter wheat LAI,CPP and CnC by the combination of SFs+TFs greatly improved the estimation accuracy compared with that by using only the *** RBFnn and BPnn models outperformed the other machine learning models in estimating winter wheat LAI,CPP and *** proposed double-layer models(R^(2)=0.67-0.89,RMSE=13.63-23.71 mg g^(-1),MAE=10.75-17.59 mg g^(-1))performed better than the direct inversion models(R^(2)=0.61-0.80,RMSE=18.01-25.12 mg g^(-1),MAE=12.96-18.88 mg g^(-1))in estimating winter wheat *** best winter wheat CnC accuracy was obtained by the double-layer RBFnn model with SFs+TFs as inputs(R^(2)=0.89,RMSE=13.63 mg g^(-1),MAE=10.75 mg g^(-1)).The results of this study can

关键词： UAV multispectral imagery spectral features texture features canopy photosynthetic pigment content canopy nitrogen content

LRRK2 regulates actin assembly for spindle migration and mitochondrial function in mouse oocyte meiosis

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Journal of Molecular Cell Biology 2022年第1期14卷 21-31页

作者： Zhen-nan Pan Jing-Cai Liu Jia-Qian Ju Yue Wang Shao-Chen Sun College of animal Science and Technology Nanjing Agricultural UniversityNanjing 210095China

Leucine-rich-repeat kinase 2 (LRRK2) belongs to the Roco GTPase family and is a large multidomain protein harboring both GTPase and kinase activities. LRRK2 plays indispensable roles in many processes, such as autophagy and vesicle trafficking in mitosis. In this study, we showed the critical roles of LRRK2 in mammalian oocyte meiosis. LRRK2 is mainly accumulated at the meiotic spindle periphery during oocyte maturation. depleting LRRK2 led to the polar body extrusion defects and also induced large polar bodies in mouse oocytes. Mass spectrometry analysis and co-immunoprecipitation results showed that LRRK2 was associated with several actin-regulating factors, such as Fascin and Rho-kinase (ROCK), and depletion of LRRK2 affected the expression of ROCK, phosphorylated cofilin, and Fascin. Further analysis showed that LRRK2 depletion did not affect spindle organization but caused the failure of spindle migration, which was largely due to the decrease of cytoplasmic actin filaments. Moreover, LRRK2 showed a similar localization pattern to mitochondria, and LRRK2 was associated with several mitochondria-related proteins. Indeed, mitochondrial distribution and function were both disrupted in LRRK2-depleted oocytes. In summary, our results indicated the critical roles of LRRK2 in actin assembly for spindle migration and mitochondrial function in mouse oocyte meiosis.

关键词： actin spindle LRRK2 oocyte meiosis

Assessment of commercial feedlot finishing practices at eastern Shoa, Ethiopia

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Open Journal of animal Sciences 2013年第4期3卷 273-280页

作者： Tsegay Teklebrhan Mengistu Urge College of Agriculture School of Animal and Range Sciences Haramaya University Dire Dawa Ethiopia College of Agriculture School of Animal and Range Sciences Haramaya University Dire Dawa Ethiopia

This study was conducted to characterize and identify husbandry practice and major constraints of commercial feedlot industries in the study area. Forty eight commercial feedlot farms were used to collect data. Data were analyzed using Statistical Package for the Social Sciences (SPSS). The results showed that, livestock species such as cattle, shoat and camels were used in commercial fattening though significant variation in demand among species. Cattle had got the highest acceptance in feedlot industries followed by shoat, however, camel and swine had least preference. All cattle breeds were granted equal requirement by domestic market. However, there is variation in demand among cattle breeds for export market. Boran was the most preferred cattle breed compared to the rest of cattle by the importers. Uncastrated bull demanded for export market however, castrated and female cattle were not used for export markets. Pastoralists were the potential supplier of feeder livestock followed by small holders to feedlot industries. Teff straw was predominantly used roughage feed in most of commercial feedlot farms and agro-industrial by-products as a source of concentrate. However, sorghum and maize grains were utilized by very few farms. Vitamin and mineral supplementation were not often available except common salt in all feedlot rations. Market was noted as the most potential constraints followed by feed and type of livestock coming to the markets in the commercial feedlot industries. The study suggested that, government and other development partners should provide and improve all services to pastoralists or producers in an organized way at their localities to ensure sustainable supply of livestock to the market.

