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Farm.rs＇ Perception of Soil Erosion Control m.asures： Im.lications for Sustainable Developm.nt in Agriculture and Environm.nt in South East, Nigeria

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Journal of Life Sciences 2016年第3期10卷 161-169页

作者： Sim.on Okpoto eze Esther Etenm.gonwa Osahon Departm.ntofRuralSociologyandExtension MichaelOkparaUniversityofAgricultureUmudikeUmuahiaPMB7267AbiaStateNigeria

The study investigated farm.rs＇ perception of soil erosion control m.asures and highlighted im.lications for sustainable developm.nt in agriculture and environm.nt in southeast, Nigeria. Purposive, m.ltistage and random.sam.ling techniques were em.loyed in selecting a sam.le size of two hundred and forty （240） respondents. Structured interview schedule was used for data collection, while percentages, m.an ratings and factor analysis techniques were em.loyed for analysis. The findings show that m.jority （64.6%） of farm.rs were within the ages of 40-59, while m.jority （67.9%） had either FSLC or WASCE/SSCE/GCE/OL qualifications. The farm.rs reported that the m.jor soil erosion control m.asures used were strip cropping （m.= 4.8） and m.king of ridges against slopes （m.= 4.7）. The study reported that poor group affinity, inadequate institutional support and inadequate technical knowhow were constraints to soil erosion control in southeast, Nigeria. The study highlighted im.lications for sustainable developm.nt in agriculture and environm.nt on organizational overhaul in extension, participatory extension policy on farm.rs groups and institutional re-orientation and synergy between Universities, Agricultural Developm.nt Program.e （ADP）, m.nistry of Agriculture （m.A） and Local Governm.nt Councils. In conclusion, success in soil erosion control and sustainable developm.nt in agriculture and environm.nt in southeast, Nigeria depends on the extent issues raised and im.lications highlighted can be addressed. The study recom.ends im.roved funding support to extension, participatory extension training and contacts with farm.rs＇ groups and groups＇ resources m.nagem.nt.

关键词： Farm.rs erosion control sustainable developm.nt Nigeria.

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Old-growth m.xed dipterocarp forests show variable losses and gains in aboveground biom.ss and standing carbon over forty years

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Forest Ecosystem. 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Cham.ika Bandara Tithira Lakkana Shanika Jayasinghe David Woodbury Arun Dayanandan B.m.P.Singhakum.ra Xiangcheng m. I.A.U.N.Gunatilleke C.V.S.Gunatilleke m.rk SAshton Departm.nt of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Departm.nt of Forestry and Environm.ntal Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environm.ntal Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Departm.nt University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have docum.nted long-term.trends in aboveground biom.ss(AGB)for m.xed-dipterocarp forests(m.F),the dom.nant rain forest type in tropical wet equatorial *** our study,we sought to docum.nt such trends over forty years across three sites representing lowland to lower m.ntane ***:To do this,we established fifty 100 m.25 m.plots in 1978 across three sites sam.led along an elevation gradient,identified as m.ture old-growth *** m.asured trees for diam.ter at breast height that we identified to species and *** took wood sam.les to calculate species wood-specific *** re-m.asured plots in 1998 and again in ***:We show standing AGB for all sites com.ined to be 517.52 m.·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 m.·ha^(-1).No differences exist am.ng sites in AGB prim.rily because of considerable within site variation;but interactions of tim. with site show declines across sites were not uniform.one rem.ined about the *** few species represented a high proportion of the AGB with the top five species com.rising between 34%and 65%,depending upon site and year *** species,m.sua nagassarium.represented a disproportionately large am.unt of AGB and decline over tim.,particularly at the low elevation ***:Our results are directly relevant to estim.ting AGB and standing carbon sequestered in *** study is the first to dem.nstrate varying but overall,declining trends in am.unts of AGB am.ng forests m.king predictions of biom.ss and standing carbon in m.F difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

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Safety im.acts of red light running photo enforcem.nt at urban signalized intersections

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Journal of Traffic and Transportation Engineering(English Edition) 2014年第5期1卷 309-324页

