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31.
Stutter products generated during DNA amplification by the polymerase chain reaction (PCR) may complicate mixture interpretation. The PCR amplification of the DYS392 locus typically results in three distinct detectable PCR products: the true allele product (N), a stutter product three bases smaller (N-3), and a reproducible low-level product, three bases larger (N+3). Sequence analysis of the N+3 product demonstrated that its sequence is one TAT repeat longer than the true allele product. Our experiments demonstrated that the quantity of both N-3 and N+3 stutter increased as the allele number increased. The percent stutter also increased as the magnesium concentration was increased in the reaction, as well as when the amount of input DNA was decreased. As both stutter products behave in a similar and reproducible fashion, the same rules that apply to the interpretation of N-3 stutter products in short tandem repeat analysis, can be applied to N+3 stutters. The characterization of the DYS392 N+3 product is the first detailed published study of a stutter product larger than the true allele. 相似文献
32.
Given growing concerns about the loss of farmland in the US, governmental and nonprofit groups are seeking innovative, cost-effective
methods to preserve lands that will elicit additional landowner participation. This article describes four innovative farmland
preservation techniques and derives implications for the policy process through interviews of key stakeholders: program administrators,
lawmakers, and landowners. Experts on farmland preservation were also interviewed to ensure stakeholder perceptions substantively
inform the policy process. Four techniques were selected for assessment from approximately 30 novel techniques. Reactions
to these policy options reflect stakeholder perceptions of a baseline condition; the perceptions help evaluate which options
are likely to survive the policy process and what attributes will lead to their acceptability because few of these techniques
have yet become policy. Although the stakeholders may have more limited experience with the policy process, land preservation
experts validated many of the results and the possibility of success in the “rough and tumble” of the policy process. Of the
four investigated techniques rights of first refusal was the most favored, although respondents thought effective implementation
would require careful targeting and a dedicated funding source. Experts agreed this technique was most likely to survive in
the political arena. Agricultural conservation pension was also viewed favorably, though it was considered administratively
difficult to implement. Several experts thought that, though inchoate, the pension plan could potentially be more cost effective
than rights of first refusal. Land preservation tontines were perceived to be an interesting concept, but confusing, difficult
to implement, and ill-defined. Term conservation easements were viewed unfavorably because they did not preserve land permanently.
相似文献
Lori LynchEmail: |
33.
Matt Andrews 《公共行政管理与发展》2012,32(2):137-153
Developing countries are pressured to adopt administrative solutions that the international community considers best practice. Some claim that these practices do not fit such contexts. How could one assess the fit or relevance of a best practice? This article suggests a basic answer: Look at the degree of difference between the proposed adoption context and the context in which such practice emerged as ‘best’. This answer emerges from a discussion on the basis of the new institutional ideas about change and diffusion. An empirical analysis of public financial management reform in African countries suggests support for this answer: Good practices are most evident in countries least different to the developed nations where practices originated and least evident in countries most different to these developed nations. The article contributes to a literature on best practice and yields fundamental messages for development, including the point that best practices are limited as administrative solutions in many developing countries. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
34.
The U.S. electricity market, like electricity markets in most countries, is heavily dependent on fossil-fuel generation from centralized power applications. This paper reviews the factors that led to the sector??s reliance on fossil fuels and presents a future vision of the U.S. electricity sector based on a varied spectrum of sustainable energy resources ranging in scale from large, centralized facilities to small, localized energy systems. This spectrum includes low-emissions energy and energy efficiency, as well as macro-generation, micro-grids, distributed generation, micro-generation and end-user conservation. We discuss the evidence that each element of this spectrum is a viable and proven technology, the balanced integration of which could shape an electricity sector that adheres to sustainability principles. This paper concludes with a discussion of the institutional barriers that need to be addressed to successfully achieve a transition toward a more future sustainable electricity sector based on the variations in scale. 相似文献
35.
Can and should political liberals recognize and otherwise support legal marriage as a matter of basic justice? In this article,
we offer a general account of how political liberals should evaluate the issue of whether the legal recognition of marriage
is a matter of basic justice. And, we develop and examine some public reason arguments that, given the fundamental interests
of citizens, could justify various forms of legal marriage in some contexts. In particular, in certain conditions, the recognition
of some form of legal marriage may be the best way to protect the fundamental interests of women as citizens in freely chosen
associations. Or, it may be that, in certain conditions, to secure the social conditions necessary for gays, lesbians and
bisexuals to be free and equal citizens, some form of legal marriage can or should be recognized. 相似文献
36.