关键词： Constraints Fattening Livestock

Evolution of gp85 gene of subgroup J avian leukosis virus under the selective pressure of antibodies

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Science China(Life Sciences) 2006年第3期49卷 227-234页

作者： WAnG Zhengfu CUI Zhizhong College of animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China

Subgroup J Avian leucosis virus (ALV-J) strain nX0101 was inoculated into chicken embryo fibroblasts (CEF) monolayers in 6-well plates. The six wells of CEF inoculated with nX0101 were divided into groups A (without anti-ALV-J serum in the medium); B (with anti-ALV-J serum in the medium), then viruses from each well of both groups were separately passed in CEF every 6 d; formed their independent passage lineages. For each lineage of both groups, gp85 genes of the viruses in the 10th, 20th; 30th passages were amplified, cloned; sequenced. The sequence data indicated that the homologies of gp85 at aa level between the primary virus; the passed viruses of different passages of 3 lineages in group A were 97.7%–99.7%;; the homologies of gp85 between the primary virus; the passed viruses of different passages of 3 lineages in group B were 93.8%–96.1%. Analysis of the ratios of nonsynonium (nS) vs synonium (S) mutations of nucleic acids demonstrated that nS/S in 3 highly variable (hr-) regions at aa#110–120, aa#141–151; aa#189–194 of gp85 in 3 lineages of group A were 2 (8/4), 1(3/3); 1.3 (4/3), however, nS/S in the same 3 hr-regions of group B were 4.1 (13/3), 4.7 (14/3); 3.3 (11/3). This study is the first demonstration of influence of immune selective pressure on evolution of ALV-J gp85 by specific antibodies under the controlled in vitro experiments.

关键词： subgroup J avian leucosis virus, gp85 gene, evolution, immune selection.

Report on a breeding objective that may reduce the carbon footprint of extensive cow-calf production systems

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natural Science 2013年第1期5卷 167-171页

作者： Motshabi Catherine Mokolobate Machiel Matthys Scholtz Sendros demeke Mulugeta Frederick Wilhelm Cornelius neser ARC-animal Production Institute Irene South Africa&Department of Animal Wildlife and Grassland Sciences University of Free State Bloemfontein South Africa ARC-animal Production Institute Irene South Africa *Corresponding Author department of animal Wildlife and Grassland Sciences University of Free State Bloemfontein South Africa north West University Mmabatho South Africa

Most measurements for beef improvement in South Africa are per individual (weaning weight, calving interval, growth rate, etc.). A measurement that expresses performance per constant unit, e.g. kilogram calf weaned per Large Stock Unit (LSU) can eventually be translated to kilogram calf produced per kg CO2 equivalent. A LSU is defined as a bovine requiring 75 MJ Metabolisable Energy (ME) per day. If more kilogram weaner calf can be produced per LSU (KgC/LSU), the carbon footprint of beef can be reduced. This study used breed average values to investigate the KgC/LSU for the 30 beef and dual purpose breeds in South Africa. The breeds were categorized in the following breed types: Sanga (indigenous to South Africa) Sanga derived, Zebu, Zebu derived, British and European. no relationship was found between cow weights and KgC/LSU, indicating that it is independent of cow weight between breeds. However, when the data is summarized into breed types, the Sanga and European breed types produce the least KgC/ LSU and Sanga derived breed types the most. This high value of the Sanga derived breeds is probably due to retained heterosis. Composite breeds are mostly intermediate to parental breeds for individual traits but superior for composite traits and KgC/LSU is a composite trait. These calculations were only done on breed averages. A genetic analysis on a breed level to estimate genetic parameters for this trait, and its genetic correlations with other traits now needs to be done before a decision can be taken whether selection for KgC/LSU will be feasible. The ultimate aim with a trait like this is to reduce the carbon footprint of weaner calf production since more kilogram calf will be produced per LSU (constant feed unit).

