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A nanobody-based blocking enzyme-linked immunosorbent assay for detecting antibodies against pseudorabies virus glycoprotein E

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Journal of Integrative Agriculture 2024年第4期23卷 1354-1368页

作者： Huanhuan Lü Pinpin Ji Siyu liu Ziwei Zhang Lei Wang Yani Sun baoyuan liu Lizhen Wang Qin Zhao Department of Preventive Veterinary Medicine College of Veterinary MedicineNorthwest A&F University/Shaanxi Scientific Observing and Experimental Station of Veterinary Pharmacology and Diagnostic TechnologyMinistry of Agriculture and Rural AffairsYangling 712100China

Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry *** glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ELISA)has been used to distinguish gE-deleted vaccine-immunized pigs from wild-type virus-infected pigs to eradicate PR in some *** has the advantages of small size and easy genetic engineering and has been a promising diagnostic ***,there were few reports about developing nanobody-based ELISA for detecting anti-PRV-gE *** the present study,the recombinant PRV-gE was expressed with a bacterial system and used to immunize the Bactrian ***,two nanobodies against PRV-gE were screened from the immunized camel by phage display ***,two nanobody-HRP fusion proteins were expressed with HEK293T *** PRV-gE-Nb36-HRP fusion protein was selected as the probe for developing the blocking ELISA(bELISA)to detect anti-PRV-gE *** optimizing the conditions of bELISA,the amount of coated antigen was 200 ng per well,and dilutions of the fusion protein and tested pig sera were separately 1:320 and 1:*** cut-off value of bELISA was 24.20%,and the sensitivity and specificity were 96.43 and 92.63%,*** detecting 233 clinical pig sera with the developed bELISA and a commercial kit,the results showed that the coincidence rate of two assays was 93.99%.Additionallly,epitope mapping showed that PRV-gE-Nb36 recognized a conserved conformational epitope in different reference PRV ***,great stability and low-cost nanobody-based bELISA for detecting anti-PRV-gE antibodies were *** bELISA could be used for monitoring and eradicating PR.

关键词： nanobody nanobody-HRP blocking ELISA PRV-gE antibody

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沉香多级提取物的化学成分及释香行为

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林业科学 2024年第7期60卷 129-139页

作者：陈媛吴德淮晏婷婷赵莹刘宝元李改云中国林业科学研究院木材工业研究所北京100091 国家燃香类产品质量监督检验中心 (福建)泉州362600 海南那大农业开发有限公司儋州571724

[目的]沉香提取物是其主要应用方式之一。针对不同应用领域对沉香成分需求存在显著差异的问题,在提取过程中对沉香主要成分进行粗犷分离,明确不同提取物的释香行为,为实现沉香在特定领域的定向、高效利用提供参考。[方法]以传统沉香和... 详细信息

[目的]沉香提取物是其主要应用方式之一。针对不同应用领域对沉香成分需求存在显著差异的问题,在提取过程中对沉香主要成分进行粗犷分离,明确不同提取物的释香行为,为实现沉香在特定领域的定向、高效利用提供参考。[方法]以传统沉香和奇楠沉香为研究对象,通过水蒸气-溶剂多级提取,获得精油、浸膏、醇沉等沉香多级提取物;利用气相色谱质谱联用(GC-MS)和高效液相色谱(HPLC)技术,分析不同品种沉香多级提取物的化学成分差异;采用顶空-气相色谱联用(HS-GC-MS)技术,分析传统沉香和奇楠沉香多级提取物在40~160℃的香气释放规律。[结果]水蒸气-溶剂多级提取可实现传统沉香和奇楠沉香中倍半萜、色酮类成分的粗犷分离;水中蒸馏和隔水蒸馏对精油成分影响较小,均主要含有倍半萜和芳香族小分子物质,相对峰面积≥99%;蒸馏后再进行溶剂提取,获得的浸膏主要含有色酮类成分,相对峰面积≥90%;醇沉可实现对传统沉香浸膏中杂质的有效分离。2种沉香多级提取物的主要化学成分和释香成分存在显著差异:传统沉香、奇楠沉香精油中,分别主要含有榄香醇、α-檀香醇,40℃时主要释香物质分别为匙叶桉油烯醇、(1R,3aR,5aR,9aS)-1,4,4,7-Tetramethyl-1,2,3,3a,4,5a,8,9-octahydrocyclopenta[c]benzofuran;传统沉香浸膏中色酮种类更为丰富,160℃后色酮裂解形成大量小分子挥发性物质,出峰数量和强度明显高于奇楠沉香。[结论]通过多级提取方式,可获得富含倍半萜类化合物的沉香精油以及富含色酮类成分的沉香浸膏、杂质较高的醇沉。精油在低温时具有较好的香气释放能力,适合开发香水、日化等常温释香产品;浸膏适用于高温释香,可开发熏香、燃香等产品;奇楠沉香浸膏中主要成分为2-(2-苯乙基)色酮、2-[2-(4-甲氧基苯基)乙基]色酮,可用于该色酮的单体分离;醇沉中沉香有效物质明显降低,可开发低值化产品。

