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Sample records for physical predictor variables

  1. Variability in Physical Activity Assessed with Accelerometer Is an Independent Predictor of Mortality in CHF Patients

    PubMed Central

    Melin, Michael; Hagerman, Inger; Gonon, Adrian; Gustafsson, Thomas; Rullman, Eric

    2016-01-01

    Aims Patients with heart failure often display a distinct pattern of walking characterized by short step-length and frequent short pauses. In the current study we sought to explore if qualitative aspects of movement have any additive value to established factors to predict all-cause mortality in patients with advanced heart failure. Methods and results 60 patients with advanced heart failure (NYHA III, peak VO2 <20 ml/kg and LVEF <35%) underwent symptom-limited CPX, echocardiography and routine chemistry. Physical activity was assessed using an accelerometer worn attached to the waist during waking hours for 7 consecutive days. The heart-failure survival score (HFSS) was calculated for each patient. All accelerometer-derived variables were analyzed with regard to all-cause mortality and added to a baseline model utilizing HFSS scores. HFSS score was significantly associated with the incidence of death (P<0.001; c-index 0.71; CI, 0.67–0.73). The addition of peak skewness to the HFSS model significantly improved the predictive ability with an increase in c-index to 0.74 (CI, 0.69–0.78), likelihood ratio P<0.02, establishing skewness as a predictor of increased event rates when accounting for baseline risk. Conclusion The feature skewness, a measure of asymmetry in the intensity level of periods of high physical activity, was identified to be predictive of all-cause mortality independent of the established prognostic model–HFSS and peak VO2. The findings from the present study emphasize the use of accelerometer analysis in clinical practice to make more accurate prognoses in addition to extract features of physical activity relevant to functional classification. PMID:27054323

  2. Estimating Interaction Effects With Incomplete Predictor Variables

    PubMed Central

    Enders, Craig K.; Baraldi, Amanda N.; Cham, Heining

    2014-01-01

    The existing missing data literature does not provide a clear prescription for estimating interaction effects with missing data, particularly when the interaction involves a pair of continuous variables. In this article, we describe maximum likelihood and multiple imputation procedures for this common analysis problem. We outline 3 latent variable model specifications for interaction analyses with missing data. These models apply procedures from the latent variable interaction literature to analyses with a single indicator per construct (e.g., a regression analysis with scale scores). We also discuss multiple imputation for interaction effects, emphasizing an approach that applies standard imputation procedures to the product of 2 raw score predictors. We thoroughly describe the process of probing interaction effects with maximum likelihood and multiple imputation. For both missing data handling techniques, we outline centering and transformation strategies that researchers can implement in popular software packages, and we use a series of real data analyses to illustrate these methods. Finally, we use computer simulations to evaluate the performance of the proposed techniques. PMID:24707955

  3. Predictor Variables in Computer Assisted Language Learning.

    ERIC Educational Resources Information Center

    Clark, Stephen K.

    1992-01-01

    Investigates several instruments measuring intelligence and prior conceptual knowledge/achievement to determine how well they predict outcomes in computer assisted language learning. Concludes that a non-verbal intelligence test was a significant predictor, but that prior conceptual knowledge of course content was low. Level of prior achievement…

  4. Identifying predictors of physics item difficulty: A linear regression approach

    NASA Astrophysics Data System (ADS)

    Mesic, Vanes; Muratovic, Hasnija

    2011-06-01

    Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary difficult and very easy items. Knowing the factors that influence physics item difficulty makes it possible to model the item difficulty even before the first pilot study is conducted. Thus, by identifying predictors of physics item difficulty, we can improve the test-design process. Furthermore, we get additional qualitative feedback regarding the basic aspects of student cognitive achievement in physics that are directly responsible for the obtained, quantitative test results. In this study, we conducted a secondary analysis of data that came from two large-scale assessments of student physics achievement at the end of compulsory education in Bosnia and Herzegovina. Foremost, we explored the concept of “physics competence” and performed a content analysis of 123 physics items that were included within the above-mentioned assessments. Thereafter, an item database was created. Items were described by variables which reflect some basic cognitive aspects of physics competence. For each of the assessments, Rasch item difficulties were calculated in separate analyses. In order to make the item difficulties from different assessments comparable, a virtual test equating procedure had to be implemented. Finally, a regression model of physics item difficulty was created. It has been shown that 61.2% of item difficulty variance can be explained by factors which reflect the automaticity, complexity, and modality of the knowledge structure that is relevant for generating the most probable correct solution, as well as by the divergence of required thinking and interference effects between intuitive and formal physics knowledge

  5. Variables Affecting Physics Achievement

    ERIC Educational Resources Information Center

    Lawrenz, Frances; Wood, Nathan B.; Kirchhoff, Allison; Kim, Nam Keol; Eisenkraft, Arthur

    2009-01-01

    Much research has focused on student views about physics concepts, with an emphasis on the identification of alternative conceptions, and how curricula and professional development may ameliorate the situation. However, there has been little work on determining the extent of, and in separating, the student and teacher/classroom level variables…

  6. Neo-piagetian predictors of achievement in physical science

    NASA Astrophysics Data System (ADS)

    Roth, Wolff-Michael

    This article examines the predictive value of the cognitive variables of developmental level, mental capacity, cognitive style, short-term storage space, and numerical inductive reasoning for student achievement in college science. Achievement was analyzed for each of the categories of pure recall, computational, complex items, and total score of a midterm exam as well as for the composite score on a final exam. The sample for this study consisted of a class of 32 nonscience majors enrolled in Physical Science I at the University of Southern Mississippi. The results showed that developmental level was the single best predictor of achievement. Short-term storage space and mental capacity were significant predictors of achievement for computational and complex items, but, as expected from theoretical considerations, not for pure recall items. The degree of field dependence did not well predict performance on pure recall or computational items. The results also indicate that mental capacity and field dependence do not contribute significantly to the variance if developmental level is held constant. The pattern of the predictive power of numerical inductive reasoning parallels, in magnitude, that of mental capacity. The results of this study and its implications indicate that the construct of short-term storage space has great potential to guide classroom practice and the development of instructional materials. A strategy is outlined that would guide curriculum planners and classroom teachers in the development of materials which would allow students to develop complex problem-solving behaviors.

  7. How Variables Uncorrelated with the Dependent Variable Can Actually Make Excellent Predictors: The Important Suppressor Variable Case.

    ERIC Educational Resources Information Center

    Woolley, Kristin K.

    Many researchers are unfamiliar with suppressor variables and how they operate in multiple regression analyses. This paper describes the role suppressor variables play in a multiple regression model and provides practical examples that explain how they can change research results. A variable that when added as another predictor increases the total…

  8. 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

    , 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

  9. Predictor variables for forward scapular posture including posterior shoulder tightness.

    PubMed

    Lee, Ji-Hyun; Cynn, Heon-seock; Yi, Chung-Hwi; Kwon, Oh-yun; Yoon, Tae-Lim

    2015-04-01

    The purpose of this study was (1) to determine the relationships between the degree of forward scapular posture and the pectoralis minor index, the strength of the serratus anterior, the thoracic spine angle, and posterior shoulder tightness, and (2) to identify predictors of forward scapular posture, including posterior shoulder tightness. The study recruited eighteen subjects with forward scapular posture and objectively measured the acromion distance, the pectoralis minor index, and the strength of the serratus anterior muscle of each participant. The amount of glenohumeral horizontal adduction and internal rotation were evaluated to measure posterior shoulder tightness. There were high intra-rater reliabilities in all measurements. The measurement results showed a statistically strong negative correlation between the degree of forward scapular posture and the pectoralis minor index. They also revealed a moderate positive correlation between the degree of forward scapular posture and the thoracic spine angle and a moderate negative relationship between the degree of forward scapular posture and the amount of the glenohumeral horizontal adduction. A multiple regression analysis indicated that a total multiple regression model explained 93% of the amount of forward scapular posture. All predictor variables, including posterior shoulder tightness, should be considered while assessing, managing, and preventing forward scapular posture. PMID:25892380

  10. Optimal Selection of Predictor Variables in Statistical Downscaling Models of Precipitation

    NASA Astrophysics Data System (ADS)

    Goly, A.; Teegavarapu, R. S. V.

    2014-12-01

    Statistical downscaling models developed for precipitation rely heavily on predictors chosen and on accurate relationships between regional scale predictand and GCM-scale predictor for providing future precipitation projections at different spatial and temporal scales. This study provides two new screening methods for selection of predictor variables for use in downscaling methods based on predictand-predictors relationships. Methods to characterize predictand-predictors relationships via rigid and flexible functional relationships using mixed integer nonlinear programming (MINLP) model with binary variables and artificial neural network (ANN) models respectively are developed and evaluated in this study. In addition to these two methods, a stepwise regression (SWR) and two models that do not use any pre-screening of variables are also evaluated. A two-step process is used to downscale precipitation data with optimal selection of predictors and using them in a statistical downscaling model based on support vector machine (SVM) approach. Experiments with the proposed two new methods and three additional methods based on correlation between predictors and predictand and the other based on principal component analysis are evaluated in this study. Results suggest that optimal selection of variables using MINLP albeit with linear relationship and ANN method provided improved performance and error measures compared to two other models that did not use these methods for screening the variables. Of all the three screening methods tested in this study, SWR method selected the least number of variables and also ranked lowest based on several performance measures.

  11. Parental Predictors of Physical Inactivity in Spanish Adolescents

    PubMed Central

    Sanz-Arazuri, Eva; Ponce-de-León-Elizondo, Ana; Valdemoros-San-Emeterio, María Ángeles

    2012-01-01

    The purpose of this study was to determine some parental predictors of physical inactivity in Spanish adolescents. The sample comprised 1,978 children, aged between 12 and 16 years. A quantitative and qualitative technical triangulation was employed. The study analyzed data of the parents' educational level, the importance they grant to physical-sport activities, and their physical-sport practice. Quantitative technique: a questionnaire (MACOFYD) was used to collect the data. Descriptive, bivariate, and multinomial regression analyses were employed. Statistical significance was set at p < 0.05. Qualitative technique: four discussion groups were conducted, consisting of parents, physical education teachers, teachers of other subjects, and children aged between 12 and 16 years. The results indicated that adolescents are four times more likely to be physically inactive if their parents have never exercised (odds ratio [OR] = 4.065, and = 3.487, for the fathers and mothers, respectively, p < 0.05). When parents grant “some” or “much” importance to physical-sport practice, adolescents are less likely to be physically inactive (OR = 0.185 and 0.118 respectively, p < 0.01). No significant correlation was found between adolescents' physical-sport activity and parents' educational level. However, young people reproach their parents because they emphasize academic goals more than physical-sport practice-an observation that teachers also confirm. Young people perceive their parents as being the education agents with the greatest influence over their inactive lifestyles. Many parents are unaware of their influence and, therefore, do not take responsibility, declaring that the teachers' influence is greater. Key points Parental factors significantly affect adolescent physical inactivity. Parents' physical inactivity is among the most important factors. Statistically significant results were found for gender. Being female tripled the likelihood of being sedentary. The

  12. Cognitive and Motivational Variables as Predictors of Academic Performance Among Disadvantaged College Students

    ERIC Educational Resources Information Center

    Trachtman, Joan P.

    1975-01-01

    Validity of selected cognitive and affective variables as predictors of academic success among disadvantaged minority college students was analyzed via multiple regression. The best combination of predictors was reading, attitude toward authority, internality-externality (selected items), and dogmatism, which together accounted for approximately…

  13. Short-term variability and predictors of urinary pentachlorophenol levels in Ohio preschool children

    EPA Science Inventory

    Pentachlorophenol (PCP) is a persistent and ubiquitous environmental contaminant. No published data exist on the temporal variability or important predictors of urinary PCP concentrations in young children. In this further analysis of study data, we have examined the associations...

  14. Predictor and Performance Variables in a Performance Based Education Course.

    ERIC Educational Resources Information Center

    Hughes, Thomas M.; Douzenis, Cordelia

    Students enrolled in classes which stressed learning theory and human development served as subjects in an investigation of the predictive power of observation scores compared to more traditional predictors such as grade point average and ACT scores. A stepwise discriminant analysis was employed, using the BMDP7B program on the Sperry 1100 Univac,…

  15. Community level predictors of physical activity among women in the preconception period.

    PubMed

    Vamos, Cheryl A; Sun, Haichun; Flory, Sara B; DeBate, Rita; Daley, Ellen M; Thompson, Erika; Bleck, Jennifer; Merrell, Laura

    2015-07-01

    Although physical activity is a key behavior targeted during the preconception period given its significant impact on pregnancy/birth outcomes and psychological well-being, few women meet national guidelines. While intrapersonal factors influencing physical activity among this population have been studied, community factors remain unexplored. The objective of this study was to examine community level predictors of physical activity among preconception women. Data from Add Health were limited to women (Wave III; age 18-28; n = 7,596) and excluded respondents who were pregnant, physically disabled, and missing data. The outcome variable was ≥5 instances of moderate-vigorous physical activity (MVPA) in 1 week. Community predictor variables included neighborhood-level structural and social determinants (e.g., socio-demographic composition; landscape diversity; urbanization; access to resources; crime; vehicle availability). Multilevel logistic regression modeling was used to estimate the odds of engaging in ≥5 instances of MVPA. Few women (26 %) reported ≥5 instances of MVPA in 1 week. Adjusted multilevel analysis revealed women in the preconception period were more likely to report high MVPA when living in communities with larger population densities (OR 1.34, 95 % CI 1.02-1.77) and median household income greater than $50,000 (OR 1.33, 95 % CI 1.06-1.66). Additionally, a significant inverse trend was found between high MVPA and proportion of the community without a high school diploma. Findings suggest that neighborhood composition may have an impact on preconception physical activity status. Implications include increased efforts targeting community conditions for facilitating physical activity; ultimately, improving health among women and subsequent offspring. PMID:25636646

  16. Levels of physical activity and predictors of mortality in COPD*

    PubMed Central

    Nyssen, Samantha Maria; dos Santos, Júlia Gianjoppe; Barusso, Marina Sallum; de Oliveira, Antônio Delfino; Lorenzo, Valéria Amorim Pires Di; Jamami, Mauricio

    2013-01-01

    OBJECTIVE: To compare the Body mass index, airway Obstruction, Dyspnea, and Exercise capacity (BODE) index scores and its individual components between COPD patients with and without severe physical inactivity, as well as to correlate the number of steps/day with scores of physical activity questionnaires, age, and the BODE index (including its components). METHODS: We included 30 patients, who were evaluated for body composition, pulmonary function (FEV1), perception of dyspnea (modified Medical Research Council scale), and exercise capacity (six-minute walk distance [6MWD]). The patients also completed the International Physical Activity Questionnaire (IPAQ), short version, and the modified Baecke questionnaire (mBQ). The level of physical activity was assessed by the number of steps/day (as determined by pedometer), using the cut-off of 4,580 steps/day to form two groups: no severe physical inactivity (SPI−) and severe physical inactivity (SPI+). We used the Mann-Whitney test or t-test, as well as Pearson's or Spearman's correlation tests, in the statistical analysis. RESULTS: In comparison with the SPI− group, the SPI+ group showed more advanced age, higher mBQ scores (leisure domain), lower 6MWD (in m and % of predicted), and lower IPAQ scores (metabolic equivalent-walk/week domain and total). The IPAQ scores showed weak correlations with steps/day (r = 0.399), age (r = −0.459), and 6MWD-in m (r = 0.446) and in % of predicted (r = 0.422). CONCLUSIONS: In our sample, the cut-off of 4,580 steps/day was not sensitive enough to identify differences between the groups when compared with the predictors of mortality. The IPAQ, short version score correlated with steps/day. PMID:24473759

  17. Predictors of Heavy Stethoscope Contamination Following a Physical Examination.

    PubMed

    Tschopp, Clément; Schneider, Alexis; Longtin, Yves; Renzi, Gesuele; Schrenzel, Jacques; Pittet, Didier

    2016-06-01

    BACKGROUND The degree of bacterial contamination of stethoscopes can vary significantly following a physical examination. OBJECTIVE To conduct a prospective study to investigate the impact of various environmental and patient characteristics on stethoscope contamination. METHODS Following a standardized examination, the levels of bacterial contamination of 4 regions of the physicians' hands and 2 sections of the stethoscopes, and the presence of different pathogenic bacteria, were assessed. Predictors of heavy stethoscope contamination were identified through multivariate logistic regression. RESULTS In total, 392 surfaces were sampled following examination of 56 patients. The microorganisms most frequently recovered from hands and stethoscopes were Enterococcus spp. (29% and 20%, respectively) and Enterobacteriaceae (16% and 7%, respectively). Staphylococcus aureus (either methicillin susceptible or resistant), extended-spectrum β-lactamase-producing Enterobacteriaceae, and Acinetobacter baumannii were recovered from 4%-9% of the samples from either hands or stethoscopes. There was a correlation between the likelihood of recovering these pathogens from the stethoscopes vs from the physicians' hands (ρ=0.79; P=.04). The level of patient's skin contamination was an independent predictor of contamination of the stethoscope diaphragm (adjusted odds ratio [aOR], 1.001; P=.007) and tube (aOR, 1.001; P=.003). Male sex (aOR, 28.24; P=.01) and reception of a bed bath (aOR, 7.52; P=.048) were also independently associated with heavy tube contamination. CONCLUSIONS Stethoscope contamination following a single physical examination is not negligible and is associated with the level of contamination of the patient's skin. Prevention of pathogen dissemination is needed. Infect Control Hosp Epidemiol 2016;37:673-679. PMID:27198604

  18. Who will increase their physical activity? Predictors of change in objectively measured physical activity over 12 months in the ProActive cohort

    PubMed Central

    2010-01-01

    Background The aim was to identify predictors of change in objectively measured physical activity over 12 months in the ProActive cohort to improve understanding of factors influencing change in physical activity. Methods ProActive is a physical activity promotion trial that took place in Eastern England (1999-2004). 365 offspring of people with type 2 diabetes underwent measurement of physical activity energy expenditure (PAEE) using heart rate monitoring, fitness, and anthropometric and biochemical status at baseline and 1 year (n = 321). Linear regression was used to quantify the associations between baseline demographic, clinical, psychosocial and behavioural variables and change in PAEE over 12 months. This study is registered as ISRCTN61323766. Results ProActive participants significantly increased their PAEE by 0.6 kj/min (SD 4.2, p = 0.006) over one year, the equivalent of around 20 minutes brisk walking/day. Male sex and higher fitness at baseline predicted increase in PAEE. No significant associations were found for any other variables. Very few baseline demographic, clinical, psychosocial and behavioural predictors were associated with change in objectively measured physical activity. Conclusions Traditional baseline determinants of self-reported physical activity targeted by behavioural interventions may be relatively weak predictors of change in objectively measured physical activity. Further research is needed to improve our understanding of factors influencing change in physical activity to inform the development and targeting of interventions. PMID:20433700

  19. a Latent Variable Path Analysis Model of Secondary Physics Enrollments in New York State.

    NASA Astrophysics Data System (ADS)

    Sobolewski, Stanley John

    The Percentage of Enrollment in Physics (PEP) at the secondary level nationally has been approximately 20% for the past few decades. For a more scientifically literate citizenry as well as specialists to continue scientific research and development, it is desirable that more students enroll in physics. Some of the predictor variables for physics enrollment and physics achievement that have been identified previously includes a community's socioeconomic status, the availability of physics, the sex of the student, the curriculum, as well as teacher and student data. This study isolated and identified predictor variables for PEP of secondary schools in New York. Data gathered by the State Education Department for the 1990-1991 school year was used. The source of this data included surveys completed by teachers and administrators on student characteristics and school facilities. A data analysis similar to that done by Bryant (1974) was conducted to determine if the relationships between a set of predictor variables related to physics enrollment had changed in the past 20 years. Variables which were isolated included: community, facilities, teacher experience, number of type of science courses, school size and school science facilities. When these variables were isolated, latent variable path diagrams were proposed and verified by the Linear Structural Relations computer modeling program (LISREL). These diagrams differed from those developed by Bryant in that there were more manifest variables used which included achievement scores in the form of Regents exam results. Two criterion variables were used, percentage of students enrolled in physics (PEP) and percent of students enrolled passing the Regents physics exam (PPP). The first model treated school and community level variables as exogenous while the second model treated only the community level variables as exogenous. The goodness of fit indices for the models was 0.77 for the first model and 0.83 for the second

  20. Demographic and Organizational Variables as Predictors of Teacher Attrition

    ERIC Educational Resources Information Center

    Watkins, Leah Rice

    2013-01-01

    The purpose of this study was to examine the predictive capacity of specific demographic and organizational variables upon teacher attrition from the profession. The study examined the possibility of predicting attrition of teachers based upon these variables. Furthermore, the study attempted to create a profile of the most likely teachers to…

  1. Physical Activity Enjoyment and Self-Efficacy As Predictors of Cancer Patients' Physical Activity Level

    PubMed Central

    Ungar, Nadine; Wiskemann, Joachim; Sieverding, Monika

    2016-01-01

    Background: Physical activity (PA) can support cancer patients during medical treatment by reducing side-effects and increasing quality of life. However, PA levels mostly decline after diagnosis. Which factors can explain if patients are able to remain or even increase their PA level? Self-efficacy is an important cognitive factor that has been linked to cancer patients' PA across many studies. In contrast, affective factors such as PA enjoyment have rarely been examined. We compare the influence of self-efficacy and PA enjoyment on cancer patients' PA levels after completion of an exercise or stress-management intervention. Methods: Outpatient cancer patients [N = 72; 54% female; M = 56 years, SD = 12.34; most with breast or colon cancer (34%, 15%)] were enrolled in the MOTIVACTION study, a 4-week intervention (1 h counseling followed by weekly phone calls), with pre-test (T1), post-test (T2), and a 10-week follow-up (T3). Participants were randomized to either an exercise intervention (emphasizing self-regulatory strategies for behavior change) or to a stress management intervention (coping and relaxation techniques). Sixty-seven patients remained in the study and completed the SQUASH assessment of PA, a measure of maintenance self-efficacy (7 items, Cronbach's α = 0.88) and PA enjoyment (2 items, Cronbach's α = 0.89). Regression analyses were calculated with PA level (at T2 and T3) as dependent variable and relative weight analyses were conducted. The study was registered at clinicalTrials.gov (unique identifier:NCT01576107; URL: https://clinicaltrials.gov/ct2/show/NCT01576107?term=motivaction&rank=1). Results: Baseline self-efficacy and change in PA enjoyment significantly predicted cancer patients' PA level at T2 adjusting for baseline PA and type of intervention. Relative weight (RW) analysis revealed that PA enjoyment (baseline and change together) explained 34.3% of the dependent variable, self-efficacy (baseline and change) explained 38.4%. At follow

  2. An Examination of Predictor Variables for Problematic Internet Use

    ERIC Educational Resources Information Center

    Bulut Serin, Nerguz

    2011-01-01

    This study examines problematic Internet use among university students in terms of gender, while also gauging the impact of personality traits, life satisfaction and loneliness variables on problematic Internet use. A total of 411 university students studying Education in North Cyprus participated in the study. The participants were selected using…

  3. Is the Authoritarian Trait in Mental Health Workers a Significant Predictor Variable of Patient Assault?

    ERIC Educational Resources Information Center

    Safian-Rush, Donna

    Mental health workers may be assaulted by their violent patients. A study was conducted to examine one predictor variable of aggressive behavior in patients. It was hypothesized that authoritarian traits in the mental health worker could result in more assaults against the mental health worker by patients. Participants (N=32) were mental health…

  4. Student-Related Variables as Predictors of Academic Achievement among Some Undergraduate Psychology Students in Barbados

    ERIC Educational Resources Information Center

    Fayombo, Grace Adebisi

    2011-01-01

    This study examined some student-related variables (interest in higher education, psychological resilience and study habit) as predictors of academic achievement among 131 (M (mean) = 28.17, SD (standard deviation) = 1.61) first year psychology students in the Introduction to Developmental Psychology class in UWI (The University of the West…

  5. Class Placement and Academic and Behavioral Variables as Predictors of Graduation for Students with Disabilities

    ERIC Educational Resources Information Center

    Gonzalez, Linda; Cramer, Elizabeth

    2013-01-01

    This study investigated the impact of a range of variables as predictors of graduation potential for students with Specific Learning Disabilities (SLD) or Emotional Behavioral Disorders (EBD) within a large urban school district. These factors included the following characteristics and elements: (a) primary exceptionality, (b) gender, (c)…

  6. Symptom burden, palliative care need and predictors of physical and psychological discomfort in two UK hospitals

    PubMed Central

    2013-01-01

    Background The requirement to meet the palliative needs of acute hospital populations has grown in recent years. With increasing numbers of frail older people needing hospital care as a result of both malignant and non-malignant conditions, emphasis is being placed upon understanding the physical, psychological and social burdens experienced by patients. This study explores the extent of burden in two large UK hospitals, focusing upon those patients who meet palliative care criteria. Furthermore, the paper explores the use of palliative services and identifies the most significant clinical diagnostic and demographic factors which determine physical and psychological burden. Methods Two hospital surveys were undertaken to identify burden using the Sheffield Profile for Assessment and Referral to Care (SPARC). The Gold Standards Framework (GSF) is used to identify those patients meeting palliative care criteria. Participants were identified as being in-patients during a two-week data collection phase for each site. Data was gathered using face-to-face interviews or self-completion by patients or a proxy. Descriptive analyses highlight prevalence and use of palliative care provision. Binary logistic regression assesses clinical diagnostic predictor variables of physical and psychological burden. Results The sample consisted of 514 patients and elevated physical, psychological and social burden is identified amongst those meeting palliative care criteria (n = 185). Tiredness (34.6%), pain (31.1%), weakness (28.8%) and psychological discomfort (low mood 19.9%; anxiety 16.1%) are noted as being prevalent. A small number of these participants accessed Specialist Palliative Care (8.2%). Dementia was identified as a predictor of physical (OR 3.94; p < .05) and psychological burden (OR 2.88; p < .05), being female was a predictor of psychological burden (OR 2.00; p < .05). Conclusion The paper highlights elevated levels of burden experienced by patients with

  7. Assessment of CMIP5 GCM daily predictor variables for statistical downscaling

    NASA Astrophysics Data System (ADS)

    Mpelasoka, F. S.; Charles, S.; Chiew, F. H.; Fu, G.; Beecham, S.

    2012-04-01

    Assessment of CMIP5 GCM daily predictor variables for statistical downscaling To support adaptation to climate change in the water resource sector in South Australia, downscaled climate projections are being constructed within the Goyder Institute for Water Research - a 5-year multi-million dollar collaborative research partnership between the Government of South Australia, CSIRO and the university sector. Statistical downscaling is a robust approach providing a link between observed (re-analysis) large-scale atmospheric variables (predictors) and local or regional surface climate variables such as daily station rainfall. When applied to outputs of Global Climate Models (GCMs), the credibility of statistically downscaled future projections is dependent on the ability of GCMs to reproduce the re-analysis data statistics for the current climate. The main objective of this study is thus to assess daily predictor variables simulated by phase Five of Coupled Model Inter-comparison Project (CMIP5) GCMs, while acknowledging that an optimal measure of overall GCM performance does not exist and the usefulness of any assessment approach varies with the intended application. Here we assess GCMs by comparing cumulative probability density functions of predictor variables against the re-analysis data using the Kolmogorov test metric. Historical daily data simulations from 12 GCMs (BCC-csm1, CanESM2, CSIRO-Mk3.6.0, GFDL-ESM2M, HadGEM2-ES, IPSL-CM5A-LR, IPSL-CM5A-MR, MIROC4h, MIROC-ESM-CHEM, MPI-ESM-LR, MRI-CGCM3, and NorESM1-M) for the period 1961-2005 are used. The variables assessed include specific/relative humidity, winds, geopotential heights at different atmospheric levels and sea-level pressure over the Australian region (7-45oS, 100-160oE). We present a summary of results for the South Australia region quantifying the ability of these GCMs in reproducing the mean state and the relative frequency of extremes for these predictors. The complexity and challenges in GCM

  8. Predictors of physical inactivity among elderly malaysians: recommendations for policy planning.

    PubMed

    Kaur, Jasvindar; Kaur, Gurpreet; Ho, Bee Kiau; Yao, Weng Keong; Salleh, Mohmad; Lim, Kuang Hock

    2015-04-01

    Physical inactivity is the fourth leading risk factor for global mortality. Regular moderate-intensity physical activity has significant benefits for health. To determine the socioeconomic predictors of physical inactivity among elderly Malaysian population. A nationwide community-based survey was conducted among 4831 respondents aged ≥60 years with a face-to-face questionnaire. The prevalence of physical inactivity among the elderly was 88.0%, highest in respondents aged older than 80 years (95.4%), females (90.1%), other Bumiputra (92.2%), earning household income less than RM1000 (87.9%), and residing in urban locality (88.4%). In the multivariate model, the predictors of physical inactivity were only sex, ethnicity, locality, and age group (adjusted odds ratio = 1.3-3.6). The predictors of physical inactivity can identify the risk factors to develop policies that will reduce the public health burden of noncommunicable diseases. PMID:24425796

  9. Physical characteristics of Eurasian winter temperature variability

    NASA Astrophysics Data System (ADS)

    Kim, Kwang-Yul; Son, Seok-Woo

    2016-04-01

    Despite the on-going global warming, recent winters in Eurasian mid-latitudes were much colder than average. In an attempt to better understand the physical characteristics for cold Eurasian winters, major sources of variability in surface air temperature (SAT) are investigated based on cyclostationary EOF analysis. The two leading modes of SAT variability represent the effect of Arctic amplification (AA) and the Arctic oscillation (AO), respectively. These two modes are distinct in terms of the physical characteristics, including surface energy fluxes and tropospheric circulations, and result in significantly different winter SAT patterns over the Eurasian continent. The AA-related SAT anomalies are dipolar with warm Arctic, centered at the Barents–Kara Seas, and cold East Asia. In contrast, the negative AO-related SAT anomalies are characterized by widespread cold anomalies in Northern Eurasia. Relative importance of the AA and the negative AO contributions to cold Eurasian winters is sensitive to the region of interest.

  10. 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

  11. Physical Causes of Drop Size Distribution Variability

    NASA Astrophysics Data System (ADS)

    Zawadzki, I.

    Drop size distributions are measured at ground by instruments (disdrometers) that mostly sample one drop at a time or at best, a small number of drops simultaneously. To obtain a representative sample a time window of the observations is required. This introduces a spurious variability due to the differential fall speed of drops coupled with a highly variable field of precipitation in rapid displacement respect to the dis- drometer. A filter has been studied to minimize this spurious variability as well as instrumental uncertainty. The use of filtered data allows to see case to case differences in DSDs that are hidden in the large scatter in the raw data. These differences can be associated to physical processes revealed by a vertically pointing radar such as the de- gree of aggregation, riming, etc. Numerical modeling of particle size evolution using the quasi-stochastic growth equation serves as guide for the understanding of these processes.

