Standard cell electrical and physical variability analysis based on automatic physical measurement for design-for-manufacturing purposes

NASA Astrophysics Data System (ADS)

Shauly, Eitan; Parag, Allon; Khmaisy, Hafez; Krispil, Uri; Adan, Ofer; Levi, Shimon; Latinski, Sergey; Schwarzband, Ishai; Rotstein, Israel

2011-04-01

A fully automated system for process variability analysis of high density standard cell was developed. The system consists of layout analysis with device mapping: device type, location, configuration and more. The mapping step was created by a simple DRC run-set. This database was then used as an input for choosing locations for SEM images and for specific layout parameter extraction, used by SPICE simulation. This method was used to analyze large arrays of standard cell blocks, manufactured using Tower TS013LV (Low Voltage for high-speed applications) Platforms. Variability of different physical parameters like and like Lgate, Line-width-roughness and more as well as of electrical parameters like drive current (Ion), off current (Ioff) were calculated and statistically analyzed, in order to understand the variability root cause. Comparison between transistors having the same W/L but with different layout configurations and different layout environments (around the transistor) was made in terms of performances as well as process variability. We successfully defined "robust" and "less-robust" transistors configurations, and updated guidelines for Design-for-Manufacturing (DfM).

Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study

USDA-ARS?s Scientific Manuscript database

BACKGROUND: Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphism...

Connecting the dots between math and reality: A study of critical thinking in high school physics

NASA Astrophysics Data System (ADS)

Loper, Timothy K.

The purpose of this mixed method study was to discover whether training in understanding relationships between variables would help students read and interpret equations for the purposes of problem solving in physics. Twenty students from two physics classes at a private Catholic high school participated in a one group pretest-posttest unit with the conceptually based mathematical intervention being the independent variable, and the test results being the dependent variable for the quantitative portion of the study. A random sample of students was interviewed pre and post intervention for the qualitative portion of the study to determine both how their understanding of equations changed and how their approach to the problems changed. The paired-sample t test showed a significant improvement on the Physics Critical Thinking test at the p<.01 alpha level; furthermore, the interview data indicated the students displayed a deeper understanding of equations and their purpose as opposed to the superficial understanding they had before the intervention.

Influence of muscle strength, physical activity and weight on bone mass in a population-based sample of 1004 elderly women.

PubMed

Gerdhem, P; Ringsberg, K A M; Akesson, K; Obrant, K J

2003-09-01

High physical activity level has been associated with high bone mass and low fracture risk and is therefore recommended to reduce fractures in old age. The aim of this study was to estimate the effect of potentially modifiable variables, such as physical activity, muscle strength, muscle mass and weight, on bone mass in elderly women. The influence of isometric thigh muscle strength, self-estimated activity level, body composition and weight on bone mineral density (dual energy X-ray absorptiometry; DXA) in total body, hip and spine was investigated. Subjects were 1004 women, all 75 years old, taking part in the Malmö Osteoporosis Prospective Risk Assessment (OPRA) study. Physical activity and muscle strength accounted for 1-6% of the variability in bone mass, whereas weight, and its closely associated variables lean mass and fat mass, to a much greater extent explained the bone mass variability. We found current body weight to be the variable with the most substantial influence on the total variability in bone mass (15-32% depending on skeletal site) in a forward stepwise regression model. Our findings suggest that in elderly women, the major fracture-preventive effect of physical activity is unlikely to be mediated through increased bone mass. Retaining or even increasing body weight is likely to be beneficial to the skeleton, but an excess body weight increase may have negative effects on health. Nevertheless, training in elderly women may have advantages by improving balance, co-ordination and mobility and therefore decreasing the risk of fractures.

Physical activity and its relationship with perceived environment among adults living in a region of low socioeconomic level.

PubMed

Florindo, Alex Antonio; Salvador, Emanuel Péricles; Reis, Rodrigo Siqueira

2013-05-01

The environment has a great influence on people's lifestyles and their capacity to choose healthy habits. The aim of this study was to investigate the association between perceived environment and physical activity among adults living in the city of São Paulo, Brazil. This was a cross-sectional population-based study conducted with 890 people age 18 years or over. Physical activity was measured through the International Physical Activity Questionnaire (IPAQ; long version) and perceived environment was evaluated using the Neighborhood Walkability Scale (NEWS) adapted. Poisson's regression was used for statistical analyses and prevalence ratios were calculated. The outcome variable was the attainment of at least 150 minutes per week of physical activities. The independent variables consisted of perceived environment variables and control variables (sex, age, schooling, time living in the home, and number of cars per household). The perceived environment variables that explained physical activity were: receiving invitations from friends for activities (P = .012), low environmental pollution scores (p trend = 0.030) and high general safety scores (P-trend = 0.039). These results suggest that physical activity promotion in regions like this should be envisaged as a complex phenomenon and investments in public safety, prevention and combating of environmental pollution and social support networks are needed.

Regional Community Climate Simulations with variable resolution meshes in the Community Earth System Model

NASA Astrophysics Data System (ADS)

Zarzycki, C. M.; Gettelman, A.; Callaghan, P.

2017-12-01

Accurately predicting weather extremes such as precipitation (floods and droughts) and temperature (heat waves) requires high resolution to resolve mesoscale dynamics and topography at horizontal scales of 10-30km. Simulating such resolutions globally for climate scales (years to decades) remains computationally impractical. Simulating only a small region of the planet is more tractable at these scales for climate applications. This work describes global simulations using variable-resolution static meshes with multiple dynamical cores that target the continental United States using developmental versions of the Community Earth System Model version 2 (CESM2). CESM2 is tested in idealized, aquaplanet and full physics configurations to evaluate variable mesh simulations against uniform high and uniform low resolution simulations at resolutions down to 15km. Different physical parameterization suites are also evaluated to gauge their sensitivity to resolution. Idealized variable-resolution mesh cases compare well to high resolution tests. More recent versions of the atmospheric physics, including cloud schemes for CESM2, are more stable with respect to changes in horizontal resolution. Most of the sensitivity is due to sensitivity to timestep and interactions between deep convection and large scale condensation, expected from the closure methods. The resulting full physics model produces a comparable climate to the global low resolution mesh and similar high frequency statistics in the high resolution region. Some biases are reduced (orographic precipitation in the western United States), but biases do not necessarily go away at high resolution (e.g. summertime JJA surface Temp). The simulations are able to reproduce uniform high resolution results, making them an effective tool for regional climate studies and are available in CESM2.

Physical and chemical properties of pomegranate fruit accessions from Croatia.

PubMed

Radunić, Mira; Jukić Špika, Maja; Goreta Ban, Smiljana; Gadže, Jelena; Díaz-Pérez, Juan Carlos; MacLean, Dan

2015-06-15

The objective was to evaluate physical and chemical properties of eight pomegranate accessions (seven cultivars and one wild genotype) collected from the Mediterranean region of Croatia. Accessions showed high variability in fruit weight and size, calyx and peel properties, number of arils per fruit, total aril weight, and aril and juice yield. Variables that define sweet taste, such as low total acidity (TA; 0.37-0.59%), high total soluble solids content (TSS; 12.5-15.0%) and their ratio (TSS/TA) were evaluated, and results generally aligned with sweetness classifications of the fruit. Pomegranate fruit had a high variability in total phenolic content (1985.6-2948.7 mg/L). HPLC-MALDI-TOF/MS analysis showed that accessions with dark red arils had the highest total anthocyanin content, with cyanidin 3-glucoside as the most abundant compound. Principal component analysis revealed great differences in fruit physical characteristics and chemical composition among pomegranate accessions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Health Impacts of the Built Environment: Within-Urban Variability in Physical Inactivity, Air Pollution, and Ischemic Heart Disease Mortality

PubMed Central

Hankey, Steve; Brauer, Michael

2011-01-01

Background: Physical inactivity and exposure to air pollution are important risk factors for death and disease globally. The built environment may influence exposures to these risk factors in different ways and thus differentially affect the health of urban populations. Objective: We investigated the built environment’s association with air pollution and physical inactivity, and estimated attributable health risks. Methods: We used a regional travel survey to estimate within-urban variability in physical inactivity and home-based air pollution exposure [particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5), nitrogen oxides (NOx), and ozone (O3)] for 30,007 individuals in southern California. We then estimated the resulting risk for ischemic heart disease (IHD) using literature-derived dose–response values. Using a cross-sectional approach, we compared estimated IHD mortality risks among neighborhoods based on “walkability” scores. Results: The proportion of physically active individuals was higher in high- versus low-walkability neighborhoods (24.9% vs. 12.5%); however, only a small proportion of the population was physically active, and between-neighborhood variability in estimated IHD mortality attributable to physical inactivity was modest (7 fewer IHD deaths/100,000/year in high- vs. low-walkability neighborhoods). Between-neighborhood differences in estimated IHD mortality from air pollution were comparable in magnitude (9 more IHD deaths/100,000/year for PM2.5 and 3 fewer IHD deaths for O3 in high- vs. low-walkability neighborhoods), suggesting that population health benefits from increased physical activity in high-walkability neighborhoods may be offset by adverse effects of air pollution exposure. Policy implications: Currently, planning efforts mainly focus on increasing physical activity through neighborhood design. Our results suggest that differences in population health impacts among neighborhoods are similar in magnitude for air pollution and physical activity. Thus, physical activity and exposure to air pollution are critical aspects of planning for cleaner, health-promoting cities. PMID:22004949

Health impacts of the built environment: within-urban variability in physical inactivity, air pollution, and ischemic heart disease mortality.

PubMed

Hankey, Steve; Marshall, Julian D; Brauer, Michael

2012-02-01

Physical inactivity and exposure to air pollution are important risk factors for death and disease globally. The built environment may influence exposures to these risk factors in different ways and thus differentially affect the health of urban populations. We investigated the built environment's association with air pollution and physical inactivity, and estimated attributable health risks. We used a regional travel survey to estimate within-urban variability in physical inactivity and home-based air pollution exposure [particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5), nitrogen oxides (NOx), and ozone (O3)] for 30,007 individuals in southern California. We then estimated the resulting risk for ischemic heart disease (IHD) using literature-derived dose-response values. Using a cross-sectional approach, we compared estimated IHD mortality risks among neighborhoods based on "walkability" scores. The proportion of physically active individuals was higher in high- versus low-walkability neighborhoods (24.9% vs. 12.5%); however, only a small proportion of the population was physically active, and between-neighborhood variability in estimated IHD mortality attributable to physical inactivity was modest (7 fewer IHD deaths/100,000/year in high- vs. low-walkability neighborhoods). Between-neighborhood differences in estimated IHD mortality from air pollution were comparable in magnitude (9 more IHD deaths/100,000/year for PM2.5 and 3 fewer IHD deaths for O3 in high- vs. low-walkability neighborhoods), suggesting that population health benefits from increased physical activity in high-walkability neighborhoods may be offset by adverse effects of air pollution exposure. Currently, planning efforts mainly focus on increasing physical activity through neighborhood design. Our results suggest that differences in population health impacts among neighborhoods are similar in magnitude for air pollution and physical activity. Thus, physical activity and exposure to air pollution are critical aspects of planning for cleaner, health-promoting cities.

Connecting the Dots between Math and Reality: A Study of Critical Thinking in High School Physics

ERIC Educational Resources Information Center

Loper, Timothy K.

2010-01-01

The purpose of this mixed method study was to discover whether training in understanding relationships between variables would help students read and interpret equations for the purposes of problem solving in physics. Twenty students from two physics classes at a private Catholic high school participated in a one group pretest-posttest unit with…

Data re-arranging techniques leading to proper variable selections in high energy physics

NASA Astrophysics Data System (ADS)

Kůs, Václav; Bouř, Petr

2017-12-01

We introduce a new data based approach to homogeneity testing and variable selection carried out in high energy physics experiments, where one of the basic tasks is to test the homogeneity of weighted samples, mainly the Monte Carlo simulations (weighted) and real data measurements (unweighted). This technique is called ’data re-arranging’ and it enables variable selection performed by means of the classical statistical homogeneity tests such as Kolmogorov-Smirnov, Anderson-Darling, or Pearson’s chi-square divergence test. P-values of our variants of homogeneity tests are investigated and the empirical verification through 46 dimensional high energy particle physics data sets is accomplished under newly proposed (equiprobable) quantile binning. Particularly, the procedure of homogeneity testing is applied to re-arranged Monte Carlo samples and real DATA sets measured at the particle accelerator Tevatron in Fermilab at DØ experiment originating from top-antitop quark pair production in two decay channels (electron, muon) with 2, 3, or 4+ jets detected. Finally, the variable selections in the electron and muon channels induced by the re-arranging procedure for homogeneity testing are provided for Tevatron top-antitop quark data sets.

Interannual variability of high ice cloud properties over the tropics

NASA Astrophysics Data System (ADS)

Tamura, S.; Iwabuchi, H.

2015-12-01

The El Niño/Southern Oscillation (ENSO) affects atmospheric conditions and cloud physical properties such as cloud fraction (CF) and cloud top height (CTH). However, an impact of the ENSO on physical properties in high-ice cloud is not well known. Therefore, this study attempts to reveal relationship between variability of ice cloud physical properties and ENSO. Ice clouds are inferred with the multiband IR method in this study. Ice clouds are categorized in terms of cloud optical thickness (COT) as thin (0.1< COT <0.3), opaque (0.3< COT <3.6), thick (3.6< COT <11), and deep convective (DC) (11< COT) clouds, and relationship between ENSO and interannual variability of cloud physical properties is investigated for each category during the period from January 2003 to December 2014. The deseasonalized anomalies of CF and CTH in all categories correlate well with Niño3.4 index, with positive anomaly over the eastern Pacific and negative anomaly over the western Pacific during El Niño condition. However, the global distribution of these correlation coefficients is different by cloud categories. For example, CF of DC correlates well with Niño3.4 index over the convergence zone, while, that of thin cloud shows high correlation extending to high latitude from convergence zone, suggesting a connection with cloud formation. The global distributions of average rate of change differ by cloud category, because the different associate with ENSO and gradual trend toward La Niña condition had occurred over the analysis period. In this conference, detailed results and relationship between variability of cloud physical properties and atmospheric conditions will be shown.

Social cognitive correlates of leisure time physical activity among Latinos.

PubMed

Marquez, David X; McAuley, Edward

2006-06-01

Despite the well-documented benefits of leisure time physical activity, Latinos are reported to be highest among all ethnic groups in leisure time inactivity. The present study examined the relationship between leisure time physical activity and exercise self-efficacy, exercise barriers self-efficacy, exercise social support, and perceived importance of physical activity. Data were obtained from 153 Latinos (n = 86 female, n = 67 male). Comparisons were made between Latinos with high and low levels of leisure time physical activity and between men and women. Results revealed that Latinos high in leisure time physical activity had significantly greater exercise and barriers self-efficacy, received more social support from friends to exercise, and placed greater importance on physical activity outcomes than did Latinos low in leisure time physical activity. No significant differences were revealed for social support from family, nor between men and women on the psychosocial variables. Physical activity interventions targeting sources of self-efficacy, increasing social support, and emphasizing the importance of regular physical activity should be helpful in increasing leisure time physical activity of Latinos. Future research should examine the influence of environmental and cultural variables on the leisure time physical activity of Latinos and how they interact with psychosocial factors.

Prevalence of physical inactivity and associated factors among high school students from state's public schools.

PubMed

Ceschini, Fabio L; Andrade, Douglas R; Oliveira, Luis C; Araújo Júnior, Jorge F; Matsudo, Victor K R

2009-01-01

To describe the prevalence of physical inactivity and associated factors among high school students from state's public schools in the city of São Paulo, state of São Paulo, Brazil. Sixteen state's public schools were randomly selected according to the geographic areas of the city (North, South, East, and West). The sample consisted of 3,845 high school students in 2006. Physical inactivity was measured using the International Physical Activity Questionnaire (short IPAQ) and was defined as practicing moderate and/or vigorous physical activity for a period of less than 300 minutes per week. The independent variables analyzed were: gender, age, socioeconomic level, geographic area of the city, awareness of the Agita São Paulo program, participation in physical education classes, smoking, alcohol intake and time spent per day watching television. Three-level Poisson regression was used for assessing the variables, with a significance level of p < 0.05. The general prevalence of physical inactivity among adolescents in São Paulo was 62.5% (95%CI 60.5-64.1). The factors associated with physical inactivity were gender, age, socioeconomic level, geographic area of the city, awareness of the Agita São Paulo program, non-participation in physical education classes, smoking, alcohol intake and time spent per day watching television. It was concluded that the prevalence of physical inactivity among adolescents in São Paulo was high in all the geographic areas evaluated, and that sociodemographic and behavioral factors contributed significantly to physical inactivity.

Leisure time physical activity and sedentary behavior and substance use among in-school adolescents in eight African countries.

PubMed

Peltzer, Karl

2010-12-01

Physical inactivity leads to higher morbidity and mortality from chronic non-communicable diseases. In high income countries, studies have measured school population level physical activity and substance use, but comparable data are lacking from most African countries. To study the relationship between self-reported leisure time physical activity frequency and sedentary behavior and alcohol, tobacco, and other drug use behaviors among school children. A cross-sectional survey was conducted with the total sample of 24,593 school children aged 13 to 15 years from nationally representative samples from eight African countries. Univariate and multivariate analyses were conducted to assess the relationship between physical activity frequency, six measures of alcohol, tobacco, and other drug use, socioeconomic status, and mental health variables. In all, only 14.2% of the school children were frequently physically active (5 days and more in a week, at least 60 min/day) during leisure time; this was significantly higher among boys than girls. Ugandan and Kenyan school children were most physically active (17.7% and 16.0%, respectively), and Zambian and Senegalese the least (9.0% and 10.9%, respectively). Frequency of alcohol consumption and higher socioeconomic status were significantly associated with leisure time physical activity, while tobacco, illicit drug use, and mental health variables were not. Leisure time sedentary behavior of five and more hours spent sitting on a usual day were highly associated with all substance use variables. These findings suggest that leisure time physical activity frequency is associated with frequency of alcohol use and not with tobacco and illicit drug use, and leisure time sedentary behavior is highly associated with alcohol, tobacco, and drug use among adolescents.

The Number of Sexual Partners and Health-Risking Sexual Behavior: Prediction from High School Entry to High School Exit

PubMed Central

Van Ryzin, Mark J.; Johnson, Amber B.; Leve, Leslie D.; Hyoun, Kim K.

2013-01-01

Precursors to adolescent health-risking sexual behavior (HRSB) were examined in a normative sample of 373 adolescents (48.0% female, n = 178). Using a variable-oriented approach, we regressed the number of sexual partners at high school exit (age 17) on parental monitoring, association with delinquent peers, romantic relationship status, problem behavior, physical maturity, and tobacco and alcohol use at high school entry (age 14); all emerged as significant predictors except alcohol use and physical maturity (we found sex differences in physical maturity and romantic relationship status, with females being more advanced in both areas). Sexual experimentation at high school entry served to partially or fully mediate the impact of these factors. A person-oriented approach, using a broader measure of HRSB, found three subgroups of adolescents: abstainers, low-risk-takers, and high-risk-takers. Results predicting membership in these groups generally followed those from the variable-oriented analysis. Implications for the prevention of HRSB and future research directions are discussed. PMID:20703789

The number of sexual partners and health-risking sexual behavior: prediction from high school entry to high school exit.

PubMed

Van Ryzin, Mark J; Johnson, Amber B; Leve, Leslie D; Kim, Hyoun K

2011-10-01

Precursors to adolescent health-risking sexual behavior (HRSB) were examined in a normative sample of 373 adolescents (48.0% female, n = 178). Using a variable-oriented approach, we regressed the number of sexual partners at high school exit (age 17) on parental monitoring, association with delinquent peers, romantic relationship status, problem behavior, physical maturity, and tobacco and alcohol use at high school entry (age 14); all emerged as significant predictors except alcohol use and physical maturity (we found sex differences in physical maturity and romantic relationship status, with females being more advanced in both areas). Sexual experimentation at high school entry served to partially or fully mediate the impact of these factors. A person-oriented approach, using a broader measure of HRSB, found three subgroups of adolescents: abstainers, low-risk-takers, and high-risk-takers. Results predicting membership in these groups generally followed those from the variable-oriented analysis. Implications for the prevention of HRSB and future research directions are discussed.

Genetic variability in krill.

PubMed

Valentine, J W; Ayala, F J

1976-02-01

We have estimated genetic variability by gel electrophoresis in three species of krill, genus Euphausia (Arthropoda: Crustacea). Genetic variability is low where trophic resources are most seasonal, and high where trophic resources are most stable. Simlar trends have been found in benthic marine invertebrates. The observed trends of genetic variability do not correlate with trends in the stability of physical environment parameters.

Match-to-match variation in physical activity and technical skill measures in professional Australian Football.

PubMed

Kempton, Thomas; Sullivan, Courtney; Bilsborough, Johann C; Cordy, Justin; Coutts, Aaron J

2015-01-01

To determine the match-to-match variability in physical activity and technical performance measures in Australian Football, and examine the influence of playing position, time of season, and different seasons on these measures of variability. Longitudinal observational study. Global positioning system, accelerometer and technical performance measures (total kicks, handballs, possessions and Champion Data rank) were collected from 33 players competing in the Australian Football League over 31 matches during 2011-2012 (N=511 observations). The global positioning system data were categorised into total distance, mean speed (mmin(-1)), high-speed running (>14.4 kmh(-1)), very high-speed running (>19.9 kmh(-1)), and sprint (>23.0 kmh(-1)) distance while player load was collected from the accelerometer. The data were log transformed to provide coefficient of variation and the between subject standard deviation (expressed as percentages). Match-to-match variability was increased for higher speed activities (high-speed running, very high-speed running, sprint distance, coefficient of variation %: 13.3-28.6%) compared to global measures (speed, total distance, player load, coefficient of variation %: 5.3-9.2%). The between-match variability was relativity stable for all measures between and within AFL seasons, with only few differences between positions. Higher speed activities (high-speed running, very high-speed running, sprint distance), but excluding mean speed, total distance and player load, were all higher in the final third phase of the season compared to the start of the season. While global measures of physical performance are relatively stable, higher-speed activities and technical measures exhibit a large degree of between-match variability in Australian Football. However, these measures remain relatively stable between positions, and within and between Australian Football League seasons. Copyright © 2013 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Success in introductory college physics: The role of gender, high school preparation, and student learning perceptions

NASA Astrophysics Data System (ADS)

Chen, Jean Chi-Jen

Physics is fundamental for science, engineering, medicine, and for understanding many phenomena encountered in people's daily lives. The purpose of this study was to investigate the relationships between student success in college-level introductory physics courses and various educational and background characteristics. The primary variables of this study were gender, high school mathematics and science preparation, preference and perceptions of learning physics, and performance in introductory physics courses. Demographic characteristics considered were age, student grade level, parents' occupation and level of education, high school senior grade point average, and educational goals. A Survey of Learning Preference and Perceptions was developed to collect the information for this study. A total of 267 subjects enrolled in six introductory physics courses, four algebra-based and two calculus-based, participated in the study conducted during Spring Semester 2002. The findings from the algebra-based physics courses indicated that participant's educational goal, high school senior GPA, father's educational level, mother's educational level, and mother's occupation in the area of science, engineering, or computer technology were positively related to performance while participant age was negatively related. Biology preparation, mathematics preparation, and additional mathematics and science preparation in high school were also positively related to performance. The relationships between the primary variables and performance in calculus-based physics courses were limited to high school senior year GPA and high school physics preparation. Findings from all six courses indicated that participant's educational goal, high school senior GPA, father's educational level, and mother's occupation in the area of science, engineering, or computer technology, high school preparation in mathematics, biology, and the completion of additional mathematics and science courses were positively related to performance. No significant performance differences were found between male and female students. However, there were significant gender differences in physics learning perceptions. Female participants tended to try to understand physics materials and relate the physics problems to real world situations while their male counterparts tended to rely on rote learning and equation application. This study found that participants performed better by trying to understand the physics material and relate physics problems to real world situations. Participants who relied on rote learning did not perform well.

The impact of dance-aerobics training on the morpho-motor status in female high-schoolers.

PubMed

Viskić-Stalec, Natasa; Stalec, Janez; Katić, Ratko; Podvorac, Durda; Katović, Darko

2007-03-01

The aim of the study was to analyze the impact of special programmed physical education including dance, aerobics and rhythmic gymnastics on the development of motor and functional abilities and morphological characteristics of female fourth-grade high-schoolers in Zagreb. A total sample of 220 high-schoolers aged 16-18 years were divided into two groups: experimental group of 115 students attending the program composed of dance structures and aerobics, and control group of 105 students attending classic program of physical education. A set of 3 morphological variables, 6 motor variables and one functional variable were applied in both groups on three occasions during an academic year (initial, transient and final measurements). Two-factor analysis of variance (MANOVA repeated measure design) showed the experimental program to significantly influence the development of coordination/agility and specific rhythm coordination, functional aerobic ability, repetitive and explosive strength and flexibility, along with significant reduction of overweight and adipose tissue. Study results clearly indicate that the existing programs of physical education should be revised and replaced by more appropriate ones.

The Use of Cattell's Profile Similarity Coefficient in the Classification of Football Athletes.

ERIC Educational Resources Information Center

Evans, Virden; Johnson, DeWayne

Using Cattell's Profile Similarity Coefficient, 154 high school football players from 21 different public high schools were classified as being successful or unsuccessful. Seventeen physical and motor ability variables relating to athletic ability were administered to the football players. The variables included: (1) standard height; (2) body…

Movement Activity Determination with Health-related Variables of University Students in Kosice.

PubMed

Bakalár, Peter; Zvonar, Martin; Sedlacek, Jaromir; Lenkova, Rut; Sagat, Peter; Vojtasko, Lubos; Liptakova, Erika; Barcalova, Miroslava

2018-06-01

There is currently a strong scientific evidence about the negative health consequences of physical inactivity. One of the potential tools for promoting physical activity at the institutional level of the Ecological model is to create conditions and settings that would enable pupils, students and employees engage in some form of physical activity. However, physical activities as a subject are being eliminated from the study programs at Slovak universities. The purpose of the study was to find current evidence about the level of structured physical activity and health-related variables in university students in Košice. The sample consisted of 1,993 or, more precisely, 1,398 students who attended two universities in Košice. To collect data, students completed a questionnaire and were tested for body height, body weight, circumferential measures and percentage body fat. The university students did not sufficiently engage in a structured physical activity. A large number of students had either low or high values of percentage body fat and BMI and high WHR values. Our findings have shown that the research into physical activity of university students should receive more attention.

Gender Differences in High School Students' Interests in Physics

ERIC Educational Resources Information Center

Baran, Medine

2016-01-01

The aim of this research was to determine the interests of high school students in Physics and variable of how the influential factors on their interests depending on gender. The research sample included 154 (F:78 M:76) high school students. A structured interview form was used as the data collection tool in the study. The research data were…

Importance of physical and hydraulic characteristics to unionid mussels: A retrospective analysis in a reach of large river

USGS Publications Warehouse

Zigler, S.J.; Newton, T.J.; Steuer, J.J.; Bartsch, M.R.; Sauer, J.S.

2008-01-01

Interest in understanding physical and hydraulic factors that might drive distribution and abundance of freshwater mussels has been increasing due to their decline throughout North America. We assessed whether the spatial distribution of unionid mussels could be predicted from physical and hydraulic variables in a reach of the Upper Mississippi River. Classification and regression tree (CART) models were constructed using mussel data compiled from various sources and explanatory variables derived from GIS coverages. Prediction success of CART models for presence-absence of mussels ranged from 71 to 76% across three gears (brail, sled-dredge, and dive-quadrat) and 51% of the deviance in abundance. Models were largely driven by shear stress and substrate stability variables, but interactions with simple physical variables, especially slope, were also important. Geospatial models, which were based on tree model results, predicted few mussels in poorly connected backwater areas (e.g., floodplain lakes) and the navigation channel, whereas main channel border areas with high geomorphic complexity (e.g., river bends, islands, side channel entrances) and small side channels were typically favorable to mussels. Moreover, bootstrap aggregation of discharge-specific regression tree models of dive-quadrat data indicated that variables measured at low discharge were about 25% more predictive (PMSE = 14.8) than variables measured at median discharge (PMSE = 20.4) with high discharge (PMSE = 17.1) variables intermediate. This result suggests that episodic events such as droughts and floods were important in structuring mussel distributions. Although the substantial mussel and ancillary data in our study reach is unusual, our approach to develop exploratory statistical and geospatial models should be useful even when data are more limited. ?? 2007 Springer Science+Business Media B.V.

Sensitivity to Verbally and Physically Harassing Behaviors and Reported Incidents in Junior High/Middle School Students.

ERIC Educational Resources Information Center

Turner, Penelope B.

This thesis investigates the sensitivity of junior high/middle school students to statements depicting verbal and physical sexual harassment. The independent variables that were investigated included gender, grade level, age, size of district, grades received, participation in sports, birth order, developmental level, and self-esteem. Students…

Upper and lower bounds of ground-motion variabilities: implication for source properties

NASA Astrophysics Data System (ADS)

Cotton, Fabrice; Reddy-Kotha, Sreeram; Bora, Sanjay; Bindi, Dino

2017-04-01

One of the key challenges of seismology is to be able to analyse the physical factors that control earthquakes and ground-motion variabilities. Such analysis is particularly important to calibrate physics-based simulations and seismic hazard estimations at high frequencies. Within the framework of the development of ground-motion prediction equation (GMPE) developments, ground-motions residuals (differences between recorded ground motions and the values predicted by a GMPE) are computed. The exponential growth of seismological near-source records and modern GMPE analysis technics allow to partition these residuals into between- and a within-event components. In particular, the between-event term quantifies all those repeatable source effects (e.g. related to stress-drop or kappa-source variability) which have not been accounted by the magnitude-dependent term of the model. In this presentation, we first discuss the between-event variabilities computed both in the Fourier and Response Spectra domains, using recent high-quality global accelerometric datasets (e.g. NGA-west2, Resorce, Kiknet). These analysis lead to the assessment of upper bounds for the ground-motion variability. Then, we compare these upper bounds with lower bounds estimated by analysing seismic sequences which occurred on specific fault systems (e.g., located in Central Italy or in Japan). We show that the lower bounds of between-event variabilities are surprisingly large which indicates a large variability of earthquake dynamic properties even within the same fault system. Finally, these upper and lower bounds of ground-shaking variability are discussed in term of variability of earthquake physical properties (e.g., stress-drop and kappa_source).

Inter-Annual and Shorter-Term Variability in Physical and Biological Characteristics Across Barrow Canyon in August - September 2005-2014

NASA Astrophysics Data System (ADS)

Ashjian, C. J.; Okkonen, S. R.; Campbell, R. G.; Alatalo, P.

2014-12-01

Late summer physical and biological conditions along a 37-km transect crossing Barrow Canyon have been described for the past ten years as part of an ongoing program, supported by multiple funding sources including the NSF AON, focusing on inter-annual variability and the formation of a bowhead whale feeding hotspot near Barrow. These repeated transects (at least two per year, separated in time by days-weeks) provide an opportunity to assess the inter-annual and shorter term (days-weeks) changes in hydrographic structure, ocean temperature, current velocity and transport, chlorophyll fluorescence, nutrients, and micro- and mesozooplankton community composition and abundance. Inter-annual variability in all properties was high and was associated with larger scale, meteorological forcing. Shorter-term variability could also be high but was strongly influenced by changes in local wind forcing. The sustained sampling at this location provided critical measures of inter-annual variability that should permit detection of longer-term trends that are associated with ongoing climate change.

Genetic variability in krill.

PubMed Central

Valentine, J W; Ayala, F J

1976-01-01

We have estimated genetic variability by gel electrophoresis in three species of krill, genus Euphausia (Arthropoda: Crustacea). Genetic variability is low where trophic resources are most seasonal, and high where trophic resources are most stable. Simlar trends have been found in benthic marine invertebrates. The observed trends of genetic variability do not correlate with trends in the stability of physical environment parameters. Images PMID:1061166

Presenteeism, stress resilience, and physical activity in older manual workers: a person-centred analysis.

PubMed

Thogersen-Ntoumani, Cecilie; Black, Julie; Lindwall, Magnus; Whittaker, Anna; Balanos, George M

2017-12-01

This study used a person-centred approach to explore typologies of older manual workers based on presenteeism, stress resilience, and physical activity. Older manual workers ( n  = 217; 69.1% male; age range 50-77; M age = 57.11 years; SD = 5.62) from a range of UK-based organisations, representing different manual job roles, took part in the study. A cross-sectional survey design was used. Based on the three input variables: presenteeism, stress resilience and physical activity, four distinct profiles were identified on using Latent Profile Analysis. One group ('High sport/exercise and well-functioning'; 5.50%) engaged in high levels of sport/exercise and exhibited low levels of stress resilience and all types of presenteeism. Another profile ('Physically burdened'; 9.70%) reported high levels of work and leisure-time physical activity, low stress resilience, as well as high levels of presenteeism due to physical and time demands. A 'Moderately active and functioning' group (46.50%) exhibited moderate levels on all variables. Finally, the fourth profile ('Moderately active with high presenteeism'; 38.20%) reported engaging in moderate levels of physical activity and had relatively high levels of stress resilience, yet also high levels of presenteeism. The profiles differed on work affect and health perceptions largely in the expected directions. There were no differences between the profiles in socio-demographics. These results highlight complex within-person interactions between presenteeism, stress resilience, and physical activity in older manual workers. The identification of profiles of older manual workers who are at risk of poor health and functioning may inform targeted interventions to help retain them in the workforce for longer.

Predicting academic performance of medical students: the first three years.

PubMed

Höschl, C; Kozený, J

1997-06-01

The purpose of this exploratory study was to identify a cluster of variables that would most economically explain variations in the grade point averages of medical students during the first 3 years of study. Data were derived from a study of 92 students admitted to the 3rd Faculty of Medicine in 1992-1993 academic year and who were still in the medical school at the end of the sixth semester (third year). Stepwise regression analysis was used to build models for predicting log-transformed changes in grade point average after six semesters of study-at the end of the first, second, and third years. Predictor variables were chosen from four domains: 1) high school grade point averages in physics, mathematics, and the Czech language over 4 years of study, 2) results of admission tests in biology, chemistry, and physics, 3) admission committee's assessment of the applicant's ability to reproduce a text, motivation to study medicine, and social maturity, and 4) scores on the sentimentality and attachment scales of the Tridimensional Personality Questionnaire. The regression model, which included performance in high school physics, results of the admission test in physics, assessment of the applicant's motivation to study medicine, and attachment scale score, accounted for 32% of the change in grade point average over six semesters of study. The regression models using the first-, second-, and third-year grade point averages as the dependent variables showed slightly decreasing amounts of explained variance toward the end of the third year of study and within domains, changing the structure of predictor variables. The results suggest that variables chosen from the assessment domains of high school performance, written entrance examination, admission interview, and personality traits may be significant predictors of academic success during the first 3 years of medical study.

Predictors of student success in entry-level science courses

NASA Astrophysics Data System (ADS)

Singh, Mamta K.

Although the educational evaluation process is useful and valuable and is supported by the Higher Education Act, a strong research base for program evaluation of college entry-level science courses is still lacking. Studies in science disciplines such as, biology, chemistry, and physics have addressed various affective and demographic factors and their relationships to student achievement. However, the literature contains little information that specifically addresses student biology content knowledge skills (basics and higher order thinking skills) and identifies factors that affect students' success in entry-level college science courses. These gate-keeping courses require detailed evaluation if the goal of an institution is to increase students' performance and success in these courses. These factors are, in fact, a stepping stone for increasing the number of graduates in Science, Technology, Engineering, and Mathematics (STEM) majors. The present study measured students' biology content knowledge and investigated students' performance and success in college biology, chemistry, and physics entry-level courses. Seven variables---gender, ethnicity, high school Grade Point Average (GPA), high school science, college major, school financial aid support, and work hours were used as independent variables and course final performance as a dichotomous dependent variable. The sample comprised voluntary student participants in entry-level science courses. The study attempted to explore eight research questions. Content knowledge assessments, demographic information analysis, multiple regression analysis, and binary logistic regression analysis were used to address research questions. The results suggested that high school GPA was a consistently good predictor of students' performance and success in entry-level science courses. Additionally, high school chemistry was a significant predictor variable for student success in entry-level biology and chemistry courses. Similarly, students' performance and success in entry-level physics courses were influenced by high school physics. Finally, the study developed student success equation with high school GAP and high school chemistry as good predictors of students' success in entry-level science courses.

Adherence to physical activity in an unsupervised setting: Explanatory variables for high attrition rates among fitness center members.

PubMed

Sperandei, Sandro; Vieira, Marcelo C; Reis, Arianne C

2016-11-01

To evaluate the attrition rate of members of a fitness center in the city of Rio de Janeiro and the potential explanatory variables for the phenomenon. An exploratory, observational study using a retrospective longitudinal frame. The records of 5240 individuals, members of the fitness center between January-2005 and June-2014, were monitored for 12 months or until cancellation of membership, whichever occurred first. A Cox proportional hazard regression model was adjusted to identify variables associated to higher risk of 'abandonment' of activities. This study was approved by Southern Cross University's Human Research Ethics Committee (approval number: ECN-15-176). The general survival curve shows that 63% of new members will abandon activities before the third month, and less than 4% will remain for more than 12 months of continuous activity. The regression model showed that age, previous level of physical activity, initial body mass index and motivations related to weight loss, hypertrophy, health, and aesthetics are related to risk of abandonment. Combined, those variables represent an important difference in the probability to abandon the gym between individuals with the best and worse combination of variables. Even individuals presenting the best combination of variables still present a high risk of abandonment before completion of 12 months of fitness center membership. Findings can assist in the identification of high risk individuals and therefore help in the development of strategies to prevent abandonment of physical activity practice. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Understanding the variable effect of instructional innovations on student learning

NASA Astrophysics Data System (ADS)

Iverson, Heidi L.

2012-02-01

As a result of dissatisfaction with the traditional lecture-based model of education a large number of reform-oriented instructional innovations have been developed, enacted, and studied in undergraduate physics courses. While previous work has shown that the impact of instructional innovations on student learning has been overwhelmingly positive, it has also been highly variable. The purpose of this analysis is to investigate this variability. For this analysis, 79 published studies on undergraduate physics instructional innovations were analyzed with respect to the types of innovations used and the methodological characteristics of the studies themselves. The findings of this analysis have indicated that nearly half of the variability in effect size can be accounted for by study design characteristics rather than by the characteristics of the innovations used. However, a subsequent analysis illustrated that one specific innovation, Workshop/Studio Physics, appears to be particularly effective within the observed sample of studies.

Habitual physical activity and plasma metabolomics patterns distinguish individuals with low- versus high-weight loss during controlled energy restriction

USDA-ARS?s Scientific Manuscript database

Weight loss (WL) induced by energy restriction is highly variable even in controlled clinical trials. An integrative analysis of the plasma metabolome coupled to traditional clinical variables may reveal a WL “responder” phenotype. Therfore, we predicted WL in overweight and obese individuals on a...

Habitual physical activity and plasma metabolomic patterns distinguish individuals with low vs. high weight loss during controlled energy restriction

USDA-ARS?s Scientific Manuscript database

Weight loss (WL) induced by energy restriction is highly variable even in controlled clinical trials. An integrative analysis of the plasma metabolome coupled to traditional clinical variables may reveal a WL “responder” phenotype. Therfore, we predicted WL in overweight and obese individuals on a...

Predictors of emotional and physical dating violence in a sample of serious juvenile offenders.

PubMed

Sweeten, Gary; Larson, Matthew; Piquero, Alex R

2016-10-01

We estimate group-based dating violence trajectories and identify the adolescent risk factors that explain membership in each trajectory group. Using longitudinal data from the Pathways to Desistance Study, which follows a sample of 1354 serious juvenile offenders from Philadelphia, Pennsylvania and Phoenix, Arizona between mid-adolescence and early adulthood, we estimate group-based trajectory models of both emotional dating violence and physical dating violence over a span of five years in young adulthood. We then estimate multinomial logistic regression models to identify theoretically motivated risk factors that predict membership in these groups. We identified three developmental patterns of emotional dating violence: none (33%), low-level (59%) and high-level decreasing (8%). The best-fitting model for physical dating violence also had three groups: none (73%), low-level (24%) and high-level (3%). Race/ethnicity, family and psychosocial variables were among the strongest predictors of both emotional and physical dating violence. In addition, delinquency history variables predicted emotional dating violence and relationship variables predicted physical dating violence. Dating violence is quite prevalent in young adulthood among serious juvenile offenders. Numerous predictors distinguish between chronic dating violence perpetrators and other groups. These may suggest points of intervention for reducing future violence. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Psychological determinants of adolescent exercise adherence.

PubMed

Douthitt, V L

1994-01-01

The purpose of this study was to identify some psychological determinants of exercise adherence on which public school physical education programs may have an impact. Data were collected twice, once representing a structured physical education classroom setting (N = 132), and later representing an unstructured summer vacation exercise setting (N = 110). Male and female physical education students at a large suburban high school completed five questionnaires which represented four psychological variables (self-motivation, perceived control, personality/sport congruence, and perceived self-competency), and one physical activity variable (exercise adherence) in both of the two data-collection periods. The results indicated that Perceived Romantic Appeal was predictive of male exercise adherence while Perceived Athletic Competency, Perceived Global Self-Worth, and Perceived Physical Appearance were predictive of female exercise adherence. None of the psychological predictor variables was significant for competitive subjects in either exercise setting, yet Perceived Romantic Appeal and Personality/Sport Congruence were predictive of noncompetitive subjects' exercise adherence in the structured and unstructured settings, respectively.

Holistic measurement of well-being: psychometric properties of the physical, mental and social well-being scale (PMSW-21) for adults.

PubMed

Supranowicz, Piotr; Paź, Małgorzata

2014-01-01

A holistic approach to health requires the development of tools that would allow to measure the inner world of individuals within its physical, mental and social dimensions. To create the Physical, Mental and Social Well-being scale (PMSW-21) that allows a holistic representation of various dimensions of well-being in such a way as they are perceived by the individuals and how affected their health. The study was conducted on the sample of 406 inhabitants of Warsaw involving in the Social Participation in Health Reform project. The PMSW-21 scale included: headache, tiredness, abdominal pain, palpitation, joint pain, backache, sleep disturbance (physical domain), anxiety, guiltiness, helplessness, hopelessness, sadness, self-dissatisfaction, hostility (mental domain), security, communicability, protection, loneliness, rejection, sociability and appreciation (social domain). The five criterial variables of health and seven of life experiences were adopted to assess the discriminative power of the PMSW-21 scale. The total well-being scale as well as its physical, mental and social domains showed high reliability (Cronbach a 0.81, 0.77, 0.90, 0.72, respectively). The analysis confirmed the construct validity. All the items stronger correlated with their own domain than with the others (ranges for physical: 0.41 - 0.55, mental: 0.49 - 0.80 and social: 0.31 - 0.50). The total scale demonstrate high sensitivity; it significantly differentiated almost all criterial variables. Physical domain showed high sensitivity for health as well as for negative life events variables, while the mental and social domains were more sensitive for life events. The analysis confirmed the usefulness of PMSW-21 scale for measure the holistic well-being. The reliability of the total scale and its domains, construct validity and sensitivity for health and life determinants were at acceptable level.

Symptom variability, affect and physical activity in ambulatory persons with multiple sclerosis: Understanding patterns and time-bound relationships.

PubMed

Kasser, Susan L; Goldstein, Amanda; Wood, Phillip K; Sibold, Jeremy

2017-04-01

Individuals with multiple sclerosis (MS) experience a clinical course that is highly variable with daily fluctuations in symptoms significantly affecting functional ability and quality of life. Yet, understanding how MS symptoms co-vary and associate with physical and psychological health is unclear. The purpose of the study was to explore variability patterns and time-bound relationships across symptoms, affect, and physical activity in individuals with MS. The study employed a multivariate, replicated, single-subject repeated-measures (MRSRM) design and involved four individuals with MS. Mood, fatigue, pain, balance confidence, and losses of balance were measured daily over 28 days by self-report. Physical activity was also measured daily over this same time period via accelerometry. Dynamic factor analysis (DFA) was used to determine the dimensionality and lagged relationships across the variables. Person-specific models revealed considerable time-dependent co-variation patterns as well as pattern variation across subjects. Results also offered insight into distinct variability structures at varying levels of disability. Modeling person-level variability may be beneficial for addressing the heterogeneity of experiences in individuals with MS and for understanding temporal and dynamic interrelationships among perceived symptoms, affect, and health outcomes in this group. Copyright © 2016 Elsevier Inc. All rights reserved.

Identifying environmental, social, and psychological correlates of meeting the recommended physical activity levels for colon cancer prevention among Japanese adults.

PubMed

Ishii, Kaori; Shibata, Ai; Oka, Koichiro

2013-11-01

Although physical activity reduces the risk of diseases such as cancer, diabetes and cardiovascular disease, a large proportion of the population is not sufficiently physically active. Therefore, the present study examined the environmental, social, and psychological correlates for meeting the 2 recommended physical activity criteria: ≥420 min per week of at least moderate-intensity activity (MPA criterion) and ≥210 min per week of vigorous activity (VPA criterion) for colon cancer prevention among Japanese adults. Cross-sectional study. The sample included 2000 Japanese adults aged 20-79 years. An Internet-based survey was used to assess seven sociodemographic variables (e.g., education level, employment status), environmental variables (home fitness equipment, access to facilities, neighborhood safety, aesthetic sensibilities, and frequency of observing others exercising, residential area), social variables (social support), psychological variables (self-efficacy, perceived positive (pros) and negative (cons) aspects of exercise), and physical activity. The adjusted odds of meeting each physical activity criterion by these variables were calculated. Overall, 22.3% of the study population met the criterion of MPA, and 7.3% met the criterion of VPA. Having high self-efficacy, fewer perceived cons, possessing home fitness equipment, reporting enjoyable scenery, and living in a rural area were significantly associated with meeting the recommended criteria. Participants who met the 2 activity recommendations differed by self-efficacy, cons, possession of home fitness equipment, reporting of enjoyable scenery, and residential area. These findings imply that strategies to promote more intense physical activities specifically in terms of these variables may be necessary for colon cancer prevention. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Family-related predictors of body weight and weight-related behaviours among children and adolescents: a systematic umbrella review.

PubMed

Cislak, A; Safron, M; Pratt, M; Gaspar, T; Luszczynska, A

2012-05-01

This umbrella review analysed the relationships between family variables and child/adolescent body weight, diet and physical activity. In line with theories of health behaviour change, it was assumed that behaviour-specific family variables (i.e. beliefs, perceptions and practices referring to food intake or physical activity) would have stronger support than more general family variables (i.e. socio-economic status or general parental practices). Data obtained from 18 systematic reviews (examining 375 quantitative studies) were analysed. Reviews of experimental trials generally supported the effectiveness of reward/positive reinforcement parental strategies, parental involvement in treatment or prevention programmes, and cognitive-behavioural treatment in reducing child/adolescent body mass and/or obesity. Results across reviews of correlational studies indicated that healthy nutrition of children/adolescents was related to only one parental practice (parental monitoring), but was associated with several behaviour-specific family variables (e.g. a lack of restrictive control over food choices, high intake of healthy foods and low intake of unhealthy foods by parents and siblings, low pressure to consume foods). With regard to adolescent physical activity, stronger support was also found for behaviour-specific variables (e.g. physical activity of siblings), and for certain socio-economic variables (e.g. parental education). Child and adolescent obesity prevention programmes should account for behaviour-specific family variables. © 2011 Blackwell Publishing Ltd.

[Resilience in caregivers of patients with dementia: A preliminary study].

PubMed

Fernández-Lansac, Violeta; Crespo López, María; Cáceres, Rebeca; Rodríguez-Poyo, María

2012-01-01

Caring for a relative with dementia often has negative effects on the caregiver's physical and psychological health. However, many caregivers successfully cope with the stress factors arising from care, and even have uplifts during their experience, showing high resilience levels. This study presents a preliminary analysis of resilience in caregivers of patients with dementia, exploring its relationship with different variables. Resilience was assessed (by CD-RISC) in 53 family caregivers of patients with dementia. Resilience was correlated to the following variables: caregiving context, stressors (e.g., cognitive impairment), appraisals (e.g., burden), moderators (e.g., personality traits and resources), and caregiving consequences (physical and psychological health). The participants showed moderate scores on resilience. Resilience was associated with poor emotional and physical status (significant inverse correlations with anxiety, depression, psycho-active drug use, health habits…). High resilience scores were significantly correlated to burden, neuroticism and extraversion, self-efficacy, self-esteem and less use of emotion focused coping strategies. Higher resilience relates to a good emotional and physical status in caregivers. Moreover, resilience is more associated with caregiver variables (e.g., appraisal and coping with care, personality features), than to situational variables. The data highlight the strengthening of these types of appraisal and coping as a way to improve caregivers' resilience and, consequently, their health. Copyright © 2011 SEGG. Published by Elsevier Espana. All rights reserved.

Fundamental movement skill performance of preschool children in relation to family context.

PubMed

Cools, Wouter; De Martelaer, Kristine; Samaey, Christiane; Andries, Caroline

2011-04-01

Evidence suggests the development of fundamental movement skill (FMS) is a key factor in promoting long-term physical activity. Low levels of activity among preschool children and the relationship between physical activity and the development of fundamental movement skills underline the need to determine the factors associated with children's development of such skills. As parents play an important role in the socialization process, the aim of this study was to examine correlates of family and neighbourhood characteristics as well as parental behaviour and beliefs on FMS performance in 4- to 6-year-old preschool children. Relationships between preschool children's FMS performance and family contextual variables were examined within a sample of 846 preschool children. Results identified positive associations of FMS performance with parental education, father's physical activity, transport to school by bicycle, and the high value placed by parents high on sport-specific aspects of children's physical activity. Variables negatively associated with preschool children's FMS performance included father-child interaction in TV-viewing and reading books, the high importance placed by parents on winning and performance in children's physical activity. Furthermore, the ambiguity of associations between FMS performance and parental beliefs underlined its complexity.

Is work engagement related to work ability beyond working conditions and lifestyle factors?

PubMed

Airila, Auli; Hakanen, Jari; Punakallio, Anne; Lusa, Sirpa; Luukkonen, Ritva

2012-11-01

To examine the associations of age, lifestyle and work-related factors, and particularly work engagement with the work ability index (WAI) and its sub-dimensions. Step-wise regression analysis with a sample of Finnish firefighters (n = 403) was used. The outcome variables were the WAI and its six sub-dimensions. The independent variables consisted of age, lifestyle variables (alcohol consumption, BMI, smoking, physical exercise, and sleep problems), working conditions (job demands, physical workload, supervisory relations, and task resources), and work engagement. The outcome variables and all the variables related to lifestyle, working conditions, and work engagement were measured in 2009. Work ability at baseline 10 years earlier was adjusted for in the models. Work engagement, age, physical exercise, sleep problems, and physical workload were associated with the WAI. All independent variables, except BMI and alcohol consumption, were associated with at least one sub-dimension of the WAI after controlling the baseline WAI. Lifestyle variables, working conditions, and work engagement were more strongly related to the subjective WAI sub-dimensions than to the two more objective WAI sub-dimensions. Work engagement was significantly associated with work ability even after adjusting for various factors, indicating its importance in promoting work ability. Other key factors for good work ability were frequent exercise, good sleep, non-smoking, low job demands, low physical workload, and high task resources. More specifically, this study suggests that in maintaining work ability, it is valuable not only to promote lifestyle factors or working conditions, but also to enhance employees' positive state of work engagement.

The value of crossdating to retain high-frequency variability, climate signals, and extreme events in environmental proxies

Treesearch

Bryan A. Black; Daniel Griffin; Peter van der Sleen; Alan D. Wanamaker; James H. Speer; David C. Frank; David W. Stahle; Neil Pederson; Carolyn A. Copenheaver; Valerie Trouet; Shelly Griffin; Bronwyn M. Gillanders

2016-01-01

High-resolution biogenic and geologic proxies in which one increment or layer is formed per year are crucial to describing natural ranges of environmental variability in Earth's physical and biological systems. However, dating controls are necessary to ensure temporal precision and accuracy; simple counts cannot ensure that all layers are placed correctly in time...

Higher screen time is associated with overweight, poor dietary habits and physical inactivity in Brazilian adolescents, mainly among girls.

PubMed

Christofaro, Diego Giulliano Destro; De Andrade, Selma Maffei; Mesas, Arthur Eumann; Fernandes, Rômulo Araújo; Farias Júnior, José Cazuza

2016-01-01

To analyse the associations between high screen time and overweight, poor dietary habits and physical activity in adolescents according to sex. The study comprised 515 boys and 716 girls aged 14-17 years from Londrina, Brazil. Nutritional status (normal weight or overweight/obese) was assessed by calculating the body mass index. Eating habits and time spent in physical activity were reported using a questionnaire. The measurement of screen time considered the time spent watching television, using a computer and playing video games during a normal week. Associations between high screen time and dependent variables (nutritional status, eating habits and physical activity levels) were assessed by binary logistic regression, adjusted for sociodemographic and lifestyle variables. Most adolescents (93.8% of boys and 87.2% of girls) spent more than 2 hours per day in screen-time activities. After adjustments, an increasing trend in the prevalence of overweight and physical inactivity with increasing time spent on screen activities was observed for both sexes. Screen times of >4 hours/day compared with <2 hours/day were associated with physical inactivity, low consumption of vegetables and high consumption of sweets only in girls and the consumption of soft drinks in both sexes. The frequency of overweight and physical inactivity increased with increasing screen time in a trending manner and independently of the main confounders. The relationship between high screen time and poor eating habits was particularly relevant for adolescent girls.

The Influence of Friendships and Friendship-Making Ability in Physical Activity Participation in Chiang Mai, Thailand High School Students

ERIC Educational Resources Information Center

Page, Randy M.; Taylor, Jerry; Suwanteerangkul, Jiraporn; Novilla, Lelinneth M.

2005-01-01

Unfortunately, the influence of friendships is a neglected area of investigation in studies of youth physical activity. This study investigated the degree to which three friendship variables (ability to make friends, level of involvement with friends, perceived friends' involvement in exercise/physical activity) was associated with physical…

Analysis of Self-Esteem Levels of Students in Physical Education and Sports High School

ERIC Educational Resources Information Center

çakoyun, Fahri Ak

2018-01-01

The purpose of this study is to examine the self-esteem levels of the students at Balikesir University Physical Education and Sports High School according to the variables such; gender, age, body-mass index (BMI), education department, class, sporting situation and sport branch (individual sport-team sport). While the universe of the study has…

Students' Evaluation of Professional Personality Competencies of Physical Education Teachers Working in High Schools

ERIC Educational Resources Information Center

Demir, Erdal

2015-01-01

The purpose of the study is to examine the relationship between professional personality competencies of physical education teachers working in high schools and gender, school type, and class variables of students. The study was organised according to the screening model. The study was carried out in a total of 17 schools, 16 state and one…

Patterns in the Physical, Chemical, and Biological Composition of Icelandic Lakes and the Dominant Factors Controlling Variability Across Watersheds

NASA Astrophysics Data System (ADS)

Greco, A.; Strock, K.; Edwards, B. R.

2017-12-01

Fourteen lakes were sampled in the southern and western area of Iceland in June of 2017. The southern systems, within the Eastern Volcanic Zone, have minimal soil development and active volcanoes that produce ash input to lakes. Lakes in the Western Volcanic Zone were more diverse and located in older bedrock with more extensively weathered soil. Physical variables (temperature, oxygen concentration, and water clarity), chemical variables (pH, conductivity, dissolved and total nitrogen and phosphorus concentrations, and dissolved organic carbon concentration), and biological variables (algal biomass) were compared across the lakes sampled in these geographic regions. There was a large range in lake characteristics, including five to eighteen times higher algal biomass in the southern systems that experience active ash input to lakes. The lakes located in the Eastern Volcanic Zone also had higher conductivity and lower pH, especially in systems receiving substantial geothermal input. These results were analyzed in the context of more extensive lake sampling efforts across Iceland (46 lakes) to determine defining characteristics of lakes in each region and to identify variables that drive heterogeneous patterns in physical, chemical, and biological lake features within each region. Coastal systems, characterized by high conductivity, and glacially-fed systems, characterized by high iron concentrations, were unique from lakes in all other regions. Clustering and principal component analyses revealed that lake type (plateau, valley, spring-fed, and direct-runoff) was not the primary factor explaining variability in lake chemistry outside of the coastal and glacial lake types. Instead, lakes differentiated along a gradient of iron concentration and total nitrogen concentration. The physical and chemical properties of subarctic lakes are especially susceptible to both natural and human-induced environmental impacts. However, relatively little is known about the contemporary physical and chemical properties of Icelandic lakes, despite their abundance and importance as freshwater resources. Here we report an analysis of the physical, chemical, and biological characteristics of a set of subarctic lakes and use spatial Information to infer controls on lake heterogeneity within and across regions.

Spatial heterogeneity of within-stream methane concentrations

NASA Astrophysics Data System (ADS)

Crawford, John T.; Loken, Luke C.; West, William E.; Crary, Benjamin; Spawn, Seth A.; Gubbins, Nicholas; Jones, Stuart E.; Striegl, Robert G.; Stanley, Emily H.

2017-05-01

Streams, rivers, and other freshwater features may be significant sources of CH4 to the atmosphere. However, high spatial and temporal variabilities hinder our ability to understand the underlying processes of CH4 production and delivery to streams and also challenge the use of scaling approaches across large areas. We studied a stream having high geomorphic variability to assess the underlying scale of CH4 spatial variability and to examine whether the physical structure of a stream can explain the variation in surface CH4. A combination of high-resolution CH4 mapping, a survey of groundwater CH4 concentrations, quantitative analysis of methanogen DNA, and sediment CH4 production potentials illustrates the spatial and geomorphic controls on CH4 emissions to the atmosphere. We observed significant spatial clustering with high CH4 concentrations in organic-rich stream reaches and lake transitions. These sites were also enriched in the methane-producing mcrA gene and had highest CH4 production rates in the laboratory. In contrast, mineral-rich reaches had significantly lower concentrations and had lesser abundances of mcrA. Strong relationships between CH4 and the physical structure of this aquatic system, along with high spatial variability, suggest that future investigations will benefit from viewing streams as landscapes, as opposed to ecosystems simply embedded in larger terrestrial mosaics. In light of such high spatial variability, we recommend that future workers evaluate stream networks first by using similar spatial tools in order to build effective sampling programs.

Optical coatings of variable refractive index and high laser-resistance from physical-vapor-deposited perfluorinated amorphous polymer

DOEpatents

Chow, Robert; Loomis, Gary E.; Thomas, Ian M.

1999-01-01

Variable index optical single-layers, optical multilayer, and laser-resistant coatings were made from a perfluorinated amorphous polymer material by physical vapor deposition. This was accomplished by physically vapor depositing a polymer material, such as bulk Teflon AF2400, for example, to form thin layers that have a very low refractive index (.about.1.10-1.31) and are highly transparent from the ultra-violet through the near infrared regime, and maintain the low refractive index of the bulk material. The refractive index can be varied by simply varying one process parameter, either the deposition rate or the substrate temperature. The thus forming coatings may be utilized in anti-reflectors and graded anti-reflection coatings, as well as in optical layers for laser-resistant coatings at optical wavelengths of less than about 2000 nm.

Peers and teachers as sources of relatedness perceptions, motivation, and affective responses in physical education.

PubMed

Cox, Anne; Duncheon, Nicole; McDavid, Lindley

2009-12-01

Research has demonstrated the importance of relatedness perceptions to self-determined motivation in physical education. Therefore, studies have begun to examine the social factors contributing to feelings of relatedness. The purpose of this study was to examine teacher (perceived emotional support) and peer (acceptance, friendship quality) relationship variables to feelings of relatedness, motivation, and affective responses in junior high physical education students (N = 411). Results revealed that perceived relatedness mediated the relationship between variables and self-determined motivation and related directly to the amount of enjoyment and worry students experienced. These findings demonstrate that relationships with both teachers and peers are important for students' relatedness perceptions, motivation, enjoyment, and worry in physical education.

Factors influencing physical and technical variability in the English Premier League.

PubMed

Bush, Michael D; Archer, David T; Hogg, Robert; Bradley, Paul S

2015-10-01

To investigate match-to-match variability of physical and technical performances in English Premier League players and quantify the influence of positional and contextual factors. Match data (N = 451) were collected using a multicamera computerized tracking system across multiple seasons (2005-06 to 2012-13). The coefficient of variation (CV) was calculated from match to match for physical and technical performances in selected positions across different match contexts (location, standard, and result). Wide midfielders demonstrated the greatest CVs for total distance (4.9% ± 5.9%) and central midfielders the smallest (3.6% ± 2.0%); nevertheless, all positions exhibited CVs <5% (P > .05, effect size [ES] 0.1-0.3). Central defenders demonstrated the greatest CVs and wide midfielders the lowest for both high-intensity running (20.2% ± 8.8% and 13.7% ± 7.7%, P < .05, ES 0.4-0.8) and sprint distance (32.3% ± 13.8% and 22.6% ± 11.2%, P < .05, ES 0.5-0.8). Technical indicators such as tackles (83.7% ± 42.3%), possessions won (47.2% ± 27.9%), and interceptions (59.1% ± 37.3%) illustrated substantial variability for attackers compared with all other positions (P < .05, ES 0.4-1.1). Central defenders demonstrated large variability for the number of times tackled per match (144.9% ± 58.3%) and passes attempted and received compared with other positions (39.2% ± 17.5% and 46.9% ± 20.2%, P < .001, ES 0.6-1.8). Contextual factors had limited impact on the variability of physical and technical parameters. The data demonstrate that technical parameters varied more from match to match than physical parameters. Defensive players (fullbacks and central defenders) displayed higher CVs for offensive technical variables, while attacking players (attackers and wide midfielders) exhibited higher CVs for defensive technical variables. Physical and technical performances are variable per se regardless of context.

Cross-national validation of prognostic models predicting sickness absence and the added value of work environment variables.

PubMed

Roelen, Corné A M; Stapelfeldt, Christina M; Heymans, Martijn W; van Rhenen, Willem; Labriola, Merete; Nielsen, Claus V; Bültmann, Ute; Jensen, Chris

2015-06-01

To validate Dutch prognostic models including age, self-rated health and prior sickness absence (SA) for ability to predict high SA in Danish eldercare. The added value of work environment variables to the models' risk discrimination was also investigated. 2,562 municipal eldercare workers (95% women) participated in the Working in Eldercare Survey. Predictor variables were measured by questionnaire at baseline in 2005. Prognostic models were validated for predictions of high (≥30) SA days and high (≥3) SA episodes retrieved from employer records during 1-year follow-up. The accuracy of predictions was assessed by calibration graphs and the ability of the models to discriminate between high- and low-risk workers was investigated by ROC-analysis. The added value of work environment variables was measured with Integrated Discrimination Improvement (IDI). 1,930 workers had complete data for analysis. The models underestimated the risk of high SA in eldercare workers and the SA episodes model had to be re-calibrated to the Danish data. Discrimination was practically useful for the re-calibrated SA episodes model, but not the SA days model. Physical workload improved the SA days model (IDI = 0.40; 95% CI 0.19-0.60) and psychosocial work factors, particularly the quality of leadership (IDI = 0.70; 95% CI 053-0.86) improved the SA episodes model. The prognostic model predicting high SA days showed poor performance even after physical workload was added. The prognostic model predicting high SA episodes could be used to identify high-risk workers, especially when psychosocial work factors are added as predictor variables.

Contrasting controls of pH climatology in an open coast versus urban fjord estuary

EPA Science Inventory

Interactions of physical, chemical, and biological processes in the coastal zone can result in a highly variable carbonate chemistry regime. This characteristic variability in coastal areas has garnered renewed interest within the context of ocean acidification, yet the relative...

Variables that Correlate with Faculty Use of Research-Based Instructional Strategies

NASA Astrophysics Data System (ADS)

Henderson, Charles; Dancy, Melissa H.; Niewiadomska-Bugaj, Magdalena

2010-10-01

During the Fall of 2008 a web survey, designed to collect information about pedagogical knowledge and practices, was completed by a representative sample of 722 physics faculty across the United States (a 50.3% response rate). This paper examines how 20 predictor variables correlate with faculty knowledge about and use of research-based instructional strategies (RBIS). Profiles were developed for each of four faculty levels of knowledge about and use of RBIS. Logistic regression analysis was used to identify a subset of the variables that could predict group membership. Five significant predictor variables were identified. High levels of knowledge and use of RBIS were associated with the following characteristics: attendee of the physics and astronomy new faculty workshop, attendee of at least one talk or workshop related to teaching in the last two years, satisfaction with meeting instructional goals, regular reader of one or more journals related to teaching, and being female. High research productivity and large class sizes were not found to be barriers to use of at least some RBIS.

Nonlinear intrinsic variables and state reconstruction in multiscale simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dsilva, Carmeline J., E-mail: cdsilva@princeton.edu; Talmon, Ronen, E-mail: ronen.talmon@yale.edu; Coifman, Ronald R., E-mail: coifman@math.yale.edu

2013-11-14

Finding informative low-dimensional descriptions of high-dimensional simulation data (like the ones arising in molecular dynamics or kinetic Monte Carlo simulations of physical and chemical processes) is crucial to understanding physical phenomena, and can also dramatically assist in accelerating the simulations themselves. In this paper, we discuss and illustrate the use of nonlinear intrinsic variables (NIV) in the mining of high-dimensional multiscale simulation data. In particular, we focus on the way NIV allows us to functionally merge different simulation ensembles, and different partial observations of these ensembles, as well as to infer variables not explicitly measured. The approach relies on certainmore » simple features of the underlying process variability to filter out measurement noise and systematically recover a unique reference coordinate frame. We illustrate the approach through two distinct sets of atomistic simulations: a stochastic simulation of an enzyme reaction network exhibiting both fast and slow time scales, and a molecular dynamics simulation of alanine dipeptide in explicit water.« less

Nonlinear intrinsic variables and state reconstruction in multiscale simulations

NASA Astrophysics Data System (ADS)

Dsilva, Carmeline J.; Talmon, Ronen; Rabin, Neta; Coifman, Ronald R.; Kevrekidis, Ioannis G.

2013-11-01

Finding informative low-dimensional descriptions of high-dimensional simulation data (like the ones arising in molecular dynamics or kinetic Monte Carlo simulations of physical and chemical processes) is crucial to understanding physical phenomena, and can also dramatically assist in accelerating the simulations themselves. In this paper, we discuss and illustrate the use of nonlinear intrinsic variables (NIV) in the mining of high-dimensional multiscale simulation data. In particular, we focus on the way NIV allows us to functionally merge different simulation ensembles, and different partial observations of these ensembles, as well as to infer variables not explicitly measured. The approach relies on certain simple features of the underlying process variability to filter out measurement noise and systematically recover a unique reference coordinate frame. We illustrate the approach through two distinct sets of atomistic simulations: a stochastic simulation of an enzyme reaction network exhibiting both fast and slow time scales, and a molecular dynamics simulation of alanine dipeptide in explicit water.

Strength Training Following Hematopoietic Stem Cell Transplantation

PubMed Central

Hacker, Eileen Danaher; Larson, Janet; Kujath, Amber; Peace, David; Rondelli, Damiano; Gaston, Lisa

2010-01-01

Background Patients receiving high-dose chemotherapy and hematopoietic stem cell transplantation (HSCT) experience considerable reductions in physical activity and deterioration of their health status. Objective The purpose of this pilot study was to test the effects of strength training compared to usual activity on physical activity, muscle strength, fatigue, health status perceptions, and quality of life following HSCT. Interventions/Methods Nineteen subjects were randomized to the exercise or control group. Moderate intensity strength training began following discharge from the hospital. Dependent variables included physical activity, muscle strength, fatigue, health status perceptions and quality of life. Variables were measured prior to admission to the hospital for HSCT, day 8 following HSCT, and six weeks following discharge from the hospital. Results Significant time effects were noted for many variables with anticipated declines in physical activity, muscle strength, fatigue, and health status perceptions immediately after HSCT with subsequent improvements six weeks following hospital discharge. One group effect was noted with subjects in the exercise group reporting less fatigue than subjects in the control group. Although no significant interactions were detected, the trends suggest that the exercise group may be more physically active following the intervention compared to the usual activity group. Conclusions This study demonstrates the potential positive effects of strength training on physical activity, fatigue, and quality of life in people receiving high-dose chemotherapy and HSCT. Implications for Practice Preliminary evidence is provided for using strength training to enhance early recovery following HSCT. Elastic resistance bands are easy to use and relatively inexpensive. PMID:21116175

The influence of the guided constructivist instructional model on attitudes toward secondary-level physics

NASA Astrophysics Data System (ADS)

Dallal, Kamel Salim

The effect of guided constructivism (bridging analogies) and expository instructional methods on the attitudes of students toward physics was investigated. A nonrandomize nonequivalent pretest-posttest control group quasi- experimental design was employed. The sample consisted of 127 eleventh-grade and twelfth-grade students from five selected classes from two private high schools in Beirut, Lebanon. Two intact classes were assigned to the control group and three classes to the experimental group. The experimental group was exposed to the bridging analogies instructional method, and the control group was taught using the traditional expository method. A Likert-type instrument, the Physics Attitude Index, was used to measure attitudes on four dimensions. The 40-item Physics Attitude Index (PAI) is a questionnaire using a five response scale. Performance in the assigned topics in physics, cognitive developmental levels, and gender were used as covariants and to examine interaction effects. The experimental groups had significantly higher means than the control groups on all criterion variables. A significant interaction was found between groups and performance levels in the following cases: (a) criterion variable of attitude toward physics; (b) views toward physics learning; and (c) enjoyment of physics. This result indicated that the low performing students among the experimental group had greater gain in attitude toward physics than the high performing students in same group. On the other hand, no interaction occurred between treatment groups and gender, which shows that in this study gender has no significant effect on attitude toward physics. Significant interactions between the treatment groups and cognitive levels were found on the criterion variable of beliefs about physics as a process of learning and enjoyment of physics. In both cases, the difference between the group means were widely different among students at the concrete and transitional levels, but narrowly different among students at the formal level.

Effects of physical activity at work and life-style on sleep in workers from an Amazonian Extractivist Reserve.

PubMed

Martins, Andressa Juliane; Vasconcelos, Suleima Pedroza; Skene, Debra Jean; Lowden, Arne; de Castro Moreno, Claudia Roberta

2016-01-01

Physical activity has been recommended as a strategy for improving sleep. Nevertheless, physical effort at work might not be not the ideal type of activity to promote sleep quality. The aim of this study was to evaluate the effects of type of job (low vs. high physical effort) and life-style on sleep of workers from an Amazonian Extractivist Reserve, Brazil. A cross-sectional study of 148 low physical activity (factory workers) and 340 high physical activity (rubber tappers) was conducted between September and November 2011. The workers filled out questionnaires collecting data on demographics (sex, age, occupation, marital status and children), health (reported morbidities, sleep disturbances, musculoskeletal pain and body mass index) and life-style (smoking, alcohol use and practice of leisure-time physical activity). Logistic regression models were applied with the presence of sleep disturbances as the primary outcome variable. The prevalence of sleep disturbances among factory workers and rubber tappers was 15.5% and 27.9%, respectively. The following independent variables of the analysis were selected based on a univariate model (p<0.20): sex, age, marital status, work type, smoking, morbidities and musculoskeletal pain. The predictors for sleep disturbances were type of job (high physical effort); sex (female); age (>40 years), and having musculoskeletal pain (≥5 symptoms). Rubber tapper work, owing to greater physical effort, pain and musculoskeletal fatigue, was associated with sleep disturbances. Being female and older than 40 years were also predictors of poor sleep. In short, these findings suggest that demanding physical exertion at work may not improve sleep quality.

Mechanism by which BMI influences leisure-time physical activity behavior.

PubMed

Godin, Gaston; Bélanger-Gravel, Ariane; Nolin, Bertrand

2008-06-01

The objective of this prospective study was to clarify the mechanism by which BMI influences leisure-time physical activity. This was achieved in accordance with the assumptions underlying the Theory of Planned Behavior (TPB), considered as one of the most useful theories to predict behavior adoption. At baseline, a sample of 1,530 respondents completed a short questionnaire to measure intention and perceived behavioral control (PBC), the two proximal determinants of behavior of TPB. Past behavior, sociodemographic variables, and weight and height were also assessed. The dependent variable, leisure-time physical activity was assessed 3 months later. Hierarchical multiple regression analyses revealed that BMI is a direct predictor of future leisure-time physical activity, not mediated by the variables of TPB. Additional hierarchical analyses indicated that BMI was not a moderator of the intention-behavior and PBC-behavior relationships. The results of this study suggest that high BMI is a significant negative determinant of leisure-time physical activity. This observation reinforces the importance of preventing weight gain as a health promotion strategy for avoiding a sedentary lifestyle.

Experience, gender, and performance: Connecting high school physics experience and gender differences to introductory college physics performance

NASA Astrophysics Data System (ADS)

Tai, Robert H.

Current science educational practice is coming under heavy criticism based on the dismaying results of the Third International Mathematics and Science Study of 1998, the latest in a series of large scale surveys; and from research showing the appallingly low representation of females in science-related fields. These critical evaluations serve to draw attention to science literacy in general and lack of persistence among females in particular, two issues that relate closely to the "preparation for future study" goal held by many high school science teachers. In other words, these teachers often seek to promote future success and to prevent future failure in their students' academic careers. This thesis studies the connection between the teaching practices recommended by reformers and researchers for high school teachers, and their students' subsequent college physics performance. The teaching practices studied were: laboratory experiences, class discussion experiences, content coverage, and reliance on textbooks. This study analyzed a survey of 1500 students from 16 different lecture-format college physics courses at 14 different universities. Using hierarchical linear modeling, this study accounted for course-level variables (Calculus-based/Non-calculus course type, professor's gender, and university selectivity). This study controlled for the student's parents education, high school science/mathematics achievement, high school calculus background, and racial background. In addition, the interactions between gender and both pedagogical/curricular and course-level variables were analyzed. The results indicated that teaching fewer topics in greater depth in high school physics appeared to be helpful to college physics students. An interaction between college course type and content coverage showed that students in Calculus-based physics reaped even greater benefits from a depth-oriented curriculum. Also students with fewer labs per month in high school physics appeared to perform better in college physics than did students with many more labs per month. The only significant interaction was between gender and Calculus-based/Non-calculus college course type. Females appeared to do better on average than their males counterparts in Non-calculus physics, but this trend is clearly reversed for Calculus-based physics. This is a disturbing result for educators who have worked to promote persistence among women in engineering and science research. Recommendations are included for high school physics teachers, students and their parents, and college physics instructors.

The Texas Youth Fitness Study: Looking at School Policies as They Relate to Physical Fitness and Academic Variables. Program Results Report

ERIC Educational Resources Information Center

Feiden, Karyn

2011-01-01

In partnership with three universities, the Cooper Institute, Dallas, completed the Texas Youth Fitness Study from 2008 to 2009. The study explored three key questions: (1) Is physical fitness associated with academic performance?; (2) Can physical education teachers collect high-quality information on student fitness?; and (3) Are school policies…

Variable Selection for Regression Models of Percentile Flows

NASA Astrophysics Data System (ADS)

Fouad, G.

2017-12-01

Percentile flows describe the flow magnitude equaled or exceeded for a given percent of time, and are widely used in water resource management. However, these statistics are normally unavailable since most basins are ungauged. Percentile flows of ungauged basins are often predicted using regression models based on readily observable basin characteristics, such as mean elevation. The number of these independent variables is too large to evaluate all possible models. A subset of models is typically evaluated using automatic procedures, like stepwise regression. This ignores a large variety of methods from the field of feature (variable) selection and physical understanding of percentile flows. A study of 918 basins in the United States was conducted to compare an automatic regression procedure to the following variable selection methods: (1) principal component analysis, (2) correlation analysis, (3) random forests, (4) genetic programming, (5) Bayesian networks, and (6) physical understanding. The automatic regression procedure only performed better than principal component analysis. Poor performance of the regression procedure was due to a commonly used filter for multicollinearity, which rejected the strongest models because they had cross-correlated independent variables. Multicollinearity did not decrease model performance in validation because of a representative set of calibration basins. Variable selection methods based strictly on predictive power (numbers 2-5 from above) performed similarly, likely indicating a limit to the predictive power of the variables. Similar performance was also reached using variables selected based on physical understanding, a finding that substantiates recent calls to emphasize physical understanding in modeling for predictions in ungauged basins. The strongest variables highlighted the importance of geology and land cover, whereas widely used topographic variables were the weakest predictors. Variables suffered from a high degree of multicollinearity, possibly illustrating the co-evolution of climatic and physiographic conditions. Given the ineffectiveness of many variables used here, future work should develop new variables that target specific processes associated with percentile flows.

Interaction between leptin and leisure-time physical activity and development of hypertension.

PubMed

Asferg, Camilla; Møgelvang, Rasmus; Flyvbjerg, Allan; Frystyk, Jan; Jensen, Jan S; Marott, Jacob L; Appleyard, Merete; Schnohr, Peter; Jensen, Gorm B; Jeppesen, J Rgen

2011-12-01

OBJECTIVE. The mechanisms by which overweight and physical inactivity lead to hypertension are complex. Leptin, an adipocyte-derived hormone, has been linked with hypertension. We wanted to investigate the relationship between leptin, physical activity and new-onset hypertension. METHODS. The study was a prospective cohort study of 744 women and 367 men, who were normotensive in the third Copenhagen City Heart Study (CCHS) examination, performed 1991−94. Based on questionnaire items, the participants were divided into two groups with low (n = 674) and high (n = 437) levels of leisure-time physical activity, respectively. RESULTS. Between the third and the fourth CCHS examination, performed 2001?03, 304 had developed hypertension, defined as systolic blood pressure (SBP) ≥140 mmHg or diastolic blood pressure (DBP) ≥90 mmHg or use of antihypertensive medication. In a logistic regression model, including age, sex, body mass index, SBP, DBP, level of physical activity and leptin, we found a significant interaction between leptin and level of physical activity with new-onset hypertension as outcome variable (p = 0.012). When we entered the interaction variables, effect of leptin with low level of physical activity and with high level of physical activity, respectively, in the original model, leptin predicted new-onset hypertension in participants with low level of physical activity [odds ratio (95% confidence interval): 1.16 (1.01−1.33) for one unit increase in log-transformed leptin levels, p = 0.038], but not in participants with high level of physical activity [0.88 (0.74−1.05), p = 0.15]. CONCLUSION. We found that leptin predicted new-onset hypertension but only in participants with low level of physical activity.

Newton in the Big Apple: Issues of equity in physics access and enrollment in New York City public high schools

NASA Astrophysics Data System (ADS)

Kelly, Angela Marian

High school physics is a gateway course for post-secondary study in science, medicine, and engineering, as well as an essential component in the formation of students' scientific literacy. However, physics is widely considered appropriate only for an academic elite. The existence of policies that restrict science opportunities for secondary students results in diminished outcomes in terms of scientific proficiency. Although the national trend in physics enrollment has shown an increase in recent years, the rate of participation is much lower for students in urban schools. This study examines the availability of physics in New York City, and whether access is related to organizational and school-level variables. The statistical distribution of physics students throughout the city is compiled and analyzed. High schools that successfully offer physics are compared with those that do not. Other factors are explored to determine their relationship to physics access, such as the presence of science magnet schools, the availability of Advanced Placement Physics and Non-Regents Physics, the science curricular sequence, and teacher certification. The results show that physics is not widely available to students in New York City, with 55% of high schools simply not offering the subject. Only 27% of schools with fewer than 600 students offer physics. The science magnet schools enroll a significant proportion of physics students when compared with larger, economically depressed neighborhood schools. The causes of these disparities are complex, and the implications serious for those students who do not have equal access to physics. The implications of these findings are important. By highlighting descriptive variables, as well as statistical evidence of systemic discrimination and inequities, urban districts may formulate effective models for the promotion of physics study. School policies and structures need to target better rates of physics participation among all students, regardless of socioeconomic status or race. The evidence presented here is a starting point for identifying the extent of inequities in order to develop long-term reform efforts to improve physics access for all.

