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1.
Summary The use of reticulated polyurethane foam as a support material for the immobilization of methanogenic associations and its application to the anaerobic treatment of fine particulate solid wastes was investigated. The colonization of polyurethane support particles in a continuous upflow reactor fed on a mixture of acetate, propionate and butyrate, was both rapid and dense. The combination of rumen microorganisms and colonized support particles in a two-phase digester resulted in an efficient anaerobic decomposition of papermill sludge.  相似文献   
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Intravenous inoculation of a penicillin-resistant, phage type 80/81 staphylococcus caused lethal infection in 8 of 15 untreated monkeys. Daily intragastric administration of 50 mg/kg of triacetyloleandomycin, erythromycin estolate, and erythromycin ethylsuccinate was followed by mortalities of 0 of 16, 3 of 16, and 3 of 10, respectively. At dose levels of 25 and 12.5 mg/kg, none of 7 and 4 of 7 receiving triacetyloleandomycin and erythromycin estolate, respectively, died, as compared to 3 of 4 deaths in controls. In vitro sensitivity data and serum antibacterial levels would suggest that triacetyloleandomycin would be the least effective therapeutically. However, this prediction was not fulfilled in these studies of experimental infections in monkeys wherein triacetyloleandomycin was a very effective antimicrobial agent.  相似文献   
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OBJECTIVES: To investigate the extent of problems in recruiting general practitioners and to determine which practice characteristics affect recruitment--in particular, to see if practices with deprived patients have more recruitment problems. DESIGN: Postal questionnaire survey in August 1995. SUBJECTS: 489 consecutive practices that had advertised for a partner in the BMJ from January to April 1995. MAIN OUTCOME MEASURES: The number of applicants, the practices, satisfaction with their quantity and quality, and whether a successful appointment was made. RESULTS: 442 (90%) practices replied. 262 practices (60%) were not very satisfied or very dissatisfied with the number of applications they received; 15 (3%) received no applications. There was a significant difference in the number of applications received by practices in different NHS regions. The 32 practices with the highest proportions of patients eligible for deprivation payments received a median of five applicants compared with 10 for practices without deprivation. CONCLUSION: There is a widespread problem in recruiting general practitioners. Recruitment is hardest in areas with the greatest health needs.  相似文献   
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OBJECTIVE: To determine the effect of deprivation on variations in general practitioners'' referral rates using the Jarman underprivileged area (UPA(8)) score as a proxy measure. DESIGN: Cross sectional survey of new medical and surgical referrals from general practices to hospitals (determined from hospital activity data). SETTING: All of the 183 general practices in Nottinghamshire and all of the 19 hospitals in Trent region. MAIN OUTCOME MEASURES: The relation between the referral rates per 1000 registered patients and the practice population''s UPA(8) score (calculated on the basis of electoral ward), with adjustment for the number of partners, percentage of patients aged over 65 years, and fundholding status of each practice. RESULTS: There was a significant independent association between deprivation, as measured by the UPA(8) score, and high total referral rates and high medical referral rates (P < 0.0001). The UPA(8) score alone explained 23% of the total variation in total referral rates and 32% of the variation in medical referral rates. On multivariate analysis, where partnership size, fundholding status, and percentage of men and women aged over 65 years were included, the UPA(8) score explained 29% and 35% of the variation in total and medical referral rates respectively. CONCLUSION: Of the variables studied, the UPA(8) score was the strongest predictor of variations in referral rates. This association is most likely to be through a link with morbidity, although it could reflect differences in patients'' perceptions, doctors'' behaviour, or the use and provision of services.  相似文献   