  12. Parent and Peer Predictors of Physical Dating Violence Perpetration in Early Adolescence: Tests of Moderation and Gender Differences

    PubMed Central

    Miller, Shari; Gorman-Smith, Deborah; Sullivan, Terri; Orpinas, Pamela; Simon, Thomas R.

    2013-01-01

    This study examined parenting and peer predictors of physical dating violence perpetration during early adolescence and tested moderation among these predictors and gender. Participants were 2,824 ethnically diverse sixth-grade students with a recent boyfriend/girlfriend who was part of a multisite, longitudinal investigation of the development and prevention of violence among middle school students. Those students who reported having a boyfriend/girlfriend reported significantly more drug use and delinquent activity and were more likely to be male. Twenty-nine percent of youth with a boyfriend/girlfriend reported perpetrating physical aggression against their boyfriend/girlfriend. Parenting and peer variables were significant predictors of physical dating violence. However, gender moderated the association between parenting practices and physical dating violence, with parental monitoring inversely linked to dating violence for boys and parent support for nonaggression inversely linked to dating violence for girls. Parent support for aggression also moderated the association between peer deviancy and reported perpetration. Finally, gender moderated the interaction between peer deviancy and parent support for nonaggressive solutions. PMID:20183640

  13. Probing Young Star Physics with Aperiodic Variability

    NASA Astrophysics Data System (ADS)

    Findeisen, Krzysztof

    2014-01-01

    Ongoing time domain surveys such as PTF, CRTS, and Pan-STARRS1, as well as upcoming surveys such as LSST, promise to revolutionize optical astronomy by providing a comprehensive picture of the variability properties of everything from local flare stars to distant quasars. Time domain surveys have already proven a boon for studies of young stars, whose variability is frequently aperiodic and may have time scales of days to decades, depending on the physics underlying the variability. I present an overview of the PTF-NAN (North America Nebula) survey, which allows us, for the first time, to simultaneously resolve day-scale variability and to monitor changes in photometric behavior in young stars over several years, without large data gaps and without any assumptions about periodicity. I describe preliminary results of the survey, including a search for episodic stellar behavior, a study of the most robust methods for identifying the characteristic time scale(s) of an aperiodic signal, and a characterization of the full range of amplitudes and time scales represented in optical variability of young stars.

  14. Circadian Phenotype Composition is a Major Predictor of Diurnal Physical Performance in Teams

    PubMed Central

    Facer-Childs, Elise; Brandstaetter, Roland

    2015-01-01

    Team performance is a complex phenomenon involving numerous influencing factors including physiology, psychology, and management. Biological rhythms and the impact of circadian phenotype have not been studied for their contribution to this array of factors so far despite our knowledge of the circadian regulation of key physiological processes involved in physical and mental performance. This study involved 216 individuals from 12 different teams who were categorized into circadian phenotypes using the novel RBUB chronometric test. The composition of circadian phenotypes within each team was used to model predicted daily team performance profiles based on physical performance tests. Our results show that the composition of circadian phenotypes within teams is variable and unpredictable. Predicted physical peak performance ranged from 1:52 to 8:59 p.m. with performance levels fluctuating by up to 14.88% over the course of the day. The major predictor for peak performance time in the course of a day in a team is the occurrence of late circadian phenotypes. We conclude that circadian phenotype is a performance indicator in teams that allows new insight and a better understanding of team performance variation in the course of a day as often observed in different groupings of individuals. PMID:26483754

  15. Optimism and depression as predictors of physical and mental health functioning: the Normative Aging Study.

    PubMed

    Achat, H; Kawachi, I; Spiro, A; DeMolles, D A; Sparrow, D

    2000-01-01

    Dispositional optimism has been linked in previous studies to better health outcomes. We sought to examine the independent associations of dispositional optimism and depressive symptoms with physical and mental functioning in a cohort of healthy middle-aged and older men. The study was conducted among 659 subjects in the Veterans Administration (VA) Normative Aging Study. Dispositional optimism and depressive symptomatology were measured in 1991 and 1990, respectively, by the Life Orientation Test and the Center for Epidemiologic Studies--Depression Scale (CES-D). The dependent variables, functioning and well-being, were measured in 1992 by the Medical Outcomes Study Short-Form Health Survey (SF-36). In multivariate regression models, optimism was associated with higher levels of general health perceptions, vitality, and mental health, and lower levels of bodily pain, but not to physical functioning, social functioning, or role limitations due to physical or emotional problems. Depressive symptomatology was associated with reduced levels of functioning across all SF-36 domains. The findings for optimism and depression were statistically significant after mutual adjustment in multivariate regression models. Optimism and depression are independent predictors of functional status among aging men. PMID:10962705

  16. Predictors of long-term change of a physical activity promotion programme in primary care

    PubMed Central

    2014-01-01

    Background Further research is needed to improve the evidence regarding determinants of physical activity (PA) as a crucial step to plan higher effective intervention strategies. The goal of the present study is to identify socio-demographic and clinical characteristics of primary care (PHC) insufficiently active patients that are associated with longitudinal changes in the level of physical activity. Methods Longitudinal analysis of baseline socio-demographic and clinical predictors of physical activity change in insufficiently active PHC patients who participated in a PA-promoting multi-centre randomized clinical trial conducted from October 2003 through March 2006. The primary outcome measure was the self-reported physical activity assessed with the 7-day Physical Activity Recall (PAR), at baseline, 6, 12 and 24 months. Baseline covariates included sex, age, social class, anthropometric measures and other cardiovascular risk factors or associated diseases (Diabetes, HTA, tobacco use, etc.), and stage of readiness to change PA. Generalized linear mixed models were used to estimate longitudinal association of studied variables on PA change over the three follow-up measurements. Results A total of 3691 patients (85% of the 4317 recruited in the trial) with at least one follow-up measurement were included in the longitudinal analysis. At baseline, analysed patients (mean age: 50.6 years; 64.6% women) devoted 34.7 minutes and 2.36 metabolic equivalent hours per week (MET.h/week) to moderate and vigorous physical activity. Older age, male gender, higher social class, lower BMI, diagnosis of diabetes or hypertension, and measurement season were significant predictors of PA longitudinal change. The effect of baseline readiness to change on PA dose was modified by time, showing a positive gradient in favour of those with more readiness to change that increases significantly at 12 and 24 months (p-value interaction < .0001). Conclusions Identified baseline

  17. Short-Term Variability and Predictors of Urinary Pentachlorophenol Levels in Ohio Preschool Children

    PubMed Central

    Morgan, Marsha; Jones, Paul; Sobus, Jon

    2015-01-01

    Pentachlorophenol (PCP) is a persistent and ubiquitous environmental contaminant. No published data exist on the temporal variability or important predictors of urinary PCP concentrations in young children. In this further analysis of study data, we have examined the associations between selected sociodemographic or lifestyle factors and urinary PCP concentrations in 115 preschool children over a 48-h period and assessed the 48-hour variability of urinary PCP levels in a subset of 15 children. Monitoring was performed at 115 homes and 16 daycares in Ohio (USA) in 2001. Questionnaires/diaries and spot urine samples were collected from each child. The median urinary PCP level was 0.8 ng/mL (range < 0.2–23.8 ng/mL). The intraclass correlation coefficient for urinary PCP was 0.42, which indicates fairly low reliability for a single sample over a 48-h period. In a multiple regression model, age of home and ln(creatinine levels) were significant predictors and sampling season, time spent outside, and pet ownership were marginally significant predictors of ln(urinary PCP levels), collectively explaining 29% of the variability of PCP in urine. To adequately assess short-term exposures of children to PCP, several spot urine measurements are likely needed as well as information regarding residence age, seasonality, time spent outdoors, and pet ownership. PMID:25594782

  18. Physical activity - an important preanalytical variable

    PubMed Central

    Sanchis-Gomar, Fabian; Lippi, Giuseppe

    2014-01-01

    The concentration of several biochemical and hematological biomarkers is strongly influenced by a number of preanalytical variables. Several lines of evidence attest that short, middle, and long-term exercise, as well as the relative intensity of physical effort (from mild to strenuous), may influence a broad array of laboratory variables. The amount of extracellular release and clearance from blood of most of these biomarkers is markedly influenced by the biological characteristics of the molecule(s), level of training, type, intensity and duration of exercise, and time of recovery after training. It is hence noteworthy that test results that fall outside the conventional reference ranges in athletes not only may reflect the presence of a given disease, but may frequently mirror an adaptation to regular training or changes that have occurred during and/or following strenuous exercise, and which should be clearly acknowledged to prevent misinterpretation of laboratory data. The aim of this narrative review is to provide an update about the most significant changes of some biochemical and hematological biomarkers in response to physical exercise, for appropriate interpretation of these changes in the context of physically active subjects. PMID:24627716

  19. Heart Rate Variability as a Predictor of Death in Burn Patients.

    PubMed

    Loguidice, Michael J; Schutt, Robert C; Horton, Jureta W; Minei, Joseph P; Keeley, Ellen C

    2016-01-01

    Heart rate variability (HRV), a noninvasive technique used to quantify fluctuations in the interval between normal heart beats (NN), is a predictor of mortality in some patient groups. The aim of this study was to assess HRV in burn trauma patients as a predictor of mortality. The authors prospectively performed 24-hour Holter monitoring on burn patients and collected demographic information, burn injury details, and in-hospital clinical events. Analysis of HRV in the time and frequency domains was performed. A total of 40 burn patients with a mean age of 44 ± 15 years were enrolled. Mean %TBSA burn was 27 ± 22% for the overall population and was significantly higher in those who died compared with those who survived (55 ± 23% vs 19 ± 13%; P < .0001). There was a statistically significant inverse linear correlation between SD of NN intervals and %TBSA (r = -.337, R = 0.113, 95% CI = -0.587 to -0.028, two-tailed P = .034), as well as with ultra low frequency power and %TBSA burn (r = -0.351, R = 0.123, 95% CI = -0.152 to -0.009; P = .027). The receiver-operator characteristic showed the area under the curve for %TBSA as a predictor of death was 0.82 (P < .001), for SDANN was 0.94 (P < .0001), and for ultra low frequency power was 0.96 (P < .0001). Deranged HRV in the early postburn period is a strong predictor of death. PMID:26061155

  20. Physical activity during pregnancy: predictors of change, perceived support and barriers among women at increased risk of gestational diabetes.

    PubMed

    Leppänen, Marja; Aittasalo, Minna; Raitanen, Jani; Kinnunen, Tarja I; Kujala, Urho M; Luoto, Riitta

    2014-11-01

    The aim of this study was to examine the predictors of change in intensity-specific leisure-time physical activity (LTPA) during pregnancy, and the perceived support and barriers of LTPA in Finnish pregnant women at increased risk of gestational diabetes. The study population consisted of 399 pregnant women who participated in a randomized controlled trial aiming to prevent gestational diabetes. Evaluation of LTPA was based on a self-report at baseline, 26-28, and 36-37 weeks' gestation. Data on predictors of change, perceived support and barriers were collected with questionnaires and from the maternity cards. Multinomial logistic regression was used to assess associations between the variables. The average weekly minutes of light-intensity LTPA were 179 at baseline, 161 at 26-28 weeks' gestation, and 179 at 36-37 weeks' gestation. The corresponding minutes of moderate-to-vigorous-intensity LTPA were 187, 133 and 99. At 26-28 weeks' gestation, the strongest predictors for light-intensity LTPA were meeting the PA recommendations prior to pregnancy, having polytechnic education and working part-time, while having a physically active spouse prior to pregnancy was the strongest predictor for moderate-to-vigorous-intensity LTPA. The people and/or factors that encouraged women to LTPA the most were the spouse, a child, other family members and weather, whereas tiredness, nausea, perceived health, work and lack of time restricted their LTPA the most. The strongest predictors for maintaining LTPA during pregnancy were pre-pregnancy LTPA, education, working part-time and a spouse's LTPA. Most common barriers were perceived health, work and lack of time. PMID:24615354

  1. Identifying Predictors of Physics Item Difficulty: A Linear Regression Approach

    ERIC Educational Resources Information Center

    Mesic, Vanes; Muratovic, Hasnija

    2011-01-01

    Large-scale assessments of student achievement in physics are often approached with an intention to discriminate students based on the attained level of their physics competencies. Therefore, for purposes of test design, it is important that items display an acceptable discriminatory behavior. To that end, it is recommended to avoid extraordinary…

  2. Predictors of Obesity and Physical Health Complaints Among 911 Telecommunicators

    PubMed Central

    Lilly, Michelle M.; London, Melissa J.; Mercer, Mary C.

    2015-01-01

    Background This study aims to: (1) examine rates of obesity and physical health complaints among 911 telecommunicators; and (2) document the role of emotion dysregulation, psychological inflexibility, duty-related distress and dissociation, and psychopathology in predicting obesity and physical health complaints in this population. Methods The sample consisted of 911 telecommunicators from across the country (N = 758). Participants completed an online survey assessing their mental and physical health functioning. Results A total of 82.5% of the sample reported a body mass index that fell within the overweight or obese category and an average of 17 physical health complaints within the past month. Peritraumatic reactions (distress and dissociation), emotion dysregulation, and psychological inflexibility had effects on physical health largely through psychopathology (alcohol abuse, post-traumatic stress disorder, and depression). Conclusion Development of adapted prevention and intervention efforts with this population is needed. PMID:27014492

  3. Flood regionalization: A hybrid geographic and predictor-variable region-of-influence regression method

    USGS Publications Warehouse

    Eng, K.; Milly, P.C.D.; Tasker, Gary D.

    2007-01-01

    To facilitate estimation of streamflow characteristics at an ungauged site, hydrologists often define a region of influence containing gauged sites hydrologically similar to the estimation site. This region can be defined either in geographic space or in the space of the variables that are used to predict streamflow (predictor variables). These approaches are complementary, and a combination of the two may be superior to either. Here we propose a hybrid region-of-influence (HRoI) regression method that combines the two approaches. The new method was applied with streamflow records from 1,091 gauges in the southeastern United States to estimate the 50-year peak flow (Q50). The HRoI approach yielded lower root-mean-square estimation errors and produced fewer extreme errors than either the predictor-variable or geographic region-of-influence approaches. It is concluded, for Q50 in the study region, that similarity with respect to the basin characteristics considered (area, slope, and annual precipitation) is important, but incomplete, and that the consideration of geographic proximity of stations provides a useful surrogate for characteristics that are not included in the analysis. ?? 2007 ASCE.

  4. Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children.

    PubMed

    Gonçalves, R; Szmuchrowski, L A; Prado, L S; Couto, B P; Machado, Jcq; Damasceno, V O; Lamounier, J A

    2015-09-01

    The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. PMID:26424930

  5. Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children

    PubMed Central

    Szmuchrowski, LA; Prado, LS; Couto, BP; Machado, JCQ; Damasceno, VO; Lamounier, JA

    2014-01-01

    The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. PMID:26424930

  6. Self-Efficacy as a Predictor of Self-Reported Physical, Cognitive and Social Functioning in Multiple Sclerosis

    PubMed Central

    Schmitt, Margaret M.; Goverover, Yael; DeLuca, John; Chiaravalloti, Nancy

    2014-01-01

    Objective Investigate whether self-efficacy is associated with physical, cognitive and social functioning in individuals with Multiple Sclerosis (MS) when controlling for disease-related characteristics and depressive symptomatology. Participants 81 individuals between the ages of 29 and 67 with a diagnosis of clinically definite MS. Method Hierarchical regression analysis was employed to examine the relationships between self-efficacy and self-reported physical, cognitive, and social functioning. Results Self-efficacy is a significant predictor of self-reported physical, cognitive and social functioning in MS after controlling for variance due to disease related factors and depressive symptomatology. Conclusions Self-efficacy plays a significant role in individual adjustment to MS across multiple areas of functional outcome, beyond that which is accounted for by disease related variables and symptoms of depression. PMID:24320946

  7. Predictors of Substance Use and Family Therapy Outcome among Physically and Sexually Abused Runaway Adolescents

    ERIC Educational Resources Information Center

    Slesnick, Natasha; Bartle-Haring, Suzanne; Gangamma, Rashmi

    2006-01-01

    There is a dearth of research that examines the impact of family systems therapy on problems among sexually and/or physically abused youth. Given this void, differential outcome and predictors of substance use change were evaluated for abused, as compared with nonabused, runaway adolescents who were randomly assigned to family therapy or treatment…

  8. Predictors of Latent Trajectory Classes of Physical Dating Violence Victimization

    ERIC Educational Resources Information Center

    Brooks-Russell, Ashley; Foshee, Vangie A.; Ennett, Susan T.

    2013-01-01

    This study identified classes of developmental trajectories of physical dating violence victimization from grades 8 to 12 and examined theoretically-based risk factors that distinguished among trajectory classes. Data were from a multi-wave longitudinal study spanning 8th through 12th grade (n = 2,566; 51.9 % female). Growth mixture models were…

  9. Patterns, Variability, and Predictors of Urinary Bisphenol A Concentrations during Childhood.

    PubMed

    Stacy, Shaina L; Eliot, Melissa; Calafat, Antonia M; Chen, Aimin; Lanphear, Bruce P; Hauser, Russ; Papandonatos, George D; Sathyanarayana, Sheela; Ye, Xiaoyun; Yolton, Kimberly; Braun, Joseph M

    2016-06-01

    We examined the patterns, variability, and predictors of urinary bisphenol A (BPA) concentrations in 337 children from the Cincinnati, Ohio HOME Study. From 2003 to 2014, we collected two urine samples from women at 16 and 26 weeks of pregnancy and six urine samples from children at 1-5 and 8 years of age. We used linear mixed models to calculate intraclass correlation coefficients (ICCs) as a measure of within-person BPA variability and to identify sociodemographic and environmental predictors. For the 8-year visit, we used multivariable linear regression to explore associations between urinary BPA concentrations and exposure-related factors. We calculated daily intakes using equations estimating creatinine excretion rates and creatinine-standardized BPA concentrations. Urinary BPA concentrations, which decreased over childhood, had a low degree of reproducibility (ICC < 0.2). Estimated daily intakes decreased with age and were below the reference dose of 50 μg/kg body weight/day. BPA concentrations were positively associated with consuming food stored or heated in plastic, consuming canned food and beverages, and handling cash register receipts. Our results suggest that there are multiple sources of BPA exposure in young children. Etiological studies should collect serial urine samples to accurately classify BPA exposure and consider sociodemographic and environmental factors as possible confounders. PMID:27152530

  10. Validation of spatial variability in downscaling results from the VALUE perfect predictor experiment

    NASA Astrophysics Data System (ADS)

    Widmann, Martin; Bedia, Joaquin; Gutiérrez, Jose Manuel; Maraun, Douglas; Huth, Radan; Fischer, Andreas; Keller, Denise; Hertig, Elke; Vrac, Mathieu; Wibig, Joanna; Pagé, Christian; Cardoso, Rita M.; Soares, Pedro MM; Bosshard, Thomas; Casado, Maria Jesus; Ramos, Petra

    2016-04-01

    VALUE is an open European network to validate and compare downscaling methods for climate change research. Within VALUE a systematic validation framework to enable the assessment and comparison of both dynamical and statistical downscaling methods has been developed. In the first validation experiment the downscaling methods are validated in a setup with perfect predictors taken from the ERA-interim reanalysis for the period 1997 - 2008. This allows to investigate the isolated skill of downscaling methods without further error contributions from the large-scale predictors. One aspect of the validation is the representation of spatial variability. As part of the VALUE validation we have compared various properties of the spatial variability of downscaled daily temperature and precipitation with the corresponding properties in observations. We have used two test validation datasets, one European-wide set of 86 stations, and one higher-density network of 50 stations in Germany. Here we present results based on three approaches, namely the analysis of i.) correlation matrices, ii.) pairwise joint threshold exceedances, and iii.) regions of similar variability. We summarise the information contained in correlation matrices by calculating the dependence of the correlations on distance and deriving decorrelation lengths, as well as by determining the independent degrees of freedom. Probabilities for joint threshold exceedances and (where appropriate) non-exceedances are calculated for various user-relevant thresholds related for instance to extreme precipitation or frost and heat days. The dependence of these probabilities on distance is again characterised by calculating typical length scales that separate dependent from independent exceedances. Regionalisation is based on rotated Principal Component Analysis. The results indicate which downscaling methods are preferable if the dependency of variability at different locations is relevant for the user.

  11. Predictors of physical restraint in a psychiatric emergency setting

    PubMed Central

    Hadi, Fatemeh; Khosravi, Termeh; Shariat, Seyed Vahid; Jalali Nadoushan, Amir Hossein

    2015-01-01

    Background: Considering the negative consequences of using physical restraints, we conducted this study to identify patients who are more frequently restrained in a psychiatric emergency ward as an initial step to limit the use of restraint to the minimum possible. Methods: This was a retrospective case control study conducted in Iran Psychiatric Hospital in Tehran, Iran. We reviewed the files of 607 patients who were admitted during a one year period using convenience sampling; of them, 186 were in the restrained group and 421 in the unrestrained group. Results: Surprisingly, no significant difference was found between the restrained and unrestrained groups in demographic characteristics. The patients who were referred because of violence were diagnosed as having methamphetamine induced psychotic disorder or bipolar I disorder in manic 1episode and had a higher odds of being restrained (OR=2.51, OR=1.61, and OR=1.57 respectively). Being restrained was also associated with a longer duration of hospitalization and duration of staying in the emergency ward. Moreover, patients in their first admission were more frequently restrained. Conclusion: Medical and nursing staff should consider special measures for the patients who are at a higher risk for being restrained. More frequent visits and education for both patients and staff may be effective in reducing the number of physical restraints for these groups of patients. PMID:26913259

  12. A Data Mining Approach for Examining Predictors of Physical Activity among Older Urban Adults

    PubMed Central

    Yoon, Sunmoo; Suero-Tejeda, Niurka; Bakken, Suzanne

    2015-01-01

    This study applied innovative data mining techniques to a community survey dataset to develop prediction models for two aspects of physical activity (active transport and screen time) in sample of older, primarily Hispanic, urban adults (N=2, 514). Main predictors for active transport (accuracy=69.29%, precision .67, recall .69) were immigrant status, high level of anxiety, having a place for physical activity, and willingness to make time for physical activity. The main predictors for screen time (accuracy=63.13%, precision .60, recall .63) were willingness to make time for exercise, having a place for exercise, age, and availability of family support to look up health information on the Internet. Data mining methods were useful to identify intervention targets and inform design of customized interventions. PMID:25941800

  13. A Data Mining Approach for Examining Predictors of Physical Activity Among Urban Older Adults.

    PubMed

    Yoon, Sunmoo; Suero-Tejeda, Niurka; Bakken, Suzanne

    2015-07-01

    The current study applied innovative data mining techniques to a community survey dataset to develop prediction models for two aspects of physical activity (i.e., active transport and screen time) in a sample of urban, primarily Hispanic, older adults (N=2,514). Main predictors for active transport (accuracy=69.29%, precision=0.67, recall=0.69) were immigrant status, high level of anxiety, having a place for physical activity, and willingness to make time for physical activity. The main predictors for screen time (accuracy=63.13%, precision=0.60, recall=0.63) were willingness to make time for exercise, having a place for exercise, age, and availability of family support to access health information on the Internet. Data mining methods were useful to identify intervention targets and inform design of customized interventions. PMID:25941800

  14. Variability and Predictors of Urinary Concentrations of Phthalate Metabolites during Early Childhood

    PubMed Central

    2015-01-01

    The variability and predictors of urinary concentrations of phthalate metabolites in preschool-aged children have not been thoroughly examined. Additionally, the impact of temporal changes in the use and restriction of phthalates in children’s products has not been assessed. Our objective was to identify demographic, behavioral, and temporal predictors of urinary phthalate metabolite concentrations in young children. Between 2004 and 2011, we collected up to five urine samples from each of 296 children participating in a prospective birth cohort during annual study visits at ages 1–5 years. We used linear mixed models to calculate intraclass correlation coefficients (ICCs), a measure of within-individual reproducibility, and identify demographic predictors of urinary phthalate metabolites. We used multivariable linear regression to examine cross-sectional relationships between food packaging or personal care product use and phthalate metabolites measured at age 5 years. Across annual measurements, monoethyl phthalate exhibited the least variation (ICC = 0.38), while di-2-ethylhexyl phthalate (ΣDEHP) metabolites exhibited the most variation (ICC = 0.09). Concentrations changed with age, suggesting age-related changes in phthalate exposure and perhaps metabolism. Our findings suggest that fast food consumption may be a source of butylbenzyl phthalate and di-isononyl phthalate (DiNP) exposure, and some personal care products may be sources of diethyl phthalate exposure. Concentrations of ΣDEHP metabolites decreased over the study period; however, concentrations of DiNP metabolites increased. This finding suggests that manufacturer practices and regulations, like the Consumer Product Safety Improvement Act of 2008, may decrease DEHP exposure, but additional work characterizing the nature and toxicity of replacements is critically needed. PMID:24977926

  15. Parent and Peer Predictors of Physical Dating Violence Perpetration in Early Adolescence: Tests of Moderation and Gender Differences

    ERIC Educational Resources Information Center

    Miller, Shari; Gorman-Smith, Deborah; Sullivan, Terri; Orpinas, Pamela; Simon, Thomas R.

    2009-01-01

    This study examined parenting and peer predictors of physical dating violence perpetration during early adolescence and tested moderation among these predictors and gender. Participants were 2,824 ethnically diverse sixth-grade students with a recent boyfriend/girlfriend who was part of a multisite, longitudinal investigation of the development…

  16. Predictors of willingness to pay for physical activity of socially vulnerable groups in community-based programs.

    PubMed

    Herens, Marion C; van Ophem, Johan A C; Wagemakers, Annemarie M A E; Koelen, Maria A

    2015-01-01

    Willingness to pay (WTP) is used to assess individuals' value attribution to health-related quality of life interventions. Little is known about predictors of WTP for sport and physical activity in socially vulnerable groups in community-based physical activity (CBHEPA) programs. This study addresses the questions: What is the WTP for sport and physical activity of participants in CBHEPA programs, expressed in WTPmoney and WTPtime? Which factors predict WTPmoney and WTPtime? From the literature, predictors for WTP for sport and physical activity were identified: (1) personal and socio-economic predictors: income, education, age, and ethnic origin, (2) health-related predictors: perceived health, life satisfaction, sense of coherence, self-efficacy, (3) sport and physical activity-related predictors: duration and frequency of participation, leisure-time sport or physical activity, sport club membership, enjoyment, and membership fee. Data were gathered for WTPmoney and WTPtime (n = 268) in 19 groups in an evaluation study of CBHEPA programs. Ordered probit was used for analyses. WTPmoney was a monthly average of €9.6. WTPtime was on average 17.6 min travel time. Income was found as predictor for both WTPmoney and WTPtime. Other predictors for WTPmoney were: duration and frequency of program participation, enjoyment, and (former) sport club membership. Low income and younger age were found as predictors for WTPtime. Predictors for WTPmoney are related to income and sport and physical activity experiences, for WTPtime to income and age. Short-term program satisfaction is probably more decisive for WTPmoney than long-term perspectives of improving health-related quality of life. PMID:26405646

  17. Should Faculty Rank Be Included as a Predictor Variable in Studies of Gender Equity in University Faculty Salaries?

    ERIC Educational Resources Information Center

    Boudreau, Nancy; And Others

    1997-01-01

    Two studies illustrate how omitting faculty rank as a predictor variable from gender equity studies of faculty salaries can lead to incorrect conclusions about gender discrimination. One uses hypothetical data constructed so there is no gender difference in salary, but omission of academic rank skews the results. The second uses data from a…

  18. Self Efficacy and Some Demographic Variables as Predictors of Occupational Stress among Primary School Teachers in Delta State of Nigeria

    ERIC Educational Resources Information Center

    Akpochafo, G. O.

    2014-01-01

    This study investigated self efficacy and some demographic variables as predictors of occupational stress among primary school teachers in Delta State. Three hypotheses were formulated to guide the study. The study adopted a descriptive survey design that utilized an expost-facto research type. A sample of one hundred and twenty primary school…

  19. Predictors of hazardous drinking, tobacco smoking and physical inactivity in vocational school students

    PubMed Central

    2013-01-01

    Background Tobacco smoking, hazardous drinking and physical inactivity during adolescence are risk factors that are associated with poorer health in adulthood. The identification of subgroups of young people with a high prevalence of one or more of these risk factors allows an optimised allocation of preventive measures. This study aimed at investigating hazardous drinking, tobacco smoking and physical inactivity as well as their associations and demographic predictors in vocational school students. Methods Out of 57 contacted vocational schools in Switzerland, a total of 24 schools participated in a survey assessing gender, age, immigrant background, educational attainment and vocational field as well as the above mentioned health risk factors. Out of the 2659 students present in 177 included vocational school classes, 2647 (99.5%) completed the survey. Binary logistic regression analyses were conducted to investigate the demographic predictors of each health risk factor and a multinomial logistic regression analysis was conducted to investigate predictors of different risk factor combinations. Results Of the surveyed students, 79.4% showed at least one risk factor, 43.6% showed two or more and 9.6% showed all three health risk factors. Hazardous drinking was more prevalent in male, physical inactivity was more prevalent in female vocational school students. The proportion of students with low physical activity and tobacco smoking increased with increasing age. While the combination of hazardous drinking and tobacco smoking was higher in males, the other risk factor combinations were observed particularly among females. Conclusions Multiple risk factors were ascertained in a significant proportion of vocational school students. Specifically, tobacco smoking and hazardous drinking were coexistent. The study underlines the need for preventive measures in specific subpopulations of adolescents and young adults with lower educational level. PMID:23672294

  20. Psychological factors related to physical education classes as predictors of students' intention to partake in leisure-time physical activity.

