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571.
Kerry O’Donnell Ran Libeskind-Hadas Jiri Hulcr Craig Bateman Matthew T. Kasson Randy C. Ploetz Joshua L. Konkol Jill N. Ploetz Daniel Carrillo Alina Campbell Rita E. Duncan Pradeepa N. H. Liyanage Akif Eskalen Shannon C. Lynch David M. Geiser Stanley Freeman Zvi Mendel Michal Sharon Takayuki Aoki Allard A. Cossé Alejandro P. Rooney 《Phytoparasitica》2016,44(4):435-442
572.
It is often said that managing fisheries is managing people. This truism implies that fisheries science inherently involves disciplines that focus on fish and their population dynamics, humans and their behaviour, and policy and decision making. This is particularly true for recreational fisheries, where the human behavioural motivation and human response to management actions may be more difficult to predict than in commercial fisheries. We provide a synthesis of the multi‐disciplinary literature on modelling recreational angler behaviour to inform management of recreational fisheries. We begin by defining the recreational fisheries system in an interdisciplinary manner. We then assess the literature for empirical evidence of disciplinary crossover. Using bibliometric data, we provide evidence that there is little disciplinary crossover, particularly between fisheries biology, including applied ecology, and quantitative social science, including economics. We identify critical barriers to disciplinary crossover, such as database indexing issues and nomenclature. Next, we provide a review of critical contributions to the literature, and locate these contributions within our interdisciplinary conceptualization of the recreational fisheries system. This synthesis is intended to be a cross‐disciplinary bridge to facilitate access to the broader literature on modelling angler behaviour, with the ultimate goal of improving recreational fisheries management. 相似文献
573.
Diversification within fisheries operations can serve as an important form of self-insurance against natural, regulatory and market risks to fishers' livelihoods. Diversification can take many forms, and yet the literature has primarily emphasised diversification across species to the exclusion of spatial and temporal dimensions of diversification. We analyse trends in diversification across species, space and time for all fishers along the entire continental West Coast of the United States from 1990 to 2015. Our findings reveal the importance of untangling both compositional (i.e. driven by changes in fleet composition) and individual (i.e. driven by within-owner changes in diversification strategies) dimensions of diversification by showing how these effects have moved in contrary directions for all three forms of diversification. We also demonstrate how increases in temporal diversification have overwhelmed the overall stability of species and spatial diversification to leave the current fleet less exposed to financial variability compared to in the early 1990s. 相似文献
574.
Areas of mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks in the Black Hills can provide habitat for black-backed woodpeckers (Picoides arcticus), a U.S. Forest Service, Region 2 Sensitive Species. These outbreaks are managed through removal of trees infested with mountain pine beetles to control mountain pine beetle populations and salvage timber resources. To minimize impacts to black-backed woodpeckers while meeting management objectives, there is a need to identify characteristics of these areas that support black-backed woodpeckers. We examined the habitat associations of this species nesting in areas of beetle outbreaks in the Black Hills, South Dakota in 2004 and 2005. We used an information theoretic approach and discrete choice models to evaluate nest-site selection of 42 woodpecker nests at 3 spatial scales—territory, nest area, and nest tree. At the territory scale (250 m around nest), availability and distribution of food best explained black-backed woodpecker selection of beetle outbreaks versus the surrounding forest. Selection at the territory scale was positively associated with densities of trees currently infested by mountain pine beetles and indices of wood borer (Cerambycidae and Buprestidae) abundance, and was greatest at distances of 50–100 m from the nearest patch of infestation. At the nest-area scale (12.5 m radius around the nest), densities of snags positively influenced nest-area selection. Finally, at the nest-tree scale, aspen (Populus tremuloides) and 3–5-year-old ponderosa pine (Pinus ponderosa) snags were important resources. The association between abundant wood-boring insects and black-backed woodpeckers creates a difficult challenge for forest managers. In the absence of fire, areas of beetle outbreak might serve as the only substantial source of habitat in the Black Hills. Regulating insect populations via salvage logging will reduce key food resources to black-backed woodpeckers during nesting. Therefore, given the relatively infrequent occurrence of large-scale fire in the Black Hills, management should recognize the importance of beetle-killed forests to the long-term viability of the black-backed woodpecker population in the Black Hills. 相似文献
575.
The effect of warm storage (15°C) for 0, 15 or 31 days, applied after cold storage until April, and date of lifting to cold
storage on the physiological condition and field performance of two-year-old oak seedlings (Quercus robur L.) was investigated. Assessments before planting included plant moisture status, root and shoot dry weight, root growth
potential (RGP), while after planting root growth, shoot growth phenology, shoot and root dry matter accumulation and stem
quality were assessed. Warm storage effects were large, but lift date effects were small. Warm storage for 31 days reduced
height and diameter growth, stem quality, total biomass, root growth, and reduced stem quality in the field, but 15 days storage
had a smaller effect. Warm storage delayed bud break and shoot growth cessation but survival was unaffected. The depletion
of food reserves during storage and low moisture availability might have caused shoot dieback leading to the development of
poor quality stems. There was evidence that dry weight fraction of both the shoot tip and the taproot provided good information
on the quality of the stock before planting. RGP was also a good indicator of quality. Electrolyte leakage readings from fine
and taproots were not reliable indicators of plant quality. 相似文献
576.
