Social media and online communities expose youth to political conversation, but also to incivility and conflict.

The internet and social media now mean that young people are more able to engage with, and participate in the political process. But does this engagement also expose young people to a greater risk of online abuse? In new research Ellen Middaugh investigates the exposure to conflict and incivility of young people who engage politically online. She finds that exposure to online conflict is common, and is associated with participatory media, and that many youth also see no problem with escalating language and personal insults in online political conversations

New Media and Youth Political Action

To rigorously consider the impact of new media on the political and civic behavior of young people, The MacArthur Research Network on Youth and Participatory Politics (YPP) developed and fielded one of the first large-scale, nationally representative studies of new media and politics among young people. The two principal researchers for the survey component of the YPP, Cathy J. Cohen of the University of Chicago and Joseph Kahne of Mills College, oversaw a research team that surveyed nearly 3,000 respondents between the ages of 15 and 25 years of age. Unlike any prior study of youth and new media, this study included large numbers of black, Latino, and Asian American respondents, which allows for unique and powerful statistical comparisons across race with a focus on young people.Until now there has been limited opportunity and data available to comprehensively explore the relationship between new media and the politics of young people. One of the few entities to engage in this type of rigorous analysis has been the Pew Internet and American Life Project. The YPP study expands on this field-leading work by including an extensive battery of items addressing participatory politics and adequate numbers of participants from different racial and ethnic groups, thus allowing for analysis of how different groups of young people were engaged with new media in the political realm.The YPP study findings suggest that fundamental changes in political expectations and practices may be occurring -- especially for youth. The analysis of the data collected reveals that youth are taking advantage of an expanded set of participatory practices in the political realm in ways that amplify their voice and sometimes their influence, thus increasing the ways young people participate in political life. The YPP researchers label this expanded set of opportunities and actions participatory politics

Why Do Alumni Return to the School of Law to Teach?

The question is easily answered by alumni adjuncts devoted to their alma mater and committed to sharing their expertise with the next generation of lawyers

Teens, Video Games, and Civics

Analyzes survey findings on trends in teenagers' video gaming, the social context, the role of parents and monitoring, and the link between specific gaming experiences and civic activities. Explores gaming's potential as civic learning opportunities

Association of Secondhand Smoke Exposure with Pediatric Invasive Bacterial Disease and Bacterial Carriage: A Systematic Review and Meta-analysis

Background: A number of epidemiologic studies have observed an association between secondhand smoke (SHS) exposure and pediatric invasive bacterial disease (IBD) but the evidence has not been systematically reviewed. We carried out a systematic review and meta-analysis of SHS exposure and two outcomes, IBD and pharyngeal carriage of bacteria, for Neisseria meningitidis (N. meningitidis), Haemophilus influenzae type B (Hib), and Streptococcus pneumoniae (S. pneumoniae). Methods and Findings: Two independent reviewers searched Medline, EMBASE, and selected other databases, and screened articles for inclusion and exclusion criteria. We identified 30 case-control studies on SHS and IBD, and 12 crosssectional studies on SHS and bacterial carriage. Weighted summary odd ratios (ORs) were calculated for each outcome and for studies with specific design and quality characteristics. Tests for heterogeneity and publication bias were performed. Compared with those unexposed to SHS, summary OR for SHS exposure was 2.02 (95% confidence interval [CI] 1.52–2.69) for invasive meningococcal disease, 1.21 (95% CI 0.69–2.14) for invasive pneumococcal disease, and 1.22 (95% CI 0.93–1.62) for invasive Hib disease. For pharyngeal carriage, summary OR was 1.68 (95% CI, 1.19–2.36) for N. meningitidis, 1.66 (95% CI 1.33–2.07) for S. pneumoniae, and 0.96 (95% CI 0.48–1.95) for Hib. The association between SHS exposure and invasive meningococcal and Hib diseases was consistent regardless of outcome definitions, age groups, study designs, and publication year. The effect estimates were larger in studies among children younger than 6 years of age for all three IBDs, and in studies with the more rigorous laboratory-confirmed diagnosis for invasive meningococcal disease (summary OR 3.24; 95% CI 1.72–6.13). Conclusions: When considered together with evidence from direct smoking and biological mechanisms, our systematic review and meta-analysis indicates that SHS exposure may be associated with invasive meningococcal disease. The epidemiologic evidence is currently insufficient to show an association between SHS and invasive Hib disease or pneumococcal disease. Because the burden of IBD is highest in developing countries where SHS is increasing, there is a need for high-quality studies to confirm these results, and for interventions to reduce exposure of children to SHS

