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111.
Abstract:  Laser desorption mass spectrometry (LDMS) is emerging as a technique for questioned document examination. Its use is limited to detecting ink dyes that are neutral or singly charged. Several inks contain dyes that are multiply charged and LDMS cannot be employed for their identification. We have successfully detected >20 polyionic dyes that can be used in the manufacture of inks using matrix-assisted laser desorption/ionization (MALDI) MS, directly from paper, with the matrix, 2-(4-hydroxyphenylazo)benzoic acid (HABA), and the additive, diammonium hydrogen citrate (DAHC). For example, Acid Violet 49, a charged dye containing one positively-charged site and two negatively charged sulfonate groups, cannot be detected by LDMS, but forms intact, singly charged ions in the MALDI MS experiment. The method described is also useful for identifying multiply charged dye mixtures that are used in modern pen inks.  相似文献   
112.
Abstract: Anyone with a computer, scanner, and color printer has the capability for creating documents such as identification cards, passports, and counterfeit currency. Laser desorption mass spectrometry (LDMS) has been demonstrated as a powerful tool for colorant analysis. Inkjet printers are now moving largely toward the use of pigments as colorants; their insolubility makes analysis by simpler methods such as thin‐layer chromatography no longer an option. Recent developments in pigmented inkjet printer inks, such as gloss optimizers that coat pigment particles, may prohibit colorant analysis by LDMS. We demonstrate here that pigments used in inks from two Epson printers can be detected and analyzed by LDMS. Also, LDMS spectra of various colors created using a 4‐cartridge (cyan/magenta/yellow/black, CMYK) inkset are evaluated, to begin to develop an approach for unraveling LDMS data from real samples, to determine the number of inks used by a printer, and the chemical composition of the colorants.  相似文献   
113.
Abstract:  Human scent evidence is utilized as an investigative tool through canine scent discriminations based on the premise that human scent is an individualizing characteristic. This study describes the development of what is effectively a human scent barcode consisting of the relative ratios of an individual's "primary odor" compounds utilized to determine a reproducible and individualizing profile which can be stored in a searchable database for a proof of concept of human scent as a biometric measure. Triplicate hand odor samples were evaluated from 10 subjects utilizing solid phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and compared via Spearman Rank Correlations. Narrowing the compounds considered for each subject to only those common in all three samples, or a subject's "primary odor constituents," produced a greater degree of both individualization and discrimination; at both correlation thresholds of 0.9 and 0.8, the individuals were correctly discriminated and identified in 99.54% of the cases.  相似文献   
114.
Reviewing the literature on police-induced confessions, we identified suspect characteristics and interrogation tactics that influence confessions and their effects on juries. We concluded with a call for the mandatory electronic recording of interrogations and a consideration of other possible reforms. The preceding commentaries make important substantive points that can lead us forward—on the effects of videotaping of interrogations on case dispositions; on the study of non-custodial methods, such as the controversial Mr. Big technique; and on an analysis of why confessions, once withdrawn, elicit such intractable responses compared to statements given by child and adult victims. Toward these ends, we hope that this issue provides a platform for future research aimed at improving the diagnostic value of confession evidence.  相似文献   
115.
Mental health courts (MHCs) are rapidly expanding as a form of diversion from jails and prisons for persons with mental illness charged with crimes. Although intended to be voluntary, little is known about this aspect of the courts. We examined perceptions of voluntariness, and levels of knowingness and legal competence among 200 newly enrolled clients of MHCs at two courts. Although most clients claimed to have chosen to enroll, at the same time, most claimed not to have been told the court was voluntary or told of the requirements prior to entering. The majority knew the “basics” of the courts, but fewer knew more nuanced information. A minority also were found to have impairments in legal competence. Implications are discussed.  相似文献   
116.
Most footwear marks made in blood on a surface such as fabric tend to be enhanced in situ rather than physically recovered using a lifting technique prior to enhancement. This work reports on the use of an alginate material to recover the impressed footwear marks made in blood and deposited on a range of fabric types and colours. The lifted marks were then enhanced using acid black 1 and leuco crystal violet with excellent results.This presents a new method for the lifting and recovery of blood impressions in situ from crime scene followed by subsequent mark enhancement of the lifted impression.  相似文献   
117.

Objectives

This study proposes a theoretical framework for understanding two empirical findings from gang research: (1) gangs are generally racially homogenous, even in heterogeneous environments, and (2) gang violence tends to be intra-racial. We draw from the extensive literature on street gangs as well as from research on group formation and status-enhancing behavior to develop a theoretical model of gang formation.

Methods

Using game theory, we model the simultaneous decisions of individuals to commit status-enhancing acts of violence and to seek protection by joining a gang. We then conduct computer simulations to examine the resulting patterns of violence and gang composition.

Results

We demonstrate that as long as some social distance exists between racial groups in a community, gang violence will be intra-racial and gangs will be homogenous. We find that our results are robust to a number of simple variations of the model and allow us to generate several hypotheses about the nature of gang formation and patterns of violence.

Conclusions

When violence is motivated by socially constructed rewards, socially closer targets are likely to yield greater rewards. In such a system, individuals must reduce their likelihood of victimization by entering a social contract of non-violence (i.e. gang membership) with individuals who might view them as status-enhancing targets (i.e. socially close individuals). The result is that gangs are made up of socially close individuals interested in attacking other socially close individuals. Therefore, gangs tend to be racially homogenous and violence is overwhelmingly intra-racial.
  相似文献   
118.
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.  相似文献   
119.
Abstract

Four decades ago the Indian states of Gujarat and Tamil Nadu had identical scores on the human development index. Both states have since experienced similar rates of economic growth and Gujarat has received more foreign investment, but Tamil Nadu has witnessed much stronger advances in human development. What explains this divergence? Through comparative historical, statistical and public policy analysis and interviews, we conclude that the implementation of government policies as a manifestation of political ideology and the quality of public administration have played a defining role in explaining Gujarat’s more lopsided and Tamil Nadu’s more balanced human development trajectories. Our findings suggest that a more egalitarian ideology and higher quality of public administration have been crucial to Tamil Nadu’s success in simultaneously improving human and economic development.  相似文献   
120.
Courts have increasingly looked to the concept of “transformative use” to determine whether the use of a copyrighted work is protected under the fair use doctrine. Judge Pierre Leval's definition of transformative use, adopted by the Supreme Court of the United States in its 1994 opinion in Campbell v. Acuff-Rose Music, Inc., requires that a transformative use must (1) be socially beneficial, (2) be used in a different way or purpose from the original, and (3) add value to the original by using it as raw material to create something new. This article examines the fair use analysis undertaken by the United States Court of Appeals for the Ninth Circuit in two recent cases involving visual search engines and concludes that the court's test of transformative use ignored the language and the meaning of the Campbell definition and instead equated a finding of a different purpose with a finding of a transformative use. This departure from traditional transformative use analysis, if generally adopted by the court, would represent a significant and potentially troubling doctrinal shift in fair use analysis.  相似文献   
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