Optical coatings of variable refractive index and high laser-resistance from physical-vapor-deposited perfluorinated amorphous polymer

DOEpatents

Chow, R.; Loomis, G.E.; Thomas, I.M.

1999-03-16

Variable index optical single-layers, optical multilayer, and laser-resistant coatings were made from a perfluorinated amorphous polymer material by physical vapor deposition. This was accomplished by physically vapor depositing a polymer material, such as bulk Teflon AF2400, for example, to form thin layers that have a very low refractive index (ca. 1.10--1.31) and are highly transparent from the ultra-violet through the near infrared regime, and maintain the low refractive index of the bulk material. The refractive index can be varied by simply varying one process parameter, either the deposition rate or the substrate temperature. The thus forming coatings may be utilized in anti-reflectors and graded anti-reflection coatings, as well as in optical layers for laser-resistant coatings at optical wavelengths of less than about 2000 nm. 2 figs.

Predicting physical activity and fruit and vegetable intake in adolescents: a test of the information, motivation, behavioral skills model.

PubMed

Kelly, Stephanie; Melnyk, Bernadette Mazurek; Belyea, Michael

2012-04-01

Most adolescents do not meet national recommendations regarding physical activity and/or the intake of fruits and vegetables. The purpose of this study was to explore whether variables in the information, motivation, behavioral skills (IMB) model of health promotion predicted physical activity and fruit and vegetable intake in 404 adolescents from 2 high schools in the Southwest United States using structural equation modeling (SEM). The SEM models included theoretical constructs, contextual variables, and moderators. The theoretical relationships in the IMB model were confirmed and were moderated by gender and race. Interventions that incorporate cognitive-behavioral skills building may be a key factor for promoting physical activity as well as fruit and vegetable intake in adolescents. Copyright © 2012 Wiley Periodicals, Inc.

Effects of same-sex versus coeducational physical education on the self-perceptions of middle and high school students.

PubMed

Lirgg, C D

1993-09-01

The purpose of this field experiment was to investigate the effects of attending either a coeducational or a same-sex physical education class on several self-perception variables. Middle and high school youth who had previously been in coeducational classes were assigned to either a same-sex or a new coeducational physical education class for a 10-lesson unit of basketball. Analyses were conducted at both the group and the individual levels. Self-perception variables examined included perceived self-confidence of learning basketball, perceived usefulness of basketball, and perceived gender-appropriateness of basketball. Results of hierarchical linear model group level analyses indicated that the variability in groups for self-confidence could be explained by grade, class type, and the interaction between gender and class type. At the individual level, multivariate results showed that, after the unit, males in coeducational classes were significantly more confident in their ability to learn basketball than males in same-sex classes. Also, males in same-sex classes decreased in confidence from pretreatment to posttreatment. Perceived usefulness of basketball emerged as the strongest predictor of self-confidence for learning basketball for both genders. In general, middle school students preferred same-sex classes, whereas high school students preferred coeducational classes.

Psychobiology and behavioral strategies. Physical activity, sport participation, and suicidal behavior: U.S. high school students.

PubMed

Brown, David R; Galuska, Deborah A; Zhang, Jian; Eaton, Danice K; Fulton, Janet E; Lowry, Richard; Maynard, L Michele

2007-12-01

To evaluate the associations of physical activity and sports team participation with suicidal behavior among U.S. high school students. Data were from the 2003 Youth Risk Behavior Survey (N = 10,530 respondents). Exposure variables included physical activity (inactive, insufficient, moderately intensive, regular vigorously intensive, and frequent vigorously intensive) and sports team participation. Outcome variables were suicide ideation (seriously considering and/or planning suicide) and suicide attempts. Hierarchical logistic regressions were run, controlling for age, race, smoking, alcohol use, drug use, geographic region, unhealthy weight-control practices, and body mass index/weight perceptions. Compared with inactive students or sports team nonparticipants, the odds of suicide ideation were lower among boys reporting frequent vigorous-intensity physical activity (adjusted odds ratio (AOR) = 0.48; 95% confidence interval (CI) = 0.29, 0.79) and sports team participation, respectively (AOR = 0.65; 95% CI = 0.48, 0.86). The odds of suicide attempts were also lower among frequently vigorously active boys (AOR = 0.44; 95% CI = 0.21, 0.96) and sports team participants (AOR = 0.61; 95% CI = 0.40, 0.93). The odds of suicide attempts were lower for regular vigorously active girls compared with inactive girls (AOR = 0.67; 95% CI = 0.45, 0.99) and sports team participants compared with nonparticipants (AOR = 0.73; 95% CI = 0.57, 0.94). Associations with one exposure variable generally weakened when adjustment was made for the other exposure variable, or for feeling sad and hopeless. The association of physical activity and sports team participation with suicide ideation and suicide attempts varied by sex. Further research is needed to clarify these different associations.

When is affect variability bad for health? The association between affect variability and immune response to the influenza vaccination.

PubMed

Jenkins, Brooke N; Hunter, John F; Cross, Marie P; Acevedo, Amanda M; Pressman, Sarah D

2018-01-01

This study addresses methodological and theoretical questions about the association between affect and physical health. Specifically, we examine the role of affect variability and its interaction with mean levels of affect to predict antibody (Ab) levels in response to an influenza vaccination. Participants (N=83) received the vaccination and completed daily diary measures of affect four times a day for 13days. At one and four months post-vaccination, blood was collected from the participants to assess Ab levels. Findings indicate that affect variability and its interaction with mean levels of affect predict an individual's immune response. Those high in mean positive affect (PA) who had more PA variability were more likely to have a lower Ab response in comparison to those who had high mean PA and less PA variability. Although it did not interact with mean negative affect (NA), NA variability on its own was associated with Ab response, whereby those with less NA variability mounted a more robust immune response. Affect variability is related to immune response to an influenza vaccination and, in some cases, interacts with mean levels of affect. These oscillations in affective experiences are critical to consider in order to unpack the intricacies of how affect influences health. These findings suggest that future researchers should consider the important role of affect variability on physical health-relevant outcomes as well as examine the moderating effect of mean affect levels. Copyright © 2017 Elsevier Inc. All rights reserved.

Independent Associations and Interactions of Perceived Neighborhood and Psychosocial Constructs on Adults' Physical Activity.

PubMed

Dwyer, Laura A; Patel, Minal; Nebeling, Linda C; Oh, April Y

2018-05-01

Neighborhood and psychosocial variables are related to physical activity (PA), yet interactions between these factors in predicting PA are infrequently studied. This analysis examines the independent associations and interactions between self-reported neighborhood and psychosocial variables in relation to moderate to vigorous PA (MVPA) among adults from a US panel sample. In adjusted models, neighborhood social capital was positively associated with meeting MVPA guidelines. Fewer barriers, greater self-efficacy, and greater autonomous motivation also corresponded with greater odds of meeting MVPA guidelines. An interaction between social capital and autonomous motivation showed that social capital was only associated with MVPA when autonomous motivation was high. Participants who reported both high autonomous motivation and high social capital were most likely to meet MVPA guidelines. Neighborhood social capital, barriers, self-efficacy, and autonomous motivation may be important correlates in promoting adults' PA. Future directions include using objective neighborhood and PA data in similar analyses and investigating associations of neighborhood and psychosocial variables with multiple PA activities. Intervention research to promote PA should also examine whether effects of interventions targeting psychosocial constructs are moderated by features of an individual's neighborhood or whether perceived social capital can be addressed in interventions in conjunction with psychosocial variables.

The influence of human physical activity and contaminated clothing type on particle resuspension.

PubMed

McDonagh, A; Byrne, M A

2014-01-01

A study was conducted to experimentally quantify the influence of three variables on the level of resuspension of hazardous aerosol particles from clothing. Variables investigated include physical activity level (two levels, low and high), surface type (four different clothing material types), and time i.e. the rate at which particles resuspend. A mixture of three monodisperse tracer-labelled powders, with median diameters of 3, 5, and 10 microns, was used to "contaminate" the samples, and the resuspended particles were analysed in real-time using an Aerodynamic Particle Sizer (APS), and also by Neutron Activation Analysis (NAA). The overall finding was that physical activity resulted in up to 67% of the contamination deposited on clothing being resuspended back into the air. A detailed examination of the influence of physical activity level on resuspension, from NAA, revealed that the average resuspended fraction (RF) of particles at low physical activity was 28 ± 8%, and at high physical activity was 30 ± 7%, while the APS data revealed a tenfold increase in the cumulative mass of airborne particles during high physical activity in comparison to that during low physical activity. The results also suggest that it is not the contaminated clothing's fibre type which influences particle resuspension, but the material's weave pattern (and hence the material's surface texture). Investigation of the time variation in resuspended particle concentrations indicated that the data were separable into two distinct regimes: the first (occurring within the first 1.5 min) having a high, positive rate of change of airborne particle concentration relative to the second regime. The second regime revealed a slower rate of change of particle concentration and remained relatively unchanged for the remainder of each resuspension event. Copyright © 2013 Elsevier Ltd. All rights reserved.

Spatial heterogeneity of within-stream methane concentrations

USGS Publications Warehouse

Crawford, John T.; Loken, Luke C.; West, William E.; Crary, Benjamin; Spawn, Seth A.; Gubbins, Nicholas; Jones, Stuart E.; Striegl, Robert G.; Stanley, Emily H.

2017-01-01

Streams, rivers, and other freshwater features may be significant sources of CH4 to the atmosphere. However, high spatial and temporal variabilities hinder our ability to understand the underlying processes of CH4 production and delivery to streams and also challenge the use of scaling approaches across large areas. We studied a stream having high geomorphic variability to assess the underlying scale of CH4 spatial variability and to examine whether the physical structure of a stream can explain the variation in surface CH4. A combination of high-resolution CH4 mapping, a survey of groundwater CH4 concentrations, quantitative analysis of methanogen DNA, and sediment CH4 production potentials illustrates the spatial and geomorphic controls on CH4 emissions to the atmosphere. We observed significant spatial clustering with high CH4 concentrations in organic-rich stream reaches and lake transitions. These sites were also enriched in the methane-producing mcrA gene and had highest CH4 production rates in the laboratory. In contrast, mineral-rich reaches had significantly lower concentrations and had lesser abundances of mcrA. Strong relationships between CH4and the physical structure of this aquatic system, along with high spatial variability, suggest that future investigations will benefit from viewing streams as landscapes, as opposed to ecosystems simply embedded in larger terrestrial mosaics. In light of such high spatial variability, we recommend that future workers evaluate stream networks first by using similar spatial tools in order to build effective sampling programs.

Comparison of Two Grid Refinement Approaches for High Resolution Regional Climate Modeling: MPAS vs WRF

NASA Astrophysics Data System (ADS)

Leung, L.; Hagos, S. M.; Rauscher, S.; Ringler, T.

2012-12-01

This study compares two grid refinement approaches using global variable resolution model and nesting for high-resolution regional climate modeling. The global variable resolution model, Model for Prediction Across Scales (MPAS), and the limited area model, Weather Research and Forecasting (WRF) model, are compared in an idealized aqua-planet context with a focus on the spatial and temporal characteristics of tropical precipitation simulated by the models using the same physics package from the Community Atmosphere Model (CAM4). For MPAS, simulations have been performed with a quasi-uniform resolution global domain at coarse (1 degree) and high (0.25 degree) resolution, and a variable resolution domain with a high-resolution region at 0.25 degree configured inside a coarse resolution global domain at 1 degree resolution. Similarly, WRF has been configured to run on a coarse (1 degree) and high (0.25 degree) resolution tropical channel domain as well as a nested domain with a high-resolution region at 0.25 degree nested two-way inside the coarse resolution (1 degree) tropical channel. The variable resolution or nested simulations are compared against the high-resolution simulations that serve as virtual reality. Both MPAS and WRF simulate 20-day Kelvin waves propagating through the high-resolution domains fairly unaffected by the change in resolution. In addition, both models respond to increased resolution with enhanced precipitation. Grid refinement induces zonal asymmetry in precipitation (heating), accompanied by zonal anomalous Walker like circulations and standing Rossby wave signals. However, there are important differences between the anomalous patterns in MPAS and WRF due to differences in the grid refinement approaches and sensitivity of model physics to grid resolution. This study highlights the need for "scale aware" parameterizations in variable resolution and nested regional models.

The development of early pulsation theory, or, how Cepheids are like steam engines"

NASA Astrophysics Data System (ADS)

Stanley, Matthew

2011-05-01

The pulsation theory of Cepheid variable stars was a major breakthrough of early twentieth-century astrophysics. At the beginning of that century, the basic physics of normal stars was very poorly understood, and variable stars were even more mysterious. Breaking with accepted explanations in terms of eclipsing binaries, Harlow Shapley and A.S. Eddington pioneered novel theories that considered Cepheids as pulsating spheres of gas. These theoretical models relied on highly speculative physics, but nonetheless returned very impressive results despite attacks from figures such as James Jeans. Surprisingly, the pulsation theory not only depended on developments in stellar physics, but also drove many of those developments. In particular, models of stars in radiative balance and theories of stellar energy were heavily inspired and shaped by ideas about variable stars. Further, the success of the pulsation theory helped justify the new approaches to astrophysics being developed before World War II.

Top-quark pairs at high invariant mass: a model-independent discriminator of new physics at the Large Hadron Collider.

PubMed

Barger, Vernon; Han, Tao; Walker, Devin G E

2008-01-25

We study top-quark pair production to probe new physics at the CERN Large Hadron Collider. We propose reconstruction methods for tt[over] semileptonic events and use them to reconstruct the tt[over] invariant mass. The angular distribution of top quarks in their c.m. frame can determine the spin and production subprocess for each new physics resonance. Forward-backward asymmetry and CP-odd variables can be constructed to further delineate the nature of new physics. We parametrize the new resonances with a few generic parameters and show high invariant mass top pair production may provide an early indicator for new physics beyond the standard model.

Physical activity and associated factors in high-school adolescents in Southern Brazil.

PubMed

Fermino, Rogério César; Rech, Cassiano Ricardo; Hino, Adriano Akira Ferreira; Rodriguez Añez, Ciro Romelio; Reis, Rodrigo Siqueira

2010-12-01

To estimate the prevalence of physical activity in adolescents and to identify associated factors. A cross-sectional study was conducted with a representative sample (n=1,518, 59.2% females) of students aged between 14 and 18 years, enrolled in the public school network of the city of Curitiba, Southern Brazil, in 2006. Physical activity practice was self-reported, according to the number of days per week when they perform moderate to vigorous physical activity lasting > 60 minutes. This practice was analyzed in two distinct models. In the first model, the variable was dichotomized into "0 day" and "> 1 day"; in the second, into "< 4 days" and "> 5 days". Independent variables were as follows: biological-demographic (sex, age, body mass index); socioeconomic (parents' level of education, number of cars); behavioral (number of hours spent watching television, number of hours spent using a computer); and sociocultural (social support from family and friends and the perception of barriers to the practice of activities), tested with Poisson regression. In the first model of analysis, the prevalence of physical activity was 58.2% (75.1% in males; 46.5% in females; p<0.001), while, in the second, it was 14.5% (22.3% and 9.1%, respectively; p<0.001). In the first model, the variables associated with physical activity were: male sex (PR=1.63, 95% CI: 1.48;1.78), social support from family (PR=1.14, 95% CI: 1.05;1.23), social support from friends (PR=1.52, 95% CI: 1.31;1.78) and high perception of barriers (PR=0.54, 95% CI: 0.46;0.62). In the second model, only male sex (PR=2.45, 95% CI: 1.73;3.46) and high perception of barriers (PR=0.24, 95% CI: 0.15;0.38) were associated with physical activity. More than half of adolescents practice physical activity at least one day of the week, although 14.5% achieved the current recommendations. The recommended levels are associated with a lower number of factors. Gender and perception of barriers were consistently associated with physical activity levels.

Change in the magnitude and mechanisms of global temperature variability with warming.

PubMed

Brown, Patrick T; Ming, Yi; Li, Wenhong; Hill, Spencer A

2017-01-01

Natural unforced variability in global mean surface air temperature (GMST) can mask or exaggerate human-caused global warming, and thus a complete understanding of this variability is highly desirable. Significant progress has been made in elucidating the magnitude and physical origins of present-day unforced GMST variability, but it has remained unclear how such variability may change as the climate warms. Here we present modeling evidence that indicates that the magnitude of low-frequency GMST variability is likely to decline in a warmer climate and that its generating mechanisms may be fundamentally altered. In particular, a warmer climate results in lower albedo at high latitudes, which yields a weaker albedo feedback on unforced GMST variability. These results imply that unforced GMST variability is dependent on the background climatological conditions, and thus climate model control simulations run under perpetual preindustrial conditions may have only limited relevance for understanding the unforced GMST variability of the future.

Change in the Magnitude and Mechanisms of Global Temperature Variability with Warming

NASA Astrophysics Data System (ADS)

Brown, P. T.; Ming, Y.; Li, W.; Hill, S. A.

2017-12-01

Natural unforced variability in global mean surface air temperature (GMST) can mask or exaggerate human-caused global warming, and thus a complete understanding of this variability is highly desirable. Significant progress has been made in elucidating the magnitude and physical origins of present-day unforced GMST variability, but it has remained unclear how such variability may change as the climate warms. Here we present modeling evidence that indicates that the magnitude of low-frequency GMST variability is likely to decline in a warmer climate and that its generating mechanisms may be fundamentally altered. In particular, a warmer climate results in lower albedo at high latitudes, which yields a weaker albedo feedback on unforced GMST variability. These results imply that unforced GMST variability is dependent on the background climatological conditions, and thus climate model control simulations run under perpetual preindustrial conditions may have only limited relevance for understanding the unforced GMST variability of the future.

Cardiac Autonomic Function and Psychological Characteristics of Heterosexual Female Perpetrators of Intimate Partner Physical Aggression.

PubMed

Brzozowski, Artur; Gillespie, Steven M; Dixon, Louise; Mitchell, Ian J

2018-05-01

Intimate partner violence is predominantly viewed as a social problem of men's violence against women. However, a growing evidence base suggests an equal prevalence rate for male and female perpetrated intimate partner physical aggression. Moreover, female perpetrated intimate partner violence is often assumed to be reactive, yet there is limited evidence to support this notion. In this article, we describe the results of two studies that investigated the prevalence of female perpetrated intimate partner physical aggression, and its correlates in heterosexual female university students. The relationships of personality traits, resting heart rate, and heart rate variability (a correlate of vagal activity) were compared between females who did and did not report having engaged in intimate partner physical aggression. In Study 1, we found that 30.9% of participants reported enacting intimate partner physical aggression during the preceding 12 months. This finding suggests that a considerable number of undergraduate females aggress against their intimate partners. Perpetrators, relative to nonperpetrators, scored higher on secondary psychopathic traits. In Study 2, female intimate partner violence was shown to be associated with low resting heart rate and high heart rate variability. Perpetrators, relative to nonperpetrators, scored higher on psychopathic traits that index emotional resilience and unempathic tendencies, and reported increased proactive and reactive aggression. This raises the possibility that some incidences of female intimate partner physical aggression represent proactive aggressive acts. These findings also support the frequently found association between low resting heart rate and aggression, but raise the prospect that the reported aggressive acts reflect high heart rate variability and strong parasympathetic nervous system activity.

Association between physical activity, participation in Physical Education classes, and social isolation in adolescents.

PubMed

Santos, Simone José dos; Hardman, Carla Menêses; Barros, Simone Storino Honda; Santos da Franca, Carolina; Santos, Carolina da F B F; Barros, Mauro Virgilio Gomes de

2015-01-01

To analyze the association between physical activity, participation in Physical Education classes, and indicators of social isolation among adolescents. This was an epidemiological study based on secondary analysis of data from a representative sample of students (14-19 years) from public high schools (n=4,207). Data were collected through the questionnaire Global School-based Student Health Survey. The independent variables were the level of physical activity and enrollment in Physical Education classes, while the dependent variables were two indicators of social isolation (feeling of loneliness and having few friends). Descriptive and inferential procedures were used in the statistical analysis. Most of the adolescents were classified as insufficiently active (65.1%) and reported not attending Physical Education classes (64.9%). Approximately two in each ten participants reported feeling of loneliness (15.8%) and, in addition, about one in each five adolescents reported have only one friend (19.5%). In the bivariate analysis, a significantly lower proportion of individuals reporting social isolation was observed among adolescents who referred higher enrollment in Physical Education classes. After adjustment for confounding variables, binary logistic regression showed that attending Physical Education classes was identified as a protective factor in relation to the indicator of social isolation 'having few friends,' but only for girls. It was concluded that participation in Physical Education classes is associated with reduced social isolation among female adolescents. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Assessing factors related to waist circumference and obesity: application of a latent variable model.

PubMed

Dalvand, Sahar; Koohpayehzadeh, Jalil; Karimlou, Masoud; Asgari, Fereshteh; Rafei, Ali; Seifi, Behjat; Niksima, Seyed Hassan; Bakhshi, Enayatollah

2015-01-01

Because the use of BMI (Body Mass Index) alone as a measure of adiposity has been criticized, in the present study our aim was to fit a latent variable model to simultaneously examine the factors that affect waist circumference (continuous outcome) and obesity (binary outcome) among Iranian adults. Data included 18,990 Iranian individuals aged 20-65 years that are derived from the third National Survey of Noncommunicable Diseases Risk Factors in Iran. Using latent variable model, we estimated the relation of two correlated responses (waist circumference and obesity) with independent variables including age, gender, PR (Place of Residence), PA (physical activity), smoking status, SBP (Systolic Blood Pressure), DBP (Diastolic Blood Pressure), CHOL (cholesterol), FBG (Fasting Blood Glucose), diabetes, and FHD (family history of diabetes). All variables were related to both obesity and waist circumference (WC). Older age, female sex, being an urban resident, physical inactivity, nonsmoking, hypertension, hypercholesterolemia, hyperglycemia, diabetes, and having family history of diabetes were significant risk factors that increased WC and obesity. Findings from this study of Iranian adult settings offer more insights into factors associated with high WC and high prevalence of obesity in this population.

Interstellar scintillation as the origin of the rapid radio variability of the quasar J1819+3845.

PubMed

Dennett-Thorpe, J; de Bruyn, A G

2002-01-03

The liberation of gravitational energy as matter falls onto a supermassive black hole at the centre of a galaxy is believed to explain the high luminosity of quasars. The variability of this emission from quasars and other types of active galactic nuclei can provide information on the size of the emitting regions and the physical process of fuelling the black hole. Some active galactic nuclei are variable at optical (and shorter) wavelengths, and display radio outbursts over years and decades. These active galactic nuclei often also show faster intraday variability at radio wavelengths. The origin of this rapid variability has been extensively debated, but a correlation between optical and radio variations in some sources suggests that both are intrinsic. This would, however, require radiation brightness temperatures that seem physically implausible, leading to the suggestion that the rapid variations are caused by scattering of the emission by the interstellar medium inside our Galaxy. Here we show that the rapid variations in the extreme case of quasar J1819+3845 (ref. 10) indeed arise from interstellar scintillation. The transverse velocity of the scattering material reveals the presence of plasma with a surprisingly high velocity close to the Solar System.

Assessing water source and channel type as factors affecting benthic macroinvertebrate and periphyton assemblages in the highly urbanized Santa Ana River Basin, California

USGS Publications Warehouse

Burton, Carmen; Brown, Larry R.; Belitz, Kenneth

2005-01-01

The Santa Ana River basin is the largest stream system in Southern California and includes a densely populated coastal area. Extensive urbanization has altered the geomorphology and hydrology of the streams, adversely affecting aquatic communities. We studied macroinvertebrate and periphyton assemblages in relation to two categorical features of the highly engineered hydrologic system-water source and channel type. Four water sources were identified-natural, urban-impacted groundwater, urban runoff, and treated wastewater. Three channel types were identified-natural, channelized with natural bottom, and concrete-lined. Nineteen sites, covering the range of these two categorical features, were sampled in summer 2000. To minimize the effects of different substrate types among sites, artificial substrates were used for assessing macroinvertebrate and periphyton assemblages. Physical and chemical variables and metrics calculated from macroinvertebrate and periphyton assemblage data were compared among water sources and channel types using analysis of variance and multiple comparison tests. Macroinvertebrate metrics exhibiting significant (P < 0.05) differences between water sources included taxa and Ephemeroptera-Plecoptera-Trichoptera richness, relative richness and abundance of nonchironomid dipterans, orthoclads, oligochaetes, and some functional-feeding groups such as parasites and shredders. Periphyton metrics showing significant differences between water sources included blue-green algae biovolume and relative abundance of nitrogen heterotrophic, eutrophic, motile, and pollution-sensitive diatoms. The relative abundance of trichopterans, tanytarsini chironomids, noninsects, and filter feeders, as well as the relative richness and abundance of diatoms, were significantly different between channel types. Most physical variables were related to channel type, whereas chemical variables and some physical variables (e.g., discharge, velocity, and channel width) were related to water source. These associations were reflected in correlations between metrics, chemical variables, and physical variables. Significant improvements in the aquatic ecosystem of the Santa Ana River basin are possible with management actions such as conversion of concrete-lined channels to channelized streams with natural bottoms that can still maintain flood control to protect life and property.

Symbolic dynamics marker of heart rate variability combined with clinical variables enhance obstructive sleep apnea screening

NASA Astrophysics Data System (ADS)

Ravelo-García, A. G.; Saavedra-Santana, P.; Juliá-Serdá, G.; Navarro-Mesa, J. L.; Navarro-Esteva, J.; Álvarez-López, X.; Gapelyuk, A.; Penzel, T.; Wessel, N.

2014-06-01

Many sleep centres try to perform a reduced portable test in order to decrease the number of overnight polysomnographies that are expensive, time-consuming, and disturbing. With some limitations, heart rate variability (HRV) has been useful in this task. The aim of this investigation was to evaluate if inclusion of symbolic dynamics variables to a logistic regression model integrating clinical and physical variables, can improve the detection of subjects for further polysomnographies. To our knowledge, this is the first contribution that innovates in that strategy. A group of 133 patients has been referred to the sleep center for suspected sleep apnea. Clinical assessment of the patients consisted of a sleep related questionnaire and a physical examination. The clinical variables related to apnea and selected in the statistical model were age (p < 10-3), neck circumference (p < 10-3), score on a questionnaire scale intended to quantify daytime sleepiness (p < 10-3), and intensity of snoring (p < 10-3). The validation of this model demonstrated an increase in classification performance when a variable based on non-linear dynamics of HRV (p < 0.01) was used additionally to the other variables. For diagnostic rule based only on clinical and physical variables, the corresponding area under the receiver operating characteristic (ROC) curve was 0.907 (95% confidence interval (CI) = 0.848, 0.967), (sensitivity 87.10% and specificity 80%). For the model including the average of a symbolic dynamic variable, the area under the ROC curve was increased to 0.941 (95% = 0.897, 0.985), (sensitivity 88.71% and specificity 82.86%). In conclusion, symbolic dynamics, coupled with significant clinical and physical variables can help to prioritize polysomnographies in patients with a high probability of apnea. In addition, the processing of the HRV is a well established low cost and robust technique.

Prevalence and correlates of physical fitness testing in U.S. schools--2000.

PubMed

Morrow, James R; Fulton, Janet E; Brener, Nancy D; Kohl, Harold W

2008-06-01

Because of the perceived lack of youth physical fitness and/or concerns for increased obesity, physical education teachers are interested in youth fitness and physical activity levels. Statewide mandates are being developed that require school-based teachers to complete physical fitness testing. Data from the nationally representative School Health Policies and Programs Study 2000 were analyzed to investigate the prevalence of fitness testing and the professional characteristics of fitness test users. Data were collected with teachers of either randomly selected classes in elementary schools and randomly selected required physical education courses in middle/junior high and senior high schools (N = 1,564). The prevalence of fitness test use is 65% across all school levels. Variables associated with physical fitness test usage were professionally oriented. Results showed that teachers in secondary schools (odds ratio [OR] = 2.25, 95% confidence interval [CI] = I.18-4.27), those with degrees in physical education/kinesiology-related disciplines (OR = 2.01, 95% CI = 1.11-3.63), and those who had completed staff development on physical fitness testing (OR = 3.22, 95% CI = 1.86-5.60) were more likely than respondents without these characteristics to engage in physical fitness testing. Results changed little when separate analyses were conducted for classes/courses in districts requiring versus not requiring fitness testing. Financial variables, including fitness-oriented facilities available, metropolitan location, and discretionary expenditures per student, were not associated with fitness test use. Results provided national prevalence of school-based physical fitness testing use in the U. S. and conveyed information about those who currently use physical fitness tests.

Exploring the Variability of the Fermi LAT Blazar Population

NASA Astrophysics Data System (ADS)

Macomb, Daryl J.; Shrader, C. R.

2014-01-01

The flux variability of the approximately 2000 point sources cataloged by the Fermi Gamma-Ray Space Telescope provide important clues to population characteristics. This is particularly true of the more than 1100 source that are likely AGN. By characterizing the intrinsic flux variability and distinguishing this variability from flaring behavior, we can better address questions of flare amplitudes, durations, recurrence times, and temporal profiles. A better understanding of the responsible physical environments, such as the scale and location of jet structures responsible for the high-energy emission, may emerge from such studies. Assessing these characteristics as a function of blazar sub-class is a further goal in order to address questions about the fundamentals of blazar AGN physics. Here we report on progress made in categorizing blazar flare behavior, and correlate these behaviors with blazar sub-type and other source parameters.

Social Cognitive Theory and Physical Activity Among Korean Male High-School Students.

PubMed

Lee, Chung Gun; Park, Seiyeong; Lee, Seung Hwan; Kim, Hyunwoo; Park, Ji-Won

2018-02-01

The most critical step in developing and implementing effective physical activity interventions is to understand the determinants and correlates of physical activity, and it is strongly suggested that such effort should be based on theories. The purpose of this study is to test the direct, indirect, and total effect of social cognitive theory constructs on physical activity among Korean male high-school students. Three-hundred and forty-one 10th-grade male students were recruited from a private single-sex high school located in Seoul, South Korea. Structural equation modeling was used to test the expected relationships among the latent variables. The proposed model accounted for 42% of the variance in physical activity. Self-efficacy had the strongest total effect on physical activity. Self-efficacy for being physically active was positively associated with physical activity ( p < .01). Self-efficacy also had positive indirect effects on physical activity through perceived benefits ( p < .05) and goal setting ( p < .01). The results of this study indicated that the social cognitive theory is a useful framework to understand physical activity among Korean male adolescents. Physical activity interventions targeting Korean male high-school students should focus on the major sources of efficacy.

Growing old with fibromyalgia: factors that predict physical function.

PubMed

Torma, Linda M; Houck, Gail M; Wagnild, Gail M; Messecar, Deborah; Jones, Kim Dupree

2013-01-01

Fibromyalgia, a persistent, widespread pain condition, significantly limits physical function, threatening an older adult's health and ability to live independently. The aim of the study was to identify predictors of physical function in older adults living with fibromyalgia and to examine the influence of resilience on the relationship between fibromyalgia pain and physical function. This was a descriptive correlational, cross-sectional design using mailed questionnaires to analyze relationships between health-related variables and physical function in a convenience sample of community-dwelling older adults diagnosed with fibromyalgia (n = 224; age M = 62.1 years, SD = 6.75 years). Multiple regression was used to identify a priori predictors of physical function; hierarchical multiple regression was used to examine resilience as a moderator of pain and physical function. The sample was predominantly women, Caucasian, married, well educated, had moderate levels of income and tangible social support, and had low levels of physical function. Three-fourths were overweight or obese. Despite impaired physical function (Late Life Function and Disability Index, M = 51.5/100, SD = 9) and moderate levels of pain (Numeric Rating Scale, M = 5.47/10, SD = 2.6), resilience was moderately high (Resilience Scale, M = 137/175, SD = 20). An eight-variable disablement-based model accounted for 48% of variance in physical function: age, income, education, depressive symptoms, body mass index, and physical activity accounted for 31%; pain added 14%; and resilience contributed an additional 3%. Resilience was not a moderator of fibromyalgia pain and physical function; resilience did contribute uniquely to physical function variance. Resilience, a novel variable in fibromyalgia research, was a unique predictor of physical function. Further research is needed to learn more about the relationships between resilience, fibromyalgia impact, and the aging process.

[Factors associated with participation in sports and physical education among students from Londrina, Paraná State, Brazil].

PubMed

Coledam, Diogo Henrique Constantino; Ferraiol, Philippe Fanelli; Pires Junior, Raymundo; dos-Santos, Júlio Wilson; Oliveira, Arli Ramos de

2014-03-01

This study aimed to analyze factors associated with participation in sports and physical education. The sample consisted of 827 young people selected in two stages and stratified by neighborhood of Londrina, Paraná State, Brazil. The study analyzed participation in sports and physical education in relation to socio-demographic, behavioral, and environmental variables. Factors associated with participation in physical education included: male gender, age (10-13 years), equal to high self-rated physical activity, participation in sports, moving around during classes, and having classes on the court. Factors associated with participation in sports were male gender, age (10-13 years), equal to high self-rated physical activity, physical activity (≥ 7 hours/week), participation in physical education, having ≥ 10 friends, participation in sports with friends, and frequency using facilities for sports practice. These factors should be considered in programs to encourage sports and participation in physical education.

Investigating Visually Disabled Students' Attitudes about Physical Education and Sport

ERIC Educational Resources Information Center

Dalbudak, Ibrahim; Gürkan, Alper C.; Yigit, Sih Mehmet; Kargun, Mehmet; Hazar, Gürkan; Dorak, Feridun

2016-01-01

This study aims to investigate visually disabled students', who study in the level of primary education, high school, university, attitudes about physical education and sport in terms of different variables. Totally 100 visually disabled students who are individual and team athletes and study in Izmir, (8 visually disabled athletes study in…

The Effects Of An Exercise Physiology Program on Physical Fitness Variables, Body Satisfaction, and Physiology Knowledge.

ERIC Educational Resources Information Center

Perry, Arlette C.; Rosenblatt, Evelyn S.; Kempner, Lani; Feldman, Brandon B.; Paolercio, Maria A.; Van Bemden, Angie L.

2002-01-01

Examined the effects of an exercise physiology program on high school students' physical fitness, body satisfaction, and physiology knowledge. Intervention students received exercise physiology theory and active aerobic and resistance exercise within their biology course. Data from student surveys and measurements indicated that the integrated…

Success in everyday physics: The role of personality and academic variables

NASA Astrophysics Data System (ADS)

Norvilitis, Jill M.; Reid, Howard M.; Norvilitis, Bret M.

2002-05-01

Two studies examined students' intuitive physics ability and characteristics associated with physics competence. In Study 1, although many students did well on a physics quiz, more than 25% of students performed below levels predicted by chance. Better performance on the physics quiz was related to physics grades, highest level of math taken, and students' perceived scholastic competence, but was not related to a number of other hypothesized personality variables. Study 2 further explored personality and academic variables and also examined students' awareness of their own physics ability. Results indicate that the personality variables were again unrelated to ability, but narcissism may be related to subjects' estimates of knowledge. Also, academic variables and how important students think it is to understand the physical world are related to both measured and estimated physics proficiency.

Goal orientation, motivational climate, and dispositional flow of high school students engaged in extracurricular physical activity.

PubMed

Cervelló, Eduardo M; Moreno, Juan A; Villodre, Nestor Alonso; Iglesias, Damián

2006-02-01

The purpose of this study was to examine the role of goal orientation, motivational climate, and dispositional flow in physical education lessons on extracurricular involvement in physical activity. Questionnaires were administered to 1,103 (792 athletes; 311 nonathletes) secondary school students (M age = 14.3 yr., SD = 0.7). Analysis showed significant mean differences between groups on goal orientation and dispositional flow in physical education lessons, but none for perception of motivational climate. These findings suggest that dispositional variables are related to extracurricular involvement in physical activity.

Report of the solar physics panel

NASA Technical Reports Server (NTRS)

Withbroe, George L.; Fisher, Richard R.; Antiochos, Spiro; Brueckner, Guenter; Hoeksema, J. Todd; Hudson, Hugh; Moore, Ronald; Radick, Richard R.; Rottman, Gary; Scherrer, Philip

1991-01-01

Recent accomplishments in solar physics can be grouped by the three regions of the Sun: the solar interior, the surface, and the exterior. The future scientific problems and areas of interest involve: generation of magnetic activity cycle, energy storage and release, solar activity, solar wind and solar interaction. Finally, the report discusses a number of future space mission concepts including: High Energy Solar Physics Mission, Global Solar Mission, Space Exploration Initiative, Solar Probe Mission, Solar Variability Explorer, Janus, as well as solar physics on Space Station Freedom.

An experimental investigation of the flow physics of high-lift systems

NASA Technical Reports Server (NTRS)

Thomas, Flint O.; Nelson, R. C.

1995-01-01

This progress report is a series of overviews outlining experiments on the flow physics of confluent boundary layers for high-lift systems. The research objectives include establishing the role of confluent boundary layer flow physics in high-lift production; contrasting confluent boundary layer structures for optimum and non-optimum C(sub L) cases; forming a high quality, detailed archival data base for CFD/modelling; and examining the role of relaminarization and streamline curvature. Goals of this research include completing LDV study of an optimum C(sub L) case; performing detailed LDV confluent boundary layer surveys for multiple non-optimum C(sub L) cases; obtaining skin friction distributions for both optimum and non-optimum C(sub L) cases for scaling purposes; data analysis and inner and outer variable scaling; setting-up and performing relaminarization experiments; and a final report establishing the role of leading edge confluent boundary layer flow physics on high-lift performance.

Comparison of technical and physical activities between 8 vs. 8 and 11 vs. 11 games in young Korean soccer players.

PubMed

Oh, Seong Hwan; Joo, Chang Hwa

2018-04-01

The aims of this study were to examine the differences in technical aspects and physical demands between small-size games (SSG; 8 vs. 8) and regular-size games (RSG; 11 vs. 11) in young Korean soccer players. Seventy-nine young soccer players from 6 teams (U-12) volunteered to participate in the study. The players completed 4 games (2 SSG, 62×51 m, and 2 RSG, 80×54 m) in 2 days. Each game was filmed to evaluate technical actions. Physical demand variables were measured using global positioning system technology. SSG showed significantly greater numbers of technical plays among 17 variables when compared to RSG ( P <0.05). The players covered significantly greater total distance during low-, moderate-, and high-speed running and sprinting in SSG than in RSG ( P <0.05). Higher numbers of high-intensity activities (repeated high-intensity efforts, explosive efforts, decelera-tions, accelerations, and sprinting) were observed in SSG compared to RSG ( P <0.05). Mean heart rate was also higher in SSG than in RSG ( P <0.05). Despite the greater physical demands during SSG, the exercise intensity was similar to that reported in previous studies. Therefore, the SSG format applied in the present study can be a suitable official game format for Korean young soccer players, resulting in significantly greater exposure to technical plays without excessive physical demands.

Soil properties discriminating Araucaria forests with different disturbance levels.

PubMed

Bertini, Simone Cristina Braga; Azevedo, Lucas Carvalho Basilio; Stromberger, Mary E; Cardoso, Elke Jurandy Bran Nogueira

2015-04-01

Soil biological, chemical, and physical properties can be important for monitoring soil quality under one of the most spectacular vegetation formation on Atlantic Forest Biome, the Araucaria Forest. Our aim was to identify a set of soil variables capable of discriminating between disturbed, reforested, and native Araucaria forest soils such that these variables could be used to monitor forest recovery and maintenance. Soil samples were collected at dry and rainy season under the three forest types in two state parks at São Paulo State, Brazil. Soil biological, chemical, and physical properties were evaluated to verify their potential to differentiate the forest types, and discriminant analysis was performed to identify the variables that most contribute to the differentiation. Most of physical and chemical variables were sensitive to forest disturbance level, but few biological variables were significantly different when comparing native, reforested, and disturbed forests. Despite more than 20 years following reforestation, the reforested soils were chemically and biologically distinct from native and disturbed forest soils, mainly because of the greater acidity and Al3+ content of reforested soil. Disturbed soils, in contrast, were coarser in texture and contained greater concentrations of extractable P. Although biological properties are generally highly sensitive to disturbance and amelioration efforts, the most important soil variables to discriminate forest types in both seasons included Al3+, Mg2+, P, and sand, and only one microbial attribute: the NO2- oxidizers. Therefore, these five variables were the best candidates, of the variables we employed, for monitoring Araucaria forest disturbance and recovery.

Risk factors for childhood obesity in elementary school-age Taiwanese children.

PubMed

Chen, Jyu-Lin; Kennedy, Christine; Yeh, Chao-Hsing; Kools, Susan

2005-01-01

A cross-sectional study design was used to examine factors that contribute to high relative weight in children in Taiwan. A total sample of 331 Chinese children (ages 7 and 8) and their parents participated in the study. Parents completed questionnaires regarding demographic information, family functioning, parenting styles, physical activity, and dietary intake. Children completed physical fitness tests and questionnaires regarding physical activity, dietary intake, coping strategies, and self-esteem. The weight-for-length index was used to measure children's relative weight. The findings revealed that four variables contributed to higher weight-for-length index in boys compared with girls and explained 37.7% of the variance: high maternal body mass index, poor aerobic capacity, healthy family role functioning, and poor family affective responsiveness. Two variables were found to contribute to higher weight-for-length index in girls and explained 12.8% of the variance: high household income and high maternal body mass index. Taken together, the results indicate the importance of assessment of children's weight status, maternal weight status, and family functioning as part of routine child health care and the need for developmentally appropriate and gender-specific approaches to prevent childhood obesity.

High Resolution Time Series Observations of Bio-Optical and Physical Variability in the Arabian Sea

DTIC Science & Technology

1998-09-30

1995-October 20, 1995). Multi-variable moored systems ( MVMS ) were deployed by our group at 35 and 80m. The MVMS utilizes a VMCM to measure currents...similar to that of the UCSB MVMSs. WORK COMPLETED Our MVMS interdisciplinary systems with sampling intervals of a few minutes were placed on a mooring

Differences within: A comparative analysis of women in the physical sciences --- Motivation and background factors

NASA Astrophysics Data System (ADS)

Dabney, Katherine Patricia Traudel

Science, technology, engineering, and mathematics (STEM) education has become a critical focus in the United States due to economic concerns and public policy (National Academy of Sciences, 2007; U.S. Department of Education, 2006). Part of this focus has been an emphasis on encouraging and evaluating career choice and persistence factors among underrepresented groups such as females in the physical sciences (Hill et al., 2010; National Academy of Sciences, 2007). The majority of existing STEM research studies compare women to men, yet a paucity of research exists that examines what differentiates female career choice within the physical sciences. In light of these research trends and recommendations, this study examines the following questions: 1. On average, do females who select chemistry or physics doctoral programs differ in their reported personal motivations and background factors prior to entering the field? 2. Do such variables as racial and ethnic background, age, highest level of education completed by guardians/parents, citizenship status, family interest in science, first interest in general science, first interest in the physical sciences, average grades in high school and undergraduate studies in the physical sciences, and experiences in undergraduate physical science courses explain a significant amount of variance in female physical scientists' years to Ph.D. completion? These questions are analyzed using variables from the Project Crossover Survey dataset through a subset of female physical science doctoral students and scientists. Logistic regression analyses are performed to uncover what differentiates women in the physical sciences based on their background, interest, academic achievement, and experiences ranging prior to elementary school through postsecondary education. Significant variables that positively predict a career choice in chemistry or physics include content specific high school and undergraduate academic achievement and positive undergraduate experiences. Two multiple regression models, one composed of female chemists and one of female physicists, examine significant predictors that positively associated with time to doctoral degree completion. The models account for little differentiation in the outcome of time to doctoral completion. In addition, significant predictors are based on demographic and achievement factors that were not paralleled in the two multiple regressions.

Particle Physics in High School: A Diagnose Study

PubMed Central

Solbes, Jordi

2016-01-01

The science learning process improves when the contents are connected to students’ lives. Particle physics has had a great impact in our society in the last years and has changed the theoretical picture about matter fundamental dynamics. Thus, we think that academic contents about matter components and interactions should be updated. With this study we aim to characterize the level of knowledge of high school students about this topic. We built a test with questions about classical atomic models, particle physics, recent discoveries, social implications and students opinions about it. Contrary to our first suspicion, students’ answers show a high variability. They have new physics ideas and show a great interest towards modern concepts. We suggest including an updated view of this topic as part of the curriculum. PMID:27253377

Particle Physics in High School: A Diagnose Study.

PubMed

Tuzón, Paula; Solbes, Jordi

2016-01-01

The science learning process improves when the contents are connected to students' lives. Particle physics has had a great impact in our society in the last years and has changed the theoretical picture about matter fundamental dynamics. Thus, we think that academic contents about matter components and interactions should be updated. With this study we aim to characterize the level of knowledge of high school students about this topic. We built a test with questions about classical atomic models, particle physics, recent discoveries, social implications and students opinions about it. Contrary to our first suspicion, students' answers show a high variability. They have new physics ideas and show a great interest towards modern concepts. We suggest including an updated view of this topic as part of the curriculum.

Insight and other predictors of physical examination refusal in psychotic illness.

PubMed

Iwata, Kazuya; Strydom, Andre; Osborn, David

2011-08-01

Poor physical health in psychiatric patients is well recognized, yet factors contributing to physical examination noncompliance in psychotic illness have not been previously studied. To examine whether insight or any other variables were independent predictors of physical examination noncompliance. A case-note study (N = 200) of inpatient psychiatric patients in four hospitals in London, UK was conducted to examine the relationship between insight and physical examination noncompliance within 24  h of admission and over 2 weeks. Clinical variables including illness severity were also examined. Patients who were noncompliant with physical examinations offered within 24  h and over 2 weeks were associated with lack of insight, higher illness severity, female gender, longer history of illness, current compulsory admission, and previous history of detention. After adjusting for confounding factors, lack of insight, female gender, and previous history of detention were found to be independent predictors of physical examination noncompliance for 24  h and 2 weeks. Lack of insight is highly predictive of physical examination noncompliance for up to 2 weeks, indicating that mental incapacity to consenting to medical care may be common and that more proactive physical screening may be required for these patients.

What makes patients with fibromyalgia feel better? Correlations between Patient Global Impression of Improvement and changes in clinical symptoms and function: a pooled analysis of 4 randomized placebo-controlled trials of duloxetine.

PubMed

Hudson, James I; Arnold, Lesley M; Bradley, Laurence A; Choy, Ernest H S; Mease, Philip J; Wang, Fujun; Ahl, Jonna; Wohlreich, Madelaine M

2009-11-01

To investigate the relationship between changes in clinical rating scale items and endpoint Patient Global Impression of Improvement (PGI-I). Data were pooled from 4 randomized, double-blind, placebo-controlled studies of duloxetine in patients with fibromyalgia (FM). Variables included in the analyses were those that assessed symptoms in FM domains of pain, fatigue, sleep, cognitive difficulties, emotional well-being, physical function, and impact on daily living. The association of endpoint PGI-I with changes from baseline in individual variables was assessed using Pearson product-moment correlations (r). Stepwise linear regression was used to identify those variables for which changes from baseline were statistically significant independent predictors of the endpoint PGI-I ratings. Changes in pain variables and interference of symptoms with the ability to work were highly correlated (r >or= 0.5 or r

Characterizing the γ-ray long-term variability of PKS 2155-304 with H.E.S.S. and Fermi-LAT

NASA Astrophysics Data System (ADS)

H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dubus, G.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hadasch, D.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kerszberg, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

2017-02-01

Studying the temporal variability of BL Lac objects at the highest energies provides unique insights into the extreme physical processes occurring in relativistic jets and in the vicinity of super-massive black holes. To this end, the long-term variability of the BL Lac object PKS 2155-304 is analyzed in the high (HE, 100 MeV < E < 300 GeV) and very high energy (VHE, E > 200 GeV) γ-ray domain. Over the course of 9 yr of H.E.S.S. observations the VHE light curve in the quiescent state is consistent with a log-normal behavior. The VHE variability in this state is well described by flicker noise (power-spectral-density index ) on timescales larger than one day. An analysis of 5.5 yr of HE Fermi-LAT data gives consistent results (, on timescales larger than 10 days) compatible with the VHE findings. The HE and VHE power spectral densities show a scale invariance across the probed time ranges. A direct linear correlation between the VHE and HE fluxes could neither be excluded nor firmly established. These long-term-variability properties are discussed and compared to the red noise behavior (β 2) seen on shorter timescales during VHE-flaring states. The difference in power spectral noise behavior at VHE energies during quiescent and flaring states provides evidence that these states are influenced by different physical processes, while the compatibility of the HE and VHE long-term results is suggestive of a common physical link as it might be introduced by an underlying jet-disk connection.

Longterm AGN variability in the BASS sample

NASA Astrophysics Data System (ADS)

Sartori, Lia; Schawinski, Kevin; Koss, Michael; Treister, Ezequiel

2018-01-01

The study of AGN variability on different timescales can provide important information about black hole accretion physics, as well as the black hole – host galaxy interaction and coevolution. Galaxies with extended AGN photoionised clouds, e.g. IC 2497 and “Hanny’s Voorwerp”, are a great laboratory to study AGN variability over 100 kyr timescales, especially in the case where the AGN is currently dropping in luminosity. Based on a large sample of optically elusive AGN in the BASS sample we suggest that AGN may ‘flicker’ on and off 100-1000 times on ~10^5 yr timescales, and that optically elusive AGN may provide information about the switching on phase. In this talk I will show how longslit and IFU observations of BASS sources, combined with high quality hard X-ray observations and black hole demographic information, can help constraining the AGN lifecycle, and ultimately what is the physics driving AGN variability.

Feeling Healthy? A Survey of Physical and Psychological Wellbeing of Students from Seven Universities in the UK

PubMed Central

Ansari, Walid El; Stock, Christiane; Snelgrove, Sherrill; Hu, Xiaoling; Parke, Sian; Davies, Shân; John, Jill; Adetunji, Hamed; Stoate, Mary; Deeny, Pat; Phillips, Ceri; Mabhala, Andi

2011-01-01

University students’ physical and psychological health and wellbeing are important and comprise many variables. This study assessed perceived health status in addition to a range of physical and psychological wellbeing indicators of 3,706 undergraduate students from seven universities in England, Wales and Northern Ireland. We compared differences in these variables across males and females, and across the participating universities. The data was collected in 2007–2008. A self-administered questionnaire assessed socio-demographic information (e.g., gender, age), self-reported physical and psychological health data, as well as questions on health awareness, health service use, social support, burdens and stressors and university study related questions. While females generally reported more health problems and psychological burdens, male students felt that they received/had fewer persons to depend on for social support. The comparisons of health and wellbeing variables across the different universities suggested some evidence of ‘clustering’ of the variables under study, whereby favourable situations would be exhibited by a cluster of the variables that is encountered at some universities; and conversely, the clustering of less favourable variables as exhibited at other universities. We conclude that the level of health complaints and psychological problems/burdens is relatively high and calls for increased awareness of university administrators, leaders and policy makers to the health and well-being needs of their students. The observed clustering effects also indicated the need for local (university-specific) health and wellbeing profiles as basis and guidance for relevant health promotion programmes at universities. PMID:21655121

Cardiovascular risk profile: cross-sectional analysis of motivational determinants, physical fitness and physical activity.

PubMed

Sassen, Barbara; Kok, Gerjo; Schaalma, Herman; Kiers, Henri; Vanhees, Luc

2010-10-07

Cardiovascular risk factors are associated with physical fitness and, to a lesser extent, physical activity. Lifestyle interventions directed at enhancing physical fitness in order to decrease the risk of cardiovascular diseases should be extended. To enable the development of effective lifestyle interventions for people with cardiovascular risk factors, we investigated motivational, social-cognitive determinants derived from the Theory of Planned Behavior (TPB) and other relevant social psychological theories, next to physical activity and physical fitness. In the cross-sectional Utrecht Police Lifestyle Intervention Fitness and Training (UP-LIFT) study, 1298 employees (aged 18 to 62) were asked to complete online questionnaires regarding social-cognitive variables and physical activity. Cardiovascular risk factors and physical fitness (peak VO2) were measured. For people with one or more cardiovascular risk factors (78.7% of the total population), social-cognitive variables accounted for 39% (p < .001) of the variance in the intention to engage in physical activity for 60 minutes every day. Important correlates of intention to engage in physical activity were attitude (beta = .225, p < .001), self-efficacy (beta = .271, p < .001), descriptive norm (beta = .172, p < .001) and barriers (beta = -.169, p < .01). Social-cognitive variables accounted for 52% (p < .001) of the variance in physical active behaviour (being physical active for 60 minutes every day). The intention to engage in physical activity (beta = .469, p < .001) and self-efficacy (beta = .243, p < .001) were, in turn, important correlates of physical active behavior.In addition to the prediction of intention to engage in physical activity and physical active behavior, we explored the impact of the intensity of physical activity. The intensity of physical activity was only significantly related to physical active behavior (beta = .253, p < .01, R2 = .06, p < .001). An important goal of our study was to investigate the relationship between physical fitness, the intensity of physical activity and social-cognitive variables. Physical fitness (R2 = .23, p < .001) was positively associated with physical active behavior (beta = .180, p < .01), self-efficacy (beta = .180, p < .01) and the intensity of physical activity (beta = .238, p < .01).For people with one or more cardiovascular risk factors, 39.9% had positive intentions to engage in physical activity and were also physically active, and 10.5% had a low intentions but were physically active. 37.7% had low intentions and were physically inactive, and about 11.9% had high intentions but were physically inactive. This study contributes to our ability to optimize cardiovascular risk profiles by demonstrating an important association between physical fitness and social-cognitive variables. Physical fitness can be predicted by physical active behavior as well as by self-efficacy and the intensity of physical activity, and the latter by physical active behavior.Physical active behavior can be predicted by intention, self-efficacy, descriptive norms and barriers. Intention to engage in physical activity by attitude, self-efficacy, descriptive norms and barriers. An important input for lifestyle changes for people with one or more cardiovascular risk factors was that for ca. 40% of the population the intention to engage in physical activity was in line with their actual physical active behavior.

Emotional distress and dysfunctional illness perception are associated with low mental and physical quality of life in Chinese breast cancer patients.

PubMed

Tang, Lili; Fritzsche, Kurt; Leonhart, Rainer; Pang, Ying; Li, Jinjiang; Song, Lili; Fischer, Irmela; Koch, Maike; Wuensch, Alexander; Mewes, Ricarda; Schaefert, Rainer

2017-12-01

To evaluate the relationship between quality of life (QOL) and physical as well as psychological variables in Chinese breast cancer patients. This multicenter cross-sectional study enrolled 254 Chinese breast cancer patients in different stages and treatment phases. They answered standard instruments assessing QOL (EORTC), somatic symptom severity (PHQ-15), depression (PHQ-9), anxiety (GAD-7), health-related anxiety (WI-7), illness perception (BIPQ), and sense of coherence (SOC-9). Canonical correlation was applied to identify the strongest correlates between the physical, emotional and social QOL scales and the physical and psychological variables. In our sample, a low global QOL was significantly associated with the following physical and psychological variables: symptom-related disability (Karnofsky Index) (r = .211, p < .01), somatic symptom severity (r = -.391, p < .001), depression (r = -.488, p < .001), anxiety (r = -.439, p < .001), health-related anxiety (r = -.398, p < .001), dysfunctional illness perception (r = -.411, p < .001), and sense of coherence (r = .371, p < .001). In the canonical correlation analysis, high somatic symptom severity, depression, anxiety, dysfunctional illness perception, and low sense of coherence showed the strongest correlations with low physical, emotional and social functioning. The first three significant canonical correlations between these two sets of variables were .78, .56, and .45. QOL in Chinese breast cancer patients is strongly associated with psychological factors. Our results suggest that Chinese physicians and nurses should incorporate these factors into their care for women with breast cancer to improve patients' QOL.

Change in the magnitude and mechanisms of global temperature variability with warming

PubMed Central

Brown, Patrick T.; Ming, Yi; Li, Wenhong; Hill, Spencer A.

2017-01-01

Natural unforced variability in global mean surface air temperature (GMST) can mask or exaggerate human-caused global warming, and thus a complete understanding of this variability is highly desirable. Significant progress has been made in elucidating the magnitude and physical origins of present-day unforced GMST variability, but it has remained unclear how such variability may change as the climate warms. Here we present modeling evidence that indicates that the magnitude of low-frequency GMST variability is likely to decline in a warmer climate and that its generating mechanisms may be fundamentally altered. In particular, a warmer climate results in lower albedo at high latitudes, which yields a weaker albedo feedback on unforced GMST variability. These results imply that unforced GMST variability is dependent on the background climatological conditions, and thus climate model control simulations run under perpetual preindustrial conditions may have only limited relevance for understanding the unforced GMST variability of the future. PMID:29391875

Variability of Metabolic Power Data in Elite Soccer Players During Pre-Season Matches

PubMed Central

Hoppe, Matthias Wilhelm; Baumgart, Christian; Slomka, Mirko; Polglaze, Ted; Freiwald, Jürgen

2017-01-01

Abstract This study aimed to determine the within-subject variability of GPS-derived metabolic power data in elite soccer players across several pre-season matches and compare the variability of high metabolic power, velocity, acceleration and deceleration running. Additionally, differences in metabolic power data among playing positions and relationships with various physical abilities were also investigated. Metabolic power data from 12 outfield starting players competing in the German Bundesliga were collected during five pre-season matches using GPS-technology (10 Hz). The players were also tested for speed, agility, power and intermittent endurance. Variability of global metabolic power data such as energy expenditure (CV = 2.2-7.0%) was lower than that for high-intensity including time ≥20 W·kg-1 (CV = 14.0-26.2%). Variability of high metabolic power (≥20 W·kg-1; CV = 14.1 ± 3.5%) was comparable to that of high velocity (≥15.5 km·h-1; CV = 17.0 ± 6.2%), acceleration (≥3 m·s-2; CV = 11.1 ± 5.1%) and deceleration running (≤-3 m·s-2; CV = 11.9 ± 4.5%) (p > 0.05, ES < 0.2). Defenders had a largely higher overall energy expenditure than midfielders and attackers (p < 0.01, ES > 0.6). Overall energy expenditure and cost were largely to very largely correlated with 5 m speed and 22 m agility sprint time and counter movement jump height (r = -0.70-0.69, p < 0.05). The detected variability indicates that global GPS-derived metabolic power data in elite soccer players from a single preseason match should be preferably used for practical applications. Contrary, high-intensity indicators should be interpreted cautiously and repeated match observations are recommended to establish meaningful high-intensity profiles of the players. Differences among playing positions and relationships with explosive physical abilities indicate that metabolic power analyses can provide new insights into the mechanics and energetics of soccer. PMID:28828094

Variability of Metabolic Power Data in Elite Soccer Players During Pre-Season Matches.

PubMed

Hoppe, Matthias Wilhelm; Baumgart, Christian; Slomka, Mirko; Polglaze, Ted; Freiwald, Jürgen

2017-09-01

This study aimed to determine the within-subject variability of GPS-derived metabolic power data in elite soccer players across several pre-season matches and compare the variability of high metabolic power, velocity, acceleration and deceleration running. Additionally, differences in metabolic power data among playing positions and relationships with various physical abilities were also investigated. Metabolic power data from 12 outfield starting players competing in the German Bundesliga were collected during five pre-season matches using GPS-technology (10 Hz). The players were also tested for speed, agility, power and intermittent endurance. Variability of global metabolic power data such as energy expenditure (CV = 2.2-7.0%) was lower than that for high-intensity including time ≥20 W·kg -1 (CV = 14.0-26.2%). Variability of high metabolic power (≥20 W·kg -1 ; CV = 14.1 ± 3.5%) was comparable to that of high velocity (≥15.5 km·h -1 ; CV = 17.0 ± 6.2%), acceleration (≥3 m·s -2 ; CV = 11.1 ± 5.1%) and deceleration running (≤-3 m·s -2 ; CV = 11.9 ± 4.5%) (p > 0.05, ES < 0.2). Defenders had a largely higher overall energy expenditure than midfielders and attackers (p < 0.01, ES > 0.6). Overall energy expenditure and cost were largely to very largely correlated with 5 m speed and 22 m agility sprint time and counter movement jump height (r = -0.70-0.69, p < 0.05). The detected variability indicates that global GPS-derived metabolic power data in elite soccer players from a single preseason match should be preferably used for practical applications. Contrary, high-intensity indicators should be interpreted cautiously and repeated match observations are recommended to establish meaningful high-intensity profiles of the players. Differences among playing positions and relationships with explosive physical abilities indicate that metabolic power analyses can provide new insights into the mechanics and energetics of soccer.

Large-Scale Effects of Timber Harvesting on Stream Systems in the Ouachita Mountains, Arkansas, USA

NASA Astrophysics Data System (ADS)

Williams, Lance R.; Taylor, Christopher M.; Warren, Melvin L., Jr.; Clingenpeel, J. Alan

2002-01-01

Using Basin Area Stream Survey (BASS) data from the United States Forest Service, we evaluated how timber harvesting influenced patterns of variation in physical stream features and regional fish and macroinvertebrate assemblages. Data were collected for three years (1990-1992) from six hydrologically variable streams in the Ouachita Mountains, Arkansas, USA that were paired by management regime within three drainage basins. Specifically, we used multivariate techniques to partition variability in assemblage structure (taxonomic and trophic) that could be explained by timber harvesting, drainage basin differences, year-to-year variability, and their shared variance components. Most of the variation in fish assemblages was explained by drainage basin differences, and both basin and year-of-sampling influenced macroinvertebrate assemblages. All three factors modeled, including interactions between drainage basins and timber harvesting, influenced variability in physical stream features. Interactions between timber harvesting and drainage basins indicated that differences in physical stream features were important in determining the effects of logging within a basin. The lack of a logging effect on the biota contradicts predictions for these small, hydrologically variable streams. We believe this pattern is related to the large scale of this study and the high levels of natural variability in the streams. Alternatively, there may be time-specific effects we were unable to detect with our sampling design and analyses.

Physical activity during work and leisure show contrasting associations with fear-avoidance beliefs: cross-sectional study among more than 10,000 wage earners of the general working population.

PubMed

Tribian, Annika; Vinstrup, Jonas; Sundstrup, Emil; Jay, Kenneth; Bös, Klaus; Andersen, Lars L

2018-01-26

The association between different types of physical activity and fear-avoidance beliefs remains unclear. This study investigates the association between work-related and leisure-time physical activity with fear-avoidance beliefs in the general working population. Currently employed wage earners (n=10,427) from the 2010 round of the Danish Work Environment Cohort Study replied to questions about work, lifestyle and health. General linear models controlling for lifestyle, psychosocial work factors, education, pain, medication-use and chronic diseases tested associations of work-related and leisure-time physical activity (explanatory variables) with fear-avoidance beliefs (outcome variable, scale 0-100). The level of fear-avoidance was 41.7 (SD 27.3), 38.0 (SD 26.9) and 54.3 (SD 27.7) among the general working population, a subgroup of pain-free individuals, and a subgroup with back disease, respectively. In the general working population, the level of fear-avoidance among those with low, moderate and high physical activity during leisure were 47 [95% confidence intervals (CI) 45-49], 44 (95% CI 42-46) and 43 (95% CI 41-45), and physical activity at work were 40 (95% CI 39-42), 44 (95% CI 42-46) and 49 (95% CI 48-51), respectively. Individuals with back disease and a high level of physical activity at work showed the overall highest level of fear-avoidance whereas pain-free individuals with a low level of physical activity at work showed the overall lowest level of fear-avoidance. Physical activity during work and leisure shows contrasting associations with fear-avoidance beliefs. While high physical activity during leisure is associated with lower levels, high physical activity at work is associated with higher levels of fear-avoidance. The present results may reflect some deeply rooted negative beliefs about pain and work in the population. On the societal level, campaigns may be a possible way forward as these have shown to improve beliefs about musculoskeletal pain and work.

Environmental perceptions and objective walking trail audits inform a community-based participatory research walking intervention

PubMed Central

2012-01-01

Background Given the documented physical activity disparities that exist among low-income minority communities and the increased focused on socio-ecological approaches to address physical inactivity, efforts aimed at understanding the built environment to support physical activity are needed. This community-based participatory research (CBPR) project investigates walking trails perceptions in a high minority southern community and objectively examines walking trails. The primary aim is to explore if perceived and objective audit variables predict meeting recommendations for walking and physical activity, MET/minutes/week of physical activity, and frequency of trail use. Methods A proportional sampling plan was used to survey community residents in this cross-sectional study. Previously validated instruments were pilot tested and appropriately adapted and included the short version of the validated International Physical Activity Questionnaire, trail use, and perceptions of walking trails. Walking trails were assessed using the valid and reliable Path Environmental Audit Tool which assesses four content areas including: design features, amenities, maintenance, and pedestrian safety from traffic. Analyses included Chi-square, one-way ANOVA's, multiple linear regression, and multiple logistic models. Results Numerous (n = 21) high quality walking trails were available. Across trails, there were very few indicators of incivilities and safety features rated relatively high. Among the 372 respondents, trail use significantly predicted meeting recommendations for walking and physical activity, and MET/minutes/week. While controlling for other variables, significant predictors of trail use included proximity to trails, as well as perceptions of walking trail safety, trail amenities, and neighborhood pedestrian safety. Furthermore, while controlling for education, gender, and income; for every one time per week increase in using walking trails, the odds for meeting walking recommendations increased 1.27 times, and the odds for meeting PA recommendation increased 3.54 times. Perceived and objective audit variables did not predict meeting physical activity recommendations. Conclusions To improve physical activity levels, intervention efforts are needed to maximize the use of existing trails, as well as improve residents' perceptions related to incivilities, safety, conditions of trail, and amenities of the walking trails. This study provides important insights for informing development of the CBPR walking intervention and informing local recreational and environmental policies in this southern community. PMID:22289653

Independent and combined influence of homeownership, occupation, education, income, and community poverty on physical health in persons with arthritis.

PubMed

Callahan, Leigh F; Martin, Kathryn Remmes; Shreffler, Jack; Kumar, Deepak; Schoster, Britta; Kaufman, Jay S; Schwartz, Todd A

2011-05-01

To examine the independent and combined influence of individual- and community-level socioeconomic status (SES) measures on physical health status outcomes in people with self-reported arthritis. From 2004-2005, 968 participants completed a telephone survey assessing health status, chronic conditions, community characteristics, and sociodemographic variables. Individual-level SES measures used included homeownership, occupation (professional or not), educational attainment (less than high school, high school degree, and more than high school), and income (<$15,000, $15,000-$45,000, and >$45,000). Community poverty (2000 US Census block group percentage of individuals living below the poverty line [low, medium, and high]) was used as a community-level SES measure. Outcomes were physical functioning (Medical Outcomes Study Short Form 12 version 2 physical component summary [PCS]), functional disability (Health Assessment Questionnaire [HAQ]), and the Centers for Disease Control and Prevention (CDC) Health-Related Quality of Life (HRQOL) Healthy Days physical and limited activity days, and were analyzed via multivariable regressions. When entered separately, all individual-level SES variables were significantly (P < 0.01) associated with poorer PCS, HAQ, and CDC HRQOL scores. A higher magnitude of effect was seen for household income, specifically <$15,000 per year in final models with all 4 individual SES measures and community poverty. The magnitude of effect for education is reduced and marginally significant for the PCS and number of physically unhealthy days. No effects were seen for occupation, homeownership, and community poverty. Findings confirm that after adjusting for important covariates, lower individual- and community-level SES measures are associated with poorer physical health outcomes, while household income is the strongest predictor (as measured by both significance and effect) of poorer health status in final models. Studies not having participant-reported income available should make use of other SES measures, as they do independently predict physical health. Copyright © 2011 by the American College of Rheumatology.

Physical and verbal workplace violence against nurses in Jordan.

PubMed

Al-Omari, H

2015-03-01

To explore the prevalence of physical and verbal workplace violence among nurses working in general hospitals in Jordan, and to investigate the relation between physical violence, verbal violence, anxiety about violence, and some certain demographic variables. Violence against nurses at the workplace is an alarming problem in both developed and developing countries. This study explicates physical and psychological workplace violence and its relation to anxiety about violence at workplace and to some demographic variables. A cross-sectional correlational study was conducted on a convenience sample of nurses working in general hospitals in Jordan. A total of 468 nurses completed the questionnaire, 52.8% of the participants reported that they were physically attacked, and 67.8% were verbally attacked in the last 12 months. Of those who were physically attacked, 26.5% reported a physical violence with a weapon. The logistic regression analysis revealed that female nurses were 0.5 times less likely to report being physically attacked and were 1.5 times more likely to report being verbally abused than male nurses. Violence against nurses is highly prevalent in Jordan. More than half of the participants were victims of violence at their workplace during the last year. Verbal abuse was more common among females than males. Nurses are in the frontline of the healthcare system and their safety is a high priority. They need to be involved in the development and formulation of workplace violence policy decisions. Physical and verbal workplace violence in Jordan, like other countries, is a dangerous behavior that negatively affects general hospital nurses. © 2015 International Council of Nurses.

Health behaviour models and patient preferences regarding nutrition and physical activity after breast or prostate cancer diagnosis.

PubMed

Green, H J; Steinnagel, G; Morris, C; Laakso, E L

2014-09-01

This study aimed to improve understanding of prostate and breast cancer survivors' physical activity and nutrition and the association of these behaviours with two models. The first model, the Commonsense Self-Regulation Model (CSM), addresses cognitive and emotional perceptions of illness whereas the Transtheoretical Model (TTM) focuses on stage of readiness to engage in a behaviour. Participants who had been diagnosed with either breast (n = 145) or prostate cancer (n = 92) completed measures of demographic and health information, illness representations, stage of change, self-efficacy and preferences regarding health behaviour interventions. Health behaviours in the past seven days were measured via the International Physical Activity Questionnaire and concordance with national dietary guidelines. As hypothesised, TTM variables (stage of change and self-efficacy) demonstrated independent associations with physical activity and nutrition in regression analyses. CSM variables were not independently associated with absolute levels of health behaviours but both TTM and CSM variables were independently associated with self-reported changes in physical activity and nutrition following prostate or breast cancer diagnosis. Many participants reported high interest in receiving lifestyle interventions, particularly soon after diagnosis. Results supported application of the TTM and CSM models for strengthening behaviour change intentions and actions in breast and prostate cancer survivors. © 2014 John Wiley & Sons Ltd.

Predictive factors of the nursing diagnosis sedentary lifestyle in people with high blood pressure.

PubMed

Guedes, Nirla Gomes; Lopes, Marcos Venícios de Oliveira; Araujo, Thelma Leite de; Moreira, Rafaella Pessoa; Martins, Larissa Castelo Guedes

2011-01-01

To verify the reproducibility of defining the characteristics and related factors in order to identify a sedentary lifestyle in patients with high blood pressure. A cross-sectional study. 310 patients diagnosed with high blood pressure. Socio-demographics and variables related to defining the characteristics and related factors of a sedentary lifestyle. The coefficient Kappa was utilized to analyze the reproducibility. The sensitivity, specificity, and predictive value of the defining characteristics were also analyzed. Logistic regression was applied in the analysis of possible predictors. The defining characteristic with the greatest sensitivity was demonstrates physical deconditioning (98.92%). The characteristics chooses a daily routine lacking physical exercise and verbalizes preference for activities low in physical activity presented higher values of specificity (99.21% and 95.97%, respectively). The following indicators were identified as powerful predictors (85.2%) for the identification of a sedentary lifestyle: demonstrates physical deconditioning, verbalizes preference for activities low in physical activity, and lack of training for accomplishment of physical exercise. © 2010 Wiley Periodicals, Inc.

Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study

PubMed Central

Smith, Caren E.; Arnett, Donna K.; Tsai, Michael Y.; Lai, Chao-Qiang; Parnell, Laurence D.; Shen, Jian; Laclaustra, Martin; Junyent, Mireia; Ordovás, José M.

2009-01-01

Background Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphisms in the key regulators of HDL metabolism including endothelial lipase (LIPG). Methods We examined associations between variants LIPG T111I (rs2000813) and LIPG i24582 (rs6507931), HDL and television viewing/computer use (“screen time”) as a marker for physical inactivity in a population with high prevalence of metabolic syndrome. Subjects consisted of 539 White men and 584 women (mean ± S.D., 49 ± 16 years) participating in the GOLDN study. Results We did not observe an association with either LIPG SNP or HDL independently of screen time. In multi-adjusted linear regression models, HDL interacted significantly with screen time as a continuous variable in LIPG i24582 subjects with TT genotype (P < 0.05). By dichotomizing screen time into high and low levels, we found significant genotype-associated differences in HDL in women but not men. When screen time was ≥2.6 h/day, the concentrations of total HDL-C, large HDL, large low density lipoprotein (LDL) were lower, the concentration of small LDL was higher and HDL and LDL particle sizes were smaller in subjects with LIPG i24582 TT compared to CT and CC subjects (P < 0.05). Conclusions We found a significant gene-physical inactivity interaction for HDL and some LDL measures for the LIPG i24582 polymorphism. Higher levels of physical activity may be protective for HDL-C concentrations and low activity detrimental in LIPG i24582 TT individuals, especially in women. PMID:19380136

Physical inactivity interacts with an endothelial lipase polymorphism to modulate high density lipoprotein cholesterol in the GOLDN study.

PubMed

Smith, Caren E; Arnett, Donna K; Tsai, Michael Y; Lai, Chao-Qiang; Parnell, Laurence D; Shen, Jian; Laclaustra, Martin; Junyent, Mireia; Ordovás, José M

2009-10-01

Plasma high density lipoprotein (HDL) cholesterol (HDL-C) concentration is highly heritable but is also modifiable by environmental factors including physical activity. HDL-C response to exercise varies among individuals, and this variability may be associated with genetic polymorphisms in the key regulators of HDL metabolism including endothelial lipase (LIPG). We examined associations between variants LIPG T111I (rs2000813) and LIPG i24582 (rs6507931), HDL and television viewing/computer use ("screen time") as a marker for physical inactivity in a population with high prevalence of metabolic syndrome. Subjects consisted of 539 White men and 584 women (mean+/-S.D., 49+/-16 years) participating in the GOLDN study. We did not observe an association with either LIPG SNP or HDL independently of screen time. In multi-adjusted linear regression models, HDL interacted significantly with screen time as a continuous variable in LIPG i24582 subjects with TT genotype (P<0.05). By dichotomizing screen time into high and low levels, we found significant genotype-associated differences in HDL in women but not men. When screen time was >or=2.6h/day, the concentrations of total HDL-C, large HDL, large low density lipoprotein (LDL) were lower, the concentration of small LDL was higher and HDL and LDL particle sizes were smaller in subjects with LIPG i24582 TT compared to CT and CC subjects (P<0.05). We found a significant gene-physical inactivity interaction for HDL and some LDL measures for the LIPG i24582 polymorphism. Higher levels of physical activity may be protective for HDL-C concentrations and low activity detrimental in LIPG i24582 TT individuals, especially in women.

Correlates of Injury-forced Work Reduction for Massage Therapists and Bodywork Practitioners.

PubMed

Blau, Gary; Monos, Christopher; Boyer, Ed; Davis, Kathleen; Flanagan, Richard; Lopez, Andrea; Tatum, Donna S

2013-01-01

Injury-forced work reduction (IFWR) has been acknowledged as an all-too-common occurrence for massage therapists and bodywork practitioners (M & Bs). However, little prior research has specifically investigated demographic, work attitude, and perceptual correlates of IFWR among M & Bs. To test two hypotheses, H1 and H2. H1 is that the accumulated cost variables set ( e.g., accumulated costs, continuing education costs) will account for a significant amount of IFWR variance beyond control/demographic (e.g., social desirability response bias, gender, years in practice, highest education level) and work attitude/perception variables (e.g., job satisfaction, affective occupation commitment, occupation identification, limited occupation alternatives) sets. H2 is that the two exhaustion variables (i.e., physical exhaustion, work exhaustion) set will account for significant IFWR variance beyond control/demographic, work attitude/perception, and accumulated cost variables sets. An online survey sample of 2,079 complete-data M & Bs was collected. Stepwise regression analysis was used to test the study hypotheses. The research design first controlled for control/demographic (Step1) and work attitude/perception variables sets (Step 2), before then testing for the successive incremental impact of two variable sets, accumulated costs (Step 3) and exhaustion variables (Step 4) for explaining IFWR. RESULTS SUPPORTED BOTH STUDY HYPOTHESES: accumulated cost variables set (H1) and exhaustion variables set (H2) each significantly explained IFWR after the control/demographic and work attitude/perception variables sets. The most important correlate for explaining IFWR was higher physical exhaustion, but work exhaustion was also significant. It is not just physical "wear and tear", but also "mental fatigue", that can lead to IFWR for M & Bs. Being female, having more years in practice, and having higher continuing education costs were also significant correlates of IFWR. Lower overall levels of work exhaustion, physical exhaustion, and IFWR were found in the present sample. However, since both types of exhaustion significantly and positively impact IFWR, taking sufficient time between massages and, if possible, varying one's massage technique to replenish one's physical and mental energy seem important. Failure to take required continuing education units, due to high costs, also increases risk for IFWR. Study limitations and future research issues are discussed.

Sub-regional ecosystem variability in the Canary Current upwelling

NASA Astrophysics Data System (ADS)

Arístegui, Javier; Barton, Eric D.; Álvarez-Salgado, Xosé A.; Santos, A. Miguel P.; Figueiras, Francisco G.; Kifani, Souad; Hernández-León, Santiago; Mason, Evan; Machú, Eric; Demarcq, Hervé

2009-12-01

The Canary Current upwelling ecosystem (CanC) constitutes one of the four main eastern boundary upwelling ecosystems (EBUEs) of the world, thus hosting high productivity and fisheries. Recent observations indicate that the CanC region as a whole has been experiencing a progressive warming and a decrease in productivity over the last decades. This overall trend is however not directly reflected in the fisheries of the region. Here we update recent results and previous reviews on the CanC, covering aspects from the physical environment to fish populations and fisheries on a range of time scales. We approach these topics, when possible, through a comparative exploration of the biogeographical characteristics of different sub-regions comprising this ecosystem. This review shows that variability in coastline configuration, shelf width, coastal upwelling, nutrient fertilization, productivity, or retentive vs. dispersive physical mechanisms, among other factors, may help explain sub-regional differences in fish distributions and abundances in the CanC. Nevertheless, the lack of systematic information on the regional variability of physical and biological processes hampers an integrated understanding of the relative contribution of natural vs. human-induced variability in the populations of at least small-pelagic fishes and their associated fisheries.

Making Inferences: Comprehension of Physical Causality, Intentionality, and Emotions in Discourse by High-Functioning Older Children, Adolescents, and Adults with Autism

ERIC Educational Resources Information Center

Bodner, Kimberly E.; Engelhardt, Christopher R.; Minshew, Nancy J.; Williams, Diane L.

2015-01-01

Studies investigating inferential reasoning in autism spectrum disorder (ASD) have focused on the ability to make socially-related inferences or inferences more generally. Important variables for intervention planning such as whether inferences depend on physical experiences or the nature of social information have received less consideration. A…

Effects of a 10-Week High-Intensity Exercise Intervention on College Staff with Psychological Burnout and Multiple Risk Factors

ERIC Educational Resources Information Center

Dreyer, Lukas; Dreyer, Sonja; Rankin, Dean

2012-01-01

This study examined the effect of a 10-week physical exercise program on the health status of college staff. Eighty-one participants were pre-tested on 22 variables including physical fitness, biochemical status, psychological health, and morphological measures. Participants in an experimental group (n = 61) received a 10-week intervention…

Yielding physically-interpretable emulators - A Sparse PCA approach

NASA Astrophysics Data System (ADS)

Galelli, S.; Alsahaf, A.; Giuliani, M.; Castelletti, A.

