The use of filtered light for the evaluation of writing inks analyzed using thin layer chromatography

Thin layer chromatography (TLC) is a scientific methodology that can be used to compare and characterize ink formulations. Occasionally, when evaluating chromatographic profiles on a TLC plate with ambient light, different ink formulations, or the same inks from different batches, may appear indistinguishable. The use of filtered light can be very effective to illuminate characteristics that are not readily apparent with ambient light. There are a diverse number of components commonly found in writing inks, and it may be that some of them respond to particular wavelengths of energy that are not visible to the unaided eye (i.e., colorless). There has been very little information published that addresses the use of filtered light for evaluating TLC plates. Twenty-nine ballpoint writing ink samples were selected for TLC analysis. Further evaluation using an alternate light source, coupled with the appropriate filter, proved to be an effective means for definitive discrimination in some cases.     

Criteria for the interpretation of cocaine levels in human biological samples and their relation to the cause of death

The determination that cocaine is directly responsible for the immediate cause of death should be considered only when there is a reasonably complete understanding of the circumstances or facts surrounding the death. Another, more obvious and immediate cause of death must be absent, or, at least cocaine must be shown to be a significant contributing factor in the chain of medical findings that lead directly to the immediate cause of death. Not all death investigation requires the sequential steps described in this paper, but these steps must be considered early on in the investigation whenever there is scene, investigational, medical or a historical basis to believe that cocaine is directly related to the cause of death. A relatively high profile death when cocaine is known to be involved, or a death involving unusual behavior on the part of the deceased with police involvement are examples where these considerations may well apply. Information needs to be obtained as soon as possible to have the highest chance of successfully documenting the toxicologic basis for the diagnosis. These facts would include, but would not necessarily be limited to, a scene investigation (whenever possible), a careful review of the investigative reports from all involved agencies, the initial core temperature of the body as well as that of the environment at the time of the collapse or death, the past medical history of the individual, and the results of a complete forensic autopsy and toxicologic studies. Knowledge of and an understanding of the current relevant forensic literature on this subject should be available to the reviewer prior to any interpretation of the significance of cocaine upon a specific death.     

A fatal maprotiline intoxication

A fatal maprotiline intoxication is presented. The postmortem anatomical and toxicologic findings are discussed, as is the mechanism of maprotiline toxicity. This report is, to the best of our knowledge, the sixth fatal maprotiline poisoning in the medical literature.     

Capturing high-resolution digital images for use in forensic document examination

In the past, pattern disciplines within forensic science have periodically faced criticism due to their subjective and qualitative nature and the perceived absence of research evaluating and supporting the foundations of their practices. Recently, however, forensic scientists and researchers in the field of pattern evidence analysis have developed and published approaches that are more quantitative, objective, and data driven. This effort includes automation, algorithms, and measurement sciences, with the end goal of enabling conclusions to be informed by quantitative models. Before employing these tools, forensic evidence must be digitized in a way that adequately balances high-quality detail and content capture with minimal background noise imparted by the selected technique. While the current work describes the process of optimizing a method to digitize physical documentary evidence for use in semi-automated trash mark examinations, it could be applied to assist other disciplines where the digitization of physical items of evidence is prevalent. For trash mark examinations specifically, it was found that high-resolution photography provided optimal digital versions of evidentiary items when compared to high-resolution scanning.     

Shape-shifting Around the Maternal: A Response

ABSTRACT

This article provides a considered response to all the contributions in this special issue on ‘Refiguring the Postmaternal’. It reflects on the new possibilities of postmaternalism as advanced and extended by each contributing author. It also attempts to reassert the idea of the postmaternal as a cultural anxiety about care and dependency and the need for ‘maternal thinking’. These are reinforced as important interpretive frames, while at the same time as paying particular attention to the limitations of these conceptions. Some of the recent literature on maternalism is discussed and this in turn raises questions about the widespread feminist discomfort around maternalism and its many historical and contemporary associations. A notion of the maternal as limit is introduced as a possible rich area for further investigation. The article ends with some policy examples of what a re-maternalised public sphere might look like. It calls for a cultural remembering of maternalist activism, alongside striving to develop alternative feminist visions for these postmaternal times.     

The Classification of Inkjet Inks Using AccuTOF™ DART™ (Direct Analysis in Real Time) Mass Spectrometry—A Preliminary Study

A novel approach for the analysis of inkjet inks is being reported. A time‐of‐flight mass spectrometer, coupled with a Direct Analysis in Real Time (DART?) ion source (AccuTOF? DART?), was used to determine if inkjet inks from various manufacturers and models of printers could be reliably differentiated, characterized, and identified. A total of 217 ink standards were analyzed. As inkjet printing often involves the use of multiple colors (e.g., cyan, magenta, yellow, and black) to form an image or text, two different approaches to creating a library of standards and sampling methods were evaluated for implementation in a standard operating procedure. This research will show that a microscopic examination of the region of interest is requisite to identify what colors were utilized during the printing process, prior to comparing with known standards. Finally, blind testing was administered with 10 unknown samples to assess the validity and accuracy of the methodology.     

Demographic, pathologic, and toxicological profiles of 127 decedents testing positive for ephedrine alkaloids

The relative toxicity of ephedra-containing dietary supplements is disputed. In order to ascertain the magnitude of the problem, we reviewed all autopsies in our Medical Examiner's jurisdiction, from 1994 to 2001, where ephedrine or any its isomers (E+) were detected. Toxicology testing results were tabulated and anatomic findings in E+ cases were compared to those in a control group of drug-free trauma victims. Of 127 E+ cases identified, 33 were due to trauma. Decedents were mostly male (80.3%) and mostly Caucasian (59%). Blood ephedrine concentrations were <0.49 mg/l in 50% of the cases, range 0.07-11.73 mg/l in trauma victims, and 0.02-12.35 mg/l in non-trauma cases. Norephedrine (NE) was present in the blood of 22.8% (mean of 1.81 mg/l, S.D.=3.14 mg/l) and in the urine of 36.2% (mean of 15.6 mg/l, S.D.=21.50mg/l). Pseudoephedrine (PE) was present in the blood of 6.3% (8/127). More than 88% (113/127) of the decedents also tested positive for other drugs, the most common being cocaine (or its metabolites) and morphine. The most frequent pathologic diagnoses were hepatic steatosis (27/127) and nephrosclerosis (22/127). Left ventricular hypertrophy was common, and coronary artery disease (CAD) detected in nearly one third of the cases. The most common findings in E+ deaths are those generally associated with chronic stimulant abuse, and abuse of other drugs was common in those with CAD. There were no cases of heat stroke or rhabdomyolysis. In most cases, norephedrine was not detected, suggesting it plays no role in ephedrine toxicity.