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Introduction. Musculoskeletal symptoms related to using traditional computer workstations are common. Quantitative methods for measuring muscle stress and strain are needed to improve ergonomics of workstations. We hypothesize that infrared thermography (IRT) is suited for this purpose. Methods. This hypothesis was evaluated by estimating muscle activity in upright and traditional working postures with IRT and surface electromyography (sEMG). IRT and sEMG measurements were conducted in 14 female participants with both working postures. First, measurements with the traditional posture were performed. Later, participants had 1?month to adjust to the upright working posture before repeating the measurements. IRT images were acquired before and after a full working day, with sEMG recordings being conducted throughout the measurement days. Participants evaluated their neck pain severity using neck disability index (NDI) questionnaires before the first and after the second measurement day. Results. Spatial variation in upper back temperature was higher (p?=?0.008) when working in traditional posture and the upright working posture reduced (p?p?=?0.003) after working in the upright posture. Conclusion. IRT was found suitable for evaluating muscle activity and upright working posture to reduce the NDI and muscle activity in the upper back.  相似文献   
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Dependence on forest resources and tropical deforestation in Ghana   总被引:1,自引:0,他引:1  
In Ghana, forests provide many products on which the local population subsists. However, these resources are depleting due to a variety of factors including agricultural expansion and over-exploitation of forest resources. This paper presents an analysis of the level of local dependence on forest resources and its implications for forest management in Ghana. The paper also outlines the causes of continuing deforestation in the studied region from the perspective of the local residents and discusses what role they could play in addressing the problem. The aim is to share more light on the current causes of deforestation and make suggestions for improved community-based forest management practices that could help to reduce deforestation. Primary data was collected through personal interviews and focus group discussions with 431 household heads randomly selected from three Forest Districts in Ghana. The survey showed that income from agriculture constituted 60% of the average total rural household income. Forest income provided 38% of total household income, and off-farm income 2%. The four most highly ranked causes of deforestation are poverty-driven agriculture, lack of alternative rural wage employment other than farming, household population levels, and conflict in traditional land practices. This shows a shift in the view of local people who in the past were quick to blame logging companies and government policies for deforestation. The majority of the respondents depended on wild animals like snail, bush meat, wild honey and wild and cultivated vegetables. Given the reasons for deforestation, much thought needs to go into agroforestry practices (e.g. snail farming, bee keeping, fish farming, and vegetable production) in efforts to reduce deforestation, which are currently less promoted. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
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The role of community-based plantation development in forest rehabilitation and poverty alleviation is a pressing issue for the government of Ghana. In this paper, we present an analysis of the prospects of a community-based plantation using taungya systems and indigenous trees as means to forest rehabilitation and livelihood improvement in Ghana. The project management strategies, communication process and incentive mechanism and their impact on local participation are discussed with the aim to recommending a mechanism through which local farmers can best be involved in rehabilitation of degraded sites in the future in Ghana. Data were collected through a survey using personal interviews of 431 farming households and ten key informants from ten communities living in scattered hamlets in and around forests reserves. The results show a high rate of local participation in project tree planting activities. Four years after the project’s initiation, about 250 ha of plantations had been established using twelve priority indigenous and one exotic species and farmers had indicated improvement in their farming practices and availability of food and forest products. Restoring forest quality as a timber resource and associated values, getting money, food stuff and timber and non-timber for domestic use, and having access to fertile land for farming were the top three issues prioritised by respondents as motivational factors for engaging in the project activities. Overall, this project demonstrates that reversing tropical forest degradation is possible. For this we need local involvement in tree domestication combined with activities that addresses livelihood needs and environmental concerns. This case also demonstrates the prospects of utilising indigenous tree species, not only exotic species that dominated tree planting in the past, for plantations and landscape rehabilitation in Ghana. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
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Diastrophic dysplasia, an autosomal recessive disorder, results in severe short-limbed dwarfism, progressive spinal and joint problems, and secondary psychosocial disability. The results of treatments are unsatisfactory. Four pregnant mothers at risk for an affected fetus were studied with an ultrasound scanner at 16 and 19 weeks of gestation. Each mother had a previous child with diastrophic dysplasia. The biparietal distance and the length of the long bones of the extremities were normal in three fetuses, whereas in one fetus there was a 30 per cent shortening of all long bones. The biparietal distance corresponded with the gestational age in all fetuses. In one fetus, diastrophic dysplasia was confirmed by fetoscopy and fetal radiograph at 19 weeks of gestation after the parents had decided to terminate the pregnancy. The skeletal radiograph and autopsy findings of the fetus verified the diagnosis. All other mothers were followed with repeated ultrasound examinations, and they delivered healthy babies. The retrospective follow-up of the four previous pregnancies and of the present one with affected fetuses disclosed that two mothers had had vaginal bleeding, two lymphedema, one abdominal pains, and one mother had had polyhydramnios. These complications were, however, mild and transient, and they could not be regarded as specific for pregnancies with affected fetuses.  相似文献   
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The goal of this work was to study the ability of 18 pesticides to inhibit selective model activities for all major xenobiotic-metabolizing enzymes, namely CYP1A1/2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1 and 3A4. Generally organophosphorus insecticides were the most potent and extensive inhibitors, especially towards CYP1A1/2 (IC50 values of chlorpyrifos, fenitrothion and profenofos ~3 μ M), CYP2B6 (IC50 values of chlorpyrifos and fenitrothion 2.5 μ M), CYP2C8 (fenitrothion 4.3 μ M), CYP2C9 (fenitrothion and malathion 4.8 and 2.5 μ M, respectively), CYP2D6 (chlorpyrifos and phenthoate ~ 3 μ M) and CYP3A4 (chlorpyrifos, fenitrothion and phenthoate 3–4 μ M). Otherwise there were quite considerable differences in potency and extent of inhibition between different organophosphates. Pyrethroids were in general very weak or inactive. Deltamethrin and fenvalerate were potent inhibitors of CYP2D6 (IC50 values of ~ 3 μ M) while lambda-cyhalothrin potently inhibited both CYP2D6 and CYP3A4-mediated activities (IC50's about 3–4 μ M). Some pesticides caused relatively potent inhibitions sporadically (carbendazim, CYP2D6, IC50 = 12 μ M; atrazine, CYP3A4, IC50 = 2.8 μ M; glyphosate, CYP2C9, IC50 = 3.7 μ M; hexaflumuron, IC50 = 6.0 μ M). With the exceptions of alpha-cypermethrin, cypermethrin, isoproturon, carbaryl and abamectin, most pesticides inhibited relatively potently at least one CYP-selective activity, which may have relevance for potential interactions in occupational exposures and for further studies on the CYP-associated metabolism of respective pesticides.  相似文献   
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We studied the indoor penetration of ambient air malodorous sulfur compounds released by pulp mills. The indoor and outdoor concentrations were simultaneously measured with automatic SO2 analyzers. The filtering effect of three different materials connected to a gaseous filter unit was tested during six study periods. The tested materials were Sorbixofil® based on gypsum impregnated by KMnO4 Purafil® based on Al2O3, both absorbing sulfur compounds by oxidation, and carbonized tissue. The periods lasted from 14 to 88 days. The results indicated that malodorous sulfur air pollutants penetrated indoors effectively, but after some delay because the dilution was slow. In a comparison of different filter materials, Purafil® was the most effective, producing low indoor concentrations. The study concludes that people living near pulp mills are exposed to substantial amounts of malodorous air pollutants, both indoors and outdoors. This exposure can be reduced by using gaseous sulfur sensitive filter materials connected to a controlled ventilation system.  相似文献   
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