关键词：沉香奇楠多级提取化学成分释香

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基于CSLE的泛第三极地区土壤侵蚀强度空间分布特征

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水土保持研究 2024年第3期31卷 1-9页

作者：刘子玥章文波殷兵杨勤科魏欣刘宝元殷水清北京师范大学地理科学学部北京100875 西北农林科技大学水土保持研究所陕西杨凌712100 西北大学城市与环境学院西安710127

[目的]定量评估泛第三极地区的土壤侵蚀状况,明确土壤侵蚀的分布特征,以期为土壤侵蚀的科学防治提供依据。[方法]基于分层不等概系统抽样方法,共布设31 406个调查单元。利用中国土壤流失方程CSLE计算泛第三极地区土壤侵蚀速率,并利用莫... 详细信息

[目的]定量评估泛第三极地区的土壤侵蚀状况,明确土壤侵蚀的分布特征,以期为土壤侵蚀的科学防治提供依据。[方法]基于分层不等概系统抽样方法,共布设31 406个调查单元。利用中国土壤流失方程CSLE计算泛第三极地区土壤侵蚀速率,并利用莫兰指数(I)探讨其分布特征。[结果](1)泛第三极地区平均土壤侵蚀速率为162.73 t/(km^(2)·a),水土流失面积比例为7.75%,土壤侵蚀速率超过500 t/(km^(2)·a)的地区主要位于西亚、东亚和南亚;(2)土壤侵蚀存在明显的空间聚集性(I=0.920 9),以高高型和低低型聚集为主,高高型聚集主要分布在西亚北部、南亚北部和西南部以及中国的东北、黄土高原和西藏南部;(3)草地、灌丛和耕地是土壤侵蚀较严重的土地利用类型,其中>1 000 m的草地、>500 m的灌丛和耕地的土壤侵蚀更严重,超过25%的土地都发生了水土流失,平均土壤侵蚀速率变化于426.85~683.72 t/(km^(2)·a)。[结论]海拔介于1 000~6 000 m的草地、500~4 000 m的灌丛以及1 000~4 000 m的耕地是泛第三极地区土壤侵蚀发生的重点区域,需特别关注。

关键词：土壤侵蚀泛第三极空间分布莫兰指数

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东北黑土区防风林带基本特性及其与风向的关系

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水土保持学报 2024年第3期38卷 207-215页

作者：马逸雪刘宝元张蒙娜董丽霞张庚北京师范大学地理科学学部北京100875 北京师范大学地表过程与资源生态国家重点实验室北京100875 北京师范大学自然科学高等研究院广东珠海519087

[目的]为探究东北黑土区防风林带走向与主害风向的关系。[方法]利用遥感解译和野外调查,获取研究区内林带基本特征数据,结合研究区内43个气象站点风速风向数据,对林带走向与主害风向的交角,即风向偏角进行计算分析。[结果]蒙东黑土亚区... 详细信息

