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101.
A number of two-way radios, similar to those which have been employed to initiate Improvised Explosive Devices (IEDs), were acquired from a commercial supplier and grouped into four pairs. Samples of plastic material were collected from five distinct regions of each radio and analysed by Infrared and Raman spectroscopy to identify the nature of the material. One radio of each pair was then subjected to detonation with a commercially available plastic explosive. The combination of radio and explosive was considered to be representative of the components of an IED. Following detonation, fragments were recovered and, where possible, identified as specific sampling points of the radio.A combination of δ2H and δ13C stable isotopic analysis of material from each of the five sampling points was found to provide a pattern which was characteristic of a given radio and provided a means to associate pairs of radios. When few fragments were recovered, no positive association could be made between the fragments and the paired, undamaged radio. This was attributed, in part, to manufacturing variation in the radios. However, when three or more post-blast fragments were recovered it was possible to associate these with the paired, undamaged radio with a high degree of certainty.  相似文献   
102.
Forensic DNA typing is currently conducted in approximately 8–10 h. The process includes DNA extraction, quantitation, multiplex PCR amplification, and fragment length detection. Today's commercial multiplex short tandem repeat (STR) typing kits are not optimized for rapid PCR thermal cycling. Current protocols require approximately 3 h for amplifying a multiplex containing 15 STR loci plus amelogenin. With the continuing development of miniaturization technologies such as microfluidic and micro-capillary devices, there is a desire to reduce the overall time required to type DNA samples. Such miniature devices could be used for initial screening at a crime scene, at a border, and at airports. There is also the benefit of reducing the required PCR amplification time for labs typing single-source reference samples. Surveys of fast processing polymerases working in combination with rapid cycling protocols have resulted in the development of a ‘rapid’ PCR amplification protocol. Results are obtained in less than 36 min run on a standard peltier-based thermal cycler employing a heating rate of 4 °C/s. Capillary electrophoresis characterization of the PCR products indicates good peak balance between loci, strong signal intensity and minor adenylation artifacts. Genotyping results are concordant with standard amplification conditions utilizing a standard 3 h (non-rapid) thermal cycling procedure. The rapid assay conditions are robust enough to routinely amplify 0.5 ng of template DNA (with 28 cycles).  相似文献   
103.
Abstract: A short tandem repeat multiplex assay has been successfully developed with 25 autosomal loci plus the sex‐typing locus amelogenin for a total of 26 amplified products in a single reaction. Primers for the loci were designed so that all of the amplicons present were distributed from 65 base pairs (bp) to less than 400 bp within a five‐dye chemistry design with the fifth dye reserved for the sizing standard. A multiplex design strategy was developed to overcome challenges encountered in creating this assay. The limits of the multiplex were tested, resulting in the successful amplification of a wide range of genomic DNA sample concentrations from 2 ng to as low as 100 pg with 30 cycles of PCR. The 26plex has the potential to benefit the forensic community for reference sample testing and complex relationship evaluation.  相似文献   
104.
Public procurement is a large sector of the economy with most procurement going to the defense sector. Procurement by the defense sector includes purchases made through contracts to private businesses that manufacture durable goods. Manufacturing of these goods results in pollution production with toxic wastes being among the most dangerous pollutants for public health. Despite green purchasing policy goals, most transactions in the United States through defense contracts result in disproportionately high-toxic pollution releases by manufacturers. We find that persistent exemptions granted defense agencies from following green purchasing policy result in a landscape where contractor environmental performance is unchanging with defense contractors persistently polluting in high amounts. Further, we find that defense contractors are linked to most toxic releases from procurement meaning that exemptions may be hindering potential advancements from green purchasing policy. Results can inform the design of new guidance about procurement and expand understanding of environmental inequality.  相似文献   
105.
Lisa Hill 《政治学》2001,21(2):101-113
This article responds to recent cases of parliamentary speech which reflect the ascendancy of a totalising 'mainstream' approach to public discourse and a political leadership that may, at times, be overly attentive to the majority-rule dimension of democracy. These developments spark a more general discussion of the phenomenology of privileged parliamentary speech, the role of speech freedoms in liberal democratic orders and the duties of parliamentary representatives within them. I make two general conclusions. First, the ways in which we normally argue and think about free speech will not generally apply to the speech of parliamentarians because their speech rights cannot be universalised. Secondly, even if parliamentary speech could be treated as standard speech there would be no legitimate defence (from a liberal democratic point of view) for a strictly populist approach to its use since this could undermine the deliberative function of parliament and lead to the violation of other important liberal democratic principles.  相似文献   
106.
This article examines the implications of high levels of informal (or invalid) voting in Australian national elections using a social exclusion framework. The rate of the informal vote is an indicator of social and political exclusion with particular groups of Australians experiencing inordinate electoral disadvantage. Poorer voters, voters from non‐English speaking backgrounds and those with low education levels are especially disadvantaged by factors peculiar to the Australian voting experience. We begin by exploring the character and pattern of informal voting and then canvass the technical and socio‐economic factors which explain it. We conclude by considering proposed options for reducing informality, some of which are: the abandonment of compulsory voting, major structural change to the voting system as well as ballot re‐design, electoral education and community information initiatives.  相似文献   
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Hiatus hernia is a common condition and while medical treatment is often sufficient, in some cases surgery may be necessary. Although there are a number of surgical treatments available, none has been totally successful. We report a case in which use of the Angelchik prosthesis proved fatal.  相似文献   
110.
This study investigated the relationship between 10 characteristics of childhood sexual abuse and dissociation in adulthood. A structured clinical interview, the Dissociative Experiences Scale, and the Dissociation Subscale of the Symptom Checklist 90 - Revised were administered to 118 women survivors seeking psychotherapy. Separate stepwise multiple regression analyses were conducted for each dissociation scale to determine which abuse characteristics were predictive of dissociation. In both analyses, the same four variables were significantly related to dissociation: age at onset, coercive sexual acts, objectifying sexual acts, and concurrent multiple perpetrators. Implications of findings for future research and clinical practice are explored.  相似文献   
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