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Infrastructure development can affect avian populations through direct collision mortality. Estimating the exposure of local bird populations to the risk of direct mortality from infrastructure development requires site- and species-specific data, which managers may find difficult to obtain at the scale over which management decisions are made. We quantify the potential exposure of sandhill cranes (Antigone canadensis) to collision with horizontal structures (e.g., transmission lines) within vital wintering grounds of the Middle Rio Grande Valley (MRGV), New Mexico, USA, 2014–2020. Limited maneuverability and visual acuity make sandhill cranes vulnerable to collisions with infrastructure bisecting their flight paths. We used data from 81 global positioning system (GPS)-tagged cranes to estimate the spatially explicit flight height distribution along the MRGV, the passage rate across hypothetical transmission lines, and the resulting exposure rate (exposed passes/crane/day). The exposure rate ranged from 0–0.28 exposed passes/crane/day (median = 0.015) assuming an exposure zone of 7–60 m above ground level, and identified hotspots of potential exposure within the MRGV. Mapped exposure rates can assist in the siting of proposed high-voltage transmission lines, or other infrastructure, to limit effects on sandhill cranes and other avian species at risk of collision. Our approach can be replicated and applied in similar situations where birds are exposed to possible collision with power lines. © 2021 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society.  相似文献   
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Arts education partnerships have become an important means for developing and sustaining school arts programs that engage students, teachers, and communities. Tapping into additional perspectives, resources, and support from arts agencies and postsecondary institutions, arts education partnerships strengthen arts education infrastructure within schools and develop a web of sustainable relationships whereby stakeholders mutually benefit. This article provides a snapshot of an arts education partnership in action that develops creative and cultural competencies in middle school students through a theme-based collaborative project approach. This article informs policy by recommending support for arts education partnerships that develop social and creative capital among schools and postsecondary institutions and within the communities surrounding these institutions.  相似文献   
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Objective: Sedentariness is associated with weight gain and obesity. A treadmill desk is the combination of a standing desk and a treadmill that allow employees to work while walking at low speed. Design and Methods: The hypothesis was that a 1‐year intervention with treadmill desks is associated with an increase in employee daily physical activity (summation of all activity per minute) and a decrease in daily sedentary time (zero activity). Employees (n = 36; 25 women, 11 men) with sedentary jobs (87 ± 27 kg, BMI 29 ± 7 kg/m2, n = 10 Lean BMI < 25 kg/m2, n = 15 Overweight 25 < BMI < 30 kg/m2, n = 11 Obese BMI > 30 kg/m2) volunteered to have their traditional desk replaced with a treadmill desk to promote physical activity for 1 year. Results: Daily physical activity (using accelerometers), work performance, body composition, and blood variables were measured at Baseline and 6 and 12 months after the treadmill desk intervention. Subjects who used the treadmill desk increased daily physical activity from baseline 3,353 ± 1,802 activity units (AU)/day to, at 6 months, 4,460 ± 2,376 AU/day (P < 0.001), and at 12 months, 4,205 ± 2,238 AU/day (P < 0.001). Access to the treadmill desks was associated with significant decreases in daily sedentary time (zero activity) from at baseline 1,020 ± 75 min/day to, at 6 months, 929 ± 84 min/day (P < 0.001), and at 12 months, 978 ± 95 min/day (P < 0.001). For the whole group, weight loss averaged 1.4 ± 3.3 kg (P < 0.05). Weight loss for obese subjects was 2.3 ± 3.5 kg (P < 0.03). Access to the treadmill desks was associated with increased daily physical activity compared to traditional chair‐based desks; their deployment was not associated with altered performance. For the 36 participants, fat mass did not change significantly, however, those who lost weight (n = 22) lost 3.4 ± 5.4 kg (P < 0.001) of fat mass. Weight loss was greatest in people with obesity. Conclusions: Access to treadmill desks may improve the health of office workers without affecting work performance.  相似文献   
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GENERAL NOTES     
Macdonald, M. A. 1980. The ecology of the Fiscal Shrike in Ghana, and a comparison with studies from southern Africa. Ostrich 51:65-74.

The Fiscal Shrike Lanius collaris was studied in southern Ghana in order to compare its ecology there with that in southern Africa. The bird was found mainly in the damper coastal areas and usually in habitats created by man. Feeding behaviour is described. Food consisted mainly of a wide variety of insects. Territories were small at around 0,6 ha. Most nests were built 1,8-2,4 m from the ground, and eggs were laid from December to October. Moult appeared to take place in September to November when breeding activity was low. The normal and maximum clutch was three eggs. At most, 10–17% of clutches produced fledged young. Most losses were probably caused by predators. Two successful broods per pair were reared annually. Post-fledging survival of the young was high, and they remained on the parental territory for 5–7 months. Contrasts between the breeding biology in Ghana and southern Africa may be related to differences in environmental seasonality and perhaps also in the severity of nest losses.  相似文献   
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