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61.
Reports of foodborne disease incidents in Sweden from 1992 to 1997 are summarized. The results are based on reports from the municipal environmental and public health authorities to the National Food Administration and from medical authorities to the Swedish Institute for Infectious Diseases Control. A total of 555 incidents, of which 84% were outbreaks, were reported, involving 11,076 ill people. In 66% of the incidents, no disease agent was determined. Bacterial agents were implicated in 25% and viruses in 8% of the incidents. Calicivirus was the most reported agent both in terms of incidents and cases. Mixed dishes was the food category most often implicated in outbreaks, and smorgasbord and casserole or stews were the subcategories that caused the most cases. The place of consumption was unknown in 8% of the incidents. In about 60% of the incidents, the implicated food was consumed in commercial food establishments; in approximately 20% of incidents, it was consumed at home. The average annual incidence of reported foodborne disease in Sweden was estimated to be 21 cases per 100,000. The average annual incidence of reported foodborne salmonellosis and campylobacteriosis was estimated to be 2.0 and 0.6 cases per 100,000, respectively. The awareness and motivation to report foodborne diseases need to be improved, but additional sources of information are needed to counteract some of the limitations of reporting discussed in this work. 相似文献
62.
Framework for Value of Information Analysis in Rock Mass Characterization for Grouting Purposes 总被引:1,自引:0,他引:1
M. Zetterlund T. Norberg L. O. Ericsson L. Rosén 《Canadian Metallurgical Quarterly》2011,137(7):486-497
The observational method involves recurrent updating, and according to European standards, it is an optional method when geotechnical conditions are difficult to predict. A method for the application of value of information analysis in rock mass characterization for tunnels is demonstrated in a generic case of a feasibility study of a tunnel in hard rock. Two alternative grouting designs are analyzed to find the most suitable design for the geological conditions on site and whether information from investigations is of value in the decision-making process. The uncertainty in the grouting result is described by means of a beta distribution for each alternative design. The probabilities of different geological states are based on 200 stochastic simulations of the rock mass. It was found that value of information analysis contributes to good structure in geological surveys when the geology is difficult to predict and when repeated updating is necessary. The prescribed method is a tool to design well-motivated investigation programs where geotechnical value is weighed up against execution costs. 相似文献
63.
A LixMnPO4 (x = 1.0–0.15) composite cathode was investigated by Fourier-transform infrared spectroscopy at different states of charge. Significant spectral changes of the PO43− vibrations, which are correlated with the Jahn–Teller distortion of Mn3+ in MnPO4 and the 3rd ionization potential of Mn, were observed upon electrochemical delithiation of LiMnPO4. The presence of two sets of peaks observed in the series of delithiated LixMnPO4 spectra is consistent with a two-phase process for delithiation. These results provide insight into the structural changes that occur during lithium extraction and insertion in LiMnPO4. 相似文献
64.
Identifying the most suitable risk-reduction measures in drinking water systems requires a thorough analysis of possible alternatives. In addition to the effects on the risk level, also the economic aspects of the risk-reduction alternatives are commonly considered important. Drinking water supplies are complex systems and to avoid sub-optimisation of risk-reduction measures, the entire system from source to tap needs to be considered. There is a lack of methods for quantification of water supply risk reduction in an economic context for entire drinking water systems. The aim of this paper is to present a novel approach for risk assessment in combination with economic analysis to evaluate risk-reduction measures based on a source-to-tap approach. The approach combines a probabilistic and dynamic fault tree method with cost-effectiveness analysis (CEA). The developed approach comprises the following main parts: (1) quantification of risk reduction of alternatives using a probabilistic fault tree model of the entire system; (2) combination of the modelling results with CEA; and (3) evaluation of the alternatives with respect to the risk reduction, the probability of not reaching water safety targets and the cost-effectiveness. The fault tree method and CEA enable comparison of risk-reduction measures in the same quantitative unit and consider costs and uncertainties. The approach provides a structured and thorough analysis of risk-reduction measures that facilitates transparency and long-term planning of drinking water systems in order to avoid sub-optimisation of available resources for risk reduction. 相似文献
65.
