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21.
In summer 1991 an outbreak of a Salmonella enteritidis epidemic involving about 600 cases of gastroenteritis occurred at one of the leading pharmaceutical companies in southwestern Germany. The main source was a cold fruit soup, in addition Salmonella were isolated from meat strips and a curd cheese which were used for a salad dressing. A total of 2300 contaminated food portions were served resulting in an attack rate of about 25%. The possible origin could have been an asymptomatic Salmonella-positive member of the kitchen personnel who was the only one who was involved with the preparation of all the incriminated foods. A further spread of the epidemic and especially the possible contamination of pharmaceuticals was avoided by the timely and adequate reaction of the company's occupational medical service. This case exemplifies how classical crisis management, "increased initiative on one's own for prevention of infections in all areas of food processing" (Steuer) and finally the cooperation of the company with different institutions of the public health authorities contribute to the control of such a catastrophic scenario. 相似文献
22.
The use of information technology to enhance teaching and learning processes has been practiced for a number of years now.
However, the rapid growth in the use of the Internet has led to a new dimension in interactive and collaborative learning
anytime and anyplace dynamically. With the explosion of “virtual education initiatives”, the question of the feasibility and
success criteria for such projects quickly arises. To address the question in an organized way, we propose a project assessment
based on critical success factors. Hence, in this article, we draw on a widely recognized critical success factor framework.
We (slightly) adjust the framework to fit the special characteristics of virtual education initiatives, and apply to one case
study, namely the virtual education initiative at the Faculty of Business at the City University of Hong Kong. The results
suggest that the past success of the case is due to the adherence to the large majority of critical success factors. However,
it also outlines some areas of concern. The paper concludes with a discussion on the strength and limitations of virtual learning
environment as well as future directions.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
23.
分辨率增强技术(RET)设计流程中聚集了各式各样的点工具和方法。当前对深亚波长可制造性(DFM)设计的要求迫使设计与制造行业必须建立十分密切的合作关系。同时也促使EDA行业提供一种平台,以促进这些行业间的密切交流。合理利用这一平台将会对产能和品质产生直接的影响。 相似文献
24.
Floris Bex Henry Prakken Chris Reed Douglas Walton 《Artificial Intelligence and Law》2003,11(2-3):125-165
This paper studies the modelling of legal reasoning about evidence within general theories of defeasible reasoning and argumentation. In particular, Wigmore's method for charting evidence and its use by modern legal evidence scholars is studied in order to give a formal underpinning in terms of logics for defeasible argumentation. Two notions turn out to be crucial, viz. argumentation schemes and empirical generalisations. 相似文献
25.
K. W. Brodlie D. A. Duce J. R. Gallop J. P. R. B. Walton J. D. Wood 《Computer Graphics Forum》2004,23(2):223-251
Visualization is a powerful tool for analyzing data and presenting results in science, engineering and medicine. This paper reviews ways in which it can be used in distributed and/or collaborative environments. Distributed visualization addresses a number of resource allocation problems, including the location of processing close to data for the minimization of data traffic. The advent of the Grid Computing paradigm and the link to Web Services provides fresh challenges and opportunities for distributed visualization—including the close coupling of simulations and visualizations in a steering environment. Recent developments in collaboration have seen the growth of specialized facilities (such as Access Grid) which have supplemented traditional desktop video conferencing using the Internet and multicast communications. Collaboration allows multiple users—possibly at remote sites—to take part in the visualization process at levels which range from the viewing of images to the shared control of the visualization methods. In this review, we present a model framework for distributed and collaborative visualization and assess a selection of visualization systems and frameworks for their use in a distributed or collaborative environment. We also discuss some examples of enabling technology and review recent work from research projects in this field. 相似文献
26.
