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本文要点: ◆遗传型是机体全部遗传基因的总和,代表了个体的遗传潜力.在决定个体的解剖、生化、生理、行为等特性或遗传表型(如褐色的眼睛、75kg的体重、50 ml/kg/min的最大摄氧量等)上起主导作用.  相似文献   
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Purpose: This paper reports the results of survey research conducted with tribal producers between 2011 and 2012 on 19 of the largest American Indian reservations in Idaho, Nevada, North Dakota, Oregon, South Dakota, and Washington. The purpose of the research was to identify potential barriers to sustainable agriculture on reservation lands. This article reports the results of this research in an effort to promote Extension professionals' understanding of these barriers, which may help to improve outreach programs on American Indian reservations. Understanding the obstacles to sustaining agriculture that American Indian tribes face may inform international agricultural outreach efforts to increase food security targeting indigenous and tribal peoples worldwide.

Design/Methodology/Approach: American Indian agricultural producers comprised the study group. Study objectives included: (1) identify agricultural and natural resource issues of greatest concern to a self-selected sample of tribal agricultural producers on reservation lands; (2) evaluate access to Extension and other US Department of Agriculture outreach and assistance programs; and (3) evaluate the quality of these programs in terms of their relativity to tribal needs.

Findings: Study results indicate that tribal agricultural producers surveyed ranked 29 of 39 agricultural and natural resource issues as a concern. Similarly, they rated access to and quality of outreach programs as fair. Further, tribal producers operating on reservation trust land rated issues more severely than did tribal producers operating on fee simple lands.

Practical Implications: Results of this research will help Extension and other outreach professionals to understand the barriers indigenous and tribal peoples face in sustaining agricultural operations, particularly tribal groups living on federally reserved trust lands, such as American Indians. An increased understanding can inform agricultural policy-makers and outreach professionals in improving programs designed to increase agricultural sustainability, improve food security, enhance economic well-being and improve quality of life of indigenous and tribal peoples worldwide.

Originality/Value: This research provides important information to agricultural policy-makers and Extension professionals striving to sustain agricultural productivity and enhance food security with indigenous and tribal peoples.  相似文献   

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In order to understand how children's beliefs and cognitive performance vary according to development in their conceptions of effort and ability, 120 fourth and sixth graders were given the following assessments: (a) a measure of agency beliefs, defined as the extent to which persons believe they have access to certain classes of potential means, including effort, ability, powerful others, and luck; (b) a battery of intelligence test scales, including figural patterns, letter series, arithmetic, and spelling; (c) an interview designed to assess developmental levels in conceptions of effort and ability. Correlations between intelligence scores and agency beliefs for effort decreased with increasing levels of reasoning about effort and ability, but correlations between intelligence scores and agency beliefs for ability increased with increasing levels of reasoning. No such trends were found in correlations between performance and agency beliefs for luck or for unknown causes. The results are discussed in terms of the interaction between individual differences and developmental change.  相似文献   
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This article analyses how a Total Quality Management process with an embedded workplace literacy programme was implemented in an industrial manufacturing plant. Designed as an insider/outsider team research project, data were collected through interviews with management personnel, education and training providers, and hourly workers. Findings reveal that the Total Quality Management process and the literacy programme were implemented under the guise of providing education and training for workers, but were driven by corporate policy to reduce labour costs. The study also examines the way in which adult education was complicit in controlling workplace knowledge.  相似文献   
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Gobs of goo     
Ever touch something gooey? Stick your fingers in a jar of cold cream. Make some mud pies. Feel some spit. Ick!  相似文献   
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Florida-James G  Donaldson K  Stone V 《Journal of sports sciences》2004,22(10):967-80; discussion 980
Athens sits in a basin approximately 450 km2 in area, surrounded by mountains and open sea. Anthropogenic emissions in conjunction with the topographical and meteorological conditions can result in high air pollution within the city. The pollutants of concern for athletes competing in Athens 2004 appear to be nitrogen dioxide (NO2), ozone and particulate (PM10) pollution. Exposure to elevated ozone concentrations has been reported to give rise to symptoms that include cough, chest pain, difficulty in breathing, headache, eye irritation and a decrease in forced expiratory volume in one second. All of these effects are likely to impact upon performance, and several studies of cyclists suggest this to be the case. In contrast, the impact of ambient concentrations of NO2 appears to be negligible on normal activities, but at high exercise intensities the impact remains unclear. The use of currently available information and models to predict the effect of ozone and other pollutants on elite athletes is problematical, since such models are based upon significantly lower ventilation rates than those achieved by some elite athletes. In addition, it is already known that the response to ozone can vary somewhat between individuals. Since the individuals who will be competing in Athens are physiologically very different to the participants in most published studies, it is difficult to predict individual responses. There is some evidence to indicate that adaptation to the adverse health and performance effects of ozone can occur, so that performance is partially recovered on re-exposure. The adaptation is not seen in all studies and appears to be dependent on several factors, including the initial sensitivity of the individual to ozone. Antioxidant supplementation has also been shown in some studies to partially ameliorate the adverse effects of ozone by counteracting the oxidative stress mechanism associated with this pollutant. Whether this transfers to performance enhancement per se remains unclear at present. Additional research is required to gain a sound understanding of the effects of a complex mixed air pollution exposure on the pulmonary function and performance of athletes exercising at high work intensities.  相似文献   
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