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51.
TL Dassanayake PT Michie AL Jones T Mallard IM Whyte GL Carter 《Traffic injury prevention》2012,13(5):450-457
Background: Central nervous system-depressant (CNS-Ds) drugs can impair cognitive functions and driving. They are also the most common drugs taken in overdose in hospital-treated episodes of self-poisoning. In Australia most of these patients are discharged within 48?h, while they still have possible subclinical drug effects. We aimed to determine whether patients treated for self-poisoning with CNS-Ds are impaired in the Trail-Making Test (TMT, parts A and B), a neuropsychological test that is known to correlate with driving performance. Methods: This study was a conducted from November 2008 to April 2011 in a referral center for poisonings in New South Wales, Australia. One hundred seven patients discharged from the clinical toxicology unit following treatment for self-poisoning of CNS-Ds (benzodiazepines, atypical antipsychotics, or opioids) and a control group of 68 discharged following self-poisoning of non-CNS-depressant drugs (acetaminophen or nonsedating antidepressants) were tested with the TMT (parts A and B). Due to the known association of impaired TMT with driving impairment and increased risk of traffic accidents, performance less than the 10th percentile for age was defined as significant impairment in each part of the TMT. The odds ratio (OR) for impairment in each part was calculated in multivariate logistic regression (MLR) models adjusted for gender, education, IQ, and the presence of a major psychiatric illness. A secondary MLR analysis was conducted only for those patients (78 CNS-D and 54 control group participants) who were directly discharged home, after excluding those who were transferred for further psychiatric care. Results: The odds of impairment in the CNS-D group was 2.8?times that of the control group on the TMT-A (38 [35.5%] vs. 11 [16.2%]: adjusted OR = 2.76, 95% confidence interval [CI]: 1.28-5.97), and 4.6?times on the TMT-B (67 [62.6%] vs. 22 [32.4%]: adjusted OR = 4.63, 95% CI: 2.06-10.42). The results were similar in the subgroup of patients discharged home, and the odds of impairment in the CNS-D group was 3.3?times that of the control group on the TMT-A (25 [32.1%] vs. 7 [13.0%]: adjusted OR = 3.30, 95% CI: 1.28-8.52), and 3.6?times on the TMT-B (46 [59.0%] vs. 17 [31.5%]: adjusted OR = 3.64, 95% CI: 1.44-9.20). TMT-B impairment in the CNS-D group remained significant even after adjusting for TMT-A performance. Conclusions: Patients with CNS-D overdose may have significant impairment in cognitive skills underlying driving at the time of discharge from hospitals. Clinicians should warn these patients that their driving skills might still be impaired, even if they are considered clinically recovered and advise them not to drive during the first 1 to 2?days following discharge. 相似文献
52.
A national framework for monitoring and reporting on environmental sustainability in Canada 总被引:1,自引:0,他引:1
Ian B. Marshall C. A. Scott Smith Corrine J. Selby 《Environmental monitoring and assessment》1996,39(1-3):25-38
In 1991, a collaborative project to revise the terrestrial component of a national ecological framework was undertaken with a wide range of stakeholders. This spatial framework consists of multiple, nested levels of ecological generalization with linkages to existing federal and provincial scientific databases. The broadest level of generalization is the ecozone. Macroclimate, major vegetation types and subcontinental scale physiographic formations constitute the definitive components of these major ecosystems. Ecozones are subdivided into approximately 200 ecoregions which are based on properties like regional physiography, surficial geology, climate, vegetation, soil, water and fauna. The ecozone and ecoregion levels of the framework have been depicted on a national map coverage at 1:7 500 000 scale. Ecoregions have been subdivided into ecodistricts based primarily on landform, parent material, topography, soils, waterbodies and vegetation at a scale (1:2 000 000) useful for environmental resource management, monitoring and modelling activities. Nested within the ecodistricts are the polygons that make up the Soil Landscapes of Canada series of 1:1 000 000 scale soil maps. The framework is supported by an ARC-INFO GIS at Agriculture Canada. The data model allows linkage to associated databases on climate, land use and socio-economic attributes. 相似文献
53.
