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81.
For improving sludge digestion and biogas recovery, a new anaerobic digestion process combined with ozonation was tested at a full-scale unit for 2 years and its performance was compared with a simultaneously operated conventional anaerobic digestion process. The new process requires two essential modifications, which includes ozonation for enhancing the biological degradability of sludge organics and concentrating of solids in the digester through a solid/liquid separation for extension of SRT. These modifications resulted in high VSS degradation efficiency of ca. 88%, as much as 1.3 times of methane production and more than 70% reduction in dewatered sludge cake production. Owing to accumulation of inorganic solids in the digested sludge, water content of the dewatered sludge cake also reduced from 80% to 68%. An energy analysis suggested that no supplemental fuel was necessary for the subsequent incineration of the cake from the new process scheme. The process is suitable to apply to a low-loaded anaerobic digestion tank, where power production is used.  相似文献   
82.
This paper analyses communications between statistical methodology and applied statistics in terms of the similarity and dissimilarity in their authorship and citation patterns, and further the communication distance between them in terms of mutual citation and the time lag therein. Hypotheses are presented on their difference and distance and are verified for data from the Journal of the Royal Statistical Society, the oldest statistical society in the world. The data analysis reveals that they are indeed different and distant each other to a certain extent but less distinctly than initially conjectured in the hypotheses.  相似文献   
83.
This study used Complier Average Causal Effect analysis (CACE; see G. Imbens & D. Rubin, 1997) to examine the impact of an adaptive approach to family intervention in the public schools on rates of substance use and antisocial behavior among students ages 11-17. Students were randomly assigned to a family-centered intervention (N = 998) in 6th grade and offered a multilevel intervention that included (a) a universal classroom-based intervention, (b) the Family Check-Up (selected; T. J. Dishion & K. Kavanagh, 2003), and (c) family management treatment (indicated). All services were voluntary, and approximately 25% of the families engaged in the selected and indicated levels. Participation in the Family Check-Up was predicted by 6th-grade teacher ratings of risk, youth reports of family conflict, and the absence of biological fathers from the youths' primary home. Relative to randomized matched controls, adolescents whose parents engaged in the Family Check-Up exhibited less growth in alcohol, tobacco, and marijuana use and problem behavior during ages 11 through 17, along with decreased risk for substance use diagnoses and police records of arrests by age 18. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Methanosarcina species pyrrolysyl‐tRNA synthetase (PylRS) attaches Pyl to its cognate amber suppressor tRNA. The introduction of two mutations (Y384F and Y306A) into PylRS was previously shown to generate a mutant, designated LysZ‐RS, that was able to attach N‐benzyloxycarbonyl‐L ‐lysine (LysZ) to its cognate tRNA. Despite the potential of LysZ derivatives, further LysZ‐RS engineering has not been performed; consequently, we aimed to generate LysZ‐RS mutants with improved LysZ incorporation activity through in vitro directed evolution. Using a liposome‐based in vitro compartmentalization (IVC) approach, we screened a randomly mutagenized gene library of LysZ‐RS and obtained a mutant that showed increased LysZ incorporation activity both in vitro and in vivo. The ease and high flexibility of liposome‐based IVC should enable the evolution of not only LysZ‐RS that can attach various LysZ derivatives but also of other enzymes involved in protein translation.  相似文献   
85.
Most cases of acute gastroenteritis and foodborne disease are not ascertained by public health surveillance because the ill person does not always seek medical care and submit a stool sample for testing, and the laboratory does not always test for or identify the causative organism. We estimated the total burden of acute gastroenteritis in Miyagi Prefecture, Japan, using data from two 2-week cross-sectional, population-based telephone surveys conducted in 2006 and 2007. To estimate the number of acute gastroenteritis illnesses caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Miyagi Prefecture, we determined the number of cases for each pathogen from active laboratory-based surveillance during 2005 to 2006 and adjusted for seeking of medical care and submission of stool specimens by using data from the population-based telephone surveys. Monte Carlo simulation was used to incorporate uncertainty. The prevalence of acute gastroenteritis in the preceding 4 weeks was 3.3% (70 of 2,126) and 3.5% (74 of 2,121) in the winter and summer months, yielding an estimated 44,200 episodes of acute gastroenteritis each year in this region. Among people with acute gastroenteritis, the physician consultation rate was 32.0%, and 10.9% of persons who sought care submitted a stool sample. The estimated numbers of Campylobacter-, Salmonella-, and V. parahaemolyticus -associated episodes of acute gastroenteritis were 1,512, 209, and 100 per 100,000 population per year, respectively, in this region. These estimates are significantly higher than the number of reported cases in surveillance in this region. Cases ascertained from active surveillance were also underrepresented in the present passive surveillance, suggesting that complementary surveillance systems, such as laboratory-based active surveillance in sentinel sites, are needed to monitor food safety in Japan.  相似文献   
86.