Anna Shipov Amnon Sharir Elazar Zelzer Joshua Milgram Efrat Monsonego-Ornan Ron Shahar 《Veterinary journal (London, England : 1997)》2010,183(2):153-160
Many studies have described the effects of exercise restriction on the mammalian skeleton. In particular, human and animal models have shown that reduction in weight bearing leads to generalised bone loss and deterioration of its mechanical properties. The aim of this study was to assess the effect of prolonged exercise restriction coupled with heavy calcium demands on the micro-structural, compositional and mechanical properties of the avian skeleton. The tibiae and humeri of 2-year-old laying hens housed in conventional caging (CC) and free-range (FR) housing systems were compared by mechanical testing and micro-computed tomography (μCT) scanning. Analyses of cortical, cancellous and medullary bone were performed.Mechanical testing revealed that the tibiae and humeri of birds from the FR group had superior mechanical properties relative to those of the CC group, and μCT scanning indicated larger cortical and lower medullary regions in FR group bones. Cancellous bone analysis revealed higher trabecular thickness and a higher bone volume fraction in the FR group, but no difference in mineral density. The biomechanical superiority of bones from the FR group was primarily due to structural rather than compositional differences, and this was reflected in both the cortical and cancellous components of the bones. The study demonstrated that prolonged exercise restriction in laying hens resulted in major structural and mechanical effects on the bird skeleton. 相似文献
577.
Goldberg EE Kohn JR Lande R Robertson KA Smith SA Igić B 《Science (New York, N.Y.)》2010,330(6003):493-495
Identifying traits that affect rates of speciation and extinction and, hence, explain differences in species diversity among clades is a major goal of evolutionary biology. Detecting such traits is especially difficult when they undergo frequent transitions between states. Self-incompatibility, the ability of hermaphrodites to enforce outcrossing, is frequently lost in flowering plants, enabling self-fertilization. We show, however, that in the nightshade plant family (Solanaceae), species with functional self-incompatibility diversify at a significantly higher rate than those without it. The apparent short-term advantages of potentially self-fertilizing individuals are therefore offset by strong species selection, which favors obligate outcrossing. 相似文献
578.
Comparison of corneal degeneration and calcific band keratopathy from 2000 to 2013 in 69 horses
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579.
Objective
To describe a transorbital approach to the maxillary nerve block in dogs and compare it with a traditional approach.Study design
Prospective, randomized controlled study.Animals
Heads from 17 euthanized dogs (10 Greyhounds, three Border Collies and four of mixed breed).Methods
A volume of 1 mL of methylene blue dye was injected by each of two techniques, a traditional percutaneous approach and a transorbital approach to the maxillary nerve block. Both techniques were used on each head, alternating the left and right sides after random assignment to the first head. The heads were dissected to reveal the maxillary nerve and the length of nerve stained was measured.Results
There was no significant difference (p = 0.67) in the proportion of nerves stained for a length >6 mm by either technique (88.2% transorbital versus 82.3% percutaneous). The mean length of nerve stained did not differ significantly between the techniques (p = 0.26).Conclusions and clinical relevance
The transorbital approach to the maxillary nerve block described here presents a viable alternative to the traditional percutaneous approach. Further study is required to confirm its efficacy and safety under clinical conditions. 相似文献580.
J. T. Rando M. T. Reilly L. J. Cimetti A. C. D. Bueno 《Equine Veterinary Education》2017,29(8):417-421
An Appaloosa gelding presented for a traumatic puncture wound of the head ventral to the base of his left ear, bilateral epistaxis and upper respiratory compromise. The horse did not exhibit dysphagia or cranial nerve deficits. The horse suffered bilateral oblique fractures of both stylohyoid bones due to the traumatic incident, diagnosed upon endoscopy of the guttural pouches. Treatment consisted of anti‐inflammatory medication, broad‐spectrum antibiotics, guttural pouch lavage and dietary management with soft feeds. At a one‐month follow‐up examination, endoscopic evaluation revealed a union at both stylohyoid bone fracture sites. Guttural pouch mycosis was diagnosed in the left guttural pouch on the lateral wall at the entrance of the lateral compartment. The guttural pouch mycosis was treated with a nystatin and gentamicin flush, followed by a course of oral fluconazole. At the 3‐month re‐evaluation, the guttural pouch mycosis had completely responded to treatment. 相似文献