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91.
Chemical control of house flies in poultry production facilities is becoming increasingly difficult due to insecticide resistance and regulatory constraints. Biopesticides based on entomopathogenic fungi could provide an alternative approach. Here we evaluated population control potential of two fungal pathogens, Beauveria bassiana and Metarhizium anisopliae. Cohorts of adult flies were established in large plastic boxes in the laboratory and were exposed to residues of oil-formulated fungal conidia sprayed on strips of plastic sheeting attached to the box walls. Exposure to the biopesticide barrier treatments caused 100% mortality in adult populations within 8–16 days, depending on the fungal species. In contrast, control flies survived until 96–110 days. Additionally, fungal infections caused 13–20% reduction in egg viability and >70% reduction in fecundity of flies prior to death. The combined lethal and pre-lethal impacts resulted in 21- to 26-fold reduction in basic reproductive rate in the fungus-exposed populations relative to controls. Based on these promising proof-of-principle results, further research is currently under way to determine the feasibility of developing a biopesticide product for operational use.  相似文献   
92.
ABSTRACT In the Adirondack region of northern New York, USA, severe weather and deep snow typically force white-tailed deer (Odocoileus virginianus) to congregate in areas of dense coniferous cover and along watercourses at lower elevations. We examined 16 yards in the Adirondacks and explored the observation that deer have changed their movement behavior to incorporate residential communities within their wintering areas. We compared locations of deer herds in 2003 and 2004 to deer wintering areas mapped during the 1960s and 1970s. Deer were predominantly absent in 9 of 16 historical yards but were present in residential communities within the same drainage. Yarding areas to which deer shifted contained more residential, deciduous, and mixed cover than yards where no shift occurred, indicating that deer in residential areas were using conifer and mixed cover at a finer scale than deer in nonresidential areas. Smaller winter ranges and core areas of marked deer in a residential winter yard further imply greater concentration of resources available in these areas. Marked deer demonstrated flexibility in core winter range fidelity, a behavior that allows for more permanent shifts as habitat and food resources change or as new areas with appropriate resources are encountered. Our study suggests that low-density residential areas in lowland conifer forests may provide an energetic advantage for deer during winter due to the assemblage of quality habitat interspersed with open areas and a variety of potential food sources in environments where movement is typically constrained by deep snow. Managers should consider the potential for changes in use of deer wintering areas prior to land conservation efforts and may need to adapt management strategies to reduce conflicts in communities occupied by deer during winter.  相似文献   
93.
As human populations continue to expand across the world, the need to understand and manage wildlife populations within the wildland – urban interface is becoming commonplace. This is especially true for large carnivores as these species are not always tolerated by the public and can pose a risk to human safety. Unfortunately, information on wildlife species within the wildland – urban interface is sparse, and knowledge from wildland ecosystems does not always translate well to human‐dominated systems. Across western North America, cougars (Puma concolor) are routinely utilizing wildland – urban habitats while human use of these areas for homes and recreation is increasing. From 2007 to 2015, we studied cougar resource selection, human–cougar interaction, and cougar conflict management within the wildland – urban landscape of the northern Front Range in Colorado, USA. Resource selection of cougars within this landscape was typical of cougars in more remote settings but cougar interactions with humans tended to occur in locations cougars typically selected against, especially those in proximity to human structures. Within higher housing density areas, 83% of cougar use occurred at night, suggesting cougars generally avoided human activity by partitioning time. Only 24% of monitored cougars were reported for some type of conflict behavior but 39% of cougars sampled during feeding site investigations of GPS collar data were found to consume domestic prey items. Aversive conditioning was difficult to implement and generally ineffective for altering cougar behaviors but was thought to potentially have long‐term benefits of reinforcing fear of humans in cougars within human‐dominated areas experiencing little cougar hunting pressure. Cougars are able to exploit wildland – urban landscapes effectively, and conflict is relatively uncommon compared with the proportion of cougar use. Individual characteristics and behaviors of cougars within these areas are highly varied; therefore, conflict management is unique to each situation and should target individual behaviors. The ability of individual cougars to learn to exploit these environments with minimal human–cougar interactions suggests that maintaining older age structures, especially females, and providing a matrix of habitats, including large connected open‐space areas, would be beneficial to cougars and effectively reduce the potential for conflict.  相似文献   
94.
