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911.
How can we measure whether national institutions in general, and regulatory institutions in particular, are dysfunctional? A central question is whether they are helping a nation's citizens to live good lives. A full answer to that question would require a great deal of philosophical work, but it should be possible to achieve an incompletely theorized agreement on a kind of nonsectarian welfarism, emphasizing the importance of five variables: subjective well‐being, longevity, health, educational attainment, and per capita income. In principle, it would be valuable to identify the effects of new initiatives (including regulations) on all of these variables. In practice, it is not feasible to do so; assessments of subjective well‐being present particular challenges. In their ideal form, Regulatory Impact Statements should be seen as Nonsectarian Welfare Statements, seeking to identify the consequences of regulatory initiatives for various components of welfare. So understood, they provide reasonable measures of regulatory success or failure, and, hence, a plausible test of dysfunction. There is a pressing need for improved evaluations, including both randomized controlled trials and ex post assessments.  相似文献   
912.
Experiments were performed to determine the extent of cross‐contamination of DNA resulting from secondary transfer due to fingerprint brushes used on multiple items of evidence. Analysis of both standard and low copy number (LCN) STR was performed. Two different procedures were used to enhance sensitivity, post‐PCR cleanup and increased cycle number. Under standard STR typing procedures, some additional alleles were produced that were not present in the controls or blanks; however, there was insufficient data to include the contaminant donor as a contributor. Inclusion of the contaminant donor did occur for one sample using post‐PCR cleanup. Detection of the contaminant donor occurred for every replicate of the 31 cycle amplifications; however, using LCN interpretation recommendations for consensus profiles, only one sample would include the contaminant donor. Our results indicate that detection of secondary transfer of DNA can occur through fingerprint brush contamination and is enhanced using LCN‐DNA methods.  相似文献   
913.
The AmpF?STR Yfiler PCR Amplification (Yfiler) kit continues to be improved for a better analytical efficiency in cases of highly degraded DNA. The authors endeavored to determine whether coupling of the Yfiler kit with supplemental multiplex amplification of some Y‐STR loci is a more efficient analytical mode for poorly preserved human femurs (n = 15) discovered at Korean archeological sites. To reveal locus profiles not easily obtained by Yfiler analysis, custom‐designed primers were adopted for the DYS390, DYS391, DYS392, DYS438, DYS439, and DYS635 loci. The success rate for 16 Y‐STR locus profiles obtained from the 15 femurs was improved from 18.33% (in the use of Yfiler kit only) to 49.17% (the coupled use of Yfiler and custom‐designed primers). In this study, the authors established that the custom‐designed primers offer a markedly improved success rate for obtainment of Y‐STR profiles from degraded aDNA not easily identified by sole use of the Yfiler assay.  相似文献   
914.
This study discusses the results of an evaluation of a one‐part blue light‐curing acrylic resin for embedding trace evidence prior to the preparation of thin sections with a microtome. Through a comparison to several epoxy resins, the physical properties relevant to both trace evidence examination and analytical microscopy in general, including as viscosity, clarity, color, hardness, and cure speed, were explored. Finally, thin sections from paint samples embedded in this acrylic resin were evaluated to determine if, through smearing or impregnation, the resin contributed to the infrared spectra. The results of this study show that blue light‐curing acrylic resins provide the desired properties of an embedding medium, generate high‐quality thin sections, and can significantly simplify the preparation of paint chips, fibers and a multitude of other types of microscopic samples in the forensic trace evidence laboratory.  相似文献   
915.
This study applied a decision‐making perspective to examine the causal mechanisms underlying the relation between violent victimization and offending. We theorized that having been victimized affects an individual's appraisal of subsequent potentially conflictive situations in such a way that victims become more attuned toward the benefits of violence perpetration than toward its costs. Furthermore, we argued that this altered appraisal mediates the relation between violent victimization and violent offending. We tested these hypotheses by using data from the Zurich Project on the Social Development of Children and Youths, a longitudinal study of Swiss youth (N = 1,013; 11–15 years of age). In line with expectations, path analysis results showed that prior victimization influenced the appraisal of decision‐making situations that, in turn, predicted subsequent self‐reported violent offending. Importantly, these mediation effects held when controlling for a variety of time‐stable factors, such as self‐control and risky activities, as well as prior victimization and delinquency. Implications for research and theorizing on the victim–offender overlap are elaborated in the discussion.  相似文献   
916.
