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31.
An outbreak of gastroenteritis due to Salmonella Enteritidis phage type 4 occurred in people who attended a traditional hunting festivity in a small village in western Austria 6 through 11 November 2005. Of approximately 250 attendees, 227 had consumed dishes offered at the festival, and of these consumers 35 persons fulfilled the outbreak case definition (attack rate of 15.4%). Sp?tzle (traditional pastalike side dish) was most likely the contaminated part of the incriminated main course (relative risk of 18.9, 95% confidence interval of 4.6 to 76.7; P < 0.001). Thirteen eggs that remained from the preparation of the sp?tzle were negative for Salmonella when tested individually without shell disinfection, as were 1200 eggs collected at the egg production plant and examined with shell disinfection. The back-traced egg production farm had been initially certified as Salmonella free by a voluntary quality control program. However, an intensified environmental investigation of the incriminated egg production farm performed in the first quarter of 2006 and based on an appropriate method of sampling revealed Salmonella Enteritidis phage type 4 in 4 of 13 flocks. Although a combination of epidemiological and microbiological investigations allowed elucidation of the mode of spread, no restrictions were placed on the incriminated flocks of laying hens. These flocks were kept in production until they were stalled out due to age in August 2006. In June 2006, a cluster of 23 cases of Salmonella Enteritidis phage type 6 infection was again associated with this egg production farm. Evidence provided by epidemiological analyses is often disregarded by decision makers. However, negative results from microbiological testing of food involved in an outbreak are often weighted as strong evidence against a causal association between that food and the outbreak.  相似文献   
32.
Most printed material is produced by printing halftone dot patterns. One of the key issues that determine the attainable print quality is the structure of the paper surface, but the relation is non-deterministic in nature. We examine the halftone print quality and study the statistical dependence between the defects in printed dots and the topography measurement of the unprinted paper. The work concerns SC paper samples printed by an IGT gravure test printer. We have small-scale 2D measurements of the unprinted paper surface topography and the reflectance of the print result. The measurements before and after printing are aligned with subpixel resolution, and individual printed dots are detected. First, the quality of the printed dots is studied using Self Organizing Map and clustering and the properties of the corresponding areas in the unprinted topography are examined. The printed dots are divided into high and low print quality. Features from the unprinted paper surface topography are then used to classify the corresponding paper areas using Support Vector Machine classification. The results show that the topography of the paper can explain some of the print defects. However, there are many other factors that affect the print quality, and the topography alone is not adequate to predict the print quality.  相似文献   
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Thixoforming requires semi-solid slurries, which contain a high volume fraction of non-dendritic solid phase with special grain morphology. Volume fraction, geometry and connectivity of the solid -phase has to be kept within narrow limits. The paper illustrates the development of a new aluminium based wrought alloy AIMgSi1 alloy, adapted with barium, characterised by a microstructure which exhibits a low sensitivity towards fluctuations in process parameters resulting in improved mechanical properties of the alloy. The rheological behaviour of the new alloy by means of backward extrusion experiments is described, and an overview of the static and dynamic strength properties is given that can be achieved when the alloy is processed by means of the New Rheocasting process.  相似文献   
36.
A result-oriented approach to project management is described on the assumption that national requirements and the administration of the company are the most significant components of the project environment. A method is described of identifying certain key results and their corresponding objectives from the goals given by the environment, and their distribution between organization units and responsible persons. This approach is very useful, particularly in modern society where the expectations of the environment are becoming increasingly stringent.  相似文献   
37.
Detailed numerical simulations of fires in road tunnels were carried out using the CFD code JASMINE. Fire tests performed in the Ofenegg tunnel have also been validated. A parametric study of fires in an arbitrary 300-m-long tunnel was made, in which the influence of fire size, tunnel width, ventilation and ground slope was investigated. The movement of hazardous temperature and smoke regions as a function of time was calculated to vestigate escape possibilities from the tunnel in case of fire.  相似文献   
38.