    PubMed

    Baena-Extremera, Antonio; Granero-Gallegos, Antonio; Ponce-de-León-Elizondo, Ana; Sanz-Arazuri, Eva; Valdemoros-San-Emeterio, María de Los Ángeles; Martínez-Molina, Marina

    2016-04-01

    In view of the rise in sedentary lifestyle amongst young people, knowledge regarding their intention to partake in physical activity can be decisive when it comes to instilling physical activity habits to improve the current and future health of school students. Therefore, the object of this study was to find a predictive model of the intention to partake in leisure- time physical activity based on motivation, satisfaction and competence. The sample consisted of 347 Spanish, male, high school students and 411 female students aged between 13 and 18 years old. We used a questionnaire made up of the Sport Motivation Scale, Sport Satisfaction Instrument, and the competence factor in the Basic Psychological Needs in Exercise Scale and Intention to Partake in Leisure-Time Physical Activity, all of them adapted to school Physical Education. We carried out confirmatory factor analyses and structural equation models. The intention to partake in leisure-time physical activity was predicted by competence and the latter by satisfaction/fun. Intrinsic motivation was revealed to be the best predictor of satisfaction/fun. Intrinsic motivation should be enhanced in order to predict an intention to partake in physical activity in Physical Education students. PMID:27076009

  1. 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

  2. Running With the Pack: Teen Peer-Relationship Qualities as Predictors of Adult Physical Health.

    PubMed

    Allen, Joseph P; Uchino, Bert N; Hafen, Christopher A

    2015-10-01

    This study assessed qualities of adolescent peer relationships as long-term predictors of physical health quality in adulthood. In an intensive multimethod, multireporter study of a community sample of 171 individuals assessed repeatedly from the ages of 13 to 27 years, physical health quality in adulthood was robustly predicted by independent reports of early-adolescent close-friendship quality and by a pattern of acquiescence to social norms in adolescent peer relationships. Predictions remained after accounting for numerous potential confounds, including prior health problems, concurrent body mass index, anxious and depressive symptoms, personality characteristics, adolescent-era financial adversity, and adolescent-era physical attractiveness. These findings have important implications for understanding the unique intensity of peer relationships in adolescence. PMID:26290522

  3. Running With the Pack: Teen Peer-Relationship Qualities as Predictors of Adult Physical Health

    PubMed Central

    Allen, Joseph P.; Uchino, Bert N.; Hafen, Christopher A.

    2015-01-01

    This study assessed qualities of adolescent peer relationships as long-term predictors of physical health quality in adulthood. In an intensive multimethod, multireporter study of a community sample of 171 individuals assessed repeatedly from the ages of 13 to 27 years, physical health quality in adulthood was robustly predicted by independent reports of early-adolescent close-friendship quality and by a pattern of acquiescence to social norms in adolescent peer relationships. Predictions remained after accounting for numerous potential confounds, including prior health problems, concurrent body mass index, anxious and depressive symptoms, personality characteristics, adolescent-era financial adversity, and adolescent-era physical attractiveness. These findings have important implications for understanding the unique intensity of peer relationships in adolescence. PMID:26290522

  4. Predictor variables of happiness and its connection with risk and protective factors for health.

    PubMed

    Garaigordobil, Maite

    2015-01-01

    Great thinkers, philosophers, scientists, and artists from History have often been concerned about one of the most important elements of life: happiness. The study had four goals: (1) To analyze possible differences in feelings of happiness as a function of sex and age; (2) To explore the relations of happiness with risk factors (psychopathological symptoms, behavior problems) and protective factors (self-concept-self-esteem, cooperative behavior, social skills) for health; (3) To identify predictor variables of happiness; and (4) To explore whether self-esteem mediates the relationship between happiness and psychopathological symptoms. The sample comprised 286 adolescents (14-16 years old). The study used a descriptive, correlational, and cross-sectional methodology. Seven assessment instruments were administered. The ANOVAs confirm that there are no sex differences, but happiness decreases as age increases. Pearson coefficients show that adolescents with more feelings of happiness had fewer psychopathological symptoms (somatization, obsession-compulsion, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, psychoticism…), fewer behavioral problems (school-academic, antisocial behavior, shyness-withdrawal, psychopathological, psychosomatic), high social adaptation, high self-concept/self-esteem, many cooperative behaviors, many appropriate social skills, and few negative social skills (inappropriate assertiveness, impulsiveness, jealousy-withdrawal). Multiple regression analysis identified five variables predicting happiness: high self-concept, few symptoms of depression, many cooperative behaviors, high self-esteem, and low psychoticism. Results showed a partial mediational effect of self-esteem in the relation between happiness and psychopathological symptoms. The discussion focuses on the importance of implementing programs to promote feelings of happiness, as well as protective factors for health (self

  5. Predictor Variables and Screening Protocol for Depressive and Anxiety Disorders in Cancer Outpatients

    PubMed Central

    Lima, Manuela Polidoro; Longatto-Filho, Adhemar; Osório, Flávia L.

    2016-01-01

    Background Cancer patients are at increased risk of persistent depressive and anxiety symptoms and disorders compared to the general population. However, these issues are not always identified, which may worsen the prognosis and increase morbidity and mortality. Therefore, the objectives of this study are to identify predictor variables (demographic and clinical) for the development of mood and anxiety disorders in cancer outpatients and to propose a probabilistic screening protocol considering these variables and certain standardized screening instruments. Methods A total of 1,385 adults, of both genders, receiving outpatient cancer care were evaluated using a questionnaire and screening instruments. Thereafter, 400 of these subjects responded to the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID-IV) by telephone to confirm or rule out the presence of a Current Major Depressive Episode (CMDE) or Anxiety Disorder (AD). Results Of the patients surveyed, 64% met the criteria for CMDE and 41% for AD. Female gender was found to be a risk factor for both disorders, and the presence of previous psychiatric history and marital status (divorced and widowed) were risk factors for anxiety disorders. When scoring above the recommended cutoff score, the screening instruments also indicated a risk of the studied disorders. Based on these findings, a screening protocol and nomograms were created for the quantification, combination and probabilistic estimate of risk, with accuracy indicators >0.68. Conclusion The prevalence rates for the disorders under study are extremely high in cancer patients. The use of the proposed protocol and nomogram can facilitate rapid and wide screening, thus refining triage and supporting the establishment of criteria for referral to mental health professionals, so that patients can be properly diagnosed and treated. PMID:26954671

  6. Predictor variables of happiness and its connection with risk and protective factors for health

    PubMed Central

    Garaigordobil, Maite

    2015-01-01

    Great thinkers, philosophers, scientists, and artists from History have often been concerned about one of the most important elements of life: happiness. The study had four goals: (1) To analyze possible differences in feelings of happiness as a function of sex and age; (2) To explore the relations of happiness with risk factors (psychopathological symptoms, behavior problems) and protective factors (self-concept-self-esteem, cooperative behavior, social skills) for health; (3) To identify predictor variables of happiness; and (4) To explore whether self-esteem mediates the relationship between happiness and psychopathological symptoms. The sample comprised 286 adolescents (14–16 years old). The study used a descriptive, correlational, and cross-sectional methodology. Seven assessment instruments were administered. The ANOVAs confirm that there are no sex differences, but happiness decreases as age increases. Pearson coefficients show that adolescents with more feelings of happiness had fewer psychopathological symptoms (somatization, obsession–compulsion, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, psychoticism…), fewer behavioral problems (school-academic, antisocial behavior, shyness-withdrawal, psychopathological, psychosomatic), high social adaptation, high self-concept/self-esteem, many cooperative behaviors, many appropriate social skills, and few negative social skills (inappropriate assertiveness, impulsiveness, jealousy-withdrawal). Multiple regression analysis identified five variables predicting happiness: high self-concept, few symptoms of depression, many cooperative behaviors, high self-esteem, and low psychoticism. Results showed a partial mediational effect of self-esteem in the relation between happiness and psychopathological symptoms. The discussion focuses on the importance of implementing programs to promote feelings of happiness, as well as protective factors for health (self

  7. Urinary phthalate metabolite concentrations among pregnant women in Northern Puerto Rico: Distribution, temporal variability, and predictors

    PubMed Central

    Cantonwine, David E.; Cordero, José F.; Rivera-González, Luis O.; Del Toro, Liza V. Anzalota; Ferguson, Kelly K.; Mukherjee, Bhramar; Calafat, Antonia M.; Crespo, Noe; Jiménez-Vélez, Braulio; Padilla, Ingrid Y.; Alshawabkeh, Akram N.; Meeker, John D.

    2013-01-01

    , temporal variability, and predictors of phthalate biomarkers among pregnant women in Puerto Rico. Preliminary results suggest several potentially important exposure sources to phthalates in this population and future analysis from this ongoing prospective cohort will help to inform targeted approaches to reduce exposure. PMID:24161445

  8. Spatial-Scale Effects on Relative Importance of Physical Habitat Predictors of Stream Health

    NASA Astrophysics Data System (ADS)

    Frimpong, Emmanuel A.; Sutton, Trent M.; Engel, Bernard A.; Simon, Thomas P.

    2005-12-01

    A common theme in recent landscape studies is the comparison of riparian and watershed land use as predictors of stream health. The objective of this study was to compare the performance of reach-scale habitat and remotely assessed watershed-scale habitat as predictors of stream health over varying spatial extents. Stream health was measured with scores on a fish index of biotic integrity (IBI) using data from 95 stream reaches in the Eastern Corn Belt Plain (ECBP) ecoregion of Indiana. Watersheds hierarchically nested within the ecoregion were used to regroup sampling locations to represent varying spatial extents. Reach habitat was represented by metrics of a qualitative habitat evaluation index, whereas watershed variables were represented by riparian forest, geomorphology, and hydrologic indices. The importance of reach- versus watershed-scale variables was measured by multiple regression model adjusted-R2 and best subset comparisons in the general linear statistical framework. Watershed models had adjusted-R2 ranging from 0.25 to 0.93 and reach models had adjusted-R2 ranging from 0.09 to 0.86. Better-fitting models were associated with smaller spatial extents. Watershed models explained about 15% more variation in IBI scores than reach models on average. Variety of surficial geology contributed to decline in model predictive power. Results should be interpreted bearing in mind that reach habitat was qualitatively measured and only fish assemblages were used to measure stream health. Riparian forest and length-slope (LS) factor were the most important watershed-scale variables and mostly positively correlated with IBI scores, whereas substrate and riffle-pool quality were the important reach-scale variables in the ECBP.

  9. Family predictors of continuity and change in social and physical aggression from ages 9 to 18.

    PubMed

    Ehrenreich, Samuel E; Beron, Kurt J; Brinkley, Dawn Y; Underwood, Marion K

    2014-01-01

    This research examined developmental trajectories for social and physical aggression for a sample followed from age 9 to 18, and investigated possible family predictors of following different trajectory groups. Participants were 158 girls and 138 boys, their teachers, and their parents (21% African American, 5.3% Asian, 51.6% Caucasian, and 21% Hispanic). Teachers rated children's social and physical aggression yearly in grades 3-12. Participants' parent (83% mothers) reported on family income, conflict strategies, and maternal authoritarian and permissive parenting styles. The results suggested that both social and physical aggression decline slightly from middle childhood through late adolescence. Using a dual trajectory model, group-based mixture modeling revealed three trajectory groups for both social and physical aggression: low-, medium-, and high-desisting for social aggression, and stably-low, stably-medium, and high-desisting for physical aggression. Membership in higher trajectory groups was predicted by being from a single-parent family, and having a parent high on permissiveness. Being male was related to both elevated physical aggression trajectories and the medium-desisting social aggression trajectory. Negative interparental conflict strategies did not predict social or physical aggression trajectories when permissive parenting was included in the model. Permissive parenting in middle childhood predicted following higher social aggression trajectories across many years, which suggests that parents setting fewer limits on children's behaviors may have lasting consequences for their peer relations. Future research should examine transactional relations between parenting styles and practices and aggression to understand the mechanisms that may contribute to changes in involvement in social and physical aggression across childhood and adolescence. PMID:24888340

  10. Family Predictors of Continuity and Change in Social and Physical Aggression from Ages 9 – 18

    PubMed Central

    Ehrenreich, Samuel E.; Beron, Kurt J.; Brinkley, Dawn Y.; Underwood, Marion K.

    2014-01-01

    This research examined developmental trajectories for social and physical aggression for a sample followed from age 9–18, and investigated possible family predictors of following different trajectory groups. Participants were 158 girls and 138 boys, their teachers, and their parents (21% African American, 5.3% Asian, 51.6% Caucasian, and 21% Hispanic). Teachers rated children’s social and physical aggression yearly in grades 3–12. Participants’ parent (83% mothers) reported on family income, conflict strategies, and maternal authoritarian and permissive parenting styles. The results suggested that both social and physical aggression decline slightly from middle childhood through late adolescence. Using a dual trajectory model, group based mixture modeling revealed three trajectory groups for both social and physical aggression: low-, medium-, and high-desisting for social aggression, and stably-low, stably-medium, and high-desisting for physical aggression. Membership in higher trajectory groups was predicted by being from a single-parent family, and having a parent high on permissiveness. Being male was related to both elevated physical aggression trajectories and the medium-desisting social aggression trajectory. Negative interparental conflict strategies did not predict social or physical aggression trajectories when permissive parenting was included in the model. Permissive parenting in middle childhood predicted following higher social aggression trajectories across many years, which suggests that parents setting fewer limits on children’s behaviors may have lasting consequences for their peer relations. Future research should examine transactional relations between parenting styles and practices and aggression to understand the mechanisms that may contribute to changes in involvement in social and physical aggression across childhood and adolescence. PMID:24888340

  11. Gender Differences in Predictors of Self-Reported Physical Aggression: Exploring Theoretically Relevant Dimensions among Adolescents from Santiago, Chile

    PubMed Central

    Fries, Lauren; Grogan-Kaylor, Andrew; Bares, Cristina; Han, Yoonsun; Delva, Jorge

    2013-01-01

    Research findings remain unclear on whether different factors predict aggression for adolescent men and women. Given that aggression research is rarely conducted with Latin American populations, the current study used multiple imputation and linear regression to assess gender differences in levels and predictors of self-reported physical aggression among a community sample of young (ages 11 through 17) men (n=504) and women (n = 471) from Santiago, Chile. Results revealed that adolescent women reported engaging in higher levels of physical aggression than men. The variables found to be significantly associated with higher levels of reported aggression—younger age, less family involvement, less parental control, less positive relationships with caregivers, having more friends who act out and use substances, having fewer friends committed to learning, presence of dating violence, and more exposure to neighborhood crime—were not moderated by gender, implying that similar factors are related to aggression in adolescent men and women from Chile. Implications for prevention and intervention efforts to address high-risk adolescents and reduce aggression among Chilean youth are discussed. PMID:24392266

  12. Interparental Violence and Maternal Mood Disorders as Predictors of Adolescent Physical Aggression within the Family

    PubMed Central

    Narayan, Angela J.; Chen, Muzi; Martinez, Pedro P.; Gold, Philip W.; Klimes-Dougan, Bonnie

    2015-01-01

    Although a wealth of research has examined the effects of parental mood disorders on offspring maladjustment, studies have not identified whether elevated interparental violence (IPV) may be an exacerbating influence in this pathway. This study examined levels of physical IPV perpetration and victimization in mothers with unipolar depression or Bipolar Disorder (BD) and the processes by which maternal physical IPV moderated adolescents’ physical aggression in families with maternal mood disorders. Mothers with lifetime mood disorders were predicted to have elevated IPV compared to well mothers, and maternal IPV was expected to moderate the association between lifetime mood disorders and adolescent aggression. Participants included 61 intact families with maternal depression (n = 24), BD (n = 13), or well mothers (n = 24) and two siblings (ages 10 to 18 years). Using the Conflict Tactics Scale, mothers reported on IPV perpetration and victimization, and adolescents reported on physical aggression. Mothers with BD reported significantly higher IPV perpetration, but not victimization, than depressed or well mothers. An interaction between maternal BD and IPV perpetration was a significant predictor of adolescent aggression. Main effects of maternal IPV victimization and interaction effects of maternal depression and either type of IPV on adolescent aggression were not significant. Adolescents of mothers who have BD and perpetrate IPV may be particularly vulnerable to being aggressive. Prevention and policy efforts to deter transmission of aggression in high-risk families should target families with maternal BD and intervene at the level of conflict resolution within the family. PMID:25418790

  13. Variability in baseline travel behaviour as a predictor of changes in commuting by active travel, car and public transport: a natural experimental study

    PubMed Central

    Heinen, Eva; Ogilvie, David

    2016-01-01

    Purpose To strengthen our understanding of the impact of baseline variability in mode choice on the likelihood of travel behaviour change. Methods Quasi-experimental analyses in a cohort study of 450 commuters exposed to a new guided busway with a path for walking and cycling in Cambridge, UK. Exposure to the intervention was defined using the shortest network distance from each participant’s home to the busway. Variability in commuter travel behaviour at baseline was defined using the Herfindahl–Hirschman Index, the number of different modes of transport used over a week, and the proportion of trips made by the main (combination of) mode(s). The outcomes were changes in the share of commute trips (i) involving any active travel, (ii) involving any public transport, and (iii) made entirely by car. Variability and change data were derived from a self-reported seven-day record collected before (2009) and after (2012) the intervention. Separate multinomial regression models were estimated to assess the influence of baseline variability on behaviour change, both independently and as an interaction effect with exposure to the intervention. Results All three measures of variability predicted changes in mode share in most models. The effect size for the intervention was slightly strengthened after including variability. Commuters with higher baseline variability were more likely to increase their active mode share (e.g. for HHI: relative risk ratio [RRR] for interaction 3.34, 95% CI 1.41, 7.89) and decrease their car mode share in response to the intervention (e.g. for HHI: RRR 7.50, 95% CI 2.52, 22.34). Conclusions People reporting a higher level of variability in mode choice were more likely to change their travel behaviour following an intervention. Future research should consider such variability as a potential predictor and effect modifier of travel and physical activity behaviour change, and its significance for the design and targeting of interventions. PMID

  14. Buprenorphine versus methadone for opioid dependence: predictor variables for treatment outcome.

    PubMed

    Gerra, G; Borella, F; Zaimovic, A; Moi, G; Bussandri, M; Bubici, C; Bertacca, S

    2004-07-15

    The present study compared in a clinical non-experimental setting the efficacy of buprenorphine (BUP) and methadone (METH) in the treatment of opioid dependence: all the subjects included in the study showed severe long-lasting heroin addiction. Participants (154) were applicants to a 12 weeks treatment program, who were assigned to either METH (78) (mean doses 81.5 +/- 36.4 mg) or BUP (76) (mean doses 9.2 +/- 3.4 mg) treatment. Aim of the study was to evaluate patient/treatment variables possibly influencing retention rate, abstinence from illicit drugs and mood changes. METH patients showed a higher retention rate at week 4 (78.2 versus 65.8) (P < 0.05), but BUP and METH were equally effective in sustaining retention in treatment and compliance with medication at week 12 (61.5 versus 59.2). Retention rate was influenced by dose, psychosocial functioning and not by psychiatric comorbidity in METH patients. In contrast, BUP maintained patients who completed the observational period showed a significantly higher rate of depression than those who dropped out (P < 0.01) and the intention to treat sample (P < 0.05). No relationship between retention and dose, or retention and psychosocial functioning was evidenced for BUP patients. The risk of positive urine testing was similar between METH and BUP, as expression of illicit drug use in general. At week 12, the patients treated with METH showed more risk of illicit opioid use than those treated with BUP (32.1% versus 25.6%) (P < 0.05). Negative urines were associated with higher doses in both METH and BUP patients. As evidenced for retention, substance abuse history and psychosocial functioning appear unable to influence urinalyses results in BUP patients. Buprenorphine maintained patients who showed negative urines presented a significantly higher rate of depression than those with positive urines (P < 0.05). Alternatively, psychiatric comorbidity was found unrelated to urinalyses results in METH patients. Our data

  15. Prevalence and predictors of unsupervised walking and physical activity in a community population of women with fibromyalgia.

    PubMed

    López-Roig, Sofía; Pastor, María-Ángeles; Peñacoba, Cecilia; Lledó, Ana; Sanz, Yolanda; Velasco, Lilian

    2016-08-01

    Physical exercise is recognized as a component of the evidence-based guidelines for treatment of fibromyalgia. Walking is a low-moderate intensity exercise easily adaptable to a fibromyalgia patient's situation. The present study aims to estimate the prevalence of unsupervised walking for exercise in women with fibromyalgia, to describe their level of physical activity and to identify their predictors among socio-demographic, symptom perception and medical advice to walk. A cross-sectional survey with 920 women (all members of fibromyalgia associations) completed the International Physical Activity Questionnaire-Short Form and self-reported scales to assess symptom perception, walking, medical advice to walk and physical comorbidity. The prevalence of reported walking regularly as physical exercise was 30.8 % and it was predicted by medical advice (odds ratio, OR 1.876), age (OR 1.021) and fatigue intensity (OR 0.912). The prevalence of physical activity was 16 % for high-intensity activity, 40 % for moderate activity and 44 % for low activity. Predictors of low versus moderate and high physical activity were pain intensity (OR 1.171) and fatigue impact perception (OR 1.076). Evidence shows a low percentage of women with fibromyalgia walking regularly for physical exercise. Most reported low or moderate physical activity. The results indicate the importance of doctors' advice in promoting walking. Symptom perception and socio-demographic characteristics were weak predictors. Further work is required to examine other determinants of these low levels. PMID:27262713

  16. Predictors and Sequelae of Trajectories of Physical Aggression in School-Age Boys and Girls

    PubMed Central

    Campbell, Susan B.; Spieker, Susan; Vandergrift, Nathan; Belsky, Jay; Burchinal, Margaret

    2013-01-01

    Teacher-rated trajectories of physical aggression in boys and girls from 1st through 6th grade were examined using data from the NICHD Study of Early Child Care and Youth Development. In separate analyses, four trajectories were identified in boys and three in girls. Higher levels of aggression in both boys and girls were related to greater sociodemographic risk and higher maternal harshness in the preschool years; lower levels of observed maternal sensitivity during early childhood also predicted higher trajectories of aggression among girls. Trajectory groups also differed on a range of social and academic adjustment outcomes in 6th grade, with the most aggressive children and even moderately aggressive children evidencing some difficulties in adjustment. Patterns and levels of aggression in boys and girls are discussed as are their predictors and consequences. PMID:20102652

  17. Health-related variables and predictors of Health-promoting Lifestyle in cardiovascular disease patients

    PubMed Central

    Mohsenipouya, Hossein; Majlessi, Fereshteh; Shojaeizadeh, Davood; Foroushani, Abbas Rahimi; Ghafari, Rahman; Habibi, Vali; Makrani, Azam Seyfi

    2016-01-01

    Introduction The principal cause for death in the world is cardiovascular disease. Poor lifestyle is a contributing element in this regard. The objective of this study was to estimate the effects of health-related variables and lifestyle variables on the results of exercise stress tests in patients with cardiovascular disease in Iran. Methods The study population in this case-control study was 220 patients who were candidates for exercise stress tests in Mazandaran Province (Iran) in 2015. The patients were divided randomly into two groups based on the results of their exercise stress tests, i.e., positive (110 patients) and negative (110 patients). The data collection tool was a standard questionnaire entitled “Health promotion lifestyle profile-II.” The data were analyzed using mean, standard deviation, the chi-squared test, and logistic regression by SPSS version 22 software. Results The risk of a positive exercise stress test increases with age. The age group above 65 was 1.049 times more at risk of a positive exercise stress test than the age group of less than 45. The people with dyslipidemia had 1.635 times greater risk of positive exercise stress tests than the group without dyslipidemia. In addition, patients with hypertension had 1.579 times greater risk of positive exercise stress tests than the group without hypertension. The lack of individual health responsibility (Odds ratio (OR): 1.622), stress management (OR: 1.592), and physical activity (OR: 1.245) contributed more to positive exercise tests than the other risk factors. Conclusion Educational interventions can improve the responsibility for health, physical activity, and stress management among people with the risk of cardiovascular disease. PMID:27280004

  18. Determination of exacerbation predictors in patients with COPD in physical therapy - a longitudinal study

    PubMed Central

    Marino, Diego M.; Marrara, Kamilla T.; Arcuri, Juliano F.; Candolo, Cecília; Jamami, Maurício; Lorenzo, Valéria A. Pires Di

    2014-01-01

    Background Chronic obstructive pulmonary disease (COPD) typically presents the characteristic clinical condition of exacerbation, with more intense symptoms associated with greater functional loss and consequently lower chances of patient survival. Objectives This study sought to determine the predictors of exacerbation, alone or in combination, in patients with chronic obstructive pulmonary disease (COPD) who received physical therapeutic treatment over 6 months. Method This was an observational, longitudinal and prospective study in which 63 COPD patients residing within the municipality of São Carlos, SP, Brazil were evaluated. These patients had COPD stages II and III and were entered into a physical therapy program, consisting of 3 periods of assessment over 6 months. We evaluated the occurrence of acute exacerbation as well as the patients' body mass index (BMI), fat-free mass (FFM), fat-free mass index, forced expiratory volume in 1 second (FEV1), dyspnea, distance walked (DW) in the 6-minute walk test (6MWT) and handgrip strength. Results When applying Cox settings with each covariate separately, the results revealed 5% significance only for the DW in the 6MWT, which demonstrated an interaction between BMI and FFM. Comparison of the 3 periods of assessment across the covariates measured showed a significant difference only for the DW between evaluations in the 3rd and 6th months. Conclusion Upon analyzing the predictors of risk over 6 months of follow-up in patients with COPD, we found that the DW in the 6MWT was associated with the risk of exacerbation, although this risk also depended on the covariates BMI and FFM. PMID:24845022

  19. Electrocardiographic Repolarization‐Related Variables as Predictors of Coronary Heart Disease Death in the Women's Health Initiative Study

    PubMed Central

    Rautaharju, Pentti M.; Zhang, Zhu‐Ming; Vitolins, Mara; Perez, Marco; Allison, Matthew A.; Greenland, Philip; Soliman, Elsayed Z.

    2014-01-01

    Background We evaluated 25 repolarization‐related ECG variables for the risk of coronary heart disease (CHD) death in 52 994 postmenopausal women from the Women's Health Initiative study. Methods and Results Hazard ratios from Cox regression were computed for subgroups of women with and without cardiovascular disease (CVD). During the average follow‐up of 16.9 years, 941 CHD deaths occurred. Based on electrophysiological considerations, 2 sets of ECG variables with low correlations were considered as candidates for independent predictors of CHD death: Set 1, Ѳ(Tp|Tref), the spatial angle between T peak (Tp) and normal T reference (Tref) vectors; Ѳ(Tinit|Tterm), the angle between the initial and terminal T vectors; STJ depression in V6 and rate‐adjusted QTp interval (QTpa); and Set 2, TaVR and TV1 amplitudes, heart rate, and QRS duration. Strong independent predictors with over 2‐fold increased risk for CHD death in women with and without CVD were Ѳ(Tp|Tref) >42° from Set 1 and TaVR amplitude >−100 μV from Set 2. The risk for these CHD death predictors remained significant after multivariable adjustment for demographic/clinical factors. Other significant predictors for CHD death in fully adjusted risk models were Ѳ(Tinit|Tterm) >30°, TV1 >175 μV, and QRS duration >100 ms. Conclusions Ѳ(Tp|Tref) angle and TaVR amplitude are associated with CHD mortality in postmenopausal women. The use of these measures to identify high‐risk women for further diagnostic evaluation or more intense preventive intervention warrants further study. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000611. PMID:25074699

  20. 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...

  1. Predictors of Adult Quality of Life for Foster Care Alumni with Physical and/or Psychiatric Disabilities

    ERIC Educational Resources Information Center

    Anctil, Tina M.; McCubbin, Laurie D.; O'Brien, Kirk; Pecora, Peter; Anderson-Harumi, Cheryl A.

    2007-01-01

    Introduction: This study used quality of life and resilience as theoretical frameworks for evaluating predictors of outcomes for adults who received foster care services alumni of foster care and were diagnosed with a physical or psychiatric disability while in foster care. Method: First, outcomes for foster care alumni with and without physical…

  2. Performance-based measures of physical function as mortality predictors: Incremental value beyond self-reports

    PubMed Central

    Goldman, Noreen; Glei, Dana A.; Rosero-Bixby, Luis; Chiou, Shu-Ti; Weinstein, Maxine

    2015-01-01

    BACKGROUND Although previous studies have indicated that performance assessments strongly predict future survival, few have evaluated the incremental value in the presence of controls for self-reported activity and mobility limitations. OBJECTIVE We assess and compare the added value of four tests – walking speed, chair stands, grip strength, and peak expiratory flow (PEF) – for predicting all-cause mortality. METHODS Using population-based samples of older adults in Costa Rica (n = 2290, aged 60+) and Taiwan (n = 1219, aged 53+), we estimate proportional hazards models of mortality for an approximate five-year period. Receiver Operator Characteristic (ROC) curves are used to assess the prognostic value of each performance assessment. RESULTS Self-reported measures of physical limitations contribute substantial gains in mortality prediction, whereas performance-based assessments yield modest incremental gains. PEF provides the greatest added value, followed by grip strength. Our results suggest that including more than two performance assessments may provide little improvement in mortality prediction. CONCLUSIONS PEF and grip strength are often simpler to administer in home interview settings, impose less of a burden on some respondents, and, in the presence of self-reported limitations, appear to be better predictors of mortality than do walking speed or chair stands. COMMENTS Being unable to perform the test is often a strong predictor of mortality, but these indicators are not well-defined. Exclusion rates vary by the specific task and are likely to depend on the underlying demographic, health, social and cultural characteristics of the sample. PMID:25866473

  3. Short- and long-term theory-based predictors of physical activity in women who participated in a weight-management program.