2015-12-01

Projection-based techniques, such as Principal Orthogonal Decomposition (POD), are a common approach to surrogate high-fidelity process-based models by lower order dynamic emulators. With POD, the dimensionality reduction is achieved by using observations, or 'snapshots' - generated with the high-fidelity model -, to project the entire set of input and state variables of this model onto a smaller set of basis functions that account for most of the variability in the data. While reduction efficiency and variance control of POD techniques are usually very high, the resulting emulators are structurally highly complex and can hardly be given a physically meaningful interpretation as each basis is a projection of the entire set of inputs and states. In this work, we propose a novel approach based on Sparse Principal Component Analysis (SPCA) that combines the several assets of POD methods with the potential for ex-post interpretation of the emulator structure. SPCA reduces the number of non-zero coefficients in the basis functions by identifying a sparse matrix of coefficients. While the resulting set of basis functions may retain less variance of the snapshots, the presence of a few non-zero coefficients assists in the interpretation of the underlying physical processes. The SPCA approach is tested on the reduction of a 1D hydro-ecological model (DYRESM-CAEDYM) used to describe the main ecological and hydrodynamic processes in Tono Dam, Japan. An experimental comparison against a standard POD approach shows that SPCA achieves the same accuracy in emulating a given output variable - for the same level of dimensionality reduction - while yielding better insights of the main process dynamics.

Giving birth and returning to work: the impact of work-family conflict on women's health after childbirth.

PubMed

Grice, Mira M; Feda, Denise; McGovern, Patricia; Alexander, Bruce H; McCaffrey, David; Ukestad, Laurie

2007-10-01

Since 1970, women of childbearing age have increasingly participated in the workforce. However, literature on work-family conflict has not specifically addressed the health of postpartum women. This study examined the relationship between work-family conflict and mental and physical health of employed mothers 11 weeks after childbirth. Employed women, 18 years and older, were recruited while in the hospital for childbirth (N = 817; 71% response rate). Mental and physical health at 11 weeks postpartum was measured using SF-12 version 2. General linear models estimated the associations between the independent variables and health. A priori causal models and directed acyclic graphs guided selection of confounding variables. Analyses revealed that high levels of work interference with family were associated with significantly lower mental health scores. Medium and high levels of family interference with work revealed a dose-response relationship resulting in significantly worse mental health scores. Coworker support was strongly and positively associated with better physical health. Work-family conflict was negatively associated with mental health but not significantly associated with physical health. Availability of social support may relieve the burden women can experience when balancing work roles and family obligations.

Comparison of technical and physical activities between 8 vs. 8 and 11 vs. 11 games in young Korean soccer players

PubMed Central

Oh, Seong Hwan; Joo, Chang Hwa

2018-01-01

The aims of this study were to examine the differences in technical aspects and physical demands between small-size games (SSG; 8 vs. 8) and regular-size games (RSG; 11 vs. 11) in young Korean soccer players. Seventy-nine young soccer players from 6 teams (U-12) volunteered to participate in the study. The players completed 4 games (2 SSG, 62×51 m, and 2 RSG, 80×54 m) in 2 days. Each game was filmed to evaluate technical actions. Physical demand variables were measured using global positioning system technology. SSG showed significantly greater numbers of technical plays among 17 variables when compared to RSG (P<0.05). The players covered significantly greater total distance during low−, moderate−, and high-speed running and sprinting in SSG than in RSG (P<0.05). Higher numbers of high-intensity activities (repeated high-intensity efforts, explosive efforts, decelera-tions, accelerations, and sprinting) were observed in SSG compared to RSG (P<0.05). Mean heart rate was also higher in SSG than in RSG (P<0.05). Despite the greater physical demands during SSG, the exercise intensity was similar to that reported in previous studies. Therefore, the SSG format applied in the present study can be a suitable official game format for Korean young soccer players, resulting in significantly greater exposure to technical plays without excessive physical demands. PMID:29740560

Multilevel analysis of the physical health perception of employees: community and individual factors.

PubMed

Sathyanarayanan, Sudhakar; Brooks, Ambyr J; Hagen, Susan E; Edington, Dee W

2012-01-01

To investigate whether the communities where employees reside are associated with employee perception of overall physical health after adjusting for individual factors. Retrospective cross-sectional. Active employees from a large manufacturing company representing 157 zip code tabulation areas (ZCTAs) in Michigan. 22,012 active employees who completed at least one voluntary health risk appraisal (HRA) during 1999-2001. Community deprivation and racial segregation at the ZCTA level were obtained using indices created from 2000 U.S. Census data. Demographics and HRA-related data (health-related behaviors, medical history, and quality of life indicators) at the individual level were used as independent variables. A two-level logistic regression model (employees nested in ZCTA) was used to model the probability of better self-rated health perception (SRH) (better health: 89.1% versus poor health: 10.9%). Relative to those living in highly deprived communities, employees residing in less-deprived communities showed 2.06 (95% confidence interval [CI], 1.57-2.72) and those living in moderately deprived communities showed 1.83 (95% CI, 1.42-2.35) increased odds of better SRH. After adjusting for individual-level variables, employees living in less-deprived communities had increased odds (1.31 [95% CI, 1.07-1.60]) and those living in moderately deprived communities had increased odds (1.33 [95% CI, 1.11-1.59]) of better SRH compared with individuals from highly deprived communities. The association of racial segregation with employees' SRH was mediated after adjusting for other variables. Individual-level variables showed significant statistical associations with SRH. Communities do have a modest association with SRH of the employees living there. After adjusting for individual-level and demographic variables, employees living in less/moderately deprived communities are more likely to perceive better physical health relative to those who live in highly deprived communities.

Multicollinearity in associations between multiple environmental features and body weight and abdominal fat: using matching techniques to assess whether the associations are separable.

PubMed

Leal, Cinira; Bean, Kathy; Thomas, Frédérique; Chaix, Basile

2012-06-01

Because of the strong correlations among neighborhoods' characteristics, it is not clear whether the associations of specific environmental exposures (e.g., densities of physical features and services) with obesity can be disentangled. Using data from the RECORD (Residential Environment and Coronary Heart Disease) Cohort Study (Paris, France, 2007-2008), the authors investigated whether neighborhood characteristics related to the sociodemographic, physical, service-related, and social-interactional environments were associated with body mass index and waist circumference. The authors developed an original neighborhood characteristic-matching technique (analyses within pairs of participants similarly exposed to an environmental variable) to assess whether or not these associations could be disentangled. After adjustment for individual/neighborhood socioeconomic variables, body mass index/waist circumference was negatively associated with characteristics of the physical/service environments reflecting higher densities (e.g., proportion of built surface, densities of shops selling fruits/vegetables, and restaurants). Multiple adjustment models and the neighborhood characteristic-matching technique were unable to identify which of these neighborhood variables were driving the associations because of high correlations between the environmental variables. Overall, beyond the socioeconomic environment, the physical and service environments may be associated with weight status, but it is difficult to disentangle the effects of strongly correlated environmental dimensions, even if they imply different causal mechanisms and interventions.

Learning Physics-based Models in Hydrology under the Framework of Generative Adversarial Networks

NASA Astrophysics Data System (ADS)

Karpatne, A.; Kumar, V.

2017-12-01

Generative adversarial networks (GANs), that have been highly successful in a number of applications involving large volumes of labeled and unlabeled data such as computer vision, offer huge potential for modeling the dynamics of physical processes that have been traditionally studied using simulations of physics-based models. While conventional physics-based models use labeled samples of input/output variables for model calibration (estimating the right parametric forms of relationships between variables) or data assimilation (identifying the most likely sequence of system states in dynamical systems), there is a greater opportunity to explore the full power of machine learning (ML) methods (e.g, GANs) for studying physical processes currently suffering from large knowledge gaps, e.g. ground-water flow. However, success in this endeavor requires a principled way of combining the strengths of ML methods with physics-based numerical models that are founded on a wealth of scientific knowledge. This is especially important in scientific domains like hydrology where the number of data samples is small (relative to Internet-scale applications such as image recognition where machine learning methods has found great success), and the physical relationships are complex (high-dimensional) and non-stationary. We will present a series of methods for guiding the learning of GANs using physics-based models, e.g., by using the outputs of physics-based models as input data to the generator-learner framework, and by using physics-based models as generators trained using validation data in the adversarial learning framework. These methods are being developed under the broad paradigm of theory-guided data science that we are developing to integrate scientific knowledge with data science methods for accelerating scientific discovery.

Aerobic Fitness Level Affects Cardiovascular and Salivary Alpha Amylase Responses to Acute Psychosocial Stress.

PubMed

Wyss, Thomas; Boesch, Maria; Roos, Lilian; Tschopp, Céline; Frei, Klaus M; Annen, Hubert; La Marca, Roberto

2016-12-01

Good physical fitness seems to help the individual to buffer the potential harmful impact of psychosocial stress on somatic and mental health. The aim of the present study is to investigate the role of physical fitness levels on the autonomic nervous system (ANS; i.e. heart rate and salivary alpha amylase) responses to acute psychosocial stress, while controlling for established factors influencing individual stress reactions. The Trier Social Stress Test for Groups (TSST-G) was executed with 302 male recruits during their first week of Swiss Army basic training. Heart rate was measured continuously, and salivary alpha amylase was measured twice, before and after the stress intervention. In the same week, all volunteers participated in a physical fitness test and they responded to questionnaires on lifestyle factors and personal traits. A multiple linear regression analysis was conducted to determine ANS responses to acute psychosocial stress from physical fitness test performances, controlling for personal traits, behavioural factors, and socioeconomic data. Multiple linear regression revealed three variables predicting 15 % of the variance in heart rate response (area under the individual heart rate response curve during TSST-G) and four variables predicting 12 % of the variance in salivary alpha amylase response (salivary alpha amylase level immediately after the TSST-G) to acute psychosocial stress. A strong performance at the progressive endurance run (high maximal oxygen consumption) was a significant predictor of ANS response in both models: low area under the heart rate response curve during TSST-G as well as low salivary alpha amylase level after TSST-G. Further, high muscle power, non-smoking, high extraversion, and low agreeableness were predictors of a favourable ANS response in either one of the two dependent variables. Good physical fitness, especially good aerobic endurance capacity, is an important protective factor against health-threatening reactions to acute psychosocial stress.

Relationships among selected physical science misconceptions held by preservice elementary teachers and four variables: Formal reasoning ability, working memory capacity, verbal intelligence, and field dependence/independence

NASA Astrophysics Data System (ADS)

Griffin, Leslie Little

The purpose of this study was to determine the relationship of selected cognitive abilities and physical science misconceptions held by preservice elementary teachers. The cognitive abilities under investigation were: formal reasoning ability as measured by the Lawson Classroom Test of Formal Reasoning (Lawson, 1978); working memory capacity as measured by the Figural Intersection Test (Burtis & Pascual-Leone, 1974); verbal intelligence as measured by the Acorn National Academic Aptitude Test: Verbal Intelligence (Kobal, Wrightstone, & Kunze, 1944); and field dependence/independence as measured by the Group Embedded Figures Test (Witkin, Oltman, & Raskin, 1971). The number of physical science misconceptions held by preservice elementary teachers was measured by the Misconceptions in Science Questionnaire (Franklin, 1992). The data utilized in this investigation were obtained from 36 preservice elementary teachers enrolled in two sections of a science methods course at a small regional university in the southeastern United States. Multiple regression techniques were used to analyze the collected data. The following conclusions were reached following an analysis of the data. The variables of formal reasoning ability and verbal intelligence were identified as having significant relationships, both individually and in combination, to the dependent variable of selected physical science misconceptions. Though the correlations were not high enough to yield strong predictors of physical science misconceptions or strong relationships, they were of sufficient magnitude to warrant further investigation. It is recommended that further investigation be conducted replicating this study with a larger sample size. In addition, experimental research should be implemented to explore the relationships suggested in this study between the cognitive variables of formal reasoning ability and verbal intelligence and the dependent variable of selected physical science misconceptions. Further research should also focus on the detection of a broad range of science misconceptions among preservice elementary teachers.

Long-Term Monitoring of Physical Behavior Reveals Different Cardiac Responses to Physical Activity among Subjects with and without Chronic Neck Pain.

PubMed

Hallman, David M; Mathiassen, Svend Erik; Lyskov, Eugene

2015-01-01

We determined the extent to which heart rate variability (HRV) responses to daily physical activity differ between subjects with and without chronic neck pain. Twenty-nine subjects (13 women) with chronic neck pain and 27 age- and gender-matched healthy controls participated. Physical activity (accelerometry), HRV (heart rate monitor), and spatial location (Global Positioning System (GPS)) were recorded for 74 hours. GPS data were combined with a diary to identify periods of work and of leisure at home and elsewhere. Time- and frequency-domain HRV indices were calculated and stratified by period and activity type (lying/sitting, standing, or walking). ANCOVAs with multiple adjustments were used to disclose possible group differences in HRV. The pain group showed a reduced HRV response to physical activity compared with controls (p = .001), according to the sympathetic-baroreceptor HRV index (LF/HF, ratio between low- and high-frequency power), even after adjustment for leisure time physical activity, work stress, sleep quality, mental health, and aerobic capacity (p = .02). The parasympathetic response to physical activity did not differ between groups. Relying on long-term monitoring of physical behavior and heart rate variability, we found an aberrant sympathetic-baroreceptor response to daily physical activity among subjects with chronic neck pain.

Social inequality in physical and mental health comorbidity dynamics.

PubMed

Sacker, Amanda; Head, Jenny; Gimeno, David; Bartley, Mel

2009-09-01

To examine how socioeconomic position influences physical and mental health dynamics. The Whitehall II study of civil servants collected questionnaires on six occasions from 1991/93 to 2006/07. Civil service grade measured socioeconomic position and Short Form 36 General Health Survey component scores rated physical and mental health. Bivariate growth curve models of physical and mental health over 15 years were estimated for high, medium, and low grades (n = 8309). At baseline, levels of physical and mental health were correlated for participants in low grades only. Among study participants in medium grades, mental health was maintained over time, even as physical health decreased. Restoring mental health after a negative response to poor physical health was more difficult for some in low grades. Recovery from downturns in physical health associated with poorer mental health also depended on better socioeconomic circumstances There was greater variability in baseline levels and rates of change in the mental and physical health of those in lower grades compared with higher grades. Homeostatic mechanisms may vary by socioeconomic position. The greater variability of change in health function for those in lower grades implies considerable scope for improvement if sources of variation in health within disadvantaged groups that are amenable to intervention can be identified.

Insufficient free-time physical activity and occupational factors in Brazilian public school teachers

PubMed Central

Dias, Douglas Fernando; Loch, Mathias Roberto; González, Alberto Durán; de Andrade, Selma Maffei; Mesas, Arthur Eumann

2017-01-01

ABSTRACT OBJECTIVE To evaluate if perceived occupational factors are associated with insufficient free-time physical activity in Brazilian public school teachers. METHODS The relationship between insufficient physical activity (< 150 minutes/week) and variables related to work was analyzed in 978 elementary and high school teachers calculating the prevalence ratio (PR) and 95% confidence interval (95%CI) in Poisson regression models, adjusted for sociodemographic and health variables. RESULTS The prevalence of insufficient physical activity was 71.9%, and this condition was associated independently with the perception of bad or regular balance between personal and professional life (PR = 1.09; 95%CI 1.01–1.18), perception that standing time affects the work (PR = 1.16; 95%CI 1.01–1.34), low or very low perception of current ability for the physical requirements of work (PR = 1.21; 95%CI 1.08–1.35), and temporary employment contract (PR = 1.13; 95%CI 1.03–1.25). The teaching of physical education was associated with lower prevalence of insufficient physical activity (PR = 0.78; 95%CI 0.64–0.95). CONCLUSIONS The perception of adverse working conditions is associated with increased prevalence of insufficient physical activity in teachers and should be considered for the promotion of physical activity in this population. PMID:28746571

Psychological distress among Norwegian adolescents: Changes between 2001 and 2009 and associations with leisure time physical activity and screen-based sedentary behaviour.

PubMed

Kleppang, Annette Løvheim; Thurston, Miranda; Hartz, Ingeborg; Hagquist, Curt

2017-06-01

The aim of this work was to examine psychological distress among Norwegian adolescents in relation to changes over time and the associations with leisure time physical activity and screen-based sedentary behaviour. This cross-sectional study was based on data retrieved from the Norwegian Youth Health Surveys in 2001 and 2009 in Hedmark County. Adolescents aged 15-16 years old completed a questionnaire regarding physical activity, sedentary behaviour, psychological distress and other health and lifestyle variables. The self-report Hopkins Symptom Checklist-10 was used to assess psychological distress. Multinomial logistic regression was used to analyse the associations between psychological distress, physical activity and sedentary behaviour. Self-reported psychological distress increased significantly from 2001 to 2009 (from 19.4 to 28.2%), with the proportion of girls reporting psychological distress being twice as large as the proportion of boys. The proportion of adolescents who were physically active for ⩾11 hours per week increased significantly over the same period (from 6.0 to 10.4%). Sedentary behaviour ⩾6 hours per school day increased significantly among both sexes between 2001 and 2009. Physical activity (⩾11 hours) and sedentary behaviour (⩾6 hours) were both significantly associated with psychological distress. The association between physical activity, sedentary behaviour and psychological distress was weak; only high amounts of physical activity and high amounts of screen-based sedentary behaviour were associated with psychological distress. Longitudinal studies are needed to provide further insights into these associations and to understand the extent to which these variables might be causally related.

Patterns of Health-Risk Behavior among Japanese High School Students.

ERIC Educational Resources Information Center

Takakura, Minoru; Nagayama, Tomoko; Sakihara, Seizo; Willcox, Craig

2001-01-01

Surveyed Japanese high school students' health risk behavior patterns, examining clustering and accumulation of health risk behaviors. Physical inactivity and alcohol use were the most common risk behaviors. Prevalence rates for most risk behaviors varied by demographic variables. Smoking, drinking, and sexual intercourse clustered among both…

Habitual physical activity and plasma metabolomic patterns distinguish individuals with low vs. high weight loss during controlled energy restriction.

PubMed

Piccolo, Brian D; Keim, Nancy L; Fiehn, Oliver; Adams, Sean H; Van Loan, Marta D; Newman, John W

2015-04-01

Total weight loss induced by energy restriction is highly variable even under tightly controlled conditions. Identifying weight-loss discriminants would provide a valuable weight management tool and insights into body weight regulation. This study characterized responsiveness to energy restriction in adults from variables including the plasma metabolome, endocrine and inflammatory markers, clinical indices, body composition, diet, and physical activity. Data were derived from a controlled feeding trial investigating the effect of 3-4 dairy product servings in an energy-restricted diet (2092 kJ/d reduction) over 12 wk. Partial least squares regression was used to identify weight-loss discriminants in 67 overweight and obese adults. Linear mixed models were developed to identify discriminant variable differences in high- vs. low-weight-loss responders. Both pre- and postintervention variables (n = 127) were identified as weight-loss discriminants (root mean squared error of prediction = 1.85 kg; Q(2) = 0.43). Compared with low-responders (LR), high-responders (HR) had greater decreases in body weight (LR: 2.7 ± 1.6 kg; HR: 9.4 ± 1.8 kg, P < 0.01), BMI (in kg/m(2); LR: 1.0 ± 0.6; HR: 3.3 ± 0.5, P < 0.01), and total fat (LR: 2.2 ± 1.1 kg; HR: 8.0 ± 2.1 kg, P < 0.01). Significant group effects unaffected by the intervention were determined for the respiratory exchange ratio (LR: 0.86 ± 0.05; HR: 0.82 ± 0.03, P < 0.01), moderate physical activity (LR: 127 ± 52 min; HR: 167 ± 68 min, P = 0.02), sedentary activity (LR: 1090 ± 99 min; HR: 1017 ± 110 min, P = 0.02), and plasma stearate [LR: 102,000 ± 21,000 quantifier ion peak height (QIPH); HR: 116,000 ± 24,000 QIPH, P = 0.01]. Overweight and obese individuals highly responsive to energy restriction had accelerated reductions in adiposity, likely supported in part by higher lipid mobilization and combustion. A novel observation was that person-to-person differences in habitual physical activity and magnitude of weight loss were accompanied by unique blood metabolite signatures. This trial was registered at clinicaltrials.gov as NCT00858312. © 2015 American Society for Nutrition.

Insights on multivariate updates of physical and biogeochemical ocean variables using an Ensemble Kalman Filter and an idealized model of upwelling

NASA Astrophysics Data System (ADS)

Yu, Liuqian; Fennel, Katja; Bertino, Laurent; Gharamti, Mohamad El; Thompson, Keith R.

2018-06-01

Effective data assimilation methods for incorporating observations into marine biogeochemical models are required to improve hindcasts, nowcasts and forecasts of the ocean's biogeochemical state. Recent assimilation efforts have shown that updating model physics alone can degrade biogeochemical fields while only updating biogeochemical variables may not improve a model's predictive skill when the physical fields are inaccurate. Here we systematically investigate whether multivariate updates of physical and biogeochemical model states are superior to only updating either physical or biogeochemical variables. We conducted a series of twin experiments in an idealized ocean channel that experiences wind-driven upwelling. The forecast model was forced with biased wind stress and perturbed biogeochemical model parameters compared to the model run representing the "truth". Taking advantage of the multivariate nature of the deterministic Ensemble Kalman Filter (DEnKF), we assimilated different combinations of synthetic physical (sea surface height, sea surface temperature and temperature profiles) and biogeochemical (surface chlorophyll and nitrate profiles) observations. We show that when biogeochemical and physical properties are highly correlated (e.g., thermocline and nutricline), multivariate updates of both are essential for improving model skill and can be accomplished by assimilating either physical (e.g., temperature profiles) or biogeochemical (e.g., nutrient profiles) observations. In our idealized domain, the improvement is largely due to a better representation of nutrient upwelling, which results in a more accurate nutrient input into the euphotic zone. In contrast, assimilating surface chlorophyll improves the model state only slightly, because surface chlorophyll contains little information about the vertical density structure. We also show that a degradation of the correlation between observed subsurface temperature and nutrient fields, which has been an issue in several previous assimilation studies, can be reduced by multivariate updates of physical and biogeochemical fields.

Detecting Habitats and Ecosystem Functions Considering the Mesozooplankton Size and Diversity Structures and Environmental Conditions in the Gulf of Lion, NW Mediterranean Sea

NASA Astrophysics Data System (ADS)

Carlotti, F.; Espinasse, B.; Zhou, M.; Jean-Luc, D.

2016-02-01

Environmental conditions and zooplankton size structure and taxonomic diversity were investigated in the Gulf of Lion in May 2010 and January 2011. The integrated physical and biological measurements provided a 3D view with high spatial resolution of the physical and biological variables and their correlations over the whole gulf. The effects of physical processes such as freshwater input, coastal upwelling, and water column mixing by winds on phytoplankton and zooplankton distributions were analyzed using these data. Several analytic tests were performed in order to define several ecoregions representing different habitats of plankton communities. Three habitats were distinguished based on statistical analysis performed on biological and physical variables: (1) the coastal area characterized by shallow waters, high chl a concentrations, and a steep slope of the normalized biomass size spectrum (NBSS); (2) the area affected by the Rhône with high stratification and flat NBSS slope; and (3) the continental shelf with a deep mixed layer, relatively low particle concentrations, and moderate NBSS slope. The zooplankton diversity was characterized by spatial differences in community composition among the Rhône plume area, the coastal shelf, and shelf break waters. Defining habitat is a relevant approach to designing new zooplankton sampling strategies, validating distribution models and including the zooplankton compartment in trophodynamic studies.

Genetic variability in Jatropha curcas L. from diallel crossing.

PubMed

Ribeiro, D O; Silva-Mann, R; Alvares-Carvalho, S V; Souza, E M S; Vasconcelos, M C; Blank, A F

2017-05-18

Physic nut (Jatropha curcas L.) presents high oilseed yield and low production cost. However, technical-scientific knowledge on this crop is still limited. This study aimed to evaluate and estimate the genetic variability of hybrids obtained from dialell crossing. Genetic variability was carried out using ISSR molecular markers. For genetic variability, nine primers were used, and six were selected with 80.7% polymorphism. Genetic similarity was obtained using the NTSYS pc. 2.1 software, and cluster analysis was obtained by the UPGMA method. Mean genetic similarity was 58.4% among hybrids; the most divergent pair was H1 and H10 and the most similar pair was H9 and H10. ISSR PCR markers provided a quick and highly informative system for DNA fingerprinting, and also allowed establishing genetic relationships of Jatropha hybrids.

Physical Activity Levels and Well-Being in Older Adults.

PubMed

Bae, Wonyul; Ik Suh, Young; Ryu, Jungsu; Heo, Jinmoo

2017-04-01

The objective of this study was to identify the interconnectedness of different intensity levels of physical activity and psychological (life satisfaction and positive affect) and physical (physical health) well-being. Participants were from the National Study of Midlife in the United States with assessments in 2004 and aged 25 to 74 living in the United States were included in the analyses. We conducted bivariate correlations to examine significant relationships among the study variables. In addition, after multicollinearity among the independent variable was checked, a series of hierarchical regression analyses with physical health, positive affect, and life satisfaction as criterion variables were conducted. The results showed that light physical activities were positively associated with physical health and life satisfaction in summer, whereas light physical activities and all dependent variables were positively correlated in winter. Furthermore, engaging in moderate physical activities was positively related only with physical health. Meanwhile, vigorous physical activities were not associated with life satisfaction, physical health, and positive affect in summer and winter.

High intralocus variability and interlocus recombination promote immunological diversity in a minimal major histocompatibility system.

PubMed

Wilson, Anthony B; Whittington, Camilla M; Bahr, Angela

2014-12-20

The genes of the major histocompatibility complex (MHC/MH) have attracted considerable scientific interest due to their exceptional levels of variability and important function as part of the adaptive immune system. Despite a large number of studies on MH class II diversity of both model and non-model organisms, most research has focused on patterns of genetic variability at individual loci, failing to capture the functional diversity of the biologically active dimeric molecule. Here, we take a systematic approach to the study of MH variation, analyzing patterns of genetic variation at MH class IIα and IIβ loci of the seahorse, which together form the immunologically active peptide binding cleft of the MH class II molecule. The seahorse carries a minimal class II system, consisting of single copies of both MH class IIα and IIβ, which are physically linked and inherited in a Mendelian fashion. Both genes are ubiquitously expressed and detectible in the brood pouch of male seahorses throughout pregnancy. Genetic variability of the two genes is high, dominated by non-synonymous variation concentrated in their peptide-binding regions. Coding variation outside these regions is negligible, a pattern thought to be driven by intra- and interlocus recombination. Despite the tight physical linkage of MH IIα and IIβ loci, recombination has produced novel composite alleles, increasing functional diversity at sites responsible for antigen recognition. Antigen recognition by the adaptive immune system of the seahorse is enhanced by high variability at both MH class IIα and IIβ loci. Strong positive selection on sites involved in pathogen recognition, coupled with high levels of intra- and interlocus recombination, produce a patchwork pattern of genetic variation driven by genetic hitchhiking. Studies focusing on variation at individual MH loci may unintentionally overlook an important component of ecologically relevant variation.

Perception of built environmental factors and physical activity among adolescents in Nigeria

PubMed Central

2014-01-01

Background Understanding environmental factors related to adolescents’ physical activity can inform intervention for obesity control and prevention, but virtually no study has been conducted in the African region, where adolescents’ physical inactivity and chronic diseases rates are rising. This study assessed associations between perceived built environmental variables and adolescents’ physical activity (active transportation to school and leisure-time moderate-to- vigorous physical activity), and the moderating effects of neighborhood-level income on association between environmental variables and physical activity among Nigerian boys and girls. Methods Participants were 1006 adolescents (12–19 years, 50.4% girls) randomly selected from 11 secondary schools in Maiduguri city, Nigeria. Physical activity and perceptions of environmental characteristics were assessed by validated self-report questionnaires. Separate gender-based, hierarchical multiple moderated linear regression analyses were used to examine the direct associations between the environmental perceptions and physical activity variables (active transportation and leisure-time MVPA; dependent variables), as well as the moderating effects of neighborhood-level income. Results Only in boys were direct associations and interaction effect of neighborhood-level income found. Access to destinations was positively associated with active transportation to school (β = 0.18; CI = 0.67, 2.24); while residential density (β = 0.10; CI = 0.01, 1.74) and availability/quality of infrastructures (β = 0.14; CI = 0.49, 2.68) were positively associated with leisure-time MVPA. Also, neighborhood-level income moderated the association between perceived safety and leisure-time MVPA, with more perceived safety related to less MVPA (β = -0.16; CI = -0.01, -0.70) in boys living in high SES neighborhood but marginally related to more MVPA (β = 0.11; CI = -0.04, 2.88, p = 0.06) in boys living in low SES neighborhood. Conclusions Few environmental attributes were associated with adolescents’ physical activity in Nigeria. Future studies are needed to determine the multidimensional correlates of physical activity that may be relevant for both adolescents’ boys and girls in Nigeria. PMID:24766710

High school students' scientific epistemological beliefs, self-efficacy in learning physics and attitudes toward physics: a structural equation model

NASA Astrophysics Data System (ADS)

Kapucu, Serkan; Bahçivan, Eralp

2015-05-01

Background: There are some theoretical evidences that explain the relationships between core beliefs (i.e., epistemological beliefs) and peripheral beliefs (self-efficacy in learning) in the literature. The close relationships of such type of beliefs with attitudes are also discussed by some researchers. Constructing a model that investigates these relationships by considering theoretical and empirical evidences can empower researchers to discuss these relationships more comprehensively. Purpose: The purpose of this study is to explore the relationships among Turkish high school students' scientific epistemological beliefs, self-efficacy in learning physics and their attitudes toward physics. Sample: A total of 632 high school students participated in this study; however, 269 female and 229 male (a total of 498) high school students' data were used. Design and methods: Three distinct instruments that measure scientific epistemological beliefs, self-efficacy in learning physics and attitudes toward physics were combined into a unique questionnaire form and it was distributed to high school students. To explore the relationships among these variables, structural equation modeling was used. Results: The results showed that scientific epistemological belief dimensions uncovered by the nature of knowing (source and justification) significantly and positively related to both self-efficacy in learning physics and attitudes toward other important physics dimensions. Additionally, self-efficacy in learning physics significantly and positively predicted attitudes toward multiple physics dimensions (importance, comprehension and requirement). However, epistemological belief dimensions related to the nature of knowledge (certainty and development) did not have significant impact on self-efficacy in learning physics or attitudes toward physics. Conclusions: This study concludes that there are positive and significant relationships among Turkish high school students' scientific epistemological beliefs, self-efficacy in learning physics and their attitudes toward physics.

Understanding extreme quasar optical variability with CRTS - I. Major AGN flares

NASA Astrophysics Data System (ADS)

Graham, Matthew J.; Djorgovski, S. G.; Drake, Andrew J.; Stern, Daniel; Mahabal, Ashish A.; Glikman, Eilat; Larson, Steve; Christensen, Eric

2017-10-01

There is a large degree of variety in the optical variability of quasars and it is unclear whether this is all attributable to a single (set of) physical mechanism(s). We present the results of a systematic search for major flares in active galactic nucleus (AGN) in the Catalina Real-time Transient Survey as part of a broader study into extreme quasar variability. Such flares are defined in a quantitative manner as being atop of the normal, stochastic variability of quasars. We have identified 51 events from over 900 000 known quasars and high-probability quasar candidates, typically lasting 900 d and with a median peak amplitude of Δm = 1.25 mag. Characterizing the flare profile with a Weibull distribution, we find that nine of the sources are well described by a single-point single-lens model. This supports the proposal by Lawrence et al. that microlensing is a plausible physical mechanism for extreme variability. However, we attribute the majority of our events to explosive stellar-related activity in the accretion disc: superluminous supernovae, tidal disruption events and mergers of stellar mass black holes.

AGN Variability: Probing Black Hole Accretion

NASA Astrophysics Data System (ADS)

Moreno, Jackeline; O'Brien, Jack; Vogeley, Michael S.; Richards, Gordon T.; Kasliwal, Vishal P.

2017-01-01

We combine the long temporal baseline of Sloan Digital Sky Survey (SDSS) for quasars in Stripe 82 with the high precision photometry of the Kepler/K2 Satellite to study the physics of optical variability in the accretion disk and supermassive black hole engine. We model the lightcurves directly as Continuous-time Auto Regressive Moving Average processes (C-ARMA) with the Kali analysis package (Kasliwal et al. 2016). These models are extremely robust to irregular sampling and can capture aperiodic variability structure on various timescales. We also estimate the power spectral density and structure function of both the model family and the data. A Green's function kernel may also be estimated for the resulting C-ARMA parameter fit, which may be interpreted as the response to driving impulses such as hotspots in the accretion disk. We also examine available spectra for our AGN sample to relate observed and modelled behavior to spectral properties. The objective of this work is twofold: to explore the proper physical interpretation of different families of C-ARMA models applied to AGN optical flux variability and to relate empirical characteristic timescales of our AGN sample to physical theory or to properties estimated from spectra or simulations like the disk viscosity and temperature. We find that AGN with strong variability features on timescales resolved by K2 are well modelled by a low order C-ARMA family while K2 lightcurves with weak amplitude variability are dominated by outliers and measurement errors which force higher order model fits. This work explores a novel approach to combining SDSS and K2 data sets and presents recovered characteristic timescales of AGN variability.

Is the relationship between the built environment and physical activity moderated by perceptions of crime and safety?

PubMed

Bracy, Nicole L; Millstein, Rachel A; Carlson, Jordan A; Conway, Terry L; Sallis, James F; Saelens, Brian E; Kerr, Jacqueline; Cain, Kelli L; Frank, Lawrence D; King, Abby C

2014-02-24

Direct relationships between safety concerns and physical activity have been inconsistently patterned in the literature. To tease out these relationships, crime, pedestrian, and traffic safety were examined as moderators of built environment associations with physical activity. Exploratory analyses used two cross-sectional studies of 2068 adults ages 20-65 and 718 seniors ages 66+ with similar designs and measures. The studies were conducted in the Baltimore, Maryland-Washington, DC and Seattle-King County, Washington regions during 2001-2005 (adults) and 2005-2008 (seniors). Participants were recruited from areas selected to sample high- and low- income and walkability. Independent variables perceived crime, traffic, and pedestrian safety were measured using scales from validated instruments. A GIS-based walkability index was calculated for a street-network buffer around each participant's home address. Outcomes were total physical activity measured using accelerometers and transportation and leisure walking measured with validated self-reports (IPAQ-long). Mixed effects regression models were conducted separately for each sample. Of 36 interactions evaluated across both studies, only 5 were significant (p< .05). Significant interactions did not consistently support a pattern of highest physical activity when safety was rated high and environments were favorable. There was not consistent evidence that safety concerns reduced the beneficial effects of favorable environments on physical activity. Only pedestrian safety showed evidence of a consistent main effect with physical activity outcomes, possibly because pedestrian safety items (e.g., crosswalks, sidewalks) were not as subjective as those on the crime and traffic safety scales. Clear relationships between crime, pedestrian, and traffic safety with physical activity levels remain elusive. The development of more precise safety variables and the use of neighborhood-specific physical activity outcomes may help to elucidate these relationships.

Is the relationship between the built environment and physical activity moderated by perceptions of crime and safety?

PubMed Central

2014-01-01

Background Direct relationships between safety concerns and physical activity have been inconsistently patterned in the literature. To tease out these relationships, crime, pedestrian, and traffic safety were examined as moderators of built environment associations with physical activity. Methods Exploratory analyses used two cross-sectional studies of 2068 adults ages 20–65 and 718 seniors ages 66+ with similar designs and measures. The studies were conducted in the Baltimore, Maryland-Washington, DC and Seattle-King County, Washington regions during 2001–2005 (adults) and 2005–2008 (seniors). Participants were recruited from areas selected to sample high- and low- income and walkability. Independent variables perceived crime, traffic, and pedestrian safety were measured using scales from validated instruments. A GIS-based walkability index was calculated for a street-network buffer around each participant’s home address. Outcomes were total physical activity measured using accelerometers and transportation and leisure walking measured with validated self-reports (IPAQ-long). Mixed effects regression models were conducted separately for each sample. Results Of 36 interactions evaluated across both studies, only 5 were significant (p < .05). Significant interactions did not consistently support a pattern of highest physical activity when safety was rated high and environments were favorable. There was not consistent evidence that safety concerns reduced the beneficial effects of favorable environments on physical activity. Only pedestrian safety showed evidence of a consistent main effect with physical activity outcomes, possibly because pedestrian safety items (e.g., crosswalks, sidewalks) were not as subjective as those on the crime and traffic safety scales. Conclusions Clear relationships between crime, pedestrian, and traffic safety with physical activity levels remain elusive. The development of more precise safety variables and the use of neighborhood-specific physical activity outcomes may help to elucidate these relationships. PMID:24564971

A physics-based probabilistic forecasting model for rainfall-induced shallow landslides at regional scale

NASA Astrophysics Data System (ADS)

Zhang, Shaojie; Zhao, Luqiang; Delgado-Tellez, Ricardo; Bao, Hongjun

2018-03-01

Conventional outputs of physics-based landslide forecasting models are presented as deterministic warnings by calculating the safety factor (Fs) of potentially dangerous slopes. However, these models are highly dependent on variables such as cohesion force and internal friction angle which are affected by a high degree of uncertainty especially at a regional scale, resulting in unacceptable uncertainties of Fs. Under such circumstances, the outputs of physical models are more suitable if presented in the form of landslide probability values. In order to develop such models, a method to link the uncertainty of soil parameter values with landslide probability is devised. This paper proposes the use of Monte Carlo methods to quantitatively express uncertainty by assigning random values to physical variables inside a defined interval. The inequality Fs < 1 is tested for each pixel in n simulations which are integrated in a unique parameter. This parameter links the landslide probability to the uncertainties of soil mechanical parameters and is used to create a physics-based probabilistic forecasting model for rainfall-induced shallow landslides. The prediction ability of this model was tested in a case study, in which simulated forecasting of landslide disasters associated with heavy rainfalls on 9 July 2013 in the Wenchuan earthquake region of Sichuan province, China, was performed. The proposed model successfully forecasted landslides in 159 of the 176 disaster points registered by the geo-environmental monitoring station of Sichuan province. Such testing results indicate that the new model can be operated in a highly efficient way and show more reliable results, attributable to its high prediction accuracy. Accordingly, the new model can be potentially packaged into a forecasting system for shallow landslides providing technological support for the mitigation of these disasters at regional scale.

Association of physical inactivity with hypertension and low educational level in people living with HIV / AIDS.

PubMed

Silveira, Erika Aparecida; Santos, Annelisa Silva E Alves de Carvalho; Falco, Marianne de Oliveira; Cardoso, Rodrigo de Castro; Vitorino, Priscila Valverde de Oliveira

2018-08-01

The aim of this study was to determine the prevalence of physical inactivity and whether it is associated with sociodemographic, lifestyle, clinical, anthropometric, and body composition variables in people living with HIV/AIDS (PLWHA). This study makes use of data from a cohort of 288 adults aged ≥19 years, conducted between October 2009 and July 2011. The variables studied were sex, age, education, income, skin color, tobacco use, alcohol intake, body mass index, body fat percentage, waist circumference, and waist-hip ratio, length of HIV/AIDS diagnosis, use of antiretroviral therapy and length of its use, CD4, hypertension (HT) and diabetes mellitus. Physical inactivity was defined as a score below 600 metabolic equivalent minutes/week according to the International Physical Activity Questionnaire - Short Version. Poisson multiple regression was applied in the multivariate analysis with a significance level of 5%. The prevalence of physical inactivity was 44.1%. Education of ≤4 years of study (prevalence ratio [PR]: 1.71) and HT (PR: 1.49) were associated with physical inactivity. Physical inactivity was highly prevalent in PLWHA and associated with low educational level and HT. We highlight the simultaneous association between two cardiometabolic risk factors, HT and physical inactivity.

Determining the spatial variability of crop yields of two different climatic regions in Southwest Germany

NASA Astrophysics Data System (ADS)

Eshonkulov, Ravshan; Poyda, Arne; Ingwersen, Joachim; Streck, Thilo

2017-04-01

Assessing the spatial variability of soil physical properties is crucial for agricultural land management. We determined the spatial variability within two agricultural fields in the regions of Kraichgau and Swabian Jura in Southwest Germany. We determined soil physical properties and recorded the temporal development of soil mineral nitrogen (N) and water content as well as that of plant variables (phenology, biomass, leaf area index (LAI), N content, green vegetation fraction (GVF). The work was conducted during the vegetation periods of 2015 and 2016 in winter wheat, and winter rapeseed in Kraichgau and winter barley and silage maize on Swabian Jura. Measurements were taken in three-weekly intervals. On each field, we identified three plots with reduced plant development using high-resolution (RapidEye) satellite images ("cold spots"). Measurements taken on these cold spots were compared to those from five established (long-term) reference plots representing the average field variability. The software EXPERT-N was used to simulate the soil crop system at both cold spots and reference plots. Sensitivity analyses were conducted to identify the most important parameters for the determination of spatial variability in crop growth dynamics.

Physical attraction to reliable, low variability nervous systems: Reaction time variability predicts attractiveness.

PubMed

Butler, Emily E; Saville, Christopher W N; Ward, Robert; Ramsey, Richard

2017-01-01

The human face cues a range of important fitness information, which guides mate selection towards desirable others. Given humans' high investment in the central nervous system (CNS), cues to CNS function should be especially important in social selection. We tested if facial attractiveness preferences are sensitive to the reliability of human nervous system function. Several decades of research suggest an operational measure for CNS reliability is reaction time variability, which is measured by standard deviation of reaction times across trials. Across two experiments, we show that low reaction time variability is associated with facial attractiveness. Moreover, variability in performance made a unique contribution to attractiveness judgements above and beyond both physical health and sex-typicality judgements, which have previously been associated with perceptions of attractiveness. In a third experiment, we empirically estimated the distribution of attractiveness preferences expected by chance and show that the size and direction of our results in Experiments 1 and 2 are statistically unlikely without reference to reaction time variability. We conclude that an operating characteristic of the human nervous system, reliability of information processing, is signalled to others through facial appearance. Copyright © 2016 Elsevier B.V. All rights reserved.

Exploring physical exposures and identifying high-risk work tasks within the floor layer trade

PubMed Central

McGaha, Jamie; Miller, Kim; Descatha, Alexis; Welch, Laurie; Buchholz, Bryan; Evanoff, Bradley; Dale, Ann Marie

2014-01-01

Introduction Floor layers have high rates of musculoskeletal disorders yet few studies have examined their work exposures. This study used observational methods to describe physical exposures within floor laying tasks. Methods We analyzed 45 videos from 32 floor layers using Multimedia-Video Task Analysis software to determine the time in task, forces, postures, and repetitive hand movements for installation of four common flooring materials. We used the WISHA checklists to define exposure thresholds. Results Most workers (91%) met the caution threshold for one or more exposures. Workers showed high exposures in multiple body parts with variability in exposures across tasks and for different materials. Prolonged exposures were seen for kneeling, poor neck and low back postures, and intermittent but frequent hand grip forces. Conclusions Floor layers experience prolonged awkward postures and high force physical exposures in multiple body parts, which probably contribute to their high rates of musculoskeletal disorders. PMID:24274895

[Positive effects of physical exercise on reducing the relationship between subcutaneous abdominal fat and morbility risk].

PubMed

González Calvo, G; Hernández Sánchez, S; Pozo Rosado, P; García López, D

2011-01-01

The consequences related to the accumulation of abdominal fat above healthy levels create a considerable organic damage. Among the physiological consequences we can highlight heart diseases, hypertension, type-2 diabetes, obesity and metabolic syndrome, which drastically reduce life expectancy and quality. Evidence shows that health improvement is correlated to greater levels of physical activity. However, physical exercise can create oxidative damage on organs and muscular tissue, more relevant in subjects with a high percentage of abdominal fat. This piece of work determines which are the fundamental variables of the exercise program in order to optimize its advantages while minimizing oxidative stress. To know the key variables in the accumulation of abdominal fat above healthy levels, and the role of exercise in prevention and improvement of such issue. SPECIFIC PURPOSES: 1) to identify the key variables in an exercise program aimed at reducing abdominal fat; 2) to understand the relationship between abdominal fat, health and exercise; 3) to review the latest research related to physical exercise and its effect on abdominal adipose tissue. A search and identification of original and reviewed articles will be carried out in indexed impact journals within the main databases. Regular physical exercise, most notably aerobic one, reduces body adipose tissue deposits in general, and abdominal ones in particular, both in obese and overweight subjects.

Predicting Scientific Understanding of Prospective Elementary Teachers: Role of Gender, Education Level, Courses in Science, and Attitudes Toward Science and Mathematics

NASA Astrophysics Data System (ADS)

Kumar, David D.; Morris, John D.

2005-12-01

A multiple regression analysis of the relationship between prospective teachers' scientific understanding and Gender, Education Level (High School, College), Courses in Science (Biology, Chemistry, Physics, Earth Science, Astronomy, and Agriculture), Attitude Towards Science, and Attitude Towards Mathematics is reported. Undergraduate elementary science students ( N = 176) in an urban doctoral-level university in the United States participated in this study. The results of this study showed Gender, completion of courses in High School Chemistry and Physics, College Chemistry and Physics, and Attitudes Toward Mathematics and Science significantly correlated with scientific understanding. Based on a regression model, Gender, and College Chemistry and Physics experiences added significant predictive accuracy to scientific understanding among prospective elementary teachers compared to the other variables.

The efficacy of World Wide Web-mediated microcomputer-based laboratory activities in the high school physics classroom

NASA Astrophysics Data System (ADS)

Slykhuis, David A.

This research project examined the efficacy of an online microcomputer-based laboratory based (MBL) physics unit. One hundred and fifty physics students from five high schools in North Carolina were divided into online and classroom groups. The classroom group completed the MBL unit in small groups with assistance from their teachers. The online groups completed the MBL unit in small groups using a website designed for this project for guidance. Pre- and post-unit content specific tests and surveys were given. Statistical analysis of the content tests showed significant development of conceptual understanding by the online group over the course of the unit. There was not a significant difference between the classroom and online group with relation to the amount of conceptual understanding developed. Correlations with post-test achievement showed that pre-test scores and math background were the most significant correlates with success. Computer related variables, such as computer comfort and online access, were only mildly correlated with the online group. Students' views about the nature of physics were not well developed prior to the unit and did not significantly change over the course of the unit. Examination of the students' physics conceptions after instruction revealed common alternative conceptions such as confusing position and velocity variables and incorrect interpretations of graphical features such as slope.

High-speed limnology: using advanced sensors to investigate spatial variability in biogeochemistry and hydrology.

PubMed

Crawford, John T; Loken, Luke C; Casson, Nora J; Smith, Colin; Stone, Amanda G; Winslow, Luke A

2015-01-06

Advanced sensor technology is widely used in aquatic monitoring and research. Most applications focus on temporal variability, whereas spatial variability has been challenging to document. We assess the capability of water chemistry sensors embedded in a high-speed water intake system to document spatial variability. This new sensor platform continuously samples surface water at a range of speeds (0 to >45 km h(-1)) resulting in high-density, mesoscale spatial data. These novel observations reveal previously unknown variability in physical, chemical, and biological factors in streams, rivers, and lakes. By combining multiple sensors into one platform, we were able to detect terrestrial-aquatic hydrologic connections in a small dystrophic lake, to infer the role of main-channel vs backwater nutrient processing in a large river and to detect sharp chemical changes across aquatic ecosystem boundaries in a stream/lake complex. Spatial sensor data were verified in our examples by comparing with standard lab-based measurements of selected variables. Spatial fDOM data showed strong correlation with wet chemistry measurements of DOC, and optical NO3 concentrations were highly correlated with lab-based measurements. High-frequency spatial data similar to our examples could be used to further understand aquatic biogeochemical fluxes, ecological patterns, and ecosystem processes, and will both inform and benefit from fixed-site data.

High-speed limnology: Using advanced sensors to investigate spatial variability in biogeochemistry and hydrology

USGS Publications Warehouse

Crawford, John T.; Loken, Luke C.; Casson, Nora J.; Smith, Collin; Stone, Amanda G.; Winslow, Luke A.

2015-01-01

Advanced sensor technology is widely used in aquatic monitoring and research. Most applications focus on temporal variability, whereas spatial variability has been challenging to document. We assess the capability of water chemistry sensors embedded in a high-speed water intake system to document spatial variability. This new sensor platform continuously samples surface water at a range of speeds (0 to >45 km h–1) resulting in high-density, mesoscale spatial data. These novel observations reveal previously unknown variability in physical, chemical, and biological factors in streams, rivers, and lakes. By combining multiple sensors into one platform, we were able to detect terrestrial–aquatic hydrologic connections in a small dystrophic lake, to infer the role of main-channel vs backwater nutrient processing in a large river and to detect sharp chemical changes across aquatic ecosystem boundaries in a stream/lake complex. Spatial sensor data were verified in our examples by comparing with standard lab-based measurements of selected variables. Spatial fDOM data showed strong correlation with wet chemistry measurements of DOC, and optical NO3 concentrations were highly correlated with lab-based measurements. High-frequency spatial data similar to our examples could be used to further understand aquatic biogeochemical fluxes, ecological patterns, and ecosystem processes, and will both inform and benefit from fixed-site data.

Quality assessment of osteoporosis clinical practice guidelines for physical activity and safe movement: an AGREE II appraisal.

PubMed

Armstrong, James Jacob; Rodrigues, Isabel Braganca; Wasiuta, Tom; MacDermid, Joy C

2016-01-01

Many osteoporosis clinical practice guidelines are published, and the extent to which physical activity and safe movement is addressed varies. To better inform clinical decision-making, a quality assessment and structured analysis of recommendations was undertaken. Guideline quality varied substantially, and improvement is necessary in physical activity and safe movement recommendations. The purpose of the present study is to survey available osteoporosis clinical practice guidelines (CPGs) containing physical activity and safe movement recommendations in order to assess the methodological quality with which they were developed. An analysis of the various physical activity and safe movement recommendations was conducted to determine variability between CPGs. An online literature search revealed 19 CPGs meeting our inclusion criteria. Three independent scorers evaluated CPG quality using the Appraisal of Guidelines for Research and Evaluation version II (AGREE II) instrument. Two separate individuals used a standard table to extract relevant recommendations. Intra-reviewer AGREE II score agreement ranged from fair to good (intra-class correlation coefficient (ICC) = 0.34 to 0.65). The quality of the 19 included CPGs was variable (AGREE sub-scores: 14 to 100%). CPGs scored higher in the "scope and purpose" and "clarity of presentation" domains. They scored the lowest in "applicability" and "editorial independence." Four CPGs were classified as high quality, ten average quality, and five low quality. Most CPGs recommended weight-bearing, muscle-strengthening, and resistance exercises. Information on exercise dosage, progression, and contraindications was often absent. Immobility and movements involving spinal flexion and/or torsion were discouraged. There were several high-quality CPGs; however, variability in quality and lack of specific parameters for implementation necessitates caution and critical examination by readers. CPG development groups should pay special attention to the clinical applicability of their CPGs as well as fully disclosing conflicts of interest. CPGs were in general an agreement regarding safe physical activity and safe movement recommendations. However, recommendations were often vague and the more specific recommendations were inconsistent between CPGs.

Shared decision making among parents of children with mental health conditions compared to children with chronic physical conditions.

PubMed

Butler, Ashley M; Elkins, Sara; Kowalkowski, Marc; Raphael, Jean L

2015-02-01

High quality care in pediatrics involves shared decision making (SDM) between families and providers. The extent to which children with common mental health disorders experience SDM is not well known. The objectives of this study were to examine how parent-reported SDM varies by child health (physical illness, mental health condition, and comorbid mental and physical conditions) and to examine whether medical home care attenuates any differences. We analyzed data on children (2-17 years) collected through the 2009/2010 National Survey of Children with Special Health Care Needs. The sample consisted of parents of children in one of three child health categories: (1) children with a chronic physical illness but no mental health condition; (2) children with a common mental health condition but no chronic physical condition; and (3) children with comorbid mental and chronic physical conditions. The primary dependent variable was parent-report of provider SDM. The primary independent variable was health condition category. Multivariate linear regression analyses were conducted. Multivariate analyses controlling for sociodemographic variables and parent-reported health condition impact indicated lower SDM among children with a common mental health condition-only (B = -0.40; p < 0.01) and children with comorbid conditions (B = -0.67; p < 0.01) compared to children with a physical condition-only. Differences in SDM for children with a common mental health condition-only were no longer significant in the model adjusting for medical home care. However, differences in SDM for children with comorbid conditions persisted after adjusting for medical home care. Increasing medical home care may help mitigate differences in SDM for children with mental health conditions-only. Other interventions may be needed to improve SDM among children with comorbid mental and physical conditions.

Can fitness and movement quality prevent back injury in elite task force police officers? A 5-year longitudinal study.

PubMed

McGill, Stuart; Frost, David; Lam, Thomas; Finlay, Tim; Darby, Kevin; Cannon, Jordan

2015-01-01

Elite police work has bursts of intense physically demanding work requiring high levels of fitness, or capacity, and movement competency; which are assumed to increase one's injury resilience. The purpose of this study was to follow members of an elite police force (N = 53) to test whether back injuries (N = 14) could be predicted from measures of fitness and movement quality. Measures of torso endurance, relative and absolute strength, hip ROM and movement quality using the Functional Movement Screen(TM) and other dynamic movement tests were obtained from every officer at baseline. When variables were grouped and considered holistically, rather than individually, back injury could be predicted. Seven variables best predicted those who would suffer a back injury (64% sensitivity and 95% specificity for an overall concordance of 87%). Overall, the ability to predict back injury was not high, suggesting that there is more complexity to this relationship than is explained with the variables tested here. Practitioner Summary: Members of elite police forces have exposure to intense physically demanding work. Increased levels of fitness and movement competency have been assumed to increase injury resilience. However, complexity in the interactions between exposure, movement competency, training, fitness and injury may occlude the true relationship between these variables.

Relationship between operational variables, fundamental physics and foamed cement properties in lab and field generated foamed cement slurries

DOE PAGES

Glosser, D.; Kutchko, B.; Benge, G.; ...

2016-03-21

Foamed cement is a critical component for wellbore stability. The mechanical performance of a foamed cement depends on its microstructure, which in turn depends on the preparation method and attendant operational variables. Determination of cement stability for field use is based on laboratory testing protocols governed by API Recommended Practice 10B-4 (API RP 10B-4, 2015). However, laboratory and field operational variables contrast considerably in terms of scale, as well as slurry mixing and foaming processes. Here in this paper, laboratory and field operational processes are characterized within a physics-based framework. It is shown that the “atomization energy” imparted by themore » high pressure injection of nitrogen gas into the field mixed foamed cement slurry is – by a significant margin – the highest energy process, and has a major impact on the void system in the cement slurry. There is no analog for this high energy exchange in current laboratory cement preparation and testing protocols. Quantifying the energy exchanges across the laboratory and field processes provides a basis for understanding relative impacts of these variables on cement structure, and can ultimately lead to the development of practices to improve cement testing and performance.« less

Physical Demand but Not Dexterity Is Associated with Motor Flexibility during Rapid Reaching in Healthy Young Adults

PubMed Central

Greve, Christian; Hortobàgyi, Tibor; Bongers, Raoul M.

2015-01-01

Healthy humans are able to place light and heavy objects in small and large target locations with remarkable accuracy. Here we examine how dexterity demand and physical demand affect flexibility in joint coordination and end-effector kinematics when healthy young adults perform an upper extremity reaching task. We manipulated dexterity demand by changing target size and physical demand by increasing external resistance to reaching. Uncontrolled manifold analysis was used to decompose variability in joint coordination patterns into variability stabilizing the end-effector and variability de-stabilizing the end-effector during reaching. Our results demonstrate a proportional increase in stabilizing and de-stabilizing variability without a change in the ratio of the two variability components as physical demands increase. We interpret this finding in the context of previous studies showing that sensorimotor noise increases with increasing physical demands. We propose that the larger de-stabilizing variability as a function of physical demand originated from larger sensorimotor noise in the neuromuscular system. The larger stabilizing variability with larger physical demands is a strategy employed by the neuromuscular system to counter the de-stabilizing variability so that performance stability is maintained. Our findings have practical implications for improving the effectiveness of movement therapy in a wide range of patient groups, maintaining upper extremity function in old adults, and for maximizing athletic performance. PMID:25970465

Comparing high and low acculturated mothers and physical activity in Hispanic children.

PubMed

Olvera, Norma; Smith, Dennis W; Lee, Chanam; Liu, Jian; Lee, Jay; Kim, Jun-Hyun; Kellam, Stephanie F

2011-09-01

Parents represent a key ecological component in influencing their child's physical activity. The aim of this exploratory study was to assess the relationship between maternal acculturation and physical activity in Hispanic children. 102 Hispanic mothers (mean age 36.2 yrs; +SD 7.3 yrs) and their children (mean age 10.0 yrs, +SD 0.8 yrs) participated. Most of the mothers (74%) were foreign-born, with 62% classified as low acculturated and 38% high acculturated. Demographic, acculturation, and anthropometric measures were completed by mothers and children. Physical activity was measured using accelerometers. Relationships between maternal acculturation and demographic variables and children's physical activity were examined using chi-square, Analysis of Variance, and simple regression. Children had higher physical activity levels than their mothers (t(49) = -7.87, P < .0001). Significant correlations between maternal and child's physical activity levels were observed in moderate (r2 = 0.13, P = .001), vigorous (r2 = 0.08, P = .05), and moderate-to-vigorous physical activity (r2 = 0.17, P = .002). Low acculturated mothers were more likely to have active children compared with high acculturated mothers. Maternal BMI and other demographic characteristics were not significantly associated with child's physical activity. Findings from this study revealed an association among maternal acculturation, role modeling, and child's physical activity.

Rural–Urban Differences in Objective and Subjective Measures of Physical Activity: Findings From the National Health and Nutrition Examination Survey (NHANES) 2003–2006

PubMed Central

Wen, Ming; Kowaleski-Jones, Lori

2014-01-01

Introduction Lower levels of physical activity among rural relative to urban residents have been suggested as an important contributor to rural–urban health disparity; however, empirical evidence is sparse. Methods We examined rural–urban differences in 4 objective physical activity measures (2 intensity thresholds by 2 bout lengths) and 4 subjective measures (total, leisure, household, and transportation) in a nationally representative sample of participants in the National Health and Nutrition Examination Survey (NHANES) 2003–2006. The sample comprised 5,056 adults aged 20 to 75 years. Rural-Urban Commuting Area (RUCA) codes were matched with NHANES subjects to identify urban status and 2 types of rural status. Rural–urban and within–rural differences in physical activity were estimated without and with controls for demographic and socioeconomic variables. Results Rural residents were less active than urban residents in high-intensity long bout (2,020 counts per minute threshold and 10 miniutes or longer bout length) accelerometer-measured physical activity (42.5 ± 6.2 min/wk vs 55.9 ± 2.8 min/wk) but the difference disappeared with a lower-intensity threshold (760 counts per minute). Rural residents reported more total physical activity than urban residents (438.3 ± 35.3min/wk vs 371.2 ± 12.5 min/wk), with differences primarily attributable to household physical activity. Within rural areas, micropolitan residents were less active than residents in smaller rural areas. Controlling for other variables reduced the size of the differences. Conclusion The direction and significance of rural–urban difference in physical activity varied by the method of physical activity measurement, likely related to rural residents spending more time in low-intensity household physical activity but less time in high-intensity physical activity. Micropolitan residents were substantially less active than residents in smaller rural areas, indicating that physical activity did not vary unidirectionally with degree of urbanization. PMID:25144676

Rural-urban differences in objective and subjective measures of physical activity: findings from the National Health and Nutrition Examination Survey (NHANES) 2003-2006.

PubMed

Fan, Jessie X; Wen, Ming; Kowaleski-Jones, Lori

2014-08-21

Lower levels of physical activity among rural relative to urban residents have been suggested as an important contributor to rural-urban health disparity; however, empirical evidence is sparse. We examined rural-urban differences in 4 objective physical activity measures (2 intensity thresholds by 2 bout lengths) and 4 subjective measures (total, leisure, household, and transportation) in a nationally representative sample of participants in the National Health and Nutrition Examination Survey (NHANES) 2003-2006. The sample comprised 5,056 adults aged 20 to 75 years. Rural-Urban Commuting Area (RUCA) codes were matched with NHANES subjects to identify urban status and 2 types of rural status. Rural-urban and within-rural differences in physical activity were estimated without and with controls for demographic and socioeconomic variables. Rural residents were less active than urban residents in high-intensity long bout (2,020 counts per minute threshold and 10 miniutes or longer bout length) accelerometer-measured physical activity (42.5 ± 6.2 min/wk vs 55.9 ± 2.8 min/wk) but the difference disappeared with a lower-intensity threshold (760 counts per minute). Rural residents reported more total physical activity than urban residents (438.3 ± 35.3min/wk vs 371.2 ± 12.5 min/wk), with differences primarily attributable to household physical activity. Within rural areas, micropolitan residents were less active than residents in smaller rural areas. Controlling for other variables reduced the size of the differences. The direction and significance of rural-urban difference in physical activity varied by the method of physical activity measurement, likely related to rural residents spending more time in low-intensity household physical activity but less time in high-intensity physical activity. Micropolitan residents were substantially less active than residents in smaller rural areas, indicating that physical activity did not vary unidirectionally with degree of urbanization.

Examination of Science and Math Course Achievements of Vocational High School Students in the Scope of Self-Efficacy and Anxiety

ERIC Educational Resources Information Center

Yüksel, Mehmet; Geban, Ömer

2016-01-01

This study attempted to predict physics, chemistry, and biology and math course achievements of vocational high school students according to the variables of student self-efficacy, academic self-efficacy, state anxiety and trait anxiety. Study data were collected using a questionnaire administered to the students of a vocational high school…

Mechanisms of the 40-70 Day Variability in the Yucatan Channel Volume Transport

NASA Astrophysics Data System (ADS)

van Westen, René M.; Dijkstra, Henk A.; Klees, Roland; Riva, Riccardo E. M.; Slobbe, D. Cornelis; van der Boog, Carine G.; Katsman, Caroline A.; Candy, Adam S.; Pietrzak, Julie D.; Zijlema, Marcel; James, Rebecca K.; Bouma, Tjeerd J.

2018-02-01

The Yucatan Channel connects the Caribbean Sea with the Gulf of Mexico and is the main outflow region of the Caribbean Sea. Moorings in the Yucatan Channel show high-frequent variability in kinetic energy (50-100 days) and transport (20-40 days), but the physical mechanisms controlling this variability are poorly understood. In this study, we show that the short-term variability in the Yucatan Channel transport has an upstream origin and arises from processes in the North Brazil Current. To establish this connection, we use data from altimetry and model output from several high resolution global models. A significant 40-70 day variability is found in the sea surface height in the North Brazil Current retroflection region with a propagation toward the Lesser Antilles. The frequency of variability is generated by intrinsic processes associated with the shedding of eddies, rather than by atmospheric forcing. This sea surface height variability is able to pass the Lesser Antilles, it propagates westward with the background ocean flow in the Caribbean Sea and finally affects the variability in the Yucatan Channel volume transport.

Wind, Circulation, and Topographic Effects on Alongshore Phytoplankton Variability in the California Current

NASA Astrophysics Data System (ADS)

Fiechter, Jerome; Edwards, Christopher A.; Moore, Andrew M.

2018-04-01

A physical-biogeochemical model is used to produce a retrospective analysis at 3-km resolution of alongshore phytoplankton variability in the California Current during 1988-2010. The simulation benefits from downscaling a regional circulation reanalysis, which provides improved physical ocean state estimates in the high-resolution domain. The emerging pattern is one of local upwelling intensification in response to increased alongshore wind stress in the lee of capes, modulated by alongshore meanders in the geostrophic circulation. While stronger upwelling occurs near most major topographic features, substantial increases in phytoplankton biomass only ensue where local circulation patterns are conducive to on-shelf retention of upwelled nutrients. Locations of peak nutrient delivery and chlorophyll accumulation also exhibit interannual variability and trends noticeably larger than the surrounding shelf regions, thereby suggesting that long-term planktonic ecosystem response in the California Current exhibits a significant local scale (O(100 km)) alongshore component.

Simulations of the Boreal Winter Upper Mesosphere and Lower Thermosphere With Meteorological Specifications in SD-WACCM-X

NASA Astrophysics Data System (ADS)

Sassi, Fabrizio; Siskind, David E.; Tate, Jennifer L.; Liu, Han-Li; Randall, Cora E.

2018-04-01

We investigate the benefit of high-altitude nudging in simulations of the structure and short-term variability of the upper mesosphere and lower thermosphere (UMLT) dynamical meteorology during boreal winter, specifically around the time of the January 2009 sudden stratospheric warming. We compare simulations using the Specified Dynamics, Whole Atmosphere Community Climate Model, extended version, nudged using atmospheric specifications generated by the Navy Operational Global Atmospheric Prediction System, Advanced Level Physics High Altitude. Two sets of simulations are carried out: one uses nudging over a vertical domain from 0 to 90 km; the other uses nudging over a vertical domain from 0 to 50 km. The dynamical behavior is diagnosed from ensemble mean and standard deviation of winds, temperature, and zonal accelerations due to resolved and parameterized waves. We show that the dynamical behavior of the UMLT is quite different in the two experiments, with prominent differences in the structure and variability of constituent transport. We compare the results of our numerical experiments to observations of carbon monoxide by the Atmospheric Chemistry Experiment-Fourier Transform Spectrometer to show that the high-altitude nudging is capable of reproducing with high fidelity the observed variability, and traveling planetary waves are a crucial component of the dynamics. The results of this study indicate that to capture the key physical processes that affect short-term variability (defined as the atmospheric behavior within about 10 days of a stratospheric warming) in the UMLT, specification of the atmospheric state in the stratosphere alone is not sufficient, and upper atmospheric specifications are needed.

Endogenous risk-taking and physical appearance of sex workers.

PubMed

Egger, Peter H; Lindenblatt, Andreas

2015-12-01

Previous research found that physical appearance affects the risk-taking of sex workers through offering unprotected services. This paper utilizes a large individual-level data set covering 16,583 pay-for-sex contracts in 2011 and 2012 by 2,517 female suppliers in Germany. Results based on instrumental variables suggest that the incentive for risk-taking is about twice as high than when assuming random assignment of risk-taking.

An Examination of Attitudes towards Cheating in Exams by Physical Education and Sports High School Students

ERIC Educational Resources Information Center

Kayisoglu, Numan Bahadir; Temel, Cenk

2017-01-01

The purpose of this study is to determine the attitudes of students from the Hasan Dogan School of Physical Education and Sports towards cheating in exams and to investigate changes in these attitudes in terms of several variables. The survey method was used in the study. The study was conducted during the 2014-2015 Academic year at the Karabük…

Outside-school physical activity participation and motivation in physical education.

PubMed

Shen, Bo

2014-03-01

Experience in non-school contexts can shape and reshape students' motivation and mediate their learning in school. Outside-school physical activity may provide students with an extensive cognitive and affective foundation and influence their motivation in physical education. Although a trans-contextual effect of physical education has been explored, very little empirical research has examined the impact from outside-school context to physical education. Using self-determination theory and a hierarchical model of motivation, this study was designed to examine the association between participation in organized outside-school physical activity programmes and self-determination process in physical education. Participants included 545 9th graders (305 males and 240 females, age range = 14-16 years, mean age = 14.66 years) enrolled in required physical education classes in three suburban high schools in a large Midwest metropolitan area in the United States. Self-determination variables were measured using relevant instruments, and information on organized outside-school physical activity experiences was gathered in a survey. Structural equation modelling analyses were conducted. Students who participated in organized outside-school physical activity programmes displayed overall higher motivation; however, the strength of associations among the self-determination variables (i.e., pathways from perceived autonomy support to relatedness, from autonomy to competence, and from self-determined motivation to in-class physical activity engagement) was stronger for their non-participant counterparts. There are dynamic relationships between participation in organized outside-school physical activity programmes and self-determination process in physical education. Physical educators need to identify, appreciate, and instructionally address individual students' differences during teaching and learning. © 2012 The British Psychological Society.

Association of physical capacity with heart rate variability based on a short-duration measurement of resting pulse rate in older adults with obesity

PubMed Central

Liao, Chun-De; Tsauo, Jau-Yih; Hsiao, Dun-Jen; Liou, Tsan-Hon

2017-01-01

Background Obesity can limit physical capacity and lower physical activity levels in elderly people. Low physical activity levels may be mediated by autonomic dysfunction with decreased heart rate variability (HRV). However, the relationship between autonomic dysfunction and low physical capability remains unclear. This cross-sectional study investigated the association of low physical capability with HRV in older adults with obesity. Materials and methods We recruited 231 old man and 210 old women with a mean (range) age of 65.5 (51−78) and 62.9 (52−76) years, respectively. Physical capability was measured using mobility tasks, including functional reach, single-leg stance (SLS), gait speed (GS), timed up and go, and timed chair rise (TCR), and the scores on these tasks were merged and transformed into a global physical capability score (GPCS). HRV was measured using a 7-min resting pulse-based technique, and the time- and frequency-domain indices of HRV were obtained including standard deviation of normal-to-normal intervals (SDNN), root mean square of successive differences at rest (rMSSD), and high-frequency (HF) power. All HRV indices were natural log (ln) transformed for analysis. Participants were divided into high, moderate, and low physical-capability groups according to their physical performance. Multivariate analysis of covariance was performed to test differences in HRV indices among physical-capability groups with participants’ characteristics serving as covariates. A stepwise regression model was established to identify the determinants of HRV indices. We used hierarchical regression analysis to identify the association of the GPCS with HRV indices. Results In both men and women, the low physical-capability group exhibited significantly increased heart rate (P <0.05) and decreased HRV in terms of a decreased ln[SDNN] (P <0.001), ln[rMSSD] (P <0.05) and ln[HF] (P <0.05), compared with the high physical-capability group. GS positively predicted ln[SDNN], whereas SLS, GS, and TCR were determinants of ln[HF], regardless of gender. The GPCS in older men and women independently accounted for 29.9% (P <0.001) and 23.7% (P <0.001), respectively, in variance in ln[SDNN]. Conclusions A low physical-capability level is an independent determinant of decreased HRV in older adults with obesity. PMID:29267296

Mineral Losses During Extreme Environmental Conditions

USDA-ARS?s Scientific Manuscript database

Advisory groups that make recommendations for mineral intakes continue to identify accurate determinations of sweat mineral losses during physical activity as a critical void in their deliberations. Although estimates of sweat mineral concentrations are available, they are highly variable. Practica...

Attitude Towards Physics and Additional Mathematics Achievement Towards Physics Achievement

ERIC Educational Resources Information Center

Veloo, Arsaythamby; Nor, Rahimah; Khalid, Rozalina

2015-01-01

The purpose of this research is to identify the difference in students' attitude towards Physics and Additional Mathematics achievement based on gender and relationship between attitudinal variables towards Physics and Additional Mathematics achievement with achievement in Physics. This research focused on six variables, which is attitude towards…

Ability to perform daily physical activities in individuals with type 2 diabetes and moderate obesity: a preliminary validation of the Impact of Weight on Activities of Daily Living Questionnaire.

PubMed

Hayes, Risa P; Nelson, David R; Meldahl, Michael L; Curtis, Bradley H

2011-07-01

The aims of this study were (1) to demonstrate the reliability and validity of the Impact of Weight on Activities of Daily Living Questionnaire (IWADL), a measure of ability to perform daily physical activities, in individuals with type 2 diabetes who are moderately obese and (2) to characterize those individuals with low self-reported ability. Data from a web-based survey of individuals with type 2 diabetes and body mass index (BMI) of 30-40 k/mg(2) were used to calculate Cronbach's α and demonstrate both IWADL factorial and construct validity. These data were entered into a multivariable multinomial logistic regression model with survey variables (demographics, health status, weight- and diabetes-related) as the independent variables and three IWADL scoring groups (Low, Medium, and High) as the dependent variables. Study participants were 349 individuals with type 2 diabetes (mean age = 59 years, 44% male, 91% white, mean BMI = 35 k/mg(2)). Factor analysis indicated a one-factor solution for a seven-item IWADL with Cronbach's α = 0.94. Significant (P < 0.05) relationships were identified between IWADL and variables previously shown to be related to level of physical activity. Ten variables remained independently (P < 0.05) related to IWADL scores, including age, gender, health status, current exercise, using exercise programs or hypnosis as a step to lose weight, and self-reported weight history. The IWADL is a reliable and valid measure of the ability of individuals with type 2 diabetes and moderate obesity to perform daily physical activities. This ability may be an important patient-reported end point to include in clinical trials of antihyperglycemic medications that produce weight loss.

Spatial Variability of Benthic-Pelagic Coupling in an Estuary Ecosystem: Consequences for Microphytobenthos Resuspension Phenomenon

PubMed Central

Ubertini, Martin; Lefebvre, Sébastien; Gangnery, Aline; Grangeré, Karine; Le Gendre, Romain; Orvain, Francis

2012-01-01

The high degree of physical factors in intertidal estuarine ecosystem increases material processing between benthic and pelagic compartments. In these ecosystems, microphytobenthos resuspension is a major phenomenon since its contribution to higher trophic levels can be highly significant. Understanding the sediment and associated microphytobenthos resuspension and its fate in the water column is indispensable for measuring the food available to benthic and pelagic food webs. To identify and hierarchize the physical/biological factors potentially involved in MPB resuspension, the entire intertidal area and surrounding water column of an estuarine ecosystem, the Bay des Veys, was sampled during ebb tide. A wide range of physical parameters (hydrodynamic regime, grain size of the sediment, and suspended matter) and biological parameters (flora and fauna assemblages, chlorophyll) were analyzed to characterize benthic-pelagic coupling at the bay scale. Samples were collected in two contrasted periods, spring and late summer, to assess the impact of forcing variables on benthic-pelagic coupling. A mapping approach using kriging interpolation enabled us to overlay benthic and pelagic maps of physical and biological variables, for both hydrological conditions and trophic indicators. Pelagic Chl a concentration was the best predictor explaining the suspension-feeders spatial distribution. Our results also suggest a perennial spatio-temporal structure of both benthic and pelagic compartments in the ecosystem, at least when the system is not imposed to intense wind, with MPB distribution controlled by both grain size and bathymetry. The benthic component appeared to control the pelagic one via resuspension phenomena at the scale of the bay. Co-inertia analysis showed closer benthic-pelagic coupling between the variables in spring. The higher MPB biomass observed in summer suggests a higher contribution to filter-feeders diets, indicating a higher resuspension effect in summer than in spring, in turn suggesting an important role of macrofauna bioturbation and filter feeding (Cerastoderma edule). PMID:22952910

Coupled effects of vertical mixing and benthic grazing on phytoplankton populations in shallow, turbid estuaries

USGS Publications Warehouse

Koseff, Jeffrey R.; Holen, Jacqueline K.; Monismith, Stephen G.; Cloern, James E.

1993-01-01

Coastal ocean waters tend to have very different patterns of phytoplankton biomass variability from the open ocean, and the connections between physical variability and phytoplankton bloom dynamics are less well established for these shallow systems. Predictions of biological responses to physical variability in these environments is inherently difficult because the recurrent seasonal patterns of mixing are complicated by aperiodic fluctuations in river discharge and the high-frequency components of tidal variability. We might expect, then, less predictable and more complex bloom dynamics in these shallow coastal systems compared with the open ocean. Given this complex and dynamic physical environment, can we develop a quantitative framework to define the physical regimes necessary for bloom inception, and can we identify the important mechanisms of physical-biological coupling that lead to the initiation and termination of blooms in estuaries and shallow coastal waters? Numerical modeling provides one approach to address these questions. Here we present results of simulation experiments with a refined version of Cloern's (1991) model in which mixing processes are treated more realistically to reflect the dynamic nature of turbulence generation in estuaries. We investigated several simple models for the turbulent mixing coefficient. We found that the addition of diurnal tidal variation to Cloern's model greatly reduces biomass growth indicating that variations of mixing on the time scale of hours are crucial. Furthermore, we found that for conditions representative of South San Francisco Bay, numerical simulations only allowed for bloom development when the water column was stratified and when minimal mixing was prescribed in the upper layer. Stratification, however, itself is not sufficient to ensure that a bloom will develop: minimal wind stirring is a further prerequisite to bloom development in shallow turbid estuaries with abundant populations of benthic suspension feeders.

Body composition and physical fitness in women with bulimia nervosa or binge‐eating disorder

PubMed Central

Rosenvinge, Jan H.; Friborg, Oddgeir; Pettersen, Gunn; Stensrud, Trine; Hansen, Bjørge Herman; Underhaug, Karoline E.; Teinung, Elisabeth; Vrabel, KariAnne; Svendsen, Mette; Bratland‐Sanda, Solfrid; Sundgot‐Borgen, Jorunn

2018-01-01

Abstract Objective Knowledge about physical fitness in women with bulimia nervosa (BN) or binge‐eating disorder (BED) is sparse. Previous studies have measured physical activity largely through self‐report, and physical fitness variables are mainly restricted to body mass index (BMI) and bone mineral density. We expanded the current knowledge in these groups by including a wider range of physical fitness indicators and objective measures of physical activity, assessed the influence of a history of anorexia nervosa (AN), and evaluated predictive variables for physical fitness. Method Physical activity, blood pressure, cardiorespiratory fitness (CRF), muscle strength, body composition, and bone mineral density were measured in 156 women with BN or BED, with mean (SD) age 28.4 years (5.7) and BMI 25.3 (4.8) kg m−2. Results Level of physical activity was higher than normative levels, still <50% met the official physical activity recommendation. Fitness in women with BN were on an average comparable with recommendations or normative levels, while women with BED had lower CRF and higher BMI, VAT, and body fat percentage. We found 10–12% with masked obesity. A history of AN did not predict current physical fitness, still values for current body composition were lower when comparing those with history of AN to those with no such history. Discussion Overall, participants with BN or BED displayed adequate physical fitness; however, a high number had unfavorable CRF and body composition. This finding calls for inclusion of physical fitness in routine clinical examinations and guided physical activity and dietary recommendations in the treatment of BN and BED. PMID:29473191

Relationships between Physical Activity Levels, Self-Identity, Body Dissatisfaction and Motivation among Spanish High School Students

PubMed Central

Sánchez-Miguel, Pedro Antonio; Leo, Francisco Miguel; Amado, Diana; Pulido, Juan José; Sánchez-Oliva, David

2017-01-01

Abstract The aim of this study was to examine the relationships between gender and the educational grade on the one hand, and physical activity levels, motivation, self-identity, body dissatisfaction, the intention to be physically active and daily sitting time on the other, in a sample of Spanish high school adolescents. The sample consisted of 2087 Spanish students from the 3rd (n = 1141) and 4th grade (n = 946), both male (n = 1046) and female (n = 1041), ranging in age from 15 to 17 years old (M = 15.42; SD = .86). Students completed questionnaires to assess their levels of physical activity, self-identity, motivation, intention to be physically active and daily sitting time. The students’ perceptions of their body height and mass were also tested. With the exception of walking MET values, the results showed gender differences in the variables tested. Male participants showed higher intrinsic motivation and lower amotivation than female participants. Furthermore, male students revealed higher levels of physical activity than female students. Finally, the research concluded with the importance of promoting intrinsic reasons for physical activity in order to encourage positive consequences in high school students. PMID:29134046

Relationships between Physical Activity Levels, Self-Identity, Body Dissatisfaction and Motivation among Spanish High School Students.