66.
J S?derstr?m C Arnerl?v SO Emdin B Lundgren G Roos L Bjersing C Norberg KA Angquist 《Canadian Metallurgical Quarterly》1997,193(7):485-490
One hundred and fifty-eight histologically verified mammary carcinomas with known mammographic doubling time (DT) were studied with special emphasis on a morphologic classification proposed by Linell et al. [8, 12, 14, 15]. The hypothesis that Linell classification of ductal carcinomas into comedo, tubuloductal and tubular carcinomas is easy to perform with small inter-observer variations, was not fully confirmed. The Linell classification was found to correlate well with conventional WHO malignancy grading, S-phase fraction and DNA-ploidy. The Linell classification also correlated to surgical stage, lymph node status and DT, but not at all to tumour size. Using distant disease-free survival as an endpoint, the Linell classification gave prognostic information comparable to conventional histologic grading, seeming to be a simple, cheap and reliable method well worth trying on a larger scale. 相似文献
67.
The integration of more and more functionality into smaller and smaller form factor electronic products, drives the need for denser chip to substrate interconnect systems. As the number of I/O pins increases, the use of area array chips or packages becomes inevitable. Metal patterned elastomer chip sockets have now been improved to work with contact densities as high as 80 000 contacts/cm/sup 2/ corresponding to a pitch of 36 /spl mu/m. Sockets with 10 000 contacts and a 72-/spl mu/m pitch have survived more than 400 cycles in air-to-air thermal cycling chambers as well as freezing shocks caused by dipping into liquid nitrogen. Although the daisy chain test circuits breaks for temperatures lower than -50/spl deg/C and higher than 90/spl deg/C, they always return to the initial resistance values when entering the normal temperature range. The combination of a gold-to-gold contact interface and the elastic features of the contact bumps makes this socket an ideal compliance layer between bare chips and different types of carrier substrates, reducing the problems caused by thermomechanical mismatch between the substrate and the chip. Bad dies can easily be replaced, since the chip is not soldered or glued to the socket. The size and the possibility to control the geometry of the contacts provides means to maintain a good high-frequency characteristic impedance matching all the way to the chip pad. 相似文献
68.
As part of the energy and indoor climate survey recently carried out in Sweden (the ELIB study) a simple, inexpensive but reliable passive sampler for estimating monthly averages of relative humidity has been developed. The diffusion sampler consists of a 5 ml plastic tube prepared with lithium chloride monohydrate (LiCl. H2O) as trapping medium. After necessary calibration of this particular design of sampler the relative humidity can be calculated from the weight change of the sampler, the time of sampling and the average temperature during this period. The estimated accuracy of the method is better than k 2% RH up to65% RH. 相似文献
69.
70.
BACKGROUND: The current study investigated the fundamental nature of the cognitive processing deficit that has been demonstrated to be associated with dieting to lose weight. Previous work has characterized this deficit as being primarily one of a reduction in working-memory capacity. The present study investigated the particular components of the working-memory system affected during dieting. METHOD: A sample of female subjects was classified as either low/medium restrained eaters (N = 34), highly restrained eaters (N = 18) or current dieters (N = 19), based on their responses to a modified version of the Dutch Eating Behaviour Questionnaire (DEBQ). Each subject completed tasks that assessed the Visuo-Spatial Sketchpad (mental rotation), Phonological Loop (effect of phonological similarity on recall) and the Central Executive (Tower of London Task) components of working memory. RESULTS: Those subjects who reported themselves to be currently dieting displayed poorer recall on the Phonological Loop task and slower planning times on the Tower of London Task. Performance on both these tasks correlated significantly with a self-report measure of body shape concern. CONCLUSIONS: These results support the hypothesis that the mediating variable in this deficit is that of preoccupying cognitions concerning food and body shape. 相似文献