Oxidation chemistry of d^0 organometallic complexes

Electron-transfer processes can play an important role in organometallic chemistry. Herein, we demonstrate that even d^0 organometallic complexes exhibit a rich redox chemistry and present electrochemical, kinetics, and stereochemical studies that establish a general outer-sphere oxidation process for d^0 group 4 metallocene complexes. This oxidation chemistry closely parallels the reported LMCT photochemistry of these complexes

The Teachers’ Role in Behavioral Problems of Pupils With EBD in Special Education:Teacher–Child Relationships Versus Structure

This longitudinal study examined bidirectional associations between special education pupils’ teacher–child relationship characteristics (quality, satisfaction, and conflict), classroom structure, and behavioral problems (externalizing and attention-hyperactivity). A secondary goal was to investigate the extent to which severity of behavioral problems moderated the prospective associations. Participants were 586 pupils (86% boys) in Grades 4 to 6 (Mage time 1 = 10.82 years, SD = 0.86) from 13 special education schools in the Netherlands and their teachers. Findings indicated that primarily teacher–child conflict was related to increased externalizing problems. More classroom structure was related to decreased attention-hyperactivity problems, but higher teacher–child relationship quality was linked to increases in attention-hyperactivity problems. Moreover, both types of problems were related to increases in conflict. Severity of behavior problems did not moderate these associations. Although findings were not consistent in both school years, they suggested that particularly reducing conflict and instilling more classroom structure were the most effective strategies in reducing behavioral problems. Furthermore, disrupting negative transactional associations between conflict and externalizing behavior is important to reduce externalizing behavior.</p

The Teachers’ Role in Behavioral Problems of Pupils With EBD in Special Education:Teacher–Child Relationships Versus Structure

This longitudinal study examined bidirectional associations between special education pupils’ teacher–child relationship characteristics (quality, satisfaction, and conflict), classroom structure, and behavioral problems (externalizing and attention-hyperactivity). A secondary goal was to investigate the extent to which severity of behavioral problems moderated the prospective associations. Participants were 586 pupils (86% boys) in Grades 4 to 6 (Mage time 1 = 10.82 years, SD = 0.86) from 13 special education schools in the Netherlands and their teachers. Findings indicated that primarily teacher–child conflict was related to increased externalizing problems. More classroom structure was related to decreased attention-hyperactivity problems, but higher teacher–child relationship quality was linked to increases in attention-hyperactivity problems. Moreover, both types of problems were related to increases in conflict. Severity of behavior problems did not moderate these associations. Although findings were not consistent in both school years, they suggested that particularly reducing conflict and instilling more classroom structure were the most effective strategies in reducing behavioral problems. Furthermore, disrupting negative transactional associations between conflict and externalizing behavior is important to reduce externalizing behavior.</p

Oxidation chemistry of d^0 organometallic complexes

Electron-transfer processes can play an important role in organometallic chemistry. Herein, we demonstrate that even d^0 organometallic complexes exhibit a rich redox chemistry and present electrochemical, kinetics, and stereochemical studies that establish a general outer-sphere oxidation process for d^0 group 4 metallocene complexes. This oxidation chemistry closely parallels the reported LMCT photochemistry of these complexes

Testing a Social Network Intervention Using Vlogs to Promote Physical Activity Among Adolescents: A Randomized Controlled Trial

There is a need to stimulate physical activity among adolescents, but unfortunately, they are hard to reach with traditional mass media interventions. A promising alternative is to carry out social network interventions. In social network interventions, a small group of individuals (influence agents) is selected to promote health-related behaviors within their social network. This study investigates whether a social network intervention is more effective to promote physical activity, compared to a mass media intervention and no intervention. Ad

Liquid Sucrose Consumption Promotes Obesity and Impairs Glucose Tolerance Without Altering Circulating Insulin Levels

© 2018 The Obesity Society Objective: Multiple factors contribute to the rising rates of obesity and to difficulties in weight reduction that exist in the worldwide population. Caloric intake via sugar-sweetened beverages may be influential. This study tested the hypothesis that liquid sucrose intake promotes obesity by increasing serum insulin levels and tissue lipid accumulation. Methods: C57BL/6J mice were given 30% sucrose in liquid form. Changes in weight gain, body composition, energy expenditure (EE), and tissue lipid content were measured. Results: Mice drinking sucrose gained more total body mass (TBM), had greater fat mass, and displayed impaired glucose tolerance relative to control mice. These metabolic changes occurred without alterations in circulating insulin levels and despite increases in whole body EE. Lipid accrued in liver, but not skeletal muscle, of sucrose-consuming mice. Oxygen consumption (VO2) correlated with fat-free mass and moderately with TBM, but not with fat mass. ANCOVA for treatment effects on EE, with TBM, VO2, lean body mass, and fat-free mass taken as potential covariates for EE, revealed VO2 as the most significant correlation. Conclusions: Weight gain induced by intake of liquid sucrose in mice is associated with lipid accrual in liver, but not skeletal muscle, and occurs without an increase in circulating insulin

