A traffic accident caused by fatigue failure of axle

An investigation of a traffic accident involving a tractor-trailer and a passenger car that were traveling at high speed is presented. The cause was the fracture of a trailer axle. The investigation showed that the fracture was because of the fatigue failure. In addition, cracks were found in the remaining three trailer wheels. Hardness measurements showed that, because of inadequate heat treatment of the metal, they were prone to failure.     

Cross-examination of liquid-liquid extraction (LLE) and solid-phase microextraction (SPME) methods for impurity profiling of methamphetamine

Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results.     

Weapon Use in Korean Homicide: Differences Between Homicides Involving Sharp and Blunt Instruments

On the basis of information regarding 276 homicides committed in South Korea between 1987 and 2008, we compared offenders’ and victims’ characteristics, injury locations, weapon‐related behavior, and offending behavior between homicides involving sharp and blunt instruments. The victims of sharp‐force homicide were much younger relative to those of blunt‐force homicide. In addition, homicides involving blunt instruments were more likely to be committed by offenders who lived with the victims. Most sharp‐force homicides involved injuries to the torso, while blunt‐force homicides involved mainly head injuries. Furthermore, perpetrators of sharp‐force homicides tended to preselect their weapons, while those of blunt‐force homicides were likely to use weapons of opportunity. Logistic regression analysis identified a number of factors, including injury location and body transportation, which significantly predicted weapon type. As this was the first South Korean study to compare sharp‐ and blunt‐force homicides, the results have practical implications for homicide investigations.     

A case study in public child welfare: county-level practices that address racial disparity in foster care placement

Racial disproportionality has been a longstanding issue within child welfare. The continued overrepresentation of black children in the foster care system is troubling. The authors of this article conducted a case study of two counties in New York State that have steadily decreased the number of black children in foster care in an effort to identify what aspects of their child welfare practice impacted the decline. The case study employed document analysis, in-depth interviews, and focus groups with child removal decision makers. Utilizing a grounded theory approach to content organization and analysis, several themes emerged as noticeable factors. Some of the most salient themes included preventive services and resources, community collaborations, case practice development, family meetings, workforce diversity, the court system, and, the most unique, blind removal meetings. The themes found in this study present promising practices to assist in decreasing the racial disparity in child welfare removal decisions.     

Electoral Competition and Agricultural Support in OECD Countries

Agricultural trade protectionism in developed countries remains a politically charged issue, yet few studies have attempted to explain the political dynamics behind this important trade issue. We consider agricultural subsidies as a type of distributive policy that targets the agricultural sector at the expense of consumers and taxpayers. Based on Cox (1987, 1990) and Myerson (1993) , we argue that electoral systems that encourage politicians to appeal to a narrow constituency tend to have a higher level of agricultural support. We test this theoretical hypothesis using OECD agricultural support data disaggregated by commodity and country. A cross-classified multilevel model is employed to account for complex variation of agricultural support across countries, commodities, and time. Our empirical results show that electoral systems that encourage politicians to target narrow (broad) constituencies are associated with relatively high (low) levels of agricultural subsidies.     

Evaluation of DNA match probability in criminal case

The new emphasis on quantification of evidence has led to perplexing courtroom decisions and it has been difficult for forensic scientists to pursue logical arguments. Especially, for evaluating DNA evidence, though both the genetic relationship for two compared persons and the examined locus system should be considered, the understanding for this has not yet drawn much attention. In this paper, we suggest to calculate the match probability by using coancestry coefficient when the family relationship is considered, and thus the performances of the identification values depending on the calculation of match probability are compared under various situations.     

Quantification of propane in biological materials by head-space GC

Propane was measured in specimens taken from two persons who died from a LPG explosion in an apartment using head-space-GC/FID. Because of the variation of instrument performance and sample injection, the internal standard pentane was used. Calibration standards were prepared by injecting each calculated volume of pure propane gas into capped vials containing 2 ml of blood and 5 microl of internal standard. The calibration curve revealed good linearity from 0.09 microg/ml to at least 90 microg/ml. The method validation data also included repeatability and recovery. The propane quantities in blood, fat and brain tissue were between 0.27 and 71 microg/ml (microg/g) with the highest concentration observed in fat. The confirmation of propane was conducted by the means of solid phase micro-extraction and mass spectrometry.