83 resultados para Clustering and objective measures


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Because balance is not fully developed in children and studies have shown functional improvements with balance only training studies, a combination of plyometric and balance activities might enhance static balance, dynamic balance, and power. The objective of this study was to compare the effectiveness of plyometric only (PLYO) with balance and plyometric (COMBINED) training on balance and power measures in children. Before and after an 8-week training period, testing assessed lower-body strength (1 repetition maximum leg press), power (horizontal and vertical jumps, triple hop for distance, reactive strength, and leg stiffness), running speed (10-m and 30-m sprint), static and dynamic balance (Standing Stork Test and Star Excursion Balance Test), and agility (shuttle run). Subjects were randomly divided into 2 training groups (PLYO [n = 14] and COMBINED [n = 14]) and a control group (n = 12). Results based on magnitude-based inferences and precision of estimation indicated that the COMBINED training group was considered likely to be superior to the PLYO group in leg stiffness (d = 0.69, 91% likely), 10-m sprint (d = 0.57, 84% likely), and shuttle run (d = 0.52, 80% likely). The difference between the groups was unclear in 8 of the 11 dependent variables. COMBINED training enhanced activities such as 10-m sprints and shuttle runs to a greater degree. COMBINED training could be an important consideration for reducing the high velocity impacts of PLYO training. This reduction in stretch-shortening cycle stress on neuromuscular system with the replacement of balance and landing exercises might help to alleviate the overtraining effects of excessive repetitive high load activities.

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Whereas muscle potentiation is consistently demonstrated with evoked contractile properties, the potentiation of functional and physiological measures is inconsistent. The objective was to compare a variety of conditioning stimuli volumes and intensities over a 15-min recovery period. Twelve volleyball players were subjected to conditioning stimuli that included 10 repetitions of half squats with 70% of 1-repetition maximum (RM) (10 × 70), 5 × 70, 5 × 85, 3 × 85, 3 × 90, 1 × 90, and control. Jump height, power, velocity, and force were measured at baseline, 1, 3, 5, 10, and 15 min. Data were analysed with a 2-way repeated measure ANOVA and magnitude-based inferences. The ANOVA indicated significant decreases in jump height, power, and velocity during recovery. This should not be interpreted that no potentiation occurred. Each dependent variable reached a peak at a slightly different time: peak jump height (2.8 ± 2.3 min), mean power (3.6 ± 3.01 min), peak power (2.5 ± 1.8 min), and peak velocity (2.5 ± 1.8 min). Magnitude-based inference revealed that both the 5 × 70 and 3 × 85 protocol elicited changes that exceeded 75% likelihood of exceeding the smallest worthwhile change (SWC) for peak power and velocity. The 10 × 70 and the 5 × 70 had a substantial likelihood of potentiating peak velocity and mean power above the SWC, respectively. Magnitude-based inferences revealed that while no protocol had a substantial likelihood of potentiating the peak vertical jump, the 5 × 70 had the most consistent substantial likelihood of increasing the peak of most dependent variables. We were unable to consistently predict if these peaks occurred at 1, 3, or 5 min poststimulation, though declines after 5 min seems probable.

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Recent development of characterisation techniques and computer simulation has extended our ability to access atomic scale information regarding materials microstructure evolution. New results from such techniques have significantly progressed our knowledge about solute behaviour during the earliest stages of decomposition of the solid solution. This chapter updates current understanding about solute clustering and discusses the effect of solute clustering and micro-alloying on precipitate microstructure evolution in aluminium alloys. In addition, a brief review is given on the effect of severe plastic deformation on precipitate evolution in Al alloys.

