22 research outputs found
Exoplanet diversity in the era of space-based direct imaging missions
Community White Paper: submitted to the National Academy of Sciences Exoplanet Science StrategyThis white paper discusses the diversity of exoplanets that could be detected by future observations, so that comparative exoplanetology can be performed in the upcoming era of large space-based flagship missions. The primary focus will be on characterizing Earth-like worlds around Sun-like stars. However, we will also be able to characterize companion planets in the system simultaneously. This will not only provide a contextual picture with regards to our Solar system, but also presents a unique opportunity to observe size dependent planetary atmospheres at different orbital distances. We propose a preliminary scheme based on chemical behavior of gases and condensates in a planet's atmosphere that classifies them with respect to planetary radius and incident stellar flux
Structural neuroimaging biomarkers for obsessive-compulsive disorder in the ENIGMA-OCD consortium: medication matters
No diagnostic biomarkers are available for obsessive-compulsive disorder (OCD). Here, we aimed to identify magnetic resonance imaging (MRI) biomarkers for OCD, using 46 data sets with 2304 OCD patients and 2068 healthy controls from the ENIGMA consortium. We performed machine learning analysis of regional measures of cortical thickness, surface area and subcortical volume and tested classification performance using cross-validation. Classification performance for OCD vs. controls using the complete sample with different classifiers and cross-validation strategies was poor. When models were validated on data from other sites, model performance did not exceed chance-level. In contrast, fair classification performance was achieved when patients were grouped according to their medication status. These results indicate that medication use is associated with substantial differences in brain anatomy that are widely distributed, and indicate that clinical heterogeneity contributes to the poor performance of structural MRI as a disease marker
Análise de taxa metabólica basal e composição corporal de idosos do sexo masculino antes e seis meses após exercÃcios de resistência Análisis de la tasa metabolica de descanso y la composición corporal en veteranos hombres antes y despues de seis meses de ejercicio de endurance Analysis of resting metabolic rate and body composition in elderly males before and after six months of endurance exercise
O objetivo deste trabalho foi o de comparar a taxa metabólica basal e a composição corporal antes e após um programa de exercÃcio de resistência. Foram selecionados 46 voluntários do sexo masculino com idade entre 60 e 75 (66,97 ± 4,80 anos), que foram distribuÃdos aleatoriamente em dois grupos: 1) grupo controle, que foi orientado a não alterar seus hábitos rotineiros e não se engajar em nenhum programa de exercÃcio fÃsico; e 2) grupo experimental, que participou de um programa de exercÃcios em cicloergômetro três vezes por semana (60 minutos) em dias alternados por seis meses, com intensidade prescrita referente à freqüência cardÃaca do limiar ventilatório 1 (LV-1). Os voluntários foram submetidos a avaliação da composição corporal (DEXA); calorimetria indireta, análise sanguÃnea e teste ergoespirométrico. Após o perÃodo de estudo, foram observados decréscimo significativo nos hormônios tireoidianos e mudanças no metabolismo basal em ambos os grupos, mas não foram constatadas alterações na composição corporal. No entanto, o grupo experimental apresentou aumento significativo no consumo de oxigênio pico e na carga de trabalho referente à intensidade do LV-1. Os dados sugerem que um programa de exercÃcios aeróbios na intensidade do LV-1 não é suficiente para provocar alterações favoráveis no metabolismo basal e composição corporal de idosos, embora promova benefÃcios cardiovasculares.<br>El objetivo de este trabajo fué el de comparar la tasa metabólica basal y la composición corporal antes y despues de un programa de ejercicio de endurance. Fueron seleccionados 46 voluntarios del sexo masculino con edad entre 60 y 75 (66.97± 4.80 años) que fueron distribuidos aleatoriamente en 2 grupos: 1) grupo control, que fué orientado a no alterar sus hábitos rutinarios y no se encajar en ningún programa de ejercÃcio fÃsico; y 2) grupo experimental, que participó de un programa de ejercicios en cicloergometro 3 veces por semana (60 minutos) en dÃas alternados por seis meses con intensidad prescrita referente a la frecuencia cardiaca del umbral ventilatorio I (VT-1). Los voluntarios fueron sometidos a una evaluación de la composición corporal (DEXA); calorimetrÃa indirecta, análisis sanguÃneo y test ergoespirométrico. Después del perÃodo de estudio, fue observado un decrecimiento significativo en las hormonas tiroideas y cambios en el metabolismo basal en ambos grupos, pero no fueron observadas alteraciones en la composición corporal. En tanto, el grupo experimental presentó un aumento significativo en el consumo de oxigeno pico y en la carga de trabajo referente a la intensidad del VT-1. Los datos sugieren que un programa de ejercicios aeróbicos en la intensidad del VT-1 no es suficiente para provocar alteraciones favorables en el metabolismo basal y en la composición corporal de añosos, asà mismo promueva beneficios cardiovasculares.<br>The aim of this study was to compare basal metabolic rate and body composition before and after an endurance-type physical fitness program. The study involved 46 sedentary aging males, aged 60-75 (66.97 ± 4.80 years), who were randomly allocated to two groups: 1) control group, which was asked not to change their daily routine or join a regular physical fitness program; and 2) experimental group, who took part in an aerobic fitness program consisting of working on cycle ergometer three times a week (60 minutes) on alternate days for six months, at heart rate corresponding to ventilatory threshold 1 (VT-1) intensity. Subjects were submitted to measurement of body composition (DEXA); indirect calorimetry, blood analysis and ergospirometric testing. After the study period, the authors found a significant decrease in thyroid hormones as well as basal metabolism changes in both groups, but no changes in body composition. The experimental group, however, showed a significant increase in peak oxygen uptake and workload at VT-1 intensity. The data suggest that although an aerobic exercise program at VT-1 intensity is not enough to alter the basal metabolism and body composition of healthy seniors, it does lead to cardiovascular benefits
Systematic analysis of DNA damage induction and DNA repair pathway activation by continuous wave visible light laser micro-irradiation
Lower resting metabolic rate in the elderly may not be entirely due to changes in body composition
Ageing between gerontology and biomedicine
Over the past two decades, public interest in the basic biological processes underlying the phenomenon of ageing has grown considerably. New developments in biotechnology and health maintenance programmes appear to be forging new relationships between biology, medicine and the lives of older people. A number of social scientists describe the process as the ‘biomedicalization of aging’. In this article, we argue that contemporary biogerontology, an important sub-field of gerontology that could be construed as the primary actor in the process of ‘biomedicalization’, should be regarded instead as advancing a critique of biomedicine. We then provide a genealogy of the critique and close the argument by pointing to sources of uncertainty within biogerontology, which should be taken into account in any further studies of the relationship between biology, medicine and the lives of older people