Multi-scale habitat selection modeling: introduction to the special issue     

Kevin McGarigal  Kathy A. Zeller  Samuel A. Cushman 《Landscape Ecology》2016,31(6):1157-1160

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Screening for Rift Valley fever infection in northern Somalia: a GIS based survey method to overcome the lack of sampling frame     

Soumare B  Tempia S  Cagnolati V  Mohamoud A  Van Huylenbroeck G  Berkvens D 《Veterinary microbiology》2007,121(3-4):249-256

Following repeated import bans imposed by Saudi Arabia on livestock originated from Somalia due to suspicion of Rift Valley fever (RVF) presence and the severe socio-economic consequences of this, it was imperative for the Somaliland government to carry out surveillance activities in order to determine the status of transboundary diseases in its territory. A GIS computer software (Arcview) was used to overcome the lack of lists of sampling sites due to the high mobility of pastoral nomadic herds in the study area. This method proved very convenient and flexible for the random selection of sampling sites and thus the compliance with the requirements by the World Organisation for Animal Health (OIE) for statistically valid methods if the surveillance outcome is to meet international recognition and acceptance. Screening in Somaliland in 2001 and in Puntland in 2003 which targeted mainly sheep and goats aged 1-2 years (97% of surveyed animals) revealed no signs compatible with the disease but an overall sero-prevalence of 2+/-0.02% (90/4570) and 5+/-0.3% (206/4050), respectively. The spatial distribution showed clusters of high sero-prevalence located mostly in the Nugal Valley. This trend was confirmed by the follow-up survey implemented in Somaliland in 2004 with a herd prevalence of 80+/-6% and a within-herd prevalence up to 50% located again in the Nugal Valley. This result suggests the maintenance and increase of RVF virus activity in the valley. In addition conditions favourable to the breeding and survival of the vector population and the high density of livestock make the Nugal Valley an area of high risk for a RVF outbreak where sentinel herds will be placed.  相似文献   

Bayes and diagnostic testing     

Lesaffre E  Speybroeck N  Berkvens D 《Veterinary parasitology》2007,148(1):58-61

Interpretation of the result of a diagnostic test depends not only on the actual test result(s) but also on information external to this result, namely the test's sensitivity and specificity. This external information (also called prior information) must be combined with the data to yield the so-called updated, posterior estimates of the true prevalence and the test characteristics. The Bayesian approach offers a natural, intuitive framework in which to carry out this estimation process. The influence of the prior information on the final result may not be ignored. Guidance for the choice of prior information not in conflict with the data can be obtained from a set of statistics and indices (DIC, p(D), Bayes-p).  相似文献   

Role of sugars in surface microbe-host interactions and immune reaction modulation     

Lloyd DH  Viac J  Werling D  Rème CA  Gatto H 《Veterinary dermatology》2007,18(4):197-204

Sugars in the form of monosaccharides, oligosaccharides, polysaccharides and glycoconjugates (glycoproteins, glycolipids) are vital components of infecting microbes and host cells, and are involved in cell signalling associated with modulation of inflammation in all integumental structures. Indeed, sugars are the molecules most commonly involved in cell recognition and communication. In skin, they are essential to epidermal development and homeostasis. They play important roles in microbial adherence, colonization and biofilm formation, and in virulence. Two groups of pathogen recognition receptors, C-type lectins (CTL) and their receptors (CTLR), and the Toll-like receptors enable the host to recognize pathogen-associated molecular patterns (PAMPs), which are mainly glycolipids. The CTLs can recognize a wide variety of bacteria, fungi and parasites and are important in phagocytosis and endocytosis. TLRs are expressed on the surfaces of a variety of cells, including keratinocytes, dendritic cells, monocytes and macrophages; they play a major role in innate immunity. Interaction of TLRs with PAMPs initiates a cascade of events leading to production of reactive oxygen intermediates, cytokines and chemokines, and promotes inflammation. Exogenous sugars can block carbohydrate receptors and competitively displace bacteria from attachment to cells, including keratinocytes. Thus sugars may provide valuable adjunctive anti-inflammatory and/or antimicrobial treatment. A promising approach is the use of a panel of carbohydrate derivatives with anti-adhesive efficacy against bacteria frequently involved in diseases affecting skin and other epithelia. More complete characterization of sugar receptors and their ligands will provide further keys to use of carbohydrates in immunomodulation and infection control in skin.  相似文献   

Pattern recognition receptors in companion and farm animals - the key to unlocking the door to animal disease?     

Werling D  Coffey TJ 《Veterinary journal (London, England : 1997)》2007,174(2):240-251

The innate immune system is essential for host defence and is responsible for early detection of potentially pathogenic microorganisms. Upon recognition of microbes by innate immune cells, such as macrophages and dendritic cells, diverse signalling pathways are activated that combine to define inflammatory responses that direct sterilisation of the threat and/or orchestrate development of the adaptive immune response. Innate immune signalling must be carefully controlled and regulation comes in part from interactions between activating and inhibiting signalling receptors. In recent years, an increasing number of pattern recognition receptors (PRRs), including C-type lectin receptors and Toll-like receptors (TLRs), has been described that participate in innate recognition of microbes, especially through the so called pathogen-associated molecular patterns (PAMPs). Recent studies demonstrate strong interactions between signalling through these receptors. Whereas useful models to study these receptors in great detail in the murine and human system are now emerging, relatively little is known regarding these receptors in companion and farm animals. In this review, current knowledge regarding these receptors in species of veterinary relevance is summarised.  相似文献   

