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921.
Adam Lanzarotta Ph.D. Mark Witkowski Ph.D. JaCinta Batson M.S. 《Journal of forensic sciences》2020,65(2):421-427
This study describes the performance of handheld Raman devices for detecting one hundred opioids and related substances including fentanyl and several analogs. Using a single “parent” device, signatures (spectra) with excellent signal-to-noise ratios were generated using <5 mg of most compounds. The signatures were added to a method (library), which was electronically transferred to three “daughter” devices. The devices were able to discriminate different salt forms and isomers. On average, the daughter devices yielded a true-positive rate of 97.3% for generating an alarm for opioids and were 93.3% effective for correctly identifying the opioid. The devices yielded true-negative, false-positive and false-negative rates of 100%, 0%, and 2.7%, respectively, where false negatives were due to weak signal and fluorescence. These data demonstrate that the parent-daughter electronic transfer method was successful and effective, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. 相似文献
922.
Keith L. Monson Ph.D. Kelsey M. Kyllonen M.A. Jeffrey L. Leggitt M.S. Kelli E. Edmiston M.S. Calvin R. Justus Ph.D. Mark F. Kavlick Ph.D. Maria Phillip B.S.Ch.E. Maria A. Roberts M.S. Candie W. Shegogue M.S. Gabriel D. Watts B.A. 《Journal of forensic sciences》2020,65(6):1894-1907
In addition to having blast mitigation properties, aqueous foam concentrate AFC-380 blast suppression foam is designed to capture aerosolized chemical, biological, and radioactive particles during render-safe procedures of explosive devices. Exposure to aqueous environments and surfactants may negatively affect forensic evidence found at the scene, but the effects of AFC-380 foam and aqueous gel on the preservation and subsequent analysis of forensic evidence have not previously been investigated. Sebaceous finger and palm prints and DNA samples on paper, cardboard, tape, and various metal and plastic items, along with hairs, carpet and yarn fibers, and inks and documents, were exposed to AFC-380 foam. Similar mock evidence was also exposed to a superabsorbent gel of the type found in aqueous gel blocks used for shrapnel containment. Exposure to foam or aqueous gel was associated with a dilution effect for recovered DNA samples, but quality of the samples was not substantially affected. In contrast, exposure to AFC-380 foam or gel was detrimental to development of latent finger and palm prints on any substrate. Neither the hair nor the fiber samples were affected by exposure to either the foam or gel. Indented writing on the document samples was detrimentally affected by foam or gel exposure, but not inks and toners. The results from this study indicate that most types of forensic evidence recovered after being exposed to aqueous gel or blast suppression foam can be reliably analyzed, but latent finger and palm prints may be adversely affected. 相似文献
923.
This study examines hypotheses regarding patterns of developmental change in street code commitment from childhood through emerging adulthood. It tests whether street code commitment demonstrates developmental stability or if it fluctuates in response to evolving socially demoralizing conditions. Latent growth curve and parallel process models are applied to longitudinal data from an African American sample. Confirmatory factor analysis tests the degree to which neighborhood violence, peer processes, and family hostilities combine to form a latent construct of socially demoralizing environments. Analysis also tests measurement invariance across the study assessment periods. Street code commitment demonstrates a non-linear growth pattern across time. Commitment increases in childhood, peaks in late adolescence, and declines in emerging adulthood. Exposure to demoralizing social environments demonstrates a similar pattern of change characterized by a peak in adolescence followed by a gradual decline. Harsh childhood social environments affect the initial levels but not the growth of the street code. Street code commitment fluctuates in response to contemporaneous environmental conditions. The street code is malleable from childhood through emerging adulthood. Commitment to the street code is not a stable product of socialization or early childhood social environmental exposures. The degree to which individuals embrace the code is largely a function of their current social environment. 相似文献
924.
Kruis Nathan E. Wentling Richard L. Heirigs Mark H. Ishoy Glen A. 《American Journal of Criminal Justice》2020,45(1):25-47
American Journal of Criminal Justice - Recent incidents of mass shootings in schools have raised questions about the availability of “military-style” firearms and need for campus carry... 相似文献
925.
