Radicals, Metals and Magnetism

The interaction between unpaired electrons governs many physical properties of materials. Although in a fundamental sense the interaction is simple, a full understanding of the interaction in molecular systems is complicated by the presence of other bonding and non-bonding electrons. The resulting many body problem is very challenging. Nevertheless, much qualitative understanding can be obtained from applying simple molecular orbital theory and considering only the partly filled orbitals. The resulting model can be used to describe existing diradical and metal-radical systems and also has predicative value in the search for molecular magnets and design of nanoscale devices

Potential for Abrupt Changes in Atmospheric Methane

Methane (CH4) is the second most important greenhouse gas that humans directly influence, carbon dioxide (CO2) being first. Concerns about methane’s role in abrupt climate change stem primarily from (1) the large quantities of methane stored as solid methane hydrate on the sea floor and to a lesser degree in terrestrial sediments, and the possibility that these reservoirs could become unstable in the face of future global warming, and (2) the possibility of large-scale conversion of frozen soil in the high- latitude Northern Hemisphere to methane producing wetland, due to accelerated warming at high latitudes. This chapter summarizes the current state of knowledge about these reservoirs and their potential for forcing abrupt climate change

Influence of parental attitudes on substance consumption in adolescence

The aim of this quantitative cross-sectional study was to analyze the relationship between the perception of adolescents about their tendency to use psychoactive substances and their parents' attitudes. 487 Brazilian adolescents participated. For statistical analysis the Multinomial Logit Model was used, where the Stepwise method for selecting variables was applied. Tobacco, alcohol and marijuana were related to the variables of greatest influence on the use, abuse and dependence of these substances. Findings showed that an unloving father increases the possibility that the child becomes tobacco dependent (p = 0.001). An unloving mother is most likely to have a tobacco dependent child (p = 0.001). Father's control is a protective factor for experimenting with tobacco smoking (p = 0.023) and for marijuana dependence (p = 0.042). The relationship between substance consumption in adolescence and the perception young people have about their parents' attitudes was emphasized.El objetivo de este estudio transversal cuantitativo fue analizar la relación entre la percepción del adolescente sobre su tendencia al uso de sustancias psicoactivas y las actitudes de sus padres. Participaron 487 adolescentes brasileños. Para el análisis estadístico se utilizó el Modelo Logístico Multinomial, en el que se aplicaba el método Stepwise para la selección de variables. El tabaco, el alcohol y la marihuana se relacionaron con las variables de mayor influencia en el uso, abuso y dependencia. Se encontró que un padre poco cariñoso aumenta la posibilidad de que el niño sea dependiente del tabaco (p = 0.001), al igual que una madre poco afectuosa tiene más probabilidades de tener un hijo dependiente del tabaco (p = 0.001). El control del padre es un factor protector para la experimentación del tabaco (p = 0.023) y para la dependencia de la marihuana (p = 0.042). Se puso de relieve la relación entre el consumo de las drogas en la adolescencia y la percepción que los jóvenes tienen de las actitudes de sus padres.Este estudo transversal quantitativo objetivou analisar a relação entre a percepção do adolescente sobre as atitudes parentais e sua tendência ao uso de substâncias psicoativas. Participaram 487 adolescentes brasileiros. Para análise estatística foi utilizado o Modelo Logístico Multinomial, sobre o qual se aplicou o método Stepwise para seleção de variáveis. O tabaco, o álcool e a maconha foram relacionados com as variáveis de maior influência no uso, abuso ou dependência. Verificou-se que um pai pouco afetivo, aumenta a chance de o filho ser dependente de tabaco (p = 0.001). A mãe sendo pouco afetiva tem maior possibilidade de ter um filho dependente do tabaco (p = 0.001). O controle do pai é um fator protetivo para a experimentação do tabaco (p = 0.023) e para a dependência da maconha (p = 0.042). A relação entre o uso de drogas na adolescência e a percepção que o jovem tem das atitudes de seus pais ficou evidenciada

Natural history of falls in an incident cohort of Parkinson’s disease: early evolution, risk and protective features

