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201.
Diabetes accelerates the aging process and leads to complications that include blindness, renal failure, nerve damage, stroke, and cardiovascular disease. It has been hypothesized that high plasma glucose concentrations are responsible for increased mitochondrial free radical production and subsequent inactivation of glyceraldehyde phosphate dehydrogenase (GAPDH) in vascular endothelial cells and other cells implicated in these complications. As a result of the decreased ability of GAPDH to process upstream metabolites, three pathways of metabolic damage are activated, which include the advanced glycation end-product formation pathway, the protein kinase C pathway, and the hexosamine pathway. All three pathways have been implicated in abnormal cell signaling in diabetes. A group of German and U.S. scientists has now found that treating diabetic rats with high doses of benfotiamine, a lipid-soluble form of vitamin B1, can prevent diabetic retinopathy and all three forms of metabolic damage by stimulating transketolase activity and thus diverting excess metabolites toward the pentose pathway. Although vitamin B1 is available over the counter, the researchers at this time do not advocate self-treatment without further clinical data.  相似文献   
202.
In this case study, we describe the symptoms, neurological exam, neuropsychological test results, and brain pathology of a man who died with Huntington's disease (HD). HD is a rare neurodegenerative disease. Like other movement disorders involving the basal ganglia, HD affects motor, cognitive, and psychiatric functioning. The disease follows an autosomal dominant pattern of inheritance, with onset of symptoms most commonly occurring in the late 30s or early 40s, as in this patient. HD is caused by an unstable expansion of the trinucleotide CAG, coding for glutamine, on chromosome 4. Despite knowledge of the gene mutation responsible for HD, no definitive treatment is currently available to slow or halt progression of the disease. However, symptomatic treatment can significantly improve the quality of life for patients with HD.  相似文献   
203.
An industry specific rehabilitation programme was developed to cater for the special requirements of the New Zealand logging industry. The aims of the rehabilitation programme were to: reduce the amount of time lost due to injury, reduce the number of lost time injuries, and overall, to reduce the direct costs associated with logging injuries. The programme was field-tested on a logging company. The rehabilitation programme was effective for reducing the average amount of time lost due to injury and also for reducing the cost of the injuries. Although there were a number of factors that may have had an impact upon these results, this research provides evidence that this rehabilitation programme was effective for reducing the severity and cost of injury to the New Zealand logging industry.  相似文献   
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The role of human and organizational factors in predicting accidents and incidents has become of major interest to the UK offshore oil and gas industry. Some of these factors had been measured in an earlier study focusing on the role of risk perception in determining accident involvement. The current study sought to extend the methodology by focusing on perceptions of organizational factors that could have an impact on safety. A self-report questionnaire was developed and distributed to 11 installations operating on the UK Continental Shelf. A total of 722 were returned (33% response rate) from a representative sample of the offshore workforce on these installations. The study investigated the underlying structure and content of offshore employees' attitudes to safety, feelings of safety and satisfaction with safety measures. Correlations and step-wise regression analysis were used to test the relationships between measures. The results suggest that 'unsafe' behaviour is the 'best' predictor of accidents/near misses as measured by self-report data and that unsafe behaviour is, in turn, driven by perceptions of pressure for production.  相似文献   
206.
Human-dominated ecosystems such as in South Florida's Everglades region are greatly affected by societal actions and choices, and efforts to restore degraded ecosystems must take into account the societal drivers of ecosystem change. A conceptual model of societal-ecological interactions within the region illustrates connections between major societal drivers, such as water management and land use, and ecological stressors, such as loss of habitat and nutrient loading. Using the conceptual model as an initial guide for discussion, examination of a restoration scenario for the region shows that social and economic effects from activities proposed in a restoration scenario will likely affect most sectors of South Florida. Political effects from changing land and water management practices likely will be significant, as will the physical effects of changing water structures and management practices. Conceptual models such as this can aid in the initial stages of ecosystem restoration discussions and can assist in planning for subsequent social science evaluations of specific societal impacts of actual proposed governmental restoration alternatives. In crafting restoration scenarios, local, regional, and national decision makers can use conceptual models such as this to help broaden the early considerations of how possible future changes in societal drivers, including management choices, will change ecological stressors that affect ecosystem health.  相似文献   
207.
Mark Nord 《Rural sociology》2000,65(1):104-125
Abstract Rural‐urban differences in the association of food insecurity and hunger with income suggest that the cost of living is substantially lower in rural than in urban areas. This implies that the official poverty rate overstates rural economic hardship compared with that in urban areas. Geographic differences in cost of living implied by the association between food insecurity and income provide some validation of the cost of housing adjustment proposed by the National Academy of Sciences (NAS) panel on improving the measurement of poverty, but suggest that the NAS adjustment generally overcorrects for cost of living and would be seriously problematic in some regions.  相似文献   
208.
209.
Input‐output analysis is frequently used in studies of large‐scale weather‐related (e.g., Hurricanes and flooding) disruption of a regional economy. The economy after a sudden catastrophe shows a multitude of imbalances with respect to demand and production and may take months or years to recover. However, there is no consensus about how the economy recovers. This article presents a theoretical route map for imbalanced economic recovery called dynamic inequalities. Subsequently, it is applied to a hypothetical postdisaster economic scenario of flooding in London around the year 2020 to assess the influence of future shocks to a regional economy and suggest adaptation measures. Economic projections are produced by a macro econometric model and used as baseline conditions. The results suggest that London's economy would recover over approximately 70 months by applying a proportional rationing scheme under the assumption of initial 50% labor loss (with full recovery in six months), 40% initial loss to service sectors, and 10–30% initial loss to other sectors. The results also suggest that imbalance will be the norm during the postdisaster period of economic recovery even though balance may occur temporarily. Model sensitivity analysis suggests that a proportional rationing scheme may be an effective strategy to apply during postdisaster economic reconstruction, and that policies in transportation recovery and in health care are essential for effective postdisaster economic recovery.  相似文献   
210.
Protecting riparian corridors is a commonly applied environmental policy in urban landscapes. However, empirical data demonstrating their efficacy for biodiversity conservation outcomes is scarce. In this study we investigated whether riparian corridor width influences the diversity and community structure of ant (Hymenoptera: Formicidae) and vascular plant assemblages therein. Eighteen corridors of differing widths were selected from within the Ku-ring-gai Local Government Area, Sydney Australia. Ants were sampled using pitfall traps positioned within rectangular vegetation transects (30 × 10 m). Both ant and plant species richness, when standardised for sampling effort, were unrelated to riparian corridor width. However, significant compositional differences between sites were evident with increased width up to ~50 m. Narrow corridors contained greater abundances of opportunistic ant species and higher proportions of exotic plants. We interpret this to be the result of the greater disturbance/edge influence derived from adjacent upland urban environments. Site beta diversity did not increase with corridor width, suggesting that the exclusion of novel upslope habitats in narrow riparian corridors is not a significant cause of community assemblage modification at these sites. To minimise the impact of deleterious edge effects on ant fauna, environmental managers should seek to retain riparian corridors wider than ~50 m. However, we observed substantial between-site variability of biotic assemblages, irrespective of corridor width. Therefore we recommend that environmental management practice needs to take a catchment-wide approach and consider other parameters that may contribute to riparian health so as to optimise the protection of riparian biodiversity.  相似文献   
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