    PubMed

    Wasserkampf, A; Silva, M N; Santos, I C; Carraça, E V; Meis, J J M; Kremers, S P J; Teixeira, P J

    2014-12-01

    This study analyzed psychosocial predictors of the Theory of Planned Behavior (TPB) and Self-Determination Theory (SDT) and evaluated their associations with short- and long-term moderate plus vigorous physical activity (MVPA) and lifestyle physical activity (PA) outcomes in women who underwent a weight-management program. 221 participants (age 37.6 ± 7.02 years) completed a 12-month SDT-based lifestyle intervention and were followed-up for 24 months. Multiple linear regression analyses tested associations between psychosocial variables and self-reported short- and long-term PA outcomes. Regression analyses showed that control constructs of both theories were significant determinants of short- and long-term MVPA, whereas affective and self-determination variables were strong predictors of short- and long-term lifestyle PA. Regarding short-term prediction models, TPB constructs were stronger in predicting MVPA, whereas SDT was more effective in predicting lifestyle PA. For long-term models, both forms of PA were better predicted by SDT in comparison to TPB. These results highlight the importance of comparing health behavior theories to identify the mechanisms involved in the behavior change process. Control and competence constructs are crucial during early adoption of structured PA behaviors, whereas affective and intrinsic sources of motivation are more involved in incidental types of PA, particularly in relation to behavioral maintenance. PMID:25274719

  4. Leisure time physical activity, screen time, social background, and environmental variables in adolescents.

    PubMed

    Mota, Jorge; Gomes, Helena; Almeida, Mariana; Ribeiro, José Carlos; Santos, Maria Paula

    2007-08-01

    This study analyzes the relationships between leisure time physical activity (LTPA), sedentary behaviors, socioeconomic status, and perceived environmental variables. The sample comprised 815 girls and 746 boys. In girls, non-LTPA participants reported significantly more screen time. Girls with safety concerns were more likely to be in the non-LTPA group (OR = 0.60) and those who agreed with the importance of aesthetics were more likely to be in the active-LTPA group (OR = 1.59). In girls, an increase of 1 hr of TV watching was a significant predictor of non-LTPA (OR = 0.38). LTPA for girls, but not for boys, seems to be influenced by certain modifiable factors of the built environment, as well as by time watching TV. PMID:18019587

  5. Predictors of gender achievement in physical science at the secondary level

    NASA Astrophysics Data System (ADS)

    Kozlenko, Brittany Hunter

    This study used the 2009 National Assessment of Educational Progress (NAEP) science restricted data-set for twelfth graders. The NAEP data used in this research study is derived from a sample group of 11,100 twelfth grade students that represented a national population of over 3,000,000 twelfth grade students enrolled in science in the United States in 2009. The researcher chose the NAEP data set because it provided a national sample using uniform questions. This study investigated how the factors of socioeconomic status (SES), parental education level, mode of instruction, and affective disposition affect twelfth grade students' physical science achievement levels in school for the sample population and subgroups for gender. The factors mode of instruction and affective disposition were built through factor analysis based on available questions from the student surveys. All four factors were found to be significant predictors of physical science achievement for the sample population. NAEP exams are administered to a national sample that represents the population of American students enrolled in public and private schools. This was a non-experimental study that adds to the literature on factors that impact physical science for both genders. A gender gap is essentially nonexistent at the fourth grade level but appears at the eighth grade level in science based on information from NAEP (NCES, 1997). The results of the study can be used to make recommendation for policy change to diminish this gender gap in the future. Educators need to be using research to make instructional decisions; research-based instruction helps all students.

  6. Predictors of Performance in Introductory Finance: Variables within and beyond the Student's Control

    ERIC Educational Resources Information Center

    Englander, Fred; Wang, Zhaobo; Betz, Kenneth

    2015-01-01

    This study examined variables that are within and beyond the control of students in explaining variations in performance in an introductory finance course. Regression models were utilized to consider whether the variables within the student's control have a greater impact on course performance relative to the variables beyond the student's…

  7. Physics Of Variable-Polarity Plasma Arc Welding

    NASA Technical Reports Server (NTRS)

    Walsh, Daniel W.; Nunes, Arthur C., Jr.

    1990-01-01

    Report describes experimental study of some of the physical and chemical effects that occur during variable-polarity plasma arc (VPPA) keyhole welding of 2219 aluminum alloy. Comprised three major programs: (1) determination of effects of chemical additions (i.e., impurities) on structure and shape of bead and keyhole; (2) determination of flow in regions surrounding keyhole; (3) development of analog used easily to study flow in keyhole region.

  8. 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. PMID:24954610

  9. Racial differences in parental perceptions of the neighborhood as predictors of children's physical activity and sedentary behavior

    PubMed Central

    Budd, Elizabeth L.; Aaron Hipp, J.; Geary, Nora; Dodson, Elizabeth A.

    2015-01-01

    Objective Most U.S. children engage in insufficient physical activity (PA) and spend too much time in sedentary behaviors (SBs), leading to increased risk of obesity and chronic disease. Evidence remains inconsistent on relationships between parental perceptions of the neighborhood and children's PA and SB. This study examines parental neighborhood perceptions, stratified by race, as predictors of children's PA and SB. Methods Relationships were tested with regressions stratified by parental race. The sample included 196 parents, residing in St. Louis, Missouri with a child at home. Participants responded to a mailed survey in 2012. Parental neighborhood perceptions were examined by mean composite scores and individual items. Results For parents of all races, perceived barriers negatively predicted the number of days in a week children engaged in ≥ 60 min of PA. Examining parental neighborhood perceptions by individual item, the perception that drivers exceed neighborhood speed limits was a positive predictor of their children's SB only among white parents. Only among minority-race parents was perceived neighborhood crime rate a positive predictor of their children's SB. Conclusions While predictors of children's PA did not differ widely, several distinct predictors of children's SB by parental race lend support toward further examination of this topic. PMID:26844096

  10. Spatial variability of snow physical properties across northwestern Greenland

    NASA Astrophysics Data System (ADS)

    Courville, Z.; Polashenski, C.; Dibb, J. E.; Domine, F.

    2013-12-01

    In the late spring and early summer of 2013, researchers on the SAGE (Sunlight Absorption on the Greenland ice sheet Experiment) Traverse, embarked on a 4000 km ground traverse across northwestern Greenland in an attempt to quantify spatial variability of snow chemistry, snow physical properties, and snow reflectance. The field team targeted sites first visited by Carl Benson during his series of traverses from 1952 to 1955 as part of his pioneering work to characterize the Greenland Ice Sheet. This route now represents a rapidly changing and variable area of Greenland, as the route passes through several of the ice sheet facies first delimited by Benson. Along the traverse, the SAGE field team made ground-based albedo measurements using a hand-held spectroradiometer and collected snow physical property samples to determine snow specific surface area (SSA) from shallow, 2m pits. In addition, snow density and stratigraphy were measured. Snow layers in the near-surface and at the previous season's melt layer were targeted for sampling. Here we present preliminary snow physical property results from the upper portion of the snow pits and relate these to surface albedo data collected over the route. Further measurements of snow properties in the 2012 melt layer will be analyzed to assess the potential role of snow chemical (see Dibb et al. for a discussion of chemical analysis) and physical property driven albedo feedbacks could have played in contributing to that event. Route of 2013 SAGE Traverse in northwestern Greenland.

  11. Physical functioning in older blacks: an exploratory study identifying psychosocial and clinical predictors.

    PubMed Central

    Baker, Tamara A.; Whitfield, Keith E.

    2006-01-01

    OBJECTIVES: The primary objective of this investigation was to examine the relationship between physical functioning and various clinical (pain intensity, pain locations, medications, comorbidities) and psychosocial (depression, locus of control) variables in a sample of older blacks. METHODS: Data were collected from community-dwelling black adults (N=247), with a mean age of 69.4 +/- 9.4 years. Participants were recruited from several senior high-rise facilities located in an urban community in Baltimore, MD. A multivariate regression model was tested to determine the relationship between selected clinical, psychosocial and demographic characteristics, and physical functioning; and to assess the amount of unique variance in functional status accounted for by specific psychosocial, clinical and demographic indicators (independently and collectively). RESULTS: It was established that reporting more depressive symptoms (beta=0.18, p<0.05), multiple pain locations (beta=0.25, p<0.01) and pain intensity (beta=0.30, p<0.01) was a significant indicator of physical impairment and accounted for 36% of its variation. CONCLUSION: Identifying indicators of physical impairment is critical in providing baseline information on the functional well-being in older blacks. This emphasizes the need for further studies to rigorously examine the relationship between physical functioning, and clinical and psychosocial indicators within defined race and ethnic groups in order to develop data that provide meaningful comparisons between different race and ethnic groups. PMID:16895281

  12. Self-Concept and Response Variability as Predictors of Leadership Effectiveness in Cooperative Extension.

    ERIC Educational Resources Information Center

    Dvorak, Charles F.

    The research aimed at determining the extent to which two variables, self-concept and response variability, are related to one of the principal components of Fiedler's Contingency Model of leadership, the Esteem for the Least Preferred Coworker (LPC) instrument. Sixty extension workers in the Expanded Food and Nutrition Education Program in New…

  13. Ongoing EEG Phase as a Trial-by-Trial Predictor of Perceptual and Attentional Variability

    PubMed Central

    VanRullen, R.; Busch, N. A.; Drewes, J.; Dubois, Julien

    2011-01-01

    Even in well-controlled laboratory environments, apparently identical repetitions of an experimental trial can give rise to highly variable perceptual outcomes and behavioral responses. This variability is generally discarded as a reflection of intrinsic noise in neuronal systems. However, part of this variability may be accounted for by trial-by-trial fluctuations of the phase of ongoing oscillations at the moment of stimulus presentation. For example, the phase of an electro-encephalogram (EEG) oscillation reflecting the rapid waxing and waning of sustained attention can predict the perception of a subsequent visual stimulus at threshold. Similar ongoing periodicities account for a portion of the trial-by-trial variability of visual reaction times. We review the available experimental evidence linking ongoing EEG phase to perceptual and attentional variability, and the corresponding methodology. We propose future tests of this relation, and discuss the theoretical implications for understanding the neuronal dynamics of sensory perception. PMID:21716580

  14. Physical controls of soil moisture variability at multiple scales

    NASA Astrophysics Data System (ADS)

    Jana, R. B.; Mohanty, B.

    2013-12-01

    Understanding what factors drive soil hydrological processes at different scales and their variability is very critical to further our ability to model the various components of the hydrologic cycle more accurately. Soil moisture, and, by association, soil hydraulic parameters have been known to be a function of location, and the support scale at which they are measured. Recent increase in remote sensing platforms necessitates increased calibration/validation efforts of their soil moisture products with ground-based measurements. Such cal/val operations require some form of up- or down-scaling process. Understanding the factors that drive soil hydrological processes at different scales, and their variability, is very critical to minimize errors due to this step in the cal/val procedure. Existing literature provides a description of the different sources of soil moisture variability across a range of resolutions from point to continental scales, classified under four categories: soil texture and structure, topography, vegetation, and meteorological forcings. While it is accepted that a dynamic relationship exists between these physical controls and the soil hydraulic properties across spatial scales, the nature of the relationship is not very well understood. In order to formulate better scaling algorithms, it is first necessary to determine the form and amount of influence exerted by the controlling factors on the variability of the soil moisture or hydraulic parameters at each scale of interest. One method to understand the effect of the physical controls is to analyze the covariance or coherence of the physical controls with the soil hydraulic properties across multiple scales and different hydro-climates. Such a study, using wavelet analysis, is presented here. A variety of datasets from multiple platforms across the globe were employed in this study. The AMSR-E soil moisture product was used as the remotely sensed, coarse resolution dataset. Fine resolution

  15. Constructing and identifying predictors of frailty among homeless adults—a latent variable structural equations model approach.

    PubMed

    Salem, Benissa E; Nyamathi, Adeline; Brecht, Mary-Lynn; Phillips, Linda R; Mentes, Janet C; Sarkisian, Catherine; Stein, Judith A

    2014-01-01

    Homeless urbanites are a heterogeneous population with unique health and social service needs. The study examined situational, behavioral, health-related and resource indicators in terms of their direct impact on frailty, hypothesized as a latent variable. Using structural equation modeling (SEM), a model was tested with 150 homeless men and women, ages 40–73, from three homeless day center drop-in sites on Skid Row and one residential drug treatment (RDT) facility that works with homeless parolees and probationers. In bivariate analyses with the latent construct frailty, months homeless (p < 0.01), female gender (p < 0.05), education (p < 0.05), comorbid conditions (p < 0.001), nutrition (p < 0.001), resilience (p < 0.001), health care utilization (p < 0.01), and falls (p < 0.001) were significantly associated with frailty. In the final path model, significant predictors of frailty included educational attainment (p < 0.01), comorbid conditions (p < 0.001), nutrition (p < 0.001), resilience (p < 0.001), and falls (p < 0.01). These findings will serve as a foundation for future nurse-led, community-based initiatives that focus on key predictors of frailty among the homeless and the development of interventions. PMID:24505611

  16. Time Outdoors and Physical Activity as Predictors of Incident Myopia in Childhood: A Prospective Cohort Study

    PubMed Central

    Guggenheim, Jeremy A.; Northstone, Kate; McMahon, George; Ness, Andy R.; Deere, Kevin; Mattocks, Calum; Pourcain, Beate St; Williams, Cathy

    2012-01-01

    Purpose. Time spent in “sports/outdoor activity” has shown a negative association with incident myopia during childhood. We investigated the association of incident myopia with time spent outdoors and physical activity separately. Methods. Participants in the Avon Longitudinal Study of Parents and Children (ALSPAC) were assessed by noncycloplegic autorefraction at ages 7, 10, 11, 12, and 15 years, and classified as myopic (≤−1 diopters) or as emmetropic/hyperopic (≥−0.25 diopters) at each visit (N = 4,837–7,747). Physical activity at age 11 years was measured objectively using an accelerometer, worn for 1 week. Time spent outdoors was assessed via a parental questionnaire administered when children were aged 8–9 years. Variables associated with incident myopia were examined using Cox regression. Results. In analyses using all available data, both time spent outdoors and physical activity were associated with incident myopia, with time outdoors having the larger effect. The results were similar for analyses restricted to children classified as either nonmyopic or emmetropic/hyperopic at age 11 years. Thus, for children nonmyopic at age 11, the hazard ratio (95% confidence interval, CI) for incident myopia was 0.66 (0.47–0.93) for a high versus low amount of time spent outdoors, and 0.87 (0.76–0.99) per unit standard deviation above average increase in moderate/vigorous physical activity. Conclusion. Time spent outdoors was predictive of incident myopia independently of physical activity level. The greater association observed for time outdoors suggests that the previously reported link between “sports/outdoor activity” and incident myopia is due mainly to its capture of information relating to time outdoors rather than physical activity. PMID:22491403

  17. Predictors and Variability of Repeat Measurements of Urinary Phenols and Parabens in a Cohort of Shanghai Women and Men

    PubMed Central

    Buckley, Jessie P.; Yang, Gong; Liao, Linda M.; Satagopan, Jaya; Calafat, Antonia M.; Matthews, Charles E.; Cai, Qiuyin; Ji, Bu-Tian; Cai, Hui; Wolff, Mary S.; Rothman, Nathaniel; Zheng, Wei; Xiang, Yong-Bing; Shu, Xiao-Ou; Gao, Yu-Tang; Chow, Wong-Ho

    2014-01-01

    , under certain circumstances, among women. Citation: Engel LS, Buckley JP, Yang G, Liao LM, Satagopan J, Calafat AM, Matthews CE, Cai Q, Ji BT, Cai H, Engel SM, Wolff MS, Rothman N, Zheng W, Xiang YB, Shu XO, Gao YT, Chow WH. 2014. Predictors and variability of repeat measurements of urinary phenols and parabens in a cohort of Shanghai women and men. Environ Health Perspect 122:733–740; http://dx.doi.org/10.1289/ehp.1306830 PMID:24659570

  18. Assessing the spatial variability of coefficients of landslide predictors in different regions of Romania using logistic regression

    NASA Astrophysics Data System (ADS)

    Mărgărint, M. C.; Grozavu, A.; Patriche, C. V.

    2013-12-01

    In landslide susceptibility assessment, an important issue is the correct identification of significant contributing factors, which leads to the improvement of predictions regarding this type of geomorphologic processes. In the scientific literature, different weightings are assigned to these factors, but contain large variations. This study aims to identify the spatial variability and range of variation for the coefficients of landslide predictors in different geographical conditions. Four sectors of 15 km × 15 km (225 km2) were selected for analysis from representative regions in Romania in terms of spatial extent of landslides, situated both on the hilly areas (the Transylvanian Plateau and Moldavian Plateau) and lower mountain region (Subcarpathians). The following factors were taken into consideration: elevation, slope angle, slope height, terrain curvature (mean, plan and profile), distance from drainage network, slope aspect, land use, and lithology. For each sector, landslide inventory, digital elevation model and thematic layers of the mentioned predictors were achieved and integrated in a georeferenced environment. The logistic regression was applied separately for the four study sectors as the statistical method for assessing terrain landsliding susceptibility. Maps of landslide susceptibility were produced, the values of which were classified by using the natural breaks method (Jenks). The accuracy of the logistic regression outcomes was evaluated using the ROC (receiver operating characteristic) curve and AUC (area under the curve) parameter, which show values between 0.852 and 0.922 for training samples, and between 0.851 and 0.940 for validation samples. The values of coefficients are generally confined within the limits specified by the scientific literature. In each sector, landslide susceptibility is essentially related to some specific predictors, such as the slope angle, land use, slope height, and lithology. The study points out that the

  19. Variability of behavioural responses to transcranial magnetic stimulation: Origins and predictors.

    PubMed

    Nicolo, Pierre; Ptak, Radek; Guggisberg, Adrian G

    2015-07-01

    Transcranial magnetic stimulation (TMS) may modulate the excitability of local cortical stimulation sites and distant functionally interconnected regions for minutes, hours or even days. The effects of TMS suggest that it not only acts on activity of the stimulated area, but also on its connections with remote areas. Due to these properties one of the main rationales for the application of TMS in stroke patients is to improve imbalance in interhemispheric inhibition. However, given that TMS may have excitatory or inhibitory effects the impact of stimulation is not easy to predict. In this review, we discuss the different factors that determine the magnitude and quality of physiological and behavioural responses to TMS. Whether TMS is mainly excitatory or inhibitory not only depends on the parameters of stimulation such as pulse frequency and duration, but also on baseline activity of neural tissue before stimulation, or even on cognitive factors such as attention. A major challenge for the application of TMS as therapy method is to identify predictors of positive effects in individual patients. Neuroimaging studies measuring hemodynamic or electrophysiological responses show that changes in interhemispheric competition or adaptations of functional networks in patients with focal brain lesions may predict the individual response to brain stimulation. Such techniques have the potential to select the most appropriate among different intervention methods for an individual patient. PMID:25619851

  20. Comparing Perceived and Objectively Measured Access to Recreational Facilities as Predictors of Physical Activity in Adolescent Girls

    PubMed Central

    Evenson, Kelly R.; Cohen, Deborah A.; Cox, Christine E.

    2007-01-01

    A number of studies in recent years have identified both self-report and objectively measured accessibility of recreational facilities as important predictors of physical activity in youth. Yet, few studies have: (1) examined the relationship between the number and proximity of objectively measured neighborhood physical activity facilities and respondents’ perceptions and (2) compared objective and self-report measures as predictors of physical activity. This study uses data on 1,367 6th-grade girls who participated in the Trial of Activity for Adolescent Girls (TAAG) to explore these issues. Girls reported whether nine different types of recreational facilities were easily accessible. These facilities included basketball courts, golf courses, martial arts studios, playing fields, tracks, skating rinks, swimming pools, tennis courts, and dance/gymnastic clubs. Next, geographic information systems (GIS) were used to identify all the parks, schools, and commercial sites for physical activity located within a mile of each girl’s home. These sites were then visited to inventory the types of facilities available. Girls wore accelerometers to measure their weekly minutes of non-school metabolic equivalent weighted moderate-to-vigorous physical activity (MW-MVPA). The number of facilities within a half-mile of girls’ homes strongly predicted the perception of easy access to seven out of nine facility types. Both individual facility perceptions and the total number of facilities perceived were associated with increased physical activity. For each additional facility perceived, girls clocked 3% more metabolic equivalent weighted moderate-to-vigorous physical activity (p < 0.001). Although girls tended to record 3% more of this kind of physical activity (p < 0.05) per basketball court within a mile of their homes, objective facility measures were otherwise unrelated to physical activity. The results from this study suggest that raising the profile of existing

  1. The Relationship between Grades Earned in Introductory Nursing Courses and Several Predictor Variables: An Exploratory Study.

    ERIC Educational Resources Information Center

    Spahr, Anthony E.

    A study was conducted at Morton College (Illinois) to gain a better understanding of the factors which contribute to academic success in introductory nursing courses, and to investigate the relationship between the following variables: student grades in Fundamentals of Nursing I and II, Anatomy and Physiology I, and Rhetoric I; and their scores on…

  2. A Correlational Study of Preadmission Predictor Variables and Dental School Performance.

    ERIC Educational Resources Information Center

    Kress, Gerard C.; Dogon, I. Leon

    1981-01-01

    Undergraduate performance and standardized test scores were correlated with dental school performance for 131 members of nine Harvard School of Dental Medicine classes to determine the predictive validity of the earlier variables. The only significant positive correlation was of the Dental Admission Test and dental National Board Examination, part…

  3. Obstetric and Parental Psychiatric Variables as Potential Predictors of Autism Severity

    ERIC Educational Resources Information Center

    Wallace, Anna E.; Anderson, George M.; Dubrow, Robert

    2008-01-01

    Associations between obstetric and parental psychiatric variables and subjects' Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS) domain scores were examined using linear mixed effects models. Data for the 228 families studied were provided by the Autism Genetic Resource Exchange. Hypertension (P =…

  4. Noncognitive Variables as Predictors of Achievement in Freshmen English. AIR 1996 Annual Forum Paper.

    ERIC Educational Resources Information Center

    House, J. Daniel; Prion, Susan K.

    This study investigated the correlation between noncognitive variables and academic success in a freshman composition course. A sample of 257 freshmen taking an introductory English course completed a survey assessing their attitudes and achievement expectancies. The questionnaire measured self-ratings of overall academic ability, drive to…

  5. Admission Criteria and Other Variables as Predictors of Business Student Graduation

    ERIC Educational Resources Information Center

    Truell, Allen D.; Woosley, Sherry

    2008-01-01

    Previous research has largely overlooked discipline specific admission criteria at the undergraduate level and its relationship to student success. Thus, the purpose of this study was to determine if college of business admission criteria and other variables predicted undergraduate college of business student graduation. The specific variables…

  6. Cognitive Ability and Personality Variables as Predictors of School Grades and Test Scores in Adolescents

    ERIC Educational Resources Information Center

    Hofer, Manfred; Kuhnle, Claudia; Kilian, Britta; Fries, Stefan

    2012-01-01

    The predictive power of cognitive ability and self-control strength for self-reported grades and an achievement test were studied. It was expected that the variables use of time structure, academic procrastination, and motivational interference during learning further aid in predicting students' achievement because they are operative in situations…

  7. Child Predictors of Learning to Control Variables via Instruction or Self-Discovery

    ERIC Educational Resources Information Center

    Wagensveld, Barbara; Segers, Eliane; Kleemans, Tijs; Verhoeven, Ludo

    2015-01-01

    We examined the role child factors on the acquisition and transfer of learning the control of variables strategy (CVS) via instruction or self-discovery. Seventy-six fourth graders and 43 sixth graders were randomly assigned to a group receiving direct CVS instruction or a discovery learning group. Prior to the intervention, cognitive, scientific,…

  8. Preveterinary Performance, Admissions Criteria and Personality Variables as Predictors of Success in Veterinary School

    ERIC Educational Resources Information Center

    Render, Gary F.; Jackson, Horace D.

    1975-01-01

    A Purdue University study of veterinary school students' first-year grade point averages in relationship to several variables concluded that in addition to traditional criteria, performance in specific preveterinary courses (in this case, 2-semester organic chemistry) and personality measures contribute to predicting success in veterinary school…

  9. The Use of Demographic and Background Variables as Predictors of Success in Pharmacy School

    ERIC Educational Resources Information Center

    Jacoby, Keith E.; And Others

    1978-01-01

    As part of a larger longitudinal study to analyze the career development process in pharmacy at the University of California, demographic, attitudinal, and prior academic achievement data were collected from first-year students during 1971-1974. The additive value of the PCAT when directly contrasted with existing variables was assessed. (LBH)

  10. Heart rate variability and cognitive function: effects of physical effort.

    PubMed

    Luft, Caroline Di Bernardi; Takase, Emílio; Darby, David

    2009-10-01

    This study investigated alterations in heart rate variability (HRV) and cognitive performance before and after physical effort, for 30 high-level track and field athletes (23 males and 7 females). Interbeat intervals were assessed at the baseline and during each task of a CogState cognitive battery (simple reaction time, choice reaction time, working memory, short-term memory and sustained attention). Time and frequency domain measures of HRV were compared between conditions and between tasks. The results indicated differences in HRV between executive and non-executive tasks. There was a significant increase in sympathetic-modulation-related indices after physical effort. The differences between executive and non-executive tasks were the same in post-test. Correlations were found between HRV and cognitive performance, which differed by speed and accuracy. We conclude that HRV is related to cognitive demand and that the correlation between HRV and cognitive performance seems to be stronger after physical exercise. The results raise questions about the psychophysiological meaning of different HRV signals and this has implications for future research about the relationship between HRV and cognition. PMID:19632295

  11. Development and application of downscaled hydroclimatic predictor variables for use in climate vulnerability and assessment studies

    USGS Publications Warehouse

    Thorne, James; Boynton, Ryan; Flint, Lorraine; Flint, Alan; N'goc Le, Thuy

    2012-01-01

    This paper outlines the production of 270-meter grid-scale maps for 14 climate and derivative hydrologic variables for a region that encompasses the State of California and all the streams that flow into it. The paper describes the Basin Characterization Model (BCM), a map-based, mechanistic model used to process the hydrological variables. Three historic and three future time periods of 30 years (1911–1940, 1941–1970, 1971–2000, 2010–2039, 2040–2069, and 2070–2099) were developed that summarize 180 years of monthly historic and future climate values. These comprise a standardized set of fine-scale climate data that were shared with 14 research groups, including the U.S. National Park Service and several University of California groups as part of this project. We present three analyses done with the outputs from the Basin Characterization Model: trends in hydrologic variables over baseline, the most recent 30-year period; a calibration and validation effort that uses measured discharge values from 139 streamgages and compares those to Basin Characterization Model-derived projections of discharge for the same basins; and an assessment of the trends of specific hydrological variables that links historical trend to projected future change under four future climate projections. Overall, increases in potential evapotranspiration dominate other influences in future hydrologic cycles. Increased potential evapotranspiration drives decreasing runoff even under forecasts with increased precipitation, and drives increased climatic water deficit, which may lead to conversion of dominant vegetation types across large parts of the study region as well as have implications for rain-fed agriculture. The potential evapotranspiration is driven by air temperatures, and the Basin Characterization Model permits it to be integrated with a water balance model that can be derived for landscapes and summarized by watershed. These results show the utility of using a process

  12. Synergies between optical and physical variables in intercepting parabolic targets

    PubMed Central

    Gómez, José; López-Moliner, Joan

    2013-01-01

    Interception requires precise estimation of time-to-contact (TTC) information. A long-standing view posits that all relevant information for extracting TTC is available in the angular variables, which result from the projection of distal objects onto the retina. The different timing models rooted in this tradition have consequently relied on combining visual angle and its rate of expansion in different ways with tau being the most well-known solution for TTC. The generalization of these models to timing parabolic trajectories is not straightforward. For example, these different combinations rely on isotropic expansion and usually assume first-order information only, neglecting acceleration. As a consequence no optical formulations have been put forward so far to specify TTC of parabolic targets with enough accuracy. It is only recently that context-dependent physical variables have been shown to play an important role in TTC estimation. Known physical size and gravity can adequately explain observed data of linear and free-falling trajectories, respectively. Yet, a full timing model for specifying parabolic TTC has remained elusive. We here derive two formulations that specify TTC for parabolic ball trajectories. The first specification extends previous models in which known size is combined with thresholding visual angle or its rate of expansion to the case of fly balls. To efficiently use this model, observers need to recover the 3D radial velocity component of the trajectory which conveys the isotropic expansion. The second one uses knowledge of size and gravity combined with ball visual angle and elevation angle. Taking into account the noise due to sensory measurements, we simulate the expected performance of these models in terms of accuracy and precision. While the model that combines expansion information and size knowledge is more efficient during the late trajectory, the second one is shown to be efficient along all the flight. PMID:23720614

  13. Climate variables as predictors for seasonal forecast of dengue occurrence in Chennai, Tamil Nadu

    NASA Astrophysics Data System (ADS)

    Subash Kumar, D. D.; Andimuthu, R.

    2013-12-01

    Background Dengue is a recently emerging vector borne diseases in Chennai. As per the WHO report in 2011 dengue is one of eight climate sensitive disease of this century. Objective Therefore an attempt has been made to explore the influence of climate parameters on dengue occurrence and use for forecasting. Methodology Time series analysis has been applied to predict the number of dengue cases in Chennai, a metropolitan city which is the capital of Tamil Nadu, India. Cross correlation of the climate variables with dengue cases revealed that the most influential parameters were monthly relative humidity, minimum temperature at 4 months lag and rainfall at one month lag (Table 1). However due to intercorrelation of relative humidity and rainfall was high and therefore for predictive purpose the rainfall at one month lag was used for the model development. Autoregressive Integrated Moving Average (ARIMA) models have been applied to forecast the occurrence of dengue. Results and Discussion The best fit model was ARIMA (1,0,1). It was seen that the monthly minimum temperature at four months lag (β= 3.612, p = 0.02) and rainfall at one month lag (β= 0.032, p = 0.017) were associated with dengue occurrence and they had a very significant effect. Mean Relative Humidity had a directly significant positive correlation at 99% confidence level, but the lagged effect was not prominent. The model predicted dengue cases showed significantly high correlation of 0.814(Figure 1) with the observed cases. The RMSE of the model was 18.564 and MAE was 12.114. The model is limited by the scarcity of the dataset. Inclusion of socioeconomic conditions and population offset are further needed to be incorporated for effective results. Conclusion Thus it could be claimed that the change in climatic parameters is definitely influential in increasing the number of dengue occurrence in Chennai. The climate variables therefore can be used for seasonal forecasting of dengue with rise in minimum

  14. Relative importance of dynamic and static environmental variables as predictors of amphibian diversity patterns

    NASA Astrophysics Data System (ADS)

    Gómez-Rodríguez, Carola; Díaz-Paniagua, Carmen; Bustamante, Javier; Serrano, Laura; Portheault, Alexandre

    2010-11-01

    In this study, we evaluated whether static approaches, such as including only habitat characteristics that do not change over time, are adequate for the assessment of diversity-habitat relationships. We assessed the contribution of habitat characteristics that change over time to the spatial pattern of diversity (variation in species richness and in assemblage composition) in comparison to those characteristics that do not change. We have also provided an integral analysis to evaluate the role of the hydroperiod in structuring amphibian assemblages at any diversity level, including variation in species richness, variation in assemblage composition (i.e., nested pattern or species turnover) and variation in beta diversity. We monitored 19 amphibian assemblages from 2003 to 2006 in a highly fluctuating ecosystem, the temporary ponds in Doñana National Park. Both sets of habitat variables (temporally fixed and temporally variable) were necessary to develop a realistic understanding of amphibian diversity patterns, both when considering data collected in particular years or over several years. We found that environmental attributes that are irrelevant for pond species richness (alpha diversity) might be responsible for the variation in assemblage composition among ponds (beta diversity) and, hence, contribute to species diversity in the entire study area (gamma diversity). Therefore, we illustrate the need for an integral analysis of diversity in order not to disregard any relevant habitat factor. Alternatively, the relevance of the hydroperiod was not constant across time and was negligible in the wet year, while, in the dry year, we observed a strong nested pattern along the hydroperiod gradient and small differences in species predominance among assemblages. Therefore, our results show two conservation priorities in the study area: the preservation of ponds along the wide hydroperiod gradient; and a particular concern for the preservation of ponds with a long

  15. Modifiable variables in physical therapy education programs associated with first-time and three-year National Physical Therapy Examination pass rates in the United States

    PubMed Central

    Cook, Chad; Engelhard, Chalee; Landry, Michel D.; McCallum, Christine

    2015-01-01

    Purpose: This study aimed to examine the modifiable programmatic characteristics reflected in the Commission on Accreditation in Physical Therapy Education (CAPTE) Annual Accreditation Report for all accredited programs that reported pass rates on the National Physical Therapist Examination, and to build a predictive model for first-time and three-year ultimate pass rates. Methods: This observational study analyzed programmatic information from the 185 CAPTE-accredited physical therapy programs in the United States and Puerto Rico out of a total of 193 programs that provided the first-time and three-year ultimate pass rates in 2011. Fourteen predictive variables representing student selection and composition, clinical education length and design, and general program length and design were analyzed against first-time pass rates and ultimate pass rates on the NPTE. Univariate and multivariate multinomial regression analysis for first-time pass rates and logistic regression analysis for three-year ultimate pass rates were performed. Results: The variables associated with the first-time pass rate in the multivariate analysis were the mean undergraduate grade point average (GPA) and the average age of the cohort. Multivariate analysis showed that mean undergraduate GPA was associated with the three-year ultimate pass rate. Conclusions: Mean undergraduate GPA was found to be the only modifiable predictor for both first-time and three-year pass rates among CAPTE-accredited physical therapy programs. PMID:26395081

  16. Physical Activity Behavior Predictors, Reasons and Barriers among Male Adolescents in Riyadh, Saudi Arabia: Evidence for Obesogenic Environment

    PubMed Central

    Alsubaie, Ali S. R.; Omer, Eltigani O.M.