doi: 10.1111/j.1741‐2358.2011.00497.x
Oral health of the elderly living in residential homes in Slovenia Objectives:  To evaluate oral health status of the elderly, living in eight randomly selected residential homes for senior citizens across the country. Background: The percentage of the elderly is growing worldwide. With ageing, risks of various oral diseases, including dental caries and periodontal disease, are growing. Methods: Altogether 296 elderly people (88 men, 208 women) of average age 79.89 ± 7.4 years were questioned about their medical condition and oral health practice and examined orally. Evaluation of clinical examination was carried out by DMFT, plaque index ( 10 ) and Community Periodontal Index of Treatment Need (CPITN). Results: Of 296 participants, 106 (35.8%) were edentulous, 95 (32.1%) had one to nine teeth and 95 persons (32.1%) had 10 or more teeth. The average number of teeth in an individual was small: 6.76 ± 7.47. The average number of teeth with caries lesions was 3.59 ± 4.70, filled teeth 1.94 ± 3.63 and teeth without caries or fillings 1.19 ± 2.41. The average DMFT value was 30.75. In 69.5% of participants, dental plaque was visible with the naked eye. Of 171 subjects, in whom CPITN index was appraised, 81.9% would need oral hygiene education, 56.7% would need scaling and root planning and 21.6% would need periodontal surgical treatment. Conclusions: The results of this study indicate poor oral health of the elderly living in residential homes situated in different towns in Slovenia. It is of utmost importance to highlight the necessity of improving oral health care of this population.  相似文献   
95.
根据实验动物环境及设施国家标准(GB14925-2010)规定,结合公司的土建基础,综合考虑动物实验的要求,工程设计合理,施工规范。设施的各项指标均符合国家的相关标准。目前该设施总体运行良好,以下就该设施建设过程中的一些体会进行归纳。  相似文献   
96.
目的本实验以大型实验动物屏障设施为研究对象,分析屏障设施的环境微生物及尘埃粒子的动态变化规律及其相关影响因素。方法测定屏障设施各功能区域不同时间及不同工作状态下空气落下菌和直径≥0.3μm尘埃粒子的数量变化。结果屏障系统落下菌与尘埃粒子变化规律如下:屏障系统内空气落下菌与尘埃粒子在饲养工作后显著升高,喷雾消毒后明显降低;大、小鼠饲育室空气落下菌与尘埃数在凌晨时明显升高,而兔饲育室在凌晨时间段则较低;清洁走廊和污染走廊在工作状态时细菌含量明显上升,非工作状态时细菌含量一直处于较低的水平。结论实验动物屏障系统的环境微生物与尘埃粒子的动态数量变化与动物品种、空气消毒、人员进出及动物室内的饲养操作等有关。  相似文献   
97.
doi:10.1111/j.1741‐2358.2009.00281.x
Oral status among seniors in nine nursing homes in Styria, Austria Objective: To investigate the oral state in participants cared for in residences for senior citizens in Styria, Austria. Materials and methods: Four hundred and nine participants in Styria from nine homes for senior citizens were examined employing parameters in accordance with those of Folstein’s Mini Mental Status (MMS), DMFT, basic periodontal examination, the modified oral hygiene index, pain experienced during the preceding year, the subjective and objective need for treatment, and also requirements involving surgical and prosthetic treatment. Furthermore, the habitual methods of maintaining oral hygiene were examined establishing by whom this was carried out – whether by the patient, the nurse, or by patient and nurse together. Results: Four hundred and nine participants were examined, 48.3% were found to have retained on average 4.9 of their own teeth while 69% were fitted with dentures; however, 81% of the participants required prosthetic treatment. 28.9% of the participants had experienced acute dental pain during the preceding year and surgical treatment was found to be necessary in 47.7% of those with original teeth. Eighty‐four per cent of the participants showed acute inflammation of the periodontium while the state of oral hygiene, measured on a scale of 0–4, reached an average of 2.43. Oral hygiene was carried out by the nurses in only 7.46% of the cases which showed an average MMS measurement of 18. Conclusion: The results compared with those reported in other recent surveys and our data show an urgent need in Austria to improve the standards in dental care for the hospitalised elderly. Regular dental checks, carried out in the actual home by a dental surgeon should be introduced, whilst the nursing staff should be made fully aware of the problems caused by insufficient oral care and receive regular support from specialised oral hygiene assistants. The results of this survey also suggest that nursing staff should be equipped with simple instruments in order to judge to the extent to which the patient is capable of carrying out oral care independently and then according to the results to supplement this with additional care.  相似文献   
98.
