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221.
Ju Yeon Jung M.S. Ga Hee Ryu B.S. Da-Hye Kim B.S. Joo-Young Kim Ph.D. In Kwan Hwang Ph.D. Pil-Won Kang Ph.D. Byung Won Chun Ph.D. Seong Yeon Yoo Ph.D. 《Journal of forensic sciences》2020,65(1):209-213
When using non-FTA cards in commercial multiplex STR kits for direct PCR, pretreatment steps with specific buffers are recommended. Here, we designed a rapid direct PCR method utilizing a non-FTA card, Oral Cell Sampling Kit, by omitting the pretreatment step involving Prep-n-Go™ Buffer, and it showed compatibility with the GlobalFiler™ Express PCR Amplification Kit, GlobalFiler™ PCR Amplification Kit, and PowerPlex® Fusion system. To optimize the PCR conditions, we tested the method with different final PCR volumes and cycles. Finally, we conducted a performance test using 50 Korean buccal samples and confirmed the high performance of the method, detecting more than 90% of the samples with full profiles when using GlobalFiler™ PCR Amplification Kit and PowerPlex® Fusion system at 29 cycles in a 10 μL final PCR volume. Thus, we report a simple direct PCR set-up to analyze reference samples collected using a non-FTA card manufactured in Korea. 相似文献
222.
Minji Lee M.S. Ju Yeon Jung M.S. Sungsoo Choi M.S. Ilung Seol Ph.D. Seohyun Moon Ph.D. In Kwan Hwang Ph.D. 《Journal of forensic sciences》2020,65(6):2117-2120
Lophophora is a member of the Cactaceae family, which contains two species: Lophophora williamsii and L. diffusa. Lophophora williamsii is an illegal plant containing mescaline, a hallucinogenic alkaloid. In this study, a novel method based on a single nucleotide polymorphism (SNP) assay was developed for identifying L. williamsii; this assay reliably detects SNPs within chloroplast DNA (rbcL, matK, and trnL-trnF IGS) and was validated for identifying Lophophora and L. williamsii simultaneously. The chloroplast DNA sequences from four L. williamsii and three L. diffusa plants were obtained and compared using DNA sequence data from approximately 300 other Cactaceae species available in GenBank. From this sequence data, a total of seven SNPs were determined to be suitable for identifying L. williamsii. A multiplex assay was constructed using the ABI PRISM® SNaPshot™ Multiplex Kit (Applied Biosystems, Forster City, CA) to analyze species-specific SNPs. Using this multiplex assay, we clearly distinguished the Lophophora among 19 species in the Cactaceae family. Additionally, L. williamsii was distinguished from L. diffusa. These results suggest that the newly developed assay may help resolve crimes related to illegal distribution and use. This multiplex assay will be useful for the genetic identification of L. williamsii and can complement conventional methods of detecting mescaline. 相似文献
223.
Virginie Redouté Minzière M.Sc. Denis Werner M.Sc. Daniela Schneider M.Sc. Manuela Manganelli M.S. Balthasar Jung Ph.D. Céline Weyermann Ph.D. Anne-Laure Gassner Ph.D. 《Journal of forensic sciences》2020,65(4):1102-1113
Gunshot residue (GSR) analysis and their interpretation provide crucial information on a criminal investigation involving the use of firearms. To date, several approaches have been proposed for the implementation of a combined sampling and analysis of inorganic (IGSR) and organic GSR (OGSR). However, it is not clear at this stage if concurrent analyses of both types of residue might be detrimental to the analysis of IGSR currently applied in forensic laboratories. Thus, this work aims to compare and evaluate three different protocols for the combined collection and analysis of IGSR and OGSR. These methods, respectively, involve the use of a modified stub (with two halves, one for the detection of IGSR and the other for the analysis of OGSR); the sequential recovery of GSR with two stubs mounted with different adhesives (double-sided carbon tape and Tesa® TACK) and the sequential analysis of IGSR and OGSR from a single carbon stub following carbon deposition. The detection of IGSR was carried out using SEM-EDX, while OGSR analysis was performed using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Obtained results for experiments performed using Geco Sinoxid® ammunition indicated that sequential analysis was the most suitable protocol for the combined collection and analysis of both IGSR and OGSR. A higher number of inorganic (characteristic and consistent) particles and higher concentrations of ethylcentralite, N-nitrosodiphenylamine, diphenylamine, and nitroglycerin were recovered with this method. 相似文献
224.
Jolien Trekels Kathrin Karsay Steven Eggermont Laura Vandenbosch 《Journal of youth and adolescence》2018,47(7):1440-1455
Although media exposure has been related to cognitive preoccupation with appearance, research rarely investigated adolescents’ behavioral self-sexualization. To address this gap, the present study among 12- to 16-year-olds (N?=?1527; 50.2% girls) in Austria, Belgium, Spain, and South-Korea (1) investigates whether different types of media use relate to self-sexualization, (2) explores the explanatory value of rewarded appearance ideals, and (3) considers culture and gender as moderating factors. Despite cultural variation, a general trend of increasing self-sexualization with social media use and magazine reading appeared across the countries. Moreover, women’s magazine reading and rewards were related to self-sexualization among all the girls across the countries, which suggests that girls may be more vulnerable to the examined effects. Overall, this study provides a better understanding of the unique contribution of specific media genres to youth’s self-sexualization and points at the importance of social media use in girls’ and boys’ engagement in sexualizing appearance behaviors across four countries. 相似文献
225.