    2015-01-01

    Objective This study aimed to assess physical activity, socio-demographic predictors and to determine reasons for practicing and/or not practicing physical activities. Methods Cross-sectional study was conducted among male high school students in Riyadh, Saudi Arabia. A self-administered questionnaire was used to collect the data using stratified cluster sampling technique (N= 453 students). Results Although 36.4% of the student reported that they practiced enough exercise during their usual week days, only 15.5% of the students were found to be practicing physical activity at a recommended level (≥5 days/week). On the other hand, 20.1% of the students were found to be inactive and not practicing physical activity at any day. Among the factors that associated with adolescents physical activity, logistic regression showed that students age was associated negatively with physical activity behaviour (OR= 0.6, P <0.001). Also, logistic regression showed that students physical activity behaviour was independently associated with students perceived body weight (OR= 27, P <0.001). The main reasons for practicing physical activity were: to enhance muscle and strength (70.9%), to have fun with friend and entertainment (66%), and to improve physical appearance (53.6%), respectively. The main reported barriers inhibiting adolescents from practicing physical activity were: lack of sports facilities in the community (74%), lack of friends and peer support (59.4%) and lack of suitable public sport club in the community (54.6%). Conclusion This study revealed low prevalence of physical activity among adolescents. National strategies to increase levels of physical activity and minimize obesogenic environmental factors are required. PMID:26715919

  17. Social, economic, and resource predictors of variability in household air pollution from cookstove emissions.

    PubMed

    Yadama, Gautam N; Peipert, John; Sahu, Manoranjan; Biswas, Pratim; Dyda, Venkat

    2012-01-01

    We examine if social and economic factors, fuelwood availability, market and media access are associated with owning a modified stove and variation in household emissions from biomass combustion, a significant environmental and health concern in rural India. We analyze cross-sectional household socio-economic data, and PM(2.5) and particulate surface area concentration in household emissions from cookstoves (n=100). This data set combines household social and economic variables with particle emissions indexes associated with the household stove. The data are from the Foundation for Ecological Society, India, from a field study of household emissions. In our analysis, we find that less access to ready and free fuelwood and higher wealth are associated with owning a replacement/modified stove. We also find that additional kitchen ventilation is associated with a 12% reduction in particulate emissions concentration (p<0.05), after we account for the type of stove used. We did not find a significant association between replacement/modified stove on household emissions when controlling for additional ventilation. Higher wealth and education are associated with having additional ventilation. Social caste, market and media access did not have any effect on the presence of replacement or modified stoves or additional ventilation. While the data available to us does not allow an examination of direct health outcomes from emissions variations, adverse environmental and health impacts of toxic household emissions are well established elsewhere in the literature. The value of this study is in its further examination of the role of social and economic factors and available fuelwood from commons in type of stove use, and additional ventilation, and their effect on household emissions. These associations are important since the two direct routes to improving household air quality among the poor are stove type and better ventilation. PMID:23056293

  18. Physical significance of least mean squares criterion in nonstationary lattice predictors

    NASA Astrophysics Data System (ADS)

    Martinelli, G.; Orlandi, G.; Prinaricotti, L.; Ragazzini, S.

    1985-06-01

    An acoustical nonstationary model of the vocal tract is discussed. The effectiveness of the nonstationary lattice predictor in recovering the model is illustrated. The reflection coefficients are linearly decomposed on a function basis and the weights of the linear combinations are the new parameters of the model. Parameters are determined by an algorithm similar to Burg's by minimizing the sum of the variances of the forward and backward residuals. Synthetic signals of good approximation are obtained in two examples.

  19. Logistic Regression for Seismically Induced Landslide Predictions: Using Uniform Hazard and Geophysical Layers as Predictor Variables

    NASA Astrophysics Data System (ADS)

    Nowicki, M. A.; Hearne, M.; Thompson, E.; Wald, D. J.

    2012-12-01

    Seismically induced landslides present a costly and often fatal threats in many mountainous regions. Substantial effort has been invested to understand where seismically induced landslides may occur in the future. Both slope-stability methods and, more recently, statistical approaches to the problem are described throughout the literature. Though some regional efforts have succeeded, no uniformly agreed-upon method is available for predicting the likelihood and spatial extent of seismically induced landslides. For use in the U. S. Geological Survey (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER) system, we would like to routinely make such estimates, in near-real time, around the globe. Here we use the recently produced USGS ShakeMap Atlas of historic earthquakes to develop an empirical landslide probability model. We focus on recent events, yet include any digitally-mapped landslide inventories for which well-constrained ShakeMaps are also available. We combine these uniform estimates of the input shaking (e.g., peak acceleration and velocity) with broadly available susceptibility proxies, such as topographic slope and surface geology. The resulting database is used to build a predictive model of the probability of landslide occurrence with logistic regression. The landslide database includes observations from the Northridge, California (1994); Wenchuan, China (2008); ChiChi, Taiwan (1999); and Chuetsu, Japan (2004) earthquakes; we also provide ShakeMaps for moderate-sized events without landslide for proper model testing and training. The performance of the regression model is assessed with both statistical goodness-of-fit metrics and a qualitative review of whether or not the model is able to capture the spatial extent of landslides for each event. Part of our goal is to determine which variables can be employed based on globally-available data or proxies, and whether or not modeling results from one region are transferrable to

  20. Characterization of the Variability of Epstein-Barr Virus Genes in Nasopharyngeal Biopsies: Potential Predictors for Carcinoma Progression

    PubMed Central

    Banko, Ana V.; Lazarevic, Ivana B.; Folic, Miljan M.; Djukic, Vojko B.; Cirkovic, Andja M.; Karalic, Danijela Z.; Cupic, Maja D.; Jovanovic, Tanja P.

    2016-01-01

    Epstein-Barr virus (EBV) infection is a significant factor in the pathogenesis of nasopharyngeal carcinoma, especially in the undifferentiated carcinoma of nasopharyngeal type (UCNT, World Health Organization type III), which is the dominant histopathological type in high-risk areas. The major EBV oncogene is latent membrane protein 1 (LMP1). LMP1 gene shows variability with different tumorigenic and immunogenic potentials. EBV nuclear antigen 1 (EBNA1) regulates progression of EBV-related tumors; however, the influence of EBNA1 sequence variability on tumor pathogenesis is controversial. The aims of this study were to characterize polymorphisms of EBV genes in non-endemic nasopharyngeal carcinoma biopsies and to investigate potential sequence patterns that correlate with the clinical presentation of nasopharyngeal carcinoma. In total, 116 tumor biopsies of undifferentiated carcinoma of nasopharyngeal type (UCNT), collected from 2008 to 2014, were evaluated in this study. The genes EBNA2, LMP1, and EBNA1 were amplified using nested-PCR. EBNA2 genotyping was performed by visualization of PCR products using gel electrophoresis. Investigation of LMP1 and EBNA1 included sequence, phylogenetic, and statistical analyses. The presence of EBV DNA was significantly distributed between TNM stages. LMP1 variability showed six variants, with the detection of the first China1 and North Carolina variants in European nasopharyngeal carcinoma biopsies. Newly discovered variants Srb1 and Srb2 were UCNT-specific LMP1 polymorphisms. The B95-8 and North Carolina variants are possible predictors for favorable TNM stages. In contrast, deletions in LMP1 are possible risk factors for the most disfavorable TNM stage, independent of EBNA2 or EBNA1 variability. A newly discovered EBNA1 subvariant, P-thr-sv-5, could be a potential diagnostic marker, as it represented a UCNT-specific EBNA1 subvariant. A particular combination of EBNA2, LMP1, and EBNA1 polymorphisms, type 1/Med/P-thr was

  1. Predictors of Burnout Among Nurses in Taiwan.

    PubMed

    Lee, Huan-Fang; Yen, Miaofen; Fetzer, Susan; Chien, Tsair Wei

    2015-08-01

    Nurse burnout is a crucial issue for health care professionals and impacts nurse turnover and nursing shortages. Individual and situational factors are related to nurse burnout with predictors of burnout differing among cultures and health care systems. The predictors of nurse burnout in Asia, particularly Taiwan, are unknown. The purpose of this study was to investigate the predictors of burnout among a national sample of nurses in Taiwan. A secondary data analysis of a nationwide database investigated the predictors of burnout among 1,846 nurses in Taiwan. Hierarchical regression analysis determined the relationship between predictors and burnout. Predictors of Taiwanese nurse burnout were age, physical/psychological symptoms, job satisfaction, work engagement, and work environment. The most significant predictors were physical/psychological symptoms and work engagement. The variables explained 35, 39, and 18 % of the emotional exhaustion, personal accomplishment, and depersonalization variance for 54 % of the total variance of burnout. Individual characteristics and nurse self-awareness, especially work, engagement can impact Taiwanese nurses' burnout. Nurse burnout predictors provide administrators with information to develop strategies including education programs and support services to reduce nurse burnout. PMID:25536942

  2. Habitat and water quality variables as predictors of community composition in an Indonesian coral reef: a multi-taxon study in the Spermonde Archipelago.

    PubMed

    Polónia, Ana Rita Moura; Cleary, Daniel Francis Richard; de Voogd, Nicole Joy; Renema, Willem; Hoeksema, Bert W; Martins, Ana; Gomes, Newton Carlos Marcial

    2015-12-15

    Assemblages of corals, sponges, foraminifera, sediment bacteria and sediment archaea were assessed at two depths in the Spermonde Archipelago. Our goal was to assess to what extent variation in composition could be explained by habitat and water quality variables. The habitat variables consisted of depth, substrate type and scleractinian coral cover while water quality variables were derived from ocean color satellite imagery, including the colored dissolved organic matter index (CDOM), chlorophyll-a (Chlor-a) and remote sensing reflectance at 645n m (Rrs_645). Together, habitat and water quality variables explained from 31% (sediment bacteria) to 80% (forams) of the variation in composition. The variation in composition of corals, sponges, forams and sediment archaea was primarily related to habitat variables, while the variation in composition of sediment bacteria was primarily related to water quality variables. Habitat and water quality variables explained similar amounts of variation in the composition of corals and sediment bacteria. CDOM (sponges, sediment bacteria and sediment archaea), Chlor-a (corals and forams) and Rrs_645 (sponges and forams) proved significant predictors of variation in composition for the studied taxa. In addition to water quality variables, all taxa responded to a range of habitat variables including depth and the percentage cover of various benthic life forms including coral cover variables, rubble and sand. Sand cover was the most important habitat variable for corals, sponges, sediment bacteria and sediment archaea. Coral life forms including the cover of branching and tabular corals were important habitat variables for sponges and forams. These results show marked differences in how various taxa respond to variation in habitat and water quality in the Spermonde Archipelago. Moreover, our results indicate that variables estimated from ocean color satellite imagery proved to be better predictors of variation in marine community

  3. Short- and Long-Term Theory-Based Predictors of Physical Activity in Women Who Participated in a Weight-Management Program

    ERIC Educational Resources Information Center

    Wasserkampf, A.; Silva, M. N.; Santos, I. C.; Carraça, E. V.; Meis, J. J. M.; Kremers, S. P. J.; Teixeira, P. J.

    2014-01-01

    This study analyzed psychosocial predictors of the Theory of Planned Behavior (TPB) and Self-Determination Theory (SDT) and evaluated their associations with short- and long-term moderate plus vigorous physical activity (MVPA) and lifestyle physical activity (PA) outcomes in women who underwent a weight-management program. 221 participants (age…

  4. Predictors of Self-Reported Physical Symptoms in Low-Income, Inner-City African American Women: The Role of Optimism, Depressive Symptoms, and Chronic Illness

    ERIC Educational Resources Information Center

    Jones, Deborah J.; O'Connell, Cara; Gound, Mary; Heller, Laurie; Forehand, Rex

    2004-01-01

    In this study we examined the association of optimism and depressive symptoms with self-reported physical symptoms in 241 low-income, inner-city African American women with or without a chronic illness (HIV). Although optimism was not a unique predictor of self-reported physical symptoms over and above depressive symptoms, optimism interacted with…

  5. The use of effective variables in high energy physics

    NASA Astrophysics Data System (ADS)

    Baumgart, Matthew Todd

    In high energy physics, we often gain by systematically reducing the formal description of a physical system or the data sets that come from particle colliders. Converting the naive, original setup results in a more useful set of couplings, fields, or observables, which we call effective variables. This thesis considers several examples of them: We take a φ4 scalar field theory and renormalize it according to the equations of Wilsonian exact renormalization group. Whatever the initial setup of the theory, this results in an infinite number of operators. We demonstrate a procedure to remove all interaction terms except for the quartic. We find its coupling has the same one-loop beta-function as obtained from standard renormalization group. We also examine the relationship between little Higgs and 5d composite models with identical symmetries. By performing an "extreme" deconstruction, one can reduce any warped composite model to a little Higgs theory on a handful of sites. We find that the finiteness of the Higgs potential in 5d is due to the same collective symmetry breaking as in the little Higgs. We compare a 4d and 5d model with the same symmetry to the data. We see that the 5d model has difficulty meeting several constraints simultaneously. By contrast, the Minimal Moose with custodial symmetry is viable in a large region of its parameter space. Finally, we turn our attentions to the hadron collider environment. In the context of SUSY extended by U(1)', production of an initial Z' gauge boson gives us an additional kinematic constraint. We use this to implement a novel method to measure all of the superpartner masses involved in its decay. For certain final states with two invisible particles, one can construct kinematic observables bounded above by parent particle masses. Additionally, we study other effects of extending the MSSM by a Z '. The production cross-section of sleptons is enhanced over the MSSM, so the discovery potential for sleptons is greatly

  6. Influence of basin-scale physical variables on life history characteristics of cutthroat trout in Yellowstone Lake

    USGS Publications Warehouse

    Gresswell, Robert E.; Liss, W.J.; Larson, Gary L.; Bartlein, P.J.

    1997-01-01

    Individual spawning populations of Yellowstone cutthroat trout Oncorhynchus clarki bouvieri differ in life history characteristics associated with broad spatial and temporal environmental patterns, but relationships between specific life history characteristics of Yellowstone cutthroat trout and physical aspects of the environment are poorly understood. We examined basin-scale physical characteristics of tributary drainages and subbasins of Yellowstone Lake in relation to timing (peak and duration) of lacustrinea??adfluvial Yellowstone cutthroat trout spawning migrations and mean length of cutthroat trout spawners in 27 tributaries to the lake. Stream drainages varied along gradients that can be described by mean aspect, mean elevation, and drainage and stream size. Approximately two-thirds of the variation in the timing of the peak of the annual cutthroat trout spawning migrations and average length of spawners was explained by third-order polynomial regressions with mean aspect and basin area as predictor variables. Because most cutthroat trout ascend tributaries soon after peak runoff, it appears that the influence of basin-scale physical variables on the date of the migration peak is manifested by the pattern of stream discharge. Spawner length does not seem to be a direct function of stream size in the Yellowstone Lake watershed, and aspect of the tributary basin seems to have a greater influence on the body length of cutthroat trout spawners than does stream size. Mechanisms that explain how the interaction of basin-scale physical variables influence spawner length were not investigated directly; however, we found evidence of distinct aggregations of cutthroat trout that are related to physical and limnological characteristics of the lake subbasins, and there is some indication that lake residence may be related to tributary location.

  7. 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.

  8. Understanding Predictors of Low Physical Activity in Adults with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Finlayson, Janet; Jackson, Alison; Cooper, Sally-Ann; Morrison, Jillian; Melville, Craig; Smiley, Elita; Allan, Linda; Mantry, Dipali

    2009-01-01

    Background: Lack of regular physical activity is globally one of the most significant risks to health. The main aims of this study were to describe the types and levels of regular physical activity undertaken by adults with intellectual disabilities, and to investigate the factors predicting low activity. Materials and Methods: Interviews were…

  9. School playgrounds and physical activity policies as predictors of school and home time activity

    PubMed Central

    2011-01-01

    Background Previous work has suggested that the number of permanent play facilities in school playgrounds and school-based policies on physical activity can influence physical activity in children. However, few comparable studies have used objective measures of physical activity or have had little adjustment for multiple confounders. Methods Physical activity was measured by accelerometry over 5 recess periods and 3 full school days in 441 children from 16 primary schools in Dunedin, New Zealand. The number of permanent play facilities (swing, fort, slide, obstacle course, climbing wall etc) in each school playground was counted on three occasions by three researchers following a standardized protocol. Information on school policies pertaining to physical activity and participation in organized sport was collected by questionnaire. Results Measurement of school playgrounds proved to be reliable (ICC 0.89) and consistent over time. Boys were significantly more active than girls (P < 0.001), but little time overall was spent in moderate-vigorous physical activity (MVPA). Boys engaged in MVPA for 32 (SD 17) minutes each day of which 17 (10) took place at school compared with 23 (14) and 11 (7) minutes respectively in girls. Each additional 10-unit increase in play facilities was associated with 3.2% (95% CI 0.0-6.4%) more total activity and 8.3% (0.8-16.3%) more MVPA during recess. By contrast, school policy score was not associated with physical activity in children. Conclusion The number of permanent play facilities in school playgrounds is associated with higher physical activity in children, whereas no relationship was observed for school policies relating to physical activity. Increasing the number of permanent play facilities may offer a cost-effective long-term approach to increasing activity levels in children. PMID:21521530

  10. Predictors of physical activity among rural and small town breast cancer survivors: an application of the theory of planned behaviour.

    PubMed

    Vallance, Jeff K; Lavallee, Celeste; Culos-Reed, Nicole S; Trudeau, Marc G

    2012-01-01

    The primary objective of this study was to investigate the utility of the two-component theory of planned behaviour (TPB) in understanding physical activity intentions and behaviour in rural and small town breast cancer survivors. The secondary objective was to elicit the most common behavioural, normative and control beliefs of rural and small town survivors regarding physical activity. Using a cross-sectional survey design, 524 rural and small town breast cancer survivors completed a mailed survey that assessed physical activity and TPB variables. Physical activity intention explained 12% of the variance in physical activity behaviour (p < 0.01) while the TPB constructs together explained 43% of the variance in physical activity intention (p < 0.01). Unique behavioural, normative and control beliefs were elicited from the sample. The two-component TPB framework appears to be a suitable model to initiate an understanding of physical activity determinants among rural and small town breast cancer survivors. These data can be used in the development and establishment of physical activity behaviour interventions and health promotion materials designed to facilitate physical activity behaviour among rural and small town breast cancer survivors. PMID:22409699

  11. Predictors of depressive symptoms and physical health in caregivers of individuals with schizophrenia.

    PubMed

    Thunyadee, Chanya; Sitthimongkol, Yajai; Sangon, Sopin; Chai-Aroon, Teradech; Hegadoren, Kathleen M

    2015-12-01

    This cross-sectional study examined relationships among factors influencing caregiver burden, depressive symptoms, and physical health in family caregivers of individuals with schizophrenia. Two hundred family caregivers of individuals with schizophrenia completed standardized questionnaires related to depressive symptoms, physical health, perceptions of burden, coping, and social support. The results revealed that 19.5% of family caregivers of individuals with schizophrenia experienced significant depressive symptoms and 65.5% perceived themselves in poor physical health. Burden, self-controlling coping strategies, and physical health status were all independently predictive of depressive symptoms. Two emotion-focused coping strategies (self-controlling and escape-avoidance) were independently predictive of caregiver burden. Only burden predicted physical health status. The findings suggest that health professionals who provide community care for those with schizophrenia need to consider the "unit of care" as the family rather than the individual. The health status of family caregivers should be routinely assessed. Individualized interventions to reduce family burden could include community-based health professionals as well as trained community volunteers, opportunities for social interaction, and improving self-care for all family members. PMID:26081195

  12. Predictors of returning to work.

    PubMed

    Ash, P; Goldstein, S I

    1995-01-01

    An investigation of predictors of returning to work in a sample of physically injured persons who are receiving workers' compensation benefits and vocational rehabilitation is presented. One hundred fourteen injured subjects (86 with back injury; 28, other injury) undergoing vocational rehabilitation and receiving workers' compensation benefits were assessed on demographic, emotional, cognitive, financial incentive, and miscellaneous variables. Predictors for returning to work were identified using stepwise logistic regression. Patients with moderate or severe depression, defined as a score greater than 16 on the Beck Depression Inventory (BDI), were significantly less likely to return to work following vocational rehabilitation efforts than patients with less severe depression (for back-injured patients, odds ratio (OR) = 31, 95% CI [8.8, 108]). BDI scores correctly classified 84 percent of the back-injury and 86% of the other-injury groups with respect to their return to work. The level of workers' compensation benefit was the only variable that added (marginally) to the predictive power of the BDI. In a physically injured population receiving workers' compensation benefits, who are judged to be not clearly permanently disabled, level of depressive symptoms is a strong predictor of returning to work. Caution is warranted in using the BDI as the sole determinant in a forensic situation for making a real-world prediction, as BDI responses are easy to fake. Treatment of concurrent depression is an important component of helping physically injured workers resume gainful employment. PMID:8605404

  13. Pretrauma Problems, Prior Stressor Exposure, and Gender as Predictors of Change in Posttraumatic Stress Symptoms among Physically Injured Children and Adolescents

    ERIC Educational Resources Information Center

    Doron-LaMarca, Susan; Vogt, Dawne S.; King, Daniel W.; King, Lynda A.; Saxe, Glenn N.

    2010-01-01

    Objective: This study addressed predictors of change in posttraumatic stress symptoms (PTSS) among youths who had experienced physical injuries. The influences of pretrauma internalizing and externalizing problems, prior stressor exposure, and gender were investigated. Additionally, gender was examined as a moderator of the associations between…

  14. Child Physical Abuse Prevalence, Characteristics, Predictors, and Beliefs about Parent-Child Violence in South Asian, Middle Eastern, East Asian, and Latina Women in the United States

    ERIC Educational Resources Information Center

    Maker, Azmaira H.; Shah, Priti V.; Agha, Zia

    2005-01-01

    The present study examined the prevalence, characteristics, beliefs, and demographic predictors of parent-child physical violence among South Asian, Middle Eastern, East Asian, and Latina women in the United States. Two hundred fifty-one college-educated women from a middle to high SES (South Asian/Middle Eastern, n = 93; East Asian, n = 72;…

  15. Psychosocial predictors of changes in adolescent girls' physical activity and dietary behaviors over the course of the Go Girls! group-based mentoring program.

    PubMed

    Dowd, A Justine; Chen, Michelle Y; Schmader, Toni; Jung, Mary E; Zumbo, Bruno D; Beauchamp, Mark R

    2016-08-01

    Changes in social cognitions targeted within a group-based mentoring program for adolescent girls were examined as predictors of changes in physical activity (PA) and dietary behavior (in two separate models) over the course of the 7-week program. Data were collected from 310 participants who participated in the program. Multilevel path models were used to assess changes in psychosocial variables predicting changes in behavioral outcomes from pre- to post-program. Analyses revealed that 24.4 and 12.3% of the variance in increases in PA and dietary behavior, respectively, was explained by increases in affective and instrumental attitudes, self-regulatory efficacy (SRE), and intentions. Increases in intentions partially mediated the effects of increases in SRE and affective attitudes on increases in PA behavior. In relation to improvements in dietary behavior, increases in intentions and SRE directly predicted improvements in dietary behavior. These findings suggest potential psychological mechanisms through which a group-based mentoring program may lead to changes in adolescent girls' health-enhancing PA and dietary behaviors. PMID:27325620

  16. A Longitudinal Study of Family Socioeconomic Status (SES) Variables as Predictors of Socio-Emotional Resilience among Mentored Youth

    ERIC Educational Resources Information Center

    Thompson, R. Bruce; Corsello, Maryann; McReynolds, Samuel; Conklin-Powers, Bernice

    2013-01-01

    In this study, we explored socioeconomic status (SES) and family structure as predictors of resiliencies among "at-risk" youth before and after participating in schools-based mentoring programs. Twenty-four youths (13 girls) aged 13-18 ("M" = 16.21, SD = 1.76) participated. Youths completed pre- and post-test…

  17. Acute Stress Disorder as a Predictor of Post-Traumatic Stress Disorder in Physical Assault Victims

    ERIC Educational Resources Information Center

    Elklit, Ask; Brink, Ole

    2004-01-01

    The authors' objective was to examine the ability of acute stress disorder (ASD) and other trauma-related factors in a group of physical assault victims in predicting post-traumatic stress disorder (PTSD) 6 months later. Subjects included 214 victims of violence who completed a questionnaire 1 to 2 weeks after the assault, with 128 participating…

  18. Predisposing, Reinforcing and Enabling Predictors of Middle School Children's After-School Physical Activity Participation

    ERIC Educational Resources Information Center

    King, Kristi M.; Ogletree, Roberta J.; Fetro, Joyce V.; Brown, Stephen L.; Partridge, Julie A.

    2011-01-01

    Children's participation in after-school physical activity can attenuate the overweight and obesity rates among rural, low socioeconomic status (SES) children. Children's individual determination, as well as social and environmental factors, can influence their behaviors. Purpose: The purposes of this study were to determine if a difference…

  19. Everyday Physical Activity as a Predictor of Late-Life Mortality

    ERIC Educational Resources Information Center

    Chipperfield, Judith G.

    2008-01-01

    Purpose: The present study hypothesized that simple, everyday physical activity (EPA) would decline with advancing age; that women would have a more favorable EPA profile than would men; and that EPA would have a survival benefit. Design and Methods: Community-dwelling participants (aged 80-98 years, n = 198) wore mechanical actigraphs in order…

  20. Family Ecological Predictors of Physical Activity Parenting in Low-Income Families

    ERIC Educational Resources Information Center

    Lampard, Amy M.; Jurkowski, Janine M.; Lawson, Hal A.; Davison, Kirsten K.

    2013-01-01

    Physical activity (PA) parenting, or strategies parents use to promote PA in children, has been associated with increased PA in children of all ages, including preschool-aged children. However, little is known about the circumstances under which parents adopt such behaviors. This study examined family ecological factors associated with PA…

  1. Predictors of validity and reliability of a physical activity record in adolescents

    PubMed Central

    2013-01-01

    Background Poor to moderate validity of self-reported physical activity instruments is commonly observed in young people in low- and middle-income countries. However, the reasons for such low validity have not been examined in detail. We tested the validity of a self-administered daily physical activity record in adolescents and assessed if personal characteristics or the convenience level of reporting physical activity modified the validity estimates. Methods The study comprised a total of 302 adolescents from an urban and rural area in Ecuador. Validity was evaluated by comparing the record with accelerometer recordings for seven consecutive days. Test-retest reliability was examined by comparing registrations from two records administered three weeks apart. Time spent on sedentary (SED), low (LPA), moderate (MPA) and vigorous (VPA) intensity physical activity was estimated. Bland Altman plots were used to evaluate measurement agreement. We assessed if age, sex, urban or rural setting, anthropometry and convenience of completing the record explained differences in validity estimates using a linear mixed model. Results Although the record provided higher estimates for SED and VPA and lower estimates for LPA and MPA compared to the accelerometer, it showed an overall fair measurement agreement for validity. There was modest reliability for assessing physical activity in each intensity level. Validity was associated with adolescents’ personal characteristics: sex (SED: P = 0.007; LPA: P = 0.001; VPA: P = 0.009) and setting (LPA: P = 0.000; MPA: P = 0.047). Reliability was associated with the convenience of completing the physical activity record for LPA (low convenience: P = 0.014; high convenience: P = 0.045). Conclusions The physical activity record provided acceptable estimates for reliability and validity on a group level. Sex and setting were associated with validity estimates, whereas convenience to fill out the record was

  2. Physical and sexual abuse in childhood as predictors of early onset cardiovascular events in women

    PubMed Central

    Rich-Edwards, J.W.; Mason, S.; Rexrode, K.; Spiegelman, D.; Hibert, E.; Kawachi, I.; Jun, H.J.; Wright, R.J.

    2012-01-01

    Background Although child abuse is widespread and has been associated with cardiovascular disease (CVD) risk factors, its association with CVD events is not established. Methods and Results We examined associations of child abuse with CVD events among 66,798 women in the Nurses’ Health Study 2. Proportional hazards models estimated hazard ratios (HR) and 95% confidence intervals (CI) for myocardial infarction (n=262), stroke (n=251), and total CVD (n=513). Severe physical abuse was reported by 9% and forced sex by 11% of participants. Adjusting for age, race, childhood body type, parental education and family CVD history, the HR for CVD events was 0.91 (95% CI: 0.70–1.17) for mild physical abuse, 1.02 (0.82–1.26) for moderate physical abuse, and 1.46 (1.11–1.92) for severe physical abuse compared to none. Compared to women without childhood sexual abuse, the HR was 1.10 (0.88–1.35) for unwanted sexual touching, and 1.56 (1.23–1.99) for forced sex. After adjustment for adult lifestyle and medical risk factors, the HR for severe physical abuse was 1.13 (0.85–1.51) and that for forced sex was 1.25 (0.98–1.60); these intermediates accounted for much of the association of severe child abuse with CVD. Associations were similar for retrospectively and prospectively reported events. Women with abuse were less likely to release medical records. The associations were stronger for unconfirmed self-reported events than endpoints which were corroborated with additional information or medical record review. Conclusions Severe child abuse is a prevalent risk for early adult CVD that is partially mediated by preventable risk factors. PMID:22787111

  3. Education and Income Imbalances Among Married Couples in Malawi as Predictors for Likelihood of Physical and Emotional Intimate Partner Violence.

