Commentary on “Evaluation of shooting distance by AFM and FTIR⁄ATR analysis of GSR” Mou Y., Lakadwar J., Rabalais J.W., J. Forensic Sci. 2008; 53:1381-6

This piece highlights the disadvantages of utiising atomic force microscopy (AFM) for analysis of gun shot residue (GSR) and other fine powders. Also outlined is the origin of novel particle shapes that can be found in some published images

Burnt to memory: Data extraction from heat damaged mobile phones

Data is retained in SIM card devices that are subjected to temperatures which exceed those likely to be experienced in house fires. In some cases the data is retrievable by rebuilding severed connections; however, in the majority of instances, chips will suffer additional damage to the top surface or circuitry, or experience some mechanical damage. In these cases, although the data is retained in the memory, it cannot be read by conventional methods, and an alternative technique, such as direct probing of the stored charge, needs to be employed to access the retained data

In Diamond Health

In contrast to the sparkling gemstone, diamond-like carbon (DLC) is a thin film coating that is dense, inert, low friction and hard wearing. Interdisciplinary research, involving materials scientists, physicists, mechanical engineers, biomedical specialists and clinicians, is continuously expanding the potential and applications of DLC and enhanced carbon-based materials in the medical sector

Effect of substrate surface topography on forensic development of latent fingerprints with iron oxide powder suspension

This is a pre-print version of the article. The official published version can be accessed from the link below - Copyright @ 2010 Wiley-BlackwellLatent fingerprint deposition and effectiveness of detection are strongly affected by the surface on which prints are deposited. Material properties, surface roughness, morphology, chemistry and hydrophobicity can affect the usefulness or efficacy of forensic print development techniques. Established protocols outline appropriate techniques and sequences of processes for broad categories of operational surfaces. This study uses atomic force microscopy and scanning electron microscopy to investigate a series of surfaces classified as smooth, non-porous plastic. Latent prints developed with iron oxide powder suspension are analysed on a range of scales from macro to nano to help elucidate the interaction mechanisms between the latent fingerprint, development agent and underlying surface. Differences between surfaces have a strong effect, even within this single category. We show that both average roughness and topographical feature shape, characterised by skew, kurtosis and lay, are important factors to consider for the processing of latent fingerprints. Copyright (C) 2010 John Wiley & Sons, Ltd.This work is part-funded by the UK Home Office project 7088762

Exposure variability and behaviour of indoor and outdoor air pollutants in primary schools in the United Kingdom

Copyright @ 2011 ISEEBackground and Aims: Current evidence suggests that exposure to common indoor air pollutants is associated with adverse health effects in children. This study was conducted to examine air quality in four primary schools in southern England, in order to establish daily, weekly and seasonal variability of pollutant concentrations within and between the schools, and to understand the behaviour of common indoor and outdoor air pollutants. Methods: Four primary schools were selected for the study, in urban, suburban and rural environments with diverse size and socioeconomic backgrounds. Air quality monitoring was conducted in three rounds (autumn, winter, summer) during the academic year 2009-2010. Each round involved monitoring continuously for one week in four locations of typical children’s exposure: generally three indoors and one outdoors. Measurements were carried out for particulate matter count for size range 0.5-5.0μm (PM0.5-5.0), carbon dioxide (CO2), carbon monoxide (CO), and nitrogen dioxide (NO2). Results: Findings revealed great variability in PM0.5-5.0 concentrations during the week and between rounds of measurements within each school, and between schools. CO concentrations were greatly variable for the suburban and rural schools. Little variability was seen for NO2 concentrations. CO2 levels differed during the day and between days and rounds in each school, and between schools, depending on the daily activity patterns of children and practice of ventilation. Linear regression models predicted indoor levels for PM0.5-5.0, CO and NO2, based on contribution of outdoor concentrations to the same pollutant, ventilation measured by CO2 concentrations and weather variables. Conclusions: Study findings showed variability in pollutant exposure levels between locations, days and seasons in each school, and between all four schools. These differences related to school building design and location, ventilation practices and children’s daily activities. These findings support the need for developing methodology for personal exposure assessment to air pollutants among school children

The Geography of Open Dumps in Rural Appalachia

The dumping of waste into the environment has plagued the mountains of Rural Appalachia for decades. Tire, cars, appliances, and drug producing materials routinely are illegally disposed of via open dumps. The purpose of this research is to reveal the motives of the damaging open dumpsites that damage the beauty of the Appalachian Mountains. The states of Kentucky and West Virginia were analyzed through the use of GIS and descriptive statistics. The distance to refuse centers and application of disposal fees are the leading factors that result to the use of open dumps

Effect of sintering temperature and heat treatment on electrical properties of indium oxide based ceramics

Indium oxide based ceramics with bismuth oxide addition were sintered in air in the temperature range 800-1300 ºC. Current-voltage characteristics of In2O3-Bi2O3 ceramics sintered at different temperatures are weakly nonlinear. After an additional heat treatment in air at about 200 ºC samples sintered at a temperature within the narrow range of about 1050-1100 ºC exhibit a current-limiting effect accompanied by low-frequency current oscillations. It is shown that the observed electrical properties are controlled by the grain-boundary barriers and the heat treatment in air at 200 ºC leads to the decrease in the barrier height. Electrical measurements, scanning electron microscopy and X-ray photoelectron spectroscopy results suggest that the current-limiting effect observed in In2O3-Bi2O3 can be explained in terms of the modified barrier model proposed earlier for the explanation of similar effect in In2O3-SrO ceramics

Electronic properties of SnO2-based ceramics with double function of varistor and humidity sensor

This is the post-print version of the article. The official published version can be obtained from the link below - Copyright @ 2010 AD-Tech.Tin dioxide based varistor ceramics SnO2-Co3O4-Nb2O5-Cr2O3-xCuO (x=0; 0.05; 0.1 and 0.5) were made and their electrical properties were studied. The highest nonlinearity coefficient and electric field (at current density 10-3 A cm-2) were obtained for 0.1 mol.% CuO addition. It was observed that low-field electrical conductivity is increased with relative humidity, therefore, materials obtained exhibit double function of varistor and humidity sensor. The highest humidity sensitivity coefficient is found for SnO2-Co3O4-Nb2O5-Cr2O3 ceramics (without CuO). Observed varistor and humidity-sensitive properties are explained in the frames of grain-boundary double Schottky barrier concept as a decrease of the barrier height with electric field or relative humidity. Using suggested simple theory and data obtained on isothermal capacitance relaxation, the energy of the grain-boundary monoenergetic trapping states were estimated. These values are less than found for activation energy of electrical conduction (as a measure of the barrier height). These observations confirm the barrier concept.This work is funded by the Royal Society, United Kingdom (2007R1/R26999)