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After describing an innovative technology, the close-coupled gasification and cyclonic combustor, this article explores the policy issues that inhibit a superior sustainable solution fromflourishing. Discussion of technology includes defining biomass,explaining what biomass to energy means, what the advantages of biomass to energy are, and why gasification is a superior biomassto energy technology. Specifically the environmental benefits ofalternatives to landspreading of traditional manure management arediscussed, as well as the advantages of gasification versus traditional combustion techniques for high nitrogen fuels. The policy environment is explored, particularly regarding sustainability, manure management, and renewable energy. Artificial, non-sustainable barriers to renewable energy, and the impact of wide jurisdictional variability are discussed. North Carolina is identified as a unique jurisdiction to monitor because of its high volume of livestock manure, and laggard position in renewable energy advocacy. The authors contend that these two positions are unsustainable, and that pressures can beexpected to force the state to modify its renewable energy policies or risk losing market share in livestock production tomore pro-sustainable policy oriented states.  相似文献   
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A case of epignathus, detected prenatally in a 20-week fetus, is described. The pathological features are discussed in relation to the biochemical and ultrasonographic findings.  相似文献   
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An analysis of multiple species of Australian gall-inducing thrips with soldiers reveals a significant negative correlation between the size of gall produced and the reproductive division of labour. This correlation suggests that the evolution of smaller galls limited the available space and feeding sites for the offspring of female soldiers, and was a major factor that led to the evolution of an altruistic caste in the gall-inducers. We argue that high levels of inbreeding by singly mated foundresses and incestuous mating by her soldier offspring are key to this evolutionary relationship because they make the relatedness of a female soldier to her daughters and sisters approximately equal. Evidence that relatedness plays an important role is strengthened by the observation of outbred multiply mated foundresses and unbiased sex ratio of dispersers in Oncothrips waterhousei, and the inference that both gall volume and skew decreased along this lineage.  相似文献   
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An evaluation of the imprecision in dose predictions has been performed using current dose assessment models and present knowledge of the variability or uncertainty in model parameter values. The propagation of parameter uncertainties is demonstrated using a Monte Carlo technique for elemental 131I transported via the pasture-cow-milk-child pathway. The results indicate that when site-specific information is not available the imprecision inherent in the predictions for this pathway is potentially large. Generally, the 99th percentile in thyroid dose for children was predicted to be approximately an order of magnitude greater than the median value. The potential consequences of the imprecision in dose for radiation protection purposes are discussed.  相似文献   
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