PubMed

Sánchez-Miguel, Pedro Antonio; Leo, Francisco Miguel; Amado, Diana; Pulido, Juan José; Sánchez-Oliva, David

2017-10-01

The aim of this study was to examine the relationships between gender and the educational grade on the one hand, and physical activity levels, motivation, self-identity, body dissatisfaction, the intention to be physically active and daily sitting time on the other, in a sample of Spanish high school adolescents. The sample consisted of 2087 Spanish students from the 3rd (n = 1141) and 4th grade (n = 946), both male (n = 1046) and female (n = 1041), ranging in age from 15 to 17 years old (M = 15.42; SD = .86). Students completed questionnaires to assess their levels of physical activity, self-identity, motivation, intention to be physically active and daily sitting time. The students' perceptions of their body height and mass were also tested. With the exception of walking MET values, the results showed gender differences in the variables tested. Male participants showed higher intrinsic motivation and lower amotivation than female participants. Furthermore, male students revealed higher levels of physical activity than female students. Finally, the research concluded with the importance of promoting intrinsic reasons for physical activity in order to encourage positive consequences in high school students.

Associations of out of school physical activity, sedentary lifestyle and socioeconomic status with weight status and adiposity of Cameroon children.

PubMed

Navti, Lifoter K; Atanga, Mary B; Niba, Loveline L

2017-01-01

Low physical activity and a sedentary lifestyle are contributing to overweight/obesity in children. This study aims to explore relationships between out of school physical activity, sedentary lifestyle and socioeconomic status indicators with children's weight status and adiposity. Five hundred twenty-two children of ages 5 to 12 years were randomly selected in a school-based cross sectional study in Bamenda, Cameroon. Weight and height were measured and BMI calculated. These variables were standardized for age and gender. Socioeconomic variables and proxy measures of physical activity and sedentary lifestyle of children were reported by parents using a structured questionnaire. Bivariate and multivariable logistic regression was used to calculate odds ratios.Quantile regression was used to compare median values of triceps skinfold thickness across the different factors. In bivariate analysis, physical activity > 4 - 7 times/week was significantly ( p  = 0.010) associated with a lower prevalence (5.9%) of overweight/obesity. In multivariable analysis, physical activity > twice a week (OR 0.1, 95% CI 0.05 - 0.3), sedentary lifestyle > 3 h/day (OR 2.4, 95% CI 1.2 - 4.3) and being in the high occupation class (OR 4.3, 95% CI 2.2 - 8.1) independently predicted overweight/obesity. With quantile regression, physical activity > 4 - 7 times/week was significantly ( p  = 0.023) associated with a 1.36 mm decrease in median triceps skinfold thickness, while sedentary lifestyle (> 3 h/day) ( p  = 0.026) and being in the high occupation class ( p  = 0.007) were significantly associated with a 1.37 mm and 1.86 mm increase in median triceps skinfold thickness respectively. Physical activity is inversely related to BMI-defined overweight/obesity and triceps skinfold thickness. Also, a high sedentary lifestyle and a high occupation class were associated with overweight/obesity and had the largest significant relationship with triceps skinfold thickness. There is need to objectively assess physical activity and sedentary lifestyle in our setting, in and out of school. Also longitudinal studies are warranted to understand the influence of cultural and behavioral drivers of physical activity and sedentary lifestyle.

Biological community structure on patch reefs in Biscayne National Park, FL, USA

USGS Publications Warehouse

Kuffner, Ilsa B.; Grober-Dunsmore, Rikki; Brock, John C.; Hickey, T. Don

2010-01-01

Coral reef ecosystem management benefits from continual quantitative assessment of the resources being managed, plus assessment of factors that affect distribution patterns of organisms in the ecosystem. In this study, we investigate the relationships among physical, benthic, and fish variables in an effort to help explain the distribution patterns of organisms on patch reefs within Biscayne National Park, FL, USA. We visited a total of 196 randomly selected sampling stations on 12 shallow (<10 m) patch reefs and measured physical variables (e.g., substratum rugosity, substratum type) and benthic and fish community variables. We also incorporated data on substratum rugosity collected remotely via airborne laser surveying (Experimental Advanced Airborne Research Lidar—EAARL). Across all stations, only weak relationships were found between physical, benthic cover, and fish assemblage variables. Much of the variance was attributable to a “reef effect,” meaning that community structure and organism abundances were more variable at stations among reefs than within reefs. However, when the reef effect was accounted for and removed statistically, patterns were detected. Within reefs, juvenile scarids were most abundant at stations with high coverage of the fleshy macroalgae Dictyota spp., and the calcified alga Halimeda tuna was most abundant at stations with low EAARL rugosity. Explanations for the overwhelming importance of “reef” in explaining variance in our dataset could include the stochastic arrangement of organisms on patch reefs related to variable larval recruitment in space and time and/or strong historical effects due to patchy disturbances (e.g., hurricanes, fishing), as well as legacy effects of prior residents (“priority” effects).

Quantifying daily physical activity and determinants in sedentary patients with Parkinson's disease.

PubMed

Dontje, M L; de Greef, M H G; Speelman, A D; van Nimwegen, M; Krijnen, W P; Stolk, R P; Kamsma, Y P T; Bloem, B R; Munneke, M; van der Schans, C P

2013-10-01

Although physical activity is beneficial for Parkinson's disease (PD) patients, many do not meet the recommended levels. The range of physical activity among sedentary PD patients is unknown, as are factors that determine this variability. Hence, we aimed to (1) assess daily physical activity in self-identified sedentary PD patients; (2) compare this with criteria of a daily physical activity guideline; and (3) identify determinants of daily physical activity. Daily physical activity of 586 self-identified sedentary PD patients was measured with a tri-axial accelerometer for seven consecutive days. Physical fitness and demographic, disease-specific, and psychological characteristics were assessed. Daily physical activity was compared with the 30-min activity guideline. A linear mixed-effects model was estimated to identify determinants of daily physical activity. Accelerometer data of 467 patients who fulfilled all criteria revealed that >98% of their day was spent on sedentary to light-intensity activities. Eighty-two percent of the participants were 'physically inactive' (0 days/week of 30-min activity); 17% were 'semi-active' (1-4 days/week of 30-min activity). Age, gender, physical fitness, and scores on the Unified Parkinson's Disease Rating Scale explained 69% of the variability in daily physical activity. Performance-based measurements confirmed that most self-identified sedentary PD patients are 'physically inactive'. However, the variance in daily physical activity across subjects was considerable. Higher age, being female, and lower physical capacity were the most important determinants of reduced daily physical activity. Future therapeutic interventions should aim to improve daily physical activity in these high-risk patients, focusing specifically on modifiable risk factors. Copyright © 2013 Elsevier Ltd. All rights reserved.

The influence of spatially and temporally varying oceanographic conditions on meroplanktonic metapopulations

NASA Astrophysics Data System (ADS)

Botsford, L. W.; Moloney, C. L.; Hastings, A.; Largier, J. L.; Powell, T. M.; Higgins, K.; Quinn, J. F.

We synthesize the results of several modelling studies that address the influence of variability in larval transport and survival on the dynamics of marine metapopulations distributed along a coast. Two important benthic invertebrates in the California Current System (CCS), the Dungeness crab and the red sea urchin, are used as examples of the way in which physical oceanographic conditions can influence stability, synchrony and persistence of meroplanktonic metapopulations. We first explore population dynamics of subpopulations and metapopulations. Even without environmental forcing, isolated local subpopulations with density-dependence can vary on time scales roughly twice the generation time at high adult survival, shifting to annual time scales at low survivals. The high frequency behavior is not seen in models of the Dungeness crab, because of their high adult survival rates. Metapopulations with density-dependent recruitment and deterministic larval dispersal fluctuate in an asynchronous fashion. Along the coast, abundance varies on spatial scales which increase with dispersal distance. Coastwide, synchronous, random environmental variability tends to synchronize these metapopulations. Climate change could cause a long-term increase or decrease in mean larval survival, which in this model leads to greater synchrony or extinction respectively. Spatially managed metapopulations of red sea urchins go extinct when distances between harvest refugia become greater than the scale of larval dispersal. All assessments of population dynamics indicate that metapopulation behavior in general dependes critically on the temporal and spatial nature of larval dispersal, which is largely determined by physical oceanographic conditions. We therfore explore physical influences on larval dispersal patterns. Observed trends in temperature and salinity applied to laboratory-determined responses indicate that natural variability in temperature and salinity can lead to variability in larval development period on interannual (50%), intra-annual (20%) and latitudinal (200%) scales. Variability in development period significantly influences larval survival and, thus, net transport. Larval drifters that undertake diel vertical migration in a primitive equation model of coastal circulation (SPEM) demonstrate the importance of vertical migration in determining horizontal transport. Empirically derived estimates of the effects of wind forcing on larval transport of vertically migrating larvae (wind drift when near the surface and Ekman transport below the surface) match cross-shelf distributions in 4 years of existing larval data. We use a one-dimensional advection-diffusion model, which includes intra-annual timing of cross-shelf flows in the CCS, to explore the combined effects on settlement: (1) temperature- and salinity-dependent development and survival rates and (2) possible horizontal transport due to vertical migration of crab larvae. Natural variability in temperature, wind forcing, and the timing of the spring transition can cause the observed variability in recruitment. We conclude that understanding the dynamics of coastally distributed metapopulations in response to physically-induced variability in larval dispersal will be a critical step in assessing the effects of climate change on marine populations.

Work-life conflict and associations with work- and nonwork-related factors and with physical and mental health outcomes: a nationally representative cross-sectional study in Switzerland

PubMed Central

2009-01-01

Background The aim of the present cross-sectional study was to examine work- and nonwork- related factors and physical and mental health outcomes associated with combined time- and strain-based work-life conflict (WLC) among adult employees living and working in Switzerland as well as possible gender differences in this regard. Methods The data used for the study were taken from wave 6 of the nationally representative Swiss Household Panel (SHP) collected in 2004. The analysis was restricted to 4'371 employees aged 20 to 64 years. Trivariate crosstabulations and multivariate linear and logistic regression analyses stratified by gender were performed in order to calculate gender-specific prevalence rates (%), beta coefficients (β) and crude as well as multiple adjusted odds ratios (OR) as measures of association. Results Every eighth person (12.5%) within the study population has a high or very high WLC score. Prevalence rates are clearly above average in men and women with higher education, in executive positions or managerial functions, in full-time jobs, with variable work schedules, regular overtime, long commuting time to work and job insecurity. Working overtime regularly, having variable work schedules and being in a management position are most strongly associated with WLC in men, whereas in women the level of employment is the strongest explanatory variable by far, followed by variable work schedules and high job status (managerial position). In both men and women, WLC is associated with several physical and mental health problems. Employees with high or very high WLC show a comparatively high relative risk of self-reported poor health, anxiety and depression, lack of energy and optimism, serious backache, headaches, sleep disorders and fatigue. While overall prevalence rate of (very) high WLC is higher in men than in women, associations between degrees of WLC and most health outcomes are stronger in women than in men. Conclusion This important issue which up to now has been largely neglected in public health research needs to be addressed in future public health research and, if the findings are confirmed by subsequent (longitudinal) studies, to be considered in workplace health promotion and interventions in Switzerland as elsewhere. PMID:19943980

Work-life conflict and associations with work- and nonwork-related factors and with physical and mental health outcomes: a nationally representative cross-sectional study in Switzerland.

PubMed

Hämmig, Oliver; Gutzwiller, Felix; Bauer, Georg

2009-11-30

The aim of the present cross-sectional study was to examine work- and nonwork- related factors and physical and mental health outcomes associated with combined time- and strain-based work-life conflict (WLC) among adult employees living and working in Switzerland as well as possible gender differences in this regard. The data used for the study were taken from wave 6 of the nationally representative Swiss Household Panel (SHP) collected in 2004. The analysis was restricted to 4'371 employees aged 20 to 64 years. Trivariate crosstabulations and multivariate linear and logistic regression analyses stratified by gender were performed in order to calculate gender-specific prevalence rates (%), beta coefficients (beta) and crude as well as multiple adjusted odds ratios (OR) as measures of association. Every eighth person (12.5%) within the study population has a high or very high WLC score. Prevalence rates are clearly above average in men and women with higher education, in executive positions or managerial functions, in full-time jobs, with variable work schedules, regular overtime, long commuting time to work and job insecurity. Working overtime regularly, having variable work schedules and being in a management position are most strongly associated with WLC in men, whereas in women the level of employment is the strongest explanatory variable by far, followed by variable work schedules and high job status (managerial position). In both men and women, WLC is associated with several physical and mental health problems. Employees with high or very high WLC show a comparatively high relative risk of self-reported poor health, anxiety and depression, lack of energy and optimism, serious backache, headaches, sleep disorders and fatigue. While overall prevalence rate of (very) high WLC is higher in men than in women, associations between degrees of WLC and most health outcomes are stronger in women than in men. This important issue which up to now has been largely neglected in public health research needs to be addressed in future public health research and, if the findings are confirmed by subsequent (longitudinal) studies, to be considered in workplace health promotion and interventions in Switzerland as elsewhere.

Continuity and change in social and physical aggression from middle childhood through early adolescence.

PubMed

Underwood, Marion K; Beron, Kurt J; Rosen, Lisa H

2009-01-01

For a sample followed from age 9-13 (N=281), this investigation examined developmental trajectories for social and physical aggression as measured by teacher ratings. Trajectories for both forms of aggression were estimated first separately, then jointly. Mean levels of both social and physical aggression decreased over time for the overall sample, but with high variability of individual trajectories. Subgroups followed high trajectories for both social and physical aggression. Joint estimation yielded six trajectories: low stable, low increasers, medium increasers, medium desisters, high desisters, and high increasers. Membership in the high increaser group was predicted by male gender, unmarried parents, African American ethnicity, and maternal authoritarian and permissive parenting. Permissive parenting also predicted membership in the medium increaser group. This is one of the first studies to examine social aggression longitudinally across this developmental period. Though the results challenge the claim that social aggression is at its peak in early adolescence, the findings emphasize the importance of considering different developmental trajectories in trying to understand origins and outcomes of aggression.

Continuity and Change in Social and Physical Aggression from Middle Childhood through Early Adolescence

PubMed Central

Underwood, Marion K.; Beron, Kurt J.; Rosen, Lisa H.

2009-01-01

For a sample followed from age 9–13 (N=281), this investigation examined developmental trajectories for social and physical aggression as measured by teacher ratings. Trajectories for both forms of aggression were estimated first separately, then jointly. Mean levels of both social and physical aggression decreased over time for the overall sample, but with high variability of individual trajectories. Subgroups followed high trajectories for both social and physical aggression. Joint estimation yielded six trajectories: low stable, low increasers, medium increasers, medium desisters, high desisters, and high increasers. Membership in the high increaser group was predicted by male gender, unmarried parents, African American ethnicity, and maternal authoritarian and permissive parenting. Permissive parenting also predicted membership in the medium increaser group. This is one of the first studies to examine social aggression longitudinally across this developmental period. Though the results challenge the claim that social aggression is at its peak in early adolescence, the findings emphasize the importance of considering different developmental trajectories in trying to understand origins and outcomes of aggression. PMID:19685551

School physics teacher class management, laboratory practice, student engagement, critical thinking, cooperative learning and use of simulations effects on student performance

NASA Astrophysics Data System (ADS)

Riaz, Muhammad

The purpose of this study was to examine how simulations in physics class, class management, laboratory practice, student engagement, critical thinking, cooperative learning, and use of simulations predicted the percentage of students achieving a grade point average of B or higher and their academic performance as reported by teachers in secondary school physics classes. The target population consisted of secondary school physics teachers who were members of Science Technology, Engineeering and,Mathematics Teachers of New York City (STEMteachersNYC) and American Modeling Teachers Association (AMTA). They used simulations in their physics classes in the 2013 and 2014 school years. Subjects for this study were volunteers. A survey was constructed based on a literature review. Eighty-two physics teachers completed the survey about instructional practice in physics. All respondents were anonymous. Classroom management was the only predictor of the percent of students achieving a grade point average of B or higher in high school physics class. Cooperative learning, use of simulations, and student engagement were predictors of teacher's views of student academic performance in high school physics class. All other variables -- class management, laboratory practice, critical thinking, and teacher self-efficacy -- were not predictors of teacher's views of student academic performance in high school physics class. The implications of these findings were discussed and recommendations for physics teachers to improve student learning were presented.

An inexpensive, multipurpose physical pendulum

NASA Astrophysics Data System (ADS)

Schultz, David

2012-10-01

The pendulum is a highly versatile tool for teaching physics. Many special purpose pendula for student experiments have been described.1-4 In this paper, I describe an inexpensive, multipurpose physical pendulum that can function as both a variable gravity and ballistic pendulum. I designed the apparatus for use in a rotational dynamics unit of the AP Physics C mechanics course. The use of a bike wheel hub pivot allows for low-friction, rugged operation that yields results commensurate with those obtained with much more expensive pendula available on the market (typically 500 per unit5), placing these types of experiments within reach of the teacher on a restricted budget.

An analysis of predictors of enrollment and successful achievement for girls in high school Advanced Placement physics

NASA Astrophysics Data System (ADS)

Depalma, Darlene M.

A problem within science education in the United States persists. U.S students rank lower in science than most other students from participating countries on international tests of achievement (National Center for Education Statistics, 2003). In addition, U.S. students overall enrollment rate in high school Advanced Placement (AP) physics is still low compared to other academic domains, especially for females. This problem is the background for the purpose of this study. This investigation examined cognitive and motivational variables thought to play a part in the under-representation of females in AP physics. Cognitive variables consisted of mathematics, reading, and science knowledge, as measured by scores on the 10th and 11th grade Florida Comprehensive Assessment Tests (FCAT). The motivational factors of attitude, stereotypical views toward science, self-efficacy, and epistemological beliefs were measured by a questionnaire developed with questions taken from previously proven reliable and valid instruments. A general survey regarding participation in extracurricular activities was also included. The sample included 12th grade students from two high schools located in Seminole County, Florida. Of the 106 participants, 20 girls and 27 boys were enrolled in AP physics, and 39 girls and 20 boys were enrolled in other elective science courses. Differences between males and females enrolled in AP physics were examined, as well as differences between females enrolled in AP physics and females that chose not to participate in AP physics, in order to determine predictors that apply exclusively to female enrollment in high school AP physics and predictors of an anticipated science related college major. Data were first analyzed by Exploratory Factor Analysis, followed by Analysis of Variance (ANOVA), independent t-tests, univariate analysis, and logistic regression analysis. One overall theme that emerged from this research was findings that refute the ideas that females have lower achievement scores, lower attitude, lower self-efficacy, and more stereotypical views regarding science than males. Secondly, the only significant differences found between males and females enrolled in AP physics were for stereotypical views toward science and one factor from the epistemological views questions, both of which favored females. Although the non AP boys significantly outscored non AP girls on science FCAT scores, the only other significant differences found between these groups of students were related to attitude, with the girls scoring higher than the boys on both counts. There were significant differences found for numerous variables between AP and non AP females, however, most of the same differences were found between the two ability groups of male students as well. This leads to the conclusion that these factors certainly play an important role in AP physics enrollment for both genders. But the few significant differences found exclusively between the two female ability groups; reading ability, stereotypical views toward science, and the epistemological beliefs regarding branches of physics being related by common principles and aspects of physics need to be inferred instead of directly measured, may play a more important role in increasing enrollment numbers of females.

The impact of sociodemographic factors vs. gender roles on female hospital workers' health: do we need to shift emphasis?

PubMed

Musshauser, Doris; Bader, Angelika; Wildt, Beatrice; Hochleitner, Margarethe

2006-09-01

The aim of the present study was to evaluate the physical and mental health status of female workers from five different occupational groups and to identify possible sociodemographic and gender-coded family-related factors as well as work characteristics influencing women's health. The identified predictors of health status were subjected to a gender-sensitive analysis and their relations to one another are discussed. A total of 1083 female hospital workers including medical doctors, technical and administrative personnel, nurses and a group mainly consisting of scientific personnel and psychologists completed a questionnaire measuring work- and family-related variables, sociodemographic data and the Short-form 36 Health Questionnaire (SF-36). Data were analysed by multivariate regression analyses. Female medical doctors reported highest scores for all physical health dimensions except General Health. Our study population showed general low mental health status among administrative personnel and the heterogeneous group, others, scored highest on all mental health component scores. A series of eight regression analyses were performed. Three variables contributed highly significantly to all SF-36 subscale scores: age, satisfaction with work schedule, and the unpaid work variable. Age had the strongest influence on all physical dimensions except General Health (beta=-0.17) and had no detectable influence on mental health scores. The unpaid work variable (beta=-0.23; p<0.001) exerted a stronger influence on General Health than did age. Nevertheless, these variables were limited predictors of physical and mental health status. In all occupational groups the amount of time spent daily on child care and household tasks, as a traditional gender-coded factor, and satisfaction with work schedule were the only contributors to mental health among working women in this study. Traditional sociodemographic data had no effect on mental health status. In addition to age, these factors were shown to be the only predictors of physical health status of female workers. Gender coded-factors matter. These findings underline the importance of including gender-coded family- and work-related variables in medical research over and above basic sociodemographic data in order to describe study populations more clearly.

Supercritical Fuel Pyrolysis

DTIC Science & Technology

2007-05-28

be supercritical fluids . These temperatures and pressures will also cause the fuel to undergo pyrolytic reactions, which have the potential of forming...physical properties, supercritical fluids have highly variable densities, no surface tension, and transport properties (i.e., mass, energy, and momentum...are very dependent on pressure, chemical reaction rates in supercritical fluids can be highly pressure-dependent [6-9]. The kinetic reaction rate

A meteorological distribution system for high-resolution terrestrial modeling (MicroMet)

Treesearch

Glen E. Liston; Kelly Elder

2006-01-01

An intermediate-complexity, quasi-physically based, meteorological model (MicroMet) has been developed to produce high-resolution (e.g., 30-m to 1-km horizontal grid increment) atmospheric forcings required to run spatially distributed terrestrial models over a wide variety of landscapes. The following eight variables, required to run most terrestrial models, are...

Phenological Responses to ENSO in the Global Oceans

NASA Astrophysics Data System (ADS)

Racault, M.-F.; Sathyendranath, S.; Menon, N.; Platt, T.

2017-01-01

Phenology relates to the study of timing of periodic events in the life cycle of plants or animals as influenced by environmental conditions and climatic forcing. Phenological metrics provide information essential to quantify variations in the life cycle of these organisms. The metrics also allow us to estimate the speed at which living organisms respond to environmental changes. At the surface of the oceans, microscopic plant cells, so-called phytoplankton, grow and sometimes form blooms, with concentrations reaching up to 100 million cells per litre and extending over many square kilometres. These blooms can have a huge collective impact on ocean colour, because they contain chlorophyll and other auxiliary pigments, making them visible from space. Phytoplankton populations have a high turnover rate and can respond within hours to days to environmental perturbations. This makes them ideal indicators to study the first-level biological response to environmental changes. In the Earth's climate system, the El Niño-Southern Oscillation (ENSO) dominates large-scale inter-annual variations in environmental conditions. It serves as a natural experiment to study and understand how phytoplankton in the ocean (and hence the organisms at higher trophic levels) respond to climate variability. Here, the ENSO influence on phytoplankton is estimated through variations in chlorophyll concentration, primary production and timings of initiation, peak, termination and duration of the growing period. The phenological variabilities are used to characterise phytoplankton responses to changes in some physical variables: sea surface temperature, sea surface height and wind. It is reported that in oceanic regions experiencing high annual variations in the solar cycle, such as in high latitudes, the influence of ENSO may be readily measured using annual mean anomalies of physical variables. In contrast, in oceanic regions where ENSO modulates a climate system characterised by a seasonal reversal of the wind forcing, such as the monsoon system in the Indian Ocean, phenology-based mean anomalies of physical variables help refine evaluation of the mechanisms driving the biological responses and provide a more comprehensive understanding of the integrated processes.

CRPropa 3—a public astrophysical simulation framework for propagating extraterrestrial ultra-high energy particles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Batista, Rafael Alves; Dundovic, Andrej; Sigl, Guenter

2016-05-01

We present the simulation framework CRPropa version 3 designed for efficient development of astrophysical predictions for ultra-high energy particles. Users can assemble modules of the most relevant propagation effects in galactic and extragalactic space, include their own physics modules with new features, and receive on output primary and secondary cosmic messengers including nuclei, neutrinos and photons. In extension to the propagation physics contained in a previous CRPropa version, the new version facilitates high-performance computing and comprises new physical features such as an interface for galactic propagation using lensing techniques, an improved photonuclear interaction calculation, and propagation in time dependent environmentsmore » to take into account cosmic evolution effects in anisotropy studies and variable sources. First applications using highlighted features are presented as well.« less

Sociodemographic and socioeconomic variations in leisure time physical activity in a sample of Hungarian youth.

PubMed

Piko, Bettina F; Keresztes, Noémi

2008-01-01

The main goal of the present study is to detect the relationship between youth's leisure time physical activity and a set of sociodemographic (age, gender, family stucture) and socioeconomic variables (SES and parental schooling). Data were collected among Hungarian youth (middle and high school students, N = 1662) aged between 10-20 years using a self-administered questionnaire. Our findings did not indicate gender differences during the years of middle school, whereas gender differences became significant during the years of high school. In multivariate analyses, parental schooling played a decisive role in youth's physical activity, wheres SES self-assessment did not remain significant. These findings provide some useful information on characteristics of the target groups for health education programs.

Use of research-based instructional strategies in introductory physics: Where do faculty leave the innovation-decision process?

NASA Astrophysics Data System (ADS)

Henderson, Charles; Dancy, Melissa; Niewiadomska-Bugaj, Magdalena

2012-12-01

During the fall of 2008 a web survey, designed to collect information about pedagogical knowledge and practices, was completed by a representative sample of 722 physics faculty across the United States (50.3% response rate). This paper presents partial results to describe how 20 potential predictor variables correlate with faculty knowledge about and use of research-based instructional strategies (RBIS). The innovation-decision process was conceived of in terms of four stages: knowledge versus no knowledge, trial versus no trial, continuation versus discontinuation, and high versus low use. The largest losses occur at the continuation stage, with approximately 1/3 of faculty discontinuing use of all RBIS after trying one or more of these strategies. Nine of the predictor variables were statistically significant for at least one of these stages when controlling for other variables. Knowledge and/or use of RBIS are significantly correlated with reading teaching-related journals, attending talks and workshops related to teaching, attending the physics and astronomy new faculty workshop, having an interest in using more RBIS, being female, being satisfied with meeting instructional goals, and having a permanent, full-time position. The types of variables that are significant at each stage vary substantially. These results suggest that common dissemination strategies are good at creating knowledge about RBIS and motivation to try a RBIS, but more work is needed to support faculty during implementation and continued use of RBIS. Also, contrary to common assumptions, faculty age, institutional type, and percentage of job related to teaching were not found to be barriers to knowledge or use at any stage. High research productivity and large class sizes were not found to be barriers to use of at least some RBIS.

Detection and Attribution of Simulated Climatic Extreme Events and Impacts: High Sensitivity to Bias Correction

NASA Astrophysics Data System (ADS)

Sippel, S.; Otto, F. E. L.; Forkel, M.; Allen, M. R.; Guillod, B. P.; Heimann, M.; Reichstein, M.; Seneviratne, S. I.; Kirsten, T.; Mahecha, M. D.

2015-12-01

Understanding, quantifying and attributing the impacts of climatic extreme events and variability is crucial for societal adaptation in a changing climate. However, climate model simulations generated for this purpose typically exhibit pronounced biases in their output that hinders any straightforward assessment of impacts. To overcome this issue, various bias correction strategies are routinely used to alleviate climate model deficiencies most of which have been criticized for physical inconsistency and the non-preservation of the multivariate correlation structure. We assess how biases and their correction affect the quantification and attribution of simulated extremes and variability in i) climatological variables and ii) impacts on ecosystem functioning as simulated by a terrestrial biosphere model. Our study demonstrates that assessments of simulated climatic extreme events and impacts in the terrestrial biosphere are highly sensitive to bias correction schemes with major implications for the detection and attribution of these events. We introduce a novel ensemble-based resampling scheme based on a large regional climate model ensemble generated by the distributed weather@home setup[1], which fully preserves the physical consistency and multivariate correlation structure of the model output. We use extreme value statistics to show that this procedure considerably improves the representation of climatic extremes and variability. Subsequently, biosphere-atmosphere carbon fluxes are simulated using a terrestrial ecosystem model (LPJ-GSI) to further demonstrate the sensitivity of ecosystem impacts to the methodology of bias correcting climate model output. We find that uncertainties arising from bias correction schemes are comparable in magnitude to model structural and parameter uncertainties. The present study consists of a first attempt to alleviate climate model biases in a physically consistent way and demonstrates that this yields improved simulations of climate extremes and associated impacts. [1] http://www.climateprediction.net/weatherathome/

Determinants of child maltreatment in Nepal: Results from the 2014 Nepal multiple indicator cluster survey (the 2014 NMICS).

PubMed

Atteraya, Madhu Sudhan; Ebrahim, Nasser B; Gnawali, Shreejana

2018-02-01

We examined the prevalence of child maltreatment as measured by the level of physical (moderate to severe) and emotional abuse and child labor, and the associated household level determinants of child maltreatment in Nepal. We used a nationally representative data set from the fifth round of the Nepal Multiple Indicator Cluster Survey (the 2014 NMICS). The main independent variables were household level characteristics. Dependent variables included child experience of moderate to severe physical abuse, emotional abuse, and child labor (domestic work and economic activities). Bivariate analyses and logistic regressions were used to examine the associations between independent and dependent variables. The results showed that nearly half of the children (49.8%) had experienced moderate physical abuse, 21.5% experienced severe physical abuse, and 77.3% experienced emotional abuse. About 27% of the children had engaged in domestic work and 46.7% in various economic activities. At bivariate level, educational level of household's head and household wealth status had shown significant statistical association with child maltreatment (p<0.001). Results from multivariate logistic regressions showed that higher education levels and higher household wealth status protected children from moderate to severe physical abuse, emotional abuse and child labor. In general, child maltreatment is a neglected social issue in Nepal and the high rates of child maltreatment calls for mass awareness programs focusing on parents, and involving all stakeholders including governments, local, and international organizations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cross-sectional observation of the relationship of depressive symptoms with lifestyles and parents' status among Japanese junior high school students.

PubMed

Hyakutake, Aiko; Kamijo, Tomoko; Misawa, Yuka; Washizuka, Shinsuke; Inaba, Yuji; Tsukahara, Teruomi; Nomiyama, Tetsuo

2016-07-01

Students' depressive symptoms might be related to their own risk factors and to their parents' status. The objective of this cross-sectional study was to examine the relationship of depressive symptoms with lifestyle variables and parents' psychological and socio-demographic status among Japanese junior high school students. Of 477 students and their parents, 409 (85.7 %) students and 314 (65.8 %) parents participated in the study. Students answered self-reported questionnaire on depressive symptoms, their heights and weights, subjective stress, body dissatisfaction, lifestyles including sleep duration and extracurricular physical activity in school and other physical activity outside the school, and nutritional intake. Parents responded to questionnaire on depressive symptoms and socio-demographic status. The prevalence of depressive symptoms was 24.9 %. Students with depressive symptoms were more likely to have stress. Students in shorter and longer sleep duration groups were more likely to have depressive symptoms. The students with depressive symptoms had smaller amount of energy intake than did those without depressive symptoms. Multiple logistic regression analysis revealed significant relationships between students' depressive symptoms and some independent variables. Sex, subjective stress, "almost-never"-categorized extracurricular physical activity in school and other physical activity outside the school, and having a parent with depressive symptoms were significantly associated with students' depressive symptoms. Reducing mental stress and taking care of lifestyles, especially, "almost-everyday"-categorized extracurricular physical activity in school and other physical activity outside the school, may have benefits for students' mental health, and having a parent with depressive symptoms may be associated with students' depressive symptoms.

Physical activity level and its sociodemographic correlates in a peri-urban Nepalese population: a cross-sectional study from the Jhaukhel-Duwakot health demographic surveillance site.

PubMed

Vaidya, Abhinav; Krettek, Alexandra

2014-03-14

Physical inactivity is a leading risk factor for cardiovascular and other noncommunicable diseases in high-, low- and middle-income countries. Nepal, a low-income country in South Asia, is undergoing an epidemiological transition. Although the reported national prevalence of physical inactivity is relatively low, studies in urban and peri-urban localities have always shown higher prevalence. Therefore, this study aimed to measure physical activity in three domains-work, travel and leisure-in a peri-urban community and assess its variations across different sociodemographic correlates. Adult participants (n=640) from six randomly selected wards of the Jhaukhel-Duwakot Health Demographic Surveillance Site (JD-HDSS) near Kathmandu responded to the Global Physical Activity Questionnaire. To determine total physical activity, we calculated the metabolic equivalent of task in minutes/week for each domain and combined the results. Respondents were categorized into high, moderate or low physical activity. We also calculated the odds ratio for low physical activity in various sociodemographic variables and self-reported cardiometabolic states. The urbanizing JD-HDSS community showed a high prevalence of low physical activity (43.3%; 95% CI 39.4-47.1). Work-related activity contributed most to total physical activity. Furthermore, women and housewives and older, more educated and self-or government-employed respondents showed a greater prevalence of physical inactivity. Respondents with hypertension, diabetes or overweight/obesity reported less physical activity than individuals without those conditions. Only 5% of respondents identified physical inactivity as a cardiovascular risk factor. Our findings reveal a high burden of physical inactivity in a peri-urban community of Nepal. Improving the level of physical activity involves sensitizing people to its importance through appropriate multi-sector strategies that provide encouragement across all sociodemographic groups.

Design of quantum efficiency measurement system for variable doping GaAs photocathode

NASA Astrophysics Data System (ADS)

Chen, Liang; Yang, Kai; Liu, HongLin; Chang, Benkang

2008-03-01

To achieve high quantum efficiency and good stability has been a main direction to develop GaAs photocathode recently. Through early research, we proved that variable doping structure is executable and practical, and has great potential. In order to optimize variable doping GaAs photocathode preparation techniques and study the variable doping theory deeply, a real-time quantum efficiency measurement system for GaAs Photocathode has been designed. The system uses FPGA (Field-programmable gate array) device, and high speed A/D converter to design a high signal noise ratio and high speed data acquisition card. ARM (Advanced RISC Machines) core processor s3c2410 and real-time embedded system are used to obtain and show measurement results. The measurement precision of photocurrent could reach 1nA, and measurement range of spectral response curve is within 400~1000nm. GaAs photocathode preparation process can be real-time monitored by using this system. This system could easily be added other functions to show the physic variation of photocathode during the preparation process more roundly in the future.

Verifying and Validating Simulation Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hemez, Francois M.

2015-02-23

This presentation is a high-level discussion of the Verification and Validation (V&V) of computational models. Definitions of V&V are given to emphasize that “validation” is never performed in a vacuum; it accounts, instead, for the current state-of-knowledge in the discipline considered. In particular comparisons between physical measurements and numerical predictions should account for their respective sources of uncertainty. The differences between error (bias), aleatoric uncertainty (randomness) and epistemic uncertainty (ignorance, lack-of- knowledge) are briefly discussed. Four types of uncertainty in physics and engineering are discussed: 1) experimental variability, 2) variability and randomness, 3) numerical uncertainty and 4) model-form uncertainty. Statisticalmore » sampling methods are available to propagate, and analyze, variability and randomness. Numerical uncertainty originates from the truncation error introduced by the discretization of partial differential equations in time and space. Model-form uncertainty is introduced by assumptions often formulated to render a complex problem more tractable and amenable to modeling and simulation. The discussion concludes with high-level guidance to assess the “credibility” of numerical simulations, which stems from the level of rigor with which these various sources of uncertainty are assessed and quantified.« less

Physical Activity Patterns in the National Weight Control Registry

PubMed Central

Catenacci, Victoria A.; Ogden, Lorraine G.; Stuht, Jennifer; Phelan, Suzanne; Wing, Rena R.; Hill, James O.; Wyatt, Holly R.

2015-01-01

Objective The National Weight Control Registry (NWCR) was established in 1993 to examine the characteristics of those who are successful at weight loss: individuals maintaining a 13.6-kg weight loss for >1 year. The size of the registry has increased substantially since the early descriptions of this group a decade ago. The purpose of this study was to describe in detail the weekly physical activity habits of NWCR members, to examine the relationship between amount of activity and demographic characteristics, and to determine if changes in activity parameters have occurred over time. Methods and Procedures Participants were 887 men and 2,796 women who enrolled in the NWCR between 1993 and 2004. Physical activity was evaluated at registry entry using the Paffenbarger Physical Activity Questionnaire. Results NWCR entrants report an average of 2,621 ± 2,252 kcal/week in physical activity. There is considerable variability in the amount of activity reported: 25.3% report <1,000 kcal/week and 34.9% report >3,000 kcal/week. Activity level on registry entry is related to the magnitude but not the duration of weight loss. The amount of activity reported by men has decreased over time while no significant change was observed in women. Changes in the types of activities most frequently reported were also observed. Discussion Overall, NWCR participants are an extremely physically active group. However, the amount of activity reported is highly variable, making it difficult to develop a single recommendation for the optimum amount of physical activity for weight loss maintenance. A better understanding of individual-specific determinants of how much activity is required for weight loss maintenance ought to be a high research priority. PMID:18223628

Association between physiological falls risk and physical performance tests among community-dwelling older adults.

PubMed

Singh, Devinder K A; Pillai, Sharmila G K; Tan, Sin Thien; Tai, Chu Chiau; Shahar, Suzana

2015-01-01

Physical performance and balance declines with aging and may lead to increased risk of falls. Physical performance tests may be useful for initial fall-risk screening test among community-dwelling older adults. Physiological profile assessment (PPA), a composite falls risk assessment tool is reported to have 75% accuracy to screen for physiological falls risk. PPA correlates with Timed Up and Go (TUG) test. However, the association between many other commonly used physical performance tests and PPA is not known. The aim of the present study was to examine the association between physiological falls risk measured using PPA and a battery of physical performance tests. One hundred and forty older adults from a senior citizens club in Kuala Lumpur, Malaysia (94 females, 46 males), aged 60 years and above (65.77±4.61), participated in this cross-sectional study. Participants were screened for falls risk using PPA. A battery of physical performance tests that include ten-step test (TST), short physical performance battery (SPPB), functional reach test (FRT), static balance test (SBT), TUG, dominant hand-grip strength (DHGS), and gait speed test (GST) were also performed. Spearman's rank correlation and binomial logistic regression were performed to examine the significantly associated independent variables (physical performance tests) with falls risk (dependent variable). Approximately 13% older adults were at high risk of falls categorized using PPA. Significant differences (P<0.05) were demonstrated for age, TST, SPPB, FRT, SBT, TUG between high and low falls risk group. A significant (P<0.01) weak correlation was found between PPA and TST (r=0.25), TUG (r=0.27), SBT (r=0.23), SPPB (r=-0.33), and FRT (r=-0.23). Binary logistic regression results demonstrated that SBT measuring postural sways objectively using a balance board was the only significant predictor of physiological falls risk (P<0.05, odds ratio of 2.12). The reference values of physical performance tests in our study may be used as a guide for initial falls screening to categorize high and low physiological falls risk among community-dwelling older adults. A more comprehensive assessment of falls risk can be performed thereafter for more specific intervention of underlying impairments.

Academic Achievement in Physics-Chemistry: The Predictive Effect of Attitudes and Reasoning Abilities.

PubMed

Vilia, Paulo N; Candeias, Adelinda A; Neto, António S; Franco, Maria Da Glória S; Melo, Madalena

2017-01-01

Science education plays a critical role as political priority due to its fundamental importance in engaging students to pursue technological careers considered essential in modern societies, in order to face scientific development challenges. High-level achievement on science education and positive attitudes toward science constitutes a crucial challenge for formal education. Several studies indicate close relationships between students' attitudes, cognitive abilities, and academic achievement. The main purpose of this study is to analyze the impact of student's attitudes toward the school discipline of Physics and Chemistry and their reasoning abilities on academic achievement on that school subject, among Portuguese 9th grade students using the data collected during the Project Academic Performance and Development: a longitudinal study on the effects of school transitions in Portuguese students (PTDC/CPE-CED/104884/2008). The participants were 470 students (267 girls - 56.8% and 203 boys - 43.2%), aged 14-16 years old (μ = 14.3 ± 0.58). The attitude data were collected using the Attitude toward Physics-Chemistry Questionnaire (ATPCQ) and, the Reasoning Test Battery (RTB) was used to assess the students reasoning abilities. Achievement was measured using the students' quarterly (9-week) grades in the physics and chemistry subject. The relationships between the attitude dimensions toward Physics-chemistry and the reasoning dimensions and achievement in each of the three school terms were assessed by multiple regression stepwise analyses and standardized regression coefficients (β), calculated with IBM SPSS Statistics 21 software. Both variables studied proved to be significant predictor variables of school achievement. The models obtained from the use of both variables were always stronger accounting for higher proportions of student's grade variations. The results show that ATPCQ and RTB had a significantly positive relationship with student's achievement in Physics-chemistry, indicating that both attitudinal and cognitive variables should be taken into account on science education as well as in educative intervention.

Academic Achievement in Physics-Chemistry: The Predictive Effect of Attitudes and Reasoning Abilities

PubMed Central

Vilia, Paulo N.; Candeias, Adelinda A.; Neto, António S.; Franco, Maria Da Glória S.; Melo, Madalena

2017-01-01

Science education plays a critical role as political priority due to its fundamental importance in engaging students to pursue technological careers considered essential in modern societies, in order to face scientific development challenges. High-level achievement on science education and positive attitudes toward science constitutes a crucial challenge for formal education. Several studies indicate close relationships between students’ attitudes, cognitive abilities, and academic achievement. The main purpose of this study is to analyze the impact of student’s attitudes toward the school discipline of Physics and Chemistry and their reasoning abilities on academic achievement on that school subject, among Portuguese 9th grade students using the data collected during the Project Academic Performance and Development: a longitudinal study on the effects of school transitions in Portuguese students (PTDC/CPE-CED/104884/2008). The participants were 470 students (267 girls – 56.8% and 203 boys – 43.2%), aged 14–16 years old (μ = 14.3 ± 0.58). The attitude data were collected using the Attitude toward Physics-Chemistry Questionnaire (ATPCQ) and, the Reasoning Test Battery (RTB) was used to assess the students reasoning abilities. Achievement was measured using the students’ quarterly (9-week) grades in the physics and chemistry subject. The relationships between the attitude dimensions toward Physics-chemistry and the reasoning dimensions and achievement in each of the three school terms were assessed by multiple regression stepwise analyses and standardized regression coefficients (β), calculated with IBM SPSS Statistics 21 software. Both variables studied proved to be significant predictor variables of school achievement. The models obtained from the use of both variables were always stronger accounting for higher proportions of student’s grade variations. The results show that ATPCQ and RTB had a significantly positive relationship with student’s achievement in Physics-chemistry, indicating that both attitudinal and cognitive variables should be taken into account on science education as well as in educative intervention. PMID:28701978

Parallel structure among environmental gradients and three trophic levels in a subarctic estuary

USGS Publications Warehouse

Speckman, Suzann G.; Piatt, John F.; Minte-Vera, C. V.; Parrish, Julia K.

2005-01-01

We assessed spatial and temporal variability in the physical environment of a subarctic estuary, and examined concurrent patterns of chlorophyll α abundance (fluorescence), and zooplankton and forage fish community structure. Surveys were conducted in lower Cook Inlet, Alaska, during late July and early August from 1997 through 1999. Principle components analysis (PCA) revealed that spatial heterogeneity in the physical oceanographic environment of lower Cook Inlet could be modeled as three marine-estuarine gradients characterized by temperature, salinity, bottom depth, and turbidity. The gradients persisted from 1997 through 1999, and PCA explained 68% to 92% of the variance in physical oceanography for each gradient-year combination. Correlations between chlorophyll α abundance and distribution and the PCA axes were weak. Chlorophyll was reduced by turbidity, and low levels occurred in areas with high levels of suspended sediments. Detrended correspondence analysis (DCA) was used to order the sample sites based on species composition and to order the zooplankton and forage fish taxa based on similarities among sample sites for each gradient-year. Correlations between the structure of the physical environment (PCA axis 1) and zooplankton community structure (DCA axis 1) were strong (r = 0.43-0.86) in all years for the three marine-estuarine gradients, suggesting that zooplankton community composition was structured by the physical environment. The physical environment (PCA) and forage fish community structure (DCA) were weakly correlated in all years along Gradient 2, defined by halocline intensity and surface temperature and salinity, even though these physical variables were more important for defining zooplankton habitats. However, the physical environment (PCA) and forage fish community structure (DCA) were strongly correlated along the primary marine-estuarine gradient (#1) in 1997 (r = 0.87) and 1998 (r = 0.82). The correlation was poor (r = 0.32) in 1999, when fish community structure changed markedly in lower Cook Inlet. Capelin (Mallotus villosus), walleye pollock (Theragra chalcogramma), and arrowtooth flounder (Atheresthes stomias) were caught farther north than in previous years. Waters were significantly colder and more saline in 1999, a La Nina year, than in other years of the study. Interannual fluctuations in environmental conditions in lower Cook Inlet did not have substantial effects on zooplankton community structure, although abundance of individual taxa varied significantly. The abundance and distribution of chlorophyll α, zooplankton and forage fish were affected much more by spatial variability in physical oceanography than by interannual variability. Our examination of physical-biological linkages in lower Cook Inlet supports the concept of "bottom-up control," i.e., that variability in the physical environment structures higher trophic-level communities by influencing their distribution and abundance across space.

Parallel structure among environmental gradients and three trophic levels in a subarctic estuary

NASA Astrophysics Data System (ADS)

Speckman, Suzann G.; Piatt, John F.; Minte-Vera, Carolina V.; Parrish, Julia K.

2005-07-01

We assessed spatial and temporal variability in the physical environment of a subarctic estuary, and examined concurrent patterns of chlorophyll α abundance (fluorescence), and zooplankton and forage fish community structure. Surveys were conducted in lower Cook Inlet, Alaska, during late July and early August from 1997 through 1999. Principle components analysis (PCA) revealed that spatial heterogeneity in the physical oceanographic environment of lower Cook Inlet could be modeled as three marine-estuarine gradients characterized by temperature, salinity, bottom depth, and turbidity. The gradients persisted from 1997 through 1999, and PCA explained 68% to 92% of the variance in physical oceanography for each gradient-year combination. Correlations between chlorophyll α abundance and distribution and the PCA axes were weak. Chlorophyll was reduced by turbidity, and low levels occurred in areas with high levels of suspended sediments. Detrended correspondence analysis (DCA) was used to order the sample sites based on species composition and to order the zooplankton and forage fish taxa based on similarities among sample sites for each gradient-year. Correlations between the structure of the physical environment (PCA axis 1) and zooplankton community structure (DCA axis 1) were strong ( r = 0.43-0.86) in all years for the three marine-estuarine gradients, suggesting that zooplankton community composition was structured by the physical environment. The physical environment (PCA) and forage fish community structure (DCA) were weakly correlated in all years along Gradient 2, defined by halocline intensity and surface temperature and salinity, even though these physical variables were more important for defining zooplankton habitats. However, the physical environment (PCA) and forage fish community structure (DCA) were strongly correlated along the primary marine-estuarine gradient (#1) in 1997 ( r = 0.87) and 1998 ( r = 0.82). The correlation was poor ( r = 0.32) in 1999, when fish community structure changed markedly in lower Cook Inlet. Capelin ( Mallotus villosus), walleye pollock ( Theragra chalcogramma), and arrowtooth flounder ( Atheresthes stomias) were caught farther north than in previous years. Waters were significantly colder and more saline in 1999, a La Niña year, than in other years of the study. Interannual fluctuations in environmental conditions in lower Cook Inlet did not have substantial effects on zooplankton community structure, although abundance of individual taxa varied significantly. The abundance and distribution of chlorophyll α, zooplankton and forage fish were affected much more by spatial variability in physical oceanography than by interannual variability. Our examination of physical-biological linkages in lower Cook Inlet supports the concept of “bottom-up control,” i.e., that variability in the physical environment structures higher trophic-level communities by influencing their distribution and abundance across space.

Overview of the observations of symbiotic stars

NASA Technical Reports Server (NTRS)

Viotti, Roberto

1993-01-01

The term Symbiotic stars commonly denotes variable stars whose optical spectra simultaneously present a cool absorption spectrum (typically TiO absorption bands) and emission lines of high ionization energy. This term is now used for the category of variable stars with composite spectrum. The main spectral features of these objects are: (1) the presence of the red continuum typical of a cool star, (2) the rich emission line spectrum, and (3) the UV excess, frequently with the Balmer continuum in emission. In addition to the peculiar spectrum, the very irregular photometric and spectroscopic variability is the major feature of the symbiotic stars. Moreover, the light curve is basic to identify the different phases of activity in a symbiotic star. The physical mechanisms that cause the symbiotic phenomenon and its variety are the focus of this paper. An astronomical phenomenon characterized by a composite stellar spectrum with two apparently conflicting features, and large variability has been observed. Our research set out to find the origin of this behavior and, in particular, to identify and measure the physical mechanism(s) responsible for the observed phenomena.

High Frequency Radar Observations of Tidal Current Variability in the Lower Chesapeake Bay

NASA Astrophysics Data System (ADS)

Updyke, T. G.; Dusek, G.; Atkinson, L. P.

2016-02-01

Analysis of eight years of high frequency radar surface current observations in the lower Chesapeake Bay is presented with a focus on the variability of the tidal component of the surface circulation which accounts for a majority of the variance of the surface flow (typically 70-80% for the middle of the radar footprint). Variations in amplitude and phase of the major tidal constituents are examined in the context of water level, wind and river discharge data. Comparisons are made with harmonic analysis results from long-term records of current data measured by three current profilers operated by NOAA as part of the Chesapeake Bay Physical Oceanographic Real-Time System (PORTS). Preliminary results indicate that there is significant spatial variability in the M2 amplitude over the HF radar grid as well as temporal variability when harmonic analysis is performed using bi-monthly time segments over the course of the record.

First-Order Frameworks for Managing Models in Engineering Optimization

NASA Technical Reports Server (NTRS)

Alexandrov, Natlia M.; Lewis, Robert Michael

2000-01-01

Approximation/model management optimization (AMMO) is a rigorous methodology for attaining solutions of high-fidelity optimization problems with minimal expense in high- fidelity function and derivative evaluation. First-order AMMO frameworks allow for a wide variety of models and underlying optimization algorithms. Recent demonstrations with aerodynamic optimization achieved three-fold savings in terms of high- fidelity function and derivative evaluation in the case of variable-resolution models and five-fold savings in the case of variable-fidelity physics models. The savings are problem dependent but certain trends are beginning to emerge. We give an overview of the first-order frameworks, current computational results, and an idea of the scope of the first-order framework applicability.

Physical activity behaviour in men with inflammatory joint disease: a cross-sectional register-based study.

PubMed

Hammer, Nanna Maria; Midtgaard, Julie; Hetland, Merete Lund; Krogh, Niels Steen; Esbensen, Bente Appel

2018-05-01

Physical activity is recommended as an essential part of the non-pharmacological management of inflammatory joint disease, but previous research in this area has predominantly included women. The aim of this study was to examine physical activity behaviour in men with inflammatory joint disease. The study was conducted as a cross-sectional register-based study. Data on physical activity behaviour in men with RA, PsA and AS were matched with sociodemographic and clinical variables extracted from the DANBIO registry. Logistic regression analyses using multiple imputations were performed to investigate demographic and clinical variables associated with regular engagement in physical activity (moderate-vigorous ⩾2 h/week). Descriptive statistics were applied to explore motivation, barriers and preferences for physical activity. A total of 325 men were included of whom 129 (40%) engaged in regular physical activity. In univariate analyses, higher age, visual analogue scale (VAS) for pain, VAS fatigue, VAS patient's global, CRP level, disease activity, functional disability and current smoking were negatively associated with regular engagement in physical activity. In the final multivariable regression model only a high VAS fatigue score (⩾61 mm) (OR = 0.228; CI: 0.119, 0.436) remained significantly independently associated with regular physical activity. A majority of men with inflammatory joint disease do not meet the recommendations of regular physical activity. Both sociodemographic and clinical parameters were associated with engagement in physical activity, and fatigue especially seems to play a pivotal role in explaining suboptimal physical activity behaviour in this patient group.

To twist, roll, stroke or poke? A study of input devices for menu navigation in the cockpit.

PubMed

Stanton, Neville A; Harvey, Catherine; Plant, Katherine L; Bolton, Luke

2013-01-01

Modern interfaces within the aircraft cockpit integrate many flight management system (FMS) functions into a single system. The success of a user's interaction with an interface depends upon the optimisation between the input device, tasks and environment within which the system is used. In this study, four input devices were evaluated using a range of Human Factors methods, in order to assess aspects of usability including task interaction times, error rates, workload, subjective usability and physical discomfort. The performance of the four input devices was compared using a holistic approach and the findings showed that no single input device produced consistently high performance scores across all of the variables evaluated. The touch screen produced the highest number of 'best' scores; however, discomfort ratings for this device were high, suggesting that it is not an ideal solution as both physical and cognitive aspects of performance must be accounted for in design. This study evaluated four input devices for control of a screen-based flight management system. A holistic approach was used to evaluate both cognitive and physical performance. Performance varied across the dependent variables and between the devices; however, the touch screen produced the largest number of 'best' scores.

Reanalysis of Water, Land Use, and Production Data for Assessing China's Agricultural Resources

NASA Astrophysics Data System (ADS)

Smith, T.; Pan, J.; McLaughlin, D.

2016-12-01

Quantitative data about water availability, crop evapotranspiration (ET), agricultural land use, and production are needed at high temporal and spatial resolutions to develop sustainable water and agricultural plan and policies. However, large-scale high-resolution measured data can be susceptible to errors, physically inconsistent, or incomplete. Reanalysis provides a way to develop improved physically consistent estimates of both measured and hidden variables. The reanalysis approach described here uses a least-squares technique constrained by water balances and crop water requirements to assimilate many possibly redundant data sources to yield estimates of water, land use, and food production variables that are physically consistent while minimizing differences from measured data. As an example, this methodology is applied in China, where food demand is expected to increase but land and water resources could constrain further increases in food production. Hydrologic fluxes, crop ET, agricultural land use, yields, and food production are characterized at 0.5o by 0.5o resolution for a nominal year around the year 2000 for 22 different crop groups. The reanalysis approach provides useful information for resource management and policy, both in China and around the world.

Cardiorespiratory fitness in males, and upper limbs muscular strength in females, are positively related with 25-hydroxyvitamin D plasma concentrations in European adolescents: the HELENA study.

PubMed

Valtueña, J; Gracia-Marco, L; Huybrechts, I; Breidenassel, C; Ferrari, M; Gottrand, F; Dallongeville, J; Sioen, I; Gutierrez, A; Kersting, M; Kafatos, A; Manios, Y; Widhalm, K; Moreno, L A; González-Gross, M

2013-09-01

High prevalence of vitamin D insufficiency (<75 nmol/l) has been previously reported in European adolescents. Vitamin D deficiency has been related to physical fitness and adiposity but it is not clearly known whether this relationship applies to growing children and adolescents. To determine how body composition and physical fitness are related to 25-hydroxyvitamin D [25(OH)D] concentrations in European adolescents. The HEalthy Lifestyle in Europe by Nutrition in Adolescence-CSS study was a multi-centre cross-sectional study. Plasma 25(OH)D, body composition and physical fitness measures were obtained in 1006 European adolescents (470 males) aged 12.5-17.5 years. Stepwise regression and ANCOVA were performed by gender using 25(OH)D as dependent variable, with body composition, physical fitness as independent variables controlling for age, seasonality and latitude. For males, maximum oxygen consumption (VO2max) (B = 0.189) and body mass index (BMI) (B = -0.124) were independently associated with 25(OH)D concentrations (both P < 0.05). For females, handgrip strength (B = 0.168; P < 0.01) was independently associated with 25(OH)D concentrations. Those adolescents at lower BMI and high fitness score presented significant higher 25(OH)D concentrations than those at lower fitness score in the other BMI groups (P < 0.05). Cardiorespiratory fitness and upper limbs muscular strength are positively associated with 25(OH)D concentrations in male and female adolescents, respectively. Adiposity in males and low fat free mass in females are related to hypovitaminosis D. The interaction between fitness and BMI has a positive effect on 25(OH)D concentrations. Therapeutic interventions to correct the high rates of vitamin D deficiency in adolescents should consider physical fitness.

Physical fitness, health behaviour and health among nursing students: A descriptive correlational study.

PubMed

Klainin-Yobas, Piyanee; He, Hong-Gu; Lau, Ying

2015-12-01

Health behaviour is of great importance for nursing students to achieve optimal health. Healthy students tend to complete their study and remain in the nursing workforce. They will also serve as a role model of for patients. However, there is limited research concerning physical fitness and health behaviour (such as sleep problems) in this population. This study aims to examine the relationships among health behaviour, personal variables, physical fitness, perceived physical health and psychological health. A cross-sectional descriptive correlational study was used. A total of 335 nursing students who were enrolled in a university in Thailand. Data were collected by self-administered questionnaires and physical fitness tests. Independent variables were personal variables and health behaviour. Outcome variables included physical fitness, perceived physical health and psychological health. Descriptive statistics and path analyses were used to analyse data. Nursing students had poor to moderate levels of total physical fitness, with cardiovascular fitness and body flexibility components having the lowest scores. Students who exercised regularly tended to have better physical fitness, perceived physical health and psychological health. Those who did not have sleep problems had better psychological health. Some personal variables and health behaviours were associated with health among nursing students. Appropriate interventions are required to promote positive health behaviour in this population. Copyright © 2015 Elsevier Ltd. All rights reserved.

Parenting styles and hormone levels as predictors of physical and indirect aggression in boys and girls.

PubMed

Pascual-Sagastizabal, Eider; Azurmendi, Aitziber; Braza, Francisco; Vergara, Ana I; Cardas, Jaione; Sánchez-Martín, José R

2014-01-01

This study examines the relationship between parenting style, androgen levels, and measures of physical and indirect aggression. Peer ratings of aggression were obtained from 159 eight-year-old children (89 boys and 70 girls). Parenting styles (authoritative, authoritarian or permissive) were assessed using the Parenting Styles and Dimensions Questionnaire (PSDQ).Saliva samples were obtained from children and assayed for testosterone and androstenedione concentrations. A regression analysis revealed that high testosterone levels were associated with a higher level of physical aggression in boys with authoritarian mothers. Testosterone was also found to moderate the relationship between father's authoritarian parenting and physical aggression in girls, with both moderate and high levels being significant. In relation to indirect aggression, moderate and high levels of testosterone were associated with higher levels of this type of aggression in girls with permissive mothers. Our results highlight the importance of taking into account the interaction of biological and psychosocial variables when investigating aggressive behavior. © 2014 Wiley Periodicals, Inc.

Using Atmospheric Circulation Patterns to Detect and Attribute Changes in the Risk of Extreme Climate Events

NASA Astrophysics Data System (ADS)

Diffenbaugh, N. S.; Horton, D. E.; Singh, D.; Swain, D. L.; Touma, D. E.; Mankin, J. S.

2015-12-01

Because of the high cost of extreme events and the growing evidence that global warming is likely to alter the statistical distribution of climate variables, detection and attribution of changes in the probability of extreme climate events has become a pressing topic for the scientific community, elected officials, and the public. While most of the emphasis has thus far focused on analyzing the climate variable of interest (most often temperature or precipitation, but also flooding and drought), there is an emerging emphasis on applying detection and attribution analysis techniques to the underlying physical causes of individual extreme events. This approach is promising in part because the underlying physical causes (such as atmospheric circulation patterns) can in some cases be more accurately represented in climate models than the more proximal climate variable (such as precipitation). In addition, and more scientifically critical, is the fact that the most extreme events result from a rare combination of interacting causes, often referred to as "ingredients". Rare events will therefore always have a strong influence of "natural" variability. Analyzing the underlying physical mechanisms can therefore help to test whether there have been changes in the probability of the constituent conditions of an individual event, or whether the co-occurrence of causal conditions cannot be distinguished from random chance. This presentation will review approaches to applying detection/attribution analysis to the underlying physical causes of extreme events (including both "thermodynamic" and "dynamic" causes), and provide a number of case studies, including the role of frequency of atmospheric circulation patterns in the probability of hot, cold, wet and dry events.

Capacity for Physical Activity Predicts Weight Loss After Roux-en-Y Gastric Bypass

PubMed Central

Hatoum, Ida J.; Stein, Heather K.; Merrifield, Benjamin F.; Kaplan, Lee M.

2014-01-01

Despite its overall excellent outcomes, weight loss after Roux-en-Y gastric bypass (RYGB) is highly variable. We conducted this study to identify clinical predictors of weight loss after RYGB. We reviewed charts from 300 consecutive patients who underwent RYGB from August 1999 to November 2002. Data collected included patient demographics, medical comorbidities, and diet history. Of the 20 variables selected for univariate analysis, 9 with univariate P values ≤ 0.15 were entered into a multivariable regression analysis. Using backward selection, covariates with P < 0.05 were retained. Potential confounders were added back into the model and assessed for effect on all model variables. Complete records were available for 246 of the 300 patients (82%). The patient characteristics were 75% female, 93% white, mean age of 45 years, and mean initial BMI of 52.3 kg/m2. One year after surgery, patients lost an average of 64.8% of their excess weight (s.d. = 20.5%). The multivariable regression analysis revealed that limited physical activity, higher initial BMI, lower educational level, diabetes, and decreased attendance at postoperative appointments had an adverse effect on weight loss after RYGB. A model including these five factors accounts for 41% of the observed variability in weight loss (adjusted r2 = 0.41). In this cohort, higher initial BMI and limited physical activity were the strongest predictors of decreased excess weight loss following RYGB. Limited physical activity may be particularly important because it represents an opportunity for potentially meaningful pre- and postsurgical intervention to maximize weight loss following RYGB. PMID:18997674

Unforced decadal fluctuations in a coupled model of the atmosphere and ocean mixed layer

NASA Technical Reports Server (NTRS)

Barnett, T. P.; Del Genio, A. D.; Ruedy, R. A.

1992-01-01

Global average temperature in a 100-year control run of a model used for greenhouse gas response simulations showed low-frequency natural variability comparable in magnitude to that observed over the last 100 years. The model variability was found to be barotropic in the atmosphere, and located in the tropical strip with largest values near the equator in the Pacific. The model variations were traced to complex, low-frequency interactions between the meridional sea surface temperature gradients in the eastern equatorial Pacific, clouds at both high and low levels, and features of the tropical atmospheric circulation. The variations in these and other model parameters appear to oscillate between two limiting climate states. The physical scenario accounting for the oscillations on decadal time scales is almost certainly not found in the real world on shorter time scales due to limited resolution and the omission of key physics (e.g., equatorial ocean dynamics) in the model. The real message is that models with dynamical limitations can still produce significant long-term variability. Only a thorough physical diagnosis of such simulations and comparisons with decadal-length data sets will allow one to decide if faith in the model results is, or is not, warranted.

Does high diurnal variability in a reef flat from Ofu, American Samoa confer resistance to ocean acidification?

NASA Astrophysics Data System (ADS)

Koweek, D.; Samuel, L.; Mucciarone, D. A.; Woodson, C. B.; Monismith, S. G.; Dunbar, R. B.

2012-12-01

Forecasts for coral reefs under various ocean acidification scenarios are becoming increasingly complex due to significant inter-site variability in biogeochemistry, ecology, and physical oceanography. The reef flats of Ofu, American Samoa are a potential end-member of this vulnerability spectrum due to extremely high diurnal variability in their biogeochemistry. Here we present coupled biogeochemical and physical oceanographic measurements from a shallow reef flat on Ofu in November 2011. We observed diurnal temperature ranges of up to 7°C, along with diurnal pH and dissolved oxygen ranges of 0.6 units, and 160 percent of saturation, respectively. Carbon system measurements were less extreme. Alkalinity varied between 2240-2360 μmol/kg and total dissolved inorganic carbon (TDIC) ranged between 1850-2100 μmol/kg during the diurnal cycle. These observations suggest diurnal ranges of ~240ppm CO2 and 1.5 units of ΩAr. The larger diurnal range in TDIC relative to alkalinity suggests a reef environment dominated by photosynthesis. From these observations, we explore the balance between the dominant biogeochemical processes of production and calcification on the reef flat in more detail, along with its implication for conferring resistance to ocean acidification. We use calcification rate estimates to provide insight to patterns of day and night growth and/or dissolution on the reef. Finally, we present evidence of tidal modulation of the biogeochemical signals and discuss the role of localized physical circulation in helping to determine a reef's vulnerability to ocean acidification.

Exploring the impacts of physics and resolution on aqua-planet simulations from a nonhydrostatic global variable-resolution modeling framework: IMPACTS OF PHYSICS AND RESOLUTION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Chun; Leung, L. Ruby; Park, Sang-Hun

Advances in computing resources are gradually moving regional and global numerical forecasting simulations towards sub-10 km resolution, but global high resolution climate simulations remain a challenge. The non-hydrostatic Model for Prediction Across Scales (MPAS) provides a global framework to achieve very high resolution using regional mesh refinement. Previous studies using the hydrostatic version of MPAS (H-MPAS) with the physics parameterizations of Community Atmosphere Model version 4 (CAM4) found notable resolution dependent behaviors. This study revisits the resolution sensitivity using the non-hydrostatic version of MPAS (NH-MPAS) with both CAM4 and CAM5 physics. A series of aqua-planet simulations at global quasi-uniform resolutionsmore » ranging from 240 km to 30 km and global variable resolution simulations with a regional mesh refinement of 30 km resolution over the tropics are analyzed, with a primary focus on the distinct characteristics of NH-MPAS in simulating precipitation, clouds, and large-scale circulation features compared to H-MPAS-CAM4. The resolution sensitivity of total precipitation and column integrated moisture in NH-MPAS is smaller than that in H-MPAS-CAM4. This contributes importantly to the reduced resolution sensitivity of large-scale circulation features such as the inter-tropical convergence zone and Hadley circulation in NH-MPAS compared to H-MPAS. In addition, NH-MPAS shows almost no resolution sensitivity in the simulated westerly jet, in contrast to the obvious poleward shift in H-MPAS with increasing resolution, which is partly explained by differences in the hyperdiffusion coefficients used in the two models that influence wave activity. With the reduced resolution sensitivity, simulations in the refined region of the NH-MPAS global variable resolution configuration exhibit zonally symmetric features that are more comparable to the quasi-uniform high-resolution simulations than those from H-MPAS that displays zonal asymmetry in simulations inside the refined region. Overall, NH-MPAS with CAM5 physics shows less resolution sensitivity compared to CAM4. These results provide a reference for future studies to further explore the use of NH-MPAS for high-resolution climate simulations in idealized and realistic configurations.« less

Children's Attitudes toward Physical Activity and Self-Esteem.

ERIC Educational Resources Information Center

Ewy, Stan R.

This study was conducted to investigate attitudes toward physical activity and self-esteem of students (N=82) in grades three through five. The independent variables were gender, grade placement, and physical fitness. The dependent variables were scores from the Grade 3 Children's Attitudes Toward Physical Activity, the Revised Children's…

A church-based intervention to change attitudes about physical activity among Black adolescent girls: a feasibility study.

PubMed

Thompson, Wanda M; Berry, Diane; Hu, Jie

2013-05-01

To feasibility test a 12-week church-based physical activity intervention that was culturally sensitive, age- and gender specific directed at changing attitudes of Black adolescent girls' to be more physically active. A one-group pre- and posttest design was used. A convenience sample of Black adolescent girls between the age of 12-18 (n = 41). A 60-min 12-week church-based program that included interactive educational sessions followed by a high energy dance aerobics class was used. Data were collected on biophysical measures. Surveys were used to assess the following variables: attitudes, enjoyment, self-efficacy, intention, social and family support, and PA levels. Paired t-tests and repeated measures ANOVA revealed no significant changes in key variables. Positive changes were noted in the odds ratios for attitudes, self-efficacy, and intention. Body mass index, metabolic equivalent tasks, and fitness showed positive trends from pre to post intervention. Family support was significantly correlated with physical activity level (p < .01). The study showed that physical activity programs in Black churches aimed at Black adolescent girls are feasible. Participants evaluated the intervention very favorably. Family support may be a key factor in increasing physical activity levels in Black adolescent girls. © 2012 Wiley Periodicals, Inc.

An evaluation of the effects of bed rest, sleep deprivation and discontinuance of training on the physical fitness of highly trained young men

NASA Technical Reports Server (NTRS)

Olree, H. D.; Corbin, B.; Dugger, G.; Smith, C.

1973-01-01

This experiment was conducted to determine what physiological effects result when highly trained subjects are confined to bed, deprived of sleep, or allowed to discontinue training. Results indicated: (1) There was a moderate increase in strength variables due to the training in this experiment but the stress which the subjects received caused a negligible change in strength variables. (2) The training program resulted in highly significant changes in specific bicycle ergometer variables indicating good increases in cardiopulmonary fitness. Five days of bed rest or fifty hours of sleep deprivation caused comparable drastic decreases in cardiopulmonary fitness. Post stress the subjects reverted to a normal daily schedule and after two weeks they had recovered about half of what they lost. (3) Cardiac output remains relatively constant at a constant work load, but stroke volume increases with conditioning and decreases with deconditioning due to stress.

Factors associated with BMI, underweight, overweight, and obesity among adults in a population of rural south India: a cross-sectional study.

PubMed

Little, Matthew; Humphries, Sally; Patel, Kirit; Dewey, Cate

2016-01-01

Overweight, obesity, and related chronic diseases are becoming serious public health concerns in rural areas of India. Compounded with the existing issue of underweight, such concerns expose the double burden of disease and may put stress on rural healthcare. The purpose of this article was to present the prevalence and factors associated with underweight, overweight, and obesity in an area of rural south India. During 2013 and 2014, a random sample of adults aged 20-80 years were selected for participation in a cross-sectional study that collected information on diet (using a food frequency questionnaire), physical activity (using the Global Physical Activity Questionnaire), socioeconomic position (using a wealth index), rurality (using the MSU rurality index), education, and a variety of descriptive factors. BMI was measured using standard techniques. Using a multivariate linear regression analysis and multivariate logistic regression analyses, we examined associations between BMI, overweight, obesity, and underweight, and all potential risk factors included in the survey. Age and sex-adjusted prevalence of overweight, obesity class I, and obesity class II were 14.9, 16.1, and 3.3 % respectively. Prevalence of underweight was 22.7 %. The following variables were associated with higher BMI and/or increased odds of overweight, obesity class I, and/or obesity class II: Low physical activity, high wealth index, no livestock, low animal fat consumption, high n-6 polyunsaturated fat consumption, television ownership, time spent watching television, low rurality index, and high caste. The following variables were associated with increased odds of underweight: low wealth index, high rurality index, and low intake of n-6 PUFAs. Underweight, overweight, and obesity are prevalent in rural regions of southern India, indicating a village-level dual burden. A variety of variables are associated with these conditions, including physical activity, socioeconomic position, rurality, television use, and diet. To address the both underweight and obesity, policymakers must simultaneously focus on encouraging positive behaviour through education and addressing society-level risk factors that inhibit individuals from achieving optimal health.

Effects of Timber Harvest on River Food Webs: Physical, Chemical and Biological Responses

PubMed Central

Wootton, J. Timothy

2012-01-01

I compared physical, chemical and biological characteristics of nine rivers running through three timber harvest regimes to investigate the effects of land use on river ecosystems, to determine whether these corresponded to changes linked with downstream location, and to compare the response of different types of indicator variables. Physical variables changed with downstream location, but varied little with timber harvest. Most chemical variables increased strongly with timber harvest, but not with downstream location. Most biological variables did not vary systematically with either timber harvst or downstream location. Dissolved organic carbon did not vary with timber harvest or downstream location, but correlated positively with salmonid abundance. Nutrient manipulations revealed no general pattern of nutrient limitation with timber harvest or downstream location. The results suggest that chemical variables most reliably indicate timber harvest impact in these systems. The biological variables most relevant to human stakeholders were surprisingly insensitive to timber harvest, however, apparently because of decoupling from nutrient responses and unexpectedly weak responses by physical variables. PMID:22957030

Body composition and physical fitness in women with bulimia nervosa or binge-eating disorder.

PubMed

Mathisen, Therese Fostervold; Rosenvinge, Jan H; Friborg, Oddgeir; Pettersen, Gunn; Stensrud, Trine; Hansen, Bjørge Herman; Underhaug, Karoline E; Teinung, Elisabeth; Vrabel, KariAnne; Svendsen, Mette; Bratland-Sanda, Solfrid; Sundgot-Borgen, Jorunn

2018-04-01

Knowledge about physical fitness in women with bulimia nervosa (BN) or binge-eating disorder (BED) is sparse. Previous studies have measured physical activity largely through self-report, and physical fitness variables are mainly restricted to body mass index (BMI) and bone mineral density. We expanded the current knowledge in these groups by including a wider range of physical fitness indicators and objective measures of physical activity, assessed the influence of a history of anorexia nervosa (AN), and evaluated predictive variables for physical fitness. Physical activity, blood pressure, cardiorespiratory fitness (CRF), muscle strength, body composition, and bone mineral density were measured in 156 women with BN or BED, with mean (SD) age 28.4 years (5.7) and BMI 25.3 (4.8) kg m -2 . Level of physical activity was higher than normative levels, still <50% met the official physical activity recommendation. Fitness in women with BN were on an average comparable with recommendations or normative levels, while women with BED had lower CRF and higher BMI, VAT, and body fat percentage. We found 10-12% with masked obesity. A history of AN did not predict current physical fitness, still values for current body composition were lower when comparing those with history of AN to those with no such history. Overall, participants with BN or BED displayed adequate physical fitness; however, a high number had unfavorable CRF and body composition. This finding calls for inclusion of physical fitness in routine clinical examinations and guided physical activity and dietary recommendations in the treatment of BN and BED. © 2018 The Authors International Journal of Eating Disorders Published by Wiley Periodicals, Inc.

Predicting climate effects on Pacific sardine

PubMed Central

Deyle, Ethan R.; Fogarty, Michael; Hsieh, Chih-hao; Kaufman, Les; MacCall, Alec D.; Munch, Stephan B.; Perretti, Charles T.; Ye, Hao; Sugihara, George

2013-01-01

For many marine species and habitats, climate change and overfishing present a double threat. To manage marine resources effectively, it is necessary to adapt management to changes in the physical environment. Simple relationships between environmental conditions and fish abundance have long been used in both fisheries and fishery management. In many cases, however, physical, biological, and human variables feed back on each other. For these systems, associations between variables can change as the system evolves in time. This can obscure relationships between population dynamics and environmental variability, undermining our ability to forecast changes in populations tied to physical processes. Here we present a methodology for identifying physical forcing variables based on nonlinear forecasting and show how the method provides a predictive understanding of the influence of physical forcing on Pacific sardine. PMID:23536299

Gender Inequality in the Couple Relationship and Leisure-Based Physical Exercise.

PubMed

Annandale, Ellen; Hammarström, Anne

2015-01-01

To analyse whether gender inequality in the couple relationship was related to leisure-based physical activity, after controlling for earlier physical activity and confounders. Data drawn from the Northern Swedish Cohort of all pupils in their final year of compulsory schooling in a town in the North of Sweden. The sample consisted of 772 respondents (n = 381 men, n = 391 women) in the 26-year follow-up (in 2007, aged 42) who were either married or cohabiting. Ordinal regression, for men and women separately, was used to assess the association between gender inequality (measured as self-perceived equality in the couple relationship using dummy variables) and a measure of exercise frequency, controlling for prior exercise frequency, socioeconomic status, the presence of children in the home, and longer than usual hours in paid work. The perception of greater gender equality in the couple relationship was associated with higher levels of physical activity for both men and women. This remained significant when the other variables were controlled for. Amongst men the confidence intervals were high. The results point to the potential of perceived gender equality in the couple relationship to counteract the general time poverty and household burden that often arises from the combination of paid work and responsibility for children and the home, especially for women. The high confidence intervals among men indicate the need for more research within the field with larger samples.

Motivation in High School Science Students: A Comparison of Gender Differences in Life, Physical, and Earth Science Classes

ERIC Educational Resources Information Center

Britner, Shari L.

2008-01-01

The aims of this study were to examine self-efficacy and other motivation variables among high school science students (n = 502); to determine the degree to which each of the four hypothesized sources of self-efficacy makes an independent contribution to students' science self-efficacy beliefs; to examine possible differences between life,…

Psychological theory in an interdisciplinary context: psychological, demographic, health-related, social, and environmental correlates of physical activity in a representative cohort of community-dwelling older adults.

PubMed

Sniehotta, Falko F; Gellert, Paul; Witham, Miles D; Donnan, Peter T; Crombie, Iain K; McMurdo, Marion E T

2013-09-08

Physical activity (PA) in older adults is influenced by a range of environmental, demographic, health-related, social, and psychological variables. Social cognitive psychological models assume that all influences on behaviour operate indirectly through the models constructs, i.e., via intention and self-efficacy. We evaluated direct, indirect, and moderating relationships of a broad range of external variables with physical activity levels alongside intention and self-efficacy. We performed a cross-sectional survey of a representative and stratified (65-80 and 80+ years; deprived and affluent) sample of 584 community-dwelling people, resident in Scotland. Objectively measured physical activity and questionnaire data were collected. Self-efficacy showed unique relationships with physical activity, controlling for demographic, mental health, social, environmental, and weather variables separately, but the relationship was not significant when controlling for physical health. Overall, results indicating support for a mediation hypothesis, intention and self-efficacy statistically mediate the relationship of most domain variables with physical activity. Moderation analyses show that the relationship between social cognitions and physical activity was stronger for individuals with better physical health and lower levels of socio-economic deprivation. Social cognitive variables reflect a range of known environmental, demographic, health-related and social correlates of physical activity, they mediate the relationships of those correlates with physical activity and account for additional variance in physical activity when external correlates are controlled for, except for the physical health domain. The finding that the social cognition-physical activity relationship is higher for participants with better health and higher levels of affluence raises issues for the applicability of social cognitive models to the most disadvantaged older people.

Changes in heart rate variability are associated with expression of short-term and long-term contextual and cued fear memories.

PubMed

Liu, Jun; Wei, Wei; Kuang, Hui; Zhao, Fang; Tsien, Joe Z

2013-01-01

Heart physiology is a highly useful indicator for measuring not only physical states, but also emotional changes in animals. Yet changes of heart rate variability during fear conditioning have not been systematically studied in mice. Here, we investigated changes in heart rate and heart rate variability in both short-term and long-term contextual and cued fear conditioning. We found that while fear conditioning could increase heart rate, the most significant change was the reduction in heart rate variability which could be further divided into two distinct stages: a highly rhythmic phase (stage-I) and a more variable phase (stage-II). We showed that the time duration of the stage-I rhythmic phase were sensitive enough to reflect the transition from short-term to long-term fear memories. Moreover, it could also detect fear extinction effect during the repeated tone recall. These results suggest that heart rate variability is a valuable physiological indicator for sensitively measuring the consolidation and expression of fear memories in mice.

Characteristics of 'tween' participants and non-participants in the VERB™ summer scorecard physical activity promotion program.

