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141.
The reproductive and larval biology of the common Antarctic cushion-star Odontaster validus Koehler (Echinodermata: Asteroidea) were studied in a shallow-water population at Signy Island in the maritime Antarctic. The gonad index peaked in April/May, and injection with 1-methyladenine indicated that competence to spawn peaked in May/June. Gastrulae were first detected in May, and maximal water-column larval densities were measured in July. Reproduction was therefore highly seasonal, although not all individuals appeared to spawn each year. The pyloric caeca index increased in summer (typically November to March, but variable between years) and decreased during winter (June to October), suggesting that feeding activity was seasonal. All aspects of biology investigated showed significant interannual variability. Comparison with previous studies in the high Antarctic at McMurdo Sound indicated a similar if more pronounced seasonality at Signy, but the warmer seawater temperatures in the maritime Antarctic (particularly in late winter/early spring from September onwards) resulted in faster larval development at Signy. Received: 21 April 1997 / Accepted: 28 January 1998  相似文献   
142.
Coastal dunes are delicate systems that are under threat from a variety of human and natural influences. Groundwater modelling can provide a better understanding of how these systems operate and can be a useful tool towards the effective management of a coastal dune system, e.g. by identifying strategically important locations for flora and fauna and guiding the planning of management operations through predicting impacts from climatic change, sea level rise and land use management. Most dune systems are small, typically of the size 10–100 km2, compared with inland groundwater systems. Applying conventional groundwater modelling approaches to these small systems presents a number of challenges due to the local scale of the system and the fact that the system boundaries (sea, drains, ponds etc.) are close to the main body of the aquifer. In this paper, two case studies will be presented using different modelling approaches to understand the groundwater balance in two dune systems in the UK. The studies demonstrate that, although conventional hydraulic models can describe the general system behaviour, a fuller understanding of the recharge mechanisms and system boundaries is needed to represent adequately system dynamics of small groundwater systems.  相似文献   
143.
As the United States and other countries move toward a greater reliance on nuclear energy, it becomes increasingly important to characterize the environment around such facilities to protect society, human health, and the environment. This article presents an ecological, multidisciplinary approach to gathering the information needed to establish baselines, site new nuclear facilities, protect existing nuclear facilities and nuclear wastes, improve the basis for emergency planning, devise suitable monitoring schemes to ensure continued protection, provide data to track local and regional response changes, and provide for mitigation, remediation, and decommissioning planning. We suggest that there are five categories of information or data needs: (1) geophysical, sources, fate and transport; (2) biological systems; (3) human health; (4) stakeholder and environmental justice; and (5) societal, economic, and political. All of these categories are influenced by temporal and spatial patterns, vulnerabilities, and global changes. These informational needs are more expansive than the traditional site characterization but encompass a suite of physical, biological, and societal needs to protect all aspects of human health and the environment, not just physical health. We suggest that technical teams be established for each of the major informational categories, with appropriate representation among teams and with a broad involvement of a range of governmental personnel, natural and social scientists, Native Americans, environmental justice communities, and other stakeholders. Although designed for nuclear facilities, the templates and information teams can be adapted for other hazardous facilities. © 2013 Wiley Periodicals, Inc.  相似文献   
144.
Concentrations of polychlorinated biphenyls (PCBs) were determined in wild mussels (Mytilus galloprovincialis) from seven areas of the N-NW Spanish coast, during the period 1991-2009. The studied area is comprised of highly productive ecosystems which support important commercial fishing and shellfishing activities. The seven PCBs indicator congeners recommended by ICES (IUPAC nos. 28, 52, 101, 118, 138, 153 and 180), were analysed by gas chromatography with an electron capture detector (GC-ECD). Lowest average concentrations of PCBs were recorded in Arousa (1.04 μg kg(-1) wet weight), a low populated area with no industry; while the highest levels were found in areas near cities and/or showing a high industrial activity such as: Bilbao Ziérbena (139 μg kg(-1) ww) or A Coru?a (55 μg kg(-1) ww). The hexachlorinated congeners CB153 and CB138 dominated the profiles in all wild mussel populations, although a geographical pattern was found in which the relative contributions of the lower chlorinated congeners were higher in the west coast (Rías of Vigo, Pontevedra and Arousa), which may reflect the occurrence of recent inputs of those compounds in the area. Finally, the application of the Mann-Kendall's test demonstrate the existence of a significant decrease in PCBs levels since 1991 up to 1996 in the studied area, whereas either a slow decrease or stable concentrations were registered over the past decade.  相似文献   
145.
This paper presents results from laboratory studies to measure the methane yield and rate of digestion of reject bananas. These parameters were determined in experiments that took into account the likely configuration of a full-scale plant in the banana growing region of north Queensland. The digestion was conducted in a 200-l reactor using fed-batch operation, relying entirely on the natural microbial consortia on the reject bananas to avoid reliance on external inocula such as sludge, an undesirable material around food packaging facilities. An enrichment culture was first established in a highly buffered 200-l batch digestion unit. The fed-batch digester was then started by exchanging leachate with the mature batch reactor. Under loading conditions of 0.6 kg VS m(-3)d(-1) over 70 days where the average working volume was 160 l, the digester produced 398+/-20 l CH4 kg VS(-1). Increasing the loading rate to 1.6 kg VS m(-3)d(-1) resulted in a reduced methane yield of 210 l CH4 kg VS(-1) over 23 days of operation, with a concomitant accumulation of banana waste in the digester. The leachate at the end of digestion contained over 4000 mg l(-1)K, 200 mg l(-1) N and 75 mg l(-1), levels that exceed acceptable limits for general agricultural irrigation.  相似文献   
146.

