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171.
The nature of blood aerosols produced in physiological studies of an upright subject expiring small volumes through straws, spitting and mouthing sounds, and a semi-prone subject spitting through a bloody mouth or snorting through a single nasal orifice and by a simplified physical model of the respiratory system were investigated. Each manoeuvre produced many hundreds of droplets of a range of size, the vast majority being less than 1mm diameter. Droplets under 1mm dia. travelled over 1m - much further than could be expected if their flight was ballistic, like that of impact spatter. Respired blood aerosol properties are explained in terms of established mechanics of airflow shear induced aerosol production and the fluid mechanics of exhaled air movement.  相似文献   
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Abstract: This paper reports the results of a commission to develop a field deployable rapid short tandem repeat (STR)‐based DNA profiling system to enable discrimination between tissues derived from a small number of individuals. Speed was achieved by truncation of sample preparation and field deployability by use of an Agilent 2100 BioanalyserTM. Human blood and tissues were stabbed with heated stainless steel wire and the resulting sample dehydrated with isopropanol prior to direct addition to a PCR. Choice of a polymerase tolerant of tissue residues and cycles of amplification appropriate for the amount of template expected yielded useful profiles with a custom‐designed quintuplex primer set suitable for use with the BioanalyserTM. Samples stored on wires remained amplifiable for months, allowing their transportation unrefrigerated from remote locations to a laboratory for analysis using AmpFlSTR® Profiler Plus® without further processing. The field system meets the requirements for discrimination of samples from small sets and retains access to full STR profiling when required.  相似文献   
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To assess if Benford's law, a mathematical law used for quality assurance in accounting, can be applied as a quality assurance measure for the manner of death determination. We examined a regional forensic pathology service's monthly manner of death counts (N = 2352) from 2011 to 2013, and provincial monthly and weekly death counts from 2009 to 2013 (N = 81,831). We tested whether each dataset's leading digit followed Benford's law via the chi‐square test. For each database, we assessed whether number 1 was the most common leading digit. The manner of death counts first digit followed Benford's law in all the three datasets. Two of the three datasets had 1 as the most frequent leading digit. The manner of death data in this study showed qualities consistent with Benford's law. The law has potential as a quality assurance metric in the manner of death determination for both small and large databases.  相似文献   
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The article focuses on the microeconomic foundations and effects of the fragile tax base in Sub-Saharan Africa, which have been insufficiently taken into account by the international financial institutions. Two vicious circles are analysed. The first addresses the political economy of states: their inability to redistribute revenues reinforces a lack of credibility, leading to a reluctance by the majority of the population to pay taxes. Instead, there is ongoing reliance on private interpersonal transfers. This is compounded by the way markets interlock, creating negative effects in terms of efficiency. This vicious circle is related to a second one, which stems from the nature of the social contracts that link citizens to the state, and which are rarely of the individualistic-voluntary type characteristic of developed states. States, therefore, are often not part of the reciprocity chain, which explains the failure of some reforms in Africa.  相似文献   
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The advent of the human genome sequence has focused research on understanding underlying genetic links to complex diseases such as cancer, asthma and heart disease. In the past few years, individual countries, such as Iceland, Estonia, Singapore and the United Kingdom, have created national databases of their citizens' DNA for comparative research. Most recently, an international consortium including Nigeria, Japan, China and the United States launched a $100 million project called the International HapMap to map the human genome according to haplotypes, blocks of DNA that contain genetic variation. Such population genetic databases present challenging ethical, social and legal issues, yet regulation of genetic information has developed sporadically, from region to region, without a consistent international standard. Without a clear understanding of the consequences of genetic research in terms of individual and community-wide discrimination and stigmatization, genetic databases raise concerns about the protection of genetic information. This Note provides a survey of the evolving landscape of population genetic databases as a legislative and public policy tool for national and international regulators. It compares different approaches to regulating the collection and use of population genetic databases in order to understand what areas of consensus are formulating a foundation for an international standard. As the first population genetics project that will span multiple countries for the collection of DNA, the International HapMap has the potential to become an influential standard for the protection of population genetic information. This Note highlights issues among the national databases and the HapMap project that raise ethical, social and legal concerns for the future and recommends further protections for both individual donors and community interests.  相似文献   
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Bjerklie D  Park A  Song S 《Time》2004,164(23):82-3, 85-6, 89-90 passim
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