Soil forensics: How far can soil clay analysis distinguish between soil vestiges?

Soil traces are useful as forensic evidences because they frequently adhere to individuals and objects associated with crimes and can place or discard a suspect at/from a crime scene. Soil is a mixture of organic and inorganic components and among them soil clay contains signatures that make it reliable as forensic evidence. In this study, we hypothesized that soils can be forensically distinguished through the analysis of their clay fraction alone, and that samples of the same soil type can be consistently distinguished according to the distance they were collected from each other. To test these hypotheses 16 Oxisol samples were collected at distances of between 2 m and 1.000 m, and 16 Inceptisol samples were collected at distances of between 2 m and 300 m from each other. Clay fractions were extracted from soil samples and analyzed for hyperspectral color reflectance (HSI), X-ray diffraction crystallographic (XRD), and for contents of iron oxides, kaolinite and gibbsite. The dataset was submitted to multivariate analysis and results were from 65% to 100% effective to distinguish between samples from the two soil types. Both soil types could be consistently distinguished for forensic purposes according to the distance that samples were collected from each other: 1000 m for Oxisol and 10 m for Inceptisol. Clay color and XRD analysis were the most effective techniques to distinguish clay samples, and Inceptisol samples were more easily distinguished than Oxisol samples. Soil forensics seems a promising field for soil scientists as soil clay can be useful as forensic evidence by using routine analytical techniques from soil science.     

Further Validation of the Test of Memory Malingering (TOMM) Trial 1 Performance Validity Index: Examination of False Positives and Convergent Validity

Assessment of performance validity is an essential part of a neuropsychological evaluation, with the inclusion of two or more performance validity tests (PVTs) becoming routine practice. Considering the time to administer multiple tests, there has been some support for use of the Test of Memory Malingering (TOMM) Trial 1 (T1) as an independent, “one and done” PVT. Notably, cutoffs for TOMM T1 need further validation, with an emphasis on minimizing false-positive classifications among those with bona fide cognitive impairment. In a clinically referred sample of 127 veterans, this study examined the role of cognitive impairment in TOMM performance and the utility of a TOMM T1 as an independent PVT. Examinees were administered the TOMM and three additional PVTs as part of a comprehensive neuropsychological battery. Sixty-eight percent of examinees were classified valid (35% of valid examinees were cognitively impaired). TOMM T1?≤?40 had excellent observed sensitivity (83%) and specificity (93%) overall, with minimal false-positive classification. TOMM T1 was also significantly correlated and concordant with other memory-based PVTs. Given score ranges and failure rates for TOMM T1?≤?40 among those with neurological/neurocognitive conditions, scores in the 37–40 range may merit administration of additional TOMM trials to maximize accuracy in identifying valid-cognitively impaired versus noncredible performance. Otherwise, an abbreviated TOMM administration (i.e., only T1) using a cutoff of ≤?40—in conjunction with one or more additional PVTs—may be sufficient for detecting noncredible/invalid test performance in the absence of known or suspected neurological/neurocognitive disorders.     

The North‐South dialogue revisited: Some personal reflections

This article focuses on the experiences of South Korea and the Philippines and examines the relationship of corruption to political and economic development. It argues that corruption is a manifestation of specific sets of state-society relations, political systems, development trajectories and types of external linkages. Corruption in these contexts should not be seen as pathological phenomena but as deeply integrated into the particular path of political and economic development. The article further identifies the context and scope for reform.     

Is overpunishment fairer than underpunishment? Perceptions of deviations from equity

Abstract

Three studies are presented which test hypotheses derived from Equity Theory, Prospect Theory and the principle of Diminishing Marginal Value with regard to preferences for overpunishment and underpunishment in the assignment of penalties to offences of varying severity. The first two studies showed that, with different subject samples, offences, and kinds of punishments, subjects indicated a marked preference for over-punishment rather than underpunishment, when both over punishment and under-punishment deviated from ideal, or equitable, punishment to the same degree. However, the effect was only apparent for serious offences. A third study showed that the overpunishment preference for a serious offence existed even when the overpunishment deviated 30% more from ideal punishment than underpunishment, but again no preference was shown' for the less serious offence. As the results cannot be readily explained in terms of any of the three explanatory principles, a possible explanation in terms of concept of negative reciprocity is advanced.     

Morphometry of latent palmprints as a function of time

In many crimes, the elapsed time between production and collecting fingermark traces is crucial. and a method able to detect the aging of latent prints would represent an improvement in forensic procedures. Considering that as the latent print gets older, substantial changes in the relative proportion of individual components secreted by skin glands could affect the morphology of ridges, morphometry could be a potential tool to assess the aging of latent fingermarks. Then, considering the very limited research in the field, the present work aims to evaluate the morphometry of latent palmprint ridges, as a function of time, in order to identify an aging pattern. The latent marks were deposited by 20 donors on glass microscope slides considering pressure and contact angle, and then were maintained under controlled environmental conditions. The morphometric study was conducted on marks developed with magnetic powder in 7 different time intervals after deposition (0, 5, 10, 15, 20, 25 or 30 days); 60 ridges were evaluated for each developed mark. The results showed that: 1) the method for the replacement and mixing of skin secretions on the palm was appropriate to ensure reproducibility of latent prints, and 2) considering the studied group, there was a time-dependent reduction in the width of ridges and on the percentage of visible ridges over 30 days. Results suggest the possibility of using the morphometric method to determine an aging profile of latent palmprints on glass surface, aiming for forensic purposes.     

Impacts of housing and mortgage market discrimination racial and ethnic disparities in homeownership

Abstract

There are persistent differences in homeownership rates across racial and ethnic groups. Homeownership rates for whites are over 20 percentage points higher than for blacks or Hispanics. This paper uses a model of the housing tenure decision to gain a better understanding of these racial and ethnic differentials in homeownership and employs a decomposition technique that has been applied to labor market discrimination to report the results of the empirical testing of two hypotheses: (1) race (ethnicity) influences the probability of ownership through differences in household endowments (income, education, age, gender, and family type) and market endowments (price and location); and (2) race (ethnicity) directly influences the probability of ownership through racial or ethnic discrimination and other factors that may be correlated with race or ethnicity.

We find endowment effects important in explaining the persistent racial and ethnic disparities in homeownership. In brief, logit analysis of 1989 American Housing Survey (AHS) national sample data reveals that 81 percent (78 percent) of the differences between the predicted probability of ownership between black and white households (Hispanic/non‐Hispanic) are due to differences in group endowments. Direct effects explain 19 percent of the black‐white differentials and 22 percent of the Hispanic/non‐Hispanic differentials. Because the direct effects are modeled as residual differences, it must be realized that the residual components could also be capturing the influence of important omitted or harder to measure variables internal to the market process and correlated with race or ethnicity. These include wealth, household location, employment history, credit history, and cultural predisposition toward homeownership.