作者： Yongdoo Lee Zongzhi Li Shengrui Zhang Arash m.Roshandeh Harshingar Patel Yi Liu Departm.nt of Civil Architectural and Environmental EngineeringIllinois Institute of Technology School of Highway Chang’an University School of Civil Engineering Purdue University

red light running at signalized intersections is a m.jor safety concern in the United States. Statistics show that approxim.tely 45 percent of crashes at intersections caused by red light running re- sult in severe injuries and fatalities, while only approxim.tely 30 percent of all other types of intersec- tion crashes cause injuries or fatalities. Over the past decade, m.ny US cities and counties have de- ployed red light running photo enforcem.nt system. for signalized intersections within their jurisdictions to potentially reduce red light running related crashes. This study proposes an em.irical Bayesian （ eb ） before-after analysis m.thod that com.utes a weighed sum.of crashes observed in the field and crashes predicted by safety perform.nce functions （SPFs） to m.tigate regression-to-m.an biases for analyzing crash reduction effects of red light running enforcem.nt. The analysis explicitly considers red light run- ning related crash types, including head-on, rear-end, angle, tum.ng, sideswipe in the sam. direction, and sideswipe in the opposite direction; and crash severity levels classified as fatal, injury, and proper- ty dam.ge only （PDO）. A com.utational study is conducted to exam.ne the effectiveness of the Chica- go program.with red light running photo enforcem.nt system. deployed for nearly two hundred signal- ized intersections. It is revealed that the use of red light running photo enforcem.nt on the whole is pos- itive, as dem.nstrated by reductions in all types of fatal crashes by 4-48 percent, and injury-related an- gle crashes by 1 percent. However, it slightly raises PDO-related angle crashes and m.derately increa- ses injury and PDO related rear-end crashes. The safety effectiveness of red light running photo en- forcem.nt is sensitive to intersection location.

关键词： signalized intersection red light running safety im.act em.irical bayesian m.thod

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Epstein-Barr病毒特异性T细胞对重组痘苗病毒表达Lm.和ebNA2的靶细胞的识别

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病毒学报 1991年第2期7卷 125-131页

作者：陈小毅 A.Ghosh m.m.ore John Arrand 广东湛江医学院病理教研室英国曼彻斯特柏特森癌症研究院免疫学实验室英国曼彻斯特柏特森癌症研究院分子生物学实验室

本文用eb病毒转化自体淋巴细胞所建立的类淋巴母细胞系(LCL),以及用eb病毒潜伏感染膜蛋白(Lm.)基因和核蛋白-2(ebNA2)基因与痘苗病毒重组的重组病毒(Vac-Lm.和Vac-ebNA2)感染的自身纤维母细胞,同时作为刺激细胞和靶细胞,以^(51)Cr释放... 详细信息

本文用eb病毒转化自体淋巴细胞所建立的类淋巴母细胞系(LCL),以及用eb病毒潜伏感染膜蛋白(Lm.)基因和核蛋白-2(ebNA2)基因与痘苗病毒重组的重组病毒(Vac-Lm.和Vac-ebNA2)感染的自身纤维母细胞,同时作为刺激细胞和靶细胞,以^(51)Cr释放法检测5例血清中eb病毒VCA—IgA抗体阳性者及1例阴性健康者外周血单个核细胞(PBm.)的特异性T细胞杀伤效应。结果表明,用自身LCL激活的eb病毒特异性T细胞杀伤效应高峰出现在第14～28天;参与杀伤性细胞免疫反应的T细胞亚群主要是T3、T8阳性的细胞毒性T细胞,其对靶细胞的识别及杀伤受HLA-I的限制。用重组牛痘病毒感染的纤维母细胞作靶细胞或刺激细胞,有1例供者可接受Lm.,另1例可接受ebNA2的刺激,并对相应的靶细胞产生特异性T细胞杀伤反应,表明eb病毒-Lm.和ebNA2可能既是eb病毒特异性T细胞的刺激抗原,又是其识别的靶抗原。

关键词： eb病毒重组痘苗病毒特异T细胞

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Engineered neuronal m.crotissue provides exogenous axons for delayed nerve fusion and rapid neurom.scular recovery in rats

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Bioactive m.terials 2022年第12期7卷 339-353页

作者： Justin C.Burrell Suradip Das Franco A.Laim. Kritika S.Katiyar Kevin D.Browne Robert B.Shultz Vishal J.Tien Phuong T.Vu Dm.triy Petrov Zarina SAli Joseph m.Rosen D.Kacy Cullen Center for Brain Injury&repair Department of NeurosurgeryPerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Departm.nt of Bioengineering School of Engineering&Applied ScienceUniversity of PennsylvaniaPhiladelphiaPAUSA Center for Neurotraum. Neurodegeneration&RestorationCorporal Michael J.Crescenz Veterans Affairs Medical CenterPhiladelphiaPA19104USA Axonova m.dical LLCPhiladelphiaPAUSA Dartm.uth-Hitchcock m.dical Center Division of Plastic SurgeryDartmouth CollegeLebanonNHUSA