The landmark U.S. Budget and Accounting Act of 1921 (BAA) instituted a series of administrative reforms that proponents claimed would improve budgetary control, stability, and coherence. We maintain that the compatibility of governance structures between agency and system levels is critical for understanding why these administrative centralization efforts were successful in achieving these aims for some federal agencies but not others. The BAA reforms impact on budgetary outcomes is evaluated using panel data on major U.S. federal agencies between 1894 and 1940. Applying semiparametric heterogeneous treatment estimation techniques, we find compelling support that administrative centralization of the federal budgetary process enhanced budget stability and coherence for executive departments while resulting in a lower caliber of budgetary performance for independent agencies. These findings imply that system‐level administrative centralization efforts may be effective only when public agencies are structurally amenable to such reforms. 相似文献
926.
Middle class is a social construct and a moniker so central to the identity politics of the United States that it has become a persistent part of the rhetoric of both major political parties. This article seeks to understand how the way in which people categorize themselves in social class matches the observable characteristics that might be used to objectively classify them into such groups. This article examines survey data from a national poll and finds that a majority of the respondents consider themselves members of the middle class. While those in the lowest and highest income categories are less likely to categorize themselves as middle class (controlling for other factors), many in these groups also consider themselves middle class. 相似文献
927.
928.
Mark Rhinard 《政策研究评论》2009,26(4):439-455
As crises grow more transnational in origin and effect, managing them effectively will require international cooperation. This article explores the dilemmas inherent to producing common crisis management capacities across national governments. Drawing on the literature related to "international public goods," the article builds an approach for understanding these dilemmas through the lens of collective action and the perverse incentives associated therein. The article applies this approach to cooperation in Europe on an issue that typifies the transnational crisis—the spread of communicable disease—and highlights obstacles to European Union ambitions to build a robust system for disease surveillance and control. Having isolated the obstacles, the article then identifies solutions to facilitate cooperation toward more effectively producing the good in question. 相似文献
929.
Melissa A. Lippold Mark T. Greenberg Linda M. Collins 《Journal of youth and adolescence》2013,42(11):1732-1744
Most studies isolate the effects of one knowledge-related behavior on youth outcomes. This study explores the relationship between subgroups of mother–youth dyads that use specific combinations of parental knowledge-related behaviors and youth risky behavior. Using a sample of 796 rural 6th graders (53 % female), we assessed mother and youth reports of maternal knowledge, active parent monitoring efforts, youth disclosure, parental supervision, and the amount of parent–youth communication to identify five knowledge latent classes: High-Monitors, Maternal Over-Estimators, Low-Monitors, Communication-Focused, and Supervision-Focused. Delinquency, antisocial peers, and substance use were associated with increased odds of membership in the Supervision-Focused class, relative to the High Monitors. Membership in the Low Monitors and Maternal Over-Estimators classes was associated with unhealthy attitudes towards substances and for Low Monitors, substance use. The discussion focuses on the value of using a person-oriented approach to understand parental knowledge and risky behavior during early adolescence and intervention implications. 相似文献
930.
Molly Copeland Jacob C. Fisher James Moody Mark E. Feinberg 《Journal of youth and adolescence》2018,47(8):1755-1770
Social isolation is broadly associated with poor mental health and risky behaviors in adolescence, a time when peers are critical for healthy development. However, expectations for isolates’ substance use remain unclear. Isolation in adolescence may signal deviant attitudes or spur self-medication, resulting in higher substance use. Conversely, isolates may lack access to substances, leading to lower use. Although treated as a homogeneous social condition for teens in much research, isolation represents a multifaceted experience with structurally distinct network components that present different risks for substance use. This study decomposes isolation into conceptually distinct dimensions that are then interacted to create a systematic typology of isolation subtypes representing different positions in the social space of the school. Each isolated position’s association with cigarette, alcohol, and marijuana use is tested among 9th grade students (n?=?10,310, 59% female, 83% white) using cross-sectional data from the PROSPER study. Different dimensions of isolation relate to substance use in distinct ways: unliked isolation is associated with lower alcohol use, whereas disengagement and outside orientation are linked to higher use of all three substances. Specifically, disengagement presents risks for cigarette and marijuana use among boys, and outside orientation is associated with cigarette use for girls. Overall, the adolescents disengaged from their school network who also identify close friends outside their grade are at greatest risk for substance use. This study indicates the importance of considering the distinct social positions of isolation to understand risks for both substance use and social isolation in adolescence. 相似文献