Spa47 is an oligomerization-activated type three secretion system (T3SS) ATPase from \u3cem\u3eShigella flexneri\u3c/em\u3e

Gram-negative pathogens often use conserved type three secretion systems (T3SS) for virulence. The Shigella type three secretion apparatus (T3SA) penetrates the host cell membrane and provides a unidirectional conduit for injection of effectors into host cells. The protein Spa47 localizes to the base of the apparatus and is speculated to be an ATPase that provides the energy for T3SA formation and secretion. Here, we developed an expression and purification protocol, producing active Spa47 and providing the first direct evidence that Spa47 is a bona fide ATPase. Additionally, size exclusion chromatography and analytical ultracentrifugation identified multiple oligomeric species of Spa47 with the largest greater than 8 fold more active for ATP hydrolysis than the monomer. An ATPase inactive Spa47 point mutant was then engineered by targeting a conserved Lysine within the predicted Walker A motif of Spa47. Interestingly, the mutant maintained a similar oligomerization pattern as active Spa47, but was unable to restore invasion phenotype when used to complement a spa47 null S. flexneri strain. Together, these results identify Spa47 as a Shigella T3SS ATPase and suggest that its activity is linked to oligomerization, perhaps as a regulatory mechanism as seen in some related pathogens. Additionally, Spa47 catalyzed ATP hydrolysis appears to be essential for host cell invasion, providing a strong platform for additional studies dissecting its role in virulence and providing an attractive target for anti-infective agents

Phenyl radical + propene: a prototypical reaction surface for aromatic-catalyzed 1,2-hydrogen-migration and subsequent resonance-stabilized radical formation

The C[subscript 9]H[subscript 11] potential energy surface (PES) was experimentally and theoretically explored because it is a relatively simple, prototypical alkylaromatic radical system. Although the C[subscript 9]H[subscript 11] PES has already been extensively studied both experimentally (under single-collision and thermal conditions) and theoretically, new insights were made in this work by taking a new experimental approach: flash photolysis combined with time-resolved molecular beam mass spectrometry (MBMS) and visible laser absorbance. The C[subscript 9]H[subscript 11] PES was experimentally accessed by photolytic generation of the phenyl radical and subsequent reaction with excess propene (C[subscript 6]H[subscript 5] + C[subscript 3]H[subscript 6]). The overall kinetics of C[subscript 6]H[subscript 5] + C[subscript 3]H[subscript 6] was measured using laser absorbance with high time-resolution from 300 to 700 K and was found to be in agreement with earlier measurements over a lower temperature range. Five major product channels of C[subscript 6]H[subscript 5] + C[subscript 3]H[subscript 6] were observed with MBMS at 600 and 700 K, four of which were expected: hydrogen (H)-abstraction (measured by the stable benzene, C[subscript 6]H[subscript 6], product), methyl radical (CH[subscript 3])-loss (styrene detected), H-loss (phenylpropene isomers detected) and radical adduct stabilization. The fifth, unexpected product observed was the benzyl radical, which was rationalized by the inclusion of a previously unreported pathway on the C[subscript 9]H[subscript 11] PES: aromatic-catalysed 1,2-H-migration and subsequent resonance stabilized radical (RSR, benzyl radical in this case) formation. The current theoretical understanding of the C[subscript 9]H[subscript 11] PES was supported (including the aromatic-catalyzed pathway) by quantitative comparisons between modelled and experimental MBMS results. At 700 K, the branching to styrene + CH[subscript 3] was 2-4 times greater than that of any other product channel, while benzyl radical + C[subscript 2]H[subscript 4] from the aromatic-catalyzed pathway accounted for ∼10% of the branching. Single-collision conditions were also simulated on the updated PES to explain why previous crossed molecular beam experiments did not see evidence of the aromatic-catalyzed pathway. This experimentally validated knowledge of the C[subscript 9]H[subscript 11] PES was added to the database of the open-source Reaction Mechanism Generator (RMG), which was then used to generalize the findings on the C[subscript 9]H[subscript 11] PES to a slightly more complicated alkylaromatic system.Think Global Education Trus

The novel mu-opioid antagonist, GSK1521498, reduces ethanol consumption in C57BL/6J mice.