The fruit of Viburnum dilatatum Thunb (gamazumi) has been shown to prevent oxidative injury induced by water immersion restraint stress (WIRS) in rats. In this study the effect of gamazumi crude extract (GCE) on antioxidant enzymatic activities in the plasma, liver and stomach of rats with WIRS was investigated to elucidate the mechanism of prevention of oxidative injury. Ulcer formation and lipid peroxidation were inhibited in rats supplied GCE for 2 weeks in comparison with rats supplied water. Although the activities of plasma, hepatic and gastric antioxidant enzymes in rats given water were decreased by WIRS, only slight changes were observed in rats given GCE. There was no difference in enzymatic activities between the water and GCE groups not subjected to WIRS. Furthermore, ferrous ascorbate‐induced oxidation in hepatic homogenate from rats given GCE was inhibited. These results suggest that ingestion of GCE does not induce antioxidant enzymes and that the absorbed antioxidant components of GCE have a direct effect on oxidative injury in the body. Copyright © 2003 Society of Chemical Industry  相似文献   
87.
Qbeta replicase functioning in Escherichia coli is an RNA-dependent RNA polymerase composed of one phage-coded subunit and three host-coded proteins: ribosomal protein S1, and protein elongation factors EF-Tu and EF-Ts. Qbeta replicase lacking ribosomal protein S1 (alpha-less replicase) is capable of replicating some small RNAs. We attempted to create functional alpha-less replicase by co-expression of the mRNAs that code for the subunits of alpha-less replicase in a rabbit reticulocyte cell-free translation system. Replicase activity, however, could not be detected when both EF-Tu and EF-Ts were co-expressed with the phage-coded subunit. On the other hand, active alpha-less replicase was obtained when an EF-Ts-EF-Tu fusion protein was co-expressed with the phage-coded subunit. Consequently, we succeeded in generating genetically engineered active alpha-less Qbeta replicase which functions in a eukaryotic cell-free system.  相似文献   
88.
Abstract— An external driving circuit that has realized long lifetime, power‐consumption control, and peak luminance for organic light‐emitting diode (OLED) displays have been developed. This circuit realizes an effective method for constant‐anode‐voltage (CV) driving refered to as clamped inverter (CI) driving. The feature of CV driving is to achieve low‐power consumption compared with constant‐anode‐current (CC) driving and to control the power consumption and peak luminance according to the image because display luminance can be easily changed by controlling the anode voltage. On the other hand, CV driving has the problem that luminance deterioration appears to be serious compared with that of CC driving because the current of the OLED element decreases according to usage time. To cope with this, a lifetime compensation circuit that has increased the anode voltage so that it compensates for the luminance deterioration has been developed. This circuit can compensate not only the decrease in current but also the decrease in luminance at a constant current that CC driving cannot. However, increasing the anode voltage causes an increase in stress on the OLED element. The influence of stress on OLED lifetime was verified. As a result, it was confirmed that this circuit can extend the lifetime by 32% even if the anode voltage is increased, causing stress on the OLED structure.  相似文献   
89.
解释了为什么以利润为目的的公司参与标准化活动和特别关注标准与专利的关系,并从经济学角度,使用反公共的悲剧和跨越式发展的概念分析了这个问题.反公共的悲剧解释了为什么公司交叉授权他们的专利许可以及为什么标准化组织的专利政策包含交叉授权.跨越式发展解释了为什么拥有为实施标准的必要专利的公司将他们的专利许可授予没有相关专利的公司.通过向外授予专利许可,公司在短期内可以获得经济利益,在长期可以获得影响市场发展的战略机会,并为民营公司提供一些建议.  相似文献   
90.
A novel Ca2+/calmodulin-dependent protein kinase II (CaM Kinase II) inhibitor, KN-93 potently inhibits gastric acid secretion from parietal cells. As previously reported (1), treatment of parietal cells with a selective inhibitor of CaM kinase II, KN-62 resulted in the inhibition of cholinergic-stimulated rabbit parietal cell secretion, whereas it failed to inhibit the histamine and forskolin response. In contrast effects of carbachol, histamine and forskolin were significantly inhibited by KN-93 with an IC50 of 0.15, 0.3 and 1 microM, respectively; these effects occurred without any changes in intracellular cyclic AMP and Ca2+ levels. In the present study we investigated the mechanism by which KN-93 acts upon the acid-secreting machinery of gastric parietal cells. Neither redistribution of the proton pump activity nor the morphological transformation were affected by KN-93. The drug only weakly inhibited the H+, K(+)-ATPase activity but strongly dissipated the proton gradient formed in the gastric membrane vesicles and reduced the volume of luminal space. Thus KN-93 acts at pH gradient formation whereas KN-62 acts only at CaM Kinase II.  相似文献   
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