严莹  李恺  杨辉 《昆虫知识》2010,47(6):1287-1293
在通常的城市绿地系统规划中,植物类型的选择和配置一般仅考虑其改善生态环境方面的效应。不同的植物群落上生活着不同的昆虫群落。在昆虫群落中,观赏性昆虫,譬如蝴蝶、蟋蟀和萤火虫等,则可作为一种新兴的生态景观应用于绿化中,可形成动态的景观。本文通过对崇明地区的观赏性昆虫类群调查及其与植物关系的理论分析,提出了适合崇明地区的观赏性昆虫造景方案,提供了营建生态小区的新思路。  相似文献   
99.
Physiological processes in organisms can be influenced by extremely low-frequency (ELF) electromagnetic energy. Biological effect studies have great importance; as well as measurement studies since they provide information on the real exposure situations. In this study, the leakage magnetic fields around a transformer were measured in an apartment building in Küçükçekmece, Istanbul, and the measurement results were evaluated with respect to the international exposure standards. The transformer station was on the bottom floor of a three-floor building. It was found that people living and working in the building were exposed to ELF magnetic fields higher than the threshold magnetic field value of the International Agency for Research on Cancer (IARC). Many people living in this building reported health complaints such as immunological problems of their children. There were child-workers working in the textile factories located in the building. Safe distances or areas for these people should be recommended. Protective measures could be implemented to minimize these exposures. Further residential exposure studies are needed to demonstrate the exposure levels of ELF magnetic fields. Precautions should, therefore, be taken either to reduce leakage or minimize the exposed fields. Shielding techniques should be used to minimize the leakage magnetic fields in such cases.  相似文献   
100.
North Africa is increasingly seen as an important context for understanding modern human evolution and reconstructing biocultural adaptations. The Sahara, in particular, witnessed a fluorescence of hunter‐gatherer settlement at the onset of the Holocene after an extended occupational hiatus. Subsequent subsistence changes through the Holocene are contrary to those documented in other areas where mobile foraging gave way to settled agricultural village life. In North Africa, extractive fishing and hunting was supplanted by cattle and caprine pastoralism under deteriorating climatic conditions. Therefore, the initial stage of food production in North Africa witnessed a likely increase in mobility. However, there are few studies of paleomobility in Early Holocene hunter‐gatherer Saharan populations and the degree of mobility is generally assumed. Here, we present radiogenic strontium isotope ratios from Early Holocene fisher‐forager peoples from the site of Gobero, central Niger, southern Sahara Desert. Data indicate a relatively homogeneous radiogenic strontium isotope signature for this hunter‐gather population with limited variability exhibited throughout the life course or among different individuals. Although the overall signature was local, some variation in the radiogenic strontium isotope data likely reflects transhumance into the nearby Aïr Massif. Data from Gobero were significantly less variable than in other worldwide hunter‐gatherer populations, including those thought to be fairly sedentary. Strontium data from Gobero were also significantly different from contemporaneous sites in southwestern Libya. These patterns are discussed with respect to archaeological models of community organization and technological evolution. Am J Phys Anthropol 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
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