PubMed

Nickelson, Jen; Alfonso, Moya L; McDermott, Robert J; Bumpus, Elizabeth C; Bryant, Carol A; Baldwin, Julie A

2011-04-01

Creating community-based opportunities for youth to be physically active is challenging for many municipalities. A Lexington, Kentucky community coalition designed and piloted a physical activity program, 'VERB™ summer scorecard (VSS)', leveraging the brand equity of the national VERB™--It's What You Do! campaign. Key elements of VSS subsequently were adopted in Sarasota County, FL. This study identified characteristics of Sarasota's VSS participants and non-participants. Students in Grades 5-8 from six randomly selected public schools completed a survey assessing VSS participation, physical activity level, psychosocial variables, parental support for physical activity and demographics. Logistic regression showed that VSS participants were more likely to be from Grades 5 to 6 versus Grades 7 and 8 [odds ratio (OR) = 6.055] and perceive high versus low parental support for physical activity (OR = 4.627). Moreover, for each unit rise in self-efficacy, the odds of VSS participation rose by 1.839. Chi-squared automatic interaction detector (CHAID) analysis suggested an interaction effect between grade and school socioeconomic status (SES), with a large proportion of seventh and eighth graders from high SES schools being non-participants (76.6%). A VSS-style program can be expected to be more effective with tweens who are younger, in a middle SES school, having high self-efficacy and high parental support for physical activity.

Assessment of co-composting process with high load of an inorganic industrial waste.

PubMed

Soares, Micaela A R; Quina, Margarida J; Reis, Marco S; Quinta-Ferreira, Rosa

2017-01-01

This study aims to investigate the co-composting of an inorganic industrial waste (eggshell - ES) in very high levels (up to 60% w/w). Since composting is a process in which solid, liquid and gaseous phases interact in a very complex way, there is a need to shed light on statistical tools that can unravel the main relationships structuring the variability associated to this process. In this study, PCA and data visualisation were used with that purpose. The co-composting tests were designed with increasing quantities of ES (0, 10, 20, 30 and 60%ES w/w) mixed with industrial potato peel and rice husks. Principal component analysis showed that physical properties like free air space, bulk density and moisture are the most relevant variables for explaining the variability due to ES content. On the other hand, variability in time dynamics is mostly driven by some chemical and phytoxicological parameters, such as organic matter decay and nitrate content. Higher ES incorporation (60% ES) enhanced the initial biological activity of the mixture, but the higher bulk density and lower water holding capacity had a negative effect on the aerobic biological activity as the process evolved. Nevertheless, pathogen-killing temperatures (>70°C for 11h) were attained. All the final products obtained after 90days were stable and non-phytotoxic. This work proved that valorisation of high amounts of eggshell by co-composting is feasible, but prone to be influenced by the physical properties of the mixtures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kepler and K2 Light Curves of Active Galaxies: Optical Time Domain Windows into the Central Engine

NASA Astrophysics Data System (ADS)

Smith, Krista Lynne; Mushotzky, Richard; Boyd, Patricia T.; Howell, Steve B.; Gehrels, Neil; Gelino, Dawn M.

2017-01-01

We have used the Kepler spacecraft, the most precise photometer ever built, to measure aperiodic variability in active galactic nuclei. Kepler's high cadence and even sampling make it an exquisite instrument for astrophysics far beyond exoplanets, especially in the study of active galactic nuclei, which have long been known for their strong optical variability. Because of the very small size of accretion disks, this variability provides the only direct probe of their interior physics. In order to find AGN for study with the Kepler and K2 missions, we have conducted an X-ray survey of the Kepler and K2 fields of view with the Swift XRT, locating hundreds of new AGN that sample a wide parameter space in black hole mass and accretion rate. This survey also yielded an abundant sample of X-ray bright variable stellar targets. We then built a custom pipeline to handle Kepler light curves of extended objects (the AGN host galaxies) with stochastic variability. This was necessary, since the default Kepler pipeline was not optimized for such objects. Power spectral density (PSD) analysis of the AGN light curves exhibit characteristic timescales on the order of 2.5 days to 80 days, consistent with the physical timescales believed to be important in the disk. Optical spectral follow-up of the full sample enables comparison with physical parameters such as black hole mass, Eddington ratio and bolometric luminosity. The black hole mass relationship with characteristic timescale is consistent with an extrapolation of the relationship seen in stellar mass black holes, implying accretion similarities across many orders of magnitude. One object hosts a strong candidate for an optical quasi-periodic oscillation (QPO), the characteristic frequency of which correctly predicts the measured single-epoch black hole mass. The sample also contains bimodal flux distributions, which may indicate accretion states. Many of the high-frequency power spectral density (PSD) slopes are generally consistent with damped random walk models, but these fail to describe the full range of variability observed. The light curves continue to provide a fertile testing bed for the various predictions of accretion disk simulations.

Intraindividual variability in physical and emotional functioning: comparison of adults with traumatic brain injuries and healthy adults.

PubMed

Burton, Catherine L; Hultsch, David F; Strauss, Esther; Hunter, Michael A

2002-08-01

Recent research has shown that individuals with certain neurological conditions demonstrate greater intraindividual variability on cognitive tasks compared to healthy controls. The present study investigated intraindividual variability in the domains of physical functioning and affect/stress in three groups: adults with mild head injuries, adults with moderate/severe head injuries, and healthy adults. Participants were assessed on 10 occasions and results indicated that (a) individuals with head injuries demonstrated greater variability in dominant finger dexterity and right grip strength than the healthy controls; (b) increased variability tended to be associated with poorer performance/report both within and across tasks; and (c) increased variability on one task was associated with increased variability on other tasks. The findings suggest that increased variability in physical function, as well as cognitive function, represents an indicator of neurological compromise.

Drought vulnerability assessment of maize in Sub-Saharan Africa: Insights from physical and social perspectives

NASA Astrophysics Data System (ADS)

Kamali, Bahareh; Abbaspour, Karim C.; Wehrli, Bernhard; Yang, Hong

2018-03-01

Drought as a slow-onset phenomenon inflicts important losses to agriculture where the degree of vulnerability depends not only on physical variables such as precipitation and temperature, but also on societal preparedness. While the scopes of physical and social vulnerability are very different in nature, studies distinguishing these two aspects have been lacking. In this study we address the physical and social aspects of drought vulnerability of maize (CDVIphy and CDVIsoc) in Sub-Saharan Africa (SSA). To quantify vulnerability, we applied a probabilistic framework combining a Drought Exposure Index (DEI) with a physical or social Crop Failure Index, CFIphy or CFIsoc, respectively. DEI was derived from the exceedance probability of precipitation. Maize yields, simulated using the Environmental Policy Integrated Climate (EPIC) model, were used to build CFIphy, whereas the residual of simulated and FAO recorded yields were used to construct CFIsoc. The results showed that southern and partially central Africa are more vulnerable to physical drought as compared to other regions. Central and western Africa, however, are socially highly vulnerable. Comparison of CDVIphy and CDVIsoc revealed that societal factors cause more vulnerability than physical variables in almost all SSA countries except Nigeria and South Africa. We conclude that quantification of both drought vulnerabilities help a better characterization of droughts and identify regions where more investments in drought preparedness are required.

Novel Design of a Soft Lightweight Pneumatic Continuum Robot Arm with Decoupled Variable Stiffness and Positioning.

PubMed

Giannaccini, Maria Elena; Xiang, Chaoqun; Atyabi, Adham; Theodoridis, Theo; Nefti-Meziani, Samia; Davis, Steve

2018-02-01

Soft robot arms possess unique capabilities when it comes to adaptability, flexibility, and dexterity. In addition, soft systems that are pneumatically actuated can claim high power-to-weight ratio. One of the main drawbacks of pneumatically actuated soft arms is that their stiffness cannot be varied independently from their end-effector position in space. The novel robot arm physical design presented in this article successfully decouples its end-effector positioning from its stiffness. An experimental characterization of this ability is coupled with a mathematical analysis. The arm combines the light weight, high payload to weight ratio and robustness of pneumatic actuation with the adaptability and versatility of variable stiffness. Light weight is a vital component of the inherent safety approach to physical human-robot interaction. To characterize the arm, a neural network analysis of the curvature of the arm for different input pressures is performed. The curvature-pressure relationship is also characterized experimentally.

Novel Design of a Soft Lightweight Pneumatic Continuum Robot Arm with Decoupled Variable Stiffness and Positioning

PubMed Central

Xiang, Chaoqun; Atyabi, Adham; Theodoridis, Theo; Nefti-Meziani, Samia; Davis, Steve

2018-01-01

Abstract Soft robot arms possess unique capabilities when it comes to adaptability, flexibility, and dexterity. In addition, soft systems that are pneumatically actuated can claim high power-to-weight ratio. One of the main drawbacks of pneumatically actuated soft arms is that their stiffness cannot be varied independently from their end-effector position in space. The novel robot arm physical design presented in this article successfully decouples its end-effector positioning from its stiffness. An experimental characterization of this ability is coupled with a mathematical analysis. The arm combines the light weight, high payload to weight ratio and robustness of pneumatic actuation with the adaptability and versatility of variable stiffness. Light weight is a vital component of the inherent safety approach to physical human-robot interaction. To characterize the arm, a neural network analysis of the curvature of the arm for different input pressures is performed. The curvature-pressure relationship is also characterized experimentally. PMID:29412080

Genetic risk for neurodegenerative disorders, and its overlap with cognitive ability and physical function.

PubMed

Hagenaars, Saskia P; Radaković, Ratko; Crockford, Christopher; Fawns-Ritchie, Chloe; Harris, Sarah E; Gale, Catharine R; Deary, Ian J

2018-01-01

Neurodegenerative disorders are associated with impaired cognitive function and worse physical health outcomes. This study aims to test whether polygenic risk for Alzheimer's disease, Amyotrophic Lateral Sclerosis (ALS), or frontotemporal dementia (FTD) is associated with cognitive function and physical health in the UK Biobank, a cohort of healthy individuals. Group-based analyses were then performed to compare the top and bottom 10% for the three neurodegenerative polygenic risk scores; these groups were compared on the cognitive and physical health variables. Higher polygenic risk for AD, ALS, and FTD was associated with lower cognitive performance. Higher polygenic risk for FTD was also associated with increased forced expiratory volume in 1s and peak expiratory flow. A significant group difference was observed on the symbol digit substitution task between individuals with high polygenic risk for FTD and high polygenic risk for ALS. The results suggest some overlap between polygenic risk for neurodegenerative disorders, cognitive function and physical health.

A model independent search for new physics in final states containing leptons at the DO experiment

NASA Astrophysics Data System (ADS)

Piper, Joel M.

The standard model is known to be the low energy limit of a more general theory. Several consequences of the standard model point to a strong probability of new physics becoming experimentally visible in high energy collisions of a few TeV, resulting in high momentum objects. The specific signatures of these collisions are topics of much debate. Rather than choosing a specific signature, this analysis broadly searches the data, preferring breadth over sensitivity. In searching for new physics, several different approaches are used. These include the comparison of data with standard model background expectation in overall number of events, comparisons of distributions of many kinematic variables, and finally comparisons on the tails of distributions that sum the momenta of the objects in an event. With 1.07 fb-1 at the DO experiment, we find no evidence of physics beyond the standard model. Several discrepancies from the standard model were found, but none of these provide a compelling case for new physics.

Factors associated with physical violence against pregnant women from São Luís, Maranhão State, Brazil: an approach using structural equation modeling.

PubMed

Costa, Danielle Cristina Silva; Ribeiro, Marizélia Rodrigues Costa; Batista, Rosângela Fernandes Lucena; Valente, Camila Maia; Ribeiro, João Victor Fonseca; Almeida, Laysa Andrade; Costa, Ludmilla Emilia Martins; Alves, Maria Teresa Seabra Soares de Britto E; Silva, Antônio Augusto Moura da

2017-01-23

The factors associated with physical violence against pregnant women were analyzed in a cross-sectional study of 1,446 pregnant women from a prenatal cohort who were interviewed in 2010 and 2011 in São Luís, Brazil. In the initial model, socioeconomic status occupied the most distal position, determining sociodemographic factors, social support and the behavioral factors that ultimately determined physical violence, which was investigated as a latent variable. Structural equation modeling was used in the analysis. Pregnant women who were from more disadvantaged backgrounds (p = 0.027), did not reside with intimate partners (p = 0.005), had low social support (p < 0.001) and had a high number of lifetime intimate partners (p = 0.001) reported more episodes of physical violence. Low social support was the primary mediator of the effect of socioeconomic status on physical violence. The effect of marital status was mainly mediated by a high number of lifetime intimate partners.

Physically Active Adults: An Analysis of the Key Variables That Keep Them Moving

ERIC Educational Resources Information Center

Downs, Andrew

2016-01-01

Background: A large proportion of adults are insufficiently physically active, and researchers have yet to determine the factors that enable individuals to maintain adequate levels of physical activity throughout adulthood. Purpose: This study sought to identify the key variables linked with consistent physical activity in adulthood as elucidated…

Nature of global large-scale sea level variability in relation to atmospheric forcing: A modeling study

NASA Astrophysics Data System (ADS)

Fukumori, Ichiro; Raghunath, Ramanujam; Fu, Lee-Lueng

1998-03-01

The relation between large-scale sea level variability and ocean circulation is studied using a numerical model. A global primitive equation model of the ocean is forced by daily winds and climatological heat fluxes corresponding to the period from January 1992 to January 1994. The physical nature of sea level's temporal variability from periods of days to a year is examined on the basis of spectral analyses of model results and comparisons with satellite altimetry and tide gauge measurements. The study elucidates and diagnoses the inhomogeneous physics of sea level change in space and frequency domain. At midlatitudes, large-scale sea level variability is primarily due to steric changes associated with the seasonal heating and cooling cycle of the surface layer. In comparison, changes in the tropics and high latitudes are mainly wind driven. Wind-driven variability exhibits a strong latitudinal dependence in itself. Wind-driven changes are largely baroclinic in the tropics but barotropic at higher latitudes. Baroclinic changes are dominated by the annual harmonic of the first baroclinic mode and is largest off the equator; variabilities associated with equatorial waves are smaller in comparison. Wind-driven barotropic changes exhibit a notable enhancement over several abyssal plains in the Southern Ocean, which is likely due to resonant planetary wave modes in basins semienclosed by discontinuities in potential vorticity. Otherwise, barotropic sea level changes are typically dominated by high frequencies with as much as half the total variance in periods shorter than 20 days, reflecting the frequency spectra of wind stress curl. Implications of the findings with regards to analyzing observations and data assimilation are discussed.

Variable X-Ray Absorption in the Mini-BAL QSO PG 1126-041

NASA Technical Reports Server (NTRS)

Giustini, M.; Cappi, M.; Chartas, G.; Dadina, M.; Eracleous, M.; Ponti, G.; Proga, D.; Tombesi, F.; Vignali, C.; Palumbo, G. G. C.

2011-01-01

Context. X-ray studies of AGN with powerful nuclear winds are important to constrain the physics of the inner accretion/ejection flow around SMBH, and to understand the impact of such winds on the AGN environment. Aims. Our main scientific goal is to constrain the properties of a variable outflowing absorber that is thought to be launched near the SMBH of the mini-BAL QSO PG 1126-041 using a multi-epoch observational campaign performed with XMM-Newton. Methods. We performed temporally resolved X-ray spectroscopy and simultaneous UV and X-ray photometry on the most complete set of observations and on the deepest X-ray exposure of a mini-BAL QSO to date. Results. We found complex X-ray spectral variability on time scales of both months and hours, best reproduced by means of variable massive ionized absorbers along the line of sight. As a consequence, the observed optical-to-X-ray spectral index is found to be variable with time. In the highest signal-to-noise observation we detected highly ionized X-ray absorbing material outflowing much faster (u(sub X) approx. 16 500 km/s) than the UV absorbing one (u(sub uv) approx. 5,000 km/s). This highly ionized absorber is found to be variable on very short (a few kiloseconds) time scales. Conclusions. Our findings are qualitatively consistent with line driven accretion disk winds scenarios. Our observations have opened the time-resolved X-ray spectral analysis field for mini-BAL QSOs; only with future deep studies will we be able to map the dynamics of the inner flow and understand the physics of AGN winds and their impact on the environment.

Physical Performance Measures Associated With Locomotive Syndrome in Middle-Aged and Older Japanese Women.

PubMed

Nakamura, Misa; Hashizume, Hiroshi; Oka, Hiroyuki; Okada, Morihiro; Takakura, Rie; Hisari, Ayako; Yoshida, Munehito; Utsunomiya, Hirotoshi

2015-01-01

The Japanese Orthopaedic Association proposed a concept called locomotive syndrome (LS) to identify middle-aged and older adults at high risk of requiring health care services because of problems with locomotion. It is important to identify factors associated with the development of LS. Physical performance measures such as walking speed and standing balance are highly predictive of subsequent disability and mortality in older adults. However, there is little evidence about the relationship between physical performance measures and LS. To determine the physical performance measures associated with LS, the threshold values for discriminating individuals with and without LS, and the odds ratio of LS according to performance greater than or less than these thresholds in middle-aged and older Japanese women. Participants were 126 Japanese women (mean age = 61.8 years). Locomotive syndrome was defined as a score of 16 or more on the 25-question Geriatric Locomotive Function Scale. Physical performance was evaluated using grip strength, unipedal stance time with eyes open, seated toe-touch, and normal and fast 6-m walk time (6 MWT). Variables were compared between LS and non-LS groups. Fourteen participants (11.1%) were classed as having LS. Unipedal stance time, normal 6 MWT, and fast 6 MWT were significantly different between the 2 groups. The LS group had a shorter unipedal stance time and a longer normal and fast 6 MWT than the non-LS group. For these 3 variables, the area under the receiver operating characteristic curve was greater than 0.7, and the threshold for discriminating the non-LS and LS groups was 15 s for unipedal stance time, 4.8 s for normal 6 MWT and 3.6 s for fast 6 MWT. These variables were entered into a multiple logistic regression analysis, which indicated that unipedal stance time less than 15 s was significantly related to LS (odds ratio = 8.46; P < .01). Unipedal stance time was the physical performance measure that was most strongly associated with LS. This measure may be useful for early detection of LS.

Neighborhood disorder and screen time among 10-16 year old Canadian youth: A cross-sectional study

PubMed Central

2012-01-01

Background Screen time activities (e.g., television, computers, video games) have been linked to several negative health outcomes among young people. In order to develop evidence-based interventions to reduce screen time, the factors that influence the behavior need to be better understood. High neighborhood disorder, which may encourage young people to stay indoors where screen time activities are readily available, is one potential factor to consider. Methods Results are based on 15,917 youth in grades 6-10 (aged 10-16 years old) who participated in the Canadian 2009/10 Health Behaviour in School-aged Children Survey (HBSC). Total hours per week of television, video games, and computer use were reported by the participating students in the HBSC student questionnaire. Ten items of neighborhood disorder including safety, neighbors taking advantage, drugs/drinking in public, ethnic tensions, gangs, crime, conditions of buildings/grounds, abandoned buildings, litter, and graffiti were measured using the HBSC student questionnaire, the HBSC administrator questionnaire, and Geographic Information Systems. Based upon these 10 items, social and physical neighborhood disorder variables were derived using principal component analysis. Multivariate multilevel logistic regression analyses were used to examine the relationship between social and physical neighborhood disorder and individual screen time variables. Results High (top quartile) social neighborhood disorder was associated with approximately 35-45% increased risk of high (top quartile) television, computer, and video game use. Physical neighborhood disorder was not associated with screen time activities after adjusting for social neighborhood disorder. However, high social and physical neighborhood disorder combined was associated with approximately 40-60% increased likelihood of high television, computer, and video game use. Conclusion High neighborhood disorder is one environmental factor that may be important to consider for future public health interventions and strategies aiming to reduce screen time among youth. PMID:22651908

The Association between Belgian Older Adults' Physical Functioning and Physical Activity: What Is the Moderating Role of the Physical Environment?

PubMed

Van Holle, Veerle; Van Cauwenberg, Jelle; Gheysen, Freja; Van Dyck, Delfien; Deforche, Benedicte; Van de Weghe, Nico; De Bourdeaudhuij, Ilse

2016-01-01

Better physical functioning in the elderly may be associated with higher physical activity levels. Since older adults spend a substantial part of the day in their residential neighborhood, the neighborhood physical environment may moderate associations between functioning and older adults' physical activity. The present study investigated the moderating role of the objective and perceived physical environment on associations between Belgian older adults' physical functioning and transport walking, recreational walking, and moderate-to-vigorous physical activity. Data from 438 older adults were included. Objective physical functioning was assessed using the Short Physical Performance Battery. Potential moderators included objective neighborhood walkability and perceptions of land use mix diversity, access to recreational facilities, access to services, street connectivity, physical barriers for walking, aesthetics, crime-related safety, traffic speeding-related safety, and walking infrastructure. Transport and recreational walking were self-reported, moderate-to-vigorous physical activity was assessed through accelerometers. Multi-level regression analyses were conducted using MLwiN to examine two-way interactions between functioning and the environment on both walking outcomes. Based on a previous study where environment x neighborhood income associations were found for Belgian older adults' moderate-to-vigorous physical activity, three-way functioning x environment x income interactions were examined for moderate-to-vigorous physical activity. Objectively-measured walkability moderated the association between functioning and transport walking; this positive association was only present in high-walkable neighborhoods. Moreover, a three-way interaction was observed for moderate-to-vigorous physical activity. Only in high-income, high-walkable neighborhoods, there was a positive association between functioning and moderate-to-vigorous physical activity. No functioning x walkability interactions were observed for recreational walking, and none of the perceived environmental variables moderated the positive association between physical functioning and the physical activity outcomes. For older adults with better physical functioning, living in a high-walkable neighborhood could be beneficial to engage in more transport walking. Living in high-income, high-walkable neighborhoods and having better functioning might also be beneficial for more engagement in moderate-to-vigorous physical activity. This might suggest a protective role of neighborhood walkability for preventing declining physical functioning and consequently decreasing physical activity levels in older adults. However, given the cross-sectional design of the present study, this suggestion needs to be confirmed through longitudinal assessment investigating over-time changes in the observed associations.

Epidemiology of leisure, transportation, occupational, and household physical activity: prevalence and associated factors.

PubMed

Florindo, Alex Antonio; Guimarães, Vanessa Valente; Cesar, Chester Luiz Galvão; Barros, Marilisa Berti de Azevedo; Alves, Maria Cecília Goi Porto; Goldbaum, Moisés

2009-09-01

To estimate the prevalence of and identify factors associated with physical activity in leisure, transportation, occupational, and household settings. This was a cross-sectional study aimed at investigating living and health conditions among the population of São Paulo, Brazil. Data on 1318 adults aged 18 to 65 years were used. To assess physical activity, the long version of the International Physical Activity Questionnaire was applied. Multivariate analysis was conducted using a hierarchical model. The greatest prevalence of insufficient activity related to transportation (91.7%), followed by leisure (77.5%), occupational (68.9%), and household settings (56.7%). The variables associated with insufficient levels of physical activity in leisure were female sex, older age, low education level, nonwhite skin color, smoking, and self-reported poor health; in occupational settings were female sex, white skin color, high education level, self-reported poor health, nonsmoking, and obesity; in transportation settings were female sex; and in household settings, with male sex, separated, or widowed status and high education level. Physical activity in transportation and leisure settings should be encouraged. This study will serve as a reference point in monitoring different types of physical activities and implementing public physical activity policies in developing countries.

Temporal and vertical variability in optical properties of New England shelf waters during late summer and spring

NASA Astrophysics Data System (ADS)

Sosik, Heidi M.; Green, Rebecca E.; Pegau, W. Scott; Roesler, Collin S.

2001-05-01

Relationships between optical and physical properties were examined on the basis of intensive sampling at a site on the New England continental shelf during late summer 1996 and spring 1997. During both seasons, particles were found to be the primary source of temporal and vertical variability in optical properties since light absorption by dissolved material, though significant in magnitude, was relatively constant. Within the particle pool, changes in phytoplankton were responsible for much of the observed optical variability. Physical processes associated with characteristic seasonal patterns in stratification and mixing contributed to optical variability mostly through effects on phytoplankton. An exception to this generalization occurred during summer as the passage of a hurricane led to a breakdown in stratification and substantial resuspension of nonphytoplankton particulate material. Prior to the hurricane, conditions in summer were highly stratified with subsurface maxima in absorption and scattering coefficients. In spring, stratification was much weaker but increased over the sampling period, and a modest phytoplankton bloom caused surface layer maxima in absorption and scattering coefficients. These seasonal differences in the vertical distribution of inherent optical properties were evident in surface reflectance spectra, which were elevated and shifted toward blue wavelengths in the summer. Some seasonal differences in optical properties, including reflectance spectra, suggest that a significant shift toward a smaller particle size distribution occurred in summer. Shorter timescale optical variability was consistent with a variety of influences including episodic events such as the hurricane, physical processes associated with shelfbreak frontal dynamics, biological processes such as phytoplankton growth, and horizontal patchiness combined with water mass advection.

Stride dynamics, gait variability and prospective falls risk in active community dwelling older women.

PubMed

Paterson, Kade; Hill, Keith; Lythgo, Noel

2011-02-01

Measures of walking instability such as stride dynamics and gait variability have been shown to identify future fallers in older adult populations with gait limitations or mobility disorders. This study investigated whether measures of walking instability can predict future fallers (over a prospective 12 month period) in a group of healthy and active older women. Ninety-seven healthy active women aged between 55 and 90 years walked for 7 min around a continuous walking circuit. Gait data recorded by a GAITRite(®) walkway and foot-mounted accelerometers were used to calculate measures of stride dynamics and gait variability. The participant's physical function and balance were assessed. Fall incidence was monitored over the following 12 months. Inter-limb differences (p≤0.04) in stride dynamics were found for fallers (one or more falls) aged over 70 years, and multiple fallers (two or more falls) aged over 55 years, but not in non-fallers or a combined group of single and non-fallers. No group differences were found in the measures of physical function, balance or gait, including variability. Additionally, no gait variable predicted falls. Reduced coordination of inter-limb dynamics was found in active healthy older fallers and multiple fallers despite no difference in other measures of intrinsic falls risk. Evaluating inter-limb dynamics may be a clinically sensitive technique to detect early gait instability and falls risk in high functioning older adults, prior to change in other measures of physical function, balance and gait. Copyright © 2010 Elsevier B.V. All rights reserved.

Biobehavioral Triggers of Cardiac Arrhythmia during Daily Life: The Role of Emotion, Physical Activity, and Heart Rate Variability

DTIC Science & Technology

2004-01-01

chronically reduced HRV (e.g., Kawachi, et al, 1995). Heart rate variability among individuals without psychopathology, but with high levels of trait anxiety ...Figure 1.) After controlling for ejection fraction, anxiety scores remained predictive of all of the aforementioned measures of HRV (VLF r = -.49, p...associated with any measure of HRV (r = .07 to -.30, p = .80 to .26). Results regarding anxiety and HRV were unchanged after analyzing participants with

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeffries, H P

The principal hypothesis addressed in this study states that community variability is related to fatty acid structure. As a test of this idea, the zooplankton in three regimes of increasing physical severity (Block Island Sound, Narragansett Bay and Green Hill Pond) are being compared. Measurements were made on the physical environment, on standing crop and on fatty acid composition in both the phytoplankton-microzooplankton and macrozooplankton. Fatty acid variation in these communities displays a unique trajectory in time at each location. Environmental change and biochemical variability are directly related. The resulting biochemical message is complex but apparently highly informative. Patterns ofmore » variation in some fatty acids are affected most strongly by physical environmental parameters whereas the variation of other fatty acids is more responsive to differences in species composition, diversity and food web relationships. Taken together, these two aspects of biochemical pattern appear to characterize complex species assemblages. The result offers a new strategem for convenient assessment of the ever changing state in a natural community.« less

City scale pollen concentration variability

NASA Astrophysics Data System (ADS)

van der Molen, Michiel; van Vliet, Arnold; Krol, Maarten

2016-04-01

Pollen are emitted in the atmosphere both in the country-side and in cities. Yet the majority of the population is exposed to pollen in cities. Allergic reactions may be induced by short-term exposure to pollen. This raises the question how variable pollen concentration in cities are in temporally and spatially, and how much of the pollen in cities are actually produced in the urban region itself. We built a high resolution (1 × 1 km) pollen dispersion model based on WRF-Chem to study a city's pollen budget and the spatial and temporal variability in concentration. It shows that the concentrations are highly variable, as a result of source distribution, wind direction and boundary layer mixing, as well as the release rate as a function of temperature, turbulence intensity and humidity. Hay Fever Forecasts based on such high resolution emission and physical dispersion modelling surpass traditional hay fever warning methods based on temperature sum methods. The model gives new insights in concentration variability, personal and community level exposure and prevention. The model will be developped into a new forecast tool to serve allergic people to minimize their exposure and reduce nuisance, coast of medication and sick leave. This is an innovative approach in hay fever warning systems.

The relationship between quality of life and physical fitness in people with severe mental illness.

PubMed

Perez-Cruzado, D; Cuesta-Vargas, A I; Vera-Garcia, E; Mayoral-Cleries, F

2018-05-02

Quality of life of people with severe mental illness may be decrease by the high occurrence of metabolic and cardiovascular diseases. Physical fitness emerges as a modifying factor in this population through physical activity and this modification could influence in the quality of life of this population. The aim of the present study is to determine the contribution of physical fitness to the quality of life of people with severe mental illness. In the current study, a physiotherapist and an occupational therapist assessed 62 people with severe mental illness. Physical fitness was measured with a range of 11 fitness tests that covered flexibility, strength, balance, and endurance. To assess quality of life the EQ-5D-3 L scale was used, which measures five dimensions (mobility, self-care, usual activities, pain-discomfort, and anxiety-depression). Significant correlations are presented between the quality of life and primary variables of physical fitness (balance, endurance, and upper limb strength). Endurance explained 22.9% of the variance of the quality of life in people with severe mental illness. Functional reach added another 36.2% variance to the prediction of quality of life. The results of the present study suggest that some variables of physical fitness are associated with quality of life in people with severe mental illness. The improvement in physical fitness of this population should be a primary objective. ClinicalTrials.gov Identifier: NCT02413164 "retrospective registered" Registered Febr 2017.

Comparative analysis of female physicists in the physical sciences: Motivation and background variables

NASA Astrophysics Data System (ADS)

Dabney, Katherine P.; Tai, Robert H.

2014-06-01

The majority of existing science, technology, engineering, and mathematics (STEM) research studies compare women to men, yet a paucity of research exists that examines what differentiates female career choice within the physical sciences. In light of these research trends and recommendations, this study examines the following question: On average, do females who select physics as compared to chemistry doctoral programs differ in their reported personal motivations and background factors prior to entering the field? This question is analyzed using variables from the Project Crossover Survey data set through a subset of female physical science doctoral students and scientists (n =1137). A logistic regression analysis and prototypical odds ratio uncover what differentiates women in the physical sciences based on their academic achievement and experiences ranging from high school through undergraduate education. Results indicate that females who have negative undergraduate chemistry experiences as well as higher grades and positive experiences in undergraduate physics are more likely to pursue a career in physics as opposed to chemistry. Conclusions suggest that a greater emphasis should be placed on the classroom experiences that are provided to females in gateway physics courses. Analyses show that women are not a single entity that should only be examined as a whole group or in comparison to men. Instead women can be compared to one another to see what influences their differences in educational experiences and career choice in STEM-based fields as well as other academic areas of study.

Environmental and psychosocial correlates of objectively measured physical activity among older adults.

PubMed

Fleig, Lena; Ashe, Maureen C; Voss, Christine; Therrien, Suzanne; Sims-Gould, Joanie; McKay, Heather A; Winters, Meghan

2016-12-01

Neighborhood environments can support or hinder physical activity especially as health declines with age. This study puts psychological theories of health behavior change in context with built environment research to better understand the interplay of environmental and psychosocial characteristics impacting older adults' sedentary behavior and physical activity. The Active Streets, Active People study recruited 193 older adults living in a highly walkable neighborhood in Vancouver, British Columbia, Canada. Participants completed questionnaires on attitudes toward walking, behavioral control for walking, and perceived built environment variables. To assess behavior, participants wore an ActiGraph GT3X + accelerometer for 7 consecutive days. Regression-based path analysis was conducted to examine whether the link between the perceived environment and behavior is mediated by psychosocial variables. In total, 174 participants had valid accelerometry data (Mage = 70.3, SD = 7.2) and demonstrated a daily average of 525.7 min of sedentary behavior (SD = 65.1) as well as high levels of total physical activity (M = 254.3, SD = 65.1 min/day). Mediation analysis revealed that perceived street connectivity and diversity of land use were negatively related to sedentary behavior, but only indirectly through behavioral control. Similarly, effects of street connectivity and diversity of land use on physical activity were mediated by behavioral control. Results highlighted that the perceived built environment is important for physical activity and sedentary behavior, largely because these environmental perceptions are positively linked to older adults' confidence in walking. By integrating environmental and psychosocial correlates of preventive health behaviors within a theoretical structure, the psychosocial mechanisms through which the environment affects activity can be better understood. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Economic Evaluation and Transferability of Physical Activity Programmes in Primary Prevention: A Systematic Review

PubMed Central

Wolfenstetter, Silke B.; Wenig, Christina M.

2010-01-01

This systematic review aims to assess the characteristics of, and the clinical and economic evidence provided by, economic evaluations of primary preventive physical exercise interventions, and to analyse their transferability to Germany using recommended checklists. Fifteen economic evaluations from seven different countries met eligibility criteria, with seven of the fifteen providing high economic evidence in the special country context. Most of the identified studies conclude that the investigated intervention provide good value for money compared with alternatives. However, this review shows a high variability of the costing methods between the studies, which limits comparability, generalisability and transferability of the results. PMID:20617050

Development of students' interest in particle physics as effect of participating in a Masterclass

NASA Astrophysics Data System (ADS)

Gedigk, Kerstin; Pospiech, Gesche

2016-05-01

The International Hands On Particle Physics Masterclasses are enjoying increasing popularity worldwide every year. In Germany a national program was brought to live in 2010, which offers these appreciated events to whole classes or courses of high school students all over the year. These events were evaluated concerning the issues of students' interest in particle physics and their perception of the events. How several interest variables interact with each other and the perception of the events is answered by structural equation modelling (sect. 5.2). The results give information about the events' effects on the students' interest development in particle physics, show which event features are important ( e.g. the authenticity) and give information about practical approaches to improve the effects of the Masterclasses. Section 5.3 deals with a group of participants which have a high interest in particle physics 6-8 weeks after the participation. The number of these students is remarkable large, with 26% of all participants. The investigation of this group shows that the Masterclass participation has the same positive effect on both sexes and all levels of physics education.

Personality and physical functioning among older adults: the moderating role of education.

PubMed

Jaconelli, Alban; Stephan, Yannick; Canada, Brice; Chapman, Benjamin P

2013-07-01

Drawing upon a vulnerability model, this study tested whether low educational level would amplify the negative contribution of risky personality traits, such as high neuroticism and low conscientiousness, on older adults physical functioning. Five hundred and thirteen French-speaking community-dwelling older adults aged 60-91 years (mean age = 66.37, SD = 5.32) completed measures of physical functioning, education, personality traits, chronic conditions, and demographic variables. Results revealed that extraversion and conscientiousness were positively associated with physical functioning, whereas neuroticism was a negative predictor, beyond demographics, chronic conditions, and education. The negative relationship between neuroticism and physical functioning was stronger among individuals with low educational level and was nonsignificant among older people with higher level of education. This study is the first to support a vulnerability model, which entails an amplification of neuroticism risk at low education, but a diminishment of neuroticism risk for activity limitations at high education. As a whole, it appears that a focus on either personality or education without taking into account each other provides only a partial account of the predictors of basic daily physical activities in old age.

An issue encountered in solving problems in electricity and magnetism: curvilinear coordinates

NASA Astrophysics Data System (ADS)

Gülçiçek, Çağlar; Damlı, Volkan

2016-11-01

In physics lectures on electromagnetic theory and mathematical methods, physics teacher candidates have some difficulties with curvilinear coordinate systems. According to our experience, based on both in-class interactions and teacher candidates’ answers in test papers, they do not seem to have understood the variables in curvilinear coordinate systems very well. For this reason, the problems that physics teacher candidates have with variables in curvilinear coordinate systems have been selected as a study subject. The aim of this study is to find the physics teacher candidates’ problems with determining the variables of drawn shapes, and problems with drawing shapes based on given variables in curvilinear coordinate systems. Two different assessment tests were used in the study to achieve this aim. The curvilinear coordinates drawing test (CCDrT) was used to discover their problems related to drawing shapes, and the curvilinear coordinates detection test (CCDeT) was used to find out about problems related to determining variables. According to the findings obtained from both tests, most physics teacher candidates have problems with the ϕ variable, while they have limited problems with the r variable. Questions that are mostly answered wrongly have some common properties, such as value. According to inferential statistics, there is no significant difference between the means of the CCDeT and CCDrT scores. The mean of the CCDeT scores is only 4.63 and the mean of the CCDrT is only 4.66. Briefly, we can say that most physics teacher candidates have problems with drawing a shape using the variables of curvilinear coordinate systems or in determining the variables of drawn shapes. Part of this study was presented at the XI. National Science and Mathematics Education Congress (UFBMEK) in 2014.

Physical associations to spring phytoplankton biomass interannual variability in the U.S. Northeast Continental Shelf

NASA Astrophysics Data System (ADS)

Saba, Vincent S.; Hyde, Kimberly J. W.; Rebuck, Nathan D.; Friedland, Kevin D.; Hare, Jonathan A.; Kahru, Mati; Fogarty, Michael J.

2015-02-01

The continental shelf of the Northeast United States and Nova Scotia is a productive marine ecosystem that supports a robust biomass of living marine resources. Understanding marine ecosystem sensitivity to changes in the physical environment can start with the first-order response of phytoplankton (i.e., chlorophyll a), the base of the marine food web. However, the primary physical associations to the interannual variability of chlorophyll a in these waters are unclear. Here we used ocean color satellite measurements and identified the local and remote physical associations to interannual variability of spring surface chlorophyll a from 1998 to 2013. The highest interannual variability of chlorophyll a occurred in March and April on the northern flank of Georges Bank, the western Gulf of Maine, and Nantucket Shoals. Complex interactions between winter wind speed over the Shelf, local winter water levels, and the relative proportions of Atlantic versus Labrador Sea source waters entering the Gulf of Maine from the previous summer/fall were associated with the variability of March/April chlorophyll a in Georges Bank and the Gulf of Maine. Sea surface temperature and sea surface salinity were not robust correlates to spring chlorophyll a. Surface nitrate in the winter was not a robust correlate to chlorophyll a or the physical variables in every case suggesting that nitrate limitation may not be the primary constraint on the interannual variability of the spring bloom throughout all regions. Generalized linear models suggest that we can resolve 88% of March chlorophyll a interannual variability in Georges Bank using lagged physical data.

An elevated level of physical activity is associated with normal lipoprotein(a) levels in individuals from Maracaibo, Venezuela.

PubMed

Bermúdez, Valmore; Aparicio, Daniel; Rojas, Edward; Peñaranda, Lianny; Finol, Freddy; Acosta, Luis; Mengual, Edgardo; Rojas, Joselyn; Arráiz, Nailet; Toledo, Alexandra; Colmenares, Carlos; Urribarí, Jesica; Sanchez, Wireynis; Pineda, Carlos; Rodriguez, Dalia; Faria, Judith; Añez, Roberto; Cano, Raquel; Cano, Clímaco; Sorell, Luis; Velasco, Manuel

2010-01-01

Coronary artery disease is the main cause of death worldwide. Lipoprotein(a) [Lp(a)], is an independent risk factor for coronary artery disease in which concentrations are genetically regulated. Contradictory results have been published about physical activity influence on Lp(a) concentration. This research aimed to determine associations between different physical activity levels and Lp(a) concentration. A descriptive and cross-sectional study was made in 1340 randomly selected subjects (males = 598; females = 712) to whom a complete clinical history, the International Physical Activity Questionnaire, and Lp(a) level determination were made. Statistical analysis was carried out to assess qualitative variables relationship by chi2 and differences between means by one-way analysis of variance considering a P value <0.05 as statistically significant. Results are shown as absolute frequencies, percentages, and mean +/- standard deviation according to case. Physical activity levels were ordinal classified as follows: low activity with 24.3% (n = 318), moderate activity with 35.0% (n = 458), and high physical activity with 40.8% (n = 534). Lp(a) concentration in the studied sample was 26.28 +/- 12.64 (IC: 25.59-26.96) mg/dL. Lp(a) concentration according to low, moderate, and high physical activity levels were 29.22 +/- 13.74, 26.27 +/- 12.91, and 24.53 +/- 11.35 mg/dL, respectively, observing statistically significant differences between low and moderate level (P = 0.004) and low and high level (P < 0.001). A strong association (chi2 = 9.771; P = 0.002) was observed among a high physical activity level and a normal concentration of Lp(a) (less than 30 mg/dL). A lifestyle characterized by high physical activity is associated with normal Lp(a) levels.

Long-term habitual physical activity is associated with lower distractibility in a Stroop interference task in aging: Behavioral and ERP evidence.

PubMed

Gajewski, Patrick D; Falkenstein, Michael

2015-08-01

Aging is associated with compromised executive control functions. Several lines of evidence point to beneficial effects of physical activity on cognition which indicate that regular physical activity may counteract the age-related decline of some executive functions. Here, we investigate the effects of lifelong physical activity (about 50 years) on interference processing in two matched groups of 20 physically high active and 20 low active healthy older men using event-related potentials (ERPs). In a low interference block of the Stroop task, participants had to indicate the meaning of color-words, while color was either compatible or incompatible with the meaning. In the high interference block, participants were asked to respond according to the ink color of the word and to ignore its meaning. Physically active seniors showed faster reaction times, lower individual variability in reaction times, and higher accuracy compared to low active seniors, particularly in the high interference block. This result was confirmed in the classic paper-and-pencil version of the Stroop task showing higher interference score in the low active than high active individuals. ERPs revealed a shorter latency of the P2 and generally more negative amplitudes of the fronto-central N2 and N450 components in the high active group compared to the low active group. The amount of interference was negatively correlated with objectively measured fitness and self-reported physical activity. The positive effect of physical fitness on interference processing in the behavioral data was related to N2 and N450 amplitudes. Taken together, this suggests that seniors reporting long-term physical activity may exhibit generally enhanced activity in the frontal cortex which enables more efficient interference resolution in the Stroop task. Copyright © 2015 Elsevier Inc. All rights reserved.

Associations of physical fitness and academic performance among schoolchildren.

PubMed

Van Dusen, Duncan P; Kelder, Steven H; Kohl, Harold W; Ranjit, Nalini; Perry, Cheryl L

2011-12-01

Public schools provide opportunities for physical activity and fitness surveillance, but are evaluated and funded based on students' academic performance, not their physical fitness. Empirical research evaluating the connections between fitness and academic performance is needed to justify curriculum allocations to physical activity programs. Analyses were based on a convenience sample of 254,743 individually matched standardized academic (TAKS™) and fitness (FITNESSGRAM(®) ) test records of students, grades 3-11, collected by 13 Texas school districts. We categorized fitness results in quintiles by age and gender and used mixed effects regression models to compare the academic performance of the top and bottom fitness groups for each test. All fitness variables except body mass index (BMI) showed significant, positive associations with academic performance after adjustment for socio-demographic covariates, with standardized mean difference effect sizes ranging from .07 to .34. Cardiovascular fitness showed the largest interquintile difference in TAKS score (32-75 points), followed by curl-ups. Additional adjustment for BMI and curl-ups showed dose-response associations between cardiovascular fitness and academic scores (p < .001 for both genders and outcomes). Analysis of BMI demonstrated limited, nonlinear association with academic performance after socio-demographic and fitness adjustments. Fitness was strongly and significantly related to academic performance. Cardiovascular fitness showed a dose-response association with academic performance independent of other socio-demographic and fitness variables. The association appears to peak in late middle to early high school. We recommend that policymakers consider physical education (PE) mandates in middle high school, school administrators consider increasing PE time, and PE practitioners emphasize cardiovascular fitness. © 2011, American School Health Association.

Evaluation of Deep Learning Models for Predicting CO2 Flux

NASA Astrophysics Data System (ADS)

Halem, M.; Nguyen, P.; Frankel, D.

2017-12-01

Artificial neural networks have been employed to calculate surface flux measurements from station data because they are able to fit highly nonlinear relations between input and output variables without knowing the detail relationships between the variables. However, the accuracy in performing neural net estimates of CO2 flux from observations of CO2 and other atmospheric variables is influenced by the architecture of the neural model, the availability, and complexity of interactions between physical variables such as wind, temperature, and indirect variables like latent heat, and sensible heat, etc. We evaluate two deep learning models, feed forward and recurrent neural network models to learn how they each respond to the physical measurements, time dependency of the measurements of CO2 concentration, humidity, pressure, temperature, wind speed etc. for predicting the CO2 flux. In this paper, we focus on a) building neural network models for estimating CO2 flux based on DOE data from tower Atmospheric Radiation Measurement data; b) evaluating the impact of choosing the surface variables and model hyper-parameters on the accuracy and predictions of surface flux; c) assessing the applicability of the neural network models on estimate CO2 flux by using OCO-2 satellite data; d) studying the efficiency of using GPU-acceleration for neural network performance using IBM Power AI deep learning software and packages on IBM Minsky system.

Predictors for Physical Activity in Adolescent Girls Using Statistical Shrinkage Techniques for Hierarchical Longitudinal Mixed Effects Models

PubMed Central

Grant, Edward M.; Young, Deborah Rohm; Wu, Tong Tong

2015-01-01

We examined associations among longitudinal, multilevel variables and girls’ physical activity to determine the important predictors for physical activity change at different adolescent ages. The Trial of Activity for Adolescent Girls 2 study (Maryland) contributed participants from 8th (2009) to 11th grade (2011) (n=561). Questionnaires were used to obtain demographic, and psychosocial information (individual- and social-level variables); height, weight, and triceps skinfold to assess body composition; interviews and surveys for school-level data; and self-report for neighborhood-level variables. Moderate to vigorous physical activity minutes were assessed from accelerometers. A doubly regularized linear mixed effects model was used for the longitudinal multilevel data to identify the most important covariates for physical activity. Three fixed effects at the individual level and one random effect at the school level were chosen from an initial total of 66 variables, consisting of 47 fixed effects and 19 random effects variables, in additional to the time effect. Self-management strategies, perceived barriers, and social support from friends were the three selected fixed effects, and whether intramural or interscholastic programs were offered in middle school was the selected random effect. Psychosocial factors and friend support, plus a school’s physical activity environment, affect adolescent girl’s moderate to vigorous physical activity longitudinally. PMID:25928064

Predictability of the California Current System

NASA Technical Reports Server (NTRS)

Miller, Arthur J.; Chereskin, T.; Cornuelle, B. D.; Niiler, P. P.; Moisan, J. R.; Lindstrom, Eric (Technical Monitor)

2001-01-01

The physical and biological oceanography of the Southern California Bight (SCB), a highly productive subregion of the California Current System (CCS) that extends from Point Conception, California, south to Ensenada, Mexico, continues to be extensively studied. For example, the California Cooperative Oceanic Fisheries Investigations (CalCOFI) program has sampled this region for over 50 years, providing an unparalleled time series of physical and biological data. However, our understanding of what physical processes control the large-scale and mesoscale variations in these properties is incomplete. In particular, the non-synoptic and relatively coarse spatial sampling (70km) of the hydrographic grid does not completely resolve the mesoscale eddy field (Figure 1a). Moreover, these unresolved physical variations exert a dominant influence on the evolution of the ecosystem. In recent years, additional datasets that partially sample the SCB have become available. Acoustic Doppler Current Profiler (ADCP) measurements, which now sample upper-ocean velocity between stations, and sea level observations along TOPEX tracks give a more complete picture of the mesoscale variability. However, both TOPEX and ADCP are well-sampled only along the cruise or orbit tracks and coarsely sampled in time and between tracks. Surface Lagrangian drifters also sample the region, although irregularly in time and space. SeaWiFS provides estimates of upper-ocean chlorophyll-a (chl-alpha), usually giving nearly complete coverage for week-long intervals, depending on cloud coverage. Historical ocean color data from the Coastal Zone Color Scanner (CZCS) has been used extensively to determine phytoplankton patterns and variability, characterize the primary production across the SCB coastal fronts, and describe the seasonal and interannual variability in pigment concentrations. As in CalCOFI, these studies described much of the observed structures and their variability over relatively large space and time scales.

Large and local-scale influences on physical and chemical characteristics of coastal waters of Western Europe during winter

NASA Astrophysics Data System (ADS)

Tréguer, Paul; Goberville, Eric; Barrier, Nicolas; L'Helguen, Stéphane; Morin, Pascal; Bozec, Yann; Rimmelin-Maury, Peggy; Czamanski, Marie; Grossteffan, Emilie; Cariou, Thierry; Répécaud, Michel; Quéméner, Loic

2014-11-01

There is now a strong scientific consensus that coastal marine systems of Western Europe are highly sensitive to the combined effects of natural climate variability and anthropogenic climate change. However, it still remains challenging to assess the spatial and temporal scales at which climate influence operates. While large-scale hydro-climatic indices, such as the North Atlantic Oscillation (NAO) or the East Atlantic Pattern (EAP) and the weather regimes such as the Atlantic Ridge (AR), are known to be relevant predictors of physical processes, changes in coastal waters can also be related to local hydro-meteorological and geochemical forcing. Here, we study the temporal variability of physical and chemical characteristics of coastal waters located at about 48°N over the period 1998-2013 using (1) sea surface temperature, (2) sea surface salinity and (3) nutrient concentration observations for two coastal sites located at the outlet of the Bay of Brest and off Roscoff, (4) river discharges of the major tributaries close to these two sites and (5) regional and local precipitation data over the region of interest. Focusing on the winter months, we characterize the physical and chemical variability of these coastal waters and document changes in both precipitation and river runoffs. Our study reveals that variability in coastal waters is connected to the large-scale North Atlantic atmospheric circulation but is also partly explained by local river influences. Indeed, while the NAO is strongly related to changes in sea surface temperature at the Brest and Roscoff sites, the EAP and the AR have a major influence on precipitations, which in turn modulate river discharges that impact sea surface salinity at the scale of the two coastal stations.

Change in physical education motivation and physical activity behavior during middle school.

PubMed

Cox, Anne E; Smith, Alan L; Williams, Lavon

2008-11-01

To test a mediational model of the relationships among motivation-related variables in middle-school physical education and leisure-time physical activity behavior. Sixth- and seventh-grade physical education students from five middle schools in the midwest United States completed a survey containing measures of study variables on two occasions, 1 year apart. Motivation-related constructs positively predicted leisure-time physical activity behavior. Enjoyment of activities in physical education and physical activity during class mediated the relationship between self-determined motivation in physical education and leisure-time physical activity. Perceived competence, autonomy, and relatedness were important antecedent variables in the model, with autonomy and relatedness showing less stability over time and positively predicting self-determined motivation. Students' leisure-time physical activity is linked to motivation-related experiences in physical education. Perceptions of competence, autonomy, and relatedness, self-determined motivation, enjoyment, and physical activity in the physical education setting directly or indirectly predict leisure-time physical activity. The associations suggest that more adaptive motivation corresponds to transfer of behavior across contexts. Also, the findings suggest that the efficacy of school-based physical activity interventions, within and outside of school, is linked to the degree of support for students' self-determined motivation.

Does sexual selection explain human sex differences in aggression?

PubMed

Archer, John

2009-08-01

I argue that the magnitude and nature of sex differences in aggression, their development, causation, and variability, can be better explained by sexual selection than by the alternative biosocial version of social role theory. Thus, sex differences in physical aggression increase with the degree of risk, occur early in life, peak in young adulthood, and are likely to be mediated by greater male impulsiveness, and greater female fear of physical danger. Male variability in physical aggression is consistent with an alternative life history perspective, and context-dependent variability with responses to reproductive competition, although some variability follows the internal and external influences of social roles. Other sex differences, in variance in reproductive output, threat displays, size and strength, maturation rates, and mortality and conception rates, all indicate that male aggression is part of a sexually selected adaptive complex. Physical aggression between partners can be explained using different evolutionary principles, arising from the conflicts of interest between males and females entering a reproductive alliance, combined with variability following differences in societal gender roles. In this case, social roles are particularly important since they enable both the relatively equality in physical aggression between partners from Western nations, and the considerable cross-national variability, to be explained.

Climatic and Catchment-Scale Predictors of Chinese Stream Insect Richness Differ between Taxonomic Groups

PubMed Central

Tonkin, Jonathan D.; Shah, Deep Narayan; Kuemmerlen, Mathias; Li, Fengqing; Cai, Qinghua; Haase, Peter; Jähnig, Sonja C.

2015-01-01

Little work has been done on large-scale patterns of stream insect richness in China. We explored the influence of climatic and catchment-scale factors on stream insect (Ephemeroptera, Plecoptera, Trichoptera; EPT) richness across mid-latitude China. We assessed the predictive ability of climatic, catchment land cover and physical structure variables on genus richness of EPT, both individually and combined, in 80 mid-latitude Chinese streams, spanning a 3899-m altitudinal gradient. We performed analyses using boosted regression trees and explored the nature of their influence on richness patterns. The relative importance of climate, land cover, and physical factors on stream insect richness varied considerably between the three orders, and while important for Ephemeroptera and Plecoptera, latitude did not improve model fit for any of the groups. EPT richness was linked with areas comprising high forest cover, elevation and slope, large catchments and low temperatures. Ephemeroptera favoured areas with high forest cover, medium-to-large catchment sizes, high temperature seasonality, and low potential evapotranspiration. Plecoptera richness was linked with low temperature seasonality and annual mean, and high slope, elevation and warm-season rainfall. Finally, Trichoptera favoured high elevation areas, with high forest cover, and low mean annual temperature, seasonality and aridity. Our findings highlight the variable role that catchment land cover, physical properties and climatic influences have on stream insect richness. This is one of the first studies of its kind in Chinese streams, thus we set the scene for more in-depth assessments of stream insect richness across broader spatial scales in China, but stress the importance of improving data availability and consistency through time. PMID:25909190

Health-related quality of life in patients with hepatocellular carcinoma: the mediation effects of illness perceptions and coping.

PubMed

Fan, Sheng-Yu; Eiser, Christine; Ho, Ming-Chih; Lin, Cheng-Yao

2013-06-01

The aims of this study were to explore health-related quality of life (HRQOL) in patients with hepatocellular carcinoma (HCC). We report the following: (1) differences in HRQOL between patients with HCC and the general population; (2) significant physical and psychological predictors of HRQOL; and (3) mediation effects of illness perceptions and coping on HRQOL. Patients with HCC (n = 286) from Taiwan completed standardized measures of HRQOL, illness perception (cognitive representations, emotional representations and illness comprehensibility) and coping (emotion-oriented and problem-orientation coping). Demographic and physical variables were also collected. Patients with HCC had worse global HRQOL, physical, role, cognitive and social functioning, but better emotional functioning than the general population. Physical variables and cognitive representation were significant predictors of global HRQOL, physical functioning and emotional functioning. Cognitive representation mediated the relationships between physical variables and global HRQOL, physical functioning and emotional functioning, but coping only mediated the relationship between cognitive representation and global HRQOL. The results suggest that physical variables have direct effects on global HRQOL and physical functioning, but there were also partial mediations through cognitive representation. The effect of physical variables on emotional functioning was mediated through cognitive and emotional representations. Patients with better performance status and positive illness perceptions tended to report better HRQOL, but those with negative illness perceptions and who used more emotion-oriented coping had worse HRQOL. Limitations of the work associated with use of theory and measures developed in Europe and the US are discussed, as are the clinical implications for patients with HCC. Copyright © 2012 John Wiley & Sons, Ltd.

Gamma rays from blazars

NASA Astrophysics Data System (ADS)

Tavecchio, Fabrizio

2017-01-01

Blazars are high-energy engines providing us natural laboratories to study particle acceleration, relativistic plasma processes, magnetic field dynamics, black hole physics. Key informations are provided by observations at high-energy (in particular by Fermi/LAT) and very-high energy (by Cherenkov telescopes). I give a short account of the current status of the field, with particular emphasis on the theoretical challenges connected to the observed ultra-fast variability events and to the emission of flat spectrum radio quasars in the very high energy band.

Physical activity levels of community-dwelling older adults are influenced by winter weather variables.

PubMed

Jones, G R; Brandon, C; Gill, D P

2017-07-01

Winter weather conditions may negatively influence participation of older adults in daily physical activity (PA). Assess the influence of winter meteorological variables, day-time peak ambient temperature, windchill, humidity, and snow accumulation on the ground to accelerometer measured PA values in older adults. 50 community-dwelling older adults (77.4±4.7yrs; range 71-89; 12 females) living in Southwestern Ontario (Latitude 42.9°N Longitude 81.2° W) Canada, wore a waist-borne accelerometer during active waking hours (12h) for 7 consecutive days between February and April 2007. Hourly temperature, windchill, humidity, and snowfall accumulation were obtained from meteorological records and time locked to hourly accelerometer PA values. Regression analysis revealed significant relationships between time of day, ambient daytime high temperature and a humidity for participation in PA. Windchill temperature added no additional influence over PA acclamation already influenced by ambient day-time temperature and the observed variability in PA patterns relative to snow accumulation over the study period was too great to warrant its inclusion in the model. Most PA was completed in the morning hours and increased as the winter month's transitioned to spring (February through April). An equation was developed to adjust for winter weather conditions using temperature, humidity and time of day. Accurate PA assessment during the winter months must account for the ambient daytime high temperatures, humidity, and time of day. These older adults were more physically active during the morning hours and became more active as the winter season transitioned to spring. Copyright © 2017 Elsevier B.V. All rights reserved.

Landscape-scale soil moisture heterogeneity and its influence on surface fluxes at the Jornada LTER site: Evaluating a new model parameterization for subgrid-scale soil moisture variability

NASA Astrophysics Data System (ADS)

Baker, I. T.; Prihodko, L.; Vivoni, E. R.; Denning, A. S.

2017-12-01

Arid and semiarid regions represent a large fraction of global land, with attendant importance of surface energy and trace gas flux to global totals. These regions are characterized by strong seasonality, especially in precipitation, that defines the level of ecosystem stress. Individual plants have been observed to respond non-linearly to increasing soil moisture stress, where plant function is generally maintained as soils dry down to a threshold at which rapid closure of stomates occurs. Incorporating this nonlinear mechanism into landscape-scale models can result in unrealistic binary "on-off" behavior that is especially problematic in arid landscapes. Subsequently, models have `relaxed' their simulation of soil moisture stress on evapotranspiration (ET). Unfortunately, these relaxations are not physically based, but are imposed upon model physics as a means to force a more realistic response. Previously, we have introduced a new method to represent soil moisture regulation of ET, whereby the landscape is partitioned into `BINS' of soil moisture wetness, each associated with a fractional area of the landscape or grid cell. A physically- and observationally-based nonlinear soil moisture stress function is applied, but when convolved with the relative area distribution represented by wetness BINS the system has the emergent property of `smoothing' the landscape-scale response without the need for non-physical impositions on model physics. In this research we confront BINS simulations of Bowen ratio, soil moisture variability and trace gas flux with soil moisture and eddy covariance observations taken at the Jornada LTER dryland site in southern New Mexico. We calculate the mean annual wetting cycle and associated variability about the mean state and evaluate model performance against this variability and time series of land surface fluxes from the highly instrumented Tromble Weir watershed. The BINS simulations capture the relatively rapid reaction to wetting events and more prolonged response to drying cycles, as opposed to binary behavior in the control.

Novel models on fluid's variable thermo-physical properties for extensive study on convection heat and mass transfer

NASA Astrophysics Data System (ADS)

Shang, De-Yi; Zhong, Liang-Cai

2017-01-01

Our novel models for fluid's variable physical properties are improved and reported systematically in this work for enhancement of theoretical and practical value on study of convection heat and mass transfer. It consists of three models, namely (1) temperature parameter model, (2) polynomial model, and (3) weighted-sum model, respectively for treatment of temperature-dependent physical properties of gases, temperature-dependent physical properties of liquids, and concentration- and temperature-dependent physical properties of vapour-gas mixture. Two related components are proposed, and involved in each model for fluid's variable physical properties. They are basic physic property equations and theoretical similarity equations on physical property factors. The former, as the foundation of the latter, is based on the typical experimental data and physical analysis. The latter is built up by similarity analysis and mathematical derivation based on the former basic physical properties equations. These models are available for smooth simulation and treatment of fluid's variable physical properties for assurance of theoretical and practical value of study on convection of heat and mass transfer. Especially, so far, there has been lack of available study on heat and mass transfer of film condensation convection of vapour-gas mixture, and the wrong heat transfer results existed in widespread studies on the related research topics, due to ignorance of proper consideration of the concentration- and temperature-dependent physical properties of vapour-gas mixture. For resolving such difficult issues, the present novel physical property models have their special advantages.

Co-occurring mental illness and health care utilization and expenditures in adults with obesity and chronic physical illness.

PubMed

Shen, Chan; Sambamoorthi, Usha; Rust, George

2008-06-01

The objectives of the study were to compare health care expenditures between adults with and without mental illness among individuals with obesity and chronic physical illness. We performed a cross-sectional analysis of 2440 adults (older than age 21) with obesity using a nationally representative survey of households, the Medical Expenditure Panel Survey. Chronic physical illness consisted of self-reported asthma, diabetes, heart disease, hypertension, or osteoarthritis. Mental illness included affective disorders; anxiety, somatoform, dissociative, personality disorders; and schizophrenia. Utilization and expenditures by type of service (total, inpatient, outpatient, emergency room, pharmacy, and other) were the dependent variables. Chi-square tests, logistic regression on likelihood of use, and ordinary least squares regression on logged expenditures among users were performed. All regressions controlled for gender, race/ethnicity, age, martial status, region, education, employment, poverty status, health insurance, smoking, and exercise. All analyses accounted for the complex design of the survey. We found that 25% of adults with obesity and physical illness had a mental illness. The average total expenditures for obese adults with physical illness and mental illness were $9897; average expenditures were $6584 for those with physical illness only. Mean pharmacy expenditures for obese adults with physical illness and mental illness and for those with physical illness only were $3343 and $1756, respectively. After controlling for all independent variables, among adults with obesity and physical illness, those with mental illness were more likely to use emergency services and had higher total, outpatient, and pharmaceutical expenditures than those without mental illness. Among individuals with obesity and chronic physical illness, expenditures increased when mental illness is added. Our study findings suggest cost-savings efforts should examine the reasons for high utilization and expenditures for those with obesity, chronic physical illness, and mental illness.

Teamwork in the Music Room

ERIC Educational Resources Information Center

Criss, Ellen

2010-01-01

Physical education teachers and coaches of athletic teams are well aware of the values of strong team spirit, and they depend on cohesion among team members to successfully achieve their goals. "High-performing teams... do not necessarily have the best individual talent and ability available, which means that other variables--such as motivation,…

Rising synchrony controls western North American ecosystems

Treesearch

Bryan A. Black; Peter van der Sleen; Emanuele Di Lorenzo; Daniel Griffin; William J. Sydeman; Jason B. Dunham; Ryan R. Rykaczewski; Marisol García-Reyes; Mohammad Safeeq; Ivan Arismendi; Steven J. Bograd

2018-01-01

Along the western margin of North America, the winter expression of the North Pacific High (NPH) strongly influences interannual variability in coastal upwelling, storm track position, precipitation, and river discharge. Coherence among these factors induces covariance among physical and biological processes across adjacent marine and terrestrial ecosystems. Here, we...

Small size transformer provides high power regulation with low ripple and maximum control

NASA Technical Reports Server (NTRS)

Manoli, R.; Ulrich, B. R.

1971-01-01

Single, variable, transformer/choke device does work of several. Technique reduces drawer assembly physical size and design and manufacturing cost. Device provides power, voltage current and impedance regulation while maintaining maximum control of linearity and ensuring extremely low ripple. Nulling is controlled to very fine degree.

Influence of Biochar on Nitrogen Fractions in a Coastal Plain Soil

USDA-ARS?s Scientific Manuscript database

Interest in use of biochar from pyrolysis of biomass to sequester C and improve soil productivity has increased; however, research has shown biochar has a high variability in physical and chemical characteristics. Greater understanding is needed about the effects of biochar on soil N dynamics in ag...

Robust signals of future projections of Indian summer monsoon rainfall by IPCC AR5 climate models: Role of seasonal cycle and interannual variability

NASA Astrophysics Data System (ADS)

Jayasankar, C. B.; Surendran, Sajani; Rajendran, Kavirajan

2015-05-01

Coupled Model Intercomparison Project phase 5 (Fifth Assessment Report of Intergovernmental Panel on Climate Change) coupled global climate model Representative Concentration Pathway 8.5 simulations are analyzed to derive robust signals of projected changes in Indian summer monsoon rainfall (ISMR) and its variability. Models project clear future temperature increase but diverse changes in ISMR with substantial intermodel spread. Objective measures of interannual variability (IAV) yields nearly equal chance for future increase or decrease. This leads to discrepancy in quantifying changes in ISMR and variability. However, based primarily on the physical association between mean changes in ISMR and its IAV, and objective methods such as k-means clustering with Dunn's validity index, mean seasonal cycle, and reliability ensemble averaging, projections fall into distinct groups. Physically consistent groups of models with the highest reliability project future reduction in the frequency of light rainfall but increase in high to extreme rainfall and thereby future increase in ISMR by 0.74 ± 0.36 mm d-1, along with increased future IAV. These robust estimates of future changes are important for useful impact assessments.

The Relations of Cognitive, Behavioral, and Physical Activity Variables to Depression Severity in Traumatic Brain Injury: Reanalysis of Data From a Randomized Controlled Trial.

PubMed

Bombardier, Charles H; Fann, Jesse R; Ludman, Evette J; Vannoy, Steven D; Dyer, Joshua R; Barber, Jason K; Temkin, Nancy R

To explore the relations of cognitive, behavioral, and physical activity variables to depression severity among people with traumatic brain injury (TBI) undergoing a depression treatment trial. Community. Adults (N = 88) who sustained complicated mild to severe TBI within the past 10 years, met criteria for major depressive disorder, and completed study measures. Randomized controlled trial. Participants were randomized to cognitive-behavioral therapy (n = 58) or usual care (n = 42). Outcomes were measured at baseline and 16 weeks. We combined the groups and used regressions to explore the relations among theoretical variables and depression outcomes. Depression severity was measured with the Hamilton Depression Rating Scale and Symptom Checklist-20. Theory-based measures were the Dysfunctional Attitudes Scale (DAS), Automatic Thoughts Questionnaire (ATQ), Environmental Rewards Observation Scale (EROS), and the International Physical Activity Questionnaire (IPAQ). Compared with non-TBI norms, baseline DAS and ATQ scores were high and EROS and IPAQ scores were low. All outcomes improved from baseline to 16 weeks except the DAS. The ATQ was an independent predictor of baseline depression. An increase in EROS scores was correlated with decreased depression. Increasing participation in meaningful roles and pleasant activities may be a promising approach to treating depression after TBI.

Effects of urban development on stream ecosystems alongthe Front Range of the Rocky Mountains, Colorado and Wyoming

USGS Publications Warehouse

Sprague, Lori A.; Zuellig, Robert E.; Dupree, Jean A.

2006-01-01

The U.S. Geological Survey (USGS) conducted a study from 2002 through 2003 through its National Water-Quality Assessment (NAWQA) Program to determine the effects of urbanization on the physical, chemical, and biological characteristics of stream ecosystems along the Front Range of the Rocky Mountains. The objectives of the study were to (1) examine physical, chemical, and biological responses at sites ranging from minimally to highly developed; (2) determine the major physical, chemical, and landscape variables affecting aquatic communities at these sites; and (3) evaluate the relevance of the results to the management of water resources in the South Platte River Basin.

Physical inactivity, gender and culture in Arab countries: a systematic assessment of the literature.

PubMed

Sharara, Eman; Akik, Chaza; Ghattas, Hala; Makhlouf Obermeyer, Carla

2018-05-18

Physical inactivity is associated with excess weight and adverse health outcomes. We synthesize the evidence on physical inactivity and its social determinants in Arab countries, with special attention to gender and cultural context. We searched MEDLINE, Popline, and SSCI for articles published between 2000 and 2016, assessing the prevalence of physical inactivity and its social determinants. We also included national survey reports on physical activity, and searched for analyses of the social context of physical activity. We found 172 articles meeting inclusion criteria. Standardized data are available from surveys by the World Health Organization for almost all countries, but journal articles show great variability in definitions, measurements and methodology. Prevalence of inactivity among adults and children/adolescents is high across countries, and is higher among women. Some determinants of physical inactivity in the region (age, gender, low education) are shared with other regions, but specific aspects of the cultural context of the region seem particularly discouraging of physical activity. We draw on social science studies to gain insights into why this is so. Physical inactivity among Arab adults and children/adolescents is high. Studies using harmonized approaches, rigorous analytic techniques and a deeper examination of context are needed to design appropriate interventions.

Physical activity level and its sociodemographic correlates in a peri-urban Nepalese population: a cross-sectional study from the Jhaukhel-Duwakot health demographic surveillance site

PubMed Central

2014-01-01

Background Physical inactivity is a leading risk factor for cardiovascular and other noncommunicable diseases in high-, low- and middle-income countries. Nepal, a low-income country in South Asia, is undergoing an epidemiological transition. Although the reported national prevalence of physical inactivity is relatively low, studies in urban and peri-urban localities have always shown higher prevalence. Therefore, this study aimed to measure physical activity in three domains—work, travel and leisure—in a peri-urban community and assess its variations across different sociodemographic correlates. Methods Adult participants (n = 640) from six randomly selected wards of the Jhaukhel-Duwakot Health Demographic Surveillance Site (JD-HDSS) near Kathmandu responded to the Global Physical Activity Questionnaire. To determine total physical activity, we calculated the metabolic equivalent of task in minutes/week for each domain and combined the results. Respondents were categorized into high, moderate or low physical activity. We also calculated the odds ratio for low physical activity in various sociodemographic variables and self-reported cardiometabolic states. Results The urbanizing JD-HDSS community showed a high prevalence of low physical activity (43.3%; 95% CI 39.4–47.1). Work-related activity contributed most to total physical activity. Furthermore, women and housewives and older, more educated and self-or government-employed respondents showed a greater prevalence of physical inactivity. Respondents with hypertension, diabetes or overweight/obesity reported less physical activity than individuals without those conditions. Only 5% of respondents identified physical inactivity as a cardiovascular risk factor. Conclusions Our findings reveal a high burden of physical inactivity in a peri-urban community of Nepal. Improving the level of physical activity involves sensitizing people to its importance through appropriate multi-sector strategies that provide encouragement across all sociodemographic groups. PMID:24628997

[Changes in physical activity are not reflected in physical fitness of older teenagers. A 2-year follow-up study].

PubMed

Andersen, L B

1996-04-08

The study describes changes over two years in different physical fitness measures and the relationship between these changes and changes in physical activity. Maximal aerobic work capacity (watt(max)), functional strength, muscle endurance, agility and flexibility were measured in 259 randomly selected high school boys and girls 16.5 years of age and followed-up two years later, while they still attended school. Most physical fitness measures increased over time in boys, and in girls an increase was found in arm extensor strength and trunk extensor endurance, but watt(max) per kg body mass decreased. Changes in physical performance between 16 and 18 years of age seem to be very similar in different countries, despite differences in physical activity patterns and absolute level of performance. No change was found in time spent participating in physical activity or sports activity in either gender, but fewer girls participated in leisure-time sports at the second test (p < 0.001). Change in physical activity or sports activity did not relate to change in physical fitness level. The relationships between level of sports participation (competition, for health or none) and physical fitness measures at baseline and at the second test were weak or non-significant. Three explanations for the weak relationship between physical activity and fitness are suggested: a) part of the variability in fitness is explained by genetics, b) growth and hormonal changes, especially in boys, override the stimulus of training, and c) the physical fitness level in adolescents is so high that only physical activity at high relative intensity is supposed to have an effect on the fitness level.

Quantification of physical activity using the QAPACE questionnaire: A two stage cluster sample design survey of children and adolescents attending urban school.

PubMed

Barbosa, N; Sanchez, C E; Patiño, E; Lozano, B; Thalabard, J; Le Bozec, S; Rieu, M

2015-07-01

Quantification of physical activity as energy expenditure is important since youth for the prevention of chronic non communicable diseases in adulthood. It is necessary to quantify physical activity expressed in daily energy expenditure (DEE) in school children and adolescents between 8-16 years, by age, gender and socioeconomic level (SEL) in Bogotá. This is a Two Stage Cluster Survey Sample. From a universe of 4700 schools and 760000 students from three existing socioeconomic levels in Bogotá (low, medium and high). The random sample was 20 schools and 1840 students (904 boys and 936 girls). Foreshadowing desertion of participants and inconsistency in the questionnaire responses, the sample size was increased. Thus, six individuals of each gender for each of the nine age groups were selected, resulting in a total sample of 2160 individuals. Selected students filled the QAPACE questionnaire under supervision. The data was analyzed comparing means with multivariate general linear model. Fixed factors used were: gender (boys and girls), age (8 to 16 years old) and tri-strata SEL (low, medium and high); as independent variables were assessed: height, weight, leisure time, expressed in hours/day and dependent variable: daily energy expenditure DEE (kJ.kg-1.day-1): during leisure time (DEE-LT), during school time (DEE-ST), during vacation time (DEE-VT), and total mean DEE per year (DEEm-TY) RESULTS: Differences in DEE by gender, in boys, LT and all DEE, with the SEL all variables were significant; but age-SEL was only significant in DEE-VT. In girls, with the SEL all variables were significant. The Post-hoc multiple comparisons tests were significant with age using Fisher's Least Significant Difference (LSD) test in all variables. For both genders and for all SELs the values in girls had the higher value except SEL high (5-6) The boys have higher values in DEE-LT, DEE-ST, DEE-VT; except in DEEm-TY in SEL (5-6) In SEL (5-6) all DEEs for both genders are highest. For SEL (3-4) all DEEs are lowest. Children and adolescents in Bogotá have less DEE than at other latitudes. Girls have more free time but lower energy expenditure in their different activities. The socioeconomic level has influence in DEE.

Quantification of physical activity using the QAPACE Questionnaire: a two stage cluster sample design survey of children and adolescents attending urban school.

PubMed

Barbosa, Nicolas; Sanchez, Carlos E; Patino, Efrain; Lozano, Benigno; Thalabard, Jean C; LE Bozec, Serge; Rieu, Michel

2016-05-01

Quantification of physical activity as energy expenditure is important since youth for the prevention of chronic non communicable diseases in adulthood. It is necessary to quantify physical activity expressed in daily energy expenditure (DEE) in school children and adolescents between 8-16 years, by age, gender and socioeconomic level (SEL) in Bogotá. This is a Two Stage Cluster Survey Sample. From a universe of 4700 schools and 760000 students from three existing socioeconomic levels in Bogotá (low, medium and high). The random sample was 20 schools and 1840 students (904 boys and 936 girls). Foreshadowing desertion of participants and inconsistency in the questionnaire responses, the sample size was increased. Thus, 6 individuals of each gender for each of the nine age groups were selected, resulting in a total sample of 2160 individuals. Selected students filled the QAPACE questionnaire under supervision. The data was analyzed comparing means with multivariate general linear model. Fixed factors used were: gender (boys and girls), age (8 to 16 years old) and tri-strata SEL (low, medium and high); as independent variables were assessed: height, weight, leisure time, expressed in hours/day and dependent variable: daily energy expenditure DEE (kJ.kg-1.day-1): during leisure time (DEE-LT), during school time (DEE-ST), during vacation time (DEE-VT), and total mean DEE per year (DEEm-TY) RESULTS: Differences in DEE by gender, in boys, LT and all DEE, with the SEL all variables were significant; but age-SEL was only significant in DEE-VT. In girls, with the SEL all variables were significant. The post hoc multiple comparisons tests were significant with age using Fisher's Least Significant Difference (LSD) test in all variables. For both genders and for all SELs the values in girls had the higher value except SEL high (5-6) The boys have higher values in DEE-LT, DEE-ST, DEE-VT; except in DEEm-TY in SEL (5-6) In SEL (5-6) all DEEs for both genders are highest. For SEL (3-4) all DEEs are lowest. Children and adolescents in Bogotá have less DEE than at other latitudes. Girls have more free time but lower energy expenditure in their different activities. The socioeconomic level has influence in DEE.

Health, lifestyle, belief and knowledge differences between two ethnic groups with specific reference to tobacco, diet and physical activity.

PubMed

Anthony, Denis; Baggott, Rob; Tanner, Judith; Jones, Kathryn; Evans, Hala; Perkins, Gill; Palmer, Hilary

2012-11-01

  To compare physical activity levels, body mass index, habitual diet, tobacco use and prevalence of non-communicable disease between the two ethnic groups and to identify predictors for differences between groups.   Tobacco use, poor diet and physical inactivity are major lifestyle risk factors for chronic cardiovascular diseases, certain cancers, diabetes and chronic lung diseases. There are higher risk and incidence of these diseases in some ethnic groups, for example Asians have higher incidence of diabetes.   Cross sectional survey.   Cross sectional survey of Asians of Indian descent and white British adults conducted between October-December 2009. Main outcome variables were lifestyle behaviours and BMI. Self-reported disease diagnosis was also collected. In a regression analysis, predictors of outcome variables were demographic variables and beliefs/attitudes/knowledge towards lifestyle behaviours.   Body mass index, tobacco use and non-communicable disease (except diabetes) were lower in Indians. Indians reported lower physical activity levels and greater salt use than Whites. Tobacco use was higher in Whites, but knowledge, attitudes and beliefs were similar between Whites and Indians.   Health risk behaviour and morbidity are different between the two ethnic groups. Gender, age, educational level, beliefs, attitudes and knowledge do not explain these differences. Health promotion that aims to improve knowledge will probably not work and innovative methods are needed to improve health in high risk groups. © 2012 Blackwell Publishing Ltd.

Maternal factors predicting cognitive and behavioral characteristics of children with fetal alcohol spectrum disorders.

PubMed

May, Philip A; Tabachnick, Barbara G; Gossage, J Phillip; Kalberg, Wendy O; Marais, Anna-Susan; Robinson, Luther K; Manning, Melanie A; Blankenship, Jason; Buckley, David; Hoyme, H Eugene; Adnams, Colleen M

2013-06-01

To provide an analysis of multiple predictors of cognitive and behavioral traits for children with fetal alcohol spectrum disorders (FASDs). Multivariate correlation techniques were used with maternal and child data from epidemiologic studies in a community in South Africa. Data on 561 first-grade children with fetal alcohol syndrome (FAS), partial FAS (PFAS), and not FASD and their mothers were analyzed by grouping 19 maternal variables into categories (physical, demographic, childbearing, and drinking) and used in structural equation models (SEMs) to assess correlates of child intelligence (verbal and nonverbal) and behavior. A first SEM using only 7 maternal alcohol use variables to predict cognitive/behavioral traits was statistically significant (B = 3.10, p < .05) but explained only 17.3% of the variance. The second model incorporated multiple maternal variables and was statistically significant explaining 55.3% of the variance. Significantly correlated with low intelligence and problem behavior were demographic (B = 3.83, p < .05) (low maternal education, low socioeconomic status [SES], and rural residence) and maternal physical characteristics (B = 2.70, p < .05) (short stature, small head circumference, and low weight). Childbearing history and alcohol use composites were not statistically significant in the final complex model and were overpowered by SES and maternal physical traits. Although other analytic techniques have amply demonstrated the negative effects of maternal drinking on intelligence and behavior, this highly controlled analysis of multiple maternal influences reveals that maternal demographics and physical traits make a significant enabling or disabling contribution to child functioning in FASD.

Goals and intentions mediate efficacy beliefs and declining physical activity in high school girls.