Bioactive glasses (BAGs) have been studied for decades for clinical use, and they have found many dental and orthopedic applications. BAGs have also been shown to have an antibacterial effect e.g., on some oral microorganisms. In this extensive work we show that six powdered BAGs and two sol-gel derived materials have a clear antibacterial effect on 29 clinically important bacterial species. We also incorporated a rapid and accurate flow cytometric (FCM) method to calculate and standardize the numbers of viable bacteria inoculated in the suspensions used in the tests for antibacterial activity. In all materials tested growth inhibition could be demonstrated, although the concentration and time needed for the effect varied depending on the BAG. The most effective glass was S53P4, which had a clear growth-inhibitory effect on all pathogens tested. The sol-gel derived materials CaPSiO and CaPSiO II also showed a strong antibacterial effect. In summary, BAGs were found to clearly inhibit the growth of a wide selection of bacterial species causing e.g., infections on the surfaces of prostheses in the body after implantation.  相似文献   
39.
Allergic reaction following fish consumption can trigger life-threatening reactions in predisposed individuals. Parvalbumins from different species have been identified as the major fish allergens. There are two distinct phylogenetic lineages of parvalbumins, alpha and beta. Most allergic reactions are caused by beta-parvalbumins. We cloned and expressed cDNAs encoding cod (Gadus morhua) and carp (Cyprinus carpio) beta-parvalbumins and purified natural cod beta-parvalbumin. CD spectra of the purified proteins showed that their overall secondary structure contents were very similar. No differences in thermal stability were monitored in the calcium-bound or calcium-depleted form of natural cod parvalbumin. IgE reactivity was assessed using 26 sera of fish allergic patients from Spain, The Netherlands, and Greece in immunoblot and ELISA experiments. Twenty-five of the 26 patients with IgE reactivity to native and recombinant cod parvalbumin also reacted to the recombinant carp parvalbumin. IgE inhibition assays were performed using cod and carp extracts and purified recombinant parvalbumin of cod and carp. High crossreactivity among cod and carp parvalbumins was observed in immunoblots as well as in fluid phase assays. Natural and recombinant parvalbumins gave comparable results when performing various in vitro diagnostic assays.  相似文献   
40.
Inflammation and hypoxia impair alveolar barrier tightness, inhibit Na- and fluid reabsorption, and cause edema. We tested whether stimulated alveolar macrophages affect alveolar Na-transport and whether hypoxia aggravates the effects of inflammation, and tested for involved signaling pathways. Primary rat alveolar type II cells (rA2) were co-cultured with rat alveolar macrophages (NR8383) or treated with NR8383-conditioned media after stimulation with lipopolysaccharide (LPS; 1 µg/mL) and exposed to normoxia and hypoxia (1.5% O2). LPS caused a fast, transient increase in TNFα and IL-6 mRNA in macrophages and a sustained increase in inducible nitric oxide synthase (NOS2) mRNA in macrophages and in rA2 cells resulting in elevated nitrite levels and secretion of TNF-α and IL-6 into culture media. In normoxia, 24 h of LPS treated NR8383 decreased the transepithelial electrical resistance (TEER) of co-cultures, of amiloride-sensitive short circuit current (ISCΔamil); whereas Na/K-ATPase activity was not affected. Inhibition was also seen with conditioned media from LPS-stimulated NR8383 on rA2, but was less pronounced after dialysis to remove small molecules and nitrite. The effect of LPS-stimulated macrophages on TEER and Na-transport was fully prevented by the iNOS-inhibitor L-NMMA applied to co-cultures and to rA2 mono-cultures. Hypoxia in combination with LPS-stimulated NR8383 totally abolished TEER and ISCΔamil. These results indicate that the LPS-stimulation of alveolar macrophages impairs alveolar epithelial Na-transport by NO-dependent mechanisms, where part of the NO is produced by rA2 induced by signals from LPS stimulated alveolar macrophages.  相似文献   
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