Ian Moffatt 《国际发展与全球生态学杂志》2013,20(3):237-250
SUMMARY The ethical and social issues of genetically modified crops as reported by the Nuffield Bioethics Committee are summarised. A critique of their findings is presented. It is argued that the apparent benefits are outweighed by the ecological, social and economic costs, and that the yields of some genetically modified crops are poorer when compared to conventional species. Furthermore, the current regulations are far too lax for consumer protection. There is an urgent need for a critical and disinterested review of the scientific basis of the research. 相似文献
54.
Kebede Nigussie Mekonnen Bhagwan Singh Chandravanshi Mesfin Redi-Abshiro Robert Ian McCrindle 《毒物与环境化学》2013,95(10):1501-1515
For the determination of 15 potentially toxic elements (V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Se, Ag, Cd, Sn, Hg, and Pb) in plant and sediment samples of the Akaki River, Ethiopia, inductively coupled plasma–mass spectrometry, inductively coupled plasma–optical emission spectrometry, and a RA-915+ mercury analyzer were applied. Sediment and plant samples were mineralized using a closed-vessel microwave-assisted digestion system. The elemental concentrations varied considerably in plant and sediment samples. The minimum concentration was observed for known toxic elements (As, Hg, and Cd) while the highest concentration was observed for the elements of relatively low toxicity Zn, Mn, and Fe. The concentration of Cr, Fe, Pb, Zn, and As in Swiss chard surpassed the maximum permissible levels at specific sites. At some of the sites, the sediment quality guidelines are surpassed for Cu, Zn, and Pb. 相似文献
55.
Constitutive and induced defenses to herbivory in above- and belowground plant tissues 总被引:3,自引:0,他引:3
A recent surge in attention devoted to the ecology of soil biota has prompted interest in quantifying similarities and differences between interactions occurring in above- and belowground communities. Furthermore, linkages that interconnect the dynamics of these two spatially distinct ecosystems are increasingly documented. We use a similar approach in the context of understanding plant defenses to herbivory, including how they are allocated between leaves and roots (constitutive defenses), and potential cross-system linkages (induced defenses). To explore these issues we utilized three different empirical approaches. First, we manipulated foliar and root herbivory on tobacco (Nicotiana tabacum) and measured changes in the secondary chemistry of above- and belowground tissues. Second, we reviewed published studies that compared levels of secondary chemistry between leaves and roots to determine how plants distribute putative defense chemicals across the above- and belowground systems. Last, we used meta-analysis to quantify the impact of induced responses across plant tissue types. In the tobacco system, leaf-chewing insects strongly induced higher levels of secondary metabolites in leaves but had no impact on root chemistry. Nematode root herbivores, however, elicited changes in both leaves and roots. Virtually all secondary chemicals measured were elevated in nematode-induced galls, whereas the impact of root herbivory on foliar chemistry was highly variable and depended on where chemicals were produced within the plant. Importantly, nematodes interfered with aboveground metabolites that have biosynthetic sites located in roots (e.g., nicotine) but had the opposite effect (i.e., nematodes elevated foliar expression) on chemicals produced in shoots (e.g., phenolics and terpenoids). Results from our literature review suggest that, overall, constitutive defense levels are extremely similar when comparing leaves with roots, although certain chemical classes (e.g., alkaloids, glucosinolates) are differentially allocated between above- and belowground parts. Based on a meta-analysis of induced defense studies we conclude that: (1) foliar induction generates strong responses in leaves, but much weaker responses in roots, and (2) root induction elicits responses of equal magnitude in both leaves and roots. We discuss the importance of this asymmetry and the paradox of cross-system induction in relation to optimal defense theory and interactions between above- and belowground herbivory. 相似文献
56.