The detection of semen in forensic investigation is considered important evidence of sexual assault. In this study, we report the development of a real‐time polymerase chain reaction‐based method for identifying semen that can simply and rapidly analyze the semen‐specific unmethylated region of the DACT1 gene. Using two fluorescent probes designed for the methylated or unmethylated status, this method could perform quantitative analysis of the methylation status in this region. Furthermore, this method was used to analyze various body fluid samples, including 29‐year‐old semen and blood stains. The results showed that this method can detect almost exclusively semen or nonsemen signals even in highly decomposed samples, while a few semen or nonsemen samples showed slight signals of the other fluorescence probe. Although there is still a need for further analysis such as setting thresholds to analyze unknown samples, this method could be a useful supplementary tool for identifying semen, especially in old stains such as those in cold‐case investigations.  相似文献   
917.
A mechanical device that uses gravitational and spring compression forces to create spatter patterns of known impact velocities is presented and discussed. The custom‐made device uses either two or four springs (k1 = 267.8 N/m, k2 = 535.5 N/m) in parallel to create seventeen reproducible impact velocities between 2.1 and 4.0 m/s. The impactor is held at several known spring extensions using an electromagnet. Trigger inputs to the high‐speed video camera allow the user to control the magnet's release while capturing video footage simultaneously. A polycarbonate base is used to allow for simultaneous monitoring of the side and bottom views of the impact event. Twenty‐four patterns were created across the impact velocity range and analyzed using HemoSpat. Area of origin estimations fell within an acceptable range (ΔXav = ?5.5 ± 1.9 cm, ΔYav = ?2.6 ± 2.8 cm, ΔZav = +5.5 ± 3.8 cm), supporting distribution analysis for the use in research or bloodstain pattern training. This work provides a framework for those interested in developing a robust impact device.  相似文献   
918.
A novel screening method for shed skin cells by detecting Staphylococcus epidermidis (S. epidermidis), which is a resident bacterium on skin, was developed. Staphylococcus epidermidis was detected using real‐time PCR. Staphylococcus epidermidis was detected in all 20 human skin surface samples. Although not present in blood and urine samples, S. epidermidis was detected in 6 of 20 saliva samples, and 5 of 18 semen samples. The ratio of human DNA to S. epidermidisDNA was significantly smaller in human skin surface samples than in saliva and semen samples in which S. epidermidis was detected. Therefore, although skin cells could not be identified by detecting only S. epidermidis, they could be distinguished by measuring the S. epidermidis to human DNA ratio. This method could be applied to casework touch samples, which suggests that it is useful for screening whether skin cells and human DNA are present on potential evidentiary touch samples.  相似文献   
919.
Erythritol tetranitrate (ETN), an ester of nitric acid and erythritol, is a solid crystalline explosive with high explosive performance. Although it has never been used in any industrial or military application, it has become one of the most prepared and misused improvise explosives. In this study, several analytical techniques were explored to facilitate analysis in forensic laboratories. FTIR and Raman spectrometry measurements expand existing data and bring more detailed assignment of bands through the parallel study of erythritol [15N4] tetranitrate. In the case of powder diffraction, recently published data were verified, and 1H, 13C, and 15N NMR spectra are discussed in detail. The technique of electrospray ionization tandem mass spectrometry was successfully used for the analysis of ETN. Described methods allow fast, versatile, and reliable detection or analysis of samples containing erythritol tetranitrate in forensic laboratories.  相似文献   
920.
To understand the mortality patterns among drug users and potential risk factors, we evaluated drug‐related deaths reported to the Florida Medical Examiners Commission from 2001 to 2013, by substances, demographics, and manner of death. The annual drug‐related fatalities increased by 57% from 2001 to 2013 (total n = 100,882); 51.8% were accidental, 7.9% homicide, 18.6% natural, and 19.6% suicide. The different manners of death exhibited distinct demographic profiles and drug composition. The gender gap was more prominent in homicide. Age ≥55 years was more closely associated with natural death and suicide. Age <35 years and central nervous system (CNS) stimulants including amphetamines and cocaine showed higher relative risks for accidental death and homicide, whereas CNS depressants including benzodiazepines, carisoprodol, opioids, and zolpidem were more strongly associated with accidental death and/or suicide. The findings aid in identifying populations more vulnerable to drug‐related deaths, developing targeted interventions and thereby improving efficiency of preventive efforts.  相似文献   
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