[目的]为探究东北黑土区防风林带走向与主害风向的关系。[方法]利用遥感解译和野外调查,获取研究区内林带基本特征数据,结合研究区内43个气象站点风速风向数据,对林带走向与主害风向的交角,即风向偏角进行计算分析。[结果]蒙东黑土亚区偏西风占比大,风向较为集中,主害风主导性强烈,松嫩黑土亚区风向较为分散,主害风主导性较弱;平均林带密度松嫩黑土亚区>蒙东黑土亚区;防风林带走向在松嫩黑土亚区占比最大的为N-S走向林带,蒙东黑土亚区没有明显的规律性;研究区内风向偏角30°占比为70.40%,防风作用较差。[结论]研究区内大量防风林带走向与主害风向斜交,对主害风的防护作用较差。该研究结果对于了解现有防风林带密度、走向,进一步建设和改造防风林带有重要参考价值。

关键词：防风林带风力侵蚀林带走向主害风向

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Comparison and quantitative assessment of two regional soil erosion survey approaches

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International Soil and Water Conservation Research 2023年第4期11卷 660-668页

作者： Lixia Dong Suhua Fu baoyuan liu Bing Yin Faculty of Geographical Science Beijing Normal UniversityBeijing100875PR ChinaFaculty of Geographical ScienceBeijing Normal UniversityBeijing100875PR China Advanced Institute of Natural Sciences Beijing Normal University at Zhuhai519087PR China State Key Lab Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityPR China

Regional soil erosion surveys are the first step of soil conservation *** and sampling ap-proaches are commonly used for soil erosion surveys at the regional *** the grid approach,the region is divided into grids(e.g.,1 km × 1 km),and the soil erosion rate of each grid was *** the sampling approach,a small portion of the area(typically 4%or less)was taken and then the soil erosion rate was *** on the above calculation,both approaches evaluated the soil erosion area(which is the area where the soil erosion rate is greater than the soil loss tolerance(t))and its distribution in the whole *** purpose of this paper is to compare the assessment results of the two approaches and analyse their practicality using Yunyang County,Chongqing,China(area is 3636 km^(2)).The soil erosion rate,percentage of soil erosion area(PSEA,which is the ratio of the area where the soil erosion rate is greater than the soil loss tolerance(t)to the area of the total study region)and its spatial distribution were compared between the two *** results showed that the grid approach overestimated the average soil erosion rate and PSEA overall for all 33 sample units and the whole region in comparison to the sampling *** sampling approach can yield a reasonable spatial distribution of the soil erosion rate in the whole *** addition,the soil erosion regions were more clustered than those using the grid approach,which can be more suitable for soil conservation ***,the sampling approach is an efficient and practical approach in regional soil erosion *** results can provide insights into regional soil erosion surveys.

关键词： Regional soil erosion Soil erosion survey Grid approach Sampling approach CSLE

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Vegetation characteristics and soil properties in grazing exclusion areas of the Inner Mongolia desert steppe

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International Soil and Water Conservation Research 2023年第3期11卷 549-560页

作者： Wenbang Gao Hongtao Jiang Shuai Zhang Chunxing Hai baoyuan liu Faculty of Geographical Science Beijing Normal UniversityBeijing100875China College of Geographical Science Inner Mongolia Normal UniversityHuhhot010022China Advanced Institute of Natural Sciences Beijing Normal University at Zhuhai519087China

In arid and semi-arid desert steppe areas,grazing exclusion with fencing is widely regarded as an effective strategy for restoring degraded vegetation and enhancing the quality of degraded *** this study,we hypothesized that grazing exclusion caused by fencing enhances both vegetation and soil properties,and that the longer an area is fenced,the more considerable the *** conducted an observational study wherein random sampling was utilized to select 9 plots fenced for ten or more years,25 plots fenced for four to nine years,25 plots fenced for one to three years and 29 free-grazing plots within an area of approximately 63,000 km^(2)of Inner Mongolia desert steppe.A one-way ANOVA revealed no significant differences in the characteristics of grassland vegetation or soil properties between grasslands fenced for one to three years and free-grazing *** 4 years of fencing,noticeable increases in above-ground biomass,litter content,Simpson index,soil organic carbon,and available nitrogen were *** positive differences in vegetation coverage,height,species richness,soil available phosphorus,and available potassium were associated with plots with a minimum of 10 years of *** soil layer with the greatest difference in the fenced-in areas for soil organic carbon was at 0-25 *** available nitrogen and available phosphorus,fencing produced the most significant differences in the 0-20 cm soil layer,while for available potassium,fencing produced the most significant differences in the 0-30 cm soil ***,the fencing did not indicate any statistically significant differences in terms of clay,silt,and sand content in any soil *** data support our hypothesis that grazing exclusion improves both vegetation and soil properties,and that longer periods of grazing exclusion result in greater degrees of *** research offers technical guidance for the reasonable choice of fencing time across a vast area of the In

