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91.
92.
Good quality fish sauce was produced from anchovies (Stolephorus spp.) that had been allowed to autolyse at pH 4 and low salt concentration. After an initial phase of rapid autolysis, the samples were neutralised, and salt was added to the normal level (250 g kg?1) before the fish sauce was separated by suction. By this method fish sauce with acceptable flavour could be produced after 2 months, whereas the normal production time is more than 6 months. This rapidly-produced fish sauce had a lower level of volatile base and acid, and a better balanced composition of essential amino acids than a first grade commercial fish sauce.  相似文献   
93.
This paper presents Reinforcement Learning (RL) approaches to Economic Dispatch problem. In this paper, formulation of Economic Dispatch as a multi stage decision making problem is carried out, then two variants of RL algorithms are presented. A third algorithm which takes into consideration the transmission losses is also explained. Efficiency and flexibility of the proposed algorithms are demonstrated through different representative systems: a three generator system with given generation cost table, IEEE 30 bus system with quadratic cost functions, 10 generator system having piecewise quadratic cost functions and a 20 generator system considering transmission losses. A comparison of the computation times of different algorithms is also carried out.  相似文献   
94.
Reactive absorption using aqueous amine solutions is the technically most feasible retrofit option for the separation of CO2 from flue gases. Frequently discussed issues are the realization of a cost‐effective increase in efficiency in the sophisticated overall absorption process and the minimization of the energy demand for solvent regeneration under operating conditions. However, the influence of degradation phenomena on capacity and energy efficiency during the absorption‐regeneration cycles using blended monoethanolamine solutions has been less considered so far. The decrease in capacity depends in particular on time, temperature, O2‐ and SO2 concentration in the flue gas and has to be considered in plant design. Addition of degradation inhibitors decreases the energy requirements.  相似文献   
95.
With the advent of powerful computers, simulation studies are becoming an important tool in statistical methodology research. However, computer simulations of a specific process are only as good as our understanding of the underlying mechanisms. An attractive supplement to simulations is the use of plasmode datasets. Plasmodes are data sets that are generated by natural biologic processes, under experimental conditions that allow some aspect of the truth to be known. The benefit of the plasmode approach is that the data are generated through completely natural processes, thus circumventing the common concern of the realism and accuracy of computer simulated data. The estimation of admixture, or the proportion of an individual’s genome that originates from different founding populations, is a particularly difficult research endeavor that is well suited to the use of plasmodes. Current methods have been tested with simulations of complex populations where the underlying mechanisms such as the rate and distribution of recombination are not well understood. To demonstrate the utility of this method, data derived from mouse crosses is used to evaluate the effectiveness of several admixture estimation methodologies. Each cross shares a common founding population so that the ancestry proportion for each individual is known, allowing for the comparison of true and estimated individual admixture values. Analysis shows that the different estimation methodologies (Structure, AdmixMap and FRAPPE) examined all perform well with simple datasets. However, the performance of the estimation methodologies varied greatly when applied to a plasmode consisting of three founding populations. The results of these examples illustrate the utility of plasmodes in the evaluation of statistical genetics methodologies.  相似文献   
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PURPOSE: Pseudorabies virus (PRV) is a useful tool for mapping the control circuitry of the spinal cord. In the process of mapping CNS regulatory pathways for the lower urinary tract, a hemorrhagic change in the bladder was observed that was not overtly evident in other pelvic organs. The relationship between the appearance of hemorrhagic changes in the bladder and the evolution of PRV induced changes in the spinal cord was therefore explored. MATERIALS AND METHODS: Sprague-Dawley rats were injected with PRV into the ACD tail-muscle. Bladder and CNS fixation were achieved by transcardial perfusion with formaldehyde. Multi-level sections were obtained from T8 through S4. Fixed tissue was stained and evaluated by light microscopy. Immunohistochemical stains were carried out for PRV and iNOS on spinal cord tissue. We were therefore able to evaluate the relationship between the manifestation of the hemorrhagic cystitis, appearance of the PRV in the spinal cord and evidence of CNS inflammation. RESULTS: The evolution of hemorrhagic cystitis paralleled the evidence of inflammation in the thoraco-lumbar and sacral cord. These bladders contained 5 to 9 ml. of bloody urine (a normal rat bladder contains 1 to 2 ml.). On cystomanometry (CMG) the bladders were acontractile. No PRV could be cultured in the hemorrhagic bladders. The histological changes observed in the bladder represent true inflammation. CONCLUSION: There was no obvious explanation for these changes other than the associated inflammatory changes in the spinal cord. The findings are consistent with the hypothesis that a spinal cord stress, via an unknown metabolic pathway, can result in dramatic, neurogenically mediated changes in the bladder.  相似文献   
99.
Airway hyperresponsiveness leading to subepithelial fibrosis is mediated by inflammatory cells activated by T helper (Th) 2-derived cytokines such as IL-4 and IL-5. By analyzing the phenotype and response of human lung fibroblasts derived from either fetal (ICIG7) or adult (CCL202) tissue as well as from a Th2-type stromal reaction (FPA) to IL-4 and IL-13, we provide evidence that human lung fibroblasts may behave as inflammatory cells upon activation by IL-4 and IL-13. We show that the three types of fibroblasts constitute different populations that display a distinct pattern in cell surface molecule expression and proinflammatory cytokine and chemokine release. All fibroblasts express functional but different IL-4/IL-13 receptors. Thus, while IL-4 receptor (R) alpha and IL-13Ralpha1 chains are present in all the cells, CCL202 and FPA fibroblasts coexpress the IL-13Ralpha2 and the IL-2Rgamma chain, respectively, suggesting the existence of a heterotrimeric receptor (IL-4Ralpha/IL-13Ralpha/IL-2Rgamma) able to bind IL-4 and IL-13. Stimulation with IL-4 or IL-13 triggers in the fibroblasts a differential signal transduction and upregulation in the expression of beta1 integrin and vascular cell adhesion molecule 1 and in the production of IL-6 and monocyte chemoattractant protein 1, two inflammatory cytokines important in the pathogenesis of allergic inflammation. Our results suggest that when activated by IL-4 and IL-13, different subsets of lung fibroblasts may act as effector cells not only in the pathogenesis of asthma but also in lung remodeling processes. They may also differentially contribute to trigger and maintain the recruitment, homing, and activation of inflammatory cells.  相似文献   
100.
We report on the noninvasive measurement of temperature, i.e., self-heating effects, in active AlGaN/GaN HFETs grown on sapphire and SiC substrates. Micro-Raman spectroscopy was used to produce temperature maps with ≈1 μm spatial resolution and a temperature accuracy of better than 10°C. Significant temperature rises up to 180°C were measured in the device gate-drain opening. Results from a three-dimensional (3-D) heat dissipation model are in reasonably good agreement with the experimental data. Comparison of devices fabricated on sapphire and SiC substrates indicated that the SiC substrate devices had ~5 times lower thermal resistance  相似文献   
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