PubMed

Dishman, Rod K; Saunders, Ruth P; Felton, Gwen; Ward, Dianne S; Dowda, Marsha; Pate, Russ R

2006-12-01

According to theory, girls who set goals about increasing their physical activity and who are dissatisfied with their current activity level are likely to form intentions to be active and to carry out those intentions, especially if they have high efficacy and control beliefs about being physically active. We tested those ideas while observing naturally occurring change during high school. A cohort of 431 black and white girls was tested at the end of their 9th- and 12th-grade academic years. Confirmatory factor analysis established the structural invariance of the measures across the 3-year study period. Structural equation modeling and panel analysis were used to determine whether changes in goal setting and satisfaction would mediate relations of self-efficacy and perceived behavioral control with changes in intention and physical activity. Testing occurred between February and May in 1999 and 2004. Data were analyzed in 2006. Goal setting and intention mediated the indirect relation between self-efficacy and change in physical activity. Perceived behavioral control and physical activity change were related directly and also indirectly by a path mediated through satisfaction and intention. Black girls had lower self-efficacy, but changes in other variables were unrelated to race. These observations of longitudinal relations elaborate application of self-efficacy theory and the theory of planned behavior to physical activity by showing that goal setting and satisfaction mediate the relations of self-efficacy and perceived behavioral control with changes in intention and physical activity. The results encourage additional research to identify the sources and development of physical activity goals, and their attainment, among girls, and whether experimental manipulation of goals and intentions can mitigate the decline in girls' physical activity during high school.

Time-Integral Correlations of Multiple Variables With the Relativistic-Electron Flux at Geosynchronous Orbit: The Strong Roles of Substorm-Injected Electrons and the Ion Plasma Sheet

NASA Astrophysics Data System (ADS)

Borovsky, Joseph E.

2017-12-01

Time-integral correlations are examined between the geosynchronous relativistic electron flux index Fe1.2 and 31 variables of the solar wind and magnetosphere. An "evolutionary algorithm" is used to maximize correlations. Time integrations (into the past) of the variables are found to be superior to time-lagged variables for maximizing correlations with the radiation belt. Physical arguments are given as to why. Dominant correlations are found for the substorm-injected electron flux at geosynchronous orbit and for the pressure of the ion plasma sheet. Different sets of variables are constructed and correlated with Fe1.2: some sets maximize the correlations, and some sets are based on purely solar wind variables. Examining known physical mechanisms that act on the radiation belt, sets of correlations are constructed (1) using magnetospheric variables that control those physical mechanisms and (2) using the solar wind variables that control those magnetospheric variables. Fe1.2-increasing intervals are correlated separately from Fe1.2-decreasing intervals, and the introduction of autoregression into the time-integral correlations is explored. A great impediment to discerning physical cause and effect from the correlations is the fact that all solar wind variables are intercorrelated and carry much of the same information about the time sequence of the solar wind that drives the time sequence of the magnetosphere.

The aging neuromuscular system and motor performance

PubMed Central

Keenan, Kevin G.

2016-01-01

Age-related changes in the basic functional unit of the neuromuscular system, the motor unit, and its neural inputs have a profound effect on motor function, especially among the expanding number of old (older than ∼60 yr) and very old (older than ∼80 yr) adults. This review presents evidence that age-related changes in motor unit morphology and properties lead to impaired motor performance that includes 1) reduced maximal strength and power, slower contractile velocity, and increased fatigability; and 2) increased variability during and between motor tasks, including decreased force steadiness and increased variability of contraction velocity and torque over repeat contractions. The age-related increase in variability of motor performance with aging appears to involve reduced and more variable synaptic inputs that drive motor neuron activation, fewer and larger motor units, less stable neuromuscular junctions, lower and more variable motor unit action potential discharge rates, and smaller and slower skeletal muscle fibers that coexpress different myosin heavy chain isoforms in the muscle of older adults. Physical activity may modify motor unit properties and function in old men and women, although the effects on variability of motor performance are largely unknown. Many studies are of cross-sectional design, so there is a tremendous opportunity to perform high-impact and longitudinal studies along the continuum of aging that determine 1) the influence and cause of the increased variability with aging on functional performance tasks, and 2) whether lifestyle factors such as physical exercise can minimize this age-related variability in motor performance in the rapidly expanding numbers of very old adults. PMID:27516536

Perceived influence and college students' diet and physical activity behaviors: an examination of ego-centric social networks.

PubMed

Harmon, Brook E; Forthofer, Melinda; Bantum, Erin O; Nigg, Claudio R

2016-06-06

Obesity is partially a social phenomenon, with college students particularly vulnerable to changes in social networks and obesity-related behaviors. Currently, little is known about the structure of social networks among college students and their potential influence on diet and physical activity behaviors. The purpose of the study was to examine social influences impacting college students' diet and physical activity behaviors, including sources of influence, comparisons between sources' and students' behaviors, and associations with meeting diet and physical activity recommendations. Data was collected from 40 students attending college in Hawaii. Participants completed diet and physical activity questionnaires and a name generator. Participants rated nominees' influence on their diet and physical activity behaviors as well as compared nominees' behaviors to their own. Descriptive statistics were used to look at perceptions of influence across network groups. Logistic regression models were used to examine associations between network variables and odds of meeting recommendations. A total of 325 nominations were made and included: family (n = 116), college friends (n = 104), high school friends (n = 87), and significant others (n = 18). Nearly half of participants were not from Hawaii. Significant others of non-Hawaii students were perceived to be the most influential (M(SD) = 9(1.07)) and high school friends the least influential (M(SD) = 1.31(.42)) network. Overall, perceived influence was highest for diet compared to physical activity, but varied based on comparisons with nominees' behaviors. Significant others were most often perceived has having similar (44 %) or worse (39 %) eating behaviors than participants, and those with similar eating behaviors were perceived as most influential (M(SD) = 9.25(1.04)). Few associations were seen between network variables and odds of meeting recommendations. Among the groups nominated, high school friends were perceived as least influential, especially among students who moved a long distance for college. Intervention strategies addressing perceived norms and using peer leaders may help promote physical activity among college students, while diet interventions may need to involve significant others in order to be successful. Testing of these types of intervention strategies and continued examination of social networks and their influences on diet and physical activity behaviors are needed.

Awareness and correlates of the role of physical activity in breast cancer prevention among Japanese women: results from an internet-based cross-sectional survey.

PubMed

Miyawaki, Rina; Shibata, Ai; Ishii, Kaori; Oka, Koichiro

2014-07-07

Although considerable evidence has demonstrated that physical activity is associated with breast cancer prevention, few studies have assessed the level of awareness of this association. Awareness is a key first step to successful of behavior change. Increasing awareness may contribute to promote physical activity and prevent breast cancer at the population level. The present study examined the prevalence and correlates of awareness about the role of physical activity in breast cancer prevention among Japanese women. 1,000 Japanese women aged 20-69 years (mean age: 44.3 ± 13.4 years) who responded to an internet-based cross-sectional survey. Awareness of the role of physical activity in breast cancer prevention, knowledge of breast cancer (symptom, risk factor, screening), exposure to information about physical activity and cancer, a self-reported physical activity, and sociodemographic variables (age, marital status, having a child, education level, employment status, and household income) were obtained. Force-entry logistic regression analysis was used. The prevalence of awareness was 31.5% (95% CI: 28.6-34.4). Factors significantly associated with awareness included sociodemographic variables, exposure to information, and knowledge of breast cancer. Being married (AOR, 95% CI: 1.75, 1.05-2.92) was positively related to awareness, while having children (0.65, 0.36-0.86) was negatively related. College graduates or those with higher levels of education (1.50, 1.01-2.22) were significantly more likely to be aware than those who had not graduated high school. Moreover, exposure to information (2.11, 1.51-2.95), and high knowledge of symptoms (2.43, 1.75-3.36) were positively associated with awareness. Finally, low knowledge of risk factors (0.30, 0.22-0.40) was negatively associated with awareness. Japanese women through internet-based study were poorly aware of the role of physical activity in breast cancer prevention. Awareness was especially low among individuals with children and higher knowledge of risk factors whereas high in married women, those with higher educational level, exposure to information, and greater knowledge of symptoms. The findings suggest that strategies to increase the awareness about the preventive role of physical activity are needed for breast cancer prevention in consideration of subgroups with low awareness.

Association between physiological falls risk and physical performance tests among community-dwelling older adults

PubMed Central

Singh, Devinder KA; Pillai, Sharmila GK; Tan, Sin Thien; Tai, Chu Chiau; Shahar, Suzana

2015-01-01

Background Physical performance and balance declines with aging and may lead to increased risk of falls. Physical performance tests may be useful for initial fall-risk screening test among community-dwelling older adults. Physiological profile assessment (PPA), a composite falls risk assessment tool is reported to have 75% accuracy to screen for physiological falls risk. PPA correlates with Timed Up and Go (TUG) test. However, the association between many other commonly used physical performance tests and PPA is not known. The aim of the present study was to examine the association between physiological falls risk measured using PPA and a battery of physical performance tests. Methods One hundred and forty older adults from a senior citizens club in Kuala Lumpur, Malaysia (94 females, 46 males), aged 60 years and above (65.77±4.61), participated in this cross-sectional study. Participants were screened for falls risk using PPA. A battery of physical performance tests that include ten-step test (TST), short physical performance battery (SPPB), functional reach test (FRT), static balance test (SBT), TUG, dominant hand-grip strength (DHGS), and gait speed test (GST) were also performed. Spearman’s rank correlation and binomial logistic regression were performed to examine the significantly associated independent variables (physical performance tests) with falls risk (dependent variable). Results Approximately 13% older adults were at high risk of falls categorized using PPA. Significant differences (P<0.05) were demonstrated for age, TST, SPPB, FRT, SBT, TUG between high and low falls risk group. A significant (P<0.01) weak correlation was found between PPA and TST (r=0.25), TUG (r=0.27), SBT (r=0.23), SPPB (r=−0.33), and FRT (r=−0.23). Binary logistic regression results demonstrated that SBT measuring postural sways objectively using a balance board was the only significant predictor of physiological falls risk (P<0.05, odds ratio of 2.12). Conclusion The reference values of physical performance tests in our study may be used as a guide for initial falls screening to categorize high and low physiological falls risk among community-dwelling older adults. A more comprehensive assessment of falls risk can be performed thereafter for more specific intervention of underlying impairments. PMID:26316727

Do heart failure status and psychosocial variables moderate the relationship between leisure time physical activity and mortality risk among patients with a history of myocardial infarction?

PubMed

Oosterom-Calo, Rony; Te Velde, Saskia J; Stut, Wim; Drory, Yaacov; Brug, Johannes; Gerber, Yariv

2016-10-12

Leisure time physical activity (LTPA) is inversely related to mortality risk among patients with a history of myocardial infarction (MI). The aims were to explore if heart failure (HF) status and psychosocial variables moderate the association. Participants (n = 1169) were from a multi-center prospective cohort study. Information on LTPA (none, irregular,1-150, 151-300 and >300 weekly minutes), depression, social support and other prognostic indicators were collected 10-13 years after index MI. Cox regressions were conducted, adjusting for potential confounders. In case of significant moderation by HF-status or psychosocial variables, stratified analyses were performed. During follow-up (M = 8.4 years), 25.6 % of the sample had died. LTPA was inversely associated with mortality (p for trend < 0.01 in all models). HF did not, but psychosocial variables did, moderate the association. In the LTPA category 1-150 weekly minutes, patients with a high level of depression had a lower mortality risk in comparison to those with a low level (hazard ratios (95 % confidence intervals) were 0.43 (0.25, 0.75) versus 0.69 (0.36, 1.32)), and patients with a low level of social support had a lower mortality risk in comparison to those with a high level (0.40 (0.21, 0.77) versus 0.71 (0.39, 1.27)). In the category >300 min, patients with a high level of social support had a lower mortality risk than those with a low level (0.38 (0.19, 0.79) versus 0.51 (0.30, 0.87)). LTPA was inversely related to mortality risk of post-MI patients. HF did not moderate the relationship; depression and social support partially did.

Applying an economical scale-aware PDF-based turbulence closure model in NOAA NCEP GCMs

NASA Astrophysics Data System (ADS)

Belochitski, A.; Krueger, S. K.; Moorthi, S.; Bogenschutz, P.; Pincus, R.

2016-12-01

A novel unified representation of sub-grid scale (SGS) turbulence, cloudiness, and shallow convection is being implemented into the NOAA NCEP Global Forecasting System (GFS) general circulation model. The approach, known as Simplified High Order Closure (SHOC), is based on predicting a joint PDF of SGS thermodynamic variables and vertical velocity and using it to diagnose turbulent diffusion coefficients, SGS fluxes, condensation and cloudiness. Unlike other similar methods, only one new prognostic variable, turbulent kinetic energy (TKE), needs to be intoduced, making the technique computationally efficient.SHOC is now incorporated into a version of GFS, as well as into the next generation of the NCEP global model - NOAA Environmental Modeling System (NEMS). Turbulent diffusion coefficients computed by SHOC are now used in place of those produced by the boundary layer turbulence and shallow convection parameterizations. Large scale microphysics scheme is no longer used to calculate cloud fraction or the large-scale condensation/deposition. Instead, SHOC provides these variables. Radiative transfer parameterization uses cloudiness computed by SHOC.Outstanding problems include high level tropical cloud fraction being too high in SHOC runs, possibly related to the interaction of SHOC with condensate detrained from deep convection.Future work will consist of evaluating model performance and tuning the physics if necessary, by performing medium-range NWP forecasts with prescribed initial conditions, and AMIP-type climate tests with prescribed SSTs. Depending on the results, the model will be tuned or parameterizations modified. Next, SHOC will be implemented in the NCEP CFS, and tuned and evaluated for climate applications - seasonal prediction and long coupled climate runs. Impact of new physics on ENSO, MJO, ISO, monsoon variability, etc will be examined.

Bio-optical and physical variability in the subarctic North Atlantic Ocean during the spring of 1989

NASA Technical Reports Server (NTRS)

Dickey, T.; Marra, J.; Stramska, M.; Langdon, C.; Granata, T.; Plueddemann, A.; Weller, R.; Yoder, J.

1994-01-01

A unique set of physical, bio-optical, and meteorological observations were made from a mooring located in the open ocean south of Iceland (59 deg 29.5 min N, 20 deg 49.8 min W) from April 13 to June 12 1989. The present measurements are apparently the first to resolve the rapid transition to springtime physical and biological conditions at such a high latitude site. Our data were collected with bio-optical and physical moored systems every few minutes. The abrupt onset of springtime stratification was observed with the mixed layer shoaling from approximately 550 m to approximately 50 m in approximately 5 days. During this period a major phytoplankton bloom occurred with a tenfold increase in near-surface chlorophyll concentration in less than 3 weeks. Our statistical analysis indicates that the velocity shear in the upper layer is driven primarily by local wind stress. Mesoscale variability is also apparent from these and concurrent airborne oceangraphic lidar observations. Our complementary modeling results suggest that the near-surface layer may be reasonably well described by a one-dimensional model and that the spring bloom was initiated during incipient near-surface restratification.

Maternal prenatal smoking, parental antisocial behavior, and early childhood physical aggression.

PubMed

Huijbregts, Stephan C J; Séguin, Jean R; Zoccolillo, Mark; Boivin, Michel; Tremblay, Richard E

2008-01-01

This study investigated joint effects of maternal prenatal smoking and parental history of antisocial behavior on physical aggression between ages 17 and 42 months in a population sample of children born in Québec (N = 1,745). An analysis of variance (ANOVA) showed significant main effects of maternal prenatal smoking and a significant interaction between maternal prenatal smoking and mother's history of antisocial behavior in the prediction of children's probability to display high and rising physical aggression. The interaction indicated that the effects of heavy smoking during pregnancy (> or =10 cigarettes/day) were greater when the mother also had a serious history of antisocial behavior. The effects remained significant after the introduction of control variables (e.g., hostile-reactive parenting, family functioning, parental separation/divorce, family income, and maternal education). Another significant interaction not accounted for by control variables was observed for maternal prenatal smoking and family income, indicating more serious effects of maternal prenatal smoking under relatively low-income, conditions. Both interactions indicate critical adversities that, in combination with maternal prenatal smoking, have supra-additive effects on (the development of) physical aggression during early childhood. These findings may have implications for the selection of intervention targets and strategies.

Psychological and biographical differences between secondary school teachers experiencing high and low levels of burnout.

PubMed

Pierce, C M; Molloy, G N

1990-02-01

A total of 750 teachers from 16 government and non-government schools from areas of contrasted socio-economic status (SES) responded to a questionnaire designed to investigate associations between selected aspects of burnout among teachers working in secondary schools in Victoria, Australia. By comparing high and low burnout groups on biographic, psychological and work pattern variables, differences between teachers experiencing high and low levels of burnout were identified. Multiple regression analyses assessed the relative importance of these variables in accounting for the variance in each of the three burnout subscales. School type was related to perceptions of stress and burnout. Higher levels of burnout were associated with poorer physical health, higher rates of absenteeism, lower self-confidence and more frequent use of regressive coping strategies. Teachers classified as experiencing high levels of burnout attributed most of the stress in their lives to teaching and reported low levels of career commitment and satisfaction. Further, teachers who recorded high levels of burnout were characterised by lower levels of the personality disposition of hardiness, lower levels of social support, higher levels of role stress and more custodial pupil control ideologies than their low-burnout counterparts. Psychological variables were found to be more significant predictors of burnout than biographical variables.

Environmental factors and beta2-adrenergic receptor polymorphism: influence on the energy expenditure and nutritional status of obese women.

PubMed

Rosado, Eliane Lopes; Bressan, Josefina; Martínez, J Alfredo

2015-05-01

Our aim was to evaluate the influence of the Gln27Glu polymorphism of the β2-adrenergic receptor (ADRβ2) gene, fat intake and physical activity on the energy expenditure (EE) and nutritional status of obese women. Sixty obese women (30-46 years) participated in the study and were assigned to three groups depending on the genotypes: Gln27Gln, Gln27Glu and Glu27Glu. At baseline and after nutritional intervention, the anthropometric and body composition (bioelectrical impedance), dietary, EE (indirect calorimetry) and biochemical variables were measured. All women received a high-fat test meal to determine the postprandial EE (short-term) and an energy-restricted diet for 10 weeks (long term). The frequencies of Gln27Gln, Gln27Glu and Glu27Glu were 36.67, 40.0 and 23.33 %, respectively. Anthropometric and biochemical variables and EE did not differ between groups, although women who had no polymorphism demonstrated decreased carbohydrate oxidation. On the other hand, the Glu27Glu genotype showed a positive relation with EE in physical activity and fat oxidation. The environmental factors and Gln27Glu polymorphism did not influence the nutritional status and EE of obese women, but physical activity in obese women with the polymorphism in the ADRβ2 gene can promote fat oxidation. The results suggest that encouraging the practice of physical exercise is important considering the high frequency of this polymorphism in obese subjects.

Prediction of early summer rainfall over South China by a physical-empirical model

NASA Astrophysics Data System (ADS)

Yim, So-Young; Wang, Bin; Xing, Wen

2014-10-01

In early summer (May-June, MJ) the strongest rainfall belt of the northern hemisphere occurs over the East Asian (EA) subtropical front. During this period the South China (SC) rainfall reaches its annual peak and represents the maximum rainfall variability over EA. Hence we establish an SC rainfall index, which is the MJ mean precipitation averaged over 72 stations over SC (south of 28°N and east of 110°E) and represents superbly the leading empirical orthogonal function mode of MJ precipitation variability over EA. In order to predict SC rainfall, we established a physical-empirical model. Analysis of 34-year observations (1979-2012) reveals three physically consequential predictors. A plentiful SC rainfall is preceded in the previous winter by (a) a dipole sea surface temperature (SST) tendency in the Indo-Pacific warm pool, (b) a tripolar SST tendency in North Atlantic Ocean, and (c) a warming tendency in northern Asia. These precursors foreshadow enhanced Philippine Sea subtropical High and Okhotsk High in early summer, which are controlling factors for enhanced subtropical frontal rainfall. The physical empirical model built on these predictors achieves a cross-validated forecast correlation skill of 0.75 for 1979-2012. Surprisingly, this skill is substantially higher than four-dynamical models' ensemble prediction for 1979-2010 period (0.15). The results here suggest that the low prediction skill of current dynamical models is largely due to models' deficiency and the dynamical prediction has large room to improve.

Gender Inequality in the Couple Relationship and Leisure-Based Physical Exercise

PubMed Central

Annandale, Ellen; Hammarström, Anne

2015-01-01

Aims To analyse whether gender inequality in the couple relationship was related to leisure-based physical activity, after controlling for earlier physical activity and confounders. Methods Data drawn from the Northern Swedish Cohort of all pupils in their final year of compulsory schooling in a town in the North of Sweden. The sample consisted of 772 respondents (n = 381 men, n = 391 women) in the 26-year follow-up (in 2007, aged 42) who were either married or cohabiting. Ordinal regression, for men and women separately, was used to assess the association between gender inequality (measured as self-perceived equality in the couple relationship using dummy variables) and a measure of exercise frequency, controlling for prior exercise frequency, socioeconomic status, the presence of children in the home, and longer than usual hours in paid work. Results The perception of greater gender equality in the couple relationship was associated with higher levels of physical activity for both men and women. This remained significant when the other variables were controlled for. Amongst men the confidence intervals were high. Conclusions The results point to the potential of perceived gender equality in the couple relationship to counteract the general time poverty and household burden that often arises from the combination of paid work and responsibility for children and the home, especially for women. The high confidence intervals among men indicate the need for more research within the field with larger samples. PMID:26196280

High school students' representations and understandings of electric fields

NASA Astrophysics Data System (ADS)

Cao, Ying; Brizuela, Bárbara M.

2016-12-01

This study investigates the representations and understandings of electric fields expressed by Chinese high school students 15 to 16 years old who have not received high school level physics instruction. The physics education research literature has reported students' conceptions of electric fields postinstruction as indicated by students' performance on textbook-style questions. It has, however, inadequately captured student ideas expressed in other situations yet informative to educational research. In this study, we explore students' ideas of electric fields preinstruction as shown by students' representations produced in open-ended activities. 92 participant students completed a worksheet that involved drawing comic strips about electric charges as characters of a cartoon series. Three students who had spontaneously produced arrow diagrams were interviewed individually after class. We identified nine ideas related to electric fields that these three students spontaneously leveraged in the comic strip activity. In this paper, we describe in detail each idea and its situated context. As most research in the literature has understood students as having relatively fixed conceptions and mostly identified divergences in those conceptions from canonical targets, this study shows students' reasoning to be more variable in particular moments, and that variability includes common sense resources that can be productive for learning about electric fields.

Gender and racial differences for suicide attempters and ideators in a high-risk community corrections population.

PubMed

McCullumsmith, Cheryl B; Clark, C Brendan; Perkins, Adam; Fife, Jessaka; Cropsey, Karen L

2013-01-01

Community corrections populations are a high-risk group who carry multiple suicide risk factors. To identify factors correlated with historical suicide attempts and ideation among African-American men, African-American women, White men, and White women in a community corrections population. Self-report data from 18,753 enrollees in community corrections were analyzed. Multinomial logistic regression analyses were conducted to determine associations between historical suicidal ideation and attempts among the four demographic groups. Participants with historical suicide attempts tended to be younger, White, female, be taking psychotropic medication, have a history of physical or sexual abuse, and meet criteria for dependence on alcohol, amphetamines, cocaine, opioids, or sedatives. Five variables were commonly associated with suicide attempts for all four race/gender groups: younger age, being on disability or retirement, taking psychotropic medication, history of sexual or physical abuse, and cocaine dependence. Other demographic variables had race or gender specificities as risk factors for suicide attempts. Participants had high rates of historical suicide attempts with unique correlates differentiating attempters from ideators among different racial and gender groups. Cocaine dependence was universal predictor of suicide attempts, while other substance dependencies show specific racial and gender profiles associated with suicide attempts.

Follow-Up Care for Older Women With Breast Cancer

DTIC Science & Technology

1999-08-01

range of patient outcomes, including primary tumor therapy and mortality, self -reported upper body function, and overall physical function. Methods...mor therapy, all cause mortality, self -reported function and overall physical function than upper body function, and overall physical was the interview...Major Analytic Variables mor therapy and all cause mortality, as well as self -reported upper body and overall physical Dependent Variables. Our first

Mediating Effects of Self-Efficacy, Benefits and Barriers on the Association between Peer and Parental Factors and Physical Activity among Adolescent Girls with a Lower Educational Level.

PubMed

Verloigne, Maite; Cardon, Greet; De Craemer, Marieke; D'Haese, Sara; De Bourdeaudhuij, Ilse

2016-01-01

The prevalence of physical activity among lower educated adolescent girls is low, suggesting it is important to have insights into the complex processes that may underlie their physical activity levels. Therefore, this study aimed to examine the mediating effects of self-efficacy, perceived benefits and barriers on the associations between peer and parental variables and physical activity among lower educated adolescent girls. In total, 226 girls (mean age 16.0±1.0 years; 53% technical education; 47% vocational education) from a convenience sample of 6 secondary schools in Flanders, Belgium, completed a questionnaire on their total physical activity level and related peer and parental variables (i.e. modeling of physical activity, co-participation in physical activities and encouragement to be active) and personal variables (i.e. self-efficacy to be active, and specific perceived benefits of physical activity and specific barriers to be active). Mediating effects were tested using MacKinnon's product-of-coefficients test based on multilevel linear regression analyses. Higher peer and parental modeling, co-participation and encouragement were significantly related to a higher physical activity level among adolescent girls (p<0.05). Self-efficacy, the perceived benefits of having fun, being around friends or meeting new people, and not being bored and the perceived barrier of not liking physical activity mediated several associations between peer and parental variables and girls' physical activity, with some of the mediated proportions exceeding 60%. This study contributed to a better understanding of the complexity of how parental and peer factors work together with personal factors to influence the physical activity levels of adolescent girls with a lower educational level. Interventions should involve both peers and parents, as they may influence girls' physical activity both directly and indirectly through the internalisation of several personal variables, such as self-efficacy to be active and the perceived benefit of having fun.

Squeezing of Particle Distributions by Expanding Magnetic Turbulence and Space Weather Variability

NASA Astrophysics Data System (ADS)

Ruffolo, D. J.; Tooprakai, P.; Seripienlert, A.; Chuychai, P.; Matthaeus, W. H.

2014-12-01

Among the space weather effects due to gradual solar storms, greatly enhanced high-energy ion fluxes can cause radiation damage to satellites, spacecraft, and astronauts, which motivates examination of the transport of high-energy solar ions to Earth orbit. Ions of low kinetic energy (up to ˜2sim 2 MeV/nucleon) from impulsive solar events exhibit abrupt changes due to filamentation of magnetic connection from the Sun, indicating that anisotropic, field-aligned magnetic flux tube-like structures persist to Earth orbit. By employing a corresponding spherical two-component model of Alfv'enic (slab) and 2D magnetic fluctuations to trace simulated trajectories in the solar wind, we show that the distribution of high-energy (E≥1Egeq1 GeV) protons from gradual solar events is squeezed toward magnetic flux structures with a specific polarity due to the conical shape of the flux structures, which results from the expanding flow of the solar wind. It is difficult to observationally determine what polarity of flux structure the Earth is in at a given time, so this transport phenomenon contributes to event-to-event variability in ground level enhancements of GeV-range ions from solar storms, presenting a fundamental uncertainty in space weather prediction. Partially supported by the Thailand Research Fund, a Postdoctoral Fellowship from the Thailand Center of Excellence in Physics, a Research Fellowship from the Faculty of Science, Mahidol University, the U.S. NSF (AGS-1063439 and SHINE AGS-1156094), NASA (Heliophysics Theory NNX08AI47G & NNX11AJ44G), and the Solar Probe Plus/ISIS project. KEYWORDS: [7807] SPACE PLASMA PHYSICS / Charged particle motion and acceleration, [7863] SPACE PLASMA PHYSICS / Turbulence, [2118] INTERPLANETARY PHYSICS / Energetic particles, solar, [7984] SPACE WEATHER / Space radiation environment

Total energy expenditure in adults with cerebral palsy as assessed by doubly labeled water.

PubMed

Johnson, R K; Hildreth, H G; Contompasis, S H; Goran, M I

1997-09-01

To characterize total energy expenditure (TEE) in free-living adults with cerebral palsy (CP) using the doubly labeled water technique, and to determine those physiologic variables and characteristics of CP that were markers of TEE in adults with CP. TEE was measured using the doubly labeled water technique in 30 free-living adults with CP (12 women, 18 men). To determine the best markers of TEE, the following factors were examined: CP status, resting metabolic rate (RMR), anthropometric characteristics and body composition by means of dual-energy x-ray absorptiometry (DXA) and skinfold thickness measurements, energy cost of leisure-time activities, and oral-motor impairment. Means +/- standard deviations, t tests, Pearson product-moment correlation coefficients, Spearman rank correlation coefficients, chi 2, stepwise multiple-correlation regression analysis, and analysis of covariance were used to examine the relationships among variables of interest. TEE was highly variable in the sample (mean = 2,455 +/- 622 kcal/day for men and 1,986 +/- 363 kcal/day for women). Stepwise regression analysis showed that TEE was best predicted in the sample by RMR, percentage body fat determined by DXA, ambulation status, and sex (multiple R = .68, P = .003). When practical, easily measured variables were used, TEE was best predicted by height, ambulation status, percentage body fat by skinfold thickness measurements, and sex (multiple R = .61, P. = 018). The contribution of energy expended in physical activity to TEE was significantly higher in the ambulatory subjects than the nonambulatory subjects (25% vs 16%, respectively; P = .009). The high degree of variability in TEE, largely attributable to high interindividual variation in energy expended in physical activity, makes it difficult to provide general guidelines for energy requirements for adults with CP. Because ambulation status was an important predictor of TEE, it must be accounted for in estimating energy requirements in this population.

Optimized design on condensing tubes high-speed TIG welding technology magnetic control based on genetic algorithm

NASA Astrophysics Data System (ADS)

Lu, Lin; Chang, Yunlong; Li, Yingmin; Lu, Ming

2013-05-01

An orthogonal experiment was conducted by the means of multivariate nonlinear regression equation to adjust the influence of external transverse magnetic field and Ar flow rate on welding quality in the process of welding condenser pipe by high-speed argon tungsten-arc welding (TIG for short). The magnetic induction and flow rate of Ar gas were used as optimum variables, and tensile strength of weld was set to objective function on the base of genetic algorithm theory, and then an optimal design was conducted. According to the request of physical production, the optimum variables were restrained. The genetic algorithm in the MATLAB was used for computing. A comparison between optimum results and experiment parameters was made. The results showed that the optimum technologic parameters could be chosen by the means of genetic algorithm with the conditions of excessive optimum variables in the process of high-speed welding. And optimum technologic parameters of welding coincided with experiment results.

Temporal dynamics of estuarine phytoplankton: A case study of San Francisco Bay

USGS Publications Warehouse

Cloern, J.E.; Cole, B.E.; Wong, R.L.J.; Alpine, A.E.

1985-01-01

Detailed surveys throughout San Francisco Bay over an annual cycle (1980) show that seasonal variations of phytoplankton biomass, community composition, and productivity can differ markedly among estuarine habitat types. For example, in the river-dominated northern reach (Suisun Bay) phytoplankton seasonality is characterized by a prolonged summer bloom of netplanktonic diatoms that results from the accumulation of suspended particulates at the convergence of nontidal currents (i.e. where residence time is long). Here turbidity is persistently high such that phytoplankton growth and productivity are severely limited by light availability, the phytoplankton population turns over slowly, and biological processes appear to be less important mechanisms of temporal change than physical processes associated with freshwater inflow and turbulent mixing. The South Bay, in contrast, is a lagoon-type estuary less directly coupled to the influence of river discharge. Residence time is long (months) in this estuary, turbidity is lower and estimated rates of population growth are high (up to 1-2 doublings d-1), but the rapid production of phytoplankton biomass is presumably balanced by grazing losses to benthic herbivores. Exceptions occur for brief intervals (days to weeks) during spring when the water column stratifies so that algae retained in the surface layer are uncoupled from benthic grazing, and phytoplankton blooms develop. The degree of stratification varies over the neap-spring tidal cycle, so the South Bay represents an estuary where (1) biological processes (growth, grazing) and a physical process (vertical mixing) interact to cause temporal variability of phytoplankton biomass, and (2) temporal variability is highly dynamic because of the short-term variability of tides. Other mechanisms of temporal variability in estuarine phytoplankton include: zooplankton grazing, exchanges of microalgae between the sediment and water column, and horizontal dispersion which transports phytoplankton from regions of high productivity (shallows) to regions of low productivity (deep channels). Multi-year records of phytoplankton biomass show that large deviations from the typical annual cycles observed in 1980 can occur, and that interannual variability is driven by variability of annual precipitation and river discharge. Here, too, the nature of this variability differs among estuary types. Blooms occur only in the northern reach when river discharge falls within a narrow range, and the summer biomass increase was absent during years of extreme drought (1977) or years of exceptionally high discharge (1982). In South Bay, however, there is a direct relationship between phytoplankton biomass and river discharge. As discharge increases so does the buoyancy input required for density stratification, and wet years are characterized by persistent and intense spring blooms. ?? 1985 Dr W. Junk Publishers.

Low Sleeping Time, High TV Viewing Time, and Physical Inactivity in School Are Risk Factors for Obesity in Pre-Adolescent Thai Children.

PubMed

Thasanasuwan, Wiyada; Srichan, Weerachat; Kijboonchoo, Kallaya; Yamborisut, Uruwan; Wimonpeerapattana, Wanphen; Rojroongwasinkul, Nipa; Khouw, Ilse Tan; Deurenberg, Pual

2016-03-01

Explore the association between physically active behavior and obesity in 7- to 12-years-old Thai children. As part of SEANUTS Thailand, information on anthropometry, physical activity, and sociodemographic variables were collected in 7- to 12-years-old urban and rural Thai children. Multi-stage sampling technique was used and 1,345 children (32% urban, and 50.3% boys) participated in the study. Anthropometric measurements included weight, height, and BMI-for-age Z-scores (BAZ) using World Health Organization Growth Reference. Obesity was defined as BAZ > 2SD. Physical activity was assessed using a validated physical activity questionnaire (PAQ). The PAQ provided an activity score, activity time in school, sleeping hours, and TV watching time as categorical variable, low, moderate, and high. Chi-square by likelihood ratio test and logistic regression were used to compare obese and non-obese groups. The overall prevalence of overweight and obesity was 10.2 and 10.8% respectively, whereas 8.2% was classified as thin. Maternal education and religion did not differ between obese and non-obese children. However, obese children's family income was higher. After controlling for family income, maternal education, and religion, obese children were significantly less active during break times in school, slept less, and watched more TV than non-obese. However, there was no difference in the activity score of obese and non-obese children. The study showed that physical activity during break time in school, sleep duration, and hours of TV viewing were associated with obesity in pre-adolescent Thai children. It is important to note that activity score was not associated with obesity. One of the most important benefits to be physically active in childhood is the potential to maintain this behavior into adulthood. Therefore, programs that encourage healthy behaviors and address these modifiable risk factors should be incorporated in the school curriculum.

Dannie Heineman Prize for Mathematical Physics: Applying mathematical techniques to solve important problems in quantum theory

NASA Astrophysics Data System (ADS)

Bender, Carl

2017-01-01

The theory of complex variables is extremely useful because it helps to explain the mathematical behavior of functions of a real variable. Complex variable theory also provides insight into the nature of physical theories. For example, it provides a simple and beautiful picture of quantization and it explains the underlying reason for the divergence of perturbation theory. By using complex-variable methods one can generalize conventional Hermitian quantum theories into the complex domain. The result is a new class of parity-time-symmetric (PT-symmetric) theories whose remarkable physical properties have been studied and verified in many recent laboratory experiments.

Factors Influencing Physical Activity Behavior among Iranian Women with Type 2 Diabetes Using the Extended Theory of Reasoned Action.

PubMed

Didarloo, Alireza; Shojaeizadeh, Davoud; Ardebili, Hassan Eftekhar; Niknami, Shamsaddin; Hajizadeh, Ebrahim; Alizadeh, Mohammad

2011-10-01

Findings of most studies indicate that the only way to control diabetes and prevent its debilitating effects is through the continuous performance of self-care behaviors. Physical activity is a non-pharmacological method of diabetes treatment and because of its positive effects on diabetic patients, it is being increasingly considered by researchers and practitioners. This study aimed at determining factors influencing physical activity among diabetic women in Iran, using the extended theory of reasoned action in Iran. A sample of 352 women with type 2 diabetes, referring to a Diabetes Clinic in Khoy, Iran, participated in the study. Appropriate instruments were designed to measure the desired variables (knowledge of diabetes, personal beliefs, subjective norms, perceived self-efficacy, behavioral intention and physical activity behavior). The reliability and validity of the instruments were examined and approved. Statistical analyses of the study were conducted by inferential statistical techniques (independent t-test, correlations and regressions) using the SPSS package. The findings of this investigation indicated that among the constructs of the model, self efficacy was the strongest predictor of intentions among women with type 2 diabetes and both directly and indirectly affected physical activity. In addition to self efficacy, diabetic patients' physical activity also was influenced by other variables of the model and sociodemographic factors. Our findings suggest that the high ability of the theory of reasoned action extended by self-efficacy in forecasting and explaining physical activity can be a base for educational intervention. Educational interventions based on the proposed model are necessary for improving diabetics' physical activity behavior and controlling disease.

Associations of neighbourhood greenness with physical and mental health: do walking, social coherence and local social interaction explain the relationships?

PubMed

Sugiyama, T; Leslie, E; Giles-Corti, B; Owen, N

2008-05-01

Studies have shown associations between health indices and access to "green" environments but the underlying mechanisms of this association are not clear. To examine associations of perceived neighbourhood "greenness" with perceived physical and mental health and to investigate whether walking and social factors account for the relationships. A mailed survey collected the following data from adults (n = 1895) in Adelaide, Australia: physical and mental health scores (12-item short-form health survey); perceived neighbourhood greenness; walking for recreation and for transport; social coherence; local social interaction and sociodemographic variables. After adjusting for sociodemographic variables, those who perceived their neighbourhood as highly green had 1.37 and 1.60 times higher odds of better physical and mental health, respectively, compared with those who perceived the lowest greenness. Perceived greenness was also correlated with recreational walking and social factors. When walking for recreation and social factors were added to the regression models, recreational walking was a significant predictor of physical health; however, the association between greenness and physical health became non-significant. Recreational walking and social coherence were associated with mental health and the relationship between greenness and mental health remained significant. Perceived neighbourhood greenness was more strongly associated with mental health than it was with physical health. Recreational walking seemed to explain the link between greenness and physical health, whereas the relationship between greenness and mental health was only partly accounted for by recreational walking and social coherence. The restorative effects of natural environments may be involved in the residual association of this latter relationship.

School and Neighborhood Predictors of Physical Fitness in Elementary School Students.

PubMed

Kahan, David; McKenzie, Thomas L

2017-06-01

We assessed the associations of 5 school and 7 neighborhood variables with fifth-grade students achieving Healthy Fitness Zone (HFZ) or Needs Improvement-Health Risk (NI-HR) on aerobic capacity (AC) and body composition (BC) physical fitness components of the state-mandated FITNESSGRAM ® physical fitness test. Data for outcome (physical fitness) and predictor (school and neighborhood) variables were extracted from various databases (eg, Data Quest, Walk Score ® ) for 160 schools located in San Diego, California. Predictor variables that were at least moderately correlated (|r| ≥ .30) with ≥1 outcome variables in univariate analyses were retained for ordinary least squares regression analyses. The mean percentages of students achieving HFZ AC (65.7%) and BC (63.5%) were similar (t = 1.13, p = .26), while those for NI-HR zones were significantly different (AC = 6.0% vs BC = 18.6%; t = 12.60, p < .001). Correlations were greater in magnitude for school than neighborhood demographics and stronger for BC than AC. The school variables free/reduced-price lunch (negative) and math achievement (positive) predicted fitness scores. Among neighborhood variables, percent Hispanic predicted failure of meeting the HFZ BC criterion. Creating school and neighborhood environments conducive to promoting physical activity and improving fitness is warranted. © 2017, American School Health Association.

Spatial regression analysis on 32 years of total column ozone data

NASA Astrophysics Data System (ADS)

Knibbe, J. S.; van der A, R. J.; de Laat, A. T. J.

2014-08-01

Multiple-regression analyses have been performed on 32 years of total ozone column data that was spatially gridded with a 1 × 1.5° resolution. The total ozone data consist of the MSR (Multi Sensor Reanalysis; 1979-2008) and 2 years of assimilated SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) ozone data (2009-2010). The two-dimensionality in this data set allows us to perform the regressions locally and investigate spatial patterns of regression coefficients and their explanatory power. Seasonal dependencies of ozone on regressors are included in the analysis. A new physically oriented model is developed to parameterize stratospheric ozone. Ozone variations on nonseasonal timescales are parameterized by explanatory variables describing the solar cycle, stratospheric aerosols, the quasi-biennial oscillation (QBO), El Niño-Southern Oscillation (ENSO) and stratospheric alternative halogens which are parameterized by the effective equivalent stratospheric chlorine (EESC). For several explanatory variables, seasonally adjusted versions of these explanatory variables are constructed to account for the difference in their effect on ozone throughout the year. To account for seasonal variation in ozone, explanatory variables describing the polar vortex, geopotential height, potential vorticity and average day length are included. Results of this regression model are compared to that of a similar analysis based on a more commonly applied statistically oriented model. The physically oriented model provides spatial patterns in the regression results for each explanatory variable. The EESC has a significant depleting effect on ozone at mid- and high latitudes, the solar cycle affects ozone positively mostly in the Southern Hemisphere, stratospheric aerosols affect ozone negatively at high northern latitudes, the effect of QBO is positive and negative in the tropics and mid- to high latitudes, respectively, and ENSO affects ozone negatively between 30° N and 30° S, particularly over the Pacific. The contribution of explanatory variables describing seasonal ozone variation is generally large at mid- to high latitudes. We observe ozone increases with potential vorticity and day length and ozone decreases with geopotential height and variable ozone effects due to the polar vortex in regions to the north and south of the polar vortices. Recovery of ozone is identified globally. However, recovery rates and uncertainties strongly depend on choices that can be made in defining the explanatory variables. The application of several trend models, each with their own pros and cons, yields a large range of recovery rate estimates. Overall these results suggest that care has to be taken in determining ozone recovery rates, in particular for the Antarctic ozone hole.

Physical Aggression During Early Childhood: Trajectories and Predictors

PubMed Central

Tremblay, Richard E.; Nagin, Daniel S.; Séguin, Jean R.; Zoccolillo, Mark; Zelazo, Philip D.; Boivin, Michel; Pérusse, Daniel; Japel, Christa

2012-01-01

Objectives Physical aggression in children is a major public health problem. Not only is childhood physical aggression a precursor of the physical and mental health problems that will be visited on victims, but also aggressive children themselves are at higher risk of alcohol and drug abuse, accidents, violent crimes, depression, suicide attempts, spouse abuse, and neglectful and abusive parenting. Furthermore, violence commonly results in serious injuries to the perpetrators themselves. Although it is unusual for young children to harm seriously the targets of their physical aggression, studies of physical aggression during infancy indicate that by 17 months of age, the large majority of children are physically aggressive toward siblings, peers, and adults. This study aimed, first, to identify the trajectories of physical aggression during early childhood and, second, to identify antecedents of high levels of physical aggression early in life. Such antecedents could help to understand better the developmental origins of violence later in life and to identify targets for preventive interventions. Methods A random population sample of 572 families with a 5-month-old newborn was recruited. Assessments of physical aggression frequency were obtained from mothers at 17, 30, and 42 months after birth. Using a semiparametric, mixture model, distinct clusters of physical aggression trajectories were identified. Multivariate logit regression analysis was then used to identify which family and child characteristics, before 5 months of age, predict individuals on a high-level physical aggression trajectory from 17 to 42 months after birth. Results Three trajectories of physical aggression were identified. The first was composed of children who displayed little or no physical aggression. These individuals were estimated to account for ~28% of the sample. The largest group, estimated at ~58% of the sample, followed a rising trajectory of modest aggression. Finally, a group, estimated to comprise ~14% of the sample, followed a rising trajectory of high physical aggression. Best predictors before or at birth of the high physical aggression trajectory group, controlling for the levels of the other risk factors, were having young siblings (odds ratio [OR]: 4.00; confidence interval [CI]: 2.2–7.4), mothers with high levels of antisocial behavior before the end of high school (OR: 3.1; CI: 1.1–8.6), mothers who started having children early (OR: 3.1; CI: 1.4–6.8), families with low income (OR: 2.6; CI: 1.3–5.2), and mothers who smoked during pregnancy (OR: 2.2; CI: 1.1–4.1). Best predictors at 5 months of age were mothers’ coercive parenting behavior (OR: 2.3; CI: 1.1–4.7) and family dysfunction (OR: 2.2; CI: 1.2–4.1). The OR for a high-aggression trajectory was 10.9 for children whose mother reported both high levels of antisocial behavior and early childbearing. Conclusions Most children have initiated the use of physical aggression during infancy, and most will learn to use alternatives in the following years before they enter primary school. Humans seem to learn to regulate the use of physical aggression during the preschool years. Those who do not, seem to be at highest risk of serious violent behavior during adolescence and adulthood. Results from the present study indicate that children who are at highest risk of not learning to regulate physical aggression in early childhood have mothers with a history of antisocial behavior during their school years, mothers who start childbearing early and who smoke during pregnancy, and parents who have low income and have serious problems living together. All of these variables are relatively easy to measure during pregnancy. Preventive interventions should target families with high-risk profiles on these variables. Experiments with such programs have shown long-term impacts on child abuse and child antisocial behavior. However, these impacts were not observed in families with physical violence. The problem may be that the prevention programs that were provided did not specifically target the parents’ control over their physical aggression and their skills in teaching their infant not to be physically aggressive. Most intervention programs to prevent youth physical aggression have targeted school-age children. If children normally learn not to be physically aggressive during the preschool years, then one would expect that interventions that target infants who are at high risk of chronic physical aggression would have more of an impact than interventions 5 to 10 years later, when physical aggression has become a way of life. PMID:15231972

Evaluating Air-Quality Models: Review and Outlook.

NASA Astrophysics Data System (ADS)

Weil, J. C.; Sykes, R. I.; Venkatram, A.

1992-10-01

Over the past decade, much attention has been devoted to the evaluation of air-quality models with emphasis on model performance in predicting the high concentrations that are important in air-quality regulations. This paper stems from our belief that this practice needs to be expanded to 1) evaluate model physics and 2) deal with the large natural or stochastic variability in concentration. The variability is represented by the root-mean- square fluctuating concentration (c about the mean concentration (C) over an ensemble-a given set of meteorological, source, etc. conditions. Most air-quality models used in applications predict C, whereas observations are individual realizations drawn from an ensemble. For cC large residuals exist between predicted and observed concentrations, which confuse model evaluations.This paper addresses ways of evaluating model physics in light of the large c the focus is on elevated point-source models. Evaluation of model physics requires the separation of the mean model error-the difference between the predicted and observed C-from the natural variability. A residual analysis is shown to be an elective way of doing this. Several examples demonstrate the usefulness of residuals as well as correlation analyses and laboratory data in judging model physics.In general, c models and predictions of the probability distribution of the fluctuating concentration (c), (c, are in the developmental stage, with laboratory data playing an important role. Laboratory data from point-source plumes in a convection tank show that (c approximates a self-similar distribution along the plume center plane, a useful result in a residual analysis. At pmsent,there is one model-ARAP-that predicts C, c, and (c for point-source plumes. This model is more computationally demanding than other dispersion models (for C only) and must be demonstrated as a practical tool. However, it predicts an important quantity for applications- the uncertainty in the very high and infrequent concentrations. The uncertainty is large and is needed in evaluating operational performance and in predicting the attainment of air-quality standards.

Physical activity and neighborhood resources in high school girls.

PubMed

Pate, Russell R; Colabianchi, Natalie; Porter, Dwayne; Almeida, Maria J; Lobelo, Felipe; Dowda, Marsha

2008-05-01

Physical activity behavior is influenced by a person's physical environment, but few studies have used objective measures to study the influences of the physical environment on physical activity behavior in youth. The purpose of this study was to examine the relationship between selected neighborhood physical activity resources and physical activity levels in high school girls. Participants were students in schools that had participated in a large physical activity intervention trial. The 3-Day Physical Activity Recall was completed by 1506 12th-grade girls. Data on physical activity facilities and resources in the participating communities were collected using a variety of methods. Physical activity resources within a 0.75-mile street-network buffer around each girl's home were counted using ArcGIS, version 9.1. Mixed-model regression models were used to determine if there was a relationship between three physical activity variables and the number of physical activity resources within the 0.75-mile buffer. Data were collected in 2002-2003 and analyzed in 2006-2007. On average, 3.5 physical activity resources (e.g., schools, parks, commercial facilities) were located within the 0.75-mile street-network buffer. Thirty-six percent of the girls had no physical activity resource within the buffer. When multiple physical activity resources were considered, the number of commercial physical activity facilities was significantly associated with reported vigorous physical activity, and the number of parks was associated with total METs in white girls. Multiple physical activity resources within a 0.75-mile street-network buffer around adolescent girls' homes are associated physical activity in those girls. Several types of resources are associated with vigorous physical activity and total activity in adolescent girls. Future studies should examine the temporal and causal relationships between the physical environment, physical activity, and health outcomes related to physical activity.

[TOBACCO CONSUMPTION AMONG ADULTS IN MONTERREY: RELATION TO EXERCISE REGULARLY AND FAMILY].

PubMed

Ruiz-Juan, Francisco; Isorna-Folgar, Manuel; Ruiz-Risueño, Jorge; Vaquero-Cristóbal, Raquel

2015-08-01

determine the relationship among tobacco consumption, physical activity, sociodemographic variables and family behaviours in Mexican adults. 978 Mexican adults (483 males and 495 females) were interviewed by a random routes questionnaire. Multinomial logistic regression was used to calculate odds ratio (OR) and confidence interval (CI = 95%). men have a high risk factor of tobacco comsumption in frequency and/or amount. 18 to 45 years-old is the age range with high probability of tobacco comsumption, while the more age, the less comsumption. The tobacco consumption risk is significantly low in people who have less that a primary education. Participants who have never done physical exercise have a low possibility of tobacco consumption, while the consumption is high in the group of people who have abandoned physical activity. The family context is a risk factor of tobacco consumption in frequency. About alcohol consumption, it was found that people who drink alcohol have a high probability of smoke. tobacco consumption at high frequencies and amounts and physical activity are inversely relationship. It has been also detected a direct relationship between the frequency and the amount of tobacco and alcohol consumptions; and between the frequency and the amount of tobacco consumption and the family in the tobacco consumption. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Dating Violence among High-Risk Young Women: A Systematic Review Using Quantitative and Qualitative Methods

PubMed Central

Joly, Lauren E.; Connolly, Jennifer

2016-01-01

Our systematic review identified 21 quantitative articles and eight qualitative articles addressing dating violence among high risk young women. The groups of high-risk young women in this review include street-involved, justice-involved, pregnant or parenting, involved with Child Protective Services, and youth diagnosed with a mental health issue. Our meta-analysis of the quantitative articles indicated that 34% (CI = 0.24–0.45) of high-risk young women report that they have been victims of physical dating violence and 45% (CI = 0.31–0.61) of these young women report perpetrating physical dating violence. Significant moderator variables included questionnaire and timeframe. Meta-synthesis of the qualitative studies revealed that high-risk young women report perpetrating dating violence to gain power and respect, whereas women report becoming victims of dating violence due to increased vulnerability. PMID:26840336

Systems, methods, and software for determining spatially variable distributions of the dielectric properties of a heterogeneous material

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farrington, Stephen P.

Systems, methods, and software for measuring the spatially variable relative dielectric permittivity of materials along a linear or otherwise configured sensor element, and more specifically the spatial variability of soil moisture in one dimension as inferred from the dielectric profile of the soil matrix surrounding a linear sensor element. Various methods provided herein combine advances in the processing of time domain reflectometry data with innovations in physical sensing apparatuses. These advancements enable high temporal (and thus spatial) resolution of electrical reflectance continuously along an insulated waveguide that is permanently emplaced in contact with adjacent soils. The spatially resolved reflectance ismore » directly related to impedance changes along the waveguide that are dominated by electrical permittivity contrast due to variations in soil moisture. Various methods described herein are thus able to monitor soil moisture in profile with high spatial resolution.« less

Variability at the edge: highly accreting objects in Taurus

NASA Astrophysics Data System (ADS)

Abraham, Peter; Kospal, Agnes; Szabo, Robert

2017-04-01

In Kepler K2, Campaign 13, we will obtain 80-days-long optical light curves of seven highly accreting T Tauri stars in the benchmark Taurus star forming region. Here we propose to monitor our sample simultaneously with Kepler and Spitzer, to be able to separate variability patterns related to different physical processes. Monitoring our targets with Spitzer during the final 11 days of the K2 campaign, we will clean the light curves from non-accretion effects (rotating stellar spots, dips due to passing dust structures), and construct, for the first time, a variability curve which reflects the time-dependent accretion only. We will then study and understand how time-dependent mass accretion affects the density and temperature structure of the protoplanetary disk, which sets the initial conditions for planet formation. The proposed work cannot be done without the unparalleled precision of Kepler and Spitzer. This unique and one-time opportunity motivated our DDT proposal.

The impact of physical activity on cumulative cardiovascular disease risk factors among Malaysian adults.

PubMed

Rasiah, Rajah; Thangiah, Govindamal; Yusoff, Khalid; Manikam, Rishya; Chandrasekaran, Sankara Kumar; Mustafa, Rujhan; Bakar, Najmin Binti Abu

2015-12-16

Numerous studies have shown the importance of physical activity in reducing the morbidity and mortality rates caused by cardiovascular disease (CVD). However, most of these studies emphasise little on the cumulative effect of CVD risk factors. Hence, this study investigates the association between physical exercise and cumulative CVD risk factors among adults in three different age groups. Using a sample of 7276 respondents drawn from community centers, the REDISCOVER team gathered information on physical activity, CVD risk factors (obesity, diabetes, hypertension, hypercholesterolemia, tobacco use) and socioeconomic and demographic variables in Malaysia. Because the study required medical examination, a convenience sampling frame was preferred in which all volunteers were included in the study. Fasting blood samples and anthropometric (height, weight and more) measurements were collected by trained staffs. Socio-demographic and physical activity variables were recorded through questionnaires. A Chi-square test was performed to identify the bivariate association between the covariates (socioeconomic variables, demographic variables and physical activity) and outcome variable. The association between the main exposure, physical activity, and the outcome variable, cumulative CVD risk factors, was assessed using an ordinal logistic regression model, controlling for socioeconomic status and demographic influences in three different age groups, 35-49, 50-64 and 65 and above. The mean age of participants is 51.8 (SD = 9.4). Respondents in the age groups of 35-49 (aORmoderate = 0.12; 95 % CI: 0.02 - 0.53 ) and 65 and above (aORhigh = 0.58; 95 % CI: 0.24, 0.78) showed a statistically significant inverse relationship between physical activity and cumulative CVD risk factors. However, this relationship was not significant among respondents in the 50-64 age group suggesting the possible influence of other variables, such as stress and environment. The statistically significant results show a negative association between physical exercise and cumulative CVD risk factors. However, the lack of a significant relationship in the 50-64 age group suggests the need to include other considerations in future studies, such as stress and environment.

Spatio-temporal variation in stream water chemistry in a tropical urban watershed

Treesearch

A. Ramirez; K.G. Rosas; A.E. Lugo; O.M. Ramos-Gonzalez

2014-01-01

Urban activities and related infrastructure alter the natural patterns of stream physical and chemical conditions. According to the Urban Stream Syndrome, streams draining urban landscapes are characterized by high concentrations of nutrients and ions, and might have elevated water temperatures and variable oxygen concentrations. Here, we report temporal and spatial...

Supercritical Fuel Pyrolysis

DTIC Science & Technology

2010-05-30

supercritical fluids . These temperatures and pressures will also cause the fuel to undergo pyrolytic reactions, which have the potential of forming...With regard to physical properties, supercritical fluids have highly variable densities, no surface tension, and transport properties (i.e., mass...effects in supercritical fluids , often affecting chemical reaction pathways by facilitating the formation of certain transition states [6]. Because

A Case Study of the Cognitive and Behavioral Deficits of Temporal Lobe Damage in Herpes Simplex Encephalitis.

ERIC Educational Resources Information Center

Greer, Margaret K.; And Others

1989-01-01

This case study illustrates the highly significant language difficulties, marked memory deficits, and propensity for physical aggression following temporal lobe damage brought about by herpes encephalitis, and presents the usefulness of a new diagnostic measure in delineating such a variable cognitive pattern. (Author)

Discussion of "Simple design criterion for residual energy on embankment dam stepped spillways" by Stefan Felder and Hubert Chanson

USDA-ARS?s Scientific Manuscript database

Researchers from the University of Queensland of New South Wales provided guidance to designers regarding the hydraulic performance of embankment dam stepped spillways. Their research compares a number of high-quality physical model data sets from multiple laboratories, emphasizing the variability ...

Design of a Professional Practice Simulator for Educating and Motivating First-Year Engineering Students

ERIC Educational Resources Information Center

Chesler, Naomi C.; Arastoopour, Golnaz; D'Angelo, Cynthia M.; Bagley, Elizabeth A.; Shaffer, David Williamson

2013-01-01

Increasingly, first-year engineering curricula incorporate design projects. However, the faculty and staff effort and physical resources required for the number of students enrolled can be daunting and affect the quality of instruction. To reduce these costs, ensure a high quality educational experience, and reduce variability in student outcomes…

Middle and High School Students' Conceptions of Climate Change Mitigation and Adaptation Strategies

ERIC Educational Resources Information Center

Bofferding, Laura; Kloser, Matthew

2015-01-01

Both scientists and policy-makers emphasize the importance of education for influencing pro-environmental behavior and minimizing the effects of climate change on biological and physical systems. Education has the potential to impact students' system knowledge--their understanding of the variables that affect the climate system--and action…

Cotton NDVI response to applied N at different soil EC levels

USDA-ARS?s Scientific Manuscript database

Many fields in the southeastern Coastal Plain are highly variable in soil physical properties and are irregular in shape. These two conditions may make it difficult to determine the ‘best’ area in the field to place nitrogen (N) -rich strips for normalized difference vegetative index (NDVI) -based s...

Psychosocial Predictors of Women's Physical Health in Middle Adulthood.

ERIC Educational Resources Information Center

Thomas, Sandra P.

Although health is a key element in one's experience of middle adulthood as a time of productivity and personal fulfillment, research on psychosocial factors predictive of mid-life health is sparse, especially for women. Psychosocial variables are not only highly salient to health, but also are potentially modifiable by women themselves. This…

The association between high recreational physical activity and physical activity as a part of daily living in adolescents and availability of local indoor sports facilities and sports clubs.

PubMed

Niclasen, Birgit; Petzold, Max; Schnohr, Christina W

2012-11-01

The aim of this study was to examine how vigorous physical activity (recreational physical activity) (VPA) and moderate to vigorous physical activity as a part of daily life (MVPA) is associated with structural characteristics (availability of sports facilities and sports clubs with child members) in Greenlandic adolescents. Data from the 2006 Health Behaviour in School-aged Children survey including 2,430 children aged 11-17 years was used. Logistic regression models were developed with dichotomous measures on VPA and MVPA as outcomes, number of indoor sports facilities and of sports clubs with child members as independent variables, and adjusted for age, gender, family affluence (FAS), and type of habitation (capital, town or village). High VPA increased with access to indoor facilities, while high MVPA was less likely (odds ratio (OR) 0.54 (0.42-0.70)) if indoor sports facilities were present, both unadjusted and adjusted. Access to a local sports club increased OR for high VPA both unadjusted and adjusted to about 2.3 for five or more clubs, while access to sports clubs was not associated with unadjusted MVPA, negatively associated if adjusted for age, gender and FAS but positively associated if also adjusted for indoor sports facilities. Access to indoor sports facilities itself had a positive association with high VPA, but was persistently negatively associated with high MVPA. Presence of sports clubs with child members was positively associated with high VPA while the association with high MVPA was more complex. The findings have implications for public health planning.

High pressure as a probe of the solid state

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruoff, A.L.

1994-07-10

It is a great pleasure and honor to receive the Percy Williams Bridgman Award. Henry Eyring, my Ph.D. advisor, instilled in me a desire to unravel the secrets of nature in the chemical and physical world. He continued what my mother had begun. From my father I learned the virtue and satisfaction of hard work. In reading Percy Bridgman's [ital The] [ital Physics] [ital of] [ital High] [ital Pressure] [1] after I came to Cornell, I became intrigued by the high-pressure variable, so I owe much to him. I received valuable assistance and encouragement from George Kennedy and Harry Drickamermore » (the first winner of the Bridgman Award) and later from Alvin Van Valkenburg (a co-inventor with three others of the diamond anvil cell). Most importantly, I received encouragement from my wife, Enid Seaton Ruoff, to carry out what is sometimes the arduous pursuit of science---a pursuit that involves long working hours---and I want especially to thank her. [copyright] 1994 American Institute of Physics« less

Appearance-based rejection sensitivity: implications for mental and physical health, affect, and motivation.

PubMed

Park, Lora E

2007-04-01

Appearance-Based Rejection Sensitivity (Appearance-RS) is a personality-processing system characterized by anxious concerns and expectations about being rejected based on one's physical attractiveness. People differ in their sensitivity to rejection based on appearance, with consequences for mental and physical health, self-esteem, affect, and feelings of belonging. Study 1 describes the development and validation of the Appearance-RS scale, its relation to personality variables and to health-related outcomes. Study 2 provides experimental evidence that high Appearance-RS people feel more alone and rejected when asked to think about negative aspects of their appearance. Finally, Study 3 tests ways to reduce the negative effects of receiving an appearance threat among high Appearance-RS participants. Specifically, high Appearance-RS participants who engaged in self-affirmation (thought of their personal strengths) or received a secure attachment prime (thought of a close, caring relationship) were buffered from the negative effects of an appearance threat on subsequent state self-esteem and mood.

Perspectives on Stress, Parenting, and Children's Obesity-Related Behaviors in Black Families.

PubMed

Parks, Elizabeth P; Kazak, Anne; Kumanyika, Shiriki; Lewis, Lisa; Barg, Frances K

2016-12-01

Objective In an effort to develop targets for childhood obesity interventions in non-Hispanic-Black (Black) families, this study examined parental perceptions of stress and identified potential links among parental stress and children's eating patterns, physical activity, and screen-time. Method Thirty-three self-identified Black parents or grandparents of a child aged 3 to 7 years were recruited from a large, urban Black church to participate in semistructured interviews. Interviews were audio-recorded, transcribed, and analyzed using thematic analysis. Results Parents/grandparents described a pathway between how stress affected them personally and their child's eating, structured (sports/dance) and unstructured (free-play) physical activity, and screen-time usage, as well as strategies to prevent this association. Five themes emerged: stress affects parent behaviors related to food and physical activity variably; try to be healthy even with stress; parent/grandparent stress eating and parenting; stress influences family cooking, food choices, and child free-play; and screen-time use to decrease parent stress. Negative parent/grandparent response to their personal stress adversely influenced food purchases and parenting related to child eating, free-play, and screen-time. Children of parents/grandparents who ate high-fat/high-sugar foods when stressed requested these foods. In addition to structured physical activity, cooking ahead and keeping food in the house were perceived to guard against the effects of stress except during parent cravings. Parent/child screen-time helped decrease parent stress. Conclusion Parents/grandparents responded variably to stress which affected the child eating environment, free-play, and screen-time. Family-based interventions to decrease obesity in Black children should consider how stress influences parents. Targeting parent cravings and coping strategies that utilize structure in eating and physical activity may be useful intervention strategies. © 2016 Society for Public Health Education.

Associations of physical activity energy expenditure with nutritional-inflammatory markers in hemodialysis patients.

PubMed

Santos, Clarcson P; Silva, Luciana F; Lopes, Marcelo B; Martins, Márcia T S; Kraychete, Angiolina C; Silva, Fernanda A; Martins, Maria T S; Matos, Cácia M; Lopes, Gildete B; Lopes, Antonio A

2017-11-24

Sedentariness, high inflammation status and malnutrition are highly prevalent in end-stage kidney disease patients on maintenance hemodialysis (MHD). This study investigated associations of weekly physical activity energy expenditure (PAEE) with clinical and anthropometric markers of nutrition and inflammation. The analysis was performed using baseline cross-sectional data of 640 patients enrolled in the prospective cohort "The Prospective Study of the Prognosis of Patients Treated Chronically by Hemodialysis" (PROHEMO) developed in Salvador, BA, Brazil. The long version of the International Physical Activity Questionnaire was used to determine a summary measure of PAEE, the metabolic equivalent of task (MET), taking into account physical activities related to occupation, recreation, travel, sports, and housework. PAEE was the predictor variable. To assess associations of PAEE with outcomes, the sex-age-specific median MET was used. The malnutrition-inflammation score (MIS) with range of 0 to 30 (higher is worse), conicity index as indicator of abdominal adiposity and C-reactive protein (CRP) were the nutritional-inflammatory outcomes. The mean age of the patients was 48.9 ± 13.8 y, 60.3% were males, 16.7% diabetic, 88.1% nonwhite. In multivariable logistic regression models with adjustments for sociodemographic variables and comorbidities, PAEE ≤median was associated with MIS ≥6 (odds ratio [OR] = 1.57; 95% confidence interval [CI] = 1.08, 2.29), conicity index ≥1.3 (OR = 1.52, 95% CI = 1.03, 2.23) and CRP >1.30 mg/dL (OR = 1.69, 95% CI = 1.08, 2.84). Greater physical activity assessed by PAEE was associated with indicators of better nutritional and inflammation status. These results indicate opportunities for improving outcomes in MHD patients by counseling and treatment intervention.

Perspectives on Stress, Parenting, and Children’s Obesity-Related Behaviors in Black Families

PubMed Central

Parks, Elizabeth P.; Kazak, Anne; Kumanyika, Shiriki; Lewis, Lisa; Barg, Frances K.

2016-01-01

Objective In an effort to develop targets for childhood obesity interventions in non-Hispanic-Black (Black) families, this study examined parental perceptions of stress and identified potential links among parental stress and children’s eating patterns, physical activity, and screen-time. Method Thirty-three self-identified Black parents or grandparents of a child aged 3 to 7 years were recruited from a large, urban Black church to participate in semistructured interviews. Interviews were audio-recorded, transcribed, and analyzed using thematic analysis. Results Parents/grandparents described a pathway between how stress affected them personally and their child’s eating, structured (sports/dance) and unstructured (free-play) physical activity, and screen-time usage, as well as strategies to prevent this association. Five themes emerged: stress affects parent behaviors related to food and physical activity variably; try to be healthy even with stress; parent/grandparent stress eating and parenting; stress influences family cooking, food choices, and child free-play; and screen-time use to decrease parent stress. Negative parent/grandparent response to their personal stress adversely influenced food purchases and parenting related to child eating, free-play, and screen-time. Children of parents/grandparents who ate high-fat/high-sugar foods when stressed requested these foods. In addition to structured physical activity, cooking ahead and keeping food in the house were perceived to guard against the effects of stress except during parent cravings. Parent/child screen-time helped decrease parent stress. Conclusion Parents/grandparents responded variably to stress which affected the child eating environment, free-play, and screen-time. Family-based interventions to decrease obesity in Black children should consider how stress influences parents. Targeting parent cravings and coping strategies that utilize structure in eating and physical activity may be useful intervention strategies. PMID:26733488

Built Environment, Adiposity, and Physical Activity in Adults Aged 50–75

PubMed Central

Li, Fuzhong; Harmer, Peter A.; Cardinal, Bradley J.; Bosworth, Mark; Acock, Alan; Johnson-Shelton, Deborah; Moore, Jane M.

2008-01-01

Background Few studies have investigated the built environment and its association with health—especially excess adiposity—and physical activity in the immediate pre-Baby Boom/early-Baby Boom generations, soon to be the dominant demographic in the U.S. The purpose of this study was to examine this relationship. Methods This study used a cross-sectional, multilevel design with neighborhoods as the primary sampling unit (PSU). Residents (N=1221; aged 50–75) were recruited from 120 neighborhoods in Portland OR. The independent variables at the PSU level involved GIS-derived measures of land-use mix, distribution of fast-food outlets, street connectivity, access to public transportation, and green and open spaces. Dependent variables included resident-level measures of excess adiposity (BMI ≥25), three walking activities, and physical activity. Data were collected in 2006–2007 and analyzed in 2007. Results Each unit (i.e., 10%) increase in land-use mix was associated with a 25% reduction in the prevalence of overweight/obesity. However, a 1-SD increase in the density of fast-food outlets was associated with a 7% increase in overweight/obesity. Higher mixed-use land was positively associated with all three types of walking activities and the meeting of physical activity recommendations. Neighborhoods with high street connectivity, high density of public transit stations, and green and open spaces were related in varying degrees to walking and the meeting of physical activity recommendations. The analyses adjusted for neighborhood- and resident-level sociodemographic characteristics. Conclusions Findings suggest the need for public health and city planning officials to address modifiable neighborhood-level, built-environment characteristics to create more livable residential communities aimed at both addressing factors that may influence unhealthy eating and promoting active, healthy lifestyles in this rapidly growing population. PMID:18541175

Competition Level Not Associated With Diet Quality in Marching Artists.

PubMed

McConnell, Colleen; McPherson, Alyssa; Woolf, Kathleen

2018-01-01

Marching artists are a unique group of athletes whose performance can be influenced by nutrition. Because physical demands are thought to be moderate to high, adequate energy and a variety of nutrient-dense foods are needed. The purpose of this study was to examine diet quality, physical activity, and eating behavior of marching artists across elite and nonelite competition levels. This cross-sectional analysis used the validated National Cancer Institute Diet History Questionnaire II, International Physical Activity Questionnaire, and Eating Behavior Patterns Questionnaire. Diet quality was assessed using the Healthy Eating Index (HEI) 2010. Marching artists who participated in marching band in 2015 were eligible. Those in Drum Corps International (DCI) were considered part of the elite level; all others were considered nonelite. Chi-square analyses assessed associations between categorical variables and competition level, and independent sample t-tests assessed differences between continuous variables among competition level. Participants (n = 323) included 228 (71%) DCI members and 95 (29%) non-DCI members who reported a mean age of 19.8 ± 1.9 years. DCI members reported higher physical activity levels (p < 0.001) and fewer meal-skipping behaviors compared to non-DCI members (p < 0.001). The overall mean HEI score was 58.8 ± 10.3, with no difference between competition levels. Only one participant overall (<1%) met the recommended intake level of whole grains. Additionally, 2% of participants met the sodium restriction recommendation and 7% met the empty calorie upper limit. Suboptimal diet quality combined with high levels of physical activity is a problem for marching artists that should be addressed through carefully planned interventions.

Using Empirical Orthogonal Teleconnections to Analyze Interannual Precipitation Variability in China

NASA Astrophysics Data System (ADS)

Stephan, C.; Klingaman, N. P.; Vidale, P. L.; Turner, A. G.; Demory, M. E.; Guo, L.

2017-12-01

Interannual rainfall variability in China affects agriculture, infrastructure and water resource management. A consistent and objective method, Empirical Orthogonal Teleconnection (EOT) analysis, is applied to precipitation observations over China in all seasons. Instead of maximizing the explained space-time variance, the method identifies regions in China that best explain the temporal variability in domain-averaged rainfall. It produces known teleconnections, that include high positive correlations with ENSO in eastern China in winter, along the Yangtze River in summer, and in southeast China during spring. New findings include that variability along the southeast coast in winter, in the Yangtze valley in spring, and in eastern China in autumn, are associated with extratropical Rossby wave trains. The same analysis is applied to six climate simulations of the Met Office Unified Model with and without air-sea coupling and at various horizontal resolutions of 40, 90 and 200 km. All simulations reproduce the observed patterns of interannual rainfall variability in winter, spring and autumn; the leading pattern in summer is present in all but one simulation. However, only in two simulations are all patterns associated with the observed physical mechanism. Coupled simulations capture more observed patterns of variability and associate more of them with the correct physical mechanism, compared to atmosphere-only simulations at the same resolution. Finer resolution does not improve the fidelity of these patterns or their associated mechanisms. Evaluating climate models by only geographical distribution of mean precipitation and its interannual variance is insufficient; attention must be paid to associated mechanisms.

A new variable-resolution associative memory for high energy physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Annovi, A.; Amerio, S.; Beretta, M.

2011-07-01

We describe an important advancement for the Associative Memory device (AM). The AM is a VLSI processor for pattern recognition based on Content Addressable Memory (CAM) architecture. The AM is optimized for on-line track finding in high-energy physics experiments. Pattern matching is carried out by finding track candidates in coarse resolution 'roads'. A large AM bank stores all trajectories of interest, called 'patterns', for a given detector resolution. The AM extracts roads compatible with a given event during detector read-out. Two important variables characterize the quality of the AM bank: its 'coverage' and the level of fake roads. The coverage,more » which describes the geometric efficiency of a bank, is defined as the fraction of tracks that match at least one pattern in the bank. Given a certain road size, the coverage of the bank can be increased just adding patterns to the bank, while the number of fakes unfortunately is roughly proportional to the number of patterns in the bank. Moreover, as the luminosity increases, the fake rate increases rapidly because of the increased silicon occupancy. To counter that, we must reduce the width of our roads. If we decrease the road width using the current technology, the system will become very large and extremely expensive. We propose an elegant solution to this problem: the 'variable resolution patterns'. Each pattern and each detector layer within a pattern will be able to use the optimal width, but we will use a 'don't care' feature (inspired from ternary CAMs) to increase the width when that is more appropriate. In other words we can use patterns of variable shape. As a result we reduce the number of fake roads, while keeping the efficiency high and avoiding excessive bank size due to the reduced width. We describe the idea, the implementation in the new AM design and the implementation of the algorithm in the simulation. Finally we show the effectiveness of the 'variable resolution patterns' idea using simulated high occupancy events in the ATLAS detector. (authors)« less

Reliability of Wearable Inertial Measurement Units to Measure Physical Activity in Team Handball.

PubMed

Luteberget, Live S; Holme, Benjamin R; Spencer, Matt

2018-04-01

To assess the reliability and sensitivity of commercially available inertial measurement units to measure physical activity in team handball. Twenty-two handball players were instrumented with 2 inertial measurement units (OptimEye S5; Catapult Sports, Melbourne, Australia) taped together. They participated in either a laboratory assessment (n = 10) consisting of 7 team handball-specific tasks or field assessment (n = 12) conducted in 12 training sessions. Variables, including PlayerLoad™ and inertial movement analysis (IMA) magnitude and counts, were extracted from the manufacturers' software. IMA counts were divided into intensity bands of low (1.5-2.5 m·s -1 ), medium (2.5-3.5 m·s -1 ), high (>3.5 m·s -1 ), medium/high (>2.5 m·s -1 ), and total (>1.5 m·s -1 ). Reliability between devices and sensitivity was established using coefficient of variation (CV) and smallest worthwhile difference (SWD). Laboratory assessment: IMA magnitude showed a good reliability (CV = 3.1%) in well-controlled tasks. CV increased (4.4-6.7%) in more-complex tasks. Field assessment: Total IMA counts (CV = 1.8% and SWD = 2.5%), PlayerLoad (CV = 0.9% and SWD = 2.1%), and their associated variables (CV = 0.4-1.7%) showed a good reliability, well below the SWD. However, the CV of IMA increased when categorized into intensity bands (2.9-5.6%). The reliability of IMA counts was good when data were displayed as total, high, or medium/high counts. A good reliability for PlayerLoad and associated variables was evident. The CV of the previously mentioned variables was well below the SWD, suggesting that OptimEye's inertial measurement unit and its software are sensitive for use in team handball.

Physical Activity and Safety From Crime Among Adults: A Systematic Review.

PubMed

da Silva, Inacio C; Payne, Valerie L; Hino, Adriano Akira; Varela, Andrea Ramirez; Reis, Rodrigo S; Ekelund, Ulf; Hallal, Pedro C

2016-06-01

The aim of this study was to review the evidence to date on the association between physical activity and safety from crime. Articles with adult populations of 500+ participants investigating the association between physical activity and safety from crime were included. A methodological quality assessment was conducted using an adapted version of the Downs and Black checklist. The literature search identified 15,864 articles. After assessment of titles, abstracts and full-texts, 89 articles were included. Most articles (84.3%) were derived from high-income countries and only 3 prospective articles were identified. Articles presented high methodological quality. In 38 articles (42.7%), at least one statistically significant association in the expected direction was reported (ie, safety from crime was positively associated with physical activity). Nine articles (10.1%) found an association in the unexpected direction and 42 (47.2%) did not find statistically significant associations. The results did not change when we analyzed articles separately by sex, age, type of measurement, or domains of physical activity evaluated. The current evidence, mostly based on cross-sectional studies, suggests a lack of association between physical activity and safety from crime. Prospective studies and natural experiments are needed, particularly in areas with wide crime variability.

Student understanding of control of variables: Deciding whether or not a variable influences the behavior of a system

NASA Astrophysics Data System (ADS)

Boudreaux, Andrew; Shaffer, Peter S.; Heron, Paula R. L.; McDermott, Lillian C.

2008-02-01

The ability of adult students to reason on the basis of the control of variables was the subject of an extended investigation. This paper describes the part of the study that focused on the reasoning required to decide whether or not a given variable influences the behavior of a system. The participants were undergraduates taking introductory Physics and K-8 teachers studying physics and physical science in inservice institutes and workshops. Although most of the students recognized the need to control variables, many had significant difficulty with the underlying reasoning. The results indicate serious shortcomings in the preparation of future scientists and in the education of a scientifically literate citizenry. There are also strong implications for the professional development of teachers, many of whom are expected to teach control of variables to young students.

Causal modeling of secondary science students' intentions to enroll in physics

NASA Astrophysics Data System (ADS)

Crawley, Frank E.; Black, Carolyn B.

The purpose of this study was to explore the utility of the theory of planned behavior model developed by social psychologists for understanding and predicting the behavioral intentions of secondary science students regarding enrolling in physics. In particular, the study used a three-stage causal model to investigate the links from external variables to behavioral, normative, and control beliefs; from beliefs to attitudes, subjective norm, and perceived behavioral control; and from attitudes, subjective norm, and perceived behavioral control to behavioral intentions. The causal modeling method was employed to verify the underlying causes of secondary science students' interest in enrolling physics as predicted in the theory of planned behavior. Data were collected from secondary science students (N = 264) residing in a central Texas city who were enrolled in earth science (8th grade), biology (9th grade), physical science (10th grade), or chemistry (11th grade) courses. Cause-and-effect relationships were analyzed using path analysis to test the direct effects of model variables specified in the theory of planned behavior. Results of this study indicated that students' intention to enroll in a high school physics course was determined by their attitude toward enrollment and their degree of perceived behavioral control. Attitude, subjective norm, and perceived behavioral control were, in turn, formed as a result of specific beliefs that students held about enrolling in physics. Grade level and career goals were found to be instrumental in shaping students' attitude. Immediate family members were identified as major referents in the social support system for enrolling in physics. Course and extracurricular conflicts and the fear of failure were shown to be the primary beliefs obstructing students' perception of control over physics enrollment. Specific recommendations are offered to researchers and practitioners for strengthening secondary school students' intentions to study physics.

Patterns in Temporal Variability of Temperature, Oxygen and pH along an Environmental Gradient in a Coral Reef

PubMed Central

Guadayol, Òscar; Silbiger, Nyssa J.; Donahue, Megan J.; Thomas, Florence I. M.