Disordered eating is highly prevalent during adolescence and has a detrimental effect on further development. Effective prevention programs are needed to prevent unhealthy developmental trajectories. This study evaluated the efficacy of the POPS-program (POtsdam Prevention at Schools), a universal school-based eating disorder prevention program for adolescents. In a cluster-randomized design, we compared the intervention group receiving the prevention program to a waiting control group. Outcomes included indicators of disordered eating and relevant risk factors for eating disorders (body dissatisfaction, internalization of the thin ideal, perceived media pressure, perfectionism, emotional element of exercise, social comparison, and perceived teasing). Questionnaires were administered at the start of the intervention, 3 and 12 months post intervention. At baseline, 1112 adolescents aged 10 to 16 years participated (49% girls; 51% intervention group). Intention-to-treat analyses with the complete data set and per-protocol analyses as a completer analysis were performed. The intervention group showed a more favorable course compared to the control group regarding all observed risk factors for eating disorders except for perceived teasing. Effect sizes were small but comparable to other primary prevention programs. At 1-year follow-up, a small but significant effect on disordered eating was observed. Results of the per-protocol analyses were mostly confirmed by the intention-to-treat analyses. Results were promising for both genders although girls benefited more regarding disordered eating and internalization of the thin ideal. Further studies are warranted examining successful program elements and whether gender-specific programs are needed. 相似文献
226.
227.
Adolescent romantic relationships have the potential to affect psychological functioning well into adulthood. This study assessed adolescent romantic relationship qualities as long-term predictors of psychological functioning utilizing a longitudinal multi-method, multi-informant study of 80 participants (59% female; 54% Caucasian, 35% African American, 11% mixed or other race) assessed at age 17 along with their romantic partners and at ages 25–27. Controlling for gender, family income, and baseline mental health, partner-reported hostile conflict at age 17 predicted relative increases in internalizing behaviors from age 17 to 27. In contrast, observed teen support with their partner during a help-seeking task at age 17 predicted relative decreases in externalizing behaviors over time. The results are interpreted as suggesting qualities that may help determine whether adolescent romances have positive vs. negative long-term psychological health implications. 相似文献
228.
Lyda Lannegrand-Willems Basilie Chevrier Cyrille Perchec Alexia Carrizales 《Journal of youth and adolescence》2018,47(4):731-748
Adolescence and emerging adulthood are periods in life when individuals both question and define their place in society and form their identity. Meanwhile, active youth civic engagement represents a challenge for each democracy. The purpose of this study was to analyze the different forms of civic engagement among late adolescents and emerging adults and how they are related to personal identity and social identity, while adopting an integrative perspective through the lens of a person-oriented approach. The participants were 1217 (62.3% female) 16–24 year-old French students (M age ?=?19.17; SD age ?=?1.83). First, derived from cluster analyses, the findings emphasized diversity in civic engagement, from strong civic participation (in different formal and informal ways) to various forms of passivity. Diversity was also highlighted for personal identity and social identity profiles. Second, a Configural Frequency Analysis revealed a typical pattern associating passivity in civic engagement, personal carefree diffusion and rejection of social identity. Overall, these findings highlight an absence of general youth disaffection and provide a meaningful specific pattern for the understanding of passivity in political and civic matters in late adolescence and emerging adulthood. 相似文献
229.
Nicole A. Anderson Amy M. Bohnert Amy Governale 《Journal of youth and adolescence》2018,47(8):1697-1711
Research examining factors that predict youth’s involvement in organized activities is very limited, despite associations with positive outcomes. Using data from 1043 youth (49% female; 46.4% Hispanic, 35.4% African American, 14.0% Caucasian, and 4.2% other) from the Project on Human Development in Chicago Neighborhoods, this study examined how characteristics of parents (supervision, warmth) and neighborhoods (perceived neighborhood safety and collective efficacy) predict patterns of adolescents’ involvement in organized activities concurrently (i.e., intensity) and longitudinally (i.e., type and breadth). Parental supervision predicted adolescents’ participation in organized activities across multiple waves. Neighborhood violence was positively associated with concurrent participation in organized activities after controlling for socioeconomic status (SES), whereas higher neighborhood collective efficacy predicted greater breadth in organized activity participation across time. These findings have important implications regarding how to attract and sustain organized activity participation for low-income, urban youth. 相似文献
230.
Sleep problems and emotion dysregulation are associated with depressive symptoms and alcohol use but little research has examined the long-term associations and the direction of effects between these factors. We examined these relationships with 1132 undergraduates (70.5% female) over 5 years. Sleep problems and emotion dysregulation, sleep problems and depressive symptoms, and emotion dysregulation and depressive symptoms were all related bidirectionally. Tests of indirect effects indicated that sleep problems predicted depressive symptoms over time (and vice versa) via emotion dysregulation and emotion dysregulation predicted depressive symptoms over time (and vice versa) via sleep problems. The results highlight the need to assess direction of effects, given that many factors that are typically seen as “predictors” also can be framed as “outcomes”. 相似文献