Motivations for Social Media Use: Associations with Social Media Engagement and Body Satisfaction and Well-Being among Adolescents

Journal of Youth and Adolescence - Adolescents are spending considerable time on social media, yet it is unclear whether motivations for social media use drive different forms of social media...     

Parent–Adolescent Conflict across Adolescence: Trajectories of Informant Discrepancies and Associations with Personality Types

Journal of Youth and Adolescence - Parent–adolescent conflict can be intense, yet parents and adolescents do not always agree on the intensity of conflict. Conflict intensity tends to change...     

Sample Mining and Data Mining: Combined Real-Time and Retrospective Approaches for the Identification of Emerging Novel Psychoactive Substances

Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH^® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone.     

Volatile Organic Compounds,Spectral Characterization and Morphology of Ammonium Nitrate Fuel Oil (ANFO) Samples

Ammonium nitrate fuel oil is an explosive mixture found in most antipersonnel landmines (APL) buried throughout the Colombian territory. During more than 50 years of internal conflict, the Colombian government has found that trained dogs are the most effective method to detect APL. However, the olfactive signature in ANFO is unknown and also if there are differences in detection related to the explosive manufacturing origin. Therefore, this work begins with the analytical validation of the method used to determine ammonia, in its derivatized form as carbamate, released by home-made ANFO using HS-SPME-GC-FID. Once validated, the method was used to identify ammonia and other organic volatile compounds present in ANFO, under laboratory and simulated field conditions. The validation process includes the evaluation of the optimum conditions for the derivation and extraction of butylcarbamate, the determination of the working ranges with linear response in FID, the limits of detection and quantification, the sensitivity, and the precision. The results of the validation established linearity and sensitivity in a concentration between 20 and 120 mg/L, as well as low limits of detection and quantification of 6.4 and 21.4 mg/L, respectively. Also, an intermediate precision of 11% for butylcarbamate with a repeatability of 8%. The validated method showed in real samples of home-made ANFO besides ammonia, the presence of low molecular methylamines, and also exhibited differences in volatile compositions according to the origin. The objective of this work is to offer a reliable analytical methodology for the extraction and analysis of volatile compounds from ANFO.     

Students’ Personal Belief in a Just World,Well-Being,and Academic Cheating: A Cross-National Study

Social Justice Research - A cross-national study with university students from Germany (n?=?1135) and Turkey (n?=?634) tested whether personal belief in a just world (PBJW)...     

Adolescents’ Self-Perception of Morality,Competence, and Sociability and their Interplay with Quality of Family,Friend, and School Relationships: A Three-Wave Longitudinal Study

Morality, competence, and sociability have been conceptualized as fundamental dimensions on which individuals ground their evaluation of themselves and of other people and groups. In this study, we examined the interplay between self-perceived morality, competence, and sociability and relationship quality within the core social contexts with which adolescents have extensive daily interactions (family, friends, and school). Participants were 916 (51.4% girls; M_age?=?15.64 years) adolescents involved in a three-wave longitudinal study with annual assessments. The results of cross-lagged analyses indicated that (a) self-perceived morality was more important than self-perceived competence and sociability in strengthening family, friend, and school relationships; and (b) high-quality friendships led to increasing levels of self-perceived morality over time. Overall, this evidence advances our theoretical understanding of the primacy of morality from a self-perspective approach and highlights the developmental importance of friends.     

Dual-Credit Courses and the Road to College: Experimental Evidence from Tennessee

Dual-credit courses expose high school students to college-level content and provide the opportunity to earn college credits, in part to smooth the transition to college. With the Tennessee Department of Education, we conduct the first randomized controlled trial of the effects of dual-credit math coursework on a range of high school and college outcomes. We find that the dual-credit advanced algebra course alters students’ subsequent high school math course-taking, reducing enrollment in remedial math and boosting enrollment in precalculus and Advanced Placement math courses. We fail to detect an effect of the dual-credit math course on overall rates of college enrollment. However, the course induces some students to choose four-year universities instead of two-year colleges, particularly for those in the middle of the math achievement distribution and those first exposed to the opportunity to take the course in eleventh rather than twelfth grade. We see limited evidence of improvements in early math performance during college.