2014-01-01

Spatial and temporal environmental variability are important drivers of ecological processes at all scales. As new tools allow the in situ exploration of individual responses to fluctuations, ecologically meaningful ways of characterizing environmental variability at organism scales are needed. We investigated the fine-scale spatial heterogeneity of high-frequency temporal variability in temperature, dissolved oxygen concentration, and pH experienced by benthic organisms in a shallow coastal coral reef. We used a spatio-temporal sampling design, consisting of 21 short-term time-series located along a reef flat-to-reef slope transect, coupled to a long-term station monitoring water column changes. Spectral analyses revealed sharp gradients in variance decomposed by frequency, as well as differences between physically-driven and biologically-reactive parameters. These results highlight the importance of environmental variance at organismal scales and present a new sampling scheme for exploring this variability in situ. PMID:24416364

Technology Assessment for Large Vertical-Lift Transport Tiltrotors

NASA Technical Reports Server (NTRS)

Germanowski, Peter J.; Stille, Brandon L.; Strauss, Michael P.

2010-01-01

The technical community has identified rotor efficiency as a critical enabling technology for large vertical-lift transport (LVLT) rotorcraft. The size and performance of LVLT aircraft will be far beyond current aircraft capabilities, enabling a transformational change in cargo transport effectiveness. Two candidate approaches for achieving high efficiency were considered for LVLT applications: a variable-diameter tiltrotor (VDTR) and a variable-speed tiltrotor (VSTR); the former utilizes variable-rotor geometry and the latter utilizes variable-rotor speed. Conceptual aircraft designs were synthesized for the VDTR and VSTR and compared to a conventional tiltrotor (CTR). The aircraft were optimized to a common objective function and bounded by a set of physical- and requirements-driven constraints. The resulting aircraft were compared for weight, size, performance, handling qualities, and other attributes. These comparisons established a measure of the relative merits of the variable-diameter and -speed rotor systems as enabling technologies for LVLT capability.

Spatialization of Brazilian pig production: relationship between productive, physical, environmental, and socio-economic variables.

PubMed

da Silva, Isabel C M; Bremm, Bárbara; Teixeira, Jennifer L; Costa, Nathalia S; Barcellos, Júlio O J; Braccini, José; Cesconeto, Robson J; McManus, Concepta

2017-06-01

Brazilian pig production spans over a large territory encompassing regions of different climatic and socio-economic realities. Production, physical, socio-economic, and environmental data were used to characterize pig production in the country. Multivariate analysis evaluated indices including number productivity, production levels, and income from pigs, together with the average area of pig farm and socio-economic variables such as municipal human development index, technical guidance received from agricultural cooperatives and industrial companies, number of family farms, and offtake; and finally, environmental variables: latitude, longitude, annual temperature range, solar radiation index, as well as temperature and humidity index. The Southern region has the largest herd, number of pigs sold/sow, and offtake rate (p < 0.05), followed by the Midwest and Southeast. No significant correlations were seen between production rates and productivity with the socio-economic and environmental variables in the regions of Brazil. Production indexes, productivity, and offtake rate discriminated Northeast and Midwest and Northeast and Southeast regions. The Northern region, with a large area, has few and far-between farms that rear pigs for subsistence. The Northeast region has large herds, but low productivity. Number of slaughtered pigs has been variable over the past three decades, with few states responsible for maintaining high production in Brazil. However, the activity can be effective in any region of the country with technology and technical assistance adapted to regional characteristics.

Comparisons of Selected Student and Teacher Variables in All-Girls and Coeducational Physical Education Environments

ERIC Educational Resources Information Center

Derry, Julie A.; Phillips, D. Allen

2004-01-01

The purpose of this study was to investigate selected student and teacher variables and compare the differences between these variables for female students and female teachers in coeducation and single-sex physical education classes. Eighteen female teachers and intact classes were selected; 9 teachers from coeducation and 9 teachers from…

On the relation of earthquake stress drop and ground motion variability

NASA Astrophysics Data System (ADS)

Oth, Adrien; Miyake, Hiroe; Bindi, Dino

2017-07-01

One of the key parameters for earthquake source physics is stress drop since it can be directly linked to the spectral level of ground motion. Stress drop estimates from moment corner frequency analysis have been shown to be extremely variable, and this to a much larger degree than expected from the between-event ground motion variability. This discrepancy raises the question whether classically determined stress drop variability is too large, which would have significant consequences for seismic hazard analysis. We use a large high-quality data set from Japan with well-studied stress drop data to address this issue. Nonparametric and parametric reference ground motion models are derived, and the relation of between-event residuals for Japan Meteorological Agency equivalent seismic intensity and peak ground acceleration with stress drop is analyzed for crustal earthquakes. We find a clear correlation of the between-event residuals with stress drops estimates; however, while the island of Kyushu is characterized by substantially larger stress drops than Honshu, the between-event residuals do not reflect this observation, leading to the appearance of two event families with different stress drop levels yet similar range of between-event residuals. Both the within-family and between-family stress drop variations are larger than expected from the ground motion between-event variability. A systematic common analysis of these parameters holds the potential to provide important constraints on the relative robustness of different groups of data in the different parameter spaces and to improve our understanding on how much of the observed source parameter variability is likely to be true source physics variability.

Observed ground-motion variabilities and implication for source properties

NASA Astrophysics Data System (ADS)

Cotton, F.; Bora, S. S.; Bindi, D.; Specht, S.; Drouet, S.; Derras, B.; Pina-Valdes, J.

2016-12-01

One of the key challenges of seismology is to be able to calibrate and analyse the physical factors that control earthquake and ground-motion variabilities. Within the framework of empirical ground-motion prediction equation (GMPE) developments, ground-motions residuals (differences between recorded ground motions and the values predicted by a GMPE) are computed. The exponential growth of seismological near-field records and modern regression algorithms allow to decompose these residuals into between-event and a within-event residual components. The between-event term quantify all the residual effects of the source (e.g. stress-drops) which are not accounted by magnitude term as the only source parameter of the model. Between-event residuals provide a new and rather robust way to analyse the physical factors that control earthquake source properties and associated variabilities. We first will show the correlation between classical stress-drops and between-event residuals. We will also explain why between-event residuals may be a more robust way (compared to classical stress-drop analysis) to analyse earthquake source-properties. We will finally calibrate between-events variabilities using recent high-quality global accelerometric datasets (NGA-West 2, RESORCE) and datasets from recent earthquakes sequences (Aquila, Iquique, Kunamoto). The obtained between-events variabilities will be used to evaluate the variability of earthquake stress-drops but also the variability of source properties which cannot be explained by a classical Brune stress-drop variations. We will finally use the between-event residual analysis to discuss regional variations of source properties, differences between aftershocks and mainshocks and potential magnitude dependencies of source characteristics.

Optimism, well-being, depressive symptoms, and perceived physical health: a study among Stroke survivors.

PubMed

Shifren, Kim; Anzaldi, Kristen

2018-01-01

The investigation of the relation of positive personality characteristics to mental and physical health among Stroke survivors has been a neglected area of research. The purpose of this study was to examine the relationship between optimism, well-being, depressive symptoms, and perceived physical health among Stroke survivors. It was hypothesized that Stroke survivors' optimism would explain variance in their physical health above and beyond the variance explained by demographic variables, diagnostic variables, and mental health. One hundred seventy-six Stroke survivors (97 females, 79 males) completed the Revised Life Orientation Test, the Center for Epidemiological Studies Depression Scale, two items on perceived physical health from the 36-item Short Form of the Medical Outcomes study, and the Identity scale of the Illness Perception Questionnaire. Pearson correlations, hierarchical regression analyses, and the PROCESS approach to determining mediators were used to assess hypothesized relations between variables. Stroke survivors' level of optimism explained additional variance in overall health in regression models controlling for demographic and diagnostic variables, and mental health. Analyses revealed that optimism played a partial mediator role between mental health (well-being, depressive symptoms and total score on CES-D) variables and overall health.

Critical success factors for physical activity promotion through community partnerships.

PubMed

Lucidarme, Steffie; Marlier, Mathieu; Cardon, Greet; De Bourdeaudhuij, Ilse; Willem, Annick

2014-02-01

To define key factors of effective evidence-based policy implementation for physical activity promotion by use of a partnership approach. Using Parent and Harvey's model for sport and physical activity community-based partnerships, we defined determinants of implementation based on 13 face-to-face interviews with network organisations and 39 telephone interviews with partner organisations. Furthermore, two quantitative data-sets (n = 991 and n = 965) were used to measure implementation. In total, nine variables were found to influence implementation. Personal contact was the most powerful variable since its presence contributed to success while its absence led to a negative outcome. Four contributed directly to success: political motive, absence of a metropolis, high commitment and more qualified staff. Four others resulted in a less successful implementation: absence of positive merger effects, exposure motive and governance, and dispersed leadership. Community networks are a promising instrument for the implementation of evidence-based policies. However, determinants of both formation and management of partnerships influence the implementation success. During partnership formation, special attention should be given to partnership motives while social skills are of utmost importance for the management.

Relationship between performance variables and baseball ability in youth baseball players.

PubMed

Nakata, Hiroki; Nagami, Tomoyuki; Higuchi, Takatoshi; Sakamoto, Kiwako; Kanosue, Kazuyuki

2013-10-01

The present study investigated the relationship of performance variables and anthropometric measurements on baseball ability in 164 youth baseball players (age: 6.4-15.7 years). To evaluate their baseball performance, ball speeds in pitching and batting were recorded and kinetic energies of the pitched and hit balls were calculated. To record anthropometric and physical fitness characteristics, height and weight were measured and a battery of physical fitness tests covering standing long jump, side steps, sit-ups, 10-m sprint, trunk flexion, back strength, and grip strengths of both hands were conducted. The results of a multiple regression analysis revealed several significant predictors: age, body mass index (BMI), standing long jump, 10-m sprint, and grip strength for pitched ball kinetic energy and age, BMI, standing long jump, and back strength for hit ball kinetic energy. This study provides scientific evidence that relates certain specific physical performance tests and body characteristics with high achievement in the actual performance of pitching and batting. Youth players, their parents, coaches, and trainers would benefit by addressing these characteristics when planning training programs to improve the baseball performance of youth players.

Variability in oceanographic barriers to coral larval dispersal: Do currents shape biodiversity?

NASA Astrophysics Data System (ADS)

Thompson, D. M.; Kleypas, J.; Castruccio, F.; Curchitser, E. N.; Pinsky, M. L.; Jönsson, B.; Watson, J. R.

2018-07-01

The global center of marine biodiversity is located in the western tropical Pacific in a region known as the "Coral Triangle" (CT). This region is also considered the most threatened of all coral reef regions, because multiple impacts, including rising temperatures and coral bleaching, have already caused high mortality of reef corals over large portions of the CT. Larval dispersal and recruitment play a critical role in reef recovery after such disturbances, but our understanding of reproductive connectivity between reefs is limited by a paucity of observations. Oceanographic modeling can provide an economical and efficient way to augment our understanding of reef connectivity, particularly over an area as large as the CT, where marine ecosystem management has become a priority. This work combines daily averaged surface current velocity and direction from a Regional Ocean Modeling System developed for the CT region (CT-ROMS) with a Lagrangian particle tracking tool (TRACMASS) to investigate the probability of larval transport between reefs for a typical broadcasting coral. A 47-year historical simulation (1960-2006) was used to analyze the potential connectivity, the physical drivers of larval transport, and its variability following bi-annual spawning events in April and September. Potential connectivity between reefs was highly variable from year to year, emphasizing the need for long simulations. The results suggest that although reefs in this region are highly self-seeded, comparatively rare long-distance dispersal events may play a vital role in shaping regional patterns of reef biodiversity and recovery following disturbance. The spatial pattern of coral "subpopulations," which are based on the potential connectivity between reefs, agrees with observed regional-scale patterns of biodiversity, suggesting that the physical barriers to larval dispersal are a first-order driver of coral biodiversity in the CT region. These physical barriers persist through the 21st Century when the model is forced with the Community Earth System Model (CESM) RCP8.5 climate scenario, despite some regional changes in connectivity between reefs.

Responses of aquatic organisms to metal pollution in a lowland river in Flanders: a comparison of diatoms and macroinvertebrates.

PubMed

De Jonge, Maarten; Van de Vijver, Bart; Blust, Ronny; Bervoets, Lieven

2008-12-15

The role of macroinvertebrates and diatoms as indicator for metal pollution was investigated by assessing both biota along a metal gradient in the Belgian river the Dommel. Macroinvertebrates and diatoms were sampled in summer and winter and physical-chemical characteristics of the water were measured at four different sample periods and related to sediment characteristics. Although metal concentrations, except cadmium, in the water nowhere exceeded water quality standards, high metal concentrations were measured in the sediment, indicating historical contamination of the Dommel. At the sites that were situated downstream of the pollution source, high levels of conductivity and chloride were measured in the water. Redundancy Analysis (RDA) indicated pH, phosphate and zinc as the significant environmental variables explaining each respectively 7.7%, 11.6% and 22.6% of the macroinvertebrate community composition. Two clusters could be separated, with Gammarus pulex, Leptocerus interruptus, Baetis rhodani and Cloeon dipterum associated with low zinc concentrations and Tubificidae, Asellus aquaticus, Erpobdella sp. and Chironomus thummi-plumosus associated with higher zinc concentrations. Ammonium (10.6%), conductivity (16.5%), chloride (11.4%) and zinc (5.9%) turned out to be significant variables explaining the diatom community structure. Based on physical-chemical differences and species composition, three different groups could be separated. With this Tabellaria flocculosa and Fragilaria capucina var. rumpens were associated with low metal concentrations, Gomphonema parvulum and Nitzschia palea with elevated concentrations and Eolimna minima and Sellaphora seminulum with high zinc concentrations. In conclusion, the diatom community best reflected the metal gradient. With regard to water quality indices, those based on macroinvertebrates best followed the metal pollution gradient and were most strongly correlated with physical-chemical variables of water and sediment. This study indicated that to assess the effect of metal pollution in lowland rivers, the combined use of macroinvertebrates and diatoms is more appropriate than the use of both biota separately.

Statistical methods for biodosimetry in the presence of both Berkson and classical measurement error

NASA Astrophysics Data System (ADS)

Miller, Austin

In radiation epidemiology, the true dose received by those exposed cannot be assessed directly. Physical dosimetry uses a deterministic function of the source term, distance and shielding to estimate dose. For the atomic bomb survivors, the physical dosimetry system is well established. The classical measurement errors plaguing the location and shielding inputs to the physical dosimetry system are well known. Adjusting for the associated biases requires an estimate for the classical measurement error variance, for which no data-driven estimate exists. In this case, an instrumental variable solution is the most viable option to overcome the classical measurement error indeterminacy. Biological indicators of dose may serve as instrumental variables. Specification of the biodosimeter dose-response model requires identification of the radiosensitivity variables, for which we develop statistical definitions and variables. More recently, researchers have recognized Berkson error in the dose estimates, introduced by averaging assumptions for many components in the physical dosimetry system. We show that Berkson error induces a bias in the instrumental variable estimate of the dose-response coefficient, and then address the estimation problem. This model is specified by developing an instrumental variable mixed measurement error likelihood function, which is then maximized using a Monte Carlo EM Algorithm. These methods produce dose estimates that incorporate information from both physical and biological indicators of dose, as well as the first instrumental variable based data-driven estimate for the classical measurement error variance.

Physical activity and body image among men and boys: A meta-analysis.

PubMed

Bassett-Gunter, Rebecca; McEwan, Desmond; Kamarhie, Aria

2017-09-01

Three meta-analytic reviews have concluded that physical activity is positively related to body image. Historically, research regarding physical activity and body image has been disproportionately focused on female samples. For example, the most recent meta-analysis (2009) extracted 56 effect sizes for women and only 12 for men. The current paper provides an update to the literature regarding the relationship between physical activity and body image among men and boys across 84 individual effect sizes. The analysis also provides insight regarding moderator variables including participant age, and physical activity type and intensity. Overall, physical activity was positively related to body image among men and boys with various moderator variables warranting further investigation. Pragmatic implications are discussed as well as the limitations within existing research and need for additional research to further understand moderator and mediator variables. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical restraints in an Italian psychiatric ward: clinical reasons and staff organization problems.

PubMed

Di Lorenzo, Rosaria; Baraldi, Sara; Ferrara, Maria; Mimmi, Stefano; Rigatelli, Marco

2012-04-01

To analyze physical restraint use in an Italian acute psychiatric ward, where mechanical restraint by belt is highly discouraged but allowed. Data were retrospectively collected from medical and nursing charts, from January 1, 2005, to December 31, 2008. Physical restraint rate and relationships between restraints and selected variables were statistically analyzed. Restraints were statistically significantly more frequent in compulsory or voluntary admissions of patients with an altered state of consciousness, at night, to control aggressive behavior, and in patients with "Schizophrenia and other Psychotic Disorders" during the first 72 hr of hospitalization. Analysis of clinical and organizational factors conditioning restraints may limit its use. © 2011 Wiley Periodicals, Inc.

Correlations Between Optical, Chemical and Physical Properties of Biomass Burn Aerosols

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hopkins, Rebecca J.; Lewis, Keith M.; Dessiaterik, Yury

2007-09-20

Single scattering albedo (ω) and Angstrom absorption coefficient (αap) values are measured at 405, 532 and 870 nm for aerosols generated during controlled laboratory combustion of twelve wildland fuels. Considerable fuel dependent variation in these optical properties is observed at these wavelengths. Complementary microspectroscopy techniques are used to elucidate spatially resolved local chemical bonding, carbon-to-oxygen atomic ratios, percent of sp2 hybridization (graphitic nature), elemental composition, particle size and morphology. These parameters are compared directly with the corresponding optical properties for each combustion product, facilitating an understanding of the fuel dependent variability observed. Results indicate that combustion products can be dividedmore » into three categories based on chemical, physical and optical properties. Only materials displaying a high degree of sp2 hybridization, with chemical and physical properties characteristic of ‘soot’ or black carbon, exhibit ω and αap values that indicate a high light absorbing capacity.« less

Physics-driven Spatiotemporal Regularization for High-dimensional Predictive Modeling: A Novel Approach to Solve the Inverse ECG Problem

NASA Astrophysics Data System (ADS)

Yao, Bing; Yang, Hui

2016-12-01

This paper presents a novel physics-driven spatiotemporal regularization (STRE) method for high-dimensional predictive modeling in complex healthcare systems. This model not only captures the physics-based interrelationship between time-varying explanatory and response variables that are distributed in the space, but also addresses the spatial and temporal regularizations to improve the prediction performance. The STRE model is implemented to predict the time-varying distribution of electric potentials on the heart surface based on the electrocardiogram (ECG) data from the distributed sensor network placed on the body surface. The model performance is evaluated and validated in both a simulated two-sphere geometry and a realistic torso-heart geometry. Experimental results show that the STRE model significantly outperforms other regularization models that are widely used in current practice such as Tikhonov zero-order, Tikhonov first-order and L1 first-order regularization methods.

Screen time by different devices in adolescents: association with physical inactivity domains and eating habits.

PubMed

Delfino, Leandro D; Dos Santos Silva, Diego A; Tebar, William R; Zanuto, Edner F; Codogno, Jamile S; Fernandes, Rômulo A; Christofaro, Diego G

2018-03-01

Sedentary behaviors in adolescents are associated with using screen devices, analyzed as the total daily time in television viewing, using the computer and video game. However, an independent and clustered analysis of devices allows greater understanding of associations with physical inactivity domains and eating habits in adolescents. Sample of adolescents aged 10-17 years (N.=1011) from public and private schools, randomly selected. The use of screen devices was measured by hours per week spent in each device: TV, computer, videogames and mobile phone/tablet. Physical inactivity domains (school, leisure and sports), eating habits (weekly food consumption frequency) and socioeconomic status were assessed by questionnaire. The prevalence of high use of mobile phone/tablet was 70% among adolescents, 63% showed high use of TV or computer and 24% reported high use of videogames. High use of videogames was greater among boys and high use of mobile phone/tablet was higher among girls. Significant associations of high use of TV (OR=1.43, 95% CI: 1.04-1.99), computer (OR=1.44, 95% CI: 1.03-2.02), videogames (OR=1.65, 95% CI: 1.13-2.69) and consumption of snacks were observed. High use of computer was associated with fried foods consumption (OR=1.32, 95% CI: 1.01-1.75) and physical inactivity (OR=1.41, 95% CI: 1.03-1.95). Mobile phone was associated with consumption of sweets (OR=1.33, 95% CI: 1.00-1.80). Cluster using screen devices showed associations with high consumption of snacks, fried foods and sweets, even after controlling for confounding variables. The high use of screen devices was associated with high consumption of snacks, fried foods, sweets and physical inactivity in adolescents.

Complex, Dynamic Combination of Physical, Chemical and Nutritional Variables Controls Spatio-Temporal Variation of Sandy Beach Community Structure

PubMed Central

Ortega Cisneros, Kelly; Smit, Albertus J.; Laudien, Jürgen; Schoeman, David S.

2011-01-01

Sandy beach ecological theory states that physical features of the beach control macrobenthic community structure on all but the most dissipative beaches. However, few studies have simultaneously evaluated the relative importance of physical, chemical and biological factors as potential explanatory variables for meso-scale spatio-temporal patterns of intertidal community structure in these systems. Here, we investigate macroinfaunal community structure of a micro-tidal sandy beach that is located on an oligotrophic subtropical coast and is influenced by seasonal estuarine input. We repeatedly sampled biological and environmental variables at a series of beach transects arranged at increasing distances from the estuary mouth. Sampling took place over a period of five months, corresponding with the transition between the dry and wet season. This allowed assessment of biological-physical relationships across chemical and nutritional gradients associated with a range of estuarine inputs. Physical, chemical, and biological response variables, as well as measures of community structure, showed significant spatio-temporal patterns. In general, bivariate relationships between biological and environmental variables were rare and weak. However, multivariate correlation approaches identified a variety of environmental variables (i.e., sampling session, the C∶N ratio of particulate organic matter, dissolved inorganic nutrient concentrations, various size fractions of photopigment concentrations, salinity and, to a lesser extent, beach width and sediment kurtosis) that either alone or combined provided significant explanatory power for spatio-temporal patterns of macroinfaunal community structure. Overall, these results showed that the macrobenthic community on Mtunzini Beach was not structured primarily by physical factors, but instead by a complex and dynamic blend of nutritional, chemical and physical drivers. This emphasises the need to recognise ocean-exposed sandy beaches as functional ecosystems in their own right. PMID:21858213

Complex, dynamic combination of physical, chemical and nutritional variables controls spatio-temporal variation of sandy beach community structure.

PubMed

Ortega Cisneros, Kelly; Smit, Albertus J; Laudien, Jürgen; Schoeman, David S

2011-01-01

Sandy beach ecological theory states that physical features of the beach control macrobenthic community structure on all but the most dissipative beaches. However, few studies have simultaneously evaluated the relative importance of physical, chemical and biological factors as potential explanatory variables for meso-scale spatio-temporal patterns of intertidal community structure in these systems. Here, we investigate macroinfaunal community structure of a micro-tidal sandy beach that is located on an oligotrophic subtropical coast and is influenced by seasonal estuarine input. We repeatedly sampled biological and environmental variables at a series of beach transects arranged at increasing distances from the estuary mouth. Sampling took place over a period of five months, corresponding with the transition between the dry and wet season. This allowed assessment of biological-physical relationships across chemical and nutritional gradients associated with a range of estuarine inputs. Physical, chemical, and biological response variables, as well as measures of community structure, showed significant spatio-temporal patterns. In general, bivariate relationships between biological and environmental variables were rare and weak. However, multivariate correlation approaches identified a variety of environmental variables (i.e., sampling session, the C∶N ratio of particulate organic matter, dissolved inorganic nutrient concentrations, various size fractions of photopigment concentrations, salinity and, to a lesser extent, beach width and sediment kurtosis) that either alone or combined provided significant explanatory power for spatio-temporal patterns of macroinfaunal community structure. Overall, these results showed that the macrobenthic community on Mtunzini Beach was not structured primarily by physical factors, but instead by a complex and dynamic blend of nutritional, chemical and physical drivers. This emphasises the need to recognise ocean-exposed sandy beaches as functional ecosystems in their own right.

The relationship between history and physical examination findings and the outcome of electrodiagnostic testing in patients with sciatica referred to physical therapy.

PubMed

Savage, Nathan J; Fritz, Julie M; Thackeray, Anne

2014-07-01

Cross-sectional diagnostic accuracy study. To investigate the relationship between history and physical examination findings and the outcome of electrodiagnostic testing in patients with sciatica referred to physical therapy. Electrodiagnostic testing is routinely used to evaluate patients with sciatica. Recent evidence suggests that the presence of radiculopathy identified with electrodiagnostic testing may predict better functional outcomes in these patients. While some patient history and physical examination findings have been shown to predict the presence of disc herniation or neurological insult, little is known about their relationship to the results of electrodiagnostic testing. Electrodiagnostic testing was performed on 38 patients with sciatica who participated in a randomized trial that compared different physical therapy interventions. The diagnostic gold standard was the presence or absence of radiculopathy, based on the results of the needle electromyographic examination. Diagnostic sensitivity and specificity values were calculated, along with corresponding likelihood ratios, for select patient history and physical examination variables. No significant relationship was found between select patient history and physical examination findings, analyzed individually or in combination, and the outcome of electrodiagnostic testing. Diagnostic sensitivity values ranged from 0.03 (95% confidence interval [CI]: 0.00, 0.24) to a high of 0.95 (95% CI: 0.72, 0.99), and specificity values ranged from 0.10 (95% CI: 0.02, 0.34) to a high of 0.95 (95% CI: 0.72, 0.99). Positive likelihood ratios ranged from 0.15 (95% CI: 0.01, 2.87) to a high of 2.33 (95% CI: 0.71, 7.70), and negative likelihood ratios ranged from 2.00 (95% CI: 0.35, 11.48) to a low of 0.50 (95% CI: 0.03, 8.10). In this investigation, the relationship between patient history and physical examination findings and the outcome of electrodiagnostic testing among patients with sciatica was not found to be statistically significant or clinically meaningful. However, given the small sample size and corresponding large CIs, these results should be considered with caution, recognizing that some of the history and physical examination variables may prove useful in future research. These findings suggest that electrodiagnostic testing is essential to identify the subgroup of patients with sciatica who have measurable nerve injury consistent with radiculopathy, which may be an important prognostic factor for recovery. Level of Evidence Diagnosis, level 3b-. J Orthop Sports Phys Ther 2014;44(7):508-517. Epub 22 May 2014. doi:10.2519/jospt.2014.5002.

The effect of teacher quality on the achievement of students in Integrated Physics and Chemistry

NASA Astrophysics Data System (ADS)

Alexander, Rima

For many years, researchers, policy makers, and the education community have explored various school variables and their impact on student achievement (Darling-Hammond, 2000; Ferguson and Womack 1993; Ferguson and Ladd 1996; Rice, 2003; Rockoff, 2003; Rowan, Chiang, and Miller 1997; Sanders and Horn, 1996; Wright Horn and Sanders, 1997). Invariably, the issue of teacher quality arises. Teacher quality is the single most influential factor under school control that affects student achievement (Darling-Hammond, 2000; Rice, 2003; Rockoff, 2003; Sanders and Horn, 1996; Wright Horn and Sanders, 1997). Generally, students taught by highly qualified teachers perform better on standardized tests than students with less qualified teachers (Ferguson and Womack 1993; Ferguson and Ladd 1996; Rowan, Chiang, and Miller 1997). Previous research indicates that teachers indeed matter for the improvement of student achievement, but getting good measures of what is meant by teacher quality is a continuing challenge (Goldhaber, 2002). The purpose of this study was to describe the effect of teacher quality on the achievement of students in Integrated Physics and Chemistry (IPC). In order to achieve this purpose, this study addressed the following research question: chemistry and physics teachers compare to the achievement of students taught by less-qualified IPC teachers? A causal-comparative methodology was employed to address this research question. The independent variable was teacher quality---highly-qualified or less qualified. The teacher attributes that were examined in this study are: (1) teachers' educational background; (2) content knowledge; (3) pedagogical knowledge; and (4) certification. The dependent variable was student achievement in integrated physics and chemistry, as measured by an end-of-course IPC District Assessment of Curriculum, IPC DAC. Descriptive statistics were computed for the independent variable in the study. A Chi Square was performed on the data, utilizing SPSS version 12.0.1 software. Next a test of statistical significance was done to determine whether the null hypothesis could be rejected; and whether or not the research hypothesis could be accepted. Since this is a causal comparative design with only two groups in which student achievement was measured by a test that will yield raw scores, a Chi Square was conducted to determine whether the pass rates of the two groups of students based on obtained and expected percentages were statistically significantly different A Chi Square value of 4.29 was obtained, which indicates that the pass rate for students of highly-qualified teachers was statistically significantly higher than for students of less-qualified teachers. For the purpose of this study a criterion value of (p<.05) was used.

Relationship between insulin resistance-associated metabolic parameters and anthropometric measurements with sugar-sweetened beverage intake and physical activity levels in US adolescents: findings from the 1999-2004 National Health and Nutrition Examination Survey.

PubMed

Bremer, Andrew A; Auinger, Peggy; Byrd, Robert S

2009-04-01

To evaluate the relationship between insulin resistance-associated metabolic parameters and anthropometric measurements with sugar-sweetened beverage intake and physical activity levels. A cross-sectional analysis of the National Health and Nutrition Examination Survey data collected by the National Center for Health Statistics. Nationally representative samples of US adolescents participating in the National Health and Nutrition Examination Survey during the years 1999-2004. A total of 6967 adolescents aged 12 to 19 years. Sugar-sweetened beverage consumption and physical activity levels. Glucose and insulin concentrations, a homeostasis model assessment of insulin resistance (HOMA-IR), total, high-density lipoprotein, and low-density lipoprotein cholesterol concentrations, triglyceride concentrations, systolic and diastolic blood pressure, waist circumference, and body mass index (calculated as weight in kilograms divided by height in meters squared) percentile for age and sex. Multivariate linear regression analyses showed that increased sugar-sweetened beverage intake was independently associated with increased HOMA-IR, systolic blood pressure, waist circumference, and body mass index percentile for age and sex and decreased HDL cholesterol concentrations; alternatively, increased physical activity levels were independently associated with decreased HOMA-IR, low-density lipoprotein cholesterol concentrations, and triglyceride concentrations and increased high-density lipoprotein cholesterol concentrations. Furthermore, low sugar-sweetened beverage intake and high physical activity levels appear to modify each others' effects of decreasing HOMA-IR and triglyceride concentrations and increasing high-density lipoprotein cholesterol concentrations. Sugar-sweetened beverage intake and physical activity levels are each independently associated with insulin resistance-associated metabolic parameters and anthropometric measurements in adolescents. Moreover, low sugar-sweetened beverage intake and high physical activity levels appear to modify each others' effects on several health-related outcome variables.

Influence of oxygen uptake kinetics on physical performance in youth soccer.

PubMed

Doncaster, Greg; Marwood, Simon; Iga, John; Unnithan, Viswanath

2016-09-01

To examine the relationship between oxygen uptake kinetics (VO2 kinetics) and physical measures associated with soccer match play, within a group of highly trained youth soccer players. Seventeen highly trained youth soccer players (age: 13.3 ± 0.4 year, self-assessed Tanner stage: 3 ± 1) volunteered for the study. Players initially completed an incremental treadmill protocol to exhaustion, to establish gaseous exchange threshold (GET) and VO2max (59.1 ± 5.4 mL kg(-1) min(-1)). On subsequent visits, players completed a step transition protocol from rest-moderate-intensity exercise, followed by an immediate transition, and from moderate- to severe-intensity exercise (moderate: 95 % GET, severe: 60 %∆), during which VO2 kinetics were determined. Physical soccer-based performance was assessed using a maximal Yo-Yo intermittent recovery test level 1 (Yo-Yo IR1) and via GPS-derived measures of physical soccer performance during soccer match play, three 2 × 20 min, 11 v 11 matches, to gain measures of physical performance during soccer match play. Partial correlations revealed significant inverse relationships between the unloaded-to-moderate transition time constant (tau) and: Yo-Yo IR1 performance (r = -0.58, P = 0.02) and GPS variables [total distance (TD): r = -0.64, P = 0.007, high-speed running (HSR): r = -0.64, P = 0.008 and high-speed running efforts (HSReff): r = -0.66, P = 0.005]. Measures of VO2 kinetics are related to physical measures associated with soccer match play and could potentially be used to distinguish between those of superior physical performance, within a group of highly trained youth soccer players.

Chapter D. Effects of Urbanization on Stream Ecosystems in the Willamette River Basin and Surrounding Area, Oregon and Washington

USGS Publications Warehouse

Waite, Ian R.; Sobieszczyk, Steven; Carpenter, Kurt D.; Arnsberg, Andrew J.; Johnson, Henry M.; Hughes, Curt A.; Sarantou, Michael J.; Rinella, Frank A.

2008-01-01

This report describes the effects of urbanization on physical, chemical, and biological characteristics of stream ecosystems in 28 watersheds along a gradient of urbanization in the Willamette River basin and surrounding area, Oregon and Washington, from 2003 through 2005. The study that generated the report is one of several urban-effects studies completed nationally by the U.S. Geological Survey National Water-Quality Assessment Program. Watersheds were selected to minimize natural variability caused by factors such as geology, elevation, and climate, and to maximize coverage of different stages of urban development among watersheds. Because land use or population density alone often are not a complete measure of urbanization, a combination of land use, land cover, infrastructure, and socioeconomic variables were integrated into a multimetric urban intensity index (UII) to represent the degree of urban development in each watershed. Physical characteristics studied include stream hydrology, stream temperature, and habitat; chemical characteristics studied include sulfate, chloride, nutrients, pesticides, dissolved and particulate organic and inorganic carbon, and suspended sediment; and biological characteristics studied include algal, macroinvertebrate, and fish assemblages. Semipermeable membrane devices, passive samplers that concentrate trace levels of hydrophobic organic contaminants such as polycyclic aromatic hydrocarbons and polychlorinated biphenyls, also were used. The objectives of the study were to (1) examine physical, chemical, and biological responses along the gradient of urbanization and (2) determine the major physical, chemical, and landscape variables affecting the structure of aquatic communities. Common effects documented in the literature of urbanization on instream physical, chemical, and biological characteristics, such as increased contaminants, increased streamflow flashiness, increased concentrations of chemicals, and changes in aquatic community structure toward a more tolerant community associated with organically enriched conditions, generally were observed in this study. The strongest correlations to the UII and to many of the algal, macroinvertebrate, and fish assemblage metrics and community ordination involved water-chemistry metrics including the total pesticide concentration, toxic equivalents (extract assay from semipermeable membrane devices), and dissolved oxygen. Hydrologic variability metrics, such as flashiness, that normally are considered to be one of the main processes of urban disturbance had a strong association to the algal and fish assemblages in this study; however, the hydrologic variables for macroinvertebrates were secondary to the water-chemistry metrics mentioned above. Generally, the high urban intensity sites had high abundances of eutrophic and lower dissolved oxygen-indicating diatoms, high abundances of noninsects and tolerant insects, and high abundances of nonnative fish species. On the other hand, the low urban intensity sites had higher abundances of pollution sensitive diatoms, larger numbers of the sensitive macroinvertebrate EPT taxa (Ephemeroptera, Plecoptera and Trichoptera Orders), and fish assemblages with higher abundances of sensitive salmonids. The percent salmonid and macroinvertebrate EPT richness metrics plotted against the UII indicated a possible threshold response at about 25 on the UII, which is equivalent to an impervious surface value of about 5 percent. However, due to the added agricultural land use at sites within the 25 to 60 UII range, this possible threshold probably is not solely due to urbanization, but a combination of urban and agricultural land use. The effects of agricultural and urban land use could not be distinguished from each other, yet combined they provide a good assessment of overall watershed disturbance.

Variability and Stability in Daily Moderate-to-Vigorous Physical Activity among 10 Year Old Children

PubMed Central

Pereira, Sara; Gomes, Thayse Natacha; Borges, Alessandra; Santos, Daniel; Souza, Michele; dos Santos, Fernanda K.; Chaves, Raquel N.; Katzmarzyk, Peter T.; Maia, José A. R.

2015-01-01

Day-to-day variability and stability of children’s physical activity levels across days of the week are not well understood. Our aims were to examine the day-to-day variability of moderate-to-vigorous physical activity (MVPA), to determine factors influencing the day-to-day variability of MVPA and to estimate stability of MVPA in children. The sample comprises 686 Portuguese children (10 years of age). MVPA was assessed with an accelerometer, and BMI was computed from measured height and weight. Daily changes in MVPA and their correlates (gender, BMI, and maturity) were modeled with a multilevel approach, and tracking was calculated using Foulkes & Davies γ. A total of 51.3% of boys and 26.2% of girls achieved 60 min/day of MVPA on average. Daily MVPA was lower during the weekend (23.6% of boys and 13.6% of girls comply with the recommended 60 min/day of MVPA) compared to weekdays (60.8% and 35.4%, boys and girls, respectively). Normal weight children were more active than obese children and no effect was found for biological maturation. Tracking is low in both boys (γ = 0.59 ± 0.01) and girls (γ = 0.56 ± 0.01). Children’s MVPA levels during a week are highly unstable. In summary, boys are more active than girls, maturation does not affect their MVPA, and obese children are less likely to meet 60 min/day of MVPA. These results highlight the importance of providing opportunities for increasing children’s daily MVPA on all days of week, especially on the weekend. PMID:26262632

Variability and Stability in Daily Moderate-to-Vigorous Physical Activity among 10 Year Old Children.

PubMed

Pereira, Sara; Gomes, Thayse Natacha; Borges, Alessandra; Santos, Daniel; Souza, Michele; dos Santos, Fernanda K; Chaves, Raquel N; Katzmarzyk, Peter T; Maia, José A R

2015-08-07

Day-to-day variability and stability of children's physical activity levels across days of the week are not well understood. Our aims were to examine the day-to-day variability of moderate-to-vigorous physical activity (MVPA), to determine factors influencing the day-to-day variability of MVPA and to estimate stability of MVPA in children. The sample comprises 686 Portuguese children (10 years of age). MVPA was assessed with an accelerometer, and BMI was computed from measured height and weight. Daily changes in MVPA and their correlates (gender, BMI, and maturity) were modeled with a multilevel approach, and tracking was calculated using Foulkes &amp; Davies γ. A total of 51.3% of boys and 26.2% of girls achieved 60 min/day of MVPA on average. Daily MVPA was lower during the weekend (23.6% of boys and 13.6% of girls comply with the recommended 60 min/day of MVPA) compared to weekdays (60.8% and 35.4%, boys and girls, respectively). Normal weight children were more active than obese children and no effect was found for biological maturation. Tracking is low in both boys (γ = 0.59 ± 0.01) and girls (γ = 0.56 ± 0.01). Children's MVPA levels during a week are highly unstable. In summary, boys are more active than girls, maturation does not affect their MVPA, and obese children are less likely to meet 60 min/day of MVPA. These results highlight the importance of providing opportunities for increasing children's daily MVPA on all days of week, especially on the weekend.

Physical Activity of Malaysian Primary School Children: Comparison by Sociodemographic Variables and Activity Domains.

PubMed

Wong, Jyh Eiin; Parikh, Panam; Poh, Bee Koon; Deurenberg, Paul

2016-07-01

This study describes the physical activity of primary school children according to sociodemographic characteristics and activity domains. Using the Malaysian South East Asian Nutrition Surveys data, 1702 children aged 7 to 12 years were included in the analysis. Physical activity was reported as a total score and categorized into low, medium, and high levels based on Physical Activity Questionnaire for Older Children. Higher overall activity scores were found in boys, younger age, non-Chinese ethnicity, and normal body mass index category. Sex, age, and ethnicity differences were found in structured or organized, physical education, and outside-of-school domain scores. Transport-related scores differed by age group, ethnicity, household income, and residential areas but not among the three physical activity levels. Participation of girls, Chinese, and older children were low in overall and almost all activity domains. Sociodemographic characteristics are important factors to consider in increasing the different domains of physical activity among Malaysian children. © 2016 APJPH.

Physical Activity and Blood Lead Concentration in Korea: Study Using the Korea National Health and Nutrition Examination Survey (2008-2013).

PubMed

Rhie, Jeongbae; Lee, Hye-Eun

2016-06-01

Physical activity normally has a positive influence on health, however it can be detrimental in the presence of air pollution. Lead, a heavy metal with established adverse health effects, is a major air pollutant. We evaluated the correlation between blood lead concentration and physical activity using data collected from the Korea National Health and Nutrition Examination Survey. Multivariate logistic regression analysis was performed after dividing participants according to whether they were in the top 25% in the distribution of blood lead concentration (i.e., ≥ 2.76 µg/dL), with physical activity level as an independent variable and adjusting for factors such as age, sex, drinking, smoking, body mass index, region, and occupation. The high physical activity group had greater odds of having a blood lead concentration higher than 2.76 µg/dL (odds ratio 1.29, 95% CI 1.11-1.51) compared to the low physical activity group. Furthermore, blood lead concentration is correlated with increasing physical activity.

Meta-analysis of workplace physical activity interventions.

PubMed

Conn, Vicki S; Hafdahl, Adam R; Cooper, Pamela S; Brown, Lori M; Lusk, Sally L

2009-10-01

Most adults do not achieve adequate physical activity levels. Despite the potential benefits of worksite health promotion, no previous comprehensive meta-analysis has summarized health and physical activity behavior outcomes from such programs. This comprehensive meta-analysis integrated the extant wide range of worksite physical activity intervention research. Extensive searching located published and unpublished intervention studies reported from 1969 through 2007. Results were coded from primary studies. Random-effects meta-analytic procedures, including moderator analyses, were completed in 2008. Effects on most variables were substantially heterogeneous because diverse studies were included. Standardized mean difference (d) effect sizes were synthesized across approximately 38,231 subjects. Significantly positive effects were observed for physical activity behavior (0.21); fitness (0.57); lipids (0.13); anthropometric measures (0.08); work attendance (0.19); and job stress (0.33). The significant effect size for diabetes risk (0.98) is less robust given small sample sizes. The mean effect size for fitness corresponds to a difference between treatment minus control subjects' means on VO2max of 3.5 mL/kg/min; for lipids, -0.2 on the ratio of total cholesterol to high-density lipoprotein; and for diabetes risk, -12.6 mg/dL on fasting glucose. These findings document that some workplace physical activity interventions can improve both health and important worksite outcomes. Effects were variable for most outcomes, reflecting the diversity of primary studies. Future primary research should compare interventions to confirm causal relationships and further explore heterogeneity.

Stochastic goal-oriented error estimation with memory

NASA Astrophysics Data System (ADS)

Ackmann, Jan; Marotzke, Jochem; Korn, Peter

2017-11-01

We propose a stochastic dual-weighted error estimator for the viscous shallow-water equation with boundaries. For this purpose, previous work on memory-less stochastic dual-weighted error estimation is extended by incorporating memory effects. The memory is introduced by describing the local truncation error as a sum of time-correlated random variables. The random variables itself represent the temporal fluctuations in local truncation errors and are estimated from high-resolution information at near-initial times. The resulting error estimator is evaluated experimentally in two classical ocean-type experiments, the Munk gyre and the flow around an island. In these experiments, the stochastic process is adapted locally to the respective dynamical flow regime. Our stochastic dual-weighted error estimator is shown to provide meaningful error bounds for a range of physically relevant goals. We prove, as well as show numerically, that our approach can be interpreted as a linearized stochastic-physics ensemble.

Should we trust build-up/wash-off water quality models at the scale of urban catchments?

PubMed

Bonhomme, Céline; Petrucci, Guido

2017-01-01

Models of runoff water quality at the scale of an urban catchment usually rely on build-up/wash-off formulations obtained through small-scale experiments. Often, the physical interpretation of the model parameters, valid at the small-scale, is transposed to large-scale applications. Testing different levels of spatial variability, the parameter distributions of a water quality model are obtained in this paper through a Monte Carlo Markov Chain algorithm and analyzed. The simulated variable is the total suspended solid concentration at the outlet of a periurban catchment in the Paris region (2.3 km 2 ), for which high-frequency turbidity measurements are available. This application suggests that build-up/wash-off models applied at the catchment-scale do not maintain their physical meaning, but should be considered as "black-box" models. Copyright © 2016 Elsevier Ltd. All rights reserved.

Standards for Environmental Measurement Using GIS: Toward a Protocol for Protocols.

PubMed

Forsyth, Ann; Schmitz, Kathryn H; Oakes, Michael; Zimmerman, Jason; Koepp, Joel

2006-02-01

Interdisciplinary research regarding how the built environment influences physical activity has recently increased. Many research projects conducted jointly by public health and environmental design professionals are using geographic information systems (GIS) to objectively measure the built environment. Numerous methodological issues remain, however, and environmental measurements have not been well documented with accepted, common definitions of valid, reliable variables. This paper proposes how to create and document standardized definitions for measures of environmental variables using GIS with the ultimate goal of developing reliable, valid measures. Inherent problems with software and data that hamper environmental measurement can be offset by protocols combining clear conceptual bases with detailed measurement instructions. Examples demonstrate how protocols can more clearly translate concepts into specific measurement. This paper provides a model for developing protocols to allow high quality comparative research on relationships between the environment and physical activity and other outcomes of public health interest.

Demographic, clinical, and quality of life variables related to embarrassment in veterans living with an intestinal stoma.

PubMed

Mitchell, Kimberly A; Rawl, Susan M; Schmidt, C Max; Grant, Marcia; Ko, Clifford Y; Baldwin, Carol M; Wendel, Christopher; Krouse, Robert S

2007-01-01

The study aims were to identify demographic, clinical, and quality of life variables related to embarrassment for people living with ostomies and to determine the experiences and/or feelings of veterans who were embarrassed by their ostomy. This was a cross-sectional, correlational study. A convenience sample of veterans (n = 239) living with ostomies from 3 VA medical centers was studied. The veterans were primarily Caucasian (84%), male (92%), and older (M = 69). The modified City of Hope Quality of Life-Ostomy questionnaire was used. Additionally, an open-ended question related to living with an ostomy was asked. The questionnaire packets were mailed to participants and self-administered. Approximately half of the participants (48%) rated their embarrassment as low, but 26% reported high embarrassment. Participants with high embarrassment were compared to those with low embarrassment on demographic, clinical, and quality of life variables. High embarrassment was associated with poorer total quality of life (P < .001) and poorer quality of life on the physical (P < .001), psychological (P < .001), social (P < .001), and spiritual (P < .001) subscales. Younger (P < .001) and unpartnered veterans (P < .001) were more likely to be highly embarrassed. Veterans with high embarrassment had higher anxiety (P < .001) and depression (P < .001), more difficulty with intimacy (P < .001), and felt more isolated (P < .001). Spiritual domain variables like hopefulness were associated with low embarrassment (P < .001). Sources of embarrassment included leakage, odor, and noise. Embarrassment may negatively impact a person's quality of life; therefore, the variables associated with high embarrassment should be recognized and addressed.

Improving Exercise Adherence and Physical Measures in English-Speaking Latina Women.

PubMed

Martin, Lorena; Signorile, Joseph F; Kahn, Barbara E; Perkins, Andrew W; Ahn, Soyeon; Perry, Arlette C

2015-12-01

Epidemiological data have established that lack of physical activity increases risk factors for chronic diseases. Data also suggests that physical activity participation is lowest in minority women, particularly Latinas, and that the nature of the exercise and attitudes toward exercise may influence exercise adherence. The purpose of this study was to determine the effect of hypertrophy training (HT) or power training (PT) used concomitantly with evaluative conditioning (EC) or neutral conditioning (NC) on exercise adherence as well as in physical and psychosocial variables in Latina women. EC is a behavioral method using paired stimuli to develop and strengthen new associations in memory. Two hundred thirty-one English-speaking Latina women (mean ± SD, age 36.8 ± 15.9 years) were randomly assigned to standard HT or high-speed circuit PT and then further stratified to receive EC or NC. One hundred forty-two Latina women completed pre- and posttesting. For HT, EC produced significantly greater exercise time across the training period than NC. HT and PT both significantly improved all physical, functional, and psychosocial variables, with exception of leg extension and usual gait speed (p < 0.05). EC can positively impact exercise adherence during HT in Latina women; while body composition, neuromuscular, and functional performances can be increased using HT and PT independent of psychological conditioning.

Aircraft Conceptual Design and Risk Analysis Using Physics-Based Noise Prediction

NASA Technical Reports Server (NTRS)

Olson, Erik D.; Mavris, Dimitri N.

2006-01-01

An approach was developed which allows for design studies of commercial aircraft using physics-based noise analysis methods while retaining the ability to perform the rapid trade-off and risk analysis studies needed at the conceptual design stage. A prototype integrated analysis process was created for computing the total aircraft EPNL at the Federal Aviation Regulations Part 36 certification measurement locations using physics-based methods for fan rotor-stator interaction tones and jet mixing noise. The methodology was then used in combination with design of experiments to create response surface equations (RSEs) for the engine and aircraft performance metrics, geometric constraints and take-off and landing noise levels. In addition, Monte Carlo analysis was used to assess the expected variability of the metrics under the influence of uncertainty, and to determine how the variability is affected by the choice of engine cycle. Finally, the RSEs were used to conduct a series of proof-of-concept conceptual-level design studies demonstrating the utility of the approach. The study found that a key advantage to using physics-based analysis during conceptual design lies in the ability to assess the benefits of new technologies as a function of the design to which they are applied. The greatest difficulty in implementing physics-based analysis proved to be the generation of design geometry at a sufficient level of detail for high-fidelity analysis.

Response to elevated CO2 in the temperate C3 grass Festuca arundinaceae across a wide range of soils

PubMed Central

Nord, Eric A.; Jaramillo, Raúl E.; Lynch, Jonathan P.

2015-01-01

Soils vary widely in mineral nutrient availability and physical characteristics, but the influence of this variability on plant responses to elevated CO2 remains poorly understood. As a first approximation of the effect of global soil variability on plant growth response to CO2, we evaluated the effect of CO2 on tall fescue (Festuca arundinacea) grown in soils representing 10 of the 12 global soil orders plus a high-fertility control. Plants were grown in small pots in continuously stirred reactor tanks in a greenhouse. Elevated CO2 (800 ppm) increased plant biomass in the high-fertility control and in two of the more fertile soils. Elevated CO2 had variable effects on foliar mineral concentration—nitrogen was not altered by elevated CO2, and phosphorus and potassium were only affected by CO2 in a small number of soils. While leaf photosynthesis was stimulated by elevated CO2 in six soils, canopy photosynthesis was not stimulated. Four principle components were identified; the first was associated with foliar minerals and soil clay, and the second with soil acidity and foliar manganese concentration. The third principle component was associated with gas exchange, and the fourth with plant biomass and soil minerals. Soils in which tall fescue did not respond to elevated CO2 account for 83% of global land area. These results show that variation in soil physical and chemical properties have important implications for plant responses to global change, and highlight the need to consider soil variability in models of vegetation response to global change. PMID:25774160

Understanding the recent changes in the Southern Ocean carbon cycle: A multidisciplinary approach

NASA Astrophysics Data System (ADS)

Manizza, M.; Kahru, M.; Menemenlis, D.; Nevison, C. D.; Mitchell, B. G.; Keeling, R. F.

2016-12-01

The Southern Ocean represents a key area of the global ocean for the uptake of the CO2 originating from fossil fuels emissions. In these waters, cold temperatures combined with high rates of biological production drive the carbon uptake that accounts for about one-third of the global ocean uptake.Recent studies showed that changes in the Southern Annular Mode (SAM) index, mainly a proxy of the intensity of westerly winds, had a significant impact on the temporal variability of the CO2 uptake in the Southern Ocean. In order to shed light on this problem we propose to use both satellite-derived estimates of ocean productivity and carbon export in combinations of ocean physical and biogeochemical state estimates focusing on the 2006-2013 period. While the estimates of carbon fixation and export based on remote sensing will provide key information on the spatial and temporal variations of the biological carbon pump, the ocean state estimates will provide additional information on physical and carbon cycle processes, including the air-sea CO2 fluxes of the Southern Ocean in the 2006-2013 period where model solutions have been optimized.These physical estimates will be used to force an ocean biogeochemical model (ECCO2-Darwin) that will compute the CO2 uptake for each year. The physical model, forced with optimized atmospheric forcing, aims to realistically simulate interannual ocean climate variability that drives changes in both physical and biogeochemical processes ultimately impacting the carbon uptake of the Southern Ocean, and potentially responding to the SAM index variations.Although in this study great emphasis is given to the role of physical climate variations at driving the CO2 uptake of these polar waters, we will integrate model results with estimates from remote sensing techniques to better understand role of the biological carbon pump and its variability potentially responding to the SAM index changes.

Connecting health-related quality of life and mental health in dementia caregivers from Colombia, South America.

PubMed

Perrin, Paul B; Morgan, Matthew; Aretouli, Eleni; Sutter, Megan; Snipes, Daniel J; Hoyos, Guillermo Ramirez; Buraye, Jacqueline Arabia; Arango-Lasprilla, Juan Carlos

2014-01-01

Research in Caucasian populations has begun to examine the broad associations between physical and mental health in dementia caregivers. However, the examination of this relationship in Latin America is largely absent from the literature despite the fact that the region will see a major increase in dementia cases over the next 20 years. The current study examined the associations between health-related quality of life (HRQOL) and mental health in 90 dementia caregivers from Colombia, South America. A canonical correlation found that higher caregiver HRQOL was related to better mental health, as expected. Caregivers with high vitality and low role limitations due to physical problems tended to have low depression and high satisfaction with life. Follow-up multiple regressions found that caregiver role limitations due to physical problems was uniquely associated with satisfaction with life, whereas vitality, role limitations due to physical problems, and pain were uniquely associated with burden (although the pain effect was likely error due to a suppressor effect). Additionally, vitality and social functioning were uniquely negatively related to depression. Because of the extremely high overlap between these two sets of variables, dementia interventions are needed in Latin America that target both caregiver mental and physical health, as both likely operate in unison and influence each other.

Students' tripartite efficacy beliefs in high school physical education: within- and cross-domain relations with motivational processes and leisure-time physical activity.

PubMed

Jackson, Ben; Whipp, Peter R; Chua, K L Peter; Dimmock, James A; Hagger, Martin S

2013-02-01

Within instructional settings, individuals form relational efficacy appraisals that complement their self-efficacy beliefs. In high school physical education (PE), for instance, students develop a level of confidence in their teacher's capabilities, as well as estimating how confident they think their teacher is in their (i.e., the students') ability. Grounded in existing transcontextual work, we examined the motivational pathways through which students' relational efficacy and self-efficacy beliefs in PE were predictive of their leisure-time physical activity. Singaporean students (N = 990; age M = 13.95, SD = 1.02) completed instruments assessing efficacy beliefs, perceptions of teacher relatedness support, and autonomous motivation toward PE, and 2 weeks later they reported their motivation toward, and engagement in, leisure-time physical activity. Structural equation modeling revealed that students reported stronger other-efficacy and RISE beliefs when they felt that their teacher created a highly relatedness-supportive environment. In turn, their relational efficacy beliefs (a) supported their confidence in their own ability, (b) directly and indirectly predicted more autonomous motives for participation in PE, and (c) displayed prospective transcontextual effects in relation to leisure-time variables. By emphasizing the adaptive motivational effects associated with the tripartite constructs, these findings highlight novel pathways linking students' efficacy perceptions with leisure-time outcomes.

Predicting Forearm Physical Exposures During Computer Work Using Self-Reports, Software-Recorded Computer Usage Patterns, and Anthropometric and Workstation Measurements.

PubMed

Huysmans, Maaike A; Eijckelhof, Belinda H W; Garza, Jennifer L Bruno; Coenen, Pieter; Blatter, Birgitte M; Johnson, Peter W; van Dieën, Jaap H; van der Beek, Allard J; Dennerlein, Jack T

2017-12-15

Alternative techniques to assess physical exposures, such as prediction models, could facilitate more efficient epidemiological assessments in future large cohort studies examining physical exposures in relation to work-related musculoskeletal symptoms. The aim of this study was to evaluate two types of models that predict arm-wrist-hand physical exposures (i.e. muscle activity, wrist postures and kinematics, and keyboard and mouse forces) during computer use, which only differed with respect to the candidate predicting variables; (i) a full set of predicting variables, including self-reported factors, software-recorded computer usage patterns, and worksite measurements of anthropometrics and workstation set-up (full models); and (ii) a practical set of predicting variables, only including the self-reported factors and software-recorded computer usage patterns, that are relatively easy to assess (practical models). Prediction models were build using data from a field study among 117 office workers who were symptom-free at the time of measurement. Arm-wrist-hand physical exposures were measured for approximately two hours while workers performed their own computer work. Each worker's anthropometry and workstation set-up were measured by an experimenter, computer usage patterns were recorded using software and self-reported factors (including individual factors, job characteristics, computer work behaviours, psychosocial factors, workstation set-up characteristics, and leisure-time activities) were collected by an online questionnaire. We determined the predictive quality of the models in terms of R2 and root mean squared (RMS) values and exposure classification agreement to low-, medium-, and high-exposure categories (in the practical model only). The full models had R2 values that ranged from 0.16 to 0.80, whereas for the practical models values ranged from 0.05 to 0.43. Interquartile ranges were not that different for the two models, indicating that only for some physical exposures the full models performed better. Relative RMS errors ranged between 5% and 19% for the full models, and between 10% and 19% for the practical model. When the predicted physical exposures were classified into low, medium, and high, classification agreement ranged from 26% to 71%. The full prediction models, based on self-reported factors, software-recorded computer usage patterns, and additional measurements of anthropometrics and workstation set-up, show a better predictive quality as compared to the practical models based on self-reported factors and recorded computer usage patterns only. However, predictive quality varied largely across different arm-wrist-hand exposure parameters. Future exploration of the relation between predicted physical exposure and symptoms is therefore only recommended for physical exposures that can be reasonably well predicted. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Maternal Factors Predicting Cognitive and Behavioral Characteristics of Children with Fetal Alcohol Spectrum Disorders

PubMed Central

May, Philip A.; Tabachnick, Barbara G.; Gossage, J. Phillip; Kalberg, Wendy O.; Marais, Anna-Susan; Robinson, Luther K.; Manning, Melanie A.; Blankenship, Jason; Buckley, David; Hoyme, H. Eugene; Adnams, Colleen M.

2013-01-01

Objective To provide an analysis of multiple predictors of cognitive and behavioral traits for children with fetal alcohol spectrum disorders (FASD). Method Multivariate correlation techniques were employed with maternal and child data from epidemiologic studies in a community in South Africa. Data on 561 first grade children with fetal alcohol syndrome (FAS), partial FAS (PFAS), and not FASD and their mothers were analyzed by grouping 19 maternal variables into categories (physical, demographic, childbearing, and drinking) and employed in structural equation models (SEM) to assess correlates of child intelligence (verbal and non-verbal) and behavior. Results A first SEM utilizing only seven maternal alcohol use variables to predict cognitive/behavioral traits was statistically significant (B = 3.10, p < .05), but explained only 17.3% of the variance. The second model incorporated multiple maternal variables and was statistically significant explaining 55.3% of the variance. Significantly correlated with low intelligence and problem behavior were demographic (B = 3.83, p < .05) (low maternal education, low socioeconomic status (SES), and rural residence) and maternal physical characteristics (B = 2.70, p < .05) (short stature, small head circumference, and low weight). Childbearing history and alcohol use composites were not statistically significant in the final complex model, and were overpowered by SES and maternal physical traits. Conclusions While other analytic techniques have amply demonstrated the negative effects of maternal drinking on intelligence and behavior, this highly-controlled analysis of multiple maternal influences reveals that maternal demographics and physical traits make a significant enabling or disabling contribution to child functioning in FASD. PMID:23751886

Does the Madden-Julian Oscillation influence aerosol variability?

NASA Astrophysics Data System (ADS)

Tian, Baijun; Waliser, Duane E.; Kahn, Ralph A.; Li, Qinbin; Yung, Yuk L.; Tyranowski, Tomasz; Geogdzhayev, Igor V.; Mishchenko, Michael I.; Torres, Omar; Smirnov, Alexander

2008-06-01

We investigate the modulation of aerosols by the Madden-Julian Oscillation (MJO) using multiple, global satellite aerosol products: aerosol index (AI) from the Total Ozone Mapping Spectrometer (TOMS) on Nimbus-7, and aerosol optical thickness (AOT) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua and the Advanced Very High Resolution Radiometer (AVHRR) on NOAA satellites. A composite MJO analysis indicates that large variations in the TOMS AI and MODIS/AVHRR AOT are found over the equatorial Indian and western Pacific Oceans where MJO convection is active, as well as the tropical Africa and Atlantic Ocean where MJO convection is weak but the background aerosol level is high. A strong inverse linear relationship between the TOMS AI and rainfall anomalies, but a weaker, less coherent positive correlation between the MODIS/AVHRR AOT and rainfall anomalies, were found. The MODIS/AVHRR pattern is consistent with ground-based Aerosol Robotic Network data. These results indicate that the MJO and its associated cloudiness, rainfall, and circulation variability systematically influence the variability in remote sensing aerosol retrieval results. Several physical and retrieval algorithmic factors that may contribute to the observed aerosol-rainfall relationships are discussed. Preliminary analysis indicates that cloud contamination in the aerosol retrievals is likely to be a major contributor to the observed relationships, although we cannot exclude possible contributions from other physical mechanisms. Future research is needed to fully understand these complex aerosol-rainfall relationships.

Comparing demographic, health status and psychosocial strategies of audience segmentation to promote physical activity.

PubMed

Boslaugh, Sarah E; Kreuter, Matthew W; Nicholson, Robert A; Naleid, Kimberly

2005-08-01

The goal of audience segmentation is to identify population subgroups that are homogeneous with respect to certain variables associated with a given outcome or behavior. When such groups are identified and understood, targeted intervention strategies can be developed to address their unique characteristics and needs. This study compares the results of audience segmentation for physical activity that is based on either demographic, health status or psychosocial variables alone, or a combination of all three types of variables. Participants were 1090 African-American and White adults from two public health centers in St Louis, MO. Using a classification-tree algorithm to form homogeneous groups, analyses showed that more segments with greater variability in physical activity were created using psychosocial versus health status or demographic variables and that a combination of the three outperformed any individual set of variables. Simple segmentation strategies such as those relying on demographic variables alone provided little improvement over no segmentation at all. Audience segmentation appears to yield more homogeneous subgroups when psychosocial and health status factors are combined with demographic variables.

Sensitivity of monthly heart rate and psychometric measures for monitoring physical performance in highly trained young handball players.

PubMed

Buchheit, M

2015-05-01

The aim of the present study was to examine whether monthly resting heart rate (HR), HR variability (HRV) and psychometric measures can be used to monitor changes in physical performance in highly-trained adolescent handball players. Data were collected in 37 adolescent players (training 10±2.1 h.wk(-1)) on 11 occasions from September to May during the in-season period, and included an estimation of training status (resting HR and HRV, the profile of mood state (POMS) questionnaire), and 3 physical performance tests (a 10-m sprint, a counter movement jump and a graded aerobic intermittent test, 30-15 Intermittent Fitness Test). The sensitivity of HR and psychometric measures to changes in physical performance was poor (< 20%), irrespective of the training status markers and the performance measures. The specificity was however strong (> 75%), irrespective of the markers and the performance measures. Finally, the difference in physical performance between players with better vs. worse estimated training status were all almost certainly trivial. The present results highlight the limitation of monthly measures of resting HR, HRV and perceived mood and fatigue for predicting in-season changes in physical performance in highly-trained adolescent handball players. This suggests that more frequent monitoring might be required, and/or that other markers might need to be considered. © Georg Thieme Verlag KG Stuttgart · New York.

Neighborhood walkability, income, and hour-by-hour physical activity patterns.

PubMed

Arvidsson, Daniel; Eriksson, Ulf; Lönn, Sara Larsson; Sundquist, Kristina

2013-04-01

This study aimed to investigate both the mean daily physical activity and the hour-by-hour physical activity patterns across the day using accelerometry and how they are associated with neighborhood walkability and individual income. Moderate physical activity (MPA) was assessed by accelerometry in 2252 adults in the city of Stockholm, Sweden. Neighborhood walkability (residential density, street connectivity, and land use mix) was objectively assessed within 1000m network buffers around the participants' residence and individual income was self-reported. Living in a high walkability neighborhood was associated with more mean daily MPA compared with living in a low walkability neighborhood on weekdays and weekend days. Hour-by-hour analyses showed that this association appeared mainly in the afternoon/early evening during weekdays, whereas it appeared across the middle of the day during weekend days. Individual income was associated with mean daily MPA on weekend days. On weekdays, the hour-by-hour analyses showed that high income was associated with more MPA around noon and in late afternoon/early evening, whereas low income was associated with more MPA at the hours before noon and in the early afternoon. During the weekend, high income was more consistently associated with higher MPA. Hour-by-hour accelerometry physical activity patterns provides a more comprehensive picture of the associations between neighborhood walkability and individual income and physical activity and the variability of these associations across the day.

Tailored cognitive-behavioural therapy and exercise training improves the physical fitness of patients with fibromyalgia.

PubMed

van Koulil, S; van Lankveld, W; Kraaimaat, F W; van Helmond, T; Vedder, A; van Hoorn, H; Donders, A R T; Wirken, L; Cats, H; van Riel, P L C M; Evers, A W M

2011-12-01

Patients with fibromyalgia have diminished levels of physical fitness, which may lead to functional disability and exacerbating complaints. Multidisciplinary treatment comprising cognitive-behavioural therapy (CBT) and exercise training has been shown to be effective in improving physical fitness. However, due to the high drop-out rates and large variability in patients' functioning, it was proposed that a tailored treatment approach might yield more promising treatment outcomes. High-risk fibromyalgia patients were randomly assigned to a waiting list control group (WLC) or a treatment condition (TC), with the treatment consisting of 16 twice-weekly sessions of CBT and exercise training tailored to the patient's cognitive-behavioural pattern. Physical fitness was assessed with two physical tests before and 3 months after treatment and at corresponding intervals in the WLC. Treatment effects were evaluated using linear mixed models. The level of physical fitness had improved significantly in the TC compared with the WLC. Attrition rates were low, effect sizes large and reliable change indices indicated a clinically relevant improvement among the TC. A tailored multidisciplinary treatment approach for fibromyalgia consisting of CBT and exercise training is well tolerated, yields clinically relevant changes, and appears a promising approach to improve patients' physical fitness. ClinicalTrials.gov ID NCT00268606.

Level and potential social-ecological factors associated with physical inactivity and sedentary behavior among Moroccan school-age adolescents: a cross-sectional study.

PubMed

El-Ammari, Abdelghaffar; El Kazdouh, Hicham; Bouftini, Siham; El Fakir, Samira; El Achhab, Youness

2017-05-18

Creating a successful intervention that supports an active lifestyle and prevents sedentary one requires a better understanding of the factors associated with physical inactivity (PI) and sedentary behavior (SB). However, these factors have not been assessed among Moroccan adolescents. This study aimed to determine prevalence of PI and SB and to explore their potential social-ecological associated factors in school-age adolescents. In this cross-sectional study, 764 students (age range, 14-19 years) were enrolled from six schools in Taza city, Morocco. The Global School-based Student Health Survey was used to collect data about variables. We used bivariate and multivariate analyses to assess relations between dependent and independent variables. Overall, the prevalence of PI was 79.5% and SB was 36.5%. Among girls, these rates were higher (87.0 and 39.1%, respectively) than rates shown in boys (70.9 and 33.6%, respectively). In the multivariate logistic regression analysis, PI was associated with the following variables: illiterate father, hunger, suicidal ideation, inadequate vegetable consumption, and absence from physical education classes. Age, inadequate vegetable consumption, and absenteeism were associated with SB. The prevalence of PI and SB is high, especially among girls. Thus, there is an urgent need to implement appropriate interventions to reduce PI and SB levels in secondary school-age adolescents and the associated factors identified can be useful.

Lifetime trauma victimization and PTSD in relation to psychopathy and antisocial personality disorder in a sample of incarcerated women and men.

PubMed

Gobin, Robyn L; Reddy, Madhavi K; Zlotnick, Caron; Johnson, Jennifer E

2015-01-01

Antisocial personality disorder (ASPD) and psychopathy are similar, but distinct, psychiatric conditions that are common in male and female inmates; a segment of the population with high rates of trauma exposure. It is unclear whether specific types of lifetime trauma are associated with ASPD and psychopathy in incarcerated women and men. Furthermore, the unique roles of post-traumatic stress disorder (PTSD) symptom severity and trauma victimization in antisocial personality disturbance are not well-understood. The paper aims to discuss these issues. This study investigated associations between trauma variables (different kinds of traumatic experiences and PTSD) and antisocial personality variables (ASPD and psychopathy) in a sample of incarcerated women and men who participated in a randomized clinical trial for major depressive disorder. In total, 88 incarcerated men and women were assessed for ASPD diagnosis, psychopathy severity, PTSD symptom severity, and history of physical, sexual, and crime-related trauma. Regression analyses predicted ASPD or psychopathy from trauma variables, controlling for gender. Physical trauma was the only form of trauma that was significantly related to psychopathy. Physical trauma and crime-related trauma were associated with ASPD. PTSD symptom severity was not associated with psychopathy or ASPD. There are associations between some kinds of lifetime trauma exposure and current ASPD/psychopathy in the target sample, but these associations do not appear to be mediated through current PTSD symptoms.

Intercontinental convergence of stream fish community traits along geomorphic and hydraulic gradients

USGS Publications Warehouse

Lamouroux, N.; Poff, N.L.; Angermeier, P.L.

2002-01-01

Community convergence across biogeographically distinct regions suggests the existence of key, repeated, evolutionary mechanisms relating community characteristics to the environment. However, convergence studies at the community level often involve only qualitative comparisons of the environment and may fail to identify which environmental variables drive community structure. We tested the hypothesis that the biological traits of fish communities on two continents (Europe and North America) are similarly related to environmental conditions. Specifically, from observations of individual fish made at the microhabitat scale (a few square meters) within French streams, we generated habitat preference models linking traits of fish species to local scale hydraulic conditions (Froude number), Using this information, we then predicted how hydraulics and geomorphology at the larger scale of stream reaches (several pool-riffle sequences) should quantitatively influence the trait composition of fish communities. Trait composition for fishes in stream reaches with low Froude number at low flow or high proportion of pools was predicted as nonbenthic, large, fecund, long-lived, nonstreamlined, and weak swimmers. We tested our predictions in contrasting stream reaches in France (n = 11) and Virginia, USA (n = 76), using analyses of covariance to quantify the relative influence of continent vs. physical habitat variables on fish traits. The reach-scale convergence analysis indicated that trait proportions in the communities differed between continents (up to 55% of the variance in each trait was explained by "continent"), partly due to distinct evolutionary histories. However, within continents, trait proportions were comparably related to the hydraulic and geomorphic variables (up to 54% of the variance within continents explained). In particular, a synthetic measure of fish traits in reaches was well explained (50% of its variance) by the Froude number independently of the continent. The effect of physical variables did not differ across continents for most traits, confirming our predictions qualitatively and quantitatively. Therefore, despite phylogenetic and historical differences between continents, fish communities of France and Virginia exhibit convergence in biological traits related to hydraulics and geomorphology. This convergence reflects morphological and behavioral adaptations to physical stress in streams. This study supports the existence of a habitat template for ecological strategies. Some key quantitative variables that define this habitat template can be identified by characterizing how individual organisms use their physical environment, and by using dimensionless physical variables that reveal common energetic properties in different systems. Overall, quantitative tests of community convergence are efficient tools to demonstrate that some community traits are predictable from environmental features.

The Self-Presentation Motives for Physical Activity Questionnaire: Instrument Development and Preliminary Construct Validity Evidence.

PubMed

Howle, Timothy C; Dimmock, James A; Whipp, Peter R; Jackson, Ben

2015-06-01

With the aim of advancing the literature on impression management in physical activity settings, we developed a theoretically derived 2 by 2 instrument that was designed to measure different types of context-specific self-presentation motives. Following item generation and expert review (Study 1), the instrument was completed by 206 group exercise class attendees (Study 2) and 463 high school physical education students (Study 3). Our analyses supported the intended factor structure (i.e., reflecting acquisitive-agentic, acquisitive-communal, protective-agentic, and protective-communal motives). We found some support for construct validity, and the self-presentation motives were associated with variables of theoretical and applied interest (e.g., impression motivation and construction, social anxiety, social and achievement goals, efficacy beliefs, engagement). Taken together, the results indicate that the Self-presentation Motives for Physical Activity Questionnaire (SMPAQ) may be useful for measuring various types of self-presentation motives in physical activity settings.

Rethinking Hospital-Associated Deconditioning: Proposed Paradigm Shift

PubMed Central

Mangione, Kathleen K.; Stevens-Lapsley, Jennifer E.

2015-01-01

Physical therapists often treat older adults with marked deficits in physical function secondary to an acute hospitalization. These deficits are often collectively defined as hospital-associated deconditioning (HAD). However, there is a paucity of evidence that objectively demonstrates the efficacy of physical therapy for older adults with HAD. Older adults with HAD represent a highly variable and complex population and thus may be difficult to study and develop effective interventions for using our current rehabilitation strategies. This perspective article outlines an innovative framework to operationalize and treat older adults with HAD. This framework may help therapists apply emerging exercise strategies to this population and facilitate additional research to support the total value of physical therapy for older adults in postacute care settings—with value measured not only by improvements in physical performance but perhaps also by reduced rates of disability development, rehospitalization, and institutionalization. PMID:25908526

Can basin land use effects on physical characteristics of streams be determined at broad geographic scales?

USGS Publications Warehouse

Goldstein, R.M.; Carlisle, D.M.; Meador, M.R.; Short, T.M.

2007-01-01

The environmental setting (e.g., climate, topography, geology) and land use affect stream physical characteristics singly and cumulatively. At broad geographic scales, we determined the importance of environmental setting and land use in explaining variation in stream physical characteristics. We hypothesized that as the spatial scale decreased from national to regional, land use would explain more of the variation in stream physical characteristics because environmental settings become more homogeneous. At a national scale, stepwise linear regression indicated that environmental setting was more important in explaining variability in stream physical characteristics. Although statistically discernible, the amount of variation explained by land use was not remarkable due to low partial correlations. At level II ecoregion spatial scales (southeastern USA plains, central USA plains, and a combination of the western Cordillera and the western interior basins and ranges), environmental setting variables were again more important predictors of stream physical characteristics, however, as the spatial scale decreased from national to regional, the portion of variability in stream physical characteristics explained by basin land use increased. Development of stream habitat indicators of land use will depend upon an understanding of relations between stream physical characteristics and environmental factors at multiple spatial scales. Smaller spatial scales will be necessary to reduce the confounding effects of variable environmental settings before the effects of land use can be reliably assessed. ?? Springer Science+Business Media B.V. 2006.

Association of Day Length and Weather Conditions with Physical Activity Levels in Older Community Dwelling People

PubMed Central

Witham, Miles D.; Donnan, Peter T.; Vadiveloo, Thenmalar; Sniehotta, Falko F.; Crombie, Iain K.; Feng, Zhiqiang; McMurdo, Marion E. T.

2014-01-01

Background Weather is a potentially important determinant of physical activity. Little work has been done examining the relationship between weather and physical activity, and potential modifiers of any relationship in older people. We therefore examined the relationship between weather and physical activity in a cohort of older community-dwelling people. Methods We analysed prospectively collected cross-sectional activity data from community-dwelling people aged 65 and over in the Physical Activity Cohort Scotland. We correlated seven day triaxial accelerometry data with daily weather data (temperature, day length, sunshine, snow, rain), and a series of potential effect modifiers were tested in mixed models: environmental variables (urban vs rural dwelling, percentage of green space), psychological variables (anxiety, depression, perceived behavioural control), social variables (number of close contacts) and health status measured using the SF-36 questionnaire. Results 547 participants, mean age 78.5 years, were included in this analysis. Higher minimum daily temperature and longer day length were associated with higher activity levels; these associations remained robust to adjustment for other significant associates of activity: age, perceived behavioural control, number of social contacts and physical function. Of the potential effect modifier variables, only urban vs rural dwelling and the SF-36 measure of social functioning enhanced the association between day length and activity; no variable modified the association between minimum temperature and activity. Conclusions In older community dwelling people, minimum temperature and day length were associated with objectively measured activity. There was little evidence for moderation of these associations through potentially modifiable health, environmental, social or psychological variables. PMID:24497925

Association of day length and weather conditions with physical activity levels in older community dwelling people.

PubMed

Witham, Miles D; Donnan, Peter T; Vadiveloo, Thenmalar; Sniehotta, Falko F; Crombie, Iain K; Feng, Zhiqiang; McMurdo, Marion E T

2014-01-01

Weather is a potentially important determinant of physical activity. Little work has been done examining the relationship between weather and physical activity, and potential modifiers of any relationship in older people. We therefore examined the relationship between weather and physical activity in a cohort of older community-dwelling people. We analysed prospectively collected cross-sectional activity data from community-dwelling people aged 65 and over in the Physical Activity Cohort Scotland. We correlated seven day triaxial accelerometry data with daily weather data (temperature, day length, sunshine, snow, rain), and a series of potential effect modifiers were tested in mixed models: environmental variables (urban vs rural dwelling, percentage of green space), psychological variables (anxiety, depression, perceived behavioural control), social variables (number of close contacts) and health status measured using the SF-36 questionnaire. 547 participants, mean age 78.5 years, were included in this analysis. Higher minimum daily temperature and longer day length were associated with higher activity levels; these associations remained robust to adjustment for other significant associates of activity: age, perceived behavioural control, number of social contacts and physical function. Of the potential effect modifier variables, only urban vs rural dwelling and the SF-36 measure of social functioning enhanced the association between day length and activity; no variable modified the association between minimum temperature and activity. In older community dwelling people, minimum temperature and day length were associated with objectively measured activity. There was little evidence for moderation of these associations through potentially modifiable health, environmental, social or psychological variables.

Effectiveness of CAI Package on Achievement in Physics of IX Standard Students

ERIC Educational Resources Information Center

Maheswari, I. Uma; Ramakrishnan, N.

2015-01-01

The present study is an experimental one in nature, to find out the effectiveness of CAI package on in Physics of IX std. students. For this purpose a CAI package was developed and validated. The validated CAI package formed an independent variable of this study. The dependent variable is students' achievements in physics content. In order to find…

The differential impact of job isostrain and home-work interference on indicators of physical and mental health in women and men.

PubMed

Casini, Annalisa; Clays, Els; Godin, Isabelle; De Backer, Guy; Kornitzer, Marcel; Kittel, France

2010-12-01

To evaluate (1) whether the physical and mental health of male workers differs from that of female workers, and, if so, whether (2) this is affected by the interplay between work and nonwork burden. We pooled two large Belgian databases (BELSTRESS III, SOMSTRESS) comprising data on 4810 (2847 women). Gender-specific logistic regressions were performed using a four-level variable as predictor. This combined two predictors: isolated job strain (isostrain) and home-work interference (HWI). Male workers are at greater risk of chronic fatigue when they experience high isostrain but not high HWI. Although accumulated high isostrain and high HWI affect women mainly via chronic fatigue, the same pattern has a greater impact on men's perceived health. There was no difference for the other patterns. To improve workers' well-being, organizations should develop work and nonwork balance policies specific for men and women.

Correlative and multivariate analysis of increased radon concentration in underground laboratory.

