DNA recovery after sequential processing of latent fingerprints on copy paper

Forensic examiners must determine whether both latent fingerprint development and DNA profiling can be performed on the same area of an evidence item and, if only one is possible, which examination offers the best chance for identification. Latent fingerprints can be enhanced by targeting different components of fingerprint residues with sequential chemical treatments. This study investigated the effects of single-reagent and sequential latent fingerprint development processes on downstream DNA analysis to determine the point at which latent fingerprint development should be stopped to allow for DNA recovery. Latent fingerprints deposited on copy paper by one donor were developed using three sequential processes: 1,8-diazafluoren-9-one (DFO) → ninhydrin → physical developer (PD); 1,2-indanedione-zinc (IND-Zn) → ninhydrin → PD; and IND-Zn → ninhydrin → Oil Red O (ORO) → PD. Samples were examined after the addition of each chemical treatment. DNA was collected with cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. DNA profiles were obtained with varying degrees of success, depending on the number and type of treatments used for latent fingerprint development. The treatments that were found to be the least harmful to downstream DNA analysis were IND-Zn and IND-Zn/laser, and the most detrimental treatments were DFO, DFO/laser, and PD. In general, as the number of treatments increase, the opportunities for DNA loss or damage also increase, and it is preferable to use fewer treatments when developing latent fingerprints prior to downstream DNA processing.     

Development of microwave-assisted extraction procedure for organic impurity profiling of seized 3,4-methylenedioxymethamphetamine (MDMA)

Abstract: Organic impurity profiling of seized 3,4‐methylenedioxymethamphetamine (MDMA) tablets aims to link tablets to common production sources. Conventionally, organic impurities are extracted from tablets using a liquid–liquid extraction (LLE) procedure prior to analysis by gas chromatography–mass spectrometry (GC‐MS). In this research, the development of an alternative microwave‐assisted extraction/headspace solid‐phase microextraction (MAE/HS‐SPME) procedure is described. The optimal procedure used phosphate buffer (1 M, pH 8), with an HS‐SPME extraction temperature of 70°C for 40 min, using a divinylbenzene/Carboxen?/polydimethylsiloxane (DVB/CAR/PDMS) fiber. Impurities were extracted from seized MDMA exhibits using the MAE/HS‐SPME procedure, as well as HS‐SPME alone, and a conventional LLE procedure. The HS‐SPME procedure was deemed to be the most practical because of the affordability and need for less analyst involvement. Although the LLE was limited in the number of impurities extracted, the procedure is still useful for the extraction of less volatile impurities that are not extracted by HS‐SPME.     

Teaching Obama: history,critical race theory and social work education

ABSTRACT

Barack Obama's first autobiography, Dreams from My Father (1995), explores themes of race and identity up to the late 1980s in the life of the first African American president. The book emphasizes Obama's personal struggle as the son of an interracial couple, and the social and environmental context that shaped his growth and transformation. Using the tools of critical race theory, Freeman illustrates how Obama's autobiography can be used in the classroom to explore an individual's developing racial consciousness in the 1970s and 1980s, and as a prism through which students can understand what it means to live in the post-civil-rights-movement era. Obama's life history illuminates how the ideas and meanings of racial progress in the United States are contested and struggled over on a daily basis at both the micro and macro level.     

Prejudice against Gypsies among Spanish adolescents

This article examines the attitudes of Spanish adolescents towards Gypsies, the most discriminated group in Spain, by looking at two distinct attitudinal components: the first, the cognitive component, was studied by measuring a willingness to extend twelve rights to Gypsies; the second, the affective component, by assessing a liking for this group. The research demonstrated that the adolescents' willingness to extend rights to Gypsies was greater than their liking for them. Furthermore, the adolescents were more willing to extend social rights than political ones. Older adolescents, females, those with higher self-esteem, greater political experience, a more resolute endorsement of democratic norms and a stronger identification with a group of friends presented more positive attitudes towards Gypsies. On the other hand, adolescents who were more supportive of violent groups, more strongly identified with the Catholic Church, other religious groups or a soccer team showed more negative attitudes towards Gypsies.     

Racial and Ethnic Differences in the Likelihood of Marriage: The Effect of Incarceration

Researchers have highlighted the importance of marriage when studying variation in deviance over the life course, but few studies have examined the effect that incarceration has on marriage or have considered variation by race and ethnicity. Using data from the National Longitudinal Survey of Youth (NLSY), this study contrasts the effect of incarceration on the likelihood of marriage for White, Black, and Hispanic males. Incarceration reduced the chances of marriage for all men, but had a significantly stronger effect on the marital outcomes for Whites. Although Whites were most likely to be married overall, incarceration was associated with a 59 percent decline in the odds of marriage for Whites, and the odds of marriage decreased 30 percent for Blacks and 41 percent for Hispanics. The association was maintained even after controlling for time‐varying life‐course events and static individual‐level factors. This research has important implications for the study of the incarceration and the consequences it can have for spouses, families, and communities.     

The Influence of Places on Police Decision Pathways: From Call for Service to Arrest

Research on factors that influence police discretion usually focuses on individual or situational characteristics (e.g., an officer or citizen's age, race or gender, or the seriousness of the incident). In contrast, this study examines whether characteristics of places influence police decisions to “upgrade” or “downgrade” their response to incidents. Earlier research is expanded in three ways: first, rather than examining an isolated decision within the series of decisions that make up an incident, a series of chronological decisions within a “decision‐making pathway” is derived and analyzed. Second, multiple categories of racial and ethnic composition of places and their influence on police decision‐making pathways are examined. Third, decision pathways of a variety of incidents at small geographic places are compared across an entire jurisdiction. Findings indicate that, even when controlling for the level of violence, places with a greater proportion of Black or wealthy residents significantly influence officers' decisions to downgrade crime classifications and actions taken on incidents reported to the police.     

The questionable advantage of defense counsel in juvenile court

This article examines the issue of legal representation in serious juvenile delinquency matters in three diverse juvenile courts. The prevalence of legal counsel varied among felony referrals. Out-of-home placement was more likely to occur if a youth had an attorney, even when other relevant legal and individual factors were the same. Within each court, the results showed more likely of placement corresponding to seriousness of the case. Although this escalation was evident among cases with attorneys and those without, placement was more apt to occur when there was legal counsel. Given these findings, we offer recommendations for issues that should be considered and possible policy actions.     

Recovery of DNA and fingerprints from touched documents

This study investigated the various factors affecting DNA profiling from DNA recovered from fingerprints deposited on paper before and after fingerprint enhancement treatments. The DNeasy^® plant mini kit (QIAGEN^®) was found to improve DNA recovery from paper by over 150% compared with the QIAamp^® mini kit. A significant decrease in the amount of DNA recovered was observed following treatment with DFO and/or Ninhydrin. This decrease in yield did not have a comparably significant effect on the quality of the SGM Plus™ profiles. Furthermore, this study found that whilst certain paper types, such as newspaper, magazine and filter paper allowed for the good recovery of DNA, common office paper and white card, strongly interfered with the recovery of DNA resulting in poor quality profiles.     

MiniSTR技术的研究进展

短串联重复序列(STR)是法医DNA鉴定中最常用和最重要的遗传标记,但是对于降解和微量的DNA样品,经常得不到完整的DNA分型甚至分型失败。MiniSTR技术通过设计更靠近重复序列的引物,得到更短一些的STR基因座,提高了降解和微量检材的DNA分型成功率。本文综述了miniSTR技术的研究进展,以服务于法医学实践。