关键词： Fencingtime Soil restoration Vegetation Inner Mongolian desert steppe Grazing

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Responses of flood peaks to land use and landscape patterns under extreme rainstorms in small catchments-A case study of the rainstorm of Typhoon Lekima in Shandong,China

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International Soil and Water Conservation Research 2022年第2期10卷 228-239页

作者： Yuanhao liu Jianqiao Han Juying Jiao baoyuan liu Wenyan Ge Qingbin Pan Fei Wang Institute of Soil and Water Conservation Northwest A&F UniversityYangling712100Shaanxi ProvinceChina Key Laboratory of the Loess Plateau Soil Erosion and Water Loss Process and Control Ministry of Water ResourcesZhengzhou450003Henan ProvinceChina Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water ResourcesYangling712100Shaanxi ProvinceChina China Institute of Water Resources and Hydropower Resea

Investigations of the formation mechanisms of flood peaks in small catchments facilitate flood prediction and disaster prevention under extreme ***,there have been few studies on the re-sponses of flood peaks to land use landscape patterns using field surveys during extreme rainstorm *** on field data from 17 small catchments near the rainstorm center of Typhoon Lekima,7 landscape indices were *** flood peak and its sensitivity to the land use landscape were investigated by combining remote sensing interpretation and related *** conclusions are as follows:(1)The peak discharge of the small catchment was 2.36e56.50 m3/s,the peak modulus was 8.00 e48.89 m3/(s$km2),and the flood index K ranged from 3.61 to 4.55.(2)Under similar rainfall conditions,the flood peak modulus,K and the proportion of sloping cropland had significantly positive correlations(p<0.05).The flood peak modulus was significantly negatively correlated with the proportion of forest-grassland and terrace(p<0.05),and K and the proportion of forest-grassland and terraced land exhibited a negative correlation.(3)The flood peak modulus and K were positively correlated with the landscape fragmentation.(4)The sensitivities of small catchments to floods were evaluated to be moderate compared to K values from other *** ability of small catchments to cope with extreme rain-storms can be improved by increasing the areas of forest-grassland,and terraces and reducing landscape *** results could be applied to provide a basis for land use planning and support for the response against disasters caused by extreme floods.

关键词： Extreme rainstorm Flood peak intensity Flood peak sensitivity Land use Landscape pattern

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Quantifying spatial distribution of interrill and rill erosion in a loess at different slopes using structure from motion(SfM)photogrammetry

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International Soil and Water Conservation Research 2022年第3期10卷 393-406页

作者： Tao He Yang Yang Yangzi Shi Xiaozhen Liang Suhua Fu Gege Xie baoyuan liu Yingna liu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China School of Geography Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China Beijing Key Laboratory of Environmental Remote Sensing and Digital Cities Faculty of Geographical ScienceBeijing Normal UniversityBeijing100875China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Chinese Academy of Sciences and Ministry of Water ResourcesYangling712100China

The spatial distribution of interrill and rill erosion is essential for unravelling soil erosion principles and the application of soil and water conservation *** quantify interrill and rill erosion and their spatial development,four 30-min rainfalls at 90 mm h^(-1)intensity were consecutively simulated on runoff plots packed with a loess at six slopes of 10°,15°,20°,25°,30°and 35°.The soil surface was measured using the structure from motion(SfM)photogrammetry upon each simulation run,and the runoff and sediment samples were collected and measured at every 10 *** did not develop until the third simulation *** the initial two runs,the lower third section was more severely eroded than the upper and middle thirds along the slope direction,yet the interrill erosion was statistically uniform from left to *** tended to emerge by both sidewalls and in the lower portion in the third *** corresponding rill erosion increased with slope from 10°to 20°and then decreased for the slopes steeper,which was consistent with the slope trend of the sediment yield directly *** rills expanded substantially primarily via head retreat and to a lesser extent via sideward erosion after receiving another 30-min *** erosion contributed 69.3%of the total erosion loss,and shifted the critical slope corresponding to the maximum loss from 20°to 25°.These findings demonstrate the significance of rill erosion not only in total soil loss but also in its relation to slope,as well as the effectiveness of SfM photogrammetry in quantifying interrill and rill erosion.