PubMed

Maletić, Dimitrije M; Udovičić, Vladimir I; Banjanac, Radomir M; Joković, Dejan R; Dragić, Aleksandar L; Veselinović, Nikola B; Filipović, Jelena

2014-11-01

The results of analysis using correlative and multivariate methods, as developed for data analysis in high-energy physics and implemented in the Toolkit for Multivariate Analysis software package, of the relations of the variation of increased radon concentration with climate variables in shallow underground laboratory is presented. Multivariate regression analysis identified a number of multivariate methods which can give a good evaluation of increased radon concentrations based on climate variables. The use of the multivariate regression methods will enable the investigation of the relations of specific climate variable with increased radon concentrations by analysis of regression methods resulting in 'mapped' underlying functional behaviour of radon concentrations depending on a wide spectrum of climate variables. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Predictors of physical performance and functional ability in people 50+ with and without fibromyalgia.

PubMed

Jones, C Jessie; Rutledge, Dana N; Aquino, Jordan

2010-07-01

The purposes of this study were to determine whether people with and without fibromyalgia (FM) age 50 yr and above showed differences in physical performance and perceived functional ability and to determine whether age, gender, depression, and physical activity level altered the impact of FM status on these factors. Dependent variables included perceived function and 6 performance measures (multidimensional balance, aerobic endurance, overall functional mobility, lower body strength, and gait velocity-normal or fast). Independent (predictor) variables were FM status, age, gender, depression, and physical activity level. Results indicated significant differences between adults with and without FM on all physical-performance measures and perceived function. Linear-regression models showed that the contribution of significant predictors was in expected directions. All regression models were significant, accounting for 16-65% of variance in the dependent variables.

Outpatient rehabilitation care process factors and clinical outcomes among patients discharged home following unilateral total knee arthroplasty.

PubMed

Brennan, Gerard P; Fritz, Julie M; Houck, L T C Kevin M; Hunter, Stephen J

2015-05-01

Research examining care process variables and their relationship to clinical outcomes after total knee arthroplasty has focused primarily on inpatient variables. Care process factors related to outpatient rehabilitation have not been adequately examined. We conducted a retrospective review of 321 patients evaluating outpatient care process variables including use of continuous passive motion, home health physical therapy, number of days from inpatient discharge to beginning outpatient physical therapy, and aspects of outpatient physical therapy (number of visits, length of stay) as possible predictors of pain and disability outcomes of outpatient physical therapy. Only the number of days between inpatient discharge and outpatient physical therapy predicted better outcomes, suggesting that this may be a target for improving outcomes after total knee arthroplasty for patients discharged directly home. Copyright © 2014 Elsevier Inc. All rights reserved.

Observations and Models of Highly Intermittent Phytoplankton Distributions

PubMed Central

Mandal, Sandip; Locke, Christopher; Tanaka, Mamoru; Yamazaki, Hidekatsu

2014-01-01

The measurement of phytoplankton distributions in ocean ecosystems provides the basis for elucidating the influences of physical processes on plankton dynamics. Technological advances allow for measurement of phytoplankton data to greater resolution, displaying high spatial variability. In conventional mathematical models, the mean value of the measured variable is approximated to compare with the model output, which may misinterpret the reality of planktonic ecosystems, especially at the microscale level. To consider intermittency of variables, in this work, a new modelling approach to the planktonic ecosystem is applied, called the closure approach. Using this approach for a simple nutrient-phytoplankton model, we have shown how consideration of the fluctuating parts of model variables can affect system dynamics. Also, we have found a critical value of variance of overall fluctuating terms below which the conventional non-closure model and the mean value from the closure model exhibit the same result. This analysis gives an idea about the importance of the fluctuating parts of model variables and about when to use the closure approach. Comparisons of plot of mean versus standard deviation of phytoplankton at different depths, obtained using this new approach with real observations, give this approach good conformity. PMID:24787740

Characterizing local variability in long‐period horizontal tilt noise

USGS Publications Warehouse

Rohde, M.D.; Ringler, Adam; Hutt, Charles R.; Wilson, David; Holland, Austin; Sandoval, L.D; Storm, Tyler

2017-01-01

Horizontal seismic data are dominated by atmospherically induced tilt noise at long periods (i.e., 30 s and greater). Tilt noise limits our ability to use horizontal data for sensitive seismological studies such as observing free earth modes. To better understand the local spatial variability of long‐period horizontal noise, we observe horizontal noise during quiet time periods in the Albuquerque Seismological Laboratory (ASL) underground vault using four small‐aperture array configurations. Each array comprises eight Streckeisen STS‐2 broadband seismometers. We analyze the spectral content of the data using power spectral density and magnitude‐squared coherence (γ2‐coherence). Our results show a high degree of spatial variability and frequency dependence in the long‐period horizontal wavefield. The variable nature of long‐period horizontal noise in the ASL vault suggests that it might be highly local in nature and not easily characterized by simple physical models when overall noise levels are low, making it difficult to identify locations in the vault with lower horizontal noise. This variability could be limiting our ability to apply coherence analysis for estimating horizontal sensor self‐noise and could also complicate various indirect methods for removing long‐period horizontal noise (e.g., collocated rotational sensor or microbarograph).

The Moderating Effects of Culture on Peer Deviance and Alcohol Use among High-Risk African-American Adolescents

ERIC Educational Resources Information Center

Nasim, Aashir; Belgrave, Faye Z.; Jagers, Robert J.; Wilson, Karen D.; Owens, Kristal

2007-01-01

African-American adolescents have lower rates of alcohol consumption than White youth. However, African-American youth suffer disproportionately more adverse social, mental, and physical health outcomes related to alcohol use. Affiliating with negative peers is a risk factor for alcohol initiation and consumption. Cultural variables have shown…

Gender, depression and physical impairment: an epidemiologic perspective from Aleppo, Syria

PubMed Central

Rastam, Samer; Ward, Kenneth D.; Maziak, Wasim

2010-01-01

Objective Examine the association of physical impairment with gender, depression, and socio-demographics in the community in Aleppo, Syria. Method We conducted a cross-sectional, population-based study in Aleppo on adults aged 18–65 (N = 2,038). We used a computerized interviewer-administered structured questionnaire. Physical impairment was measured via an adapted 12-item World Health Organization, Health State Description Individual Questionnaire which includes both physical and emotional items. We used physical impairment items score to classify individuals into low, middle, and high physical impairment category. Self-report of physician-diagnosed depression and chronic diseases active in the past year and their current treatment status were obtained. Results Sample mean age (SD) was 35.3 (12.1) years, 55% were female, and 4.5% had depression. Female gender, low socioeconomic status (SES), and depression were associated with high physical impairment. Women had more impairment (OR = 3.35, 95% CI: 2.15–5.21) with little change after controlling for depression and chronic diseases, but significantly decreased after controlling for socio-demographics (OR = 1.51, 95% CI: 0.84–2.73). The association with low (vs. high) SES was prominent (OR = 2.48, 95% CI: 1.32–4.67) after controlling for all variables. Depression’s association (OR = 4.85, 95% CI: 1.93–12.15) lost significance after controlling for chronic diseases (OR = 2.81, 95% CI: 0.96–8.25), but further adjustment for socio-demographics had little effect. Conclusion Women and individuals of low SES appear more vulnerable to physical impairment in the community in Aleppo. Depression’s association with physical impairment may be mediated through co-existing chronic diseases. Public health planning regarding physical impairment in Syria should encompass these as putative risk factors. PMID:20195569

The New Zealand rugby injury and performance project. III. Anthropometric and physical performance characteristics of players.

PubMed Central

Quarrie, K L; Handcock, P; Waller, A E; Chalmers, D J; Toomey, M J; Wilson, B D

1995-01-01

OBJECTIVE: To investigate the anthropometric and physical performance characteristics of New Zealand rugby players of different ages and both sexes. METHODS: 356 rugby players (264 male, 92 female) took part in the study during a single season. Playing grade ranged from schoolboys and schoolgirls to senior men and women. Assessment of height, weight, neck circumference, and somatotype was performed before the competitive rugby season. A battery of six physical performance assessments was completed after the anthropometry. Analysis of variance was used to examine differences in these variables between field positions and grades. RESULTS: Significant differences between forwards and backs on anthropometric and physical performance variables were apparent at all grades assessed. In terms of anthropometric characteristics, forwards of a given grade were generally taller, possessed greater body mass, and were more endomorphic and less ectomorphic than backs of the same grade. The backs tended to perform better on physical performance measures than forwards, being more aerobically fit, faster, more agile, and possessing a higher degree of muscular endurance. Differences in anthropometry and physical performance attributes were also apparent between players from the various grades. The players at higher levels were generally larger, and performed better on tests of physical performance than the players at lower levels. These differences were found in both sexes. CONCLUSIONS: The greater body mass of the forwards allows them to obtain greater momentum than the backs when sprinting. The ability to obtain greater momentum is important in the body contact phases of the game. Forwards may compromise their aerobic fitness and speed to some extent in order to maintain a high body mass. The anthropometric and physical performance characteristics of players appear to reflect the demands placed on them by the sport. PMID:8808542

Factors Influencing Physical Activity Behavior among Iranian Women with Type 2 Diabetes Using the Extended Theory of Reasoned Action

PubMed Central

Didarloo, Alireza; Ardebili, Hassan Eftekhar; Niknami, Shamsaddin; Hajizadeh, Ebrahim; Alizadeh, Mohammad

2011-01-01

Background Findings of most studies indicate that the only way to control diabetes and prevent its debilitating effects is through the continuous performance of self-care behaviors. Physical activity is a non-pharmacological method of diabetes treatment and because of its positive effects on diabetic patients, it is being increasingly considered by researchers and practitioners. This study aimed at determining factors influencing physical activity among diabetic women in Iran, using the extended theory of reasoned action in Iran. Methods A sample of 352 women with type 2 diabetes, referring to a Diabetes Clinic in Khoy, Iran, participated in the study. Appropriate instruments were designed to measure the desired variables (knowledge of diabetes, personal beliefs, subjective norms, perceived self-efficacy, behavioral intention and physical activity behavior). The reliability and validity of the instruments were examined and approved. Statistical analyses of the study were conducted by inferential statistical techniques (independent t-test, correlations and regressions) using the SPSS package. Results The findings of this investigation indicated that among the constructs of the model, self efficacy was the strongest predictor of intentions among women with type 2 diabetes and both directly and indirectly affected physical activity. In addition to self efficacy, diabetic patients' physical activity also was influenced by other variables of the model and sociodemographic factors. Conclusion Our findings suggest that the high ability of the theory of reasoned action extended by self-efficacy in forecasting and explaining physical activity can be a base for educational intervention. Educational interventions based on the proposed model are necessary for improving diabetics' physical activity behavior and controlling disease. PMID:22111043

Classification of Physical Activity: Information to Artificial Pancreas Control Systems in Real Time.

PubMed

Turksoy, Kamuran; Paulino, Thiago Marques Luz; Zaharieva, Dessi P; Yavelberg, Loren; Jamnik, Veronica; Riddell, Michael C; Cinar, Ali

2015-10-06

Physical activity has a wide range of effects on glucose concentrations in type 1 diabetes (T1D) depending on the type (ie, aerobic, anaerobic, mixed) and duration of activity performed. This variability in glucose responses to physical activity makes the development of artificial pancreas (AP) systems challenging. Automatic detection of exercise type and intensity, and its classification as aerobic or anaerobic would provide valuable information to AP control algorithms. This can be achieved by using a multivariable AP approach where biometric variables are measured and reported to the AP at high frequency. We developed a classification system that identifies, in real time, the exercise intensity and its reliance on aerobic or anaerobic metabolism and tested this approach using clinical data collected from 5 persons with T1D and 3 individuals without T1D in a controlled laboratory setting using a variety of common types of physical activity. The classifier had an average sensitivity of 98.7% for physiological data collected over a range of exercise modalities and intensities in these subjects. The classifier will be added as a new module to the integrated multivariable adaptive AP system to enable the detection of aerobic and anaerobic exercise for enhancing the accuracy of insulin infusion strategies during and after exercise. © 2015 Diabetes Technology Society.

Classification of Physical Activity

PubMed Central

Turksoy, Kamuran; Paulino, Thiago Marques Luz; Zaharieva, Dessi P.; Yavelberg, Loren; Jamnik, Veronica; Riddell, Michael C.; Cinar, Ali

2015-01-01

Physical activity has a wide range of effects on glucose concentrations in type 1 diabetes (T1D) depending on the type (ie, aerobic, anaerobic, mixed) and duration of activity performed. This variability in glucose responses to physical activity makes the development of artificial pancreas (AP) systems challenging. Automatic detection of exercise type and intensity, and its classification as aerobic or anaerobic would provide valuable information to AP control algorithms. This can be achieved by using a multivariable AP approach where biometric variables are measured and reported to the AP at high frequency. We developed a classification system that identifies, in real time, the exercise intensity and its reliance on aerobic or anaerobic metabolism and tested this approach using clinical data collected from 5 persons with T1D and 3 individuals without T1D in a controlled laboratory setting using a variety of common types of physical activity. The classifier had an average sensitivity of 98.7% for physiological data collected over a range of exercise modalities and intensities in these subjects. The classifier will be added as a new module to the integrated multivariable adaptive AP system to enable the detection of aerobic and anaerobic exercise for enhancing the accuracy of insulin infusion strategies during and after exercise. PMID:26443291

Exploring factors related to physical activity in cervical dystonia.

PubMed

Zetterberg, Lena; Urell, Charlotte; Anens, Elisabeth

2015-12-01

People with disabilities have reported worse health status than people without disabilities and receiving fewer preventive health services such as counseling around exercise habits. This is noteworthy considering the negative consequences associated with physical inactivity. No research has been conducted on physical activity in cervical dystonia (CD), despite its possible major impact on self-perceived health and disability. Considering the favorable consequences associated with physical activity it is important to know how to promote physical activity behavior in CD. Knowledge of variables important for such behavior in CD is therefore crucial. The aim of this study was to explore factors related to physical activity in individuals with cervical dystonia. Subjects included in this cross-sectional study were individuals diagnosed with CD and enrolled at neurology clinics (n = 369). Data was collected using one surface mailed self-reported questionnaire. Physical activity was the primary outcome variable, measured with the Physical Activity Disability Survey. Secondary outcome variables were: impact of dystonia measured with the Cervical Dystonia Impact Scale; fatigue measured with the Fatigue Severity Scale; confidence when carrying out physical activity measured with the Exercise Self-Efficacy Scale; confidence in performing daily activities without falling measured with the Falls Efficacy Scale; enjoyment of activity measured with Enjoyment of Physical Activity Scale, and social influences on physical activity measured with Social Influences on Physical Activity in addition to demographic characteristics such as age, education level and employment status. The questionnaire was completed by 173 individuals (47% response rate). The multivariate association between related variables and physical activity showed that employment, self-efficacy for physical activity, education level and consequences for daily activities explained 51% of the variance in physical activity (Adj R 0.51, F (5, 162) = 35.611, p = 0.000). Employment and self-efficacy for physical activity contributed most strongly to the association with physical activity. Considering the favorable consequences associated with physical activity it could be important to support the individuals with CD to remain in work and self-efficacy to physical activity as employment and self-efficacy had significant influence on physical activity level. Future research is needed to evaluate causal effects of physical activity on consequences related to CD.

Environmental, psychological, and social influences on physical activity among Japanese adults: structural equation modeling analysis.

PubMed

Ishii, Kaori; Shibata, Ai; Oka, Koichiro

2010-08-05

An understanding of the contributing factors to be considered when examining how individuals engage in physical activity is important for promoting population-based physical activity. The environment influences long-term effects on population-based health behaviors. Personal variables, such as self-efficacy and social support, can act as mediators of the predictive relationship between the environment and physical activity. The present study examines the direct and indirect effects of environmental, psychological, and social factors on walking, moderate-intensity activity excluding walking, and vigorous-intensity activity among Japanese adults. The participants included 1,928 Japanese adults aged 20-79 years. Seven sociodemographic attributes (e.g., gender, age, education level, employment status), psychological variables (self-efficacy, pros, and cons), social variables (social support), environmental variables (home fitness equipment, access to facilities, neighborhood safety, aesthetic sensibilities, and frequency of observing others exercising), and the International Physical Activity Questionnaire were assessed via an Internet-based survey. Structural equation modeling was conducted to determine associations between environmental, psychological, and social factors with physical activity. Environmental factors could be seen to have indirect effects on physical activity through their influence on psychological and social variables such as self-efficacy, pros and cons, and social support. The strongest indirect effects could be observed by examining the consequences of environmental factors on physical activity through cons to self-efficacy. The total effects of environmental factors on physical activity were 0.02 on walking, 0.02 on moderate-intensity activity excluding walking, and 0.05 on vigorous-intensity activity. The present study indicates that environmental factors had indirect effects on walking, moderate-intensity activity excluding walking and vigorous-intensity activity among Japanese adults, especially through the effects on these factors of self-efficacy, social support, and pros and cons. The findings of the present study imply that intervention strategies to promote more engagement in physical activity for population-based health promotion may be necessary.

Environmental, psychological, and social influences on physical activity among Japanese adults: structural equation modeling analysis

PubMed Central

2010-01-01

Background An understanding of the contributing factors to be considered when examining how individuals engage in physical activity is important for promoting population-based physical activity. The environment influences long-term effects on population-based health behaviors. Personal variables, such as self-efficacy and social support, can act as mediators of the predictive relationship between the environment and physical activity. The present study examines the direct and indirect effects of environmental, psychological, and social factors on walking, moderate-intensity activity excluding walking, and vigorous-intensity activity among Japanese adults. Methods The participants included 1,928 Japanese adults aged 20-79 years. Seven sociodemographic attributes (e.g., gender, age, education level, employment status), psychological variables (self-efficacy, pros, and cons), social variables (social support), environmental variables (home fitness equipment, access to facilities, neighborhood safety, aesthetic sensibilities, and frequency of observing others exercising), and the International Physical Activity Questionnaire were assessed via an Internet-based survey. Structural equation modeling was conducted to determine associations between environmental, psychological, and social factors with physical activity. Results Environmental factors could be seen to have indirect effects on physical activity through their influence on psychological and social variables such as self-efficacy, pros and cons, and social support. The strongest indirect effects could be observed by examining the consequences of environmental factors on physical activity through cons to self-efficacy. The total effects of environmental factors on physical activity were 0.02 on walking, 0.02 on moderate-intensity activity excluding walking, and 0.05 on vigorous-intensity activity. Conclusions The present study indicates that environmental factors had indirect effects on walking, moderate-intensity activity excluding walking and vigorous-intensity activity among Japanese adults, especially through the effects on these factors of self-efficacy, social support, and pros and cons. The findings of the present study imply that intervention strategies to promote more engagement in physical activity for population-based health promotion may be necessary. PMID:20684794

Non-variable TeV emission from the extended jet of a blazar in the stochastic acceleration scenario: the case of the hard TeV emission of 1ES 1101-232

NASA Astrophysics Data System (ADS)

Yan, Dahai; Zeng, Houdun; Zhang, Li

2012-08-01

The detections of X-ray emission from the kiloparsec-scale jets of blazars and radio galaxies could imply the existence of high-energy electrons in these extended jets, and these electrons could produce high-energy emission through the inverse Compton (IC) process. In this paper, we study the non-variable hard TeV emission from a blazar. The multiband emission consists of two components: (i) the traditional synchrotron self-Compton (SSC) emission from the inner jet; (ii) the emission produced via SSC and IC scattering of cosmic microwave background (CMB) photons (IC/CMB) and extragalactic background light (EBL) photons by relativistic electrons in the extended jet under the stochastic acceleration scenario. Such a model is applied to 1ES 1101-232. The results indicate the following. (i) The non-variable hard TeV emission of 1ES 1101-232, which is dominated by IC/CMB emission from the extended jet, can be reproduced well by using three characteristic values of the Doppler factor (δD = 5, 10 and 15) for the TeV-emitting region in the extended jet. (ii) In the cases of δD = 15 and 10, the physical parameters can achieve equipartition (or quasi-equipartition) between the relativistic electrons and the magnetic field. In contrast, the physical parameters largely deviate from equipartition for the case of δD = 5. Therefore, we conclude that the TeV emission region of 1ES 1101-232 in the extended jet should be moderately or highly beamed.

A multi-level examination of school programs, policies and resources associated with physical activity among elementary school youth in the PLAY-ON study

PubMed Central

2010-01-01

Background Given the decline in physical activity (PA) levels among youth populations it is vital to understand the factors that are associated with PA in order to inform the development of new prevention programs. Many studies have examined individual characteristics associated with PA among youth yet few have studied the relationship between the school environment and PA despite knowing that there is variability in student PA levels across schools. Methods Using multi-level logistic regression analyses we explored the school- and student-level characteristics associated with PA using data from 2,379 grade 5 to 8 students attending 30 elementary schools in Ontario, Canada as part of the PLAY-Ontario study. Results Findings indicate that there was significant between-school random variation for being moderately and highly active; school-level differences accounted for 4.8% of the variability in the odds of being moderately active and 7.3% of the variability in the odds of being highly active. Students were more likely to be moderately active if they attended a school that used PA as a reward and not as discipline, and students were more likely to be highly active if they attended a school with established community partnerships. Important student characteristics included screen time sedentary behaviour, participating in team sports, and having active friends. Conclusion Future research should evaluate if the optimal population level impact for school-based PA promotion programming might be achieved most economically if intervention selectively targeted the schools that are putting students at the greatest risk for inactivity. PMID:20181010

Perceived neighborhood environment and physical activity among high school students from Curitiba, Brazil.

PubMed

Lopes, Adalberto Aparecido dos Santos; Lanzoni, Alessandra Nunes; Hino, Adriano Akira Ferreira; Rodriguez-Añez, Ciro Romélio; Reis, Rodrigo Siqueira

2014-12-01

To analyze the association between perceived neighborhood environment and physical activity (PA) in high school students from Curitiba (PR), Brazil. A sample of 1,611 high school students from public schools was surveyed. The PA was assessed through questions, engaged for at least 20 minutes or 60 minutes. Perceptions on neighborhood environment were assessed through ten questions about neighborhood characteristics. Gender, age and number of cars in the household were self-reported and used as confounding variables. Absolute and relative frequencies were used in the sample, and associations were tested through adjusted logistic regressions for the confounding variables and stratified by gender (p < 0.05). The adjusted analyses showed that the variables "interesting things" among girls (OR = 1.77; 95%CI 1.05 - 2.96) and "there are places I like" (OR = 2.18; 95%CI 1.33 - 3.58) and "I see people my age", among boys, were associated with PA of at least 20 minutes/day once a week. Additionally, among boys, "I see people my age" was associated with 60-minute (OR = 1.68; 95%CI 1.15 - 2.45). Perceiving the neighborhood environment as "very good" was associated with higher chances of taking up PA among girls (OR = 1.92; 95%CI 1.15 - 3.22) and boys (OR = 3.13; 95%CI 1.97 - 4.97). A positive perception of the environment was associated to PA practice among boys and girls in this sample. The results suggest that some environmental characteristics which make neighborhoods more attractive could be related to PA among adolescents.

Separating physical and biological controls on ten-year evapotranspiration fluctuations in an irrigated cropland in the North China Plain

NASA Astrophysics Data System (ADS)

Lei, Huimin

2016-04-01

The North China Plain, the largest agricultural production area in China, is a water-limited region where more than 50% of the nation's wheat and 33% of its maize production is grown. Evapotranspiration (ET) is a major component of the water balance in this agricultural ecosystem. Thus, hydrological cycle is very sensitive to the seasonal and interannual variability in ET. Understanding the variability in ET at different temporal scales and identifying out the dominant factor among the climatic factors (i.e., physical factors), crop factors (i.e., biological factors), and anthropogenic factors (i.e., irrigation) regulating ET is vital for promoting the development of agro-hydrological modeling. However, little is known about how ecosystem-level ET of irrigated cropland responds to these physical and biological factors over the long term, e.g., greater than 10 years. We have operated an eddy-covariance tower in a winter wheat-summer maize cropland for a 10-year period from 2005 through 2015, providing continuous measurements of ET and its relevant variables. The 10-year measurement period covers episodes of extremely high to low annual precipitation and higher air temperatures. The 10-year dataset provides opportunity to investigate the response of site-specific ecosystem ET to the variability of environmental factors. In this study, we reconcile an agro-hydrological model and the observations, to separate the physical and biological controls on ET fluctuations at different temporal scales. First, the model is calibrated carefully based on the observations. Second, a number of model runs are designed to disentangle the influence of climate, irrigation and biological drivers through constrained simulations. The climate drivers include precipitation, air temperature, air humidity, wind speed, and solar radiation, and the biological drivers include leaf area index and leaf-level stomatal conductance. In addition, the impacts of the variability in irrigation on ET will be studied. Last, based on the numerical runs, the dominant factor at each temporal scale (i.e., from weekly to annual) is identified.

Arctic storms simulated in atmospheric general circulation models under uniform high, uniform low, and variable resolutions

NASA Astrophysics Data System (ADS)

Roesler, E. L.; Bosler, P. A.; Taylor, M.

2016-12-01

The impact of strong extratropical storms on coastal communities is large, and the extent to which storms will change with a warming Arctic is unknown. Understanding storms in reanalysis and in climate models is important for future predictions. We know that the number of detected Arctic storms in reanalysis is sensitive to grid resolution. To understand Arctic storm sensitivity to resolution in climate models, we describe simulations designed to identify and compare Arctic storms at uniform low resolution (1 degree), at uniform high resolution (1/8 degree), and at variable resolution (1 degree to 1/8 degree). High-resolution simulations resolve more fine-scale structure and extremes, such as storms, in the atmosphere than a uniform low-resolution simulation. However, the computational cost of running a globally uniform high-resolution simulation is often prohibitive. The variable resolution tool in atmospheric general circulation models permits regional high-resolution solutions at a fraction of the computational cost. The storms are identified using the open-source search algorithm, Stride Search. The uniform high-resolution simulation has over 50% more storms than the uniform low-resolution and over 25% more storms than the variable resolution simulations. Storm statistics from each of the simulations is presented and compared with reanalysis. We propose variable resolution as a cost-effective means of investigating physics/dynamics coupling in the Arctic environment. Future work will include comparisons with observed storms to investigate tuning parameters for high resolution models. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND2016-7402 A

A Potential Function Derivation of a Constitutive Equation for Inelastic Material Response

NASA Technical Reports Server (NTRS)

Stouffer, D. C.; Elfoutouh, N. A.

1983-01-01

Physical and thermodynamic concepts are used to develop a potential function for application to high temperature polycrystalline material response. Inherent in the formulation is a differential relationship between the potential function and constitutive equation in terms of the state variables. Integration of the differential relationship produces a state variable evolution equation that requires specification of the initial value of the state variable and its time derivative. It is shown that the initial loading rate, which is directly related to the initial hardening rate, can significantly influence subsequent material response. This effect is consistent with observed material behavior on the macroscopic and microscopic levels, and may explain the wide scatter in response often found in creep testing.

Physical activity behavior and related characteristics of highly active eighth-grade girls.

PubMed

Taverno Ross, Sharon E; Dowda, Marsha; Beets, Michael W; Pate, Russell R

2013-06-01

Although girls are generally less physically active than boys, some girls regularly engage in high levels of physical activity (PA); however, very little is known about these girls and how they differ from those who are less physically active. This study examined the PA behavior and related characteristics of highly active adolescent girls and compared them with those who are less active. Data from 1,866 eighth-grade girls from six field centers across the United States participating in the Trial of Activity for Adolescent Girls (TAAG) were included in the present analysis. Mixed-model analysis of variance examined differences in sociodemographic, anthropometric, psychosocial, and physical activity (accelerometry and self-report) variables between high- and low-active girls; effect sizes were calculated for the differences. High-active girls were taller, had lower body mass indices and body fat, and were less sedentary. High-active girls scored higher on self-efficacy, enjoyment of PA, self-management strategies, outcome-expectancy value, and support from family and friends than low-active girls. Low-active girls participated in more leisure time and educational sedentary activities than high-active girls. High-active girls participated in more PA classes/lessons outside of school, team sports, and individual sports. They were also more likely to participate in sports in an organized setting in the community or at school than low-active girls. Health promotion efforts should focus on decreasing the amount of time girls spend in sedentary activities and replacing that time with organized PA opportunities; such efforts should seek to minimize perceived barriers and increase self-efficacy and support for PA. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Workplace bullying and relationships with health and performance among a sample of New Zealand veterinarians.

PubMed

Gardner, D H; Rasmussen, W

2018-03-01

To examine the relationships between workplace bullying, destructive leadership and team conflict, and physical health, strain, self-reported performance and intentions to quit among veterinarians in New Zealand, and how these relationships could be moderated by psychological capital and perceived organisational support. Data were collected by means of an online survey, distributed to members of the New Zealand Veterinary Association. Participation was voluntary and all responses were anonymous and confidential. Scores for the variables measured were based on responses to questions or statements with responses categorised on a linear scale. A series of regression analyses were used to assess mediation or moderation by intermediate variables on the relationships between predictor variables and dependent variables. Completed surveys were provided by 197 veterinarians, of which 32 (16.2%) had been bullied at work, i.e. they had experienced two or more negative acts at least weekly over the previous 6 months, and nine (4.6%) had experienced cyber-bullying. Mean scores for workplace bullying were higher for female than male respondents, and for non-managers than managers (p<0.01). Scores for workplace bullying were positively associated with scores for destructive leadership and team conflict, physical health, strain, and intentions to quit (p<0.001). Workplace bullying and team conflict mediated the relationship between destructive leadership and strain, physical health and intentions to quit. Perceived organisational support moderated the effects of workplace bullying on strain and self-reported job performance (p<0.05). Relatively high rates of negative behaviour were reported by veterinarians in this study, with 16% of participants meeting an established criterion for having been bullied. The negative effects of destructive leadership on strain, physical health and intentions to quit were mediated by team conflict and workplace bullying. It should be noted that the findings of this study were based on a survey of self-selected participants and the findings may not represent the wider population of New Zealand veterinarians.

Influence of school environments on childhood obesity in California.

PubMed

Ortega Hinojosa, Alberto M; MacLeod, Kara E; Balmes, John; Jerrett, Michael

2018-06-05

To conduct a state-wide examination of public schools and the school neighborhood as potential targets for environmental public health tracking to address childhood obesity. We examined the relationship of social and physical environmental attributes of the school environment (within school and neighborhood) and childhood obesity in California with machine learning (Random Forest) and multilevel methods. We used data compiled from the California Department of Education, the U.S. Geological Survey, ESRI's Business Analyst, the U.S. Census, and other public sources for ecologic level variables for various years and assessed their relative importance to obesity as determined from the statewide Physical Fitness Test 2003 through 2007 for grades 5, 7, and 9 (n = 5,265,265). In addition to individual-level race and gender, the following within and school neighborhood variables ranked as the most important model contributors based on the Random Forest analysis and were included in multilevel regressions clustered on the county. Violent crime, English learners, socioeconomic disadvantage, fewer physical education (PE) and fully credentialed teachers, and diversity index were positively associated with obesity while academic performance index, PE participation, mean educational attainment and per capita income were negatively associated with obesity. The most highly ranked built or physical environment variables were distance to the nearest highway and greenness, which were 10th and 11th most important, respectively. Many states in the U.S. do not have school-based surveillance programs that collect body mass index data. System-level determinants of obesity can be important for tracking and intervention. The results of these analyses suggest that the school social environment factors may be especially important. Disadvantaged and low academic performing schools have a higher risk for obesity. Supporting such schools in a targeted way may be an efficient way to intervene and could impact both health and academic outcomes. Some of the more important variables, such as having credentialed teachers and participating in PE, are modifiable risk factors. Copyright © 2018. Published by Elsevier Inc.

Depression, coronary artery disease, and physical activity: how much exercise is enough?

PubMed

Peterson, Janey C; Charlson, Mary E; Wells, Martin T; Altemus, Margaret

2014-11-01

The mechanisms by which depressive symptoms negatively affect clinical outcomes in patients with coronary artery disease (CAD) remain poorly understood. Previous interventions that have attempted to treat depressive symptoms in patients with CAD to improve their clinical outcomes have been disappointing. Our objectives were, among a cohort of CAD patients, to evaluate the impact of depressive symptoms over time, controlling for comorbidity, in determining both successful long-term lifestyle change (ie, increased physical activity), and cardiovascular morbidity and mortality outcomes. In addition, we examined the impact of physical activity changes over time on 2 known mediators of cardiovascular morbidity: parasympathetic tone and inflammation. Clinical data were previously collected (2004-2006) from 242 elective/urgent coronary angioplasty patients who participated in a prospective randomized controlled trial evaluating the efficacy of a behavioral intervention versus an educational control to motivate physical activity over 12 months. Exclusion criteria included: (1) inability to walk; (2) enrollment in other risk-reduction trials; (3) non-English speaking; and (4) lack of cardiologist's permission to increase physical activity. Participants were assessed every 2 months for interval clinical events and physical activity. In addition, biomarkers were collected at baseline and at 12 months in a subset of 54 participants; these biomarkers included low-frequency heart rate variability (lfHRV), high-frequency heart rate variability (hfHRV), serum C-reactive protein, interleukin-6, and salivary cortisol. The mean age of participants was 63 years and 30% were female. Overall, 37% had high depressive symptoms at baseline. Patients with high depressive symptoms who achieved an increase in physical activity of ≥336 kilocalories(kcal)/week by 12 months had significantly lower rates of cardiovascular morbidity/mortality (5.1% vs. 21.3%; odds ratio [OR], 0.20, [95% CI, 0.04-0.98]; P = 0.03). In a multivariate model examining cardiovascular morbidity/mortality in patients with high depressive symptoms, an increase in physical activity of ≥336 kcal/week reduced the risk of new cardiovascular morbidity/mortality (OR, 0.11 [95% CI, 0.02-0.81]; P < 0.03), and comorbidity increased the risk (OR, 1.58 [95% CI, 1.18-2.13]; P = 0.002). In a generalized structural equation model, increasing physical activity by ≥336 kcal/week decreased the risk of complications, and comorbidity increased the risk. Furthermore, increasing physical activity (≥336 kcal/week) predicted an increase in hfHRV, a marker of parasympathetic tone, and the increase in hfHRV predicted a reduction in the proinflammatory mediators interleukin-6 and C-reactive protein. This study found a threshold in physical activity in CAD patients with depressive symptoms that is associated with a decrease in cardiovascular morbidity and mortality. Exercise maintenance at this level may improve clinical outcomes via enhanced parasympathetic tone and decreased inflammation. ClinicalTrials.gov identifier: NCT00248846. Copyright © 2014 Elsevier HS Journals, Inc. All rights reserved.

Perceived barriers to physical activity among Nigerian stroke survivors.

PubMed

Idowu, Opeyemi Ayodiipo; Adeniyi, Ade Fatai; Ogwumike, Omoyemi Olubunmi; Fawole, Henrietta Oluwafunmilola; Akinrolie, Olayinka

2015-01-01

Benefits of physical activity in the prevention and management of stroke are well documented in the literature. There is increasing evidence that stroke survivors in South-West Nigeria are physically inactive. Data on barriers to the achievement of the recommended physical activity levels including its differences along socio-demographic characteristics among stroke survivors in South-West Nigeria are needed. The Exercise Benefits and Barrier Scale and the International Physical Activity Questionnaire were administered on 121 stroke survivors to determine their perceived barriers to physical activity and physical activity levels respectively. Information on socio-demographic data and clinical variables were also collected. The sample included 70.2% males, with majority of the participants reporting low physical activity levels (80.2%) and high perceived barriers (Mean = 48.13, SD = 7.88). The four most reported common barriers among stroke survivors were access to exercise facilities (95.0%), being embarrassed to exercise (94.2%), economic cost demands of exercise (94.2%) and notion that people in exercise clothes look funny (94.2%) respectively. There were no significant differences found in barriers to physical activity between gender (U = 1471.00, P = 0.74) and across each of: occupational status (H = 4.37, P = 0.22), age group (H = 0.82, P = 0.84) and educational levels (H = 4.56, P = 0.33). Significant difference however existed in perceived barriers across marital status categories (H = 12.87, P = 0.05). Stroke survivors indicated high perceived barriers to physical activity and these barriers were associated with marital status.

Variability in the American Society of Anesthesiologists (ASA) Physical Status (PS) Classification Scale

DTIC Science & Technology

2000-01-03

was altered by several variables (patient condition, planned surgical procedure, experience and skill of surgeon and anesthetist, and attention to...be developed. Variables in addition to the patient physical status ( experience of the surgeon, anesthetist, and hospital personnel) could be entered...specific surgery. Surgical risks include experience of the surgical team, the medical institution, elective versus emergent, availability of

Exploring the facilitators and barriers to engagement in physical activity for people with multiple sclerosis.

PubMed

Kayes, Nicola M; McPherson, Kathryn M; Schluter, Philip; Taylor, Denise; Leete, Marta; Kolt, Gregory S

2011-01-01

To explore the relationship that cognitive behavioural and other previously identified variables have with physical activity engagement in people with multiple sclerosis (MS). This study adopted a cross-sectional questionnaire design. Participants were 282 individuals with MS. Outcome measures included the Physical Activity Disability Survey--Revised, Cognitive and Behavioural Responses to Symptoms Questionnaire, Barriers to Health Promoting Activities for Disabled Persons Scale, Multiple Sclerosis Self-efficacy Scale, Self-Efficacy for Chronic Diseases Scales and Chalder Fatigue Questionnaire. Multivariable stepwise regression analyses found that greater self-efficacy, greater reported mental fatigue and lower number of perceived barriers to physical activity accounted for a significant proportion of variance in physical activity behaviour, over that accounted for by illness-related variables. Although fear-avoidance beliefs accounted for a significant proportion of variance in the initial analyses, its effect was explained by other factors in the final multivariable analyses. Self-efficacy, mental fatigue and perceived barriers to physical activity are potentially modifiable variables which could be incorporated into interventions designed to improve physical activity engagement. Future research should explore whether a measurement tool tailored to capture beliefs about physical activity identified by people with MS would better predict participation in physical activity.

High-resolution numerical approximation of traffic flow problems with variable lanes and free-flow velocities.

PubMed

Zhang, Peng; Liu, Ru-Xun; Wong, S C

2005-05-01

This paper develops macroscopic traffic flow models for a highway section with variable lanes and free-flow velocities, that involve spatially varying flux functions. To address this complex physical property, we develop a Riemann solver that derives the exact flux values at the interface of the Riemann problem. Based on this solver, we formulate Godunov-type numerical schemes to solve the traffic flow models. Numerical examples that simulate the traffic flow around a bottleneck that arises from a drop in traffic capacity on the highway section are given to illustrate the efficiency of these schemes.

Examination of Studying Approaches of Students at School of Physical Education and Sports in Terms of Different Variables

ERIC Educational Resources Information Center

Dereceli, Cagatay

2017-01-01

This study aims to examine studying approaches of the students of physical education and school of physical and sports according to various variables. The data of the study conducted in the general scanning model has been collected from 478 students in 2016-2017 teaching year. Studying Approaches Scale has been used to collect data. Besides…

Investigation of the Attitudes of Physical Education Teacher Candidates toward Teaching Profession and Sense of Competence in Terms of Some Variables

ERIC Educational Resources Information Center

Murathan, Talha; Özdemir, Kübra

2017-01-01

The purpose of this study was to examine the attitudes of physical education teacher candidates toward the teaching profession and the perceptions of professional competence according to some variables. A total of 351 teacher candidates, studying in the last class of Physical Education and Sport Teaching Department in the Faculty of Sports…

Relationship between health-related quality of life, perceived family support and unmet health needs in adult patients with multimorbidity attending primary care in Portugal: a multicentre cross-sectional study.

PubMed

Prazeres, Filipe; Santiago, Luiz

2016-11-11

Multimorbidity has a high prevalence in the primary care context and it is frequently associated with worse health-related quality of life (HRQoL). Few studies evaluated the variables that could have a potential effect on HRQoL of primary care patients with multimorbidity. The purpose of this study, the first of its kind ever undertaken in Portugal, is to analyse the relationship between multimorbidity, health-related quality of life, perceived family support and unmet health needs in adult patients attending primary care. Multicentre, cross-sectional survey conducted among primary care patients with multimorbidity. It included 521 participants (64.1 % females) who met the inclusion criteria. HRQoL was evaluated using the Portuguese Short Form-12 Health Status Questionnaire. The Portuguese Family APGAR was used to measure the perceived family support. A patients' unmet health needs questionnaire was used. The unmet needs for medical, surgical and dental care; prescription medications; mental healthcare or counselling; and eyeglasses or other technical aid was assessed. Descriptive and multivariate analyses were performed. The sample had an overall average of 4.5 chronic health problems. Increased multimorbidity levels were linked to worse health-related quality of life, particularly the physical health. Some variables were confirmed as playing a role on health-related quality of life. Male patients with high monthly incomes and highly functional families had better physical and mental health. High levels of education and the presence of asthma were also associated with better physical health. Contrariwise, elderly patients with high levels of multimorbidity and with osteoarthritis had lower physical health. The majority of the patients did not have unmet health needs. When health needs were stated they were mostly for generalist medical care, dental care, and eyeglasses/other technical aid. Financial insufficiency was the primary reason for not fulfilling their health needs. To improve the quality of life of multimorbid patients, within primary care practices and health delivery systems, one should take into special account the sex of the patient, the perceived family support and the self-perceived economic status because of their relationship with both physical and mental health. Limitations and recommendations are discussed.

Small-scale variability in tropical tropopause layer humidity

NASA Astrophysics Data System (ADS)

Jensen, E. J.; Ueyama, R.; Pfister, L.; Karcher, B.; Podglajen, A.; Diskin, G. S.; DiGangi, J. P.; Thornberry, T. D.; Rollins, A. W.; Bui, T. V.; Woods, S.; Lawson, P.

2016-12-01

Recent advances in statistical parameterizations of cirrus cloud processes for use in global models are highlighting the need for information about small-scale fluctuations in upper tropospheric humidity and the physical processes that control the humidity variability. To address these issues, we have analyzed high-resolution airborne water vapor measurements obtained in the Airborne Tropical TRopopause EXperiment over the tropical Pacific between 14 and 20 km. Using accurate and precise 1-Hz water vapor measurements along approximately-level aircraft flight legs, we calculate structure functions spanning horizontal scales ranging from about 0.2 to 50 km, and we compare the water vapor variability in the lower (about 14 km) and upper (16-19 km) Tropical Tropopause Layer (TTL). We also compare the magnitudes and scales of variability inside TTL cirrus versus in clear-sky regions. The measurements show that in the upper TTL, water vapor concentration variance is stronger inside cirrus than in clear-sky regions. Using simulations of TTL cirrus formation, we show that small variability in clear-sky humidity is amplified by the strong sensitivity of ice nucleation rate to supersaturation, which results in highly-structured clouds that subsequently drive variability in the water vapor field. In the lower TTL, humidity variability is correlated with recent detrainment from deep convection. The structure functions indicate approximately power-law scaling with spectral slopes ranging from about -5/3 to -2.

Eddy-driven low-frequency variability: physics and observability through altimetry

NASA Astrophysics Data System (ADS)

Penduff, Thierry; Sérazin, Guillaume; Arbic, Brian; Mueller, Malte; Richman, James G.; Shriver, Jay F.; Morten, Andrew J.; Scott, Robert B.

2015-04-01

Model studies have revealed the propensity of the eddying ocean circulation to generate strong low-frequency variability (LFV) intrinsically, i.e. without low-frequency atmospheric variability. In the present study, gridded satellite altimeter products, idealized quasi-geostrophic (QG) turbulent simulations, and realistic high-resolution global ocean simulations are used to study the spontaneous tendency of mesoscale (relatively high frequency and high wavenumber) kinetic energy to non-linearly cascade towards larger time and space scales. The QG model reveals that large-scale variability, arising from the well-known spatial inverse cascade, is associated with low frequencies. Low-frequency, low-wavenumber energy is maintained primarily by nonlinearities in the QG model, with forcing (by large-scale shear) and friction playing secondary roles. In realistic simulations, nonlinearities also generally drive kinetic energy to low frequencies and low wavenumbers. In some, but not all, regions of the gridded altimeter product, surface kinetic energy is also found to cascade toward low frequencies. Exercises conducted with the realistic model suggest that the spatial and temporal filtering inherent in the construction of gridded satellite altimeter maps may contribute to the discrepancies seen in some regions between the direction of frequency cascade in models versus gridded altimeter maps. Finally, the range of frequencies that are highly energized and engaged these cascades appears much greater than the range of highly energized and engaged wavenumbers. Global eddying simulations, performed in the context of the CHAOCEAN project in collaboration with the CAREER project, provide estimates of the range of timescales that these oceanic nonlinearities are likely to feed without external variability.

Prediction of performance on the RCMP physical ability requirement evaluation.

PubMed

Stanish, H I; Wood, T M; Campagna, P

1999-08-01

The Royal Canadian Mounted Police use the Physical Ability Requirement Evaluation (PARE) for screening applicants. The purposes of this investigation were to identify those field tests of physical fitness that were associated with PARE performance and determine which most accurately classified successful and unsuccessful PARE performers. The participants were 27 female and 21 male volunteers. Testing included measures of aerobic power, anaerobic power, agility, muscular strength, muscular endurance, and body composition. Multiple regression analysis revealed a three-variable model for males (70-lb bench press, standing long jump, and agility) explaining 79% of the variability in PARE time, whereas a one-variable model (agility) explained 43% of the variability for females. Analysis of the classification accuracy of the males' data was prohibited because 91% of the males passed the PARE. Classification accuracy of the females' data, using logistic regression, produced a two-variable model (agility, 1.5-mile endurance run) with 93% overall classification accuracy.

The Mathematics of High School Physics

NASA Astrophysics Data System (ADS)

Kanderakis, Nikos

2016-10-01

In the seventeenth and eighteenth centuries, mathematicians and physical philosophers managed to study, via mathematics, various physical systems of the sublunar world through idealized and simplified models of these systems, constructed with the help of geometry. By analyzing these models, they were able to formulate new concepts, laws and theories of physics and then through models again, to apply these concepts and theories to new physical phenomena and check the results by means of experiment. Students' difficulties with the mathematics of high school physics are well known. Science education research attributes them to inadequately deep understanding of mathematics and mainly to inadequate understanding of the meaning of symbolic mathematical expressions. There seem to be, however, more causes of these difficulties. One of them, not independent from the previous ones, is the complex meaning of the algebraic concepts used in school physics (e.g. variables, parameters, functions), as well as the complexities added by physics itself (e.g. that equations' symbols represent magnitudes with empirical meaning and units instead of pure numbers). Another source of difficulties is that the theories and laws of physics are often applied, via mathematics, to simplified, and idealized physical models of the world and not to the world itself. This concerns not only the applications of basic theories but also all authentic end-of-the-chapter problems. Hence, students have to understand and participate in a complex interplay between physics concepts and theories, physical and mathematical models, and the real world, often without being aware that they are working with models and not directly with the real world.

Depressive symptoms and social demographic, stress and health risk behaviour among university students in 26 low-, middle- and high-income countries.

PubMed

Peltzer, Karl; Pengpid, Supa

2015-01-01

The aim of this study was to determine the prevalence and association between depressive symptoms, sociodemographic, social and health risk variables among undergraduate students in 26 low, middle and high income countries. Using anonymous questionnaires, data were collected from 20222 undergraduate university students (mean age 20.8, SD = 2.8) from 27 universities in 26 countries in Africa, Asia, Caribbean and Latin America. Overall study participants had a prevalence of 24.0 % moderate and 12.8 % severe depressive symptoms. In multivariate logistic regression, demographic and social variables (being female gender, low organised religious activity, lack of social support and lack of personal control), stressful or traumatic life events (sexual violence and physical child abuse) and health risk behaviour (tobacco use, insufficient brushing of teeth, irregular sleep duration, increased salt intake, infrequent meals a day, heavy internet use and having sustained an injury) were associated with severe depressive symptoms. High rates of depressive symptoms were found. Several risk factors including social and health risk behaviour variables were identified which can be utilised in guiding interventions.

Perceived individual, social, and environmental factors for physical activity and walking.

PubMed

Granner, Michelle L; Sharpe, Patricia A; Hutto, Brent; Wilcox, Sara; Addy, Cheryl L

2007-07-01

Few studies have explored associations of individual, social, and environmental factors with physical activity and walking behavior. A random-digit-dial questionnaire, which included selected individual, social, and environmental variables, was administered to 2025 adults, age 18 y and older, in two adjacent counties in a southeastern state. Logistic regressions were conducted adjusting for age, race, sex, education, and employment. In multivariate models, somewhat different variables were associated with physical activity versus regular walking. Self-efficacy (OR = 19.19), having an exercise partner (OR = 1.47), recreation facilities (OR = 1.54), and safety of trails from crime (OR = 0.72) were associated with physical activity level; while self-efficacy (OR = 4.22), known walking routes (OR = 1.54), recreation facilities (OR = 1.57-1.59), and safety of trails from crime (OR = 0.69) were associated with regular walking behavior. Physical activity and walking behaviors were associated with similar variables in this study.

Intraindividual variability in cognitive performance in three groups of older adults: cross-domain links to physical status and self-perceived affect and beliefs.

PubMed

Strauss, Esther; MacDonald, Stuart W S; Hunter, Michael; Moll, Alex; Hultsch, David F

2002-11-01

Intraindividual variability of physical status and affect/beliefs as well as their relations with cognition were examined in 3 groups of older adults: healthy elderly, individuals with a nonneurological health-related disturbance (arthritis) and people with neurological compromise (dementia). The findings showed that greater inconsistency in physical performance was observed in groups characterized by central nervous system dysfunction. By contrast, fluctuations in affect appeared to reflect other more transient sources, such as pain. In general, increased inconsistency in non-cognitive domains was associated with poorer cognitive function. There were cross-domain links between inconsistency in physical functioning and fluctuations in cognitive performance, although the nature of the links depended largely upon the neurological status of the individuals. Considered together, the result indicated that measures of cognitive as well as physical variability are important behavioral markers of neurological integrity.

[Anxiety, self-esteem and self-perceived satisfaction as predictors of health: differences between men and women].

PubMed

Sánchez López, María Pilar; Aparicio García, Marta Evelia; Dresch, Virginia

2006-08-01

The main objective of this research is to analyze whether there are differences in physical health between men and women when considering their working situation. Three psychological variables are analyzed (anxiety, self-esteem and satisfaction) as well as several indicators of physical health for different working situations. The results seem to indicate that although women have worse health than men (when the group is analyzed in general), these differences vary when we take into account the working condition of the participants, and the differences even disappear. The psychological variables used in this survey only explain the variance of the subjective indicators of physical health, most of all, the Physiological Anxiety, which is responsible for the highest rate of the explained variance. The psychological variables predict women's physical health more than men's, what seems to indicate that women's physical health is closely related to psychological health.

Air flow and pollution in a real, heterogeneous urban street canyon: A field and laboratory study

NASA Astrophysics Data System (ADS)

Karra, Styliani; Malki-Epshtein, Liora; Neophytou, Marina K.-A.

2017-09-01

In this work we investigate the influence of real world conditions, including heterogeneity and natural variability of background wind, on the air flow and pollutant concentrations in a heterogeneous urban street canyon using both a series of field measurements and controlled laboratory experiments. Field measurements of wind velocities and Carbon Monoxide (CO) concentrations were taken under field conditions in a heterogeneous street in a city centre at several cross-sections along the length of the street (each cross-section being of different aspect ratio). The real field background wind was in fact observed to be highly variable and thus different Intensive Observation Periods (IOPs) represented by a different mean wind velocity and different wind variability were defined. Observed pollution concentrations reveal high sensitivity to local parameters: there is a bias towards the side closer to the traffic lane; higher concentrations are found in the centre of the street as compared to cross-sections closer to the junctions; higher concentrations are found at 1.5 height from the ground than at 2.5 m height, all of which are of concern regarding pedestrian exposure to traffic-related pollution. A physical model of the same street was produced for the purpose of laboratory experiments, making some geometrical simplifications of complex volumes and extrusions. The physical model was tested in an Atmospheric Boundary Layer water channel, using simultaneously Particle Image Velocimetry (PIV) and Planar Laser Induced Fluorescence (PLIF), for flow visualisation as well as for quantitative measurement of concentrations and flow velocities. The wind field conditions were represented by a steady mean approach velocity in the laboratory simulation (essentially representing periods of near-zero wind variability). The laboratory investigations showed a clear sensitivity of the resulting flow field to the local geometry and substantial three-dimensional flow patterns were observed throughout the modelled street. The real-field observations and the laboratory measurements were compared. Overall, we found that lower variability in the background wind does not necessarily ensure a better agreement between the airflow velocity measured in the field and in the lab. In fact, it was observed that in certain cross sections, the airflow was more affected by the particular complex architectural features such as building extrusions and balconies, which were not represented in the simplified physical model tested in the laboratory, than by the real wind field variability. For wind speed comparisons the most favourable agreement (36.6% of the compared values were within a factor of 2) was found in the case of lowest wind variability and in the section with the most simple geometry where the physical lab model was most similar to the real street. For wind direction comparisons the most favourable agreement (45.5% of the compared values was within ±45°) was found in the case with higher wind variability but in the cross-sections with more homogeneous geometrical features. Street canyons are often simplified in research and are often modelled as homogenous symmetrical canyons under steady flow, for practical purposes; our study as a whole demonstrates that natural variability and heterogeneity play a large role in how pollution disperses throughout the street, and therefore further detail in models is vital to understand real world conditions.

Using "human state aware" robots to enhance physical human-robot interaction in a cooperative scenario.

PubMed

Guerrero, Carlos Rodriguez; Fraile Marinero, Juan Carlos; Turiel, Javier Perez; Muñoz, Victor

2013-11-01

Human motor performance, speed and variability are highly susceptible to emotional states. This paper reviews the impact of the emotions on the motor control performance, and studies the possibility of improving the perceived skill/challenge relation on a multimodal neural rehabilitation scenario, by means of a biocybernetic controller that modulates the assistance provided by a haptic controlled robot in reaction to undesirable physical and mental states. Results from psychophysiological, performance and self assessment data for closed loop experiments in contrast with their open loop counterparts, suggest that the proposed method had a positive impact on the overall challenge/skill relation leading to an enhanced physical human-robot interaction experience. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Exploring psychosocial correlates of physical activity among children and adolescents with spina bifida.

PubMed

Marques, Adilson; Maldonado, Inês; Peralta, Miguel; Santos, Sofia

2015-01-01

To enhance physical activity of children with spina bifida, it is important to investigate the correlates of physical activity to support the development of interventions to promote active lifestyles. This study aimed to identify psychosocial correlates of physical activity among children and adolescents with spina bifida. A survey was conducted with 31 students (15 boys), aged 10-17 years with spina bifida. A questionnaire was used to collect data of physical activity, demographic and psychosocial variables (attitudes, sports goal orientation and perceptions). Unadjusted and adjusted binary logistic regressions were performed to examine the relationship of psychosocial factors and physical activity participation. Data were collected in 2013. Only 38.7% reported to participate in both organized and non-organized physical activity. Results showed no relationship between participation in organized and non-organized physical activity and psychosocial correlates. The result of the adjusted regression analysis show that perception of competence (OR = 9.55, 1.06-85.99, p < 0.05) was the only variable positively associated with participation in non-organized physical activity. Most of the participants reported that they did not participate in physical activity regularly. Psychosocial variables were not related with physical activity, except perception of competence. Studies with bigger samples are needed, focused on the same and in others factors to identify the predictors of physical activity of young people with spina bifida. Copyright © 2015 Elsevier Inc. All rights reserved.

Do Perceptions of Competence Mediate The Relationship Between Fundamental Motor Skill Proficiency and Physical Activity Levels of Children in Kindergarten?

PubMed

Crane, Jeff R; Naylor, Patti J; Cook, Ryan; Temple, Viviene A

2015-07-01

Perceptions of competence mediate the relationship between motor skill proficiency and physical activity among older children and adolescents. This study examined kindergarten children's perceptions of physical competence as a mediator of the relationship between motor skill proficiency as a predictor variable and physical activity levels as the outcome variable; and also with physical activity as a predictor and motor skill proficiency as the outcome. Participants were 116 children (mean age = 5 years 7 months, 58% boys) from 10 schools. Motor skills were measured using the Test of Gross Motor Development-2 and physical activity was monitored through accelerometry. Perceptions of physical competence were measured using The Pictorial Scale of Perceived Competence and Social Acceptance for Young Children, and the relationships between these variables were examined using a model of mediation. The direct path between object control skills and moderate-vigorous physical activity (MVPA) was significant and object control skills predicted perceived physical competence. However, perceived competence did not mediate the relationship between object control skills and MVPA. The significant relationship between motor proficiency and perceptions of competence did not in turn influence kindergarten children's participation in physical activity. These findings support concepts of developmental differences in the structure of the self-perception system.

Variable Lifting Index (VLI): A New Method for Evaluating Variable Lifting Tasks.

PubMed

Waters, Thomas; Occhipinti, Enrico; Colombini, Daniela; Alvarez-Casado, Enrique; Fox, Robert

2016-08-01

We seek to develop a new approach for analyzing the physical demands of highly variable lifting tasks through an adaptation of the Revised NIOSH (National Institute for Occupational Safety and Health) Lifting Equation (RNLE) into a Variable Lifting Index (VLI). There are many jobs that contain individual lifts that vary from lift to lift due to the task requirements. The NIOSH Lifting Equation is not suitable in its present form to analyze variable lifting tasks. In extending the prior work on the VLI, two procedures are presented to allow users to analyze variable lifting tasks. One approach involves the sampling of lifting tasks performed by a worker over a shift and the calculation of the Frequency Independent Lift Index (FILI) for each sampled lift and the aggregation of the FILI values into six categories. The Composite Lift Index (CLI) equation is used with lifting index (LI) category frequency data to calculate the VLI. The second approach employs a detailed systematic collection of lifting task data from production and/or organizational sources. The data are organized into simplified task parameter categories and further aggregated into six FILI categories, which also use the CLI equation to calculate the VLI. The two procedures will allow practitioners to systematically employ the VLI method to a variety of work situations where highly variable lifting tasks are performed. The scientific basis for the VLI procedure is similar to that for the CLI originally presented by NIOSH; however, the VLI method remains to be validated. The VLI method allows an analyst to assess highly variable manual lifting jobs in which the task characteristics vary from lift to lift during a shift. © 2015, Human Factors and Ergonomics Society.

Physical Activity in Physical Education: Are Longer Lessons Better?

PubMed Central

Smith, Nicole J.; Monnat, Shannon M.; Lounsbery, Monica A.F.

2015-01-01

BACKGROUND The purpose of this study was to compare physical activity (PA) outcomes in a sample of high school physical education (PE) lessons from schools that adopted traditional versus modified block schedule formats. METHODS We used the System for Observing Fitness Instruction Time (SOFIT) to conduct observations of 168 high school (HS) PE lessons delivered by 22 PE teachers in 4 schools. We used t-tests and multilevel models were used to explore variability in moderate PA and vigorous PA. RESULTS PA outcomes were significantly different between modified block and traditional schools. Students who attended traditional schools engaged in more vigorous PA in PE lessons. Modified block lessons lost more scheduled lesson time due to poor transition to and from the locker room. PA outcomes were positively associated with fitness and teacher promotion of PA and negatively associated with lost time, class size, management, and knowledge. CONCLUSIONS Though PE proponents widely advocate for more PE minutes, this study showed that greater time scheduled in PE does not necessarily result in more student accrual of MVPA minutes. PMID:25611935

Student Self-Efficacy in Introductory Project-Based Learning Courses

NASA Astrophysics Data System (ADS)

Pleiss, Geoffrey; Zastavker, Yevgeniya V.

2012-02-01

This study investigates first-year engineering students' self-efficacy in two introductory Project-Based Learning (PjBL) courses -- Physics (Mechanics) Laboratory and Engineering Design -- taught at a small technical institution. Twelve students participated in semi-structured open-ended interviews about their experiences in both courses. Analysis was performed using grounded theory. Results indicate that students had lower self-efficacy in Physics Lab than in Engineering Design. In Physics Lab, students reported high levels of faculty-supported scaffolding related to final project deliverables, which in turn established perceptions of an outcome-based course emphasis. Conversely, in Engineering Design, students observed high levels of scaffolding related to the intermediate project deliverables, highlighting process-centered aspects of the course. Our analyses indicate that this difference in student perceptions of course emphases -- resulting from the differences in scaffolding -- is a primary factor for the discrepancy in self-efficacy between Physics Lab and Engineering Design. Future work will examine how other variables (e.g., academic background, perception of community, gender) affect students' self-efficacy and perception of scaffolding in these PjBL courses.

Simultaneous Ultraviolet Line and Continuum Variability Studies in Seyfert 1 Galaxies and Quasars

NASA Astrophysics Data System (ADS)

Honnappa, Vijayakumar; Prabhakar, Vedavvathi

Simultaneous Ultraviolet Line and Continuum Variability Studies in Seyfert 1 Galaxies and Quasars Vijayakumar H. Doddamani*and P. Vedavathi Department of Physics, Bangalore University, Bangalore-560056, *Corresponding author:drvkdmani@gmail.com, Abstract The line and continuum flux variability is a hallmark phenomenon of Seyfert 1 galaxies and quasars. Large amplitude luminosity variability is observed in AGNs from x-rays through radio waves over a wide-ranging timescales from minutes to years. The combinations of high luminosity and short variability time scales suggests, that the power of AGN is produced by a phenomena more efficient in terms of energy release per unit mass than ordinary stellar processes. The basic structure of AGNs thus developed based on the variability studies consists of a central super massive black hole surrounded by an accretion disk or more generally optically thick plasma radiating brightly at UV and soft X-ray wavelengths. The variability studies have been important tools of understanding the physics of the central regions of AGNs, which in general cannot be resolved with the existing or planned ground and space telescopes. Therefore, we have undertaken a study of the simultaneous ultraviolet line and continuum flux variability studies in MRK501, ESOB113-IG45 (also called as Fairall 9), MRK1506, MRK1095 V*GQCOM, PG1211+143, MRK205, PG1226+023 (also known as 3C273), PG1351+640, MRK 1383, MRK876 and QSO2251-178 as these objects have been repeatedly observed by IUE satellite over several years.. It is observed that Fairall 9, MRK 1095 and 3C273 exhibit the large amplitude variability (» 30 times) over the observed timescale, which spans several years. The remaining nine objects exhibit small amplitude (» 5 times) variability over the long time scale of observations. The highest amplitude variability is observed in Lya with a least in the MgII line. The amplitude of variability decreases in the order of Lya, CIV and Mg II, lines. These results suggest that the BLR is spatially stratified into different regions from the central compact nuclear engine. Keywords: Active galaxies, Seyfert galaxies, Quasars, Line and continuum, Variability, Supermassive black hole

Development of a mathematical model of the human cardiovascular system: An educational perspective

NASA Astrophysics Data System (ADS)

Johnson, Bruce Allen

A mathematical model of the human cardiovascular system will be a useful educational tool in biological sciences and bioengineering classrooms. The goal of this project is to develop a mathematical model of the human cardiovascular system that responds appropriately to variations of significant physical variables. Model development is based on standard fluid statics and dynamics principles, pressure-volume characteristics of the cardiac cycle, and compliant behavior of blood vessels. Cardiac cycle phases provide the physical and logical model structure, and Boolean algebra links model sections. The model is implemented using VisSim, a highly intuitive and easily learned block diagram modeling software package. Comparisons of model predictions of key variables to published values suggest that the model reasonably approximates expected behavior of those variables. The model responds plausibly to variations of independent variables. Projected usefulness of the model as an educational tool is threefold: independent variables which determine heart function may be easily varied to observe cause and effect; the model is used in an interactive setting; and the relationship of governing equations to model behavior is readily viewable and intuitive. Future use of this model in classrooms may give a more reasonable indication of its value as an educational tool.* *This dissertation includes a CD that is multimedia (contains text and other applications that are not available in a printed format). The CD requires the following applications: CorelPhotoHouse, CorelWordPerfect, VisSinViewer (included on CD), Internet access.

Variability in the American Society of Anesthesiologists (ASA) Physical Status (PS) Classifcation Scale

DTIC Science & Technology

1999-10-01

instrument, and was deemed unsuitable because it was altered by several variables (patient condition, planned surgical procedure, experience and skill...index of anesthetic risk could be developed. Variables in addition to the patient physical status ( experience of the surgeon, anesthetist, and hospital...and other concurrent illnesses), but also by risk inherent to the specific surgery. Surgical risks include experience of the surgical team, the

2D VARIABLY SATURATED FLOWS: PHYSICAL SCALING AND BAYESIAN ESTIMATION

EPA Science Inventory

A novel dimensionless formulation for water flow in two-dimensional variably saturated media is presented. It shows that scaling physical systems requires conservation of the ratio between capillary forces and gravity forces. A direct result of this finding is that for two phys...

Neighborhood environment correlates of physical activity and sedentary behavior among Latino adults in Massachusetts.

PubMed

Silfee, Valerie J; Rosal, Milagros C; Sreedhara, Meera; Lora, Vilma; Lemon, Stephenie C

2016-09-13

U.S. Latinos experience high rates of cardio-metabolic diseases and have high rates of physical inactivity and sedentary behavior. Understanding the environmental factors associated with physical activity and sedentary behaviors among Latinos could inform future interventions. The purpose of this study is to explore the neighborhood environment correlates of physical activity and sedentary behavior in a sample of U.S. Latino adults. Cross-sectional study of 602 Latino adults in Lawrence, MA. Survey assessments of physical activity, sedentary behavior, and neighborhood environment were verbally administered. The neighborhood environment scale assessed violence, safety, aesthetic quality, walkability, availability of healthy foods, social cohesion, and activities with neighbors. After controlling forage, gender, education, body mass index (BMI), and smoking status, two variables were associated with the outcomes of interest. Living in more walkable neighborhoods was associated with an increased likelihood of engaging in adequate levels of physical activity (>150 min per week, as recommended by the American College of Sports Medicine (ACSM)) (OR = 1.403, p = .018); and greater frequency of activities with neighbors was associated with greater sedentary behavior (β = .072, p = .05). There were different neighborhood environment correlates of physical activity and sedentary behavior in this Latino community. Focusing on a greater understanding of the distinct social and physical environmental correlates of physical activity and sedentary behavior may provide important insights for reducing CVD risk and health disparities among Latinos.

Update of global TC simulations using a variable resolution non-hydrostatic model

NASA Astrophysics Data System (ADS)

Park, S. H.

2017-12-01

Using in a variable resolution meshes in MPAS during 2017 summer., Tropical cyclone (TC) forecasts are simulated. Two physics suite are tested to explore performance and bias of each physics suite for TC forecasting. A WRF physics suite is selected from experience on weather forecasting and CAM (Community Atmosphere Model) physics is taken from a AMIP type climate simulation. Based on the last year results from CAM5 physical parameterization package and comparing with WRF physics, we investigated a issue with intensity bias using updated version of CAM physics (CAM6). We also compared these results with coupled version of TC simulations. During this talk, TC structure will be compared specially around of boundary layer and investigate their relationship between TC intensity and different physics package.

A Bayesian network approach for modeling local failure in lung cancer

NASA Astrophysics Data System (ADS)

Oh, Jung Hun; Craft, Jeffrey; Lozi, Rawan Al; Vaidya, Manushka; Meng, Yifan; Deasy, Joseph O.; Bradley, Jeffrey D.; El Naqa, Issam

2011-03-01

Locally advanced non-small cell lung cancer (NSCLC) patients suffer from a high local failure rate following radiotherapy. Despite many efforts to develop new dose-volume models for early detection of tumor local failure, there was no reported significant improvement in their application prospectively. Based on recent studies of biomarker proteins' role in hypoxia and inflammation in predicting tumor response to radiotherapy, we hypothesize that combining physical and biological factors with a suitable framework could improve the overall prediction. To test this hypothesis, we propose a graphical Bayesian network framework for predicting local failure in lung cancer. The proposed approach was tested using two different datasets of locally advanced NSCLC patients treated with radiotherapy. The first dataset was collected retrospectively, which comprises clinical and dosimetric variables only. The second dataset was collected prospectively in which in addition to clinical and dosimetric information, blood was drawn from the patients at various time points to extract candidate biomarkers as well. Our preliminary results show that the proposed method can be used as an efficient method to develop predictive models of local failure in these patients and to interpret relationships among the different variables in the models. We also demonstrate the potential use of heterogeneous physical and biological variables to improve the model prediction. With the first dataset, we achieved better performance compared with competing Bayesian-based classifiers. With the second dataset, the combined model had a slightly higher performance compared to individual physical and biological models, with the biological variables making the largest contribution. Our preliminary results highlight the potential of the proposed integrated approach for predicting post-radiotherapy local failure in NSCLC patients.

Quality of life in relation to physical, psychosocial and socioeconomic conditions among reindeer-herding Sami.

PubMed

Daergo, Laila; Edin-Liljegren, Anette; Sjölander, Per

2008-02-01

To analyse different aspects of health-related quality of life factors among members of reindeer-herding families. Cross-sectional study based on data from a comprehensive survey. The health-related quality of life (SF-36) factors were analysed on 99 (56 men, 43 women) adult members of reindeer-herding families. Comparisons were made between the reindeer-herding family members and a Swedish reference population. Associations between mental and physical component summary measures and a number of sociodemographic, biomedical, physical, psychosocial and socio-economic variables were analysed with multivariate regression statistics. Men scored higher than women on physical and social function and vitality. The average scores on the subscales for the reindeer-herding family members were similar to those of the Swedish reference population, except for reindeer-herding men who scored higher on physical function and lower on bodily pain. For women, the quality of life was related to age, sense of coherence, lifestyle and behavioural variables, as well as to issues such as diseases among close relatives, social networks and the economy of their business. For men, it was mainly related to musculoskeletal pain conditions, age, sense of coherence and physical and psychosocial working conditions. Men and women of the reindeer-herding families need partly different conditions to enjoy a high quality of life. From the results, it might be predicted that poor somatic and psychosocial health, increased intrusion from exploiters on the grazing land and declining profit in reindeer husbandry constitute important threats to a good quality of life among members of reindeer-herding families.

Heart Rate and Cardiovascular Responses to Commercial Flights: Relationships with Physical Fitness.

PubMed

Oliveira-Silva, Iransé; Leicht, Anthony S; Moraes, Milton R; Simões, Herbert G; Del Rosso, Sebastián; Córdova, Cláudio; Boullosa, Daniel A

2016-01-01

The aim of this study was to examine the influence of physical fitness on cardiac autonomic control in passengers prior to, during and following commercial flights. Twenty-two, physically active men (36.4 ± 6.4 years) undertook assessments of physical fitness followed by recordings of 24-h heart rate (HR), heart rate variability (HRV), and blood pressure (BP) on a Control (no flight) and Experimental (flight) day. Recordings were analyzed using a two-way analysis of variance for repeated measures with relationships between variables examined via Pearson product-moment correlation coefficients. Compared to the Control day, 24-h HR was significantly greater (>7%) and HRV measures (5-39%) significantly lower on the Experimental day. During the 1-h flight, HR (24%), and BP (6%) were increased while measures of HRV (26-45%) were reduced. Absolute values of HRV during the Experimental day and relative changes in HRV measures (Control-Experimental) were significantly correlated with measures of aerobic fitness ( r = 0.43 to 0.51; -0.53 to -0.52) and body composition ( r = -0.63 to -0.43; 0.48-0.61). The current results demonstrated that short-term commercial flying significantly altered cardiovascular function including the reduction of parasympathetic modulations. Further, greater physical fitness and lower body fat composition were associated with greater cardiac autonomic control for passengers during flights. Enhanced physical fitness and leaner body composition may enable passengers to cope better with the cardiovascular stress and high allostatic load associated with air travel for enhanced passenger well-being.

Heart Rate and Cardiovascular Responses to Commercial Flights: Relationships with Physical Fitness

PubMed Central

Oliveira-Silva, Iransé; Leicht, Anthony S.; Moraes, Milton R.; Simões, Herbert G.; Del Rosso, Sebastián; Córdova, Cláudio; Boullosa, Daniel A.

2016-01-01

The aim of this study was to examine the influence of physical fitness on cardiac autonomic control in passengers prior to, during and following commercial flights. Twenty-two, physically active men (36.4 ± 6.4 years) undertook assessments of physical fitness followed by recordings of 24-h heart rate (HR), heart rate variability (HRV), and blood pressure (BP) on a Control (no flight) and Experimental (flight) day. Recordings were analyzed using a two-way analysis of variance for repeated measures with relationships between variables examined via Pearson product-moment correlation coefficients. Compared to the Control day, 24-h HR was significantly greater (>7%) and HRV measures (5–39%) significantly lower on the Experimental day. During the 1-h flight, HR (24%), and BP (6%) were increased while measures of HRV (26–45%) were reduced. Absolute values of HRV during the Experimental day and relative changes in HRV measures (Control-Experimental) were significantly correlated with measures of aerobic fitness (r = 0.43 to 0.51; −0.53 to −0.52) and body composition (r = −0.63 to −0.43; 0.48–0.61). The current results demonstrated that short-term commercial flying significantly altered cardiovascular function including the reduction of parasympathetic modulations. Further, greater physical fitness and lower body fat composition were associated with greater cardiac autonomic control for passengers during flights. Enhanced physical fitness and leaner body composition may enable passengers to cope better with the cardiovascular stress and high allostatic load associated with air travel for enhanced passenger well-being. PMID:28082914

Potential Influences on Mathematical Difficulties in Children and Adolescents with Neurofibromatosis, Type 1

ERIC Educational Resources Information Center

Moore, Bartlett D.

2009-01-01

Neurofibromatosis, type 1 (NF-1) is a common genetic disorder affecting 1 in 3,500-4,000 individuals in the world. Mutations of the NF-1 gene produce a myriad of physical, medical, and psychological manifestations. Although there is a very high degree of variability in the manifestations between individuals with NF-1, the majority of children and…

Starspot detection and properties

NASA Astrophysics Data System (ADS)

Savanov, I. S.

2013-07-01

I review the currently available techniques for the starspots detection including the one-dimensional spot modelling of photometric light curves. Special attention will be paid to the modelling of photospheric activity based on the high-precision light curves obtained with space missions MOST, CoRoT, and Kepler. Physical spot parameters (temperature, sizes and variability time scales including short-term activity cycles) are discussed.

Evaluation of the reference unit method for herbaceous biomass estimation in native grasslands of southwestern South Dakota

Treesearch

Eric D. Boyda

2013-01-01

The high costs associated with physically harvesting plant biomass may prevent sufficient data collection, which is necessary to account for the natural variability of vegetation at a landscape scale. A biomass estimation technique was previously developed using representative samples or "reference units", which eliminated the need to harvest biomass from all...

Changes in Physical Activity and Psychological Variables Following a Web-Based Motivational Interviewing Intervention: Pilot Study.

PubMed

Karnes, Sasha L; Meyer, Barbara B; Berger, Lisa M; Brondino, Michael J

2015-10-29

Web-based interventions for enhancing physical activity participation are in demand for application in health care settings. Recent research suggests Web-based interventions that are based on motivational interviewing are effective to increase physical activity. It is unclear whether motivational interviewing can influence targeted psychological variables such as perceived readiness, willingness, and ability to participate in physical activity. The aims of this study were to determine whether there were changes in physical activity and psychological variables associated with readiness, willingness, and perceived ability to participate in physical activity following completion of a novel Web-based intervention. The goal of the motivational interviewing-based intervention was to increase physical activity. Twenty-three underactive or inactive urban dwelling adults were recruited at a medical office for participation in a 4-session Web-based intervention lasting approximately 15 minutes per week. Sessions were based on principles of motivational interviewing. Assessment of physical activity was conducted using pedometers immediately prior to intervention participation (pre) and immediately post intervention (post1). Self-report assessments of physical activity and psychological variables were conducted using online surveys at pre, post1, and again at one month following intervention participation (post2). Comparisons of pre and post1 pedometer recordings revealed significant increases in steps per day (t22=2.09, P=.049). There were also significant changes in total physical activity energy expenditure per week (χ(2) 2=8.4, P=.02) and in moderate intensity physical activity energy expenditure per week (χ(2) 2=13.9, P<.001) over time following participation in the Web-based intervention. Significant changes in psychological variables following participation in the Web-based intervention included: (1) change in stage classification over time (χ(2) 2=21.5, P<.001), where the percentage of participants classified in the action or maintenance stages of change in physical activity increased over time (pre=25% [6/24], post1=71% [17/24], post2=68% [15/22]); (2) decreases in self-reported decisional balance cons (F2,42=12.76, P<.001); (3) increases in self-reported decisional balance pros (F2,42=16.19, P<.001); (4) increases in physical activity enjoyment (F2,20=3.85, P=.04); and (5) increases in self-efficacy (F2,42=3.30, P=.047). The Web-based intervention piloted in this study shows preliminary promise as a tool to promote physical activity in health care settings. Additional research is needed to test the effectiveness of motivational interviewing compared to a control condition and to refine content by considering mediation by psychological variables in a larger sample.

Association of socioeconomic, school-related and family factors and physical activity and sedentary behaviour among adolescents: multilevel analysis of the PRALIMAP trial inclusion data.

PubMed

Langlois, Johanne; Omorou, Abdou Y; Vuillemin, Anne; Briançon, Serge; Lecomte, Edith

2017-02-08

Social differences among adolescents in physical activity and sedentary behaviour have been identified but are not well explained. The current study aimed to identify socioeconomic, family and school-related associated factors with physical activity and sedentary behaviour among high-school adolescents. This was a cross-sectional analysis of T0 physical activity and sedentary behaviour of 2523 students 14 - 18 years old recruited for the PRALIMAP trial from 24 French state-run high schools. Data were collected by self-administered questionnaire at the start of grade 10. Adolescents completed the International Physical Activity Questionnaire for physical activity and sedentary behaviour and an ad hoc questionnaire for active commuting and sport participation. Statistical analyses involved linear and logistic regressions. Socioeconomic, family or school variables were associated with levels of physical activity and sedentary behaviour for both boys and girls, but no factor, except perceived parental physical activity level, was associated with total energy expenditure (total physical activity) for either gender. Adolescents with privileged and less privileged socioeconomic status reported the same total amount of energy expenditure. Total physical activity score alone is not sufficient to assess the physical activity of adolescents. These findings may have implications for better understanding of social inequalities in this context and recommendations to prevent overweight. This trial is registered at ClinicalTrials.gov ( NCT00814554 ). The date of registration: 23 December 2008. Registration was not required at the time of the start of PRALIMAP for public health and prevention programmes and trials.

Individual differences in cardiac vagal tone are associated with differential neural responses to facial expressions at different spatial frequencies: an ERP and sLORETA study.

PubMed

Park, Gewnhi; Moon, Eunok; Kim, Do-Won; Lee, Seung-Hwan

2012-12-01

A previous study has shown that greater cardiac vagal tone, reflecting effective self-regulatory capacity, was correlated with superior visual discrimination of fearful faces at high spatial frequency Park et al. (Biological Psychology 90:171-178, 2012b). The present study investigated whether individual differences in cardiac vagal tone (indexed by heart rate variability) were associated with different event-related brain potentials (ERPs) in response to fearful and neutral faces. Thirty-six healthy participants discriminated the emotion of fearful and neutral faces at broad, high, and low spatial frequencies, while ERPs were recorded. Participants with low resting heart rate variability-characterized by poor functioning of regulatory systems-exhibited significantly greater N200 activity in response to fearful faces at low spatial frequency and greater LPP responses to neutral faces at high spatial frequency. Source analyses-estimated by standardized low-resolution brain electromagnetic tomography (sLORETA)-tended to show that participants with low resting heart rate variability exhibited increased source activity in visual areas, such as the cuneus and the middle occipital gyrus, as compared with participants with high resting heart rate variability. The hyperactive neural activity associated with low cardiac vagal tone may account for hypervigilant response patterns and emotional dysregulation, which heightens the risk of developing physical and emotional problems.