Mother and Adolescent Reports of Associations Between Child Behavior Problems and Mother-Child Relationship Qualities: Separating Shared Variance from Individual Variance

This study contrasts results from different correlational methods for examining links between mother and child (N = 72 dyads) reports of early adolescent (M = 11.5 years) behavior problems and relationship negativity and support. Simple (Pearson) correlations revealed a consistent pattern of statistically significant associations, regardless of whether scores came from the same reporter or from different reporters. When correlations between behavior problems and relationship quality differed, within-reporter correlations were always greater in magnitude than between-reporter correlations. Dyadic (common fate) analyses designed for interdependent data decomposed within-reporter correlations into variance shared across reporters (dyadic correlations) and variance unique to specific reporters (individual correlations). Dyadic correlations were responsible for most associations between adolescent behavior problems and relationship negativity; after partitioning variance shared across reporters, no individual correlations emerged as statistically significant. In contrast, adolescent behavior problems were linked to relationship support via both shared variance and variance unique to maternal perceptions. Dyadic analyses provide a parsimonious alternative to multiple contrasts in instances when identical measures have been collected from multiple reporters. Findings from these analyses indicate that same-reporter variance bias should not be assumed in the absence of dyadic statistical analyses

Forest and woodland replacement patterns following drought-related mortality

Forest vulnerability to drought is expected to increase under anthropogenic climate change, and drought-induced mortality and community dynamics following drought have major ecological and societal impacts. Here, we show that tree mortality concomitant with drought has led to short-term (mean 5 y, range 1 to 23 y after mortality) vegetation-type conversion in multiple biomes across the world (131 sites). Self-replacement of the dominant tree species was only prevalent in 21% of the examined cases and forests and woodlands shifted to nonwoody vegetation in 10% of them. The ultimate temporal persistence of such changes remains unknown but, given the key role of biological legacies in long-term ecological succession, this emerging picture of postdrought ecological trajectories highlights the potential for major ecosystem reorganization in the coming decades. Community changes were less pronounced under wetter postmortality conditions. Replacement was also influenced by management intensity, and postdrought shrub dominance was higher when pathogens acted as codrivers of tree mortality. Early change in community composition indicates that forests dominated by mesic species generally shifted toward more xeric communities, with replacing tree and shrub species exhibiting drier bioclimatic optima and distribution ranges. However, shifts toward more mesic communities also occurred and multiple pathways of forest replacement were observed for some species. Drought characteristics, species-specific environmental preferences, plant traits, and ecosystem legacies govern postdrought species turnover and subsequent ecological trajectories, with potential far-reaching implications for forest biodiversity and ecosystem services.Additional co-authors: Lucía Galiano, Joseph L. Ganey, Patrick Gonzalez, Anna L. Jacobsen, Jeffrey Michael Kane, Thomas Kitzberger, Juan C. Linares, Suzanne B. Marchetti, George Matusick, Michael Michaelian, Rafael M. Navarro-Cerrillo, Robert Brandon Pratt, Miranda D. Redmond, Andreas Rigling, Francesco Ripullone, Gabriel Sangüesa-Barreda, Yamila Sasal, Sandra Saura-Mas, Maria Laura Suarez, Thomas T. Veblen, Caroline Vincke, and Ben Zeema

Risk Factors for Cervical Precancer and Cancer in HIV-Infected, HPV-Positive Rwandan Women

Although cervical cancer is an AIDS-defining condition, infection with human immunodeficiency virus (HIV) may only modestly increase the risk of cervical cancer. There is a paucity of information regarding factors that influence the natural history of human papillomavirus (HPV) in HIV-infected women. We examined factors associated with cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) in Rwandan women infected with both HIV and HPV (HIV+/HPV+).In 2005, 710 HIV+ Rwandan women ≥25 years enrolled in an observational cohort study; 476 (67%) tested HPV+. Each woman provided sociodemographic data, CD4 count, a cervical cytology specimen and cervicovaginal lavage (CVL), which was tested for >40 HPV genotypes by MY09/MY11 PCR assay. Logistic regression models calculated odds ratios (OR) and 95% confidence intervals (CI) of associations of potential risk factors for CIN3+ among HIV+/HPV+ women.Of the 476 HIV+/HPV+ women 42 (8.8%) were diagnosed with CIN3+. Factors associated with CIN3+ included ≥7 (vs. 0-2) pregnancies, malarial infection in the previous six months (vs. never), and ≥7 (vs. 0-2) lifetime sexual partners. Compared to women infected by non-HPV16 carcinogenic HPV genotypes, HPV16 infection was positively associated and non-carcinogenic HPV infection was inversely associated with CIN3+. CD4 count was significantly associated with CIN3+ only in analyses of women with non-HPV16 carcinogenic HPV (OR = 0.62 per 100 cells/mm(3), CI = 0.40-0.97).In this HIV+/HPV+ population, lower CD4 was significantly associated with CIN3+ only in women infected with carcinogenic non-HPV16. We found a trend for higher risk of CIN3+ in HIV+ women reporting recent malarial infection; this association should be investigated in a larger group of HIV+/HPV+ women