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PURPOSE: Understanding factors that influence accurate assessment of physical activity (PA) and sedentary behavior (SB) is important to measurement development, epidemiologic studies, and interventions. This study examined agreement between self-reported (International Physical Activity Questionnaire-Long Form [IPAQ-LF]) and accelerometry-based estimates of PA and SB across six countries and identified correlates of between-method agreement. METHODS: Self-report and objective (accelerometry-based) PA and SB data were collected in 2002-2011 from 3865 adult participants in eight cities from six countries (Belgium, Czech Republic, Denmark, Spain, United Kingdom, and United States). Between-method relative agreement (correlation) and absolute disagreement (mean difference between conceptually and intensity-matched IPAQ-LF and accelerometry-based PA and SB variables) were estimated. Also, sociodemographic characteristics and PA patterns were examined as correlates of between-method agreement. RESULTS: Observed relative agreement (relationships of IPAQ-LF with accelerometry-based PA and SB variables) was small to moderate (r = 0.05-0.37) and was moderated by sociodemographic (age, sex, weight status, and education) and behavioral (PA-type) factors. The absolute disagreement was large, with participants self-reporting higher PA intensity and total time in moderate-to-vigorous-intensity PA than accelerometry. Also, self-reported sitting time was lower than accelerometry-based sedentary behavior. After adjusting for sociodemographic and behavioral factors, the absolute disagreement between pairs of IPAQ-LF and accelerometry-based PA variables remained significantly different across cities/countries. CONCLUSIONS: Present findings suggest systematic cultural and/or linguistic and sociodemographic differences in absolute agreement between the IPAQ-LF and the accelerometry-based PA and SB variables. These results have implications for the interpretation of international PA and SB data and correlate/determinant studies. They call for further efforts to improve such measures.

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Analysis of crowd behaviour in public places is an indispensable tool for video surveillance. Automated detection of anomalous crowd behaviour is a critical problem with the increase in human population. Anomalous events may include a person loitering about a place for unusual amounts of time; people running and causing panic; the size of a group of people growing over time etc. In this work, to detect anomalous events and objects, two types of feature coding has been proposed: spatial features and spatio-temporal features. Spatial features comprises of contrast, correlation, energy and homogeneity, which are derived from Gray Level Co-occurrence Matrix (GLCM). Spatio-temporal feature includes the time spent by an object at different locations in the scene. Hyperspherical clustering has been employed to detect the anomalies. Spatial features revealed the anomalous frames by using contrast and homogeneity measures. Loitering behaviour of the people were detected as anomalous objects using the spatio-temporal coding.

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BACKGROUND: Measuring and monitoring the true prevalence of risk factors for chronic conditions is essential for evidence-based policy and health service planning. Understanding the prevalence of risk factors for cardiovascular disease (CVD) in Australia relies heavily on self-report measures from surveys, such as the triennial National Health Survey. However, international evidence suggests that self-reported data may substantially underestimate actual risk factor prevalence. This study sought to characterise the extent of misreporting in a large, nationally-representative health survey that included objective measures of clinical risk factors for CVD.

METHODS: This study employed a cross-sectional analysis of 7269 adults aged 18 years and over who provided fasting blood samples as part of the 2011-12 Australian Health Survey. Self-reported prevalence of high blood pressure, high cholesterol and diabetes was compared to measured prevalence, and univariate and multivariate logistic regression analyses identified socio-demographic characteristics associated with underreporting for each risk factor.

RESULTS: Approximately 16 % of the total sample underreported high blood pressure (measured to be at high risk but didn't report a diagnosis), 33 % underreported high cholesterol, and 1.3 % underreported diabetes. Among those measured to be at high risk, 68 % did not report a diagnosis for high blood pressure, nor did 89 % of people with high cholesterol and 29 % of people with high fasting plasma glucose. Younger age was associated with underreporting high blood pressure and high cholesterol, while lower area-level disadvantage and higher income were associated with underreporting diabetes.

CONCLUSIONS: Underreporting has important implications for CVD risk factor surveillance, policy planning and decisions, and clinical best-practice guidelines. This analysis highlights concerns about the reach of primary prevention efforts in certain groups and implications for patients who may be unaware of their disease risk status.

