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In this paper we describe a theoretical approach for decentralized data management in sentinel community nutritional surveillance systems for timely warning and intervention, by using customized computer programs. By making the data available at lower levels first, the decentralized data management system builds the institutional capacity at regional, level and allows rapid and appropriate action by decision-makers. In addition, it facilitates the flow of information and strengthens the involvement of field staff. Reports from field experiences should further demonstrate the feasibility, efficacy, costs and benefits of customized data management computer programs.  相似文献   
2.
The recent growth of interest in sustainable development has led to the incorporation of the concept into policy making at a variety of scales. In all cases particular emphasis is placed upon the local scale as the focus for the implementation of policy and initiatives and especially upon local authorities as the major contributor to this process. There has been little assessment, however, of the extent to which local authorities either can, or are, undertaking such initiatives. This paper examines: the potential role that local authorities can play in integrating economic development and the environment; the forms of response and initiatives that are currently in place, drawing upon survey evidence from urban local authorities in England and Wales; and some of the limits to local authority action.  相似文献   
3.
Abstract:  Limestone (karst) outcrops in Southeast Asia are rich in land snails. Certain groups of land snails, in particular Prosobranchia species, are restricted to limestone and show a high degree of short-range endemism. Karst habitats are, however, seriously degraded by quarrying, logging, agriculture, and burning. The effect of these disturbances on land snail fauna is unknown, so we studied paired primary and secondary forest localities on six separate limestone hills in Sabah, Malaysian Borneo. Land snails were sampled with a standard protocol and identified to species level. More than 16,000 individuals, belonging to 74 species, were recorded. In most sites, snail diversities did not differ between disturbed and undisturbed plots. However, pulmonate snails were significantly more abundant at disturbed localities than prosobranch snails, whereas abundances for both groups were similar at undisturbed sites. Because Prosobranchia contain many site-endemic species, our findings suggest that continued exposure to these disturbances will eventually lead to extinctions in this group.  相似文献   
4.
This study was conducted to examine adsorption of pesticides bifenthrin, carbosulfan, λ-cyhalothrin, cypermethrin, endosulfan, parathion methyl, monocrotophos and 4-nitrophenol by sandy clay loam (S.C.L) and sandy loam (S.L) soils (with varying organic content). There was no significant difference between the observed soil water partitioning coefficient values (K d) derived from linear and nonlinear Freundlich isotherms. Adsorption of pesticides on S.C.L soils was higher than those on S.L soils. K d values showed significant correlations (r 2?=?0.8???0.99 and 0.65???0.97) with soil organic carbon content (OC) and weak correlations (r 2?=?0.2???0.29 and 0.1???0.18) with clay contents of S.C.L and S.L soil at p?≤?0.05, respectively for all pesticides (except monocrotophos). Observed K oc values (soil-water partitioning constants based on the organic C fraction of the soil) were in accordance with the literature values of Wauchope and Tomlin with a maximum deviation of less than 0.5 log units. Ten Quantitative Property-Property Relationships (QPPR) among water solubility, n-octanol water coefficient (K ow) and K oc were proposed for studied pesticides except monocrotophos. The models were considered acceptable when predicted-observed difference for log?K ow and log?K oc were ≤?0.3 and ≤?0.5?log units, respectively, during the validation procedure. This work indicates that the log?K oc derived from the log Kow, from some of existing relationships, may be a fair predictor where observed values (i.e., K d and K oc) are not available. Furthermore, predicted leaching potential by groundwater ubiquity scores (GUS) equation was solved by using observed K oc values and literature reported half lives of pesticides. GUS ranked the mobility of nonvolatile compounds i.e., bifenthrin, λ-cyhalothrin, cypermethrin and endosulfan extremely low; methyl parathion very low; 4-nitrophenol low; carbofuran and monocrotophos very high in S.C.L and S.L soils, respectively. Results discussed in this paper provide background to prioritize pesticides or chemical groups that should be evaluated under field conditions with regard to their leaching potential to groundwater in arid climates.  相似文献   
5.
This paper presents the findings of two 'green pricing' studies conducted to evaluate public support of utilities' investments in renewable energy technologies. These studies compared hypothetical WTP statements with actual payment commitments. The results of these studies indicate that the CVM can be an accurate indicator of an individual's WTP, but that it is an unreliable predictor of which individuals will actually pay. This has important implications for aggregating mean WTP estimates of the value of environmental benefits. It also suggests that market simulations can be useful for predicting programme participation rates when voluntary donations are used as a payment vehicle.  相似文献   
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