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31.
Aldicarb is taken up by earthworms from aqueous solution to give concentrations in the worms comparable to that in the external aqueous solutions. Uptake from waterlogged soils is similar, but much less aldicarb is taken up from drier soils. Aldicarb sulphoxide [2-methyl-2-(methylsulphinylpropionaldehyde O-methylcar-bamoyloxime], aldoxycarb and oxamyl are poorly taken up, giving concentrations in the worm of about 5% of the external aqueous concentration. In worms, aldicarb is rapidly converted to the sulphoxide which has a half-life in worms of 19 h at 15°C, and 50 h at 5°C. 相似文献
32.
Evaluation of humoral immunity to Brucella sp in cattle by use of an agar-gel immunodiffusion test containing a polysaccharide antigen 总被引:1,自引:0,他引:1
V R Lord M R Rolo J W Cherwonogrodzky 《American journal of veterinary research》1989,50(11):1813-1816
Results of a double agar gel immunodiffusion (Ouchterlony) test that contained a polysaccharide (poly-B) antigen of Brucella melitensis strain B115 were compared with those of 5 other serotests. To determine the sensitivity and specificity of the immunodiffusion, standard tube, 2-mercaptoethanol, Rivanol, card, and complement fixation tests, sera obtained from 1,328 vaccinated, infected, and seronegative cattle, 56 of which had been examined bacteriologically, were used to evaluate the humoral response to Brucella sp. The poly-B antigen confirmed infection in 87.5% of the 56 cattle from which Brucella abortus biotype 1 had been isolated, and in 96.6% (205/212) of a group of cattle suspected to be infected on the basis of results of conventional serotests. Likewise, sera from 4 groups of vaccinated cattle did not react with poly-B antigen, whereas they did react in conventional tests. The poly-B antigen was more specific in detecting infected cattle even in a group of vaccinated adults. A useful strategy to identify infected cattle might be screening, using a combination of the Rivanol and card tests together with the agar-gel immunodiffusion test containing poly-B antigen. 相似文献
33.
Peter F. Lord BVSc FRCVS Juan A. Gomez DVM PhD 《Veterinary radiology & ultrasound》1985,26(6):187-195
The radiographic changes caused by collapse of lung lobes in pulmonary disease, pneumothorax, and pleural effusion depend on the lobar recoiling force and local pleural pressure. Differences in the tendency of normal lung lobes or regions to collapse depend on the relative surface-to-volume ratio, determined by shape and size of the region or lobe. This ratio affects the physiologic parameters of pulmonary interdependence, compliance, and collateral air flow. Pulmonary surfactant increases compliance, particularly at low volumes, maintains alveolar stability, and assists in maintaining capillary patency and preventing pulmonary edema. Its loss due to lung injury increases collapsing forces. In the presence of pneumothorax or pleural effusion, diseases that cause lobar collapse produce localized air or fluid entrapment that is a diagnostic sign of the presence of the underlying pulmonary disease. 相似文献
34.
Abstract. The MAFF Nitrate Programme has provided policy makers and the agricultural industry with a much improved understanding of soil nitrogen cycling, and the cost-effectiveness of a range of nitrate reduction strategies. This understanding has been disseminated as improved economically-based advice on fertilizer N inputs to arable and grass crops, and information on the N value of livestock manures as affected by timing and method of application. In addition, strategies for reducing nitrate losses have been developed, including the use of over-winter cover crops, the management of cultivations and crop residues, and the conversion of arable land to low-input grassland.
A wide variety of information dissemination methods have been used, including face-to-face discussions, demonstrations, articles in the farming press, booklets aimed at farmers, technical information for advisers and consultants, recommendation reference books and computer-based fertilizer recommendation systems. 相似文献
A wide variety of information dissemination methods have been used, including face-to-face discussions, demonstrations, articles in the farming press, booklets aimed at farmers, technical information for advisers and consultants, recommendation reference books and computer-based fertilizer recommendation systems. 相似文献
35.