The natural history of falls in early Parkinson’s disease (PD) is poorly understood despite the profound effect of falls on outcome. The primary aim of this study was to describe the natural history of falls, and characterise fallers over 54 months in 99 newly diagnosed people with PD. Seventy-nine (79.7%) participants fell over 54 months and 20 (20.3%) remained falls-naïve. Twenty six (26.2%) reported retrospective falls at baseline. Gait outcomes, disease severity and self-efficacy significantly discriminated across groups. Subjective cognitive complaints emerged as the only significant cognitive predictor. Without exception, outcomes were better for non-fallers compared with fallers at any time point. Between group differences for 54 month fallers and non-fallers were influenced by the inclusion of retrospective fallers and showed a broader range of discriminant characteristics, notably stance time variability and balance self-efficacy. Single fallers (n = 7) were significantly younger than recurrent fallers (n = 58) by almost 15 years (P = 0.013). Baseline performance in early PD discriminates fallers over 54 months, thereby identifying those at risk of falls. Clinical profiles for established and emergent fallers are to some extent distinct. These results reiterate the need for timely interventions to improve postural control and gait

Natural history of falls in an incident cohort of Parkinson’s disease: early evolution, risk and protective features

The natural history of falls in early Parkinson’s disease (PD) is poorly understood despite the profound effect of falls on outcome. The primary aim of this study was to describe the natural history of falls, and characterise fallers over 54 months in 99 newly diagnosed people with PD. Seventy-nine (79.7%) participants fell over 54 months and 20 (20.3%) remained falls-naïve. Twenty six (26.2%) reported retrospective falls at baseline. Gait outcomes, disease severity and self-efficacy significantly discriminated across groups. Subjective cognitive complaints emerged as the only significant cognitive predictor. Without exception, outcomes were better for non-fallers compared with fallers at any time point. Between group differences for 54 month fallers and non-fallers were influenced by the inclusion of retrospective fallers and showed a broader range of discriminant characteristics, notably stance time variability and balance self-efficacy. Single fallers (n = 7) were significantly younger than recurrent fallers (n = 58) by almost 15 years (P = 0.013). Baseline performance in early PD discriminates fallers over 54 months, thereby identifying those at risk of falls. Clinical profiles for established and emergent fallers are to some extent distinct. These results reiterate the need for timely interventions to improve postural control and gait

Formation, contraction, and mechanotransduction of myofribrils in cardiac development: clues from genetics

Congenital heart disease (CHD) is the most common birth defect in humans. It is a leading infant mortality factor worldwide, caused by defective cardiac development. Mutations in transcription factors, signalling and structural molecules have been shown to contribute to the genetic component of CHD. Recently, mutations in genes encoding myofibrillar proteins expressed in the embryonic heart have also emerged as an important genetic causative factor of the disease, which implies that the contraction of the early heart primordium contributes to its morphogenesis. This notion is supported by increasing evidence suggesting that not only contraction but also formation, mechanosensing, and mechanotransduction of the cardiac myofibrillar proteins influence heart development. In this paper, we summarize the genetic clues supporting this idea

The influence of scribe mark pattern on perceived rotation of toric soft contact lenses

This study examined the effect of toric lens scribe mark designs on the perceived angle of rotation. Forty seven novice observers viewed video of 10 presentations for each of the seven lens designs. Overall, observers underestimated angles of rotation and no single lens design was more accurately estimated than any other. When horizontal vs. vertical lens designs were compared, the horizontal lenses were underestimated less than the vertical. Gender did not influence axis estimations

Compulsive Buying and Quality of Life: An Estimate of the Monetary Cost of Compulsive Buying Among Adults in Early Midlife

The aims of this study were to examine the associations between compulsive buying and quality of life and to estimate the monetary cost of compulsive buying for a cohort of men and women at mean age 43. Participants came from a community-based random sample of residents in two New York counties (N=548). The participants were followed from adolescence to early midlife. The mean age of participants at the most recent interview was 43.0 (SD=2.8). Fifty five percent of the participants were females. Over 90% of the participants were white. Linear regression analyses showed that compulsive buying was significantly associated with quality of life, despite controlling for relevant demographic and psychosocial factors. The estimated monetary cost of compulsive buying for this cohort was significant. The fact that the monetary cost of CB is not trivial suggests that individuals are both consciously and unconsciously plagued by their CB. The findings are important for interventionists and clinicians for cost-effective intervention and treatment programs