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81.
A total of 800 meat and poultry products were purchased from the retail marketplace in Edmonton, Alberta, Canada. The products consisted of raw ground beef, chicken legs, pork chops, and ready-to-eat fermented sausage, roast beef, processed turkey breast, chicken wieners, and beef wieners. The samples were analyzed to determine the prevalence of Shiga toxin-producing Escherichia coli, Salmonella, Campylobacter spp., and Listeria monocytogenes. Shiga toxin-producing E. coli 022: H8 was found in one raw ground beef sample. Salmonella and Campylobacter were found in 30 and 62% of raw chicken legs, respectively. L. monocytogenes was found in 52% of raw ground beef, 34% of raw chicken legs, 24% of raw pork chops, 4% of fermented sausages, 3% of processed turkey breast, 5% of beef wieners, and 3% of chicken wieners. The occurrence of pathogens in this study is similar to that in retail products in many other international locales.  相似文献   
82.
The pace of war is increasing since militaries are adopting the ideas of NCW (network centric warfare). Therefore, the process of war has to be modeled into the BP (business process) in order to benefit from available resources in real-time. There is an increasing need to automate command and control tools utilized in military operations because of the versatility and increase d tempo of operations. Operations can be commanded and orchestrated with the assistance of SOA (service oriented architecture). SOA is currently seen as a technology that can satisfy these needs of NCO (network centric operations). The BPs are chains of logic that request SOA services. This paper argues that in the case of a military setting, in order to achieve maximum impact with minimal effort (cf. downsizing), military operations need to be modeled as BPs (e.g., a dismounted company attack). This asks for using a RM (resource manager), a scheduler and a BSS (battle secure scheduler) in allocating the requested services (e.g., processing a fire support order). In the future, a single FFW (future force warrior), an essential performer in military operations, can benefit from the BPs approach via enhanced performance, improved SA (situational awareness) and with decreased instances of fratricide. This introduced model examines war as a business process with the assistance of SOA and discusses how a business process--like orchestration of systems and services can improve the overall performance in given military settings.  相似文献   
83.
International Journal of Computer-Supported Collaborative Learning - The coordination of cognitive and non-cognitive interactive processes contributes to successful collaboration in groups, but it...  相似文献   
84.
The International Flow of Television Programs   总被引:2,自引:1,他引:1  
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85.
Both thermal and catalytic decomposition of diborane resulting in borane as the main product were investigated under the pressure and temperature ranges of 2–15 bar and 100–300 °C, respectively over Al2O3 and Pt/Al2O3 in a fixed bed reactor. Catalytic decomposition rate was essentially higher than the thermal decomposition, however the catalyst deactivation was substantial.  相似文献   
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87.
MT-PVLT-10 transgenic mice express the large T-antigen of polyomavirus under the control of the mouse metallothionein-1 promoter. The males of this transgenic line developed testicular tumor and seminal vesicle engorgement at advanced ages. A novel partial cDNA was identified which hybridized to a 2.6 kilobase mRNA. The expression of this mRNA increased approximately two- to fifteen-fold in immortalized cell lines derived from testicular tumors as compared to similar cell lines derived from pre-adenomatous testes. The in vivo pattern of expression for this cDNA as well as its expression in various primary cultures and established cell lines derived from testis of MT-PVLT-10 mice is presented. Overlapping cDNA clones from liver, testes, and brain cDNA libraries containing the entire coding region for this novel cDNA have been isolated and sequenced. The coding region of this gene comprises 1179 nucleotides and predicts a polypeptide of 393 amino acids (calculated molecular mass 44,318). Motif analysis of the amino acid sequence has revealed that it contains several hydrophobic alpha-helices characteristic of transmembrane proteins.  相似文献   
88.
The kinetics of the chlorination of acetic acid (HAc) to monochloroacetic acid (MCA) and the physical solubility of chlorine in HAc and its mixtures with MCA were investigated in a laboratory scale semibatch reactor. The temperature dependence of the Henry's constant was determined from solubility data obtained at temperatures between 70°C and 110°C. The kinetic experiments were performed at 75–100°C with 3–13 mol % acetyl chloride (AcCl) and 0–5 weight % H2SO4 added as catalysts. Gas chromatography was used to determine the concentrations of HAc, MCA, dichloroacetic acid and AcCl during the experiments. The results indicate that the reaction rate is independent of the concentrations of HAc and Cl2 whereas the reaction is significantly enhanced by MCA and H2SO4. The effects are explained by a reaction mechanism involving the acid catalyzed enolization of AcCl as the rate-determining step. A rate equation based on this mechanism was derived. Kinetic constants included in the equation were determined by regression analysis.  相似文献   
89.
90.
Only a subset of the boundary points—the segment borders—have to be taken into account in searching for the optimal multisplit of a numerical value range with respect to the most commonly used attribute evaluation functions of classification learning algorithms. Segments and their borders can be found efficiently in a linear-time preprocessing step.In this paper we expand the applicability of segment borders by showing that inspecting them alone suffices in optimizing any convex evaluation function. For strictly convex evaluation functions inspecting all segment borders is also necessary. These results are derived directly from Jensen's inequality.We also study the evaluation function Training Set Error which is not strictly convex. With that function the data can be preprocessed into an even smaller number of cut point candidates, called alternations, when striving for optimal partition. Examining all alternations also seems necessary, since—analogously to strictly convex functions—the placement of neighboring cut points affects the optimality of an alternation. We test empirically the reduction of the number of cut point candidates that can be obtained for Training Set Error on real-world data.  相似文献   
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