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Summary Guar is reported for the first time as a host of potato virus Y. The virus produced no symptoms, or occasional faint chlorotic
spots on inoculated cotyledons and unifoliate leaves. No symptoms were observed on new growth, but the virus was consistently
recovered from these leaves by back-inoculation to tobacco. Neither potato virus X nor cucumber mosaic virus infected guar. 相似文献
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M. T. Marino E. Ragozzino B. E. L. Lockhart R. Miglino D. Alioto 《Plant pathology》2008,57(2):394-394
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Soybean is the most important oilseed crop that is grown in India. Horse purslane (Trianthema portulacastrum L.) infests soybean heavily, causing enormous yield losses and threatening the sustainability of the soybean production system. Information on the interference and economic threshold of horse purslane will be useful for the effective management of horse purslane in soybean. This will lead to the rationalization of herbicide use and the reduction of herbicide input into the environment. It was observed in this study that “a composite stand of weeds including horse purslane”, and 200 horse purslane plants per m2 were equally competitive to soybean. These two treatments resulted in a higher dry weight, growth rate, and uptake of N, P, and K by the weeds and/or horse purslane, compared to the other treatments. They caused more reductions in soybean growth (dry weight, height, crop growth rate, net assimilation rate, and leaf area index) and resulted in a more significant yield reduction than did the other treatments. The weed density–crop yield and the relative leaf area–crop yield models were found to be equally effective in simulating soybean yield losses in relation to a wide range of horse purslane densities and the regression equations were a good fit. The quadratic equations revealed that a density of approximately six, five, and four horse purslane plants per m2 would be the economic threshold levels of horse purslane in soybean cultivation, when considering the 70, 80, and 90% horse purslane control efficiencies, respectively, of the herbicide, lactofen. 相似文献
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Messenger RNA levels were measured in actively dividing fibroblasts isolated from young, middle-age, and old-age humans and humans with progeria, a rare genetic disorder characterized by accelerated aging. Genes whose expression is associated with age-related phenotypes and diseases were identified. The data also suggest that an underlying mechanism of the aging process involves increasing errors in the mitotic machinery of dividing cells in the postreproductive stage of life. We propose that this dysfunction leads to chromosomal pathologies that result in misregulation of genes involved in the aging process. 相似文献
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Laura E Lockhart Alison A Motsinger‐Reif Wendy M Simpson Lysa P Posner 《Veterinary anaesthesia and analgesia》2014,41(1):48-53
ObjectiveThe current prevalence of onychectomy (declawing) in cats is unknown, and education regarding the procedure appears to vary greatly among veterinary schools. The purpose of this project was to determine the prevalence of onychectomized cats near Raleigh, NC and to document the frequency and style (laboratory or lecture) with which the procedure is taught in USA veterinary schools.AnimalsOne thousand seven hundred ninety four cats ranging in age from 8 days to 21 years, of which 938 (52.3%) were female and 1719 (95.8%) were sterilized.MethodsData were collected over a 10-week period regarding cats seen for appointments in five veterinary facilities (two cat-only, two general, and one tertiary). Data collection included signalment and onychectomy status. During this time, 28 veterinary schools were polled regarding education of veterinary students in onychectomy.ResultsThree hundred and seventy four (20.8%) cats had undergone onychectomy. A significantly higher percentage of declawed cats were seen in the general practices compared with the other practice types (p < 0.030). Younger cats had a higher rate of onychectomy (p < 0.001). Twenty-six veterinary schools responded to the survey (93%). Fourteen (54%) of the responding schools did not include in their core curriculum a lecture or surgical laboratory providing instruction in the onychectomy procedure.Conclusions and clinical relevanceAlmost 21% of cats seen in veterinary hospitals near Raleigh, NC were declawed. Less than 50% of veterinary schools in the USA include a mandatory lecture or laboratory to teach the procedure. There appears to be a discrepancy between the popularity of the onychectomy procedure and the emphasis placed on relevant instruction in veterinary schools in the USA. 相似文献
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Brian Roy Lockhart Emile S. Gardiner Theodor D. Leininger Kristina F. Connor Margaret S. Devall Paul B. Hamel Tracy Hawkins Nathan M. Schiff A. Dan Wilson 《Forest Policy and Economics》2009,11(8):539-547
The need for knowledge, ranging from development of new products or processes to the effects of specific actions on the environment, is greater now than at any point in the past. The greater need for research has generated stakeholder involvement in the research process. As a result, all facets of research, from planning through publication of results, are often scrutinized by stakeholders. While the basic nature of scientific inquiry has not changed, now more than ever the credibility of scientific results is based on thorough planning, peer reviews of experimental designs and analytical approaches, and assurance that data are of the highest quality. Public interest in the quality and accuracy of federal research rose to a level that resulted in the Data Quality Act of 2001. The Act required the establishment of guidelines for Federal research organizations and cooperators. We present a case study of the U. S. Forest Service's policies for research quality assurance and quality control, including developing quality assurance statements and plans, as applied to comprehensive research on the federally-listed, endangered forest shrub pondberry (Lindera melissifolia (Walt.) Blume). 相似文献