    PubMed

    Bonnes, Stephanie

    2016-01-01

    Intimate partner violence is a social and public health problem that is prevalent across the world. In many societies, power differentials in relationships, often supported by social norms that promote gender inequality, lead to incidents of intimate partner violence. Among other factors, both a woman's years of education and educational differences between a woman and her partner have been shown to have an effect on her likelihood of experiencing intimate partner abuse. Using the 2010 Malawian Demographic and Health Survey data to analyze intimate partner violence among 3,893 married Malawian women and their husbands, this article focuses on understanding the effect of educational differences between husband and wife on the likelihood of physical and emotional abuse within a marriage. The results from logistic regression models show that a woman's level of education is a significant predictor of her likelihood of experiencing intimate partner violence by her current husband, but that this effect is contingent on her husband's level of education. This study demonstrates the need to educate men alongside of women in Malawi to help decrease women's risk of physical and emotional intimate partner violence. PMID:26645866

  4. Self-Efficacy Beliefs as Predictors of Loneliness and Psychological Distress in Older Adults

    ERIC Educational Resources Information Center

    Fry, Prem S.; Debats, Dominique L.

    2002-01-01

    Sociodemographic variables, social support, and physical health have been used previously in a few predictor models of loneliness and psychological distress in late life. The present study, however, was designed to test the hypothesis that self-efficacy beliefs of elderly persons are significantly stronger predictors of loneliness and…

  5. Physical characteristics as predictors of quadriceps muscle isometric strength: a pilot study.

    PubMed

    Hamzat, T K

    2001-09-01

    This one-group experimental study was carried out to investigate the relationship between isometric strength of quadriceps femoris muscle group and physical characteristics of subjects namely: age; weight; and height. Prediction equations were also derived for quadriceps isometric strength from these physical characteristics. Fifty volunteer, right-legged healthy normal male subjects participated in the study. They were aged between 19 and 27 years. The subjects had no previous history of neuromuscular and skeletal injuries to the lower limbs. Their ages, height and weight were measured in years, centimeters and kilograms, respectively. Quadriceps isometric strength was measured using an adapted cable tensiometer (ACT) and recorded in kilogramforce (kgf). Pearson's product correlation co-efficient (r) was used to study the relationship between quadriceps strength and each of age, height and weight. Linear and multiple regression analyses were also carried out. The result showed a high and positive Pearson's moment correlation coefficient (r) between quadriceps isometric strength and each of weight and height. A positive but low correlation (r) was also found between age and quadriceps isometric strength. Prediction equations were also derived from the linear and regression analyses. The study concluded that there was linear relationship between the physical characteristics and quadriceps isometric strength. It was recommended that the prediction equation be employed to estimate quadriceps strength while setting muscle strengthening goals in the clinics during medical rehabilitation for patients within the age range used in this study. PMID:14510124

  6. Dietary carbohydrates, physical inactivity, obesity, and the 'metabolic syndrome' as predictors of coronary heart disease.

    PubMed

    Liu, S; Manson, J E

    2001-08-01

    Several decades of epidemiological and clinical research have identified physical inactivity, excessive calorie consumption, and excess weight as common risk factors for both type 2 diabetes mellitus and coronary heart disease. This trio forms the environmental substrate for a now well-recognized metabolic phenotype called the insulin resistance syndrome. Recent data suggest that a high intake of rapidly absorbed carbohydrates, which is characterized by a high glycemic load (a measure of carbohydrate quality and quantity), may increase the risk of coronary heart disease by aggravating glucose intolerance and dyslipidemia. These data also suggest that individuals who are obese and insulin resistant are particularly prone to the adverse effects of a high dietary glycemic load. In addition, data continue to accumulate suggesting the important beneficial effects of physical activity, even at moderate levels, and weight reduction on improving insulin sensitivity and reducing the risk of coronary heart disease. Future metabolic studies should continue to quantify the physiological impact of different foods on serum glucose and insulin, and such information should routinely be incorporated into large-scale and long-term prospective studies, in which the possible interaction effects between diet and other metabolic determinants such as physical activity and obesity can be examined. Until more definitive data are available, replacing refined grain products and potatoes with minimally processed plant-based foods such as whole grains, fruits, and vegetables, and reducing the intake of high glycemic load beverages may offer a simple strategy for reducing the incidence of coronary heart disease. PMID:11507324

  7. Predictors of treatment completion in a sample of youth who have experienced physical or sexual trauma.

    PubMed

    Murphy, Robert A; Sink, Holli E; Ake, George S; Carmody, Karen Appleyard; Amaya-Jackson, Lisa M; Briggs, Ernestine C

    2014-01-01

    Despite significant advances in knowledge and availability of evidence-based models for child traumatic stress, many children simply do not complete treatment. There remain notable gaps in the services research literature about treatment completion among youth, particularly those who have experienced trauma and related sequelae. This study investigated the linkages among child physical and sexual trauma, posttraumatic stress disorder (PTSD) symptomatology, and treatment completion utilizing a clinical sample drawn from a large database from community treatment centers across the United States specializing in childhood trauma. Results from regression analyses indicated that neither the experience of sexual nor physical trauma directly predicted successful treatment completion. The links between sexual trauma and treatment completion, however, were mediated by PTSD avoidance symptoms. Children and youth experiencing sexual trauma reported higher levels of avoidance symptoms that were, in turn, significantly associated with a lower likelihood of completing trauma-focused mental health treatment. Practice implications are discussed and include strategies for clinicians to intervene during pivotal points of treatment to improve rates of service utilization and treatment completion. PMID:24084895

  8. Individual and social network predictors of physical bullying: a longitudinal study of Taiwanese early adolescents.

    PubMed

    Wei, Hsi-Sheng; Lee, Wonjae

    2014-01-01

    This study followed 125 7th-grade students in Taiwan for the entire school year and analyzed the individual and social network factors predicting their involvement in physical bullying over 5 waves of data. Using self-reports of bullying experiences, 20 classroom-level networks of bullying and friendship were constructed for 4 classrooms and 5 temporal points, from which 4 individual-level network measures were calculated. They included bully and victim centrality, popularity, and embeddedness in friendship networks. A series of mixed models for repeated measures were constructed to predict students' bully and victim centrality in bullying network at time t + 1. Compared to girls, boys were more likely to be both the bullies and victims. Lower self-esteem and higher family economic status contributed to victim centrality. Having parents married and living together predicted lower bully centrality. Higher educational level of parents predicted lower victim and bully centrality. Regarding the social network factors, students' bully centrality at t positively predicted their bully centrality at t + 1, whereas victim centrality predicted their subsequent victim centrality. Interaction effects between friendship network and bullying network were observed. Embeddedness in friendship network reduced victim centrality at t + 1 except for those students with low victim centrality at t. For those with high victim centrality at t, popularity increased their risk of physical victimization over time. Implications for research and practice are discussed. PMID:25199395

  9. Physical activity, and not fat mass is a primary predictor of circadian parameters in young men.

    PubMed

    Tranel, Hannah R; Schroder, Elizabeth A; England, Jonathan; Black, W Scott; Bush, Heather; Hughes, Michael E; Esser, Karyn A; Clasey, Jody L

    2015-01-01

    Circadian rhythms are ≈24 h oscillations in physiology and behavior, and disruptions have been shown to have negative effects on health. Wrist skin temperature has been used by several groups as a valid method of assessing circadian rhythms in humans. We tested the hypothesis that circadian temperature amplitude (TempAmp) and stability (TempStab) would significantly differ among groups of healthy young men of varying adiposities, and that we could identify physiological and behavioral measures that were significantly associated with these temperature parameters. Wrist skin temperatures taken at 10 min intervals for 7 consecutive days were determined in 18 optimal (OGroup), 20 fair (FGroup) and 21 poor (PGroup) %Fat grouped young men and subsequently analyzed using available validated software. Body composition, cardiorespiratory fitness, actigraphy, daily nutritional and sleep data, and fasting lipid, insulin and glucose concentration measures were also determined. Significant changes in TempAmp and TempStab parameters in subjects with a single metabolic syndrome (MetS) risk factor compared to those with no MetS factors was observed. In addition, stepwise multivariate regression analyses showed that 50% of the variance in TempAmp was explained by actigraphy (mean steps taken per day; MSTPD), cardiorespiratory fitness, and late night eating per week (#LNE); and 57% in TempStab by MSTPD, time spent in moderate-to-vigorous activity per day, fat mass, and #LNE. Overwhelmingly, physical activity was the most important measure associated with the differences in circadian rhythm parameters. Further research is warranted to determine the effects of increasing the amount and timing of physical activity on the status of the circadian system in a variety of populations. PMID:26101893

  10. Bayesian inference for generalized linear mixed models with predictors subject to detection limits: an approach that leverages information from auxiliary variables.

    PubMed

    Yue, Yu Ryan; Wang, Xiao-Feng

    2016-05-10

    This paper is motivated from a retrospective study of the impact of vitamin D deficiency on the clinical outcomes for critically ill patients in multi-center critical care units. The primary predictors of interest, vitamin D2 and D3 levels, are censored at a known detection limit. Within the context of generalized linear mixed models, we investigate statistical methods to handle multiple censored predictors in the presence of auxiliary variables. A Bayesian joint modeling approach is proposed to fit the complex heterogeneous multi-center data, in which the data information is fully used to estimate parameters of interest. Efficient Monte Carlo Markov chain algorithms are specifically developed depending on the nature of the response. Simulation studies demonstrate the outperformance of the proposed Bayesian approach over other existing methods. An application to the data set from the vitamin D deficiency study is presented. Possible extensions of the method regarding the absence of auxiliary variables, semiparametric models, as well as the type of censoring are also discussed. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26643287

  11. Satellite views of Pacific chlorophyll variability: Comparisons to physical variability, local versus nonlocal influences and links to climate indices

    NASA Astrophysics Data System (ADS)

    Thomas, Andrew C.; Ted Strub, P.; Weatherbee, Ryan A.; James, Corinne

    2012-11-01

    Concurrent satellite-measured chlorophyll (CHL), sea surface temperature (SST), sea level anomaly (SLA) and model-derived wind vectors from the 13+ year SeaWiFS period September 1997-December 2010 quantify time and space patterns of phytoplankton variability and its links to physical forcing in the Pacific Ocean. The CHL fields are a metric of biological variability, SST represents vertical mixing and motion, often an indicator of nutrient availability in the upper ocean, SLA is a proxy for pycnocline depths and surface currents while vector winds represent surface forcing by the atmosphere and vertical motions driven by Ekman pumping. Dominant modes of variability are determined using empirical orthogonal functions (EOFs) applied to a nested set of domains for comparison: over the whole basin, over the equatorial corridor, over individual hemispheres at extra-tropical latitudes (>20°) and over eastern boundary current (EBC) upwelling regions. Strong symmetry exists between hemispheres and the EBC regions, both in seasonal and non-seasonal variability. Seasonal variability is strongest at mid latitudes but non-seasonal variability, our primary focus, is strongest along the equatorial corridor. Non-seasonal basin-scale variability is highly correlated with equatorial signals and the strongest signal across all regions in the study period is associated with the 1997-1999 ENSO cycle. Results quantify the magnitude and geographic pattern with which dominant basin-scale signals are expressed in extra-tropical regions and the EBC upwelling areas, stronger in the Humboldt Current than in the California Current. In both EBC regions, wind forcing has weaker connections to non-seasonal CHL variability than SST and SLA, especially at mid and lower latitudes. Satellite-derived dominant physical and biological patterns over the basin and each sub-region are compared to indices that track aspects of climate variability in the Pacific (the MEI, PDO and NPGO). We map and compare

  12. Chemical and Physical Predictors of the Nutritive Value of Wheat in Broiler Diets

    PubMed Central

    Ball, M. E. E.; Owens, B.; McCracken, K. J.

    2013-01-01

    The aim of this study was to establish relationships between chemical and physical parameters of wheat with performance and digestibilities of feed components in broiler chickens fed on wheat-based diets. Ninety-four wheat samples were selected for inclusion in four bird trials. Birds were housed in individual wire metabolism cages from 7 to 28 d and offered water and feed ad libitum. Dry matter intake (DMI), liveweight gain (LWG) and gain:feed were measured weekly. A balance collection was carried out from 14 to 21 d for determination of apparent metabolizable energy (AME), ME:gain, dry matter retention, oil and neutral detergent fibre (NDF) digestibility. At 28 d the birds were humanely killed, the contents of the jejunum removed for determination of in vivo viscosity and the contents of the ileum removed for determination of ileal dry matter, starch and protein digestibility. When wheat parameters were correlated with bird performance data, it was found that specific weight was not significantly (p>0.05) related to bird performance. Bird DMI, LWG and gain:feed were best correlated (p<0.05) with the rate of starch digestion, although the coefficients of correlation (r) were still low (0.246 to 0.523). A negative relationship (p<0.01) between AME and total (r = −0.432) and soluble (r = −0.304) non starch polysaccharide (NSP) was observed in this study. Thousand grain weight (TG) was positively correlated with DMI (r = 0.299), LWG (r = 0.343) and gain:feed (r = 0.371). When establishing multiple regression relationships, correlation coefficients greater than 0.8 were achieved for DMI, LWG, gain:feed and ileal crude protein digestibility. However, the economics involved in determining the parameters involved in the regressions make the process impractical. PMID:25049711

  13. 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…

  14. Antarctic sea ice change and variability - Physical and ecological implications

    NASA Astrophysics Data System (ADS)

    Massom, Robert A.; Stammerjohn, Sharon E.

    2010-08-01

    Although Antarctic sea ice is undergoing a slight increase in overall extent, major regional changes are occurring in its spatio-temporal characteristics (most notably in sea ice seasonality). Biologically significant aspects of Antarctic sea ice are evaluated, emphasising the importance of scale and thermodynamics versus dynamics. Changing sea ice coverage is having major direct and indirect though regionally-dependent effects on ecosystem structure and function, with the most dramatic known effects to date occurring in the West Antarctic Peninsula region. There is mounting evidence that loss of sea ice has affected multiple levels of the marine food web in a complex fashion and has triggered cascading effects. Impacts on primary production, Antarctic krill, fish, marine mammals and birds are assessed, and are both negative and positive. The review includes recent analysis of change/variability in polynyas and fast ice, and also highlights the significance of extreme events (which have paradoxical impacts). Possible future scenarios are investigated in the light of the predicted decline in sea ice by 2100 e.g. increased storminess/waviness, numbers of icebergs and snowfall. Our current lack of knowledge on many aspects of sea ice-related change and biological response is emphasised.

  15. A data-driven approach to develop physically sound predictors: Application to depth-averaged velocities on flows through submerged arrays of rigid cylinders

    NASA Astrophysics Data System (ADS)

    Tinoco, R. O.; Goldstein, E. B.; Coco, G.

    2015-02-01

    We use a machine learning approach to seek an accurate, physically sound predictor, to estimate the mean velocity for open-channel flow when submerged arrays of rigid cylinders (model vegetation) are present. A genetic programming routine is used to find a robust relationship between relevant properties of the model vegetation and flow parameters. We use published data from laboratory experiments covering a broad range of conditions to obtain an equation that matches the performance of other predictors from recent literature in terms of accuracy, while showing a less complex structure. We also investigate how different criteria for data selection, as well as the size of the data set used to train the algorithm, influences the accuracy of the resulting predictors. Our results show that a proper use of Machine-Learning techniques does not only provide empirical correlations, but can yield physically sound models as representative of the physical processes involved. We provide a clear, thorough example of the application of GP, its advantages and shortcomings, to encourage the use of data-driven techniques as part of the data analysis process, and to address common misconceptions of machine learning as simple correlation techniques or physically senseless statistical analysis.

  16. Effects of psychosocial variables in the similarity and interdependence of physical activity levels among adolescent best friend dyads.

    PubMed

    Lopes, Vítor P; Gabbard, Carl; Rodrigues, Luis P

    2016-01-01

    Given that physical activity (PA) tends to decrease with age during adolescence, addressing factors that affect change is important. This study examined the similarity and interdependence of PA as influenced by psychosocial factors among adolescent best friend dyads. A total of 660 adolescents, representing 330 best friend dyads, completed questionnaires with regard to PA, sitting time, perceived exercise benefits and barriers, physical self-perception and social support for PA. Dyads were also identified as reciprocal and non-reciprocal best friends; reciprocal means that both considered each other best friends and non-reciprocal were those in which only one considered the other a best friend. Data were analysed using a hierarchical linear model framework. Results indicated significant similarities between reciprocal best friend dyads for PA and sitting time, and for sitting time in non-reciprocal best friends (P values <.01). Psychosocial variables were associated with PA in reciprocal best friend dyads and with sitting time in reciprocal and non-reciprocal best friend dyads. Best friend gender, regular sports practice of the person, perceived exercise barriers of the best friend and best friend social support were the best predictors for PA. PMID:26238302

  17. Some Aspects of the Physical Variability of the Caribbean Sea Relevant to Regional Climate Variability

    NASA Astrophysics Data System (ADS)

    Mooers, C. N.

    2001-12-01

    The Caribbean Sea is the least studied portion of the Intra-Americas Sea (IAS), which is the combined Caribbean Sea, Gulf of Mexico, Straits of Florida, and the adjacent western North Atlantic. The upstream elements of the Gulf Stream System are the dominant features of the upper ocean circulation in the Caribbean Sea. The Trade Winds superimpose a coastal upwelling regime along the northern coast of South America and a coastal downwelling regime along the southern coasts of Cuba and Hispaniola. The inflow from the Atlantic through several Antillean passages is derived from tropical and subtropical sources and is relatively weak, shallow, and variable; the outflow to the Gulf of Mexico through the Yucatan Channel is relatively strong, deep, and variable. The variability includes mesoscale eddies and meanders as well as the seasonal cycle and year-to-year variability; it also includes lengthy plumes from the Orinoco and other rivers and lengthy filaments from coastal upwelling centers. Some of the mesoscale variability originates in the Eastern Caribbean; other components originate in the Western Caribbean, especially in the cyclonic Panama-Colombia Gyre. The upper ocean of the Caribbean Sea is not only under the influence of the Trade Winds and their seasonal and longer term variability but also two other, not mutually exclusive, sources of variability: the seasonal heating and precipitation cycles on one hand, and synoptic scale and mesoscale phenomena on the other hand. For example, there are wet and dry seasons, and the Eastern Caribbean is typically dry and the Western Caribbean typically wet, with a heavy rainfall zone off the coast of Central America. And the patterns of atmospheric deep convection and subsidence apparently account for the summertime intensification of an extensive "warm pool" concentrated in the Northwestern Caribbean, which is exported to the Gulf of Mexico. As another example, the weekly Tropical Easterly Waves (TEWs) are the predominant

  18. Seasonal and interannual variability of chlorophyll-a and associated physical synchronous variability in the western tropical Pacific

    NASA Astrophysics Data System (ADS)

    Hou, Xueyan; Dong, Qing; Xue, Cunjin; Wu, Shuchao

    2016-06-01

    Based on long-term satellite-derived ocean data sets and methods of empirical orthogonal function and singular value decomposition, we investigated the spatiotemporal variability of the chlorophyll-a concentration (CHL) on seasonal and interannual timescales in the western tropical Pacific associated with physical ocean variables of sea surface temperature (SST), sea level anomaly (SLA) and sea surface wind (SSW), and the El Niño Southern Oscillation (ENSO) index. The bio-physical synchronous variation on interannual timescale was also confirmed in terms of the scales of variability and oscillation periods in the time-frequency space using the methods of Fourier transform, Morlet wavelet transform, and wavelet coherence analysis. On a seasonal timescale, the first two modes of the monthly mean CHL fields described the consecutive spatiotemporal variation in CHL in the western tropical Pacific. CHL reached the maximum during late winter-early spring and minimum during summer-early autumn with the exception of the northeast of Papua New Guinea and the Solomon Islands. The CHL bloom in boreal winter-spring was closely associated with cold SST, high sea level along the North Equatorial Countercurrent meanders, and strong wind. On an interannual timescale, the variability of CHL exhibited a close correlation with SST, SLA, SSW, and ENSO. During El Niño, CHL increased in the oligotrophic western basin of the warm pool associated with cold SST, low SLA, and strong westerly winds but decreased in the mesotrophic eastern basin of the warm pool in association with warm SST, high SLA, and weak easterly trade winds. There may exist time-lag for the bio-physical covariation, i.e., CHL and SST varied simultaneously within 1 month, and CHL variations led SLA by approximately 0-3 months but lagged wind speed by about 1 month. In the time-frequency domain, the interannual variability in CHL and physical ocean variables had high common power, indicating that the variability scales

  19. Physical mechanisms of solar variability influence on weather and climate

    NASA Astrophysics Data System (ADS)

    Avakyan, Sergei

    2010-05-01

    Numerous researches into correlation of weather and climate characteristics with solar and geomagnetic activity confirm that such correlation does exist. However there is some uncertainty in interpretation of the Sun-weather-climate relations. The paper considers the main causes of this uncertainty which are as follows - the lack of permanent monitoring data on ionizing solar EUV/X-ray radiation including periods of flares; and also the data on electron fluxes of keV energy precipitating from radiation belts first of all during geomagnetic storms; - multiplicity of Sun-weather-climate links; - the lack of understanding what are the mechanisms of solar-geomagnetic activity (flares and storms) influence on weather and climate characteristics; By now mainly the research on galactic cosmic rays (GSR) including Forbush effects and solar cosmic rays (SCR) influences on atmosphere transparence characteristics and further on climate-weather characteristics have been carried out. The GCR flux increase causes the growth of low (usually optically thick) cloudness and therefore produces in generally cooling effect on the mean surface air temperature. The appearance of SCR causes the reduction of stratospheric and tropospheric transparence and produces also usually cooling effect However these events are rare and corresponding variations of fluxes energy are small. At the same time such strong and frequent manifestations of solar activity as flares and magnetic storms are not so far taken into account since it is not known what physical mechanisms could be responsible for energy transfer from solar flares and magnetic storms to the lower atmosphere. The paper describes a novel radio-optical mechanism responsible for the solar-terrestrial links which acts as a three-stage trigger and which could be useful for solving the problem "Sun- weather-climate". This physical mechanism is based on taking into account the excitation of Rydberg states of atoms and molecules in generation of

  20. Physical Aggression in Early Marriage: Prerelationship and Relationship Effects.

    ERIC Educational Resources Information Center

    O'Leary, K. Daniel; And Others

    1994-01-01

    Predicted spousal physical aggression at 30 months after marriage for 393 young couples. Prerelationship predictor variables were history of violence in family of origin, aggression against others during childhood and adolescence, and personality characteristics. Relationship predictor variables were marital discord and spouse-specific…

  1. Movement Variability and the Use of Nonlinear Tools: Principles to Guide Physical Therapist Practice

    PubMed Central

    Harbourne, Regina T; Stergiou, Nicholas

    2009-01-01

    Fields studying movement generation, including robotics, psychology, cognitive science, and neuroscience, utilize concepts and tools related to the pervasiveness of variability in biological systems. The concepts of variability and complexity and the nonlinear tools used to measure these concepts open new vistas for physical therapist practice and research in movement dysfunction of all types. Because mounting evidence supports the necessity of variability for health and functional movement, this perspective article argues for changes in the way therapists view variability, both in theory and in action. By providing clinical examples, as well as applying existing knowledge about complex systems, the aim of this article is to create a springboard for new directions in physical therapist research and practice. PMID:19168711

  2. 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.

  3. Sources and magnitude of variability in pedometer-determined physical activity levels of youth

    PubMed Central

    Kim, So-Yeun; Park, Hye-Sang

    2015-01-01

    This study examined sources of variability in habitual physical activity of children, and the minimum number of days required for estimating children’s habitual physical activity levels using pedometers. A total of 31 children wore two pedometers during five weekdays and four weekend days. A two random facet completely crossed design was conducted with two-way analysis of variances across weekdays, weekends, and weekdays and weekend days combined. Moderate/high generalizability coefficients were estimated across all days. Primary sources of variability were variance components of the person and person by day interaction. Minimum numbers of days required for estimating habitual physical activity levels using a pedometer were five during weekdays. However, estimating habitual physical activity levels during weekends, and weekdays and weekend days combined was impractical. PMID:26730388

  4. 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

  5. Personality Variables as Predictors of Leadership Role Performance Effectiveness of Administrators of Public Secondary Schools in Cross River State, Nigeria

    ERIC Educational Resources Information Center

    Akpan, Charles P.; Archibong, Ijeoma A.

    2012-01-01

    The study sought to find out the predictive effect of self-concept, self-efficacy, self-esteem and locus of control on the instructional and motivational leadership roles performance effectiveness of administrators of public secondary schools in Cross River State of Nigeria. The relative contribution of each of the independent variables to the…

  6. Predictors of International Graduate Student Success in U.S. Universities: Analysis of Noncognitive Student Variables and Institutional Characteristics

    ERIC Educational Resources Information Center

    Sanford, Rania

    2009-01-01

    Purpose. The purpose of this study was to determine the relationships between Sedlacek's (2004b) student noncognitive variables (positive self-concept, realistic self-appraisal, successfully handling the system, preference for long-term goals, leadership experience, presence of a strong support person, community service, and knowledge of the…

  7. College BASE versus American College Testing as a Predictor Variable for National Teacher's Examination and Grade Point Average.

    ERIC Educational Resources Information Center

    Osterlind, Steven J.; Schmitz, Charles D.

    1993-01-01

    Investigated differences in robustness of two independent variables for predicting National Teacher Examinations (NTE) scores and grade point averages (GPAs) for college seniors and recent graduates (n=1,441). By every method of analysis, data clearly indicated superiority of College Basic Academic Subjects Examination over American College…

  8. Social desirability is associated with some physical activity, psychosocial variables and sedentary behavior but not self-reported physical activity among adolescent males

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined whether controlling for social desirability improved the association between self-reported and objectively measured physical activity among adolescent males and the extent that psychosocial variables predict physical activity after controlling for social desirability. Participant...

  9. Childhood Emotional Abuse and Neglect as Predictors of Psychological and Physical Symptoms in Women Presenting to a Primary Care Practice

    ERIC Educational Resources Information Center

    Spertus, Ilyse L.; Yehuda, Rachel; Wong, Cheryl M.; Halligan, Sarah; Seremetis, Stephanie V.

    2003-01-01

    Objective: There were two aims to this study: first to examine whether emotional abuse and neglect are significant predictors of psychological and somatic symptoms, and lifetime trauma exposure in women presenting to a primary care practice, and second to examine the strength of these relationships after controlling for the effects of other types…

  10. A statistical-dynamical scheme for reconstructing ocean forcing in the Atlantic. Part I: weather regimes as predictors for ocean surface variables

    NASA Astrophysics Data System (ADS)

    Cassou, Christophe; Minvielle, Marie; Terray, Laurent; Périgaud, Claire

    2011-01-01

    The links between the observed variability of the surface ocean variables estimated from reanalysis and the overlying atmosphere decomposed in classes of large-scale atmospheric circulation via clustering are investigated over the Atlantic from 1958 to 2002. Daily 500 hPa geopotential height and 1,000 hPa wind anomaly maps are classified following a weather-typing approach to describe the North Atlantic and tropical Atlantic atmospheric dynamics, respectively. The algorithm yields patterns that correspond in the extratropics to the well-known North Atlantic-Europe weather regimes (NAE-WR) accounting for the barotropic dynamics, and in the tropics to wind classes (T-WC) representing the alteration of the trades. 10-m wind and 2-m temperature (T2) anomaly composites derived from regime/wind class occurrence are indicative of strong relationships between daily large-scale atmospheric circulation and ocean surface over the entire Atlantic basin. High temporal correlation values are obtained basin-wide at low frequency between the observed fields and their reconstruction by multiple linear regressions with the frequencies of occurrence of both NAE-WR and T-WC used as sole predictors. Additional multiple linear regressions also emphasize the importance of accounting for the strength of the daily anomalous atmospheric circulation estimated by the combined distances to all regimes centroids in order to reproduce the daily to interannual variability of the Atlantic ocean. We show that for most of the North Atlantic basin the occurrence of NAE-WR generally sets the sign of the ocean surface anomaly for a given day, and that the inter-regime distances are valuable predictors for the magnitude of that anomaly. Finally, we provide evidence that a large fraction of the low-frequency trends in the Atlantic observed at the surface over the last 50 years can be traced back, except for T2, to changes in occurrence of tropical and extratropical weather classes. All together, our

  11. Improvements made to simulated tropical variability in climate models by stochastic physics

    NASA Astrophysics Data System (ADS)

    Watson, Peter; Palmer, Tim

    2016-04-01

    Many climate models have too little variability in the tropics on daily to weekly time scales. This degrades their ability to simulate extreme events and how they will change with global warming. Stochastic parameterisations, which include a physically-based representation of the uncertainty in unresolved processes, have the potential to alleviate this problem by including variability associated with unresolved processes that is left out of deterministic models. The stochastic physics scheme used operationally by ECMWF has been shown to increase their weather forecast skill. Here we show that in an atmospheric GCM, the scheme makes the simulated tropical variability more consistent with observations by increasing daily precipitation variance, reducing its autocorrelation, and increasing the frequency of heavy-rainfall events. Stochastic physics may therefore be important for improving the model simulations and predicting how the statistics of extreme tropical events will change in the future. We also show also that even when the model's horizontal resolution is increased to that of a weather forecast model, there is still too little simulated tropical variability, so stochastic physics is likely to remain important even as computational power increases.

  12. Management Practices and Landscape Variability Effects on Selected Soil Physical Properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the spatial variability of soil physical properties is important for aiding in the recommendation and implementation of site-specific crop management. As a soil-forming factor, topography leads to soil differentiation because of variations in water infiltration and depth to water table...

  13. Ethnic Variables and Negative Life Events as Predictors of Depressive Symptoms and Suicidal Behaviors in Latino College Students: On the Centrality of "Receptivo a los Demás"

    ERIC Educational Resources Information Center

    Chang, Edward C.; Yu, Elizabeth A.; Yu, Tina; Kahle, Emma R.; Hernandez, Viviana; Kim, Jean M.; Jeglic, Elizabeth L.; Hirsch, Jameson K.

