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61.
Robert A. Long Therese M. Donovan Paula MacKay William J. Zielinski Jeffrey S. Buzas 《Landscape Ecology》2011,26(3):327-340
Terrestrial carnivores typically have large home ranges and exist at low population densities, thus presenting challenges
to wildlife researchers. We employed multiple, noninvasive survey methods—scat detection dogs, remote cameras, and hair snares—to
collect detection–nondetection data for elusive American black bears (Ursus americanus), fishers (Martes pennanti), and bobcats (Lynx rufus) throughout the rugged Vermont landscape. We analyzed these data using occupancy modeling that explicitly incorporated detectability
as well as habitat and landscape variables. For black bears, percentage of forested land within 5 km of survey sites was an
important positive predictor of occupancy, and percentage of human developed land within 5 km was a negative predictor. Although
the relationship was less clear for bobcats, occupancy appeared positively related to the percentage of both mixed forest
and forested wetland habitat within 1 km of survey sites. The relationship between specific covariates and fisher occupancy
was unclear, with no specific habitat or landscape variables directly related to occupancy. For all species, we used model
averaging to predict occurrence across the study area. Receiver operating characteristic (ROC) analyses of our black bear
and fisher models suggested that occupancy modeling efforts with data from noninvasive surveys could be useful for carnivore
conservation and management, as they provide insights into habitat use at the regional and landscape scale without requiring
capture or direct observation of study species. 相似文献
62.
Replication of genome-wide association signals in UK samples reveals risk loci for type 2 diabetes 总被引:1,自引:0,他引:1
Zeggini E Weedon MN Lindgren CM Frayling TM Elliott KS Lango H Timpson NJ Perry JR Rayner NW Freathy RM Barrett JC Shields B Morris AP Ellard S Groves CJ Harries LW Marchini JL Owen KR Knight B Cardon LR Walker M Hitman GA Morris AD Doney AS;Wellcome Trust Case Control Consortium 《Science (New York, N.Y.)》2007,316(5829):1336-1341
The molecular mechanisms involved in the development of type 2 diabetes are poorly understood. Starting from genome-wide genotype data for 1924 diabetic cases and 2938 population controls generated by the Wellcome Trust Case Control Consortium, we set out to detect replicated diabetes association signals through analysis of 3757 additional cases and 5346 controls and by integration of our findings with equivalent data from other international consortia. We detected diabetes susceptibility loci in and around the genes CDKAL1, CDKN2A/CDKN2B, and IGF2BP2 and confirmed the recently described associations at HHEX/IDE and SLC30A8. Our findings provide insight into the genetic architecture of type 2 diabetes, emphasizing the contribution of multiple variants of modest effect. The regions identified underscore the importance of pathways influencing pancreatic beta cell development and function in the etiology of type 2 diabetes. 相似文献
63.
A common variant in the FTO gene is associated with body mass index and predisposes to childhood and adult obesity 总被引:2,自引:0,他引:2
Frayling TM Timpson NJ Weedon MN Zeggini E Freathy RM Lindgren CM Perry JR Elliott KS Lango H Rayner NW Shields B Harries LW Barrett JC Ellard S Groves CJ Knight B Patch AM Ness AR Ebrahim S Lawlor DA Ring SM Ben-Shlomo Y Jarvelin MR Sovio U Bennett AJ Melzer D Ferrucci L Loos RJ Barroso I Wareham NJ Karpe F Owen KR Cardon LR Walker M Hitman GA Palmer CN Doney AS Morris AD Smith GD Hattersley AT McCarthy MI 《Science (New York, N.Y.)》2007,316(5826):889-894
Obesity is a serious international health problem that increases the risk of several common diseases. The genetic factors predisposing to obesity are poorly understood. A genome-wide search for type 2 diabetes-susceptibility genes identified a common variant in the FTO (fat mass and obesity associated) gene that predisposes to diabetes through an effect on body mass index (BMI). An additive association of the variant with BMI was replicated in 13 cohorts with 38,759 participants. The 16% of adults who are homozygous for the risk allele weighed about 3 kilograms more and had 1.67-fold increased odds of obesity when compared with those not inheriting a risk allele. This association was observed from age 7 years upward and reflects a specific increase in fat mass. 相似文献
64.
65.
Therese M. Work Pete Weingartner Hugh J. Murphy Ronald Knight Business Lind Sanford Linda Best Florian I. Lauer Joe Pavek Shelley Jansky James Bryan M. D. Groskopp Charles R. Brown Richard G. Clarke John Guerard Jim Davis Rikki Sterrett John Ojala Joseph Guenthner 《American Journal of Potato Research》1989,66(11):769-790
66.
67.
