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Biotechnology applications such as the use and production of genetically modified organisms (GMOs) have been widely promoted, adopted, and employed by agricultural producers throughout the world. Yet, little research exists that examines the implications of agricultural biotechnology on the health and safety of workers involved in agricultural production and processing. Regulatory frameworks do exist to examine key issues related to food safety and environmental protection in GMO applications. However, based on the lack of research and regulatory oversight, it would appear that the potential impact on the safety and health of workers is of limited interest. This article examines some of the known worker health and safety implications related to the use and production of GMOs using the host, agent, and environment framework. The characteristics of employers, workers, inputs, production practices, and socio-economic environments in which future agricultural workers perform various tasks is likely to change based on the research summarized here.  相似文献   
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Physiological responses to weaning procedures were studied in 21 foals assigned to one of five treatments: (1) abrupt, total separation of mare and foal, no preweaning creep feed (TSNC); abrupt, total separation with preweaning creep feed (TSC); partial separation of mare and foal allowing fenceline contact, no preweaning creep feed (PSNC); (4) partial separation with creep feed (PSC); and (5) control (CON) no separation of mare and foal, foals creep fed. Changes in adrenal response to exogenous ACTH, basal and peak plasma cortisol concentrations, plasma triiodothyronine (T3) and thyroxine (T4) concentrations, weight gains and feed consumption were measured. Foals on the total separation treatments had higher adrenal responses (P<.05) and pre-ACTH basal (P<.05) and post-ACTH peak plasma cortisol concentrations (P<.05) than foals on other treatments indicating they were stressed at weaning. The PSNC, PSC and CON treatments did not differ (P>.05) in any cortisol response. No treatment differences were found in thyroid hormone concentrations in this study. On partial separation treatments, creep-fed and non-creep-fed foals consumed similar amounts of feed during the first week postweaning. On total separation treatments, non-creep-fed foals consumed more feed (P<.05) than creep-fed foals. All foals without creep feed gained more weight immediately after weaning (0–2 weeks) than creep-fed foals (P<.05), reflecting higher feed intakes and possible compensatory gains. Total postweaning weight gains (0–8 weeks) of foals were not significantly affected by treatment.  相似文献   
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The use of native plants on green roofs has attracted considerable attention in recent years. With this comes the implicit assumptions that native plants are better adapted, provide greater environmental benefit, and are more aesthetically pleasing than non-native plants. We examined papers published in scholarly journals and papers presented at the annual North American green roof conference to identify who is promoting the use of native plants on green roofs, their rationale for doing so, and the scientific evidence to support the assertion that natives are better adapted. Architects, landscape architects, and biologists were the most likely to promote native plants and engineers were the least likely. Many of the reasons for using native plants on green roofs originate from ground-level landscaping and have simply been transplanted to the roof, without regard for the fact that the rooftop is a fundamentally different environment than the ground. Nearly half of all pro-native papers used the term “native” without definition. This review highlights the need for greater rigor and transparency when promoting the use of native plants and further demonstrates how misconceptions can result in sub-optimal green roof design and performance.  相似文献   
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Many compounds are being investigated for the control of symptoms of osteoarthritis in people and animals. Ideally, treatment should include analgesia, inflammation control, and chondroprotection. With further progress in this area, combination therapies tailored to the needs of the individual animal should enable us to maximize efficacy and minimize side effects. Only a few of the newer therapies and pharmaceutic agents have been investigated in the horse, however. With more rigorous investigation, they may be determined to be ineffective or unsafe. Meanwhile, as much information should be gathered from manufacturers as possible so as to ensure that appropriate recommendations are made.  相似文献   
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Purposeful introductions of exotic species for rehabilitation efforts following wildfire are common on rangelands in the western United States, though ecological impacts of exotic species in novel environments are often poorly understood. One such introduced species, Kochia prostrata (L.) Schrad (forage kochia) has been seeded on over 200 000 ha throughout the Intermountain West to provide fuel breaks and forage, and to compete with invasive plants. Despite its potential benefits, K. prostrata has been reported to spread from some seeded areas, and no studies have addressed its potential interactions with native species. A systematic investigation is needed to increase understanding of the extent to which K. prostrata spreads from seeded areas, the environmental conditions under which it spreads, and its interactions with the associated plant communities. We sampled 28 K. prostrata postfire rehabilitation and greenstrip seedings in southwestern Idaho, which ranged from 3 to 24 yr since seeding. We analyzed cover of K. prostrata and the associated plant community in adjacent seeded and unseeded areas, and quantified extent of spread from seeded areas. Abundance of K. prostrata was negatively associated with that of most plant functional groups, including native species, but was positively associated with abundance of exotic annual forbs. Kochia prostrata spread to unseeded areas on 89% of sampled sites; distances of the farthest individual from the seeding boundary were greater than those previously reported, ranging from 0 to 710 m, with a mean distance of 208 m. Further, although the area covered by K. prostrata increased with time since seeding, we found no evidence that plant community composition affected spread of K. prostrata. Results contribute to current understanding of potential ecological implications of seeding K. prostrata and will enhance the ability of land managers to make scientifically based management decisions about its use.  相似文献   
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