    2016-01-01

    In the present study, we examined ethnic variables (viz., multigroup ethnic identity and other group orientation) along with negative life events as predictors of depressive symptoms and suicidal behaviors in a sample of 156 (38 male and 118 female) Latino college students. Results of conducting hierarchical regression analyses indicated that the…

  14. Process monitoring using automatic physical measurement based on electrical and physical variability analysis

    NASA Astrophysics Data System (ADS)

    Shauly, Eitan N.; Levi, Shimon; Schwarzband, Ishai; Adan, Ofer; Latinsky, Sergey

    2015-04-01

    A fully automated silicon-based methodology for systematic analysis of electrical features is shown. The system was developed for process monitoring and electrical variability reduction. A mapping step was created by dedicated structures such as static-random-access-memory (SRAM) array or standard cell library, or by using a simple design rule checking run-set. The resulting database was then used as an input for choosing locations for critical dimension scanning electron microscope images and for specific layout parameter extraction then was input to SPICE compact modeling simulation. Based on the experimental data, we identified two items that must be checked and monitored using the method described here: transistor's sensitivity to the distance between the poly end cap and edge of active area (AA) due to AA rounding, and SRAM leakage due to a too close N-well to P-well. Based on this example, for process monitoring and variability analyses, we extensively used this method to analyze transistor gates having different shapes. In addition, analysis for a large area of high density standard cell library was done. Another set of monitoring focused on a high density SRAM array is also presented. These examples provided information on the poly and AA layers, using transistor parameters such as leakage current and drive current. We successfully define "robust" and "less-robust" transistor configurations included in the library and identified unsymmetrical transistors in the SRAM bit-cells. These data were compared to data extracted from the same devices at the end of the line. Another set of analyses was done to samples after Cu M1 etch. Process monitoring information on M1 enclosed contact was extracted based on contact resistance as a feedback. Guidelines for the optimal M1 space for different layout configurations were also extracted. All these data showed the successful in-field implementation of our methodology as a useful process monitoring method.

  15. Day/Night Variability in Blood Pressure: Influence of Posture and Physical Activity

    PubMed Central

    2013-01-01

    BACKGROUND Blood pressure (BP) is highest during the day and lowest at night. Absence of this rhythm is a predictor of cardiovascular morbidity and mortality. Contributions of changes in posture and physical activity to the 24-hour day/night rhythm in BP are not well understood. We hypothesized that postural changes and physical activity contribute substantially to the day/night rhythm in BP. METHODS Fourteen healthy, sedentary, nonobese, normotensive men (aged 19–50 years) each completed an ambulatory and a bed rest condition during which BP was measured every 30–60 minutes for 24 hours. When ambulatory, subjects followed their usual routines without restrictions to capture the “normal” condition. During bed rest, subjects were constantly confined to bed in a 6-degree head-down position; therefore posture was constant, and physical activity was minimized. Two subjects were excluded from analysis because of irregular sleep timing. RESULTS The systolic and diastolic BP reduction during the sleep period was similar in ambulatory (−11±2mmHg/−8±1mmHg) and bed rest conditions (−8±3mmHg/−4±2mmHg; P = 0.38/P = 0.12). The morning surge in diastolic BP was attenuated during bed rest (P = 0.001), and there was a statistical trend for the same effect in systolic BP (P = 0.06). CONCLUSIONS A substantial proportion of the 24-hour BP rhythm remained during bed rest, indicating that typical daily changes in posture and/or physical activity do not entirely explain 24-hour BP variation under normal ambulatory conditions. However, the morning BP increase was attenuated during bed rest, suggesting that the adoption of an upright posture and/or physical activity in the morning contributes to the morning BP surge. PMID:23535155

  16. Heart period variability and respiratory changes associated with physical and mental load: non-linear analysis.

    PubMed

    Sammer, G

    1998-05-01

    In the investigation of heart rate and heart rate variability, the discrimination between mental workload, physical activity and respiration is known to be methodologically difficult. At most, heart rate variability measures are more likely to be coarse-grained measures with variability confounded by heart rate. Moreover, the spectral analysis of heart rate variability shows broad-band frequency characteristics, pointing towards non-stationarity or non-linearity. From this it is suggested to focus on non-linear dynamic analyses that are variance-insensitive. The experimental section of the paper focuses on the estimation of two non-linear measures for both heartbeat dynamics and respiration, the correlation dimension indicating complexity and the Lyapunov exponents indicating predictability. The results indicate that the complexity of heart dynamics is related to the type of task and that the predictability of heart dynamics is related to the amount of load. PMID:9613233

  17. Variables associated with children's physical activity levels during recess: the A-CLASS project

    PubMed Central

    2010-01-01

    Background School recess provides a daily opportunity for children to engage in physically active behaviours. However, few studies have investigated what factors may influence children's physical activity levels in this context. Such information may be important in the development and implementation of recess interventions. The aim of this study was to investigate the association between a range of recess variables and children's sedentary, moderate and vigorous physical activity in this context. Methods One hundred and twenty-eight children (39% boys) aged 9-10 years old from 8 elementary schools had their physical activity levels observed during school recess using the System for Observing Children's Activity and Relationships during Play (SOCARP). Playground variables data were also collected at this time. Multilevel prediction models identified variables that were significantly associated with children's sedentary, moderate and vigorous physical activity during recess. Results Girls engaged in 13.8% more sedentary activity and 8.2% less vigorous activity than boys during recess. Children with no equipment provision during recess engaged in more sedentary activity and less moderate activity than children provided with equipment. In addition, as play space per child increased, sedentary activity decreased and vigorous activity increased. Temperature was a significant negatively associated with vigorous activity. Conclusions Modifiable and unmodifiable factors were associated with children's sedentary, moderate and vigorous physical activity during recess. Providing portable equipment and specifying areas for activities that dominate the elementary school playground during recess may be two approaches to increase recess physical activity levels, though further research is needed to evaluate the short and long-term impact of such strategies. PMID:20937142

  18. Early and current physical activity: relationship with intima-media thickness and metabolic variables in adulthood.

    PubMed

    Lima, Manoel C S; Barbosa, Maurício F; Diniz, Tiego A; Codogno, Jamile S; Freitas Júnior, Ismael F; Fernandes, Rômulo A

    2014-08-29

    Background: It is unclear whether early physical activity has a greater influence on intima-media thickness and metabolic variables than current physical activity. Objective: To analyze the relationship between current and early physical activity, metabolic variables, and intima-media thickness measures in adults. Method: The sample was composed of 55 healthy subjects of both sexes (33 men and 22 women). Total body fat and trunk fat were estimated by dual-energy X-ray absorptiometry. Carotid and femoral intima-media thickness were measured using a Doppler ultrasound device. A 12-hour fasting blood sample collection was taken (fasting glucose and lipid profile). Early physical activity was assessed through face-to-face interview, and the current physical activity was assessed by pedometer (Digi-Walker Yamax, SW200), which was used for a period of seven days. Results: Current physical activity was negatively related to total cholesterol (rho=-0.31), while early physical activity was negatively related to triglycerides (rho=-0.42), total cholesterol (rho=-0.28), very low density lipoprotein (rho=-0.44), and carotid intima-media thickness (rho=-0.50). In the multivariate model, subjects engaged in sports activities during early life had lower values of very low density lipoprotein (b=-8.74 [b=-16.1; -1.47]) and carotid intima-media thickness (b=-0.17 [95%CI: -0.28; -0.05]). Conclusion: Early 95%CI physical activity has a significant influence on carotid intima-media thickness, regardless of the current physical activity. PMID:25185030

  19. Early and current physical activity: relationship with intima-media thickness and metabolic variables in adulthood

    PubMed Central

    Lima, Manoel C. S.; Barbosa, Maurício F.; Diniz, Tiego A.; Codogno, Jamile S.; Freitas, Ismael F.; Fernandes, Rômulo A.

    2014-01-01

    Background: It is unclear whether early physical activity has a greater influence on intima-media thickness and metabolic variables than current physical activity. Objective: To analyze the relationship between current and early physical activity, metabolic variables, and intima-media thickness measures in adults. Method: The sample was composed of 55 healthy subjects of both sexes (33 men and 22 women). Total body fat and trunk fat were estimated by dual-energy X-ray absorptiometry. Carotid and femoral intima-media thickness were measured using a Doppler ultrasound device. A 12-hour fasting blood sample collection was taken (fasting glucose and lipid profile). Early physical activity was assessed through face-to-face interview, and the current physical activity was assessed by pedometer (Digi-Walker Yamax, SW200), which was used for a period of seven days. Results: Current physical activity was negatively related to total cholesterol (rho=-0.31), while early physical activity was negatively related to triglycerides (rho=-0.42), total cholesterol (rho=-0.28), very low density lipoprotein (rho=-0.44), and carotid intima-media thickness (rho=-0.50). In the multivariate model, subjects engaged in sports activities during early life had lower values of very low density lipoprotein (b=-8.74 [b=-16.1; -1.47]) and carotid intima-media thickness (b=-0.17 [95%CI: -0.28; -0.05]). Conclusion: Early 95%CI physical activity has a significant influence on carotid intima-media thickness, regardless of the current physical activity. PMID:25372009

  20. Modelling stochastic variability and uncertainty in aroma active compounds of PEF-treated peach nectar as a function of physical and sensory properties, and treatment time.

    PubMed

    Evrendilek, Gulsun Akdemir; Avsar, Yahya Kemal; Evrendilek, Fatih

    2016-01-01

    Effects of pulsed electric field (PEF) processing on 28 aroma active compounds, and four physical and eight sensory properties of peach nectar were explored using the best-fit multiple linear regression (MLR) models and Monte Carlo simulations as a function of the treatment times of 0, 66, 131, and 210 μs. The PEF treatment time of 131 μs on average led consistently to the least loss of most compounds. Significantly enhanced or no significant changes in the sensory properties were found as a function of the PEF treatment times. The most influential sensory predictor of the 28 MLR models was flavour, while the aroma compound most influential on the sensory properties of aftertaste, flavour, sweetness, and overall acceptance was octadecanoic acid. Monte Carlo simulations were used for the probabilistic assessments of stochastic variability and uncertainty associated with aroma active compounds of PEF-treated peach nectar. PMID:26213021

  1. Ranking of predictor variables based on effect size criterion provides an accurate means of automatically classifying opinion column articles

    NASA Astrophysics Data System (ADS)

    Legara, Erika Fille; Monterola, Christopher; Abundo, Cheryl

    2011-01-01

    We demonstrate an accurate procedure based on linear discriminant analysis that allows automatic authorship classification of opinion column articles. First, we extract the following stylometric features of 157 column articles from four authors: statistics on high frequency words, number of words per sentence, and number of sentences per paragraph. Then, by systematically ranking these features based on an effect size criterion, we show that we can achieve an average classification accuracy of 93% for the test set. In comparison, frequency size based ranking has an average accuracy of 80%. The highest possible average classification accuracy of our data merely relying on chance is ∼31%. By carrying out sensitivity analysis, we show that the effect size criterion is superior than frequency ranking because there exist low frequency words that significantly contribute to successful author discrimination. Consistent results are seen when the procedure is applied in classifying the undisputed Federalist papers of Alexander Hamilton and James Madison. To the best of our knowledge, the work is the first attempt in classifying opinion column articles, that by virtue of being shorter in length (as compared to novels or short stories), are more prone to over-fitting issues. The near perfect classification for the longer papers supports this claim. Our results provide an important insight on authorship attribution that has been overlooked in previous studies: that ranking discriminant variables based on word frequency counts is not necessarily an optimal procedure.

  2. Biological-Physical Coupling in the Gulf of Maine: Satellite and Model Studies of Phytoplankton Variability

    NASA Technical Reports Server (NTRS)

    Thomas, Andrew C.; Chai, F.; Townsend, D. W.; Xue, H.

    2002-01-01

    The goals of this project were to acquire, process, QC, archive and analyze SeaWiFS chlorophyll fields over the Gulf of Maine and Scotia Shelf region. The focus of the analysis effort was to calculate and quantify seasonality and interannual. variability of SeaWiFS-measured phytoplankton biomass in the study area and compare these to physical forcing and hydrography. An additional focus within this effort was on regional differences within the heterogeneous biophysical regions of the Gulf of Maine / Scotia Shelf. Overall goals were approached through the combined use of SeaWiFS and AVHRR data and the development of a coupled biology-physical numerical model.

  3. 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.

  4. The Effects of Basic Gymnastics Training Integrated with Physical Education Courses on Selected Motor Performance Variables

    ERIC Educational Resources Information Center

    Alpkaya, Ufuk

    2013-01-01

    The purpose of this study is to determine the influence of gymnastics training integrated with physical education courses on selected motor performance variables in seven year old girls. Subjects were divided into two groups: (1) control group (N=15, X=7.56 plus or minus 0.46 year old); (2) gymnastics group (N=16, X=7.60 plus or minus 0.50 year…

  5. An RCM multi-physics ensemble over Europe: multi-variable evaluation to avoid error compensation

    NASA Astrophysics Data System (ADS)

    García-Díez, Markel; Fernández, Jesús; Vautard, Robert

    2015-12-01

    Regional Climate Models are widely used tools to add detail to the coarse resolution of global simulations. However, these are known to be affected by biases. Usually, published model evaluations use a reduced number of variables, frequently precipitation and temperature. Due to the complexity of the models, this may not be enough to assess their physical realism (e.g. to enable a fair comparison when weighting ensemble members). Furthermore, looking at only a few variables makes difficult to trace model errors. Thus, in many previous studies, these biases are described but their underlying causes and mechanisms are often left unknown. In this work the ability of a multi-physics ensemble in reproducing the observed climatologies of many variables over Europe is analysed. These are temperature, precipitation, cloud cover, radiative fluxes and total soil moisture content. It is found that, during winter, the model suffers a significant cold bias over snow covered regions. This is shown to be related with a poor representation of the snow-atmosphere interaction, and is amplified by an albedo feedback. It is shown how two members of the ensemble are able to alleviate this bias, but by generating a too large cloud cover. During summer, a large sensitivity to the cumulus parameterization is found, related to large differences in the cloud cover and short wave radiation flux. Results also show that small errors in one variable are sometimes a result of error compensation, so the high dimensionality of the model evaluation problem cannot be disregarded.

  6. A physically meaningful equivalent circuit network model of a lithium-ion battery accounting for local electrochemical and thermal behaviour, variable double layer capacitance and degradation

    NASA Astrophysics Data System (ADS)

    von Srbik, Marie-Therese; Marinescu, Monica; Martinez-Botas, Ricardo F.; Offer, Gregory J.

    2016-09-01

    A novel electrical circuit analogy is proposed modelling electrochemical systems under realistic automotive operation conditions. The model is developed for a lithium ion battery and is based on a pseudo 2D electrochemical model. Although cast in the framework familiar to application engineers, the model is essentially an electrochemical battery model: all variables have a direct physical interpretation and there is direct access to all states of the cell via the model variables (concentrations, potentials) for monitoring and control systems design. This is the first Equivalent Circuit Network -type model that tracks directly the evolution of species inside the cell. It accounts for complex electrochemical phenomena that are usually omitted in online battery performance predictors such as variable double layer capacitance, the full current-overpotential relation and overpotentials due to mass transport limitations. The coupled electrochemical and thermal model accounts for capacity fade via a loss in active species and for power fade via an increase in resistive solid electrolyte passivation layers at both electrodes. The model's capability to simulate cell behaviour under dynamic events is validated against test procedures, such as standard battery testing load cycles for current rates up to 20 C, as well as realistic automotive drive cycle loads.

  7. Intra-Individual Variability of Physical Activity in Older Adults With and Without Mild Alzheimer’s Disease

    PubMed Central

    Hoffman, Lesa; Templin, Jonathan

    2016-01-01

    Physical activity shows promise for protection against cognitive decline in older adults with and without Alzheimer’s disease (AD). To better understand barriers to adoption of physical activity in this population, a clear understanding of daily and weekly activity patterns is needed. Most accelerometry studies report average physical activity over an entire wear period without considering the potential importance of the variability of physical activity. This study evaluated individual differences in the amount and intra-individual variability of physical activity and determined whether these differences could be predicted by AD status, day of wear, age, gender, education, and cardiorespiratory capacity. Physical activity was measured via accelerometry (Actigraph GT3X+) over one week in 86 older adults with and without AD (n = 33 and n = 53, respectively). Mixed-effects location-scale models were estimated to evaluate and predict individual differences in the amount and intra-individual variability of physical activity. Results indicated that compared to controls, participants with AD averaged 21% less activity, but averaged non-significantly greater intra-individual variability. Women and men averaged similar amounts of physical activity, but women were significantly less variable. The amount of physical activity differed significantly across days of wear. Increased cardiorespiratory capacity was associated with greater average amounts of physical activity. Investigation of individual differences in the amount and intra-individual variability of physical activity provided insight into differences by AD status, days of monitor wear, gender, and cardiovascular capacity. All individuals regardless of AD status were equally consistent in their physical activity, which may have been due to a highly sedentary sample and/or the early disease stage of those participants with AD. These results highlight the value of considering individual differences in both the amount

  8. Spatio-Temporal Variability in Fecal Indicator Bacteria Concentrations at Huntington Beach: Connections to Physical Forcing

    NASA Astrophysics Data System (ADS)

    Rippy, M. A.; Feddersen, F.; Leichter, J.; Omand, M.; Moore, D. F.; McGee, C.; Franks, P. J.

    2007-05-01

    Two major factors determine the spatial and temporal distributions of fecal indicator bacteria (FIB) at a given beach: local circulation & mixing patterns, and bacterial inactivation rates. High frequency and spatial resolution bacterial sampling combined with measurements of physical processes can be used to infer inactivation rates, enabling differentiation between dilution & mortality as factors driving variability in nearshore FIB abundance. A FIB sampling experiment (HB06) took place on 16 October 2006, at Huntington State Beach, a site selected due to its persistent problems with FIB pollution. Water samples were taken at 20-minute intervals (from 6:50am to 11:50am) at ten locations; four in an alongshore transect spanning 1 km at the shoreline, and the remainder in a 300-m long cross-shore transect. All samples were analyzed for FIB concentration (Total Coliforms, E. coli & Enterococci) and, for a subset, species level Enterococcus composition was determined. As part of the HB06 experiment, currents, temperature, waves, and chlorophyll fluorescence were measured simultaneously in the cross-shore direction with rapid CTD casts 300 m offshore. Results indicate that E. coli and Enterococcus concentrations exhibit exponential decreases with time, with smaller decay rates associated with depth and with sites in the Talbert Marsh and Santa Ana River. FIB concentrations are also noticeably lower farther offshore (300 m). Spatio-temporal patterns in FIB concentration will be presented in conjunction with the nearshore physical data allowing the relationship between physical dynamics and biological variability to be addressed.

  9. Predictors of Meeting Physical Activity and Fruit and Vegetable Recommendations in 9-11-Year-Old Children

    ERIC Educational Resources Information Center

    Beck, Jimikaye; De Witt, Peter; McNally, Janise; Siegfried, Scott; Hill, James O; Stroebele-Benschop, Nanette

    2015-01-01

    Objective: Childhood obesity represents a significant public health problem. This study examined physical activity and nutrition behaviours and attitudes of 9-11-year-olds, and factors influencing these behaviours. Design: Study participants recorded pedometer steps for 7 days and completed physical activity enjoyment, food attitudes and food…

  10. Health Promotion Efforts as Predictors of Physical Activity in Schools: An Application of the Diffusion of Innovations Model

    ERIC Educational Resources Information Center

    Glowacki, Elizabeth M.; Centeio, Erin E.; Van Dongen, Daniel J.; Carson, Russell L.; Castelli, Darla M.

    2016-01-01

    Background: Implementing a comprehensive school physical activity program (CSPAP) effectively addresses public health issues by providing opportunities for physical activity (PA). Grounded in the Diffusion of Innovations model, the purpose of this study was to identify how health promotion efforts facilitate opportunities for PA. Methods: Physical…

  11. Clinical predictors of functioning in persons with acquired immunodeficiency syndrome.

    PubMed

    Wilson, I B; Cleary, P D

    1996-06-01

    To help clinicians better assess and treat functional disabilities in persons with acquired immunodeficiency syndrome (AIDS), the authors estimate empirical relations among biologic and physiologic variables, symptoms, and physical functioning in persons with AIDS. The sample of 305 persons with AIDS for this cross-sectional analysis came from three sites in Boston, Massachusetts: a hospital-based group practice, a human immunodeficiency virus clinic at a city hospital, and a staff-model health maintenance organization. Physical functioning, 10 AIDS-specific symptoms, and mental health were assessed by interview. Clinical diagnoses, comorbidities, health habits such as smoking, laboratory results, and selected medication use were assessed by chart review. Significant predictors of physical functioning P < 0.01, R2 = .58) in a multivariable regression model included energy/fatigue, neurologic symptoms, fever symptoms, a lower hemoglobin level, and current non-pneumonia bacterial infection. Ninety-six percent of the explained variance in physical functioning was accounted for by three symptom complexes: energy/fatigue, neurologic symptoms, and fever symptoms. Significant predictors of energy/fatigue in multivariable models included poorer mental health, lower white blood cell count, longer time since diagnosis, and weight loss (P < 0.01, R2 =.36). Significant predictors of neurologic symptoms included poorer mental health, weight loss, and no zidovudine use (P < 0.001, R2 = .30). Predictors of fever symptoms included poorer mental health, no zidovudine use, weight loss, and history of asthma or chronic obstructive pulmonary disease (P < 0.05, R2 = .25). In conclusion, symptom reports were strong predictors of physical functioning. Poorer mental health and weight loss were correlated consistently with worse symptoms, and not using zidovudine was correlated with worse neurologic and fever symptoms. These variables, and the others the authors identified, may represent

  12. On the observed hysteresis in field-scale soil moisture variability and its physical controls

    NASA Astrophysics Data System (ADS)

    Mascaro, G.; Vivoni, E. R.

    2016-08-01

    The spatiotemporal variability of soil moisture (θ) has rarely been studied at the field scale across different seasons and sites. Here, we utilized 9 months of θ data in two semiarid ecosystems of North America to investigate the key relationship between the spatial mean (<θ>) and standard deviation (σ θ ) at the field-scale (∼100 m). Analyses revealed a strong seasonal control on the σ θ versus <θ> relation and the existence of hysteretic cycles where wetting and dry-down phases have notably different behavior. Empirical orthogonal functions (EOFs) showed that θ variability depends on two dominant spatial patterns, with time-stable and seasonally varying contributions in time, respectively. Correlations between EOFs and land surface properties also indicated that θ patterns are linked to vegetation (terrain and soil) factors at the site with higher (lower) vegetation cover. These physical controls explained the observed hysteresis cycles, thus confirming interpretations from previous modeling studies for the first time.

  13. Coherence of heart rate variability and local physical fields in monitoring studies

    NASA Astrophysics Data System (ADS)

    Tuzhilkin, D. A.; Borodin, A. S.

    2015-11-01

    Technological advances have led to a substantial modification of the physical fields of the environment, which could affect the status of living organisms under their constant exposure. In this study, the activity of human cardiovascular system under the influence of a complex natural physical environmental factors investigated. The study was conducted on a representative homogeneous sample (44 persons aged 19 to 22 years) by simultaneous monitoring of electrocardiograms and natural physical fields in Tomsk (geomagnetic field, meteorological parameters - temperature, pressure and humidity, surface wind speed, the parameters of the Schumann resonance - amplitude, frequency and quality factor of the first four modes in the range of 6 to 32 Hz, the power spectral density infrasonic background in the range of from 0,5 to 32 Hz). It was shown that among the set of parameters of physical fields present field that can resonate in the functioning of the human organism. The greatest coherence with heart rate variability detect variations eastern component of the geomagnetic field.

  14. Identifying predictors of survey mode preference.

    PubMed

    Smyth, Jolene D; Olson, Kristen; Millar, Morgan M

    2014-11-01

    To increase the likelihood of response, many survey organizations attempt to provide sample members with a mode they are thought to prefer. Mode assignment is typically based on conventional wisdom or results from mode choice studies that presented only limited options. In this paper we draw heavily on research and theory from the mode effects and the survey participation literatures to develop a framework for understanding what characteristics should predict mode preferences. We then test these characteristics using data from two different surveys. We find that measures of familiarity with and access to a mode are the strongest predictors of mode preference and measures of safety concerns, physical abilities, and normative concerns are unexpectedly weak predictors. Our findings suggest that variables that may exist on sample frames can be used to inform the assignment of "preferred" modes to sample members. PMID:25131280

  15. 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

    2016-04-01

    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.

  16. Temporal Variability of Physical Properties on an Aquic Argiudoll under no Tillage

    NASA Astrophysics Data System (ADS)

    Castiglione, M. G.; Sasal, M. C.; Wilson, M. G.; Paz González, A.; Oszust, J. D.

    2012-04-01

    Practices for the implementation and development of crops affect soil properties and processes in space and time with consequences for the accumulation and movement of water, nutrients and pollutants, which affects plant growth. The aim of this study was to determine the temporal variability of soil physical properties and its link with the infiltration process, on an Aquic Argiudoll of the Argentine Pampas under no-till cultivation. Sampling was performed during six dates in the INTA EEA Paraná (Entre Ríos, Argentina), in the course of the succession of wheat/ soybean-corn. In each of those dates, rain simulations were performed under covered and uncovered soil. From these results it was determined the saturated hydraulic conductivity (Ks), the runoff coefficient (EC), the accumulated rainfall up to ponding (Tp), the accumulated rainfall to reach the steady state infiltration rate (TI) and the decline slope of the infiltration rate (Pd). Also we determine: the initial soil water content (HI), bulk density (Dap), volume occupied by pores larger than 50 µm (> 50), volume occupied by pores between 10 and 50 µm (10-50), soil physical quality index (S) and structural stability (CDMP). On three dates HI was approximately 11%, two were between 22 and 27% and in the remaining time HI was 36%. Despite these variations we don't observed significant changes in most soil physical properties associated with the structure and pore size. However, we could prove significant differences between dates in Ks and EC, both on bare and cover soil. At the same time, differences in these parameters between coverage degrees were significant only in two dates. The HI affected the variability of Ks results. Also Ks ratio between covered and uncovered soil improved with HI increment, except for HI equal to 36%. We found highly significant linkage between Ks, CE and Pd with HI. This study reveals the importance of the temporal dynamics of water movement in this Aquic Argiudoll, although

  17. Heart rate variables in the Vascular Quality Initiative are not reliable predictors of adverse cardiac outcomes or mortality after major elective vascular surgery

    PubMed Central

    Scali, Salvatore; Bertges, Daniel; Neal, Daniel; Patel, Virendra; Eldrup-Jorgensen, Jens; Cronenwett, Jack; Beck, Adam

    2015-01-01

    associations disappeared in controlling for beta-blocker status. For AFB and open AAA repair patients, there was no significant association between AHR and MACE or 30-day mortality, irrespective or cardiac risk or beta-blocker status. DHR and extremes of highest intraoperative HR (>90 or 100 beats/min) were analyzed among all three operations, and no consistent associations with MACE or 30-day mortality were detected. Conclusions The VQI AHR and highest intraoperative HR variables are highly confounded by patient presentation, operative variables, and beta-blocker therapy. The discordance between cardiac risk and HR as well as the lack of consistent correlation to outcome makes them unreliable predictors. The VQI has elected to discontinue collecting AHR and highest intraoperative HR data, given insufficient evidence to suggest their importance as an outcome measure. PMID:26067200

  18. 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

    2015-08-01

    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

  19. Physical properties and the variability mechanism of the He I outflow in NGC 4151

    NASA Astrophysics Data System (ADS)

    Wildy, C.; Landt, H.; Goad, M. R.; Ward, M.; Collinson, J. S.

    2016-09-01

    We report on variable helium absorption lines in NGC 4151 observed across six epochs of quasi-simultaneous near-infrared and optical data. These observations cover the transitions from the metastable 23S state at 3889 Å and 10 830 Å, and from the 21S state at 20 587 Å. This is the first active galactic nuclei absorption line variability study to include measurements of the 20 587 Å line. The physical properties of the absorber recorded at the fifth observational epoch are relatively well constrained by the presence of absorption in both the optical and near-infrared components, with the 10 830 Å line likely saturated. The observations suggest variations in this absorber's strength are best explained by ionization changes in response to a variable incident continuum. Photoionization simulations constrain the total hydrogen number density of the epoch 5 absorber to 7.1 ≤ log(nH/cm-3) ≤ 8.8, the hydrogen column density to 21.2 ≤ log(NH/cm-2) ≤ 23.3 and the ionization parameter range to -1.9 ≤ logU ≤ 0.4. The simulations also suggest the absorber is located between 0.03 and 0.49 pc from the continuum emission region. This range in physical properties is consistent with an absorber of similar velocity seen in NGC 4151 from previous ultraviolet and optical studies, but with high column density X-ray absorbing components not present. The mass outflow rate due to the fifth epoch absorber is in the range 0.008 to 0.38 M⊙ yr-1, too low to contribute to galaxy feedback effects.

  20. 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

  1. Moderate-to-Vigorous Physical Activity and Sedentary Behavior: Independent Associations With Body Composition Variables in Brazilian Children.

    PubMed

    Ferrari, Gerson Luis de Moraes; Oliveira, Luis Carlos; Araujo, Timoteo Leandro; Matsudo, Victor; Barreira, Tiago V; Tudor-Locke, Catrine; Katzmarzyk, Peter

    2015-08-01

    This study aimed to analyze the independent associations of accelerometer-determined sedentary behavior, physical activity, and steps/day with body composition variables in Brazilian children. 485 children wore accelerometers for 7 days. Variables included time in sedentary behavior and different physical activity intensities (light, moderate, vigorous, or moderate-to-vigorous) and steps/day. Body fat percentage was measured using a bioelectrical impedance scale, and BMI was calculated. Children spent 55.7% of the awake portion of the day in sedentary behavior, 37.6% in light physical activity, 4.6% in moderate physical activity, and 1.9% in vigorous physical activity. Moderate-to-vigorous physical activity and steps/day were negatively associated with body composition (BMI and body fat percentage) variables, independent of sex and sedentary behavior. Beta values were higher for vigorous physical activity than moderate physical activity. Vigorous physical activity was negatively associated with BMI (β-.1425) and body fat percentage (β-.3082; p < .0001). In boys, there were significant negative associations between moderate, vigorous, and moderate-to-vigorous physical activity and steps/day with body composition, and in girls, there was only a negative association with vigorous physical activity, independent of sedentary behavior. Moderate-to-vigorous physical activity and steps/day (in boys), but especially vigorous physical activity (in boys and girls), are associated with body composition, independent of sedentary behavior. Sedentary behavior was not related with any of the body composition variables once adjusted for moderate-to-vigorous physical activity. PMID:25902556

  2. Qualitative and Quantitative Variables in a Selective Admissions Process.

    ERIC Educational Resources Information Center

    Gramet, Pamela; Terragina, Lorraine

    1988-01-01

    A retrospective study of the quantitative and qualitative variables that were the best predictors of successful completion of a bachelor's degree in physical therapy supports continued use of qualitative measures such as interviews and does not support certain traditional quantitative variables. (MSE)

  3. Assessing Morphological Awareness as a Predictor of Academic Performance and Performance on the National Physical Therapy Examination

    ERIC Educational Resources Information Center

    Moran, Kelley A.

