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This paper focuses attention on emergency management associated with a terrorist attack in the transport of hazardous materials in urban areas. The case study is in an urban area, a potential target for terrorist attacks due to its high vulnerability. Since it is not possible to predict where and when an attack will occur, the risk associated with terrorism is complex. It is only possible to identify the critical points for potential actions where counter measure must be applied. In the case of incidents which evolve relatively slowly, mitigation actions can be applied. The use of dynamic geoevents permits the immediate location of the event on a georeferenced map and the possibility of having a dynamic evolution of the scenario and of the number of people involved. The dynamic scenario has been created using the output of a consequence simulation code and a GIS software. Some assumptions were necessary but, since the aim of the paper is to define the procedure for the construction of the dynamic geoevent, these can be considered acceptable. The method will be further implemented in future.  相似文献   
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The diagnosis of chromosomal mosaicism in the preimplantation and prenatal stage is fraught with uncertainty and multiple factors need to be considered in order to gauge the likely impact. The clinical effects of chromosomal mosaicism are directly linked to the type of the imbalance (size, gene content, and copy number), the timing of the initial event leading to mosaicism during embryogenesis/fetal development, the distribution of the abnormal cells throughout the various tissues within the body as well as the ratio of normal/abnormal cells within each of those tissues. Additional factors such as assay noise and culture artifacts also have an impact on the significance and management of mosaic cases. Genetic counseling is an important part of educating patients about the likelihood of having a liveborn with a chromosome abnormality and these risks differ according to the time of ascertainment and the tissue where the mosaic cells were initially discovered. Each situation needs to be assessed on a case-by-case basis and counseled accordingly. This review will discuss the clinical impact of finding mosaicism through: embryo biopsy, chorionic villus sampling, amniocentesis, and noninvasive prenatal testing using cell-free DNA.  相似文献   
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Most species of social insect are characterized by a reproductive division of labor among morphologically specialized individuals. In contrast, there exist many species where all individuals are morphologically identical and dominance relationships determine which individuals mate and/or reproduce. In newly founded multiple-foundress associations of the social wasp Polistes dominulus, foundresses establish dominance hierarchies where the top-ranked (alpha) female monopolizes egg laying. The possibility that chemical cues are used for recognition of egg-laying individuals has not been explored in this wasp. Using non-destructive techniques, we examined the relationship between ovarian activity and the proportions of cuticular hydrocarbons of three female types (dominant and subordinate foundresses and workers) in 11 colonies. Immediately after nest foundation, no differences were found between alpha and subordinate females. In contrast, at worker emergence, alpha females were statistically distinguishable from both subordinates and workers. We experimentally removed the alpha female in 5 of the original nests and reanalyzed hydrocarbon proportions of the new dominant individual. Replacement individuals were all found to acquire a cuticular signature characteristic of the alpha female. This suggests that cuticular hydrocarbons are used as cues of ovarian activity in P. dominulus, and we discuss our results in terms of a switch from behavioral dominance to chemical signaling in this wasp.  相似文献   
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