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This paper analyzes livelihood change and livelihood sustainability of households in the upland part of the Lembang subwatershed, West Sumatra, in response to changes in the natural resource management context during the last decade. Using the sustainable livelihood framework (SLF), we measured livelihood changes at two separate points in time, 1996 and 2006, and assessed their environmental, economic, social, and institutional sustainability. We found that people with a low income had less access to capital assets than people from middle- and high-income groups. Our analysis revealed, however, that access to capital assets increased over time, and that poor households experienced economic improvement, indicating an overall increase in economic sustainability. Environmental sustainability, however, is threatened by intensive agricultural practices such as high agrochemical input and intensive soil tillage on steep slopes, leading to pollution and soil erosion. Social sustainability is also a matter of concern: while social exclusion has been reduced, income inequity has increased. Institutional sustainability is likely to remain uncertain, as local institutions for natural resource management are still weak, despite the fact that decentralization has been implemented during the last 8 years. External facilitation is needed to improve the livelihood of upland people while, at the same time, enhancing the sustainability of watershed management. Strengthening local institutions, conserving natural resources, and promoting environmentally sound agricultural practices are the three most important policies to be promoted within the watershed.  相似文献   
233.
Particulate matter (PM), along with other air pollutants, pose serious hazards to human health. The Artificial Neural Network (ANN) is a branch of artificial intelligence that has an ability to make accurate predictions. In this article, the authors describe such methods and how historical data on air quality, moisture, wind velocity, and temperature in Shahr‐e Ray City, located at the southern tip of Tehran, was used to train an ANN to provide accurate predictions of PM concentrations. The availability of such predictions can offer significant assistance to those who are working to reduce air pollution.  相似文献   
234.
The aim of this study was to verify that in a hot environment, the subjective state could affect cognitive performance before any increase in core temperature. Eighteen volunteers performed a planning (OTS) and a reaction time task in hot and control environments. Before starting the cognitive assessment, subjects completed the Positive and Negative Affect Schedule (PANAS) and provided subjective measures of thermal comfort and thermal sensation. Our results showed that while simple tasks were not affected, complex cognitive task performance was significantly reduced in the HOT. Furthermore, although subjects responded faster during the complex task (OTS) they took longer to find the correct solution. Within the 15 min of heat exposure, skin temperature (Tskin) significantly increased by ∼3 °C. However, core temperature remained unchanged and there were cortical excitability alterations that could have influenced cognitive performance. Therefore, the increase in Tskin appears to be a sufficient physiological response to alter the subjective state of individuals and impair effective decision-making that could have important consequences in occupational settings.  相似文献   
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Environmental heavy metal contamination is a case of concern for both animal and human health. Studying the fate of metals in plant or animal tissues may provide information on pollution. In the present study, we investigated the possibility to follow the biological fate of chromium and platinum uptake in common garden snails (Helix aspersa), typically accumulating high concentrations of metals from their environment. Chromium and platinum were administered orally to snails in 5 groups (n = 25/group): control, food contaminated by ca. 2.5 μg g?1 and 19 μg g?1 chromium and 2.5 μg g?1 and 25 μg g?1 platinum, for 8 weeks. Following exposure, surviving snails were sacrificed, shell and remaining tissue investigated by ICP-MS, and shell, midgut gland and mantle by nano-secondary ion mass-spectrometry (Nano-SIMS). 12C14N-normalized platinum and 40Ca-normalized chromium measurements indicated highest enrichments in cellular vesicles of the midgut gland, and lower concentrations in mantle and shell, with significantly higher platinum and chromium concentrations in the 2 exposure groups vs. control (P < 0.05), with somewhat differing distribution patterns for chromium and platinum. Comparable results were obtained by ICP-MS, with both chromium and platinum fed snails showing drastically elevated concentrations of metals in shell (up to 78 and 122 μg g?1 dw platinum and chromium, respectively) and in other tissues (up to 200 and 1125 μg g?1 dw platinum and chromium, respectively). Nano-SIMS allowed for semi-quantitative comparison of metal fate in snail tissues, making this an interesting technique for future studies in the area of environmental pollution.  相似文献   
238.
Concentrations of polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were determined in two fish species, mullet (Mugil cephalus) and sea bass (Dicentrarchus labrax), collected from Bizerte Lagoon and the Mediterranean Sea. In all samples, PCBs were found in higher concentrations than OCPs. The highest concentrations of OCPs and PCBs were found in sea bass, and in Bizerte Lagoon. Concentrations of DDTs and PCBs detected in this study were generally comparable or slightly higher than those found in studies from other Mediterranean and non-Mediterranean regions subject to a high anthropogenic impact. ∑PCBs, ∑HCHs and HCB levels were negatively correlated with lipid content, while no such correlation was seen for ∑DDTs. A significant correlation between levels and length and between levels and weight existed only for ∑PCBs. The daily intake of PCBs and OCPs ingested by people living in Bizerte through the studied fish species was estimated and compared with those observed in other areas.  相似文献   
239.
A decision support system (DSS) involving an approach for predicting wheat leaf rust (WLR) infection and progress based on night weather variables (i.e., air temperature, relative humidity, and rainfall) and a mechanistic model for leaf emergence and development simulation (i.e., PROCULTURE) was tested in order to schedule fungicide time spray for controlling leaf rust progress in wheat fields. Experiments including a single fungicide treatment based upon the DSS along with double and triple treatment were carried out over the 2007–2009 cropping seasons in four representative Luxembourgish wheat field locations. The study showed that the WLR occurrences and severities differed according to the site, cultivar, and year. We also found out that the single fungicide treatment based on the DSS allowed a good protection of the three upper leaves of susceptible cultivars in fields with predominant WLR occurrences. The harvested grain yield was not significantly different from that of the double and triple fungicide-treated plots (P?<?0.05). Such results could serve as basis or be coupled to cost-effective and environmentally friendly crop management systems in operational context.  相似文献   
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Abstract

Delayed neurotoxic ataxia, similar to that caused by neurotoxic organophosphorous compounds, has been shown to occur in hens after oral administration of Cyanofenphos (O‐ethyl‐O‐Cyanophenyl phenyl phosphonothionate) following either single or repeated oral doses. Axonal and myelin degeneration affecting the long tracts in spinal cord, peripheral nerves and medulla was demonstrated. The distal fibers with large diameters were particularly affected. This finding is a new contribution which has not been previously recorded. It implies that a thorough study of the structure‐activity relationships of phosphonothionates regarding their delayed neurotoxic effect is warranted.  相似文献   
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