Phenazepam is a long-acting benzodiazepine that, unlike other benzodiazepines, is currently not scheduled as a narcotic in Finland, most other European countries or the USA. It is used as an anxiolytic, sedative-hypnotic and anti-epileptic, mainly in Russia. In Finland, as well as in some other countries, an increase in the unauthorized use of phenazepam has been observed in recent years. In the one year period between July 1, 2010 and June 30, 2011 the prevalence of phenazepam in Finland was assessed among drivers apprehended for driving under the influence of drugs (DUID), in medico-legal autopsy cases and in police confiscations of illicit drugs. In DUID cases an LC-MS/MS method preceded by solid phase extraction was used for the determination of phenazepam. In the post-mortem investigations the sample preparation consisted of liquid-liquid extraction followed by derivatization and the determination was carried out by GC-MS. The police confiscations were analysed by GC-MS. There were 141 positive phenazepam cases among apprehended drivers, representing approximately 3.5% of all confirmed drug cases (n=4007) in this time period. The median (range) phenazepam blood concentration in DUID cases was 0.061 mg/L (0.004-3.600 mg/L). The median phenazepam concentration in cases with no concomitant stimulant use was significantly higher than the overall median concentration. Phenazepam was found in 17 medico-legal autopsy cases and the median (range) blood concentration was 0.048 mg/L (0.007-1.600 mg/L). Phenazepam was not considered by the medico-legal team to be the sole cause of death in any of the cases, the majority of them being accidental opiod overdoses. There were 26 seizures of phenazepam by the Police in the time period studied, some of the batches consisted of a mixture of phenazepam and stimulant designer drugs. The data show that phenazepam abuse is a widespread phenomenon in Finland. A typical user was a male multi-drug user in his 30s. The concentration range of phenazepam among apprehended drivers and medico-legal autopsy cases was wide and the drug was usually found along with other psychoactive drugs. Therefore, although it seems likely that phenazepam contributed to impairment of driving in some DUID cases, the extent of its effect remains unclear and further studies are needed to define the concentrations causing impairment and toxicity. 相似文献
37.
Meghan Prusinowski PhD Pedram Tavadze PhD Zachary Andrews MS Logan Lang BS Divyanjali Pulivendhan BS Cedric Neumann PhD Aldo H. Romero PhD Tatiana Trejos PhD 《Journal of forensic sciences》2024,69(2):498-514
A physical fit is an important observation that can result from the forensic analysis of trace evidence as it conveys a high degree of association between two items. However, physical fit examinations can be time-consuming, and potential bias from analysts may affect judgment. To overcome these shortcomings, a data analysis algorithm using mutual information and a decision tree has been developed to support practitioners in interpreting the evidence. We created these tools using data obtained from physical fit examinations of duct tape and textiles analyzed in previous studies, along with the reasoning behind the analysts' decisions. The relative feature importance is described by material type, enhancing the knowledge base in this field. Compared with the human analysis, the algorithms provided accuracies above 90%, with an improved rate of true positives for most duct tape subsets. Conversely, false positives were observed in high-quality scissor cut (HQ-HT-S) duct tape and textiles. As such, it is advised to use these algorithms in tandem with human analysis. Furthermore, the study evaluated the accuracy of physical fits when only partial sample lengths are available. The results of this investigation indicated that acceptable accuracies for correctly identifying true fits and non-fits occurred when at least 35% of a sample length was present. However, lower accuracies were observed for samples prone to stretching or distortion. Therefore, the models described here can provide a valuable supplementary tool but should not be the sole means of evaluating samples. 相似文献
38.
39.
Fluorescence Imaging of Posterior Spiracles from Second and Third Instars of Forensically Important Chrysomya rufifacies (Diptera: Calliphoridae), 下载免费PDF全文
Danielle Flores M.S. Amy L. Miller M.S. Angelique Showman M.S. Caitlyn Tobita Lori M. N. Shimoda B.S. Carl Sung B.S. Alexander J. Stokes Ph.D. Jeffrey K. Tomberlin Ph.D. David O. Carter Ph.D. Helen Turner Ph.D. 《Journal of forensic sciences》2016,61(6):1578-1587
Entomological protocols for aging blowfly (Diptera: Calliphoridae) larvae to estimate the time of colonization (TOC) are commonly used to assist in death investigations. While the methodologies for analyzing fly larvae differ, most rely on light microscopy, genetic analysis, or, more rarely, electron microscopy. This pilot study sought to improve resolution of larval stage in the forensically important blowfly Chrysomya rufifacies using high‐content fluorescence microscopy and biochemical measures of developmental marker proteins. We established fixation and mounting protocols, defined a set of measurable morphometric criteria and captured developmental transitions of 2nd instar to 3rd instar using both fluorescence microscopy and anti‐ecdysone receptor Western blot analysis. The data show that these instars can be distinguished on the basis of robust, nonbleaching, autofluorescence of larval posterior spiracles. High‐content imaging techniques using confocal microscopy, combined with morphometric and biochemical techniques, may therefore aid forensic entomologists in estimating TOC. 相似文献
40.