Ellen K Pikitch Konstantine J Rountos Timothy E Essington Christine Santora Daniel Pauly Reg Watson Ussif R Sumaila P Dee Boersma Ian L Boyd David O Conover Philippe Cury Selina S Heppell Edward D Houde Marc Mangel Éva Plagányi Keith Sainsbury Robert S Steneck Tess M Geers Natasha Gownaris Stephan B Munch 《Fish and Fisheries》2014,15(1):43-64
Forage fish play a pivotal role in marine ecosystems and economies worldwide by sustaining many predators and fisheries directly and indirectly. We estimate global forage fish contributions to marine ecosystems through a synthesis of 72 published Ecopath models from around the world. Three distinct contributions of forage fish were examined: (i) the ecological support service of forage fish to predators in marine ecosystems, (ii) the total catch and value of forage fisheries and (iii) the support service of forage fish to the catch and value of other commercially targeted predators. Forage fish use and value varied and exhibited patterns across latitudes and ecosystem types. Forage fish supported many kinds of predators, including fish, seabirds, marine mammals and squid. Overall, forage fish contribute a total of about $16.9 billion USD to global fisheries values annually, i.e. 20% of the global ex‐vessel catch values of all marine fisheries combined. While the global catch value of forage fisheries was $5.6 billion, fisheries supported by forage fish were more than twice as valuable ($11.3 billion). These estimates provide important information for evaluating the trade‐offs of various uses of forage fish across ecosystem types, latitudes and globally. We did not estimate a monetary value for supportive contributions of forage fish to recreational fisheries or to uses unrelated to fisheries, and thus the estimates of economic value reported herein understate the global value of forage fishes. 相似文献
36.
Walleye Sander vitreus (Mitchill) are relatively resistant to experimental infection with VHSV IVb and extant walleye strains vary in susceptibility 下载免费PDF全文
J Grice A Reid A Peterson K Blackburn L Tubbs S Lord P Huber R Horricks B Dixon N C Bols J S Lumsden 《Journal of fish diseases》2015,38(10):859-872
37.
Thomas R. Carruthers Quang C. Huynh Adrian R. Hordyk David Newman Anthony D. M. Smith Keith J. Sainsbury Kevin Stokes Alexander Morison David Agnew Ana Parma Ignacio Sobrino Catherine Longo 《Fish and Fisheries》2023,24(2):279-296
Fisheries managers are in need of quantitative tools to inform decisions regarding selection of robust management practices, prioritising research gaps and stocks to focus on, particularly where there are limited resources or data. To support these decisions, the use of Management Strategy Evaluation (MSE), that is, closed loop simulation-testing of management procedures, is widely regarded as best practice. However, applying MSE is time- and computationally intensive, and requires highly skilled expertise and processes for stakeholder input and peer review. For data- and capacity-limited fisheries, MSE may be particularly challenging to implement. Yet, these are the contexts where it is most critical to test assumptions, evaluate the implications of all sources of uncertainty and identify the most informative data sources. To facilitate wider use of MSE, the Method Evaluation and Risk Assessment (MERA) framework was developed as an accessible online interface, with quick processing time, focused on generic data-limited management procedures, but allowing progression to tailored and more data-rich methods. The framework links a quantitative questionnaire and data input standard to a flexible operating model with optional customisation via command line access to the back-end open-source R libraries. Here, we illustrate a case study application of MERA for the bocinegro (Pagrus pagrus, Sparidae) fishery in the Gulf of Cadiz, where in conjunction with fishery stakeholders, a custom management procedure was developed and tested and key research gaps and data collection priorities were identified. We discuss implications for wider use of MSE in various contexts, including eco-certification and fishery improvement projects. 相似文献
38.
Liu W Jawerth LM Sparks EA Falvo MR Hantgan RR Superfine R Lord ST Guthold M 《Science (New York, N.Y.)》2006,313(5787):634
Blood clots perform an essential mechanical task, yet the mechanical behavior of fibrin fibers, which form the structural framework of a clot, is largely unknown. By using combined atomic force-fluorescence microscopy, we determined the elastic limit and extensibility of individual fibers. Fibrin fibers can be strained 180% (2.8-fold extension) without sustaining permanent lengthening, and they can be strained up to 525% (average 330%) before rupturing. This is the largest extensibility observed for protein fibers. The data imply that fibrin monomers must be able to undergo sizeable, reversible structural changes and that deformations in clots can be accommodated by individual fiber stretching. 相似文献
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