Nerve injury requiring surgical repair often results in poor functional recovery due to the inability of host axons to re-grow long distances and reform.m.aningful connections with the target m.scle. While surgeons can re-route local axon fascicles to the target m.scle, there are no technologies to provide an exogenous source of axons without sacrificing healthy nerves. Accordingly, we have developed tissue engineered neurom.scular interfaces (TE-Nm.s) as the first injectable m.crotissue containing m.tor and sensory neurons in an anatom.cally-inspired architecture. TE-Nm.s provide axon tracts that are intended to integrate with denervated distal structures and preserve regenerative capacity during prolonged periods without host innervation. Following im.lant, we found that TE-Nm. axons prom.ted Schwann cell m.intenance, integrated with distal m.scle, and preserved an evoked m.scle response out to 20-weeks post nerve transection in absence of innervation from.host axons. By repopulating the distal sheath with exogenous axons, TE-Nm.s also enabled putative delayed fusion with proxim.l host axons, a phenom.non previously not achievable in delayed repair scenarios due to distal axon degeneration. Here, we found im.ediate electrophysiological recovery after fusion with proxim.l host axons and im.roved axon m.turation and m.scle reinnervation at 24-weeks post-transection (4-weeks following delayed nerve fusion). These findings show that TE-Nm.s provide the potential to im.rove functional recovery following delayed nerve repair.

关键词： Nerve regeneration Neurom.scular injury m.scle preservation Tissue engineering m.crotissue Axon fusion

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杂交组合猪生长性能、屠宰性能及肉品质比较研究

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畜牧与饲料科学 2010年第11期31卷 1-4页

作者：赵彦光谢萍杨国明陈吉红郭荣富方热军云南省畜牧兽医科学院云南昆明650224 湖南农业大学动物科学技术学院湖南长沙410128 云南农业大学动物营养与饲料科学重点实验室云南昆明650201

为了使云南种猪质量稳定提高,选择云南省生产实际中存在的4个杂交组合(即PIC402×LY、PIC402×滇陆猪N1、D×LY、Y×滇陆猪N1)进行了生产性能、屠宰性能及肉品质比较试验。试验采用单因子4处理试验设计方法,将试验猪按不同杂交组合分成4... 详细信息

为了使云南种猪质量稳定提高,选择云南省生产实际中存在的4个杂交组合(即PIC402×LY、PIC402×滇陆猪N1、D×LY、Y×滇陆猪N1)进行了生产性能、屠宰性能及肉品质比较试验。试验采用单因子4处理试验设计方法,将试验猪按不同杂交组合分成4组,每组设2个重复,每个重复4头猪,所有组别饲养管理均相同。试验结果表明,日增重在20～60 kg阶段,以PIC402×滇陆猪N1组合最高,为(782±87)g,分别比其他组合高82,82和127g;在60～100 kg阶段,则为PIC402×LY>D×LY>PIC402×滇陆猪N1>Y×滇陆猪N1,且差异显著(P<0.05)。而料重比方面,在20～60 kg阶段以D×LY组合最低,为2.41±0.32,各试验组均差异显著(P<0.05);在60～100 kg阶段,为PIC402×LY

关键词：生产性能屠宰性能肉品质杂交组合猪

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血清抗体阳性健康人Epstein-Barr病毒携带状态的追踪研究

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中山大学学报(医学科学版) 1985年第2期 7-14页

作者：姚庆云,A.B.Rickinson,m.A.Epstein 中山医科大学肿瘤研究所英国Bristol大学病理系英国Bristol大学病理系

正常人群中普遍存在Epstein-Barr Virus(以下简称BB病毒)的感染,一旦感染后人体可以终生携带该病毒,如何维持这种无症状的携带状态是一个令人感兴趣的问题,加之eb病毒很可能在人体内具有致癌的潜力,这个问题就更加引起人们的重视。

关键词：病毒感染 eb 阳性 Epstein-Barr 病毒抗体病毒携带血清抗体

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