High-performance liquid chromatography-ultraviolet-visible spectroscopy-electrospray ionization mass spectrometry method for acrylic and polyester forensic fiber dye analysis

A critical point of comparison between a fiber collected from a crime scene and a fiber from a known source is the color. Fiber dye analysis using thin-layer chromatography or ultraviolet (UV)-visible (Vis) microspectrophotometry provides useful, although limited, data for comparison. High-performance liquid chromatography-electrospray ionization mass spectrometry (LC/MS) overcomes these limitations by integrating chromatography, ultraviolet-visible spectroscopy, and mass spectrometry into a single instrument. In order to evaluate the applicability of the LC/MS to forensic fiber dye analysis, a multi-stage chromatographic method using acidified water and acidified acetonitrile was developed that separated and identified a mixture of 15 basic and 13 disperse dye standards. The LC/MS also detected and analyzed dyes extracted from individual 0.5 cm acrylic and polyester fibers, demonstrating its applicability to this type of analysis. With regard to the analysis of disperse dyes in polyester fibers, the replacement of pyridine with acetonitrile in the extraction system allowed direct injection of the extracts into the LC/MS. The advantage of the LC/MS over other instrumental methods of textile dye analysis is demonstrated by the analysis and differentiation of three black acrylic fibers: two fibers had similar UV-Vis spectra but were differentiated with chromatography and two had similar UV-Vis spectra and chromatograms but were differentiated using the mass spectrometer.     

Criminal-thinking styles and illegal behavior among college students: validation of the PICTS

The present study examined the relation of self-reported criminal-thinking styles and self-reported illegal behavior among college students. Participants were 177 male and 216 female (N=393) undergraduate students. Participants were divided by gender and further classified into four groups of self-reported illegal behavior: control-status offenses, drug crimes, property crimes, and violent crimes against people. The psychological inventory of criminal-thinking styles (PICTS) (1) measured criminal-thinking patterns on eight scales. Results indicated that males who committed violent crimes against people endorsed significantly higher levels of distorted criminal-thinking patterns on all scales than the control-status offenses, and drug crimes groups. Interestingly, female participants who committed property crimes displayed six significantly elevated PICTS scales whereas females with violent crimes against people had significant elevations on only four of the criminal-thinking style scales. These results extend Walter's initial validation of the PICTS with incarcerated respondents to a non-incarcerated population and show potential use of the PICTS with other populations.     

Development of a GC-MS method for the simultaneous analysis of latent fingerprint components

Latent fingerprint residue is a complex mixture of organic and inorganic compounds. A full understanding of the composition of this mixture and how it changes after deposition is lacking. Three solvent systems were compared for the simultaneous extraction and derivatization with ethyl chloroformate of selected amino and fatty acids from a nonporous substrate (Mylar for subsequent analysis by gas chromatography-mass spectrometry. A solvent system comprised of sodium hydroxide, ethanol, and pyridine was found to be the most effective. This method was applied to the analysis of latent fingerprint residue deposited on Mylar and preliminary data are presented. Twelve amino acids (e.g., serine, glycine, and aspartic acid) and 10 fatty acids (e.g., tetradecanoic, hexadecanoic, and octadecanoic acids) were identified. The potential application of this method to further the understanding of latent fingerprint chemistry has been demonstrated.     

γ-羟基丁酸在急性中毒大鼠体液和组织中的检测及分布

目的建立生物检材中γ-羟基丁酸(GHB)的检测方法,研究GHB急性中毒大鼠体内GHB的分布,为GHB中毒的鉴定提供方法和评价依据。方法用GC/MS法检测生物检材中的GHB;以1000mg/kg剂量给大鼠灌胃使其染毒,分别于1h和3h处死,测定体液和组织中GHB的含量。结果测组织中内源性GHB的线性范围是1～20μg/g,R2=0.9974;测组织中外源性GHB的线性范围为100～1500μg/g,R2=0.9958。相对回收率为98%～103%。体内内源性GHB的含量均≤10μg/mL或10μg/g。尿液中GHB含量为最高,其他依次为:胃、血液、肠、肾、肺、脾、心、肝和脑。结论所建方法准确、便捷,适用于GHB中毒的鉴定;尿液是体内检测GHB的最佳检材。     

Co‐enforcing Labor standards: the unique contributions of state and worker organizations in Argentina and the United States

Labor inspection is a central response to the tremendous gap between formal regulations and outcomes for workers throughout the world. Scholarly and policy debates on labor regulation have focused on improving the targeting of enforcement, changing strategies of street‐level agents, and creating private alternatives to state regulation. This paper argues that these proposals, while important, fail to systematically incorporate the potential contributions of worker organizations and, as a result, overlook opportunities for co‐enforcing labor standards, a key element of labor inspection. By contrast, we develop a framework to analyze the relationships between worker organizations and state regulators that underpin co‐enforcement. We ground this framework empirically in comparative cases, set in Argentina and the United States, presenting two cases of co‐enforcement in highly different institutional contexts. In so doing, we seek to illuminate key attributes of labor inspection and guide attempts to enhance enforcement by forging partnerships between regulators and worker organizations.     

Injury Pattern as an Indication of Seat Belt Failure in Ejected Vehicle Occupants

Prior authors have suggested that when occupant ejection occurs in association with a seat belt failure, entanglement of the outboard upper extremity (OUE) with the retracting shoulder belt will invariably occur, leaving injury pattern evidence of belt use. In the present investigation, the authors assessed this theory using data accessed from the NASS‐CDS for ejected front seat occupants of passenger vehicles. Logistic regression models were used to assess the associations between seat belt failure status and injuries. Injury types associated with seat belt failure were significant OUE and head injuries (OR = 3.87, [95% CI 1.2, 13.0] and 3.1, [95% CI 1.0, 9.7], respectively). The two injury types were found to be a predictor of seat belt use and subsequent failure only if combined with a high (≥0.8) precrash probability of belt use. The injury pattern associated with a seat belt failure‐related ejection has limited use in the forensic investigation of crash‐related ejections.     

Forensic Analysis of MTBE Contamination Using Basic Hydrogeologic Concepts

Contamination of groundwater with petroleum hydrocarbons and additives, such as methyl tert‐butyl ether (MTBE), is often linked to the leaking product distribution system of gas stations. In very few cases is it know if and when a leak occurred and how much product was released to the environment. In the absence of direct evidence, a careful analysis of the available data, such as contaminant breakthrough at receptor wells or discrepancies in the product inventory data, may provide evidence about the nature of the release, its timing and magnitude. Using a MTBE contamination site in the formerly glaciated New England region as an example, two possible release scenarios (slow, long‐term release vs. spill) were examined. Of the two scenarios, the slow release could be ruled out as the sole source even though there was no direct evidence for a spill. The analysis of hydraulic test results together with chemical data further permitted to estimate when such an undocumented spill might have occurred. Analyses of the data also allowed these results to be compared to that of a prior transport and fate modeling study. Good agreement and consistency for contaminant travel times was confirmed. This forensic analysis demonstrates that applying basic hydrogeologic principles can aide in the reconstruction of contamination events while providing more readily understandable and defendable evidence relative to complex models. Conceptually, the approach described herein is transferable to other sites with similar hydrogeologies.