Ruth H. True Therese M. Work Franklin E. Manzer 《American Journal of Potato Research》1982,59(2):65-67
Baked Monona and Abnaki potatoes from plants treated with Ridomil? 2EC on a 14 day schedule at the rate of 0.375 1b AI/A (1.5 pt formulation/A) were compared with an untreated control sample of the respective varieties by sensory panels of 13 and 18 members. No off-flavor was associated with the application of Ridomil at this level. 相似文献
68.
T. Rondahl J. Bertilsson E. Lindgren K. Martinsson 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3-4):137-147
Abstract In two repeated 3×3 Latin Square design trials, dairy cows have been fed bi-crop pea-oat silage to investigate the effect of maturity stage and harvest strategy on feed intake and milk production. In experiment 1 the crop was harvested when the peas were at the flat pod (cut 1) or full pod (cut 2) stage. At the first cut half of the forage was wilted and half was acid-treated with a 2:1 mixture of formic and propionic acid. At the second cut all of the forage was acid-treated. Voluntary intake was highest for the cut 2 silage. In experiment 2 the crop was harvested when the peas were at the flat pod (cut 1), pod fill (cut 2) or full pod (cut 3) stage. The crop was pre-wilted overnight and then acid-treated. Voluntary intake was highest for the cut 3 silage, although the in vivo apparent digestibility was lowest. Milk and protein yield increased with crop maturity. It was concluded that pre-wilting and acid treatment produces good quality, palatable pea-oat bi-crop silage. In terms of feed intake and milk production, the optimal time of harvest was when peas were at the pod fill stage and the oats were in the late milk to early dough stage. 相似文献
69.
Avian influenza virus (AIV) is enzootic to wild birds, which are its natural reservoir. The virus exhibits a large degree of genetic diversity and most of the isolated strains are of low pathogenicity to poultry. Although AIV is nearly ubiquitous in wild bird populations, highly pathogenic H5N1 subtypes in poultry have been the focus of most modeling efforts. To better understand viral ecology of AIV, a predictive model should 1) include wild birds, 2) include all isolated subtypes, and 3) cover the host’s natural range, unbounded by artificial country borders. As of this writing, there are few large-scale predictive models of AIV in wild birds. We used the Random Forests algorithm, an ensemble data-mining machine-learning method, to develop a global-scale predictive map of AIV, identify important predictors, and describe the environmental niche of AIV in wild bird populations. The model has an accuracy of 0.79 and identified northern areas as having the highest relative predicted risk of outbreak. The primary niche was described as regions of low annual rainfall and low temperatures. This study is the first global-scale model of low-pathogenicity avian influenza in wild birds and underscores the importance of largely unstudied northern regions in the persistence of AIV. 相似文献
70.
Susanna Sternberg Lewerin Marianne Elvander Therese Westermark Lisbeth Nisu Hartzell Agneta Karlsson Norstr?m Sara Ehrs Rickard Knutsson Stina Englund Ann-Christin Andersson Malin Granberg Stina B?ckman Per Wikstr?m Karin Sandstedt 《Acta veterinaria Scandinavica》2010,52(1):7
After 27 years with no detected cases, an outbreak of anthrax occurred in a beef cattle herd in the south of Sweden. The outbreak was unusual as it occurred in winter, in animals not exposed to meat-and-bone meal, in a non-endemic country.The affected herd consisted of 90 animals, including calves and young stock. The animals were kept in a barn on deep straw bedding and fed only roughage. Seven animals died during 10 days, with no typical previous clinical signs except fever. The carcasses were reportedly normal in appearance, particularly as regards rigor mortis, bleeding and coagulation of the blood. Subsequently, three more animals died and anthrax was suspected at necropsy and confirmed by culture and PCR on blood samples.The isolated strain was susceptible to tetracycline, ciprofloxacin and ampicillin. Subtyping by MLVA showed the strain to cluster with isolates in the A lineage of Bacillus anthracis.Environmental samples from the holding were all negative except for two soil samples taken from a spot where infected carcasses had been kept until they were picked up for transport.The most likely source of the infection was concluded to be contaminated roughage, although this could not be substantiated by laboratory analysis. The suspected feed was mixed with soil and dust and originated from fields where flooding occurred the previous year, followed by a dry summer with a very low water level in the river allowing for the harvesting on soil usually not exposed. In the early 1900s, animal carcasses are said to have been dumped in this river during anthrax outbreaks and it is most likely that some anthrax spores could remain in the area.The case indicates that untypical cases in non-endemic areas may be missed to a larger extent than previously thought. Field tests allowing a preliminary risk assessment of animal carcasses would be helpful for increased sensitivity of detection and prevention of further exposure to the causative agent. 相似文献