Langzeitwirkungen von Astungen im Holz von Linde und Roßkastanie     

Dirk Dujesiefken  Horst Stobbe  Dieter Eckstein 《European Journal of Forest Research》1998,117(1-6):305-315

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Rapid Identification of HMW Glutenin Subunits from Different Hexaploid Wheat Species by Acidic Capillary Electrophoresis     

Yueming Yan  Yi Jiang  Minmin Sun  Jianzhong Yu  Yinghua Xiao  Jigang Zheng  Yingkao Hu  Minhua Cai  Yaxuan Li  Sai L. K. Hsam  Friedrich J. Zeller 《Cereal Chemistry》2004,81(5):561-566

High molecular weight glutenin subunits (HMW‐GS) from three hexaploid wheat species (AABBDD, 2n=6x=42, Triticum aestivum L., T. spelta L., and T. compactum L.) were separated and identified by acidic capillary electrophoresis (A‐CE) with phosphate‐glycine buffer (pH 2.5) in uncoated fused‐silica capillaries (50 μm, i.d. × 25.5 cm) at 12.5 kV and 40°C. The rapid separations (<15 min) of HMW‐GS with good repeatability (RSD < 2%) were obtained using a fast capillary rising protocol. All 17 HMW‐GS analyzed could be well separated and their relative migration orders were ranked. In particular, the good quality subunit pair 5+10 could be differentiated from poor quality subunit pair 2+12. In addition, the other three allelic pairs of 13+16, 17+18, and 7+8 subunits that were considered to have positive effects on dough properties, as well as three pairs of novel subunits 13+22*, 13*+19*, and 6.1+22.1 detected from spelt and club wheat, can also be readily separated and identified. An additional protein subunit presented in Chinese bread wheat cultivar Jing 411 and club wheat TRI 4445/75, respectively, was detected by both A‐CE and 2‐D gel electrophoresis (A‐PAGE × SDS‐PAGE), for which further identification is needed.  相似文献   

Twin pregnancies following transfer of single embryos in three mares: A case report     

Patrick M. McCue DVM  PhD  Jill Thayer DVM  Edward L. Squires PhD  Steven P. Brinsko DVM  PhD  Dirk K. Vanderwall DVM  PhD 《Journal of Equine Veterinary Science》1998,18(12):832-834

Spontaneous development of identical or monozygotic twins is a rare event in the horse. Monozygotic twins develop after division of a single embryo. This report documents three cases in which twin embryos developed following surgical transfer of a single morula stage embryo into the uterus of a synchronized recipient mare.  相似文献   

Progress and challenges in freshwater conservation planning     

Jeanne L. Nel  Dirk J. Roux  Robin Abell  Peter J. Ashton  Richard M. Cowling  Jonathan V. Higgins  Michele Thieme  Joshua H. Viers 《水产资源保护:海洋与淡水生态系统》2009,19(4):474-485

• 1. Freshwater ecosystems and their associated biota are among the most endangered in the world. This, combined with escalating human pressure on water resources, demands that urgent measures be taken to conserve freshwater ecosystems and the services they provide. Systematic conservation planning provides a strategic and scientifically defensible framework for doing this.
• 2. Pioneered in the terrestrial realm, there has been some scepticism associated with the applicability of systematic approaches to freshwater conservation planning. Recent studies, however, indicate that it is possible to apply overarching systematic conservation planning goals to the freshwater realm although the specific methods for achieving these will differ, particularly in relation to the strong connectivity inherent to most freshwater systems.
• 3. Progress has been made in establishing surrogates that depict freshwater biodiversity and ecological integrity, developing complementarity‐based algorithms that incorporate directional connectivity, and designing freshwater conservation area networks that take cognizance of both connectivity and implementation practicalities.
• 4. Key research priorities include increased impetus on planning for non‐riverine freshwater systems; evaluating the effectiveness of freshwater biodiversity surrogates; establishing scientifically defensible conservation targets; developing complementarity‐based algorithms that simultaneously consider connectivity issues for both lentic and lotic water bodies; developing integrated conservation plans across freshwater, terrestrial and marine realms; incorporating uncertainty and dynamic threats into freshwater conservation planning; collection and collation of scale‐appropriate primary data; and building an evidence‐base to support improved implementation of freshwater conservation plans.

Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

Most fish destined for fishmeal production are food‐grade fish          下载免费PDF全文

Tim Cashion  Frédéric Le Manach  Dirk Zeller  Daniel Pauly 《Fish and Fisheries》2017,18(5):837-844

Marine fisheries target and catch fish both for direct human consumption (DHC) as well as for fishmeal and fish oil, and other products. We derived the fractions used for each for 1950–2010 by fishing country, and thus provide a factual foundation for discussions of the optimal use of fisheries resources. From 1950 to 2010, 27% (~20 million tonnes annually) of globally reconstructed marine fisheries landings were destined for uses other than DHC. Importantly, 90% of fish destined for uses other than DHC are food‐grade or prime food‐grade fish, while fish without a ready market for DHC make up a much smaller proportion. These findings have implications for how we are using fish to feed ourselves or, more appropriately, how we are not using fish to feed ourselves.  相似文献