Using Cluster Analysis and ICP‐MS to Identify Groups of Ecstasy Tablets in Sao Paulo State,Brazil

The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples.     

Evaluation of Lip Prints on Different Supports Using a Batch Image Processing Algorithm and Image Superimposition

This study aimed to develop and to assess an algorithm to facilitate lip print visualization, and to digitally analyze lip prints on different supports, by superimposition. It also aimed to classify lip prints according to sex. A batch image processing algorithm was developed, which facilitated the identification and extraction of information about lip grooves. However, it performed better for lip print images with a uniform background. Paper and glass slab allowed more correct identifications than glass and the both sides of compact disks. There was no significant difference between the type of support and the amount of matching structures located in the middle area of the lower lip. There was no evidence of association between types of lip grooves and sex. Lip groove patterns of type III and type I were the most common for both sexes. The development of systems for lip print analysis is necessary, mainly concerning digital methods.     

X‐ray Diffraction and Rietveld Refinement in Deferrified Clays for Forensic Science

Soil vestiges might provide information about a crime scene. The Rietveld method with X‐ray diffraction data (RM‐XRD) is a nondestructive technique that makes it possible to characterize minerals present in the soils. Soil clays from the metropolitan region of Curitiba (Brazil) were submitted to DCB treatment and analyzed using XRD with CuK_α radiation in the step‐scan mode (0.02° 2θ/5 s). The GSAS+EXPGUI software was used for RM refinement. The RM‐XRD results, together with the principal component analysis (PCA) (52.6% total variance), showed the kaolinite predominance in most analyzed samples and the highest quartz contents in “site 1.” Higher anatase, and gibbsite and muscovite contents influenced discrimination, mainly in “site 3” and “site 1,” respectively. These results were enough to discriminate clays of four sites and two horizons using a reduced amount of sample showing that the technique can be applied to the investigation into soil vestiges.     

Economic status,religion, and demography in an Ulster town in the early twentieth century

The paper offers an analysis of the demography of the confessionally-divided and heavily industrialized northern Irish town of Lurgan in the early twentieth century. Its main source is the individual household forms of the Irish population census of 1911. This was the first Irish census to provide household-level data on the number of children born—and the number still surviving—to married couples co-resident at the time of the census. The paper begins by producing standard cross-tabulations of socio-economic status, as represented by literacy, numeracy, occupation, and the labour force participation of married women, by religion. It then presents econometric analyses of female labour force participation, marital fertility, and infant and child mortality. The greater poverty of Catholic households forced a higher proportion of mothers to work outside the home, mainly as unskilled workers in the town's linen mills. The analysis of the marital fertility suggests that confessional affiliation did not influence family size much at this juncture. The analysis of infant and child mortality suggests that religious affiliation was to a significant extent a cloak for living standards and socio-economic advantage.     

Veni,vidi, vici: postcolonial studies comes of age

This review article offers a critical assessment of Ato Quayson's Cambridge History of Postcolonial Literature (2012), engaging in passing with a debate between postcolonial theorists that appeared also in 2012 in the New Literary History (43.1 & 2). It posits that the History presents postcolonial literature, and indeed postcolonial studies, as much too settled fields, a view clearly at odds both with their genesis and with that reflected in the essays in NLH.     

The black soldier-fly, Hermetia illucens (Diptera, Stratiomyidae), used to estimate the postmortem interval in a case in Amapá State, Brazil

The black soldier-fly (Hermetia illucens) is a generalist detritivore which is commonly present in corpses in later stages of decomposition and may be useful in forensic entomology. This paper describes the estimation of the postmortem interval (PMI) based on the life cycle of the black soldier-fly in a case in northern Brazil. A male child was abducted from his home and 42 days later his corpse was found in an advanced stage of decay. Two black soldier-fly larvae were found associated with the body. The larvae emerged as adults after 25-26 days. Considering the development cycle of H. illucens, the date of oviposition was estimated as 24-25 days after abduction. Since H. illucens usually (but not always) colonizes corpses in more advanced stages of decay, this estimate is consistent with the hypothesis that the child was killed immediately after abduction.     

A model of local crime displacement

In this paper, we develop a two-region model of crime spatial displacement. For high crime regions, the crime rate in one locality is negatively influenced by the crime rate of the other. The magnitude of the displacement depends on the distance between the two regions and on their relative size. For given sized neighbors, a closer distance implies greater displacement. When one region is larger, relative to the other, this increases the displacement, holding distance fixed. Examples show that the displacement from the treated to the adjacent areas can be small, if the relative size of the former is small. Nonetheless, the displacement can be large for other nearby areas, provided that the treated region is relatively big. Neglecting this result can cause an upward bias at the estimated impact of a policy. We also analyze the consequences for the design of public policies.     

Demystifying "oxi" cocaine: Chemical profiling analysis of a "new Brazilian drug" from Acre State

Recent information from various sources suggests that a new illicit drug, called "oxi", is being spread across Brazil. It would be used in the smoked form and it would look like to crack cocaine: usually small yellowish or light brown stones. As fully released in the media, "oxi" would differ from crack cocaine in the sense that crack would contain carbonate or bicarbonate salts whereas "oxi" would include the addition of calcium oxide and kerosene (or gasoline). In this context, this work presents a chemical profiling comparative study between "oxi" street samples seized by the Civil Police of the State of Acre (CP/AC) and samples associated with both international and interstate drug trafficking seized by the Brazilian Federal Police in Acre (FP/AC). The outcome of this work assisted Brazilian authorities to stop inaccurate and alarmist releases on this issue. It may be of good use by the forensic community in order to better understand matters in their efforts to guide local law enforcement agencies in case such claims reach the international illicit market.