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11.
A 66 kDa adult Haemonchus contortus excretory/secretory (E/S) antigen was identified in Western blot by reaction with sera from the infected goats. The protein was purified from the adult worm extract and E/S products by anion exchange and ConA-Sepharose chromatography. The purified protein inhibited monocyte function in vitro as judged by decreased production of hydrogen peroxide and nitric oxide in the culture medium. The protein also caused proliferation of peripheral blood mononuclear cells. The absence of protein in the free living L3 larvae suggests that the expression of this protein coincides with the adaptation to the parasitic life. A correlation of antibody titre and worm burden was observed in the infected goats with higher antibody levels in high worm burdened animals. Anti-protein antibody caused loss of adult worm motility in vitro resulting in the death of the parasite. The fact that the protein is recognized by the host together with in vitro killing of adult parasites by antibodies makes this protein a promising candidate for vaccination trial. 相似文献
12.
Neelam C. Poudyal Carlotta Caplenor Omkar Joshi Cristina Maldonado Lisa I. Muller Chuck Yoest 《Human Dimensions of Wildlife》2017,22(6):538-549
Wild pigs are a free-ranging invasive species capable of inflicting significant damage on rural property. Wildlife management personnel may benefit from understanding the negative societal impact of wild pigs. A statewide mail survey of randomly selected landowners was conducted in rural Tennessee counties known to have wild pigs. The economic value of damage caused by wild pigs in 2015 in these counties was estimated at $26.22 million, whereas the cost incurred in control and eradication was $2.09 million. Input-output modeling of damage in these counties on the state’s economy showed $32.8 million in lost industrial output, $4.6 million in lost labor income, and 332 jobs or job equivalents affected. Findings are useful in understanding the types of damage, and the extent of these impacts on the rural economy. They could also facilitate comparing the expected benefit with the cost of control programs in Tennessee and comparable areas facing similar invasions from wild pigs. 相似文献
13.
Isolated mesophyll cells from leaflets of Arachis hypogaea can be cultured in a simple, defined liquid nutrient medium containing minerals, with an appropriate source of ammonia, sugar, 2,4-dichlorophenoxyacetic acid, and kinetin. The significance of such a simple medium in understanding the problems of cell metabolism, growth, and morphogenesis is discussed. 相似文献
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15.
Amaravadi RK 《Science (New York, N.Y.)》2011,334(6062):1501-1502
16.
Ratnaboli Bose Shailesh Pandey Pooja Joshi Sabyasachi Banerjee Amit Pandey Maneesh S. Bhandari 《Forest Pathology》2021,51(1):e12658
Eucalyptus spp. and their hybrids are frequently cloned and mass planted across farmland tracts and commercial plantations in northern India. It is a viable feeder species to the paper and pulp industries in this region. In 2018 and 2019, during field surveys conducted in northern India, a serious leaf blight disease was frequently observed in E. tereticornis plantations. Isolation from the blighted leaf samples consistently yielded fungal isolates having Calonectria‐like morphology. Morphological features coupled with sequence analysis of partial β‐tubulin (TUB2) and partial translation elongation factor‐alpha (TEF1) gene regions of two fungal isolates confirmed the species as Ca. cerciana. In detached leaf assays and glasshouse inoculation experiments, both isolates produced symptoms similar to those observed on the naturally infected leaves. Koch's postulates were fulfilled by re‐isolating Ca. cerciana from the inoculated leaves. This work is the first to confirm that Ca. cerciana is associated with a serious leaf blight disease of Eucalyptus in northern India and is an important addition to the taxonomy of Calonectria fungi in India. 相似文献
17.
FLORES, the Forest Land Oriented Resource Envisioning System, is a framework to facilitate quantitative modelling of ecological,
economic and social issues at the landscape scale. This issue ofSmall-scale Forest Economics, Management and Policy describes the evolution of FLORES from a concept to a series of models calibrated for diverse locations, and documents the
lessons learned.
The idea to construct and use landscape-scale models of the forest frontier, based on simulating household decisions and land
use at a spatial scale close to the field level, arose from a desire to add rigour to land-use policy research at CIFOR, the
Center for International Forestry Research (Vanclay 1995). This simulation modelling approach to addressing interdisciplinary
issues, where people are strongly interacting with forest resources, became known as FLORES, the Forest Land Oriented Resource
Envisioning System (Vanclay 1998). Muetzelfeldtet al. (1998) constructed a simple prototype of a FLORES model to illustrate the concept and demonstrate the ability of a system-dynamics
modelling environment to animate such a model (Muetzelfeldt and Taylor 1997, 2001, Muetzelfeldt and Massheder 2003). In 1999,
FLORES became a reality, when 50 scientists from diverse disciplines met in Bukittinggi, Indonesia to construct the first
FLORES model styled on this prototype (CIFOR 1999, Vanclayet al. 2003).
The research reported in this special issue was made possible by generous financial support from the Department for International
Development (UK), the European Community, the Asian Development Bank (under RETA 5812) and the Center for International Forestry
Research. The views expressed herein are those of the authors alone. We would like to thank the following people who have
assisted in the production of this special issue by acting as anonymous referees for these and other papers: Andy Warner,
Brendan Moran, Bruno Verbist, Chris Dake, Chris Legg, Doug Sheil, Euan Mason, Francois Bousquet, Frank Vanclay, Geoff Slaughter,
James Gambiza, John Herbohn, John Poulsen, Jungho Suh, Mike Spilsbury, Paul Phillips, Paul van Gardingen, Phil Norman, Philip
Nyhus, Roger Wheate, Ross Sigley, Steve Harrison and Tom Evans. Thanks also to the editorial staff, especially Steve Harrison,
John Herbohn and Jungho Suh, for making this special issue possible. 相似文献
18.
Mandy Haggith Ravi Prabhu Happyson Mudavanhu Frank Matose Tendayi Mutimukuru Richard Nyirenda Wavell Standa-Gunda 《Small-Scale Forestry》2003,2(2):155-169
This paper explores the challenge of defining the scope of a systems model, emphasising three aspects: boundary, granularity
and conceptual scope. The significance of these is illustrated by reference to a model of land-use decisions made in villages
bordering on the Mafungautsi forest in Zimbabwe. The purpose of this model was to help policy players (Forestry Commission
staff, non-governmental organisations, researchers and local people) to understand the impact of policy interventions on local
people’s livelihoods. Scoping decisions that were made in building the Mafungautsi model were deliberately liberal, to encompass
the interests of all participants in the modelling process. These decisions now present a range of serious challenges: the
difficulty of model calibration, the computational expense of running simulations, and the difficulty for new users to understand
the model. Facilitators of modelling teams need to consider the serious implications of giving everyone what they want and
including all participants’ ideas in a model. In the long run, it may be better to be tough and reject many suggestions at
the outset. The former approach is unlikely to lead to a tractable model, while the latter may ultimately offer greater satisfaction
for all.
We are grateful to the UK’s Department for International Development (DFID) and the European Community for financial support
of this project. Thanks also to all of the ACM team who have contributed ideas on the process and content of the modelling
work and who make it fun to undertake collaborative research. Thanks also to the participants in the Zimbabwe FLAC workshops
for their input into the specification of the Mafungautsi model. Finally thanks to Robert Muetzelfeldt, Jasper Taylor, Jonathan
Massheder, Fergus Sinclair and Jerry Vanclay for helping us to ride on the FLORES bandwagon. 相似文献
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