关键词： Interrill and rill erosion Spatial distribution Structure from motion(SfM) photogrammetry Slope Rainfall simulation

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Unpaved road erosion after heavy storms in mountain areas of northern China

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International Soil and Water Conservation Research 2022年第1期10卷 29-37页

作者： Chunmei Wang baoyuan liu Qinke Yang Guowei Pang Yongqing Long Lei Wang Richard M.Cruse Weiqin Dang Xin liu Enheng Wang Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi'an710127PR China Key Laboratory of National Forestry and Grassland Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an710048PR China Advanced Institute of Natural Sciences Beijing Normal University at ZhuhaiZhuhai519087PR China State Key Laboratory of Earth Surface Processes and Resource Ecology School of GeographyBeijing Normal UniversityBeijing100875PR China Department of Agronomy Iowa State UniversityAmesIA50011USA Suide Experimental Station for Soil and Water Conservation the Yellow River Conservancy CommissionYulinShaanxi719000PR China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbinHeilongjiang150040PR China

More frequent extreme rainfall events associated with global climate change cause greater challenges for soil *** erosion occurs on many unpaved roads since these structures create important water flow paths during heavy *** present research aimed to investigate the intensity and influencing factors of unpaved road erosion under varied land use and management conditions(sloping cropland,terraced cropland,forest&grass).The erosion occurred in the watersheds contributing runoff water to roads after the greatest rainfall event recorded in the mountain area of northern China caused by Typhon *** research was conducted in an agricultural-forest-dominated watershed based on field investigation and UAV-based image analysis.A road erosion level classification standard was given according to the occurrence of rills,ephemeral gullies,and *** erosion happened on 67% of the unpaved roads;42% of them suffered moderate to severe erosion in which ephemeral gullies or gullies *** average erosion amount from these roads was 2280.75 t ha-1 and was significantly influenced by the watershed land use type and *** dominant factor governing unpaved road erosion associated with terraced cropland was vegetation coverage on *** area was the most important factor for road erosion in sloping cropland and forest&grass land,and road gradient was also a critical ***,and forest&grass in drainage areas significantly reduced unpaved road erosion by 85%and,47%,respectively,compared to sloping *** integrated measures should be used to prevent unpaved road *** results of this research can be applied to road protection against erosion in heavy storms.

关键词： Unpaved road erosion Heavy storm Gully Land management Climate change

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Call for joint international actions to improve scientific understanding and address soil erosion and riverine sediment issues in mountainous regions

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International Soil and Water Conservation Research 2023年第3期11卷 586-588页

作者： Fan Zhang baoyuan liu Liping Zhu Richard Cruse Dongfeng Li Panos Panagos Pasquale Borrelli Yakov Kuzyakov Shaoshan An State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina Beijing Normal University BeijingChina Agronomy Department at Iowa State University AmesIAUnited States Department of Geography National University of SingaporeKent RidgeSingapore European Commission Joint Research CentreIspraItaly Department of Environmental Sciences Environmental GeosciencesUniversity of BaselBaselSwitzerland Department of Science Roma Tre UniversityRomeItaly Department of Soil Science of Temperate Ecosystems Department of Agricultural Soil ScienceGeorg-August-University of GottingenGermany Research Center of Water and Soil Conservation and Ecological Environment Chinese Academy of Sciences&Ministry of EducationYanglingShaanxiChina

During the International Workshop on Soil Erosion and Riverine Sediment in Mountainous Regions held in November 2022,scientists from many countries shared their state-of-the-art knowledge and brainstormed to improve scientific understanding for coping with climate change and anthropogenic *** summarized in this discussion includes proposed key scientific questions and suggested joint actions to reduce soil erosion and riverine sediment problems in mountainous regions.

关键词： soil mountainous summarized

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