RATIONALE Using the drinking-in-the-dark (DID) model, we compared the effects of a novel mu-opioid receptor antagonist, GSK1521498, with naltrexone, a licensed treatment of alcohol dependence, on ethanol consumption in mice. OBJECTIVE We test the ability of GSK1521498 to reduce alcohol consumption and compare its intrinsic efficacy to that of naltrexone by comparing the two drugs at doses matched for equivalent receptor occupancy. METHODS Thirty-six C57BL/6J mice were tested in a DID procedure. In 2-day cycles, animals experienced one baseline, injection-free session, and one test session when they received two injections, one of test drug and one placebo. All animals received GSK1521498 (0, 0.1, 1 and 3 mg/kg, i.p., 30 min pre-treatment) and naltrexone (0, 0.1, 1 and 3 mg/kg, s.c. 10 min pre-treatment) in a cross-over design. Receptor occupancies following the same doses were determined ex vivo in separate groups by autoradiography, using [3H]DAMGO. Binding in the region of interest was measured integrally by computer-assisted microdensitometry and corrected for non-specific binding. RESULTS Both GSK1521498 and naltrexone dose-dependently decreased ethanol consumption. When drug doses were matched for 70-75 % receptor occupancy, GSK1521498 3 mg/kg, i.p., caused a 2.5-fold greater reduction in alcohol consumption than naltrexone 0.1 mg/kg, s.c. Both GSK1521498 and naltrexone significantly reduced sucrose consumption at a dose of 1 mg/kg but not 0.1 mg/kg. In a test of conditioned taste aversion, GSK1521498 (3 mg/kg) reduced sucrose consumption 24 h following exposure to a conditioning injection. CONCLUSIONS Both opioid receptor antagonists reduced alcohol consumption but GK1521498 has higher intrinsic efficacy than naltrexone

Interactive Effects of Flow Regime, Climate Change, and Angler Harvest on Smallmouth Bass at the Southern Range Extent

The Ozark-Ouachita Interior Highlands of Arkansas, Oklahoma, and Missouri are the southern extent of native Smallmouth Bass Micropterus dolomieu range. Smallmouth Bass are an important species economically and ecologically, but it is unknown how climate change may affect them in this region and in particular how Smallmouth Bass may be affected differently across streams from various flow regimes. Here I present three projects investigating how climate change, flow regime, and angler harvest may interact to affect Smallmouth Bass over the coming century. I first modeled present and future water temperatures and calculated growth rate potential for Smallmouth Bass from streams within both groundwater and runoff flow regimes. Currently, water temperatures in runoff streams warm past optimal conditions for Smallmouth Bass during summer months and this is expected to be exacerbated by climate change. By the end of the century, my results predict that Smallmouth Bass growth could increase in winter, fall, and early spring in streams from both flow regimes, but will strongly decline during summer months in runoff streams. I next conducted an empirical study to examine differences in Smallmouth Bass body condition at present during summer months in both runoff and groundwater streams. I found in two out of three years of collections that Smallmouth Bass body condition declined during summer months in both groundwater and runoff streams with no significant difference between stream types. The final portion of my research examines population level effects of climate change on Smallmouth Bass from a runoff stream. I used empirical data to parameterize a simulation model where I simulated various climate scenarios such as increased flooding and drought probabilities. I found that increases in drought are likely to cause strong declines in adult Smallmouth Bass populations. Changes in harvest regulations could help protect Smallmouth Bass populations somewhat, but would likely not prevent population declines in the coming century. The effects of climate change on Smallmouth Bass at the southern range extent will likely be complex, but groundwater streams may mitigate some of the negative effects of climate change on Smallmouth Bass