High Resolution Imaging of Latent Fingerprints by Localized Corrosion on Brass Surfaces

Abstract:  The Atomic Force Microscope (AFM) is capable of imaging fingerprint ridges on polished brass substrates at an unprecedented level of detail. While exposure to elevated humidity at ambient or slightly raised temperatures does not change the image appreciably, subsequent brief heating in a flame results in complete loss of the sweat deposit and the appearance of pits and trenches. Localized elemental analysis (using EDAX, coupled with SEM imaging) shows the presence of the constituents of salt in the initial deposits. Together with water and atmospheric oxygen—and with thermal enhancement—these are capable of driving a surface corrosion process. This process is sufficiently localized that it has the potential to generate a durable negative topographical image of the fingerprint. AFM examination of surface regions between ridges revealed small deposits (probably microscopic "spatter" of sweat components or transferred particulates) that may ultimately limit the level of ridge detail analysis.     

A Comparison of Cleaning Regimes for the Effective Removal of Fingerprint Deposits from Brass

Abstract:  Effective removal of fingerprint deposits is crucial for experimentation related to the corrosion of metals by fingerprint deposits. Such removal is also necessary prior to deposition of test fingerprints. The effectiveness of four regimes in removing fingerprint deposits from brass is considered. Sustained wiping of the deposit with a tissue at applied pressures of up to c . 1430 Pa or rubbing while the brass was immersed in acetone both failed to remove completely all traces of fingerprint deposits. Heating the brass to 600°C was an effective remover; however, this also oxidized the surface of the metal except where inhibited by fingerprint deposits. The most effective regime, and the only one of the four that removed all traces of deposit without affecting the properties of the metal surface, was immersion in warm soapy water while rubbing with a tissue. We propose this as the preferred method for fingerprint removal.     

Using Gas Chromatography with Ion Mobility Spectrometry to Resolve Explosive Compounds in the Presence of Interferents*

Abstract: Ion mobility spectrometry (IMS) is a valued field detection technology because of its speed and high sensitivity, but IMS cannot easily resolve analytes of interest within mixtures. Coupling gas chromatography (GC) to IMS adds a separation capability to resolve complex matrices. A GC‐IONSCAN^® operated in IMS and GC/IMS modes was evaluated with combinations of five explosives and four interferents. In 100 explosive/interferent combinations, IMS yielded 21 false positives while GC/IMS substantially reduced the occurrence of false positives to one. In addition, the results indicate that through redesign or modification of the preconcentrator there would be significant advantages to using GC/IMS, such as enhancement of the linear dynamic range (LDR) in some situations. By balancing sensitivity with LDR, GC/IMS could prove to be a very advantageous tool when addressing real world complex mixture situations.     

Misinterpreting Danger? Stereotype Threat,Pre-attack Indicators,and Police-Citizen Interactions

This paper compares police trainings and materials on pre-attack indicators in police-citizen interactions with similar behavioral indicators of stereotype threat, which is not necessarily a sign of danger. Stereotype threat is a social identity threat in which individuals feel that they may be judged or treated negatively based on a social group stereotype (Steele 1997). This psychological threat can increase the target’s anxiety, physiological arousal, and decrease cognitive capacity. We hypothesize that symptoms of stereotype threat might be similar to pre-attack indicators being taught to police in the USA, which can lead police to potentially misinterpret a citizen’s actions. Using a deductive content analysis, three coders analyzed a sample of pre-attack indicator police trainings for three indicators of stereotype threat: anxiety, arousal, and reduced cognitive capacity. Results found significant overlap between danger indicators taught in trainings and stereotype threat indicators. All 15 identified trainings contained at least one of the three indicators of stereotype threat, and 13 contained at least two indicators. None of the trainings discussed stereotype threat. We argue that stereotype threat should be taught in addition to relevant indicators of danger in trainings, lest officers misinterpret citizens’ stereotype threat-related behaviors solely as manifestations of imminent danger.     

Panel on the Economic and Political Consequences of Chernobyl'

This article summarizes a discussion by a panel of leading experts on Soviet energy analyzing the consequences of the accident at the Chernobyl' nuclear plant in the Ukraine on April 26, 1986.

The near-term economic costs associated with clean-up, relocation, and compensating for losses to electricity supplies are significant but manageable. The longer-term effects will focus on likely modifications in Soviet strategies for the nuclear industry, which may shift emphasis back towards conventional fuels and conservation.

The political consequences were managed fairly well by the leadership. Consistent with Secretary Gorbachev's policy of glasnost' (openness) more information has been available on this event than was the case in previous analogous situations. Journal of Economic Literature, Classification Numbers: 027, 124, 723.     

Gorbachev's Economic Reform: A Soviet Economy Roundtable

The proceedings of a panel of American specialists devoted to the recent economic reform are summarized. The panelists noted that the most substantial changes to date have accompanied efforts to restructure the decisionmaking hierarchy—in particular, a recentralization of authority through the creation of biuros and state committees and legislation on individual economic activity. Changes in the systems of economic planning and incentives, on the other hand, have been minor, suggesting a continuing debate over the extent to which price reform and various economic incentives should be implemented. Journal of Economic Literature, Classification Numbers: 052, 113, 124.     

Resources on East Timor

Abstract

Until recently information in the United States on East Timor and the Indonesian occupation was scarce and usually outdated; more English-language material has been available in Australia and Britain. The wide international distribution of the videotape of the Indonesian Army's massacre of more than 270 innocent Timorese civilians in the Santa Cruz Cemetery (12 November 1991) contributed greatly to increasing international awareness of East Timor's plight. More importantly, the publicity surrounding the massacre revitalized solidarity groups around the world. As the groups expanded, so did the literature on East Timor. It is noteworthy that, aside from a few scholarly works, almost all of the available literature on East Timor has been written by activists of one sort or another.     

‘Look into my eyes’: can an instruction to maintain eye contact facilitate lie detection?

Abstract

Traditionally, research on offender profiling has investigated the relationships between offender behaviour and offender characteristics. However, evidence about offender behaviour is not the only evidence available at a crime scene. This study extends previous collaborative research between forensic scientists and psychologists (e.g. Bond & Sheridan, Journal of Forensic Science, 52, 1122–1128, 2007) to investigate how forensic science can assist in the psychological process of offender profiling. Specifically, the potential utility of footwear impression evidence in the task of offender profiling is investigated. Using 155 domestic burglaries, the consistency and homology assumptions underlying offender profiling were tested. Evidence supportive of both assumptions is reported. A multiple regression analysis identified significant relationships between cost of footwear and employment status, age of offender, and the relative deprivation of his/her residence.     

Introduction to issue number two

“Groen Links (Green Left) is Holland's new, radical, green party, which occupies a space to the left of the Social Democrats. It has been formed through the unification of four smaller left wing parties, and as its name makes clear it involves a conscious attempt at a fusion of red and green politics.”