Ju Eun Lee David Walton Colleen P. OConnor Michael Wammes Jeremy P. Burton Elizabeth A. Osuch 《International journal of molecular sciences》2022,23(12)
Emerging adulthood (ages 18–25) is a critical period for neurobiological development and the maturation of the hypothalamic–pituitary–adrenal axis. Recent findings also suggest that a natural perturbation of the gut microbiota (GM), combined with other factors, may create a unique vulnerability during this period of life. The GM of emerging adults is thought to be simpler, less diverse, and more unstable than either younger or older people. We postulate that this plasticity in the GM suggests a role in the rising mental health issues seen in westernized societies today via the gut–brain–microbiota axis. Studies have paid particular attention to the diversity of the microbiota, the specific function and abundance of bacteria, and the production of metabolites. In this narrative review, we focus specifically on diet, physical activity/exercise, substance use, and sleep in the context of the emerging adult. We propose that this is a crucial period for establishing a stable and more resilient microbiome for optimal health into adulthood. Recommendations will be made about future research into possible behavioral adjustments that may be beneficial to endorse during this critical period to reduce the probability of a “dysbiotic” GM and the emergence and severity of mental health concerns. 相似文献
27.
This article analyzes the possibilities of applying Continuous Improvement principles to the management and maintenance of academic library websites. Current practice is mapped onto Continuous Improvement principles, with evidence distilled from a United Kingdom national survey of academic library web practitioners. The survey data informs a website organizational framework and operational model. The framework describes the setting within which library websites are managed, while the model focuses on library specific aspects to the management and development of their site. 相似文献
28.
Doug Williams Marian F. Ursu Joshan Meenowa Pablo Cesar Ian Kegel Karl Bergström 《Telematics and Informatics》2011
This paper discusses results from research related to the use of television as a device that supports social interaction between close-knit groups in settings that include more than two locations, each location being potentially equipped with more than one camera. The paper introduces the notion of a framing experience, as a specific scenario or situation within which social communication takes place. It reports on the evaluation of some of the key attributes of social communication through semi-structured interviews, with 16 families across four European countries. The inferences drawn from this study are reduced to four system capabilities including the ability to support: excitement, engagement and entertainment; high quality, reliable audiovisual communications; flexibility and adaptability sufficient to support the unpredictable and reactive nature of human interaction and discourse. These system requirements are, in turn, reduced to a number of technology challenges which if solved will help enable effective social communications between groups, mediated by the television. These technology challenges include: high quality reliable audio visual communication; interaction orchestration, multimedia interpretation and multimedia composition. Finally the paper reflects on the impact the use of framing experiences, such as those described here, could have on strategy and policy for service providers and regulators. 相似文献
29.
A physical strategy for the preparation of isotactic polypropylene spheres with microsphere and bead–string spherulite morphologies 下载免费PDF全文
This study mainly focuses on the formation of isotactic polypropylene (iPP) blend morphologies with microspheres and distinct bead–string spherulites. iPP microspheres have been prepared by a simple and convenient strategy through either an isothermal or a nonisothermal crystallization process based on the macrophase‐separated structure in molten state of iPP/olefin block copolymer (OBC) blend. The dimension of the iPP spheres can be adjusted easily from about 1 µm to >10 µm by controlling the compatibility and annealing conditions. It was found that any of the following three parameters, the molecular structure of OBC (particularly the octene content), molecular weight of iPP, and annealing condition can be rescaled with others in controlling the dimension of the iPP microspheres. The mechanism of the formation of iPP microspheres was studied in detail. Surprisingly, the typical spinodal decomposition morphology with interconnected or thin sheet structure is the precursor of these microspheres. During the subsequent annealing process, it breaks up and further coarsens into spherical structure. In addition, distinct spherulites with a bead–string substructure have been obtained during the isothermal crystallization. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40863. 相似文献
30.
David W. Niles Xiaonan Li David Albin Doug Rose Timothy Gessert Peter Sheldon 《Progress in Photovoltaics: Research and Applications》1996,4(3):225-229
A commonly used process for forming low-resistance contacts to thin-film p-type CdTe involves the formation of a Te layer by etching the CdTe film in a concentrated mixture of nitric and phosphoric acids. The authors compare evaporated Te back contacts with ‘control’ back contacts formed by the usual etching process, and demonstrate that evaporating Te onto a CdTe thin film is a viable process for forming a low-resistance contact. The best efficiency achieved for a CdTe solar cell made with an evaporated Te back contact is 12.1%, whereas the efficiency of the device made with the control back contact was 11.9%. The evaporation process offers numerous advantages over acid etching, most notably vacuum compatibility amenable to large-scale production of CdTe solar cell modules. 相似文献