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131.
Two novel techniques are presented in this study which together aim to provide a system able to determine the renewable energy potential of mixed waste materials. An image analysis tool was applied to two waste samples prepared using known quantities of source-segregated recyclable materials. The technique was used to determine the composition of the wastes, where through the use of waste component properties the biogenic content of the samples was calculated. The percentage renewable energy determined by image analysis for each sample was accurate to within 5% of the actual values calculated. Microwave-based multiple-point imaging (AutoHarvest) was used to demonstrate the ability of such a technique to determine the moisture content of mixed samples. This proof-of-concept experiment was shown to produce moisture measurement accurate to within 10%. Overall, the image analysis tool was able to determine the renewable energy potential of the mixed samples, and the AutoHarvest should enable the net calorific value calculations through the provision of moisture content measurements. The proposed system is suitable for combustion facilities, and enables the operator to understand the renewable energy potential of the waste prior to combustion.  相似文献   
132.
A simple model allows rapid comparison of typical baseline and policy scenarios which might be considered under international programs to avoid CO2 emissions caused by forest clearing, such as REDD (Reducing Emissions from Deforestation and Forest Degradation). These tests of REDD policy scenarios can also include CO2 stored in forest products. The value of avoided emissions can also be determined if expected carbon prices, constant or varying, are included. The paper discusses simple illustrative example comparisons as well as possible feedback effects within larger scale setting of CO2 offset availability, CO2 price and emissions reductions.  相似文献   
133.
Reproductive carrier screening started in some countries in the 1970s for hemoglobinopathies and Tay-Sachs disease. Cystic fibrosis carrier screening became possible in the late 1980s and with technical advances, screening of an ever increasing number of genes has become possible. The goal of carrier screening is to inform people about their risk of having children with autosomal recessive and X-linked recessive disorders, to allow for informed decision making about reproductive options. The consequence may be a decrease in the birth prevalence of these conditions, which has occurred in several countries for some conditions. Different programs target different groups (high school, premarital, couples before conception, couples attending fertility clinics, and pregnant women) as does the governance structure (public health initiative and user pays). Ancestry-based offers of screening are being replaced by expanded carrier screening panels with multiple genes that is independent of ancestry. This review describes screening in Australia, Cyprus, Israel, Italy, Malaysia, the Netherlands, Saudi Arabia, the United Kingdom, and the United States. It provides an insight into the enormous variability in how reproductive carrier screening is offered across the globe. This largely relates to geographical variation in carrier frequencies of genetic conditions and local health care, financial, cultural, and religious factors.  相似文献   
134.
The Peto test is the standard method of analysis used in carcinogenicity studies to compare tumor incidence in groups of animals. It assumes that tumors are either instantly fatal or have no effect on mortality and requires a judgement of the lethality of each tumor. To avoid this requirement, parametric multi-state models have been proposed. In addition these allow estimation of tumor onset and mortality rates. This paper considers two such models and presents a modification. It is shown that the modified models provide a better fit to carcinogenicity data and simulated data are used to show that the modified models provide a modest increase in test power relative to the Peto test.  相似文献   
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The most effective methods for virus detection in food and environmental samples are those based on nucleic acid amplification. Complex methods must be applied by the analyst in order to control for false negative results of virus detection assays in those samples that may be contaminated by virus concentrations above the detection level. The verification of analytical results is a necessity and this depends on using an appropriate suite of controls to monitor the efficacy of the critical steps in the method and allow correct result interpretations to be made. We describe the suite of controls necessary for analysing food and environmental samples for the presence of enteric viruses by nucleic acid amplification-based methods. To exclude false negative and positive interpretations of results, the inclusion of this suite of controls will be essential when considering incorporating monitoring of viruses in food or environmental safety management plans.  相似文献   
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Countryside strategies, particularly for nature conservation, are part of a growth in non‐statutory strategic planning. They are largely integrative, and set the context for, and are able to cover subjects normally beyond the scope of, statutory development plans. Specifically for nature conservation, this paper summarizes the limitations of policies in structure plans and reviews four countryside strategies to assess the extent to which they overcome these limitations. Whilst providing a renewed focus for nature conservation, such strategies lack information and guidance in assisting plan formulation, are not accountable, have problems in their adoptability and lack the resources for implementation.  相似文献   
140.
Access opportunities for outdoor recreation in New Zealand and England and Wales are classified according to their conformity with collective, citizenship or exclusion rights and their degrees of permanence. Alternative criteria for the apportionment of access rights are considered in the context of this classification. Different criteria for rights apportionment are found to be appropriate according to different circumstances in the context of pluralist provision. Policy developments in New Zealand are compared with those in England. After 150 years of a dominance of collective rights in New Zealand current policy is shifting provision towards exclusionary rights. In England, there is a policy shift in the other direction, towards collective rights. Lessons for the development of collective rights in England are drawn from the New Zealand experience in relation to styles of governance, public preferences, public cost, insurance liability and the potential of markets.  相似文献   
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