Ian Calder Ashvin Gosain M. S. Rama Mohan Rao Charles Batchelor M. Snehalatha Emma Bishop 《Environment, Development and Sustainability》2008,10(4):537-557
This paper recommends a revision of watershed development policy in India in relation to the planning of development interventions
involving agricultural intensification and rainwater harvesting following biophysical and societal impact studies carried
out on two watershed development projects in Karnataka. A need for changes in policy has arisen in response to progressive
catchments closure at the basin level and declining volumes of water flowing into village level reservoirs (known locally
as tanks). Flow reductions have occurred largely as a result of increased agricultural intensification over the past 10–15 years.
Field levelling, field bund construction, soil water conservation measures, farm ponds, the increase in areas under horticulture
and forestry and the increased abstraction and use of groundwater for irrigation are all contributing factors to reduced flows.
Planning methodologies and approaches, which may have been appropriate 20 years ago for planning water harvesting within watershed
development projects, are no longer appropriate today. New planning approaches are required which (1) take account of these
changed flow conditions and (2) are also able to take account of externalities, which occur when actions of some affect the
livelihoods of others who have no control or influence over such activities and which (3) contribute to the maintenance of
agreed minimum downstream flows for environmental and other purposes.
相似文献
Ian CalderEmail: |
57.
Ian M. Robottom 《The Environmentalist》1987,7(4):291-298
Summary In environmental education in this information age, it is particularly important to adopt the approach of enquiring critically into the environmental, educational and social values informing environmental, educational and social actions when and where required, rather than to simply adopt the approach of emphasising the acquisition and retention of information of an alleged universal type — information drawn from the stockpile of objective knowledge collected by others. This paper argues that to achieve this aim, environmental education in an information age requires aparadigm shift in the areas of professional development — a shift from a paradigm of information technology to a paradigm of information critique. A perspective on the form of this paradigm shift in the particular field of professional development in environmental education is the subject of this paper.Dr Ian Robottom is Senior Lecturer in the Curriculum Studies Centre of the School of Education, at Deakin University, Australia. His main interests lie in teacher education, educational enquiry, and environmental education. He conducts an off-campus environmental education course (B.Ed level) for practising teachers studying at a distance, is a member of the Council of the Australian Association for Environmental Education., and Editor of theAustralian Journal of Environmental Education. 相似文献
58.
Peter Wathern Stephen N. Young Ian W. Brown Dawn A. Roberts 《Environmental management》1987,11(1):7-12
The EEC Shellfish Directive is a policy designed to protect and, where necessary, improve the quality of designated shellfish waters. Its implementation within the UK, however, has had no effect upon water quality for two reasons. First, the policy has important defects, having ambiguities concerning public health provisions and lacking designation criteria. Second, UK government has sought to achieve formal compliance, while at the same time ensuring that its full financial impact on public expenditure has been contained. Consequently, only those fisheries which already comply with water quality standards have been designated. Within Wales, one fishery has been designated, while other, commercially more important, but grossly contaminated shellfisheries have not. 相似文献
59.
60.
Applications of in situ agrobiodiversity conservation practices within agricultural production systems have the potential to reduce the risks of agricultural modernisation and enhance sustainable development. The aims and approaches for in situ conservation differ according to the requirements of communities and nations. Approaches to in situ conservation in the decade after the Convention of Biological Diversity are reviewed within the contexts of marginal agricultural systems in Nepal, Turkey and Switzerland. Numerous approaches are currently utilised, including: the informal de facto retention of agrobiodiversity; the provision of state assistance; the marketing of agrobiodiversity products; the use of technological innovations to develop local diversity; the establishment of conservation reserves; community assistance programmes and the raising of awareness of the issue amongst all sectors of societies. Emerging complementary in situ approaches applicable in the rural margins suggest a framework for effectively conserving agrobiodiversity by working with local people. 相似文献