关键词： Beef Production Breeding Cattle Large Stock Unit Sanga Weaner Calf Component

Characterization of toxin from Verocytotoxigenic Ecscherichia coli(VTEC) strains isolated from neonatal calves in India

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Asian Pacific Journal of Tropical Medicine 2009年第2期2卷 35-38页

作者： Diganta Pan Ashok Kumar Bhatia Bhilegaonkar Kn department of Microbiology and Immunology College of Veterinary Science and Animal HusbandryMathura-281001UP(India) Indian Veterinary Research Institute IzatnagarU.P.243122India

Objective:The present study has characterized dialyzed toxin from non-0157 VTEC *** isolates by vero cell toxicity assay and pathogenecity in mice ***:Toxins from non-0157 verocytotoxic Escherichia coli isolated from neonatal calves were *** toxin from *** 026,0111 and 0103 serotypes were prepared and characterized by verocell toxicity assay and pathogenicity in mice *** 0157:H7 considered as positive control for this ***:Cytopathic effects in vero cell line first rounding of vero cells,followed by clumping of cells and finally disintegrated,blackened,shriveled cell line within 16 to 72 *** markers such as hind limb paralysis and reddening of tail were prominent in all the toxicated *** histopathological study was conducted for multiple organ ***: Several methods for toxin assay were developed based on biological,immunological and detection of virulence genes related to toxin production but each test has draw ***,it is likely that future effort will be focused on the development of assay,which is fast,reliable,specific and sensitive methods based on mice model.

关键词： Escherichia coli non-O157 verocytotoxic Escherichia coli Verocell cytotoxicity assay Mice lethality test

MHC II DRB variation and trans-species polymorphism in the golden snub-nosed monkey(Rhinopithecus roxellana)

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Chinese Science Bulletin 2013年第17期58卷 2119-2127页

作者： LUO MaoFang PAn HuiJuan College of nature Conservation Beijing Forestry University Key Laboratory of animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of Sciences Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Genetic variation is generally believed to be important in studying endangered species' adaptive *** studies assessed genetic diversity using nearly neutral markers,such as microsatellite loci and mitochondrial DnA(mtDnA),which are very informative for phylogenetic and phylogeographic ***,the variation at these loci cannot provide direct information on selective processes involving the interaction of individuals with their environment,or on the capability to resist continuously evolving pathogens and *** importance of genetic diversity at informative adaptive markers,such as major histocompatibility complex(MHC) genes,is increasingly being realized,especially in endangered,isolated *** population size and isolation make the golden snub-nosed monkey(Rhinopithecus roxellana) particularly susceptible to genetic variation losses through inbreeding and restricted gene *** this study,we compared the genetic variation and population structure of microsatellites,mtDnA,and the most relevant adaptive region of the MHC II-DRB genes in the golden snub-nosed *** examined three Chinese *** populations and found the same variation patterns in all gene regions,with the population from Shennongjia population,Hubei Province,showing the lowest polymorphism among three *** drift that outweighed balancing selection and the founder effect in these populations may explain the similar genetic variation pattern found in these neutral and adaptive genes.

关键词：川金丝猴濒危物种 MHCⅡ 多态性金色主要组织相容性复合体 DRB 线粒体DnA

Potential of edible insects as source of functional foods:biotechnological approaches for improving functionality

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Systems Microbiology and Biomanufacturing 2022年第3期2卷 461-472页

作者： Wahengbam deepanita devi Rajkumari Bonysana Kokho Kapesa Amit Kumar Rai Pulok Kumar Mukherjee Yallappa Rajashekar Insect Bioresources Laboratory Animal Resources ProgrammeInstitute Bioresources and Sustainable Development(IBSD)Takyelpat Imphal WestManipur 795001India Institute of Bioresources and Sustainable development Mizoram NodeAizwalMizoram 796001India

Consumption of insects as food has a long history and has been documented by many ***,it is extensively practiced in Africa,Asia,Australia,and Latin America as traditional food providing nutritional,economic and ecological benefit for rural *** today’s world,edible insects are limelight by many researchers and industrialist due to the presence of enormous nutrient potential as well as bioactive *** review mainly focuses on the potential of edible insect for its diverse nutraceutical properties,production and processing as a functional food and its acceptance and boost in the market trends in global *** consumption of edible insects is purely based on ethnic traditional knowledge of the local *** studies on edible insects have shown their potential as source of nutraceuticals with promote health benefit and can be an alternative source of *** of the edible insects are rich source of protein,energy,vitamins,essential fatty acids and *** these insects can be a source of bioactive compounds especially peptides,which can be applied in functional food *** many countries,the traditional knowledge of entomophagy is being applied for production of value-added products using modern technology.

关键词： Edible insects Functional foods nutrition Biotechnology approaches

Adaptive evolution of sucrose specific hydrolase in Lepidoptera

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Adaptive evolution of sucrose specific hydrolase in Lepidopt...