Introduction

We studied the relationship between registered nurses' extended work duration with adverse events and errors, including needlestick injuries, work-related injuries, patient falls with injury, nosocomial infections, and medication errors.

Method

Using bivariate and multivariate logistic regression, this secondary analysis of 11,516 registered nurses examined nurse characteristics, work hours, and adverse events and errors.

Results

All of the adverse event and error variables were significantly related to working more than 40 hours in the average week. Medication errors and needlestick injuries had the strongest and most consistent relationships with the work hour and voluntary overtime variables.

Discussion

This study confirms prior findings that increased work hours raise the likelihood of adverse events and errors in healthcare, and further found the same relationship with voluntary overtime.

Impact on Industry

Legislation has focused on mandatory overtime; however, this study demonstrated that voluntary overtime could also negatively impact nurse and patient safety.  相似文献   
147.
Mankind needs to use the resources and opportunities offered by the marine environment while protecting ecological processes and systems. This is the foundation for sustainable development, which can only be achieved by adopting an appropriate management approach. Whether internationally or at a regional scale, successful management of marine ecosystems needs to be based on a scientifically robust approach to monitoring environmental change. Within such a framework, the conservation of marine biological diversity is problematic, as many conventional measures of diversity are not appropriate for measuring the types of change that require management. New indicators are required and in this paper we summarise some of the current methodology being used to derive such indices, which may be used to evaluate the effectiveness of marine stewardship initiatives. Through a series of examples we demonstrate the application of the taxonomic distinctness indicator of biodiversity to marine environmental assessment and its development towards becoming an operational tool.  相似文献   
148.
149.
Innes JM  Clarke A 《Disasters》1985,9(2):149-154
This paper reports the results of a survey of the physical and mental reactions of a group ( N = 72) of members of the South Australian Metropolitan Fire Service (MFS) who were engaged in fighting the bushfires close to Adelaide, 16th-19th February 1983. A questionnaire, designed to elicit reports on both physical and mental reactions to exposure to the fire, as well as perceptions of several measures of social strain and social support, was administered to the firefighters when they came off duty. The results reported show the possible influence of role strain factors in predicting mental reactions, and also demonstrate what may be mediating effects of perceived social support. The paper also discusses methodological problems affecting this and other studies of the reactions of emergency service personnel to disaster.  相似文献   
150.
Since the 1970s, there has been a global proliferation of environmental courses. The types of courses are described, as are the structures, philosophies and objectives of courses which have stood the test of time. Employment of environmental graduates is discussed. The degree in Australian Environmental Studies (AES) from Griffith University is described and discussed with reference to pitfalls described in the literature. In Australia, there has been an increased demand for graduates in the environmental area. The trend in employers has been widening the field of potential recruits by keeping the degree specification broad and using the duty statements in the advertisements to specify the environmental skills and knowledge required. The number of graduates from AES has increased steadily since the course was established, and despite global and national trends of proliferation of environmental courses and graduates, survey results indicated that graduates from AES are professionally employed in a wide range of employment sectors, with female and male graduates being equally successful in obtaining employment.  相似文献   
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