Search results for "STATISTICS"
showing 10 items of 7671 documents
Testing psychological (GAM) model of aggression on the men’s sample
2021
The study was carried out to verify how psychological models are able to explain the phenomenon of aggression among men. There is a lack of research that try to test in holistic way many factors of aggression. We try to enrich the results of research on male aggression by recognizing to what extent factors that have not been studied so far, such as willpower, temporal orientation, or the use of drugs or steroids, explain aggression in the group of men. The sample of men (N = 131) was selected deliberately in terms of substance dependence, steroid use and a free substance-free howl. Ten Item Personality Inventory (TIPI) was used to measure five personality factors. The Zimbardo Time Percepti…
Development and validation of prediction model to estimate 10-year risk of all-cause mortality using modern statistical learning methods: a large pop…
2021
Abstract Background In increasingly ageing populations, there is an emergent need to develop a robust prediction model for estimating an individual absolute risk for all-cause mortality, so that relevant assessments and interventions can be targeted appropriately. The objective of the study was to derive, evaluate and validate (internally and externally) a risk prediction model allowing rapid estimations of an absolute risk of all-cause mortality in the following 10 years. Methods For the model development, data came from English Longitudinal Study of Ageing study, which comprised 9154 population-representative individuals aged 50–75 years, 1240 (13.5%) of whom died during the 10-year follo…
A simplified framework to optimize MRI contrast preparation
2018
PURPOSE This article proposes a rigorous optimal control framework for the design of preparation schemes that optimize MRI contrast based on relaxation time differences. METHODS Compared to previous optimal contrast preparation schemes, a drastic reduction of the optimization parameter number is performed. The preparation scheme is defined as a combination of several block pulses whose flip angles, phase terms and inter-pulse delays are optimized to control the magnetization evolution. RESULTS The proposed approach reduces the computation time of B 0 -robust preparation schemes to around a minute (whereas several hours were required with previous schemes), with negligible performance loss. …
A twin study on the heritability of walking ability among older women
2006
BACKGROUND This study examined the role of genetic and environmental factors explaining individual differences in women's walking ability in old age. METHODS A maximal walking speed test over 10 meters and a 6-minute walking endurance test were done under standard conditions among 92 monozygotic and 105 dizygotic pairs of twin sisters reared together, aged 63-75 years. RESULTS The mean maximum walking speed was 1.73 +/- 0.32 m/s and the mean distance covered in the 6-minute walking test was 525.6 +/- 77.3 m. Multivariate genetic modeling showed that a minor part of the variances in walking speed (16%, 95% confidence interval [CI]: 0%-54%) and endurance (20%, 95% CI: 0%-56%) were accounted f…
Postural balance and health-related factors in middle-aged and older women with injurious falls and non-fallers.
2004
Background and aims: Older jailers aged over 70 years have shown impaired balance abilities, but it is unclear if impairment in balance control can be detected among jallers who are in their 50’s and 60’s. The aim oj this study was to analyze possible differences in balance control and other health-related factors between female fallers and nonfallers aged 50–68 years. Methods: Women 50–68 years of age (N=40) who had fallen outside and needed medical attention were recruited through a larger fall accident study. Non-fallers (N=97) were women representing the same age group who had not fallen during the preceding 12 months. A battery of standing force platform balance tests were administered…
Genetic and environmental influences on hearing in older women.
2007
Background. This study examined the relative contribution of genetic and environmental effects on the air-conducted hearing threshold level (0.5‐4 kHz) and speech recognition threshold level of the better ear as well as self-reported hearing in older women. Methods. Hearing was measured as a part of the Finnish Twin Study on Aging in 103 monozygotic (MZ) and 114 dizygotic (DZ) female twin pairs aged 63‐76 years. Audiometric measured hearing was tested using standardized methods in soundproof conditions. Self-reported hearing was assessed by a structured question. Quantitative genetic modeling was used for data analyses. Results. No significant differences in age, exposure to noise, hearing-…
Force Platform Balance Measures as Predictors of Indoor and Outdoor Falls in Community-Dwelling Women Aged 63-76 Years
2008
Background. Inability to maintain balance while standing increases risk of falls in older people. The present study assessed whether center of pressure (COP) movement measured with force platform technology predicts risk for falls among older people with no manifest deficiency in standing balance. Methods. Participants were 434 community-dwelling women, aged 63-76 years. COP was measured in six stances on a force platform. Following balance tests, participants reported their falls with 12 monthly calendars. Incidence rate ratios (IRR) with 95% confidence intervals (CI) were computed from negative binomial regression models. For the analysis, those with>/=1 fall indoors were coded"indoor fal…
Perinatal exposure to 5-methoxytryptamine, behavioural-stress reactivity and functional response of 5-HT1A receptors in the adolescent rat.
2008
Abstract Serotonin is involved in a wide range of physiological and patho-physiological mechanisms. In particular, 5-HT1A receptors are proposed to mediate stress-adaptation. The aim of this research was to investigate in adolescent rats: first, the consequences of perinatal exposure to 5-metoxytryptamine (5MT), a 5-HT1/5-HT2 serotonergic agonist, on behavioural-stress reactivity in elevated plus maze, open field and forced swim tests; secondly, whether the behavioural effects induced by perinatal exposure to 5MT on open field and forced swim tests were affected by the selective 5-HT1A receptor agonist LY 228729, a compound able to elicit a characteristic set of motor behaviours on these ex…
Integration of personality constructs: The role of traits and motivation in the willingness to exert effort in academic and social life domains
2014
There has been growing interest in recent years in exploring different types of personality constructs and the nature of inter-relationships between personality variables in predicting outcomes in different life domains. The present study explores how personality traits and autonomous goal motivation predict the willingness to invest effort in academic and social life domains. Using a sample of 4133 upper secondary school students in Germany, multilevel regression analyses yielded three main results. First, both personality traits and motivation were substantially related to the willingness to exert effort. Second, the mediation effect compared to the direct effect was relatively small. Thi…
Does optimism mediate the relationship between Big Five and perceived stress? A study with Spanish adolescents
2021
Los resultados de investigación han mostrado la existencia de relaciones entre los Cinco Grandes factores de personalidad, Optimismo y Estrés Percibido. El objetivo del estudio es explorar, mediante modelos de ecuaciones estructurales, el posible papel mediador que se ha sugerido podría desempeñar Optimismo en esta relación. También, se explora a través de un análisis multi-grupo la invarianza por sexo de los resultados. Un total de 611 adolescentes españoles completaron de forma anónima los cuestionarios BFQ, LOT-R y PSS. Optimismo se asoció positivamente asociado con los rasgos de personalidad y negativamente con Estrés Percibido. El Estrés se relacionó negativamente con Estabilidad Emoc…