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OBJECTIVE: To validate the Meaning in Life Questionnaire (MLQ) in earlier and later older-adulthood, and examine its correlates. METHOD: Participants in earlier (n = 341, M age = 68.5) and later older-adulthood (n = 341, M age = 78.6) completed the MLQ and other measures. Confirmatory multigroup analysis, correlations, and regression models were conducted. RESULTS: A two-factor (presence and search), eight-item model of the MLQ had a good fit and was age-invariant. Presence and search for meaning were largely unrelated. Meaning was associated with life satisfaction, well-being across a range of domains, and psychological resources. Searching for meaning correlated negatively with these variables, but to a lesser degree in later older-adulthood. DISCUSSION: The MLQ is valid in older-adulthood. Meaning in life is psychologically adaptive in older-adulthood. Searching for meaning appears less important, especially in later older-adulthood. Findings are discussed in the context of aging and psychosocial development.

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BackgroundChildren's exposure to other people's cigarette smoke (environmental tobacco smoke, or ETS) is associated with a range of adverse health outcomes for children. Parental smoking is a common source of children's exposure to ETS. Older children are also at risk of exposure to ETS in child care or educational settings. Preventing exposure to cigarette smoke in infancy and childhood has significant potential to improve children's health worldwide.ObjectivesTo determine the effectiveness of interventions aiming to reduce exposure of children to ETS.Search methodsWe searched the Cochrane Tobacco Addiction Group Specialized Register and conducted additional searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, EMBASE, CINAHL, ERIC, and The Social Science Citation Index & Science Citation Index (Web of Knowledge). Date of the most recent search: September 2013.Selection criteriaControlled trials with or without random allocation. Interventions must have addressed participants (parents and other family members, child care workers and teachers) involved with the care and education of infants and young children (aged 0 to 12 years). All mechanisms for reduction of children's ETS exposure, and smoking prevention, cessation, and control programmes were included. These include health promotion, social-behavioural therapies, technology, education, and clinical interventions.Data collection and analysisTwo authors independently assessed studies and extracted data. Due to heterogeneity of methodologies and outcome measures, no summary measures were possible and results were synthesised narratively.Main resultsFifty-seven studies met the inclusion criteria. Seven studies were judged to be at low risk of bias, 27 studies were judged to have unclear overall risk of bias and 23 studies were judged to have high risk of bias. Seven interventions were targeted at populations or community settings, 23 studies were conducted in the 'well child' healthcare setting and 24 in the 'ill child' healthcare setting. Two further studies conducted in paediatric clinics did not make clear whether the visits were to well or ill children, and another included both well and ill child visits. Thirty-six studies were from North America, 14 were in other high income countries and seven studies were from low- or middle-income countries. In only 14 of the 57 studies was there a statistically significant intervention effect for child ETS exposure reduction. Of these 14 studies, six used objective measures of children's ETS exposure. Eight of the studies had a high risk of bias, four had unclear risk of bias and two had a low risk of bias. The studies showing a significant effect used a range of interventions: seven used intensive counselling or motivational interviewing; a further study used telephone counselling; one used a school-based strategy; one used picture books; two used educational home visits; one used brief intervention and one study did not describe the intervention. Of the 42 studies that did not show a significant reduction in child ETS exposure, 14 used more intensive counselling or motivational interviewing, nine used brief advice or counselling, six used feedback of a biological measure of children's ETS exposure, one used feedback of maternal cotinine, two used telephone smoking cessation advice or support, eight used educational home visits, one used group sessions, one used an information kit and letter, one used a booklet and no smoking sign, and one used a school-based policy and health promotion. In 32 of the 57 studies, there was reduction of ETS exposure for children in the study irrespective of assignment to intervention and comparison groups. One study did not aim to reduce children's tobacco smoke exposure, but rather aimed to reduce symptoms of asthma, and found a significant reduction in symptoms in the group exposed to motivational interviewing. We found little evidence of difference in effectiveness of interventions between the well infant, child respiratory illness, and other child illness settings as contexts for parental smoking cessation interventions.Authors' conclusionsWhile brief counselling interventions have been identified as successful for adults when delivered by physicians, this cannot be extrapolated to adults as parents in child health settings. Although several interventions, including parental education and counselling programmes, have been used to try to reduce children's tobacco smoke exposure, their effectiveness has not been clearly demonstrated. The review was unable to determine if any one intervention reduced parental smoking and child exposure more effectively than others, although seven studies were identified that reported motivational interviewing or intensive counselling provided in clinical settings was effective.