    2012-01-01

    The primary purpose of this study was to validate a method for assessing Morphological Awareness (MA) using multimorphemic words commonly used in the academic and clinical practice settings of physical therapy. The Medical Morphology Test (MMT) was developed for this study and was compared to scores on the Nelson-Denny Reading Test (NDRT©). The…

  4. Predictors of Learned Helplessness among Average and Mildly Gifted Girls and Boys Attending Initial High School Physics Instruction in Germany

    ERIC Educational Resources Information Center

    Ziegler, Albert; Finsterwald, Monika; Grassinger, Robert

    2005-01-01

    In mathematics, physics, and chemistry, women are still considered to be at a disadvantage. In the present study, the development of the symptoms of learned helplessness was of particular interest. A study involving average and mildly gifted 8th-grade boys and girls (top 60%) investigated whether girls, regardless of ability level, experience…

  5. Social and Physical Aggression Trajectories from Childhood through Late Adolescence: Predictors of Psychosocial Maladjustment at Age 18

    ERIC Educational Resources Information Center

    Ehrenreich, Samuel E.; Beron, Kurt J.; Underwood, Marion K.

    2016-01-01

    This research examined whether following social and physical aggression trajectories across Grades 3-12 predicted psychological maladjustment. Teachers rated participants' (n = 287, 138 boys) aggressive behavior at the end of each school year. Following the 12th grade, psychosocial outcomes were measured: rule-breaking behaviors, internalizing…

  6. Childhood and Adolescent Sports Participation as Predictors of Participation in Sports and Physical Fitness Activities during Young Adulthood

    ERIC Educational Resources Information Center

    Perkins, Daniel F.; Jacobs, Janis E.; Barber, Bonnie L.; Eccles, Jacquelynne S.

    2004-01-01

    This study examined whether organized sports participation during childhood and adolescence was related to participation in sports and physical fitness activities in young adulthood. The data were from the Michigan Study of Adolescent Life Transitions. The analyses include more than 600 respondents from three waves of data (age 12, age 17, and age…

  7. Predictors and grade level trends of school day physical activity achievement in low-income children from the U.S.

    PubMed

    Burns, Ryan D; Brusseau, Timothy A; Fang, Yi; Myrer, Rachel S; Fu, You; Hannon, James C

    2015-01-01

    The achievement of recommended levels (≥ 30 min/day) of school moderate-to-vigorous physical activity (MVPA) is paramount to decrease risk of chronic disease in children from low-income families. The purpose of this study was to examine the predictors and grade-level trends of school day MVPA achievement in low-income children. Data were collected during the Fall of 2014 on 1232 children (Mean age = 8.8 ± 1.6 years; 625 girls, 607 boys) recruited from three low-income schools from the state of Utah in the U.S. Children wore pedometers for one school week and a stratified random subsample (n = 533) also wore accelerometers to record sedentary time and MVPA. Generalized linear mixed models were employed to calculate odds ratios for achieving school MVPA standards (≥ 30 min/day) from various predictors and to determine odds of achievement across grade levels, accounting for school and classroom clustering. Odds of meeting MVPA standards were 3 times greater if a student achieved at least 6000 steps during the school day (p < 0.01), and were 55% lower for every 1% increase in sedentary time (p < 0.001). Older children had 26% lower odds of meeting the recommended levels of MVPA compared to children in an immediately younger grade level (p < 0.05). A significant proportion of MVPA variance was explained by classroom and school affiliation (Rho = 0.09 to 0.54, p < 0.001). Daily steps, sedentary times, grade level, and classroom and school affiliation associate with school MVPA achievement in low-income children. PMID:26844162

  8. Spatial Variability Some Physical and Chemical Prpperties Soil surface In Dasht-e-Tabriz Different Landforms

    NASA Astrophysics Data System (ADS)

    Foroughifar, Hamed; Asghar Jafarzadeh, Ali; Torabi, Hosien; Aliasgharzad, Naser; Toomanian, Norair

    2010-05-01

    Spatial distribution of soil properties at the field and watershed scale(region scale) affect yield potential, hydrologic responses , and transport of herbicides and No3 to surface or groundwater.The present study aim was to evaluate some physical and chemical properties spatial variability and frequency distribution within and between landforms of Dash-e-Tabriz in the northwest of Iran.For this evaluation 98 samples from soils surface of layer according to grid sampling design and with 500-1000 meters distance based on soils variability were selected and analysed.Landforms were hill, piedmont plain, plain, river alluvial plain and lowland.The study of soil variables frequency distribution showed that Bd, CEC, Caco3, pH,clay and silt follow normal distribution ,which to study their variation one can use parametric statistical method.Variables such as MWD, N(total), SAR, EC, P(available) and sand showed log-normal distribution,that for their variation study,should first be transformed to a logarithmic scale.The variables frequency distribution increase within landforms,which in lowland, hill, and river alluvial plain they showed normal distribution and only EC in piedmont plain and sand, OC and N(total) in plain had log-normal distributions.The results indicate significantly differences of soil properties distribution among landforms,which clay ,pH, EC ,SAR and MWD, CEC, Bd, N(total), OC, P(available), sand, silt were strongly and moderately spatial dependent respectively and Caco3 had no spatial dependence and it is following nugget model.These results indicate that strong spatial dependence due to the effects of intrinsic factors such as parent material, relief and soil types. Also soil properties variations result from variation in depositional environments and or differences in pedogenic or hydrologic processes for different landform positions,and so it can be affected by the flood irrigation,fertilizeir addition,high watertable level or agriculture practices

  9. Socioeconomic and physical distance to the maternity hospital as predictors for place of delivery: an observation study from Nepal

    PubMed Central

    Wagle, Rajendra Raj; Sabroe, Svend; Nielsen, Birgitte Bruun

    2004-01-01

    Background Although the debate on the safety and women's right of choice to a home delivery vs. hospital delivery continues in the developed countries, an undesirable outcome of home delivery, such as high maternal and perinatal mortality, is documented in developing countries. The objective was to study whether socio-economic factors, distance to maternity hospital, ethnicity, type and size of family, obstetric history and antenatal care received in present pregnancy affected the choice between home and hospital delivery in a developing country. Methods This cross-sectional study was done during June, 2001 to January 2002 in an administratively and geographically well-defined territory with a population of 88,547, stretching from urban to adjacent rural part of Kathmandu and Dhading Districts of Nepal with maximum of 5 hrs of distance from Maternity hospital. There were no intermediate level of private or government hospital or maternity homes in the study area. Interviews were carried out on 308 women who delivered within 45 days of the date of the interview with a pre-tested structured questionnaire. Results A distance of more than one hour to the maternity hospital (OR = 7.9), low amenity score status (OR = 4.4), low education (OR = 2.9), multi-parity (OR = 2.4), and not seeking antenatal care in the present pregnancy (OR = 4.6) were statistically significantly associated with an increased risk of home delivery. Ethnicity, obstetric history, age of mother, ritual observance of menarche, type and size of family and who is head of household were not statistically significantly associated with the place of delivery. Conclusions The socio-economic standing of the household was a stronger predictor of place of delivery compared to ethnicity, the internal family structure such as type and size of family, head of household, or observation of ritual days by the mother of an important event like menarche. The results suggested that mothers, who were in the low

  10. Heteroscedasticity generated by errors in predictors

    SciTech Connect

    Downing, D.J.; Fedorov, V.V.; Nanstad, R.K.

    1995-11-01

    The heteroscedasticity or changing variance observed ``raw`` data may be the result of randomness or uncertainty in the predictor variables. As an example we consider ``Charpy Test`` experiments widely used to characterize the ductile-brittle toughness of steels such as those used for nuclear pressure vessels. While this type of experiment is of interest in itself, our main objective is to show that the use of a proper statistical technique may help to avoid the use of more complicated physical models to explain the heteroscedasticity of the observations. We also extend the existing method of regression analysis with errors in controllable variables to the case when the variances of the response and the controllable variables are both unknown.

  11. Self-Reported Sleep Duration and Time in Bed as Predictors of Physical Function Decline: Results from the InCHIANTI Study

    PubMed Central

    Stenholm, Sari; Kronholm, Erkki; Bandinelli, Stefania; Guralnik, Jack M.; Ferrucci, Luigi

    2011-01-01

    Study Objectives: To characterize elderly persons into sleep/rest groups based on their self-reported habitual total sleeping time (TST) and habitual time in bed (TIB) and to examine the prospective association between sleep/rest behavior on physical function decline. Design: Population-based InCHIANTI study with 6 years follow-up (Tuscany, Italy). Setting: Community. Participants: Men and women aged ≥ 65 years (n = 751). Measurements and Results: At baseline, participants were categorized into 5 sleep/rest behavior groups according to their self-reported TST and TIB, computed from bedtime and wake-up time. Physical function was assessed at baseline and at 3- and 6-year follow-ups as walking speed, the Short Physical Performance Battery (SPPB), and self-reported mobility disability (ability to walk 400 m or climb one flight of stairs). Both long (≥ 9 h) TST and long TIB predicted accelerated decline in objectively measured physical performance and greater incidence in subjectively assessed mobility disability, but short (≤ 6 h) TST did not. After combining TST and TIB, long sleepers (TST and TIB ≥ 9 h) experienced the greatest decline in physical performance and had the highest risk for incident mobility disability in comparison to mid-range sleepers with 7-8 h TST and TIB. Subjective short sleepers reporting short (≤ 6 h) TST but long (≥ 9 h) TIB showed a greater decline in SPPB score and had a higher risk of incident mobility disability than true short sleepers with short (≤ 6 h) TST and TIB ≤ 8 hours. Conclusions: Extended time in bed as well as long total sleeping time is associated with greater physical function decline than mid-range or short sleep. TIB offers important additive information to the self-reported sleep duration when evaluating the consequences of sleep duration on health and functional status. Citation: Stenholm S; Kronholm K; Bandinelli S; Guralnik JM; Ferrucci. Self-reported sleep duration and time in bed as predictors of

  12. Persisting Effects of Concussion on Heart Rate Variability during Physical Exertion.

    PubMed

    Abaji, Joseph Patrick; Curnier, Daniel; Moore, Robert Davis; Ellemberg, Dave

    2016-05-01

    The purpose of this study was to evaluate cardiac autonomic modulation in university athletes during the post-acute to late phase (mean, 95 days ±63) of injury at rest and during physical exertion. We also sought to evaluate the effect of time since injury and number of injuries on heart rate variability (HRV). We hypothesized that physical exertion would reveal persisting modifications in HRV following a concussion. We included, in a cross-sectional design, athletes who sustained a concussion and matched controls. Concussions were identified by a medical doctor using established criteria. Twelve male concussed and 12 control athletes took part in the study. Control participants were teammates who were chosen to match the concussed athletes with regard to their height, weight, education, and age. The beat-to-beat electrocardiogram intervals of the participants were measured at rest and during physical exertion (isometric hand grip contraction; IHGC), which was sustained for 3 minutes at 30% of the participants' maximum. Linear and nonlinear parameters of HRV were calculated. The ratio between low and high frequency (LF/HF) bands was calculated to assess the sympathovagal balance. During the IHGC, but not at rest, concussed athletes presented significantly lower power in HF bands, leading to a significantly higher LF/HF ratio (p ≤ 0.05). Thus, asymptomatic athletes still may exhibit modifications in cardiac autonomic modulation weeks to months following injury. These modifications may only become apparent during physical exertion. Monitoring HRV may aid diagnosis and provide insight about safe return to play. PMID:26159461

  13. The role of physical activity and heart rate variability for the control of work related stress

    PubMed Central

    Tonello, Laís; Rodrigues, Fábio B.; Souza, Jeniffer W. S.; Campbell, Carmen S. G.; Leicht, Anthony S.; Boullosa, Daniel A.

    2014-01-01

    Physical activity (PA) and exercise are often used as tools to reduce stress and therefore the risk for developing cardiovascular diseases (CVD). Meanwhile, heart rate variability (HRV) has been utilized to assess both stress and PA or exercise influences. The objective of the present review was to examine the current literature in regards to workplace stress, PA/exercise and HRV to encourage further studies. We considered original articles from known databases (PubMed, ISI Web of Knowledge) over the last 10 years that examined these important factors. A total of seven studies were identified with workplace stress strongly associated with reduced HRV in workers. Longitudinal workplace PA interventions may provide a means to improve worker stress levels and potentially cardiovascular risk with mechanisms still to be clarified. Future studies are recommended to identify the impact of PA, exercise, and fitness on stress levels and HRV in workers and their subsequent influence on cardiovascular health. PMID:24600407

  14. Conceptualising computerized adaptive testing for measurement of latent variables associated with physical objects

    NASA Astrophysics Data System (ADS)

    Camargo, F. R.; Henson, B.

    2015-02-01

    The notion of that more or less of a physical feature affects in different degrees the users' impression with regard to an underlying attribute of a product has frequently been applied in affective engineering. However, those attributes exist only as a premise that cannot directly be measured and, therefore, inferences based on their assessment are error-prone. To establish and improve measurement of latent attributes it is presented in this paper the concept of a stochastic framework using the Rasch model for a wide range of independent variables referred to as an item bank. Based on an item bank, computerized adaptive testing (CAT) can be developed. A CAT system can converge into a sequence of items bracketing to convey information at a user's particular endorsement level. It is through item banking and CAT that the financial benefits of using the Rasch model in affective engineering can be realised.

  15. Personal Meaning, Optimism, and Choice: Existential Predictors of Depression in Community and Institutional Elderly.

    ERIC Educational Resources Information Center

    Reker, Gary T.

    1997-01-01

    Examines the unique, combined, and interactive contribution of existential variables and traditional measures as predictors of depression in institutionalized and community-residing older adults. Results show that choice-responsibleness, social resources, and physical health predicted depression in community elderly; personal meaning, optimism,…

  16. Individual variability in the core interthreshold zone as related to body physique, somatotype, and physical constitution.

    PubMed

    Kakitsuba, Naoshi; Mekjavic, Igor B; Katsuura, Tetsuo

    2009-11-01

    For evaluating the effect of body physique, somatotype, and physical constitution on individual variability in the core interthreshold zone (CIZ), data from 22 healthy young Japanese male subjects were examined. The experiment was carried out in a climatic chamber in which air temperature was maintained at 20-24 degrees C. The subjects' body physique and the maximum work load were measured. Somatotype was predicted from the Heath-Carter Somatotype method. In addition, factors reflecting physical constitution, for example, susceptibility to heat and cold, and quality of sleep were obtained by questionnaire. The subjects wore a water-perfused suit which was perfused with water at a temperature of 25 degrees C and at a rate of 600 cc/min, and exercised on an ergometer at 50% of their maximum work rate for 10-15 min until their sweating rate increased. They then remained continuously seated without exercise until shivering increased. Rectal temperature (T(re)) and skin temperatures at four sites were monitored by thermistors, and sweating rate was measured at the forehead with a sweat rate monitor. Oxygen uptake was monitored with a gas analyzer. The results showed individual variability in the CIZ. According to the reciprocal cross-inhibition (RCI) theory, thermoafferent information from peripheral and core sensors is activated by T(re), mean skin temperature (T(sk)), and their changes. Since T(sk) was relatively unchanged, the data were selected to eliminate the influence of the core cooling rate on the sensor-to-effector pathway before RCI, and the relationship between the CIZ and the various factors was then analyzed. The results revealed that susceptibility to heat showed a good correlation with the CIZ, indicating that individual awareness of heat may change the CIZ due to thermoregulatory behavior. PMID:20009375

  17. Leisure-Time Physical Activity, Sedentary Behavior, and Physical Fitness among Adolescents: Varying Definitions Yield Differing Results in Fitness Research

    ERIC Educational Resources Information Center

    Kerner, Matthew S.

    2005-01-01

    The aims of the study were (1) to assess the relationships among leisure-time physical activity, sedentary behaviors, and measures of health-related and performance-related physical fitness, and (2) to determine the primary predictors of performance-related physical fitness from the variables investigated. This study updates the literature with…

  18. Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial.

    PubMed

    van der Zwan, Judith Esi; de Vente, Wieke; Huizink, Anja C; Bögels, Susan M; de Bruin, Esther I

    2015-12-01

    In contemporary western societies stress is highly prevalent, therefore the need for stress-reducing methods is great. This randomized controlled trial compared the efficacy of self-help physical activity (PA), mindfulness meditation (MM), and heart rate variability biofeedback (HRV-BF) in reducing stress and its related symptoms. We randomly allocated 126 participants to PA, MM, or HRV-BF upon enrollment, of whom 76 agreed to participate. The interventions consisted of psycho-education and an introduction to the specific intervention techniques and 5 weeks of daily exercises at home. The PA exercises consisted of a vigorous-intensity activity of free choice. The MM exercises consisted of guided mindfulness meditation. The HRV-BF exercises consisted of slow breathing with a heart rate variability biofeedback device. Participants received daily reminders for their exercises and were contacted weekly to monitor their progress. They completed questionnaires prior to, directly after, and 6 weeks after the intervention. Results indicated an overall beneficial effect consisting of reduced stress, anxiety and depressive symptoms, and improved psychological well-being and sleep quality. No significant between-intervention effect was found, suggesting that PA, MM, and HRV-BF are equally effective in reducing stress and its related symptoms. These self-help interventions provide easily accessible help for people with stress complaints. PMID:26111942

  19. A standardized approach to study human variability in isometric thermogenesis during low-intensity physical activity

    PubMed Central

    Sarafian, Delphine; Miles-Chan, Jennifer L.; Yepuri, Gayathri; Montani, Jean-Pierre; Schutz, Yves; Dulloo, Abdul G.

    2013-01-01

    Limitations of current methods: The assessment of human variability in various compartments of daily energy expenditure (EE) under standardized conditions is well defined at rest [as basal metabolic rate (BMR) and thermic effect of feeding (TEF)], and currently under validation for assessing the energy cost of low-intensity dynamic work. However, because physical activities of daily life consist of a combination of both dynamic and isometric work, there is also a need to develop standardized tests for assessing human variability in the energy cost of low-intensity isometric work. Experimental objectives: Development of an approach to study human variability in isometric thermogenesis by incorporating a protocol of intermittent leg press exercise of varying low-intensity isometric loads with measurements of EE by indirect calorimetry. Results: EE was measured in the seated position with the subject at rest or while intermittently pressing both legs against a press-platform at 5 low-intensity isometric loads (+5, +10, +15, +20, and +25 kg force), each consisting of a succession of 8 cycles of press (30 s) and rest (30 s). EE, integrated over each 8-min period of the intermittent leg press exercise, was found to increase linearly across the 5 isometric loads with a correlation coefficient (r) > 0.9 for each individual. The slope of this EE-Load relationship, which provides the energy cost of this standardized isometric exercise expressed per kg force applied intermittently (30 s in every min), was found to show good repeatability when assessed in subjects who repeated the same experimental protocol on 3 separate days: its low intra-individual coefficient of variation (CV) of ~ 10% contrasted with its much higher inter-individual CV of 35%; the latter being mass-independent but partly explained by height. Conclusion: This standardized approach to study isometric thermogenesis opens up a new avenue for research in EE phenotyping and metabolic predisposition to obesity

  20. Predictors of physical activity, healthy eating and being smoke-free in teens: a theory of planned behaviour approach.

    PubMed

    Murnaghan, Donna A; Blanchard, Chris M; Rodgers, Wendy M; LaRosa, Jennifer N; MacQuarrie, Colleen R; MacLellan, Debbie L; Gray, Bob J

    2010-10-01

    This paper elicited context specific underlying beliefs for physical activity, fruit and vegetable consumption and smoke-free behaviour from the Theory of Planned Behaviour (TPB), and then determined whether the TPB explained significant variation in intentions and behaviour over a 1 month period in a sample of grade 7-9 (age 12-16 years) adolescents. Eighteen individual interviews and one focus group were used to elicit student beliefs. Analyses of this data produced behavioural, normative and control beliefs which were put into a TPB questionnaire completed by 183 students at time 1 and time 2. The Path analyses from the main study showed that the attitude/intention relationship was moderately large for fruit and vegetable consumption and small to moderate for being smoke free. Perceived behavioural control had a large effect on being smoke free and a moderately large effect for fruit and vegetable consumption and physical activity. Intention had a large direct effect on all three behaviours. Common (e.g. feel better, more energy) and behaviour-specific (e.g., prevent yellow fingers, control my weight) beliefs emerged across the three health behaviours. These novel findings, to the adolescent population, support the importance of specific attention being given to each of the behaviours in future multi-behavioural interventions. PMID:20204952

  1. Changes in the Hurst Exponent of Heart Rate Variability during Physical Activity

    NASA Astrophysics Data System (ADS)

    Aoyagi, Naoko; Kiyono, Ken; Struzik, Zbigniew R.; Yamamoto, Yoshiharu

    2005-08-01

    We examine fractal scaling properties of heart rate variability using detrended fluctuation analysis (DFA), during physical activity in healthy subjects. We analyze 11 records of healthy subjects, which include both usual daily activity and experimental exercise. The subjects were asked to ride on a bicycle ergometer for 2.5 hours, and maintained a heartbeat interval of 500-600 ms. In order to estimate the long-range correlation in the series of heartbeat intervals during controlled physical activity, we apply DFA to the data set with the third-order polynomial trend removed. For all records during exercise, we observe a characteristic crossover phenomenon at ≈ 300 beats. The scaling exponent in the range > 300 beats (> 3 minutes) during exercise decreases and tends to be closer to white noise (≈ 0.5), which corresponds to uncorrelated behavior. The long-range scaling exponent during exercise is significantly lower than that during daily activity in this range. Contrary to the currently held view, our results indicate a breakdown in long-range correlations and 1/f-like scaling, rather than the increase in the Hurst exponent characteristic of a (congestive) increase in afterload and observed, e.g., in congestive heart failure (CHF) patients. Further, our results suggest an increased load imbalance induced departure from critical-like behavior, which has recently been reported in healthy human heart rate during daily activity.

  2. Effects of Endolithic Parasitism on Invasive and Indigenous Mussels in a Variable Physical Environment

    PubMed Central

    McQuaid, Christopher David; Gektidis, Marcos

    2009-01-01

    Biotic stress may operate in concert with physical environmental conditions to limit or facilitate invasion processes while altering competitive interactions between invaders and native species. Here, we examine how endolithic parasitism of an invasive and an indigenous mussel species acts in synergy with abiotic conditions of the habitat. Our results show that the invasive Mytilus galloprovincialis is more infested than the native Perna perna and this difference is probably due to the greater thickness of the protective outer-layer of the shell of the indigenous species. Higher abrasion due to waves on the open coast could account for dissimilarities in degree of infestation between bays and the more wave-exposed open coast. Also micro-scale variations of light affected the level of endolithic parasitism, which was more intense at non-shaded sites. The higher levels of endolithic parasitism in Mytilus mirrored greater mortality rates attributed to parasitism in this species. Condition index, attachment strength and shell strength of both species were negatively affected by the parasites suggesting an energy trade-off between the need to repair the damaged shell and the other physiological parameters. We suggest that, because it has a lower attachment strength and a thinner shell, the invasiveness of M. galloprovincialis will be limited at sun and wave exposed locations where endolithic activity, shell scouring and risk of dislodgement are high. These results underline the crucial role of physical environment in regulating biotic stress, and how these physical-biological interactions may explain site-to-site variability of competitive balances between invasive and indigenous species. PMID:19668334

  3. Heart Rate Variability in Adolescents – Normative Data Stratified by Sex and Physical Activity

    PubMed Central

    Sharma, Vivek Kumar; Arunachalam, Vinayathan; Rajendran, Rajathi

    2015-01-01

    Background Heart rate variability (HRV) refers to the beat-to-beat fluctuations in the cardiac rhythm occurring due to modulation of the pacemaker (sinoatrial node) activity of the heart by the sympathetic and parasympathetic branches of the autonomic nervous system. Nowadays, cardiovascular diseases and their risk factors are increasingly occurring at a younger age (children and adolescents) and recording of HRV in them will help us to identify cardiovascular autonomic derangement earlier. However, to be used clinically, normative data has to be established in this age group considering other major factors that can influence HRV such as sex, physical activity, and BMI. Materials and Methods Task Force of the European Society of Cardiology and the North American Society of Pacing and Electrophysiology has provided the standards for measurement of heart rate variability and we have followed the same. In the present study, we have described the normative data for HRV in the adolescent in the age group of 12-17 years, stratified based on sex and physical activity. Results Data given below are expressed as median with interquartile range (Median (IQR)) in the following order: non-athlete girls, non athlete boys, athlete girls and athlete boys. Time domain indices - SDNN - 66.35 (40.78), 63.20 (36.20), 113.00 (31.40) and 94.20 (35.55); RMSSD – 69.00 (50.55), 58.70 (43.40), 94.90 (42.10) and 100.30 (47.50); NN50 - 137.50 (100.25), 116.00 (90.50), 137.00 (81.00) and 156.00 (81.50). The frequency domain indices – LF power 1015.00 (1098.75), 945.00 (831.00), 1465 (642.25), and 1211.00 (811.37); HF power – 1324.00 (1707.00), 988.00 (1426.50), 2409.00 (1387.50), and 2219.00 (1752.00); Total power – 3374.50 (3094.25), 2757.00 (2641.00), 5202.00 (2501.50) and 5273.00 (3507.50); LFnu – 45.44 (16.61), 47.63 (29.98), 38.59 (11.81) and 37.10 (11.21); HFnu – 54.56 (16.61), 52.37 (29.98), 61.41 (11.81) and 62.90 (11.21). Conclusion We have given sex and physical activity

  4. Family-Based Predictors of Adolescent Substance Use.

    ERIC Educational Resources Information Center

    Vakalahi, Halaevalu F.

    2002-01-01

    Examines family-based variables as predictors of adolescent substance use. Overall, this study supported prior research, indicating certain family variables as predictors of adolescent substance use. Sibling marijuana use, family involvement, and religious affiliation were predictors of adolescent tobacco use. Family involvement, sibling tobacco…

  5. A new variable-resolution associative memory for high energy physics

    SciTech Connect

    Annovi, A.; Amerio, S.; Beretta, M.; Bossini, E.; Crescioli, F.; Dell'Orso, M.; Giannetti, P.; Hoff, J.; Liu, T.; Magalotti, D.; Piendibene, M.; Sacco, I.; Schoening, A.; Soltveit, H. K.; Stabile, A.; Tripiccione, R.; Liberali, V.; Vitillo, R.; Volpi, G.

    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, 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

  6. Changes in and predictors of pain characteristics in patients with head and neck cancer undergoing radiotherapy.

    PubMed

    Astrup, Guro Lindviksmoen; Rustøen, Tone; Miaskowski, Christine; Paul, Steven M; Bjordal, Kristin

    2015-05-01

    Pain is a common symptom in patients with head and neck cancer (HNC) that is associated with significant decrements in physical and psychological functioning. Only 4 studies have evaluated for changes in and predictors of different pain characteristics in these patients. In this longitudinal study of patients with HNC, changes in pain intensity (i.e., average pain, worst pain), pain interference with function, and pain relief were evaluated from the initiation of radiotherapy and through the following 6 months. Hierarchical linear modeling was used to evaluate for changes over time in these 4 pain characteristics, as well as to identify predictors of interindividual variability in each characteristic. Overall, pain intensity and interference with function scores were in the mild-to-moderate range, while pain relief scores were in the moderate range. The occurrence of pain, as well as scores for each pain characteristic, increased from the initiation to the completion of radiotherapy, followed by a gradual decrease to near pretreatment levels at 6 months. However, interindividual variability existed in patients' ratings of each pain characteristic. Predictors of more severe pain characteristic scores were more comorbidities, worse physical functioning, not having surgery before radiotherapy, difficulty swallowing, mouth sores, sleep disturbance, fatigue, more energy, and less social support. Patients with more depressive symptoms had better pain relief. Although some of the predictors cannot be modified (e.g., rrence of surgery), other predictors (e.g., symptoms) can be treated. Therefore, information about these predictors may result in decreased pain in patients with HNC. PMID:25719616

  7. Correlation Study of Physics Achievement, Learning Strategy, Attitude and Gender in an Introductory Physics Course

    ERIC Educational Resources Information Center

    Sezgin Selcuk, Gamze

    2010-01-01

    This study investigates the relationship between multiple predictors of physics achievement including reported use of four learning strategy clusters (elaboration, organization, comprehension monitoring and rehearsal), attitudes towards physics (sense of care and sense of interest) and a demographic variable (gender) in order to determine the…

  8. An examination of variables which influence high school students to enroll in an undergraduate engineering or physical science major

    NASA Astrophysics Data System (ADS)

    Porter, Christopher H.

    The purpose of this study was to examine the variables which influence a high school student to enroll in an engineering discipline versus a physical science discipline. Data was collected utilizing the High School Activities, Characteristics, and Influences Survey, which was administered to students who were freshmen in an engineering or physical science major at an institution in the Southeastern United States. A total of 413 students participated in the survey. Collected data were analyzed using descriptive statistics, two-sample Wilcoxon tests, and binomial logistic regression techniques. A total of 29 variables were deemed significant between the general engineering and physical science students. The 29 significant variables were further analyzed to see which have an independent impact on a student to enroll in an undergraduate engineering program, as opposed to an undergraduate physical science program. Four statistically significant variables were found to have an impact on a student's decision to enroll in a engineering undergraduate program versus a physical science program: father's influence, participation in Project Lead the Way, and the subjects of mathematics and physics. Recommendations for theory, policy, and practice were discussed based on the results of the study. This study presented suggestions for developing ways to attract, educate, and move future engineers into the workforce.

  9. Variability in performance on a work simulation test of physical fitness for firefighters.

    PubMed

    Boyd, Liam; Rogers, Todd; Docherty, David; Petersen, Stewart

    2015-04-01

    The Canadian Forces Firefighter Physical Fitness Maintenance Evaluation (FF PFME) requires firefighters in full fire-protective ensemble, including self-contained breathing apparatus, to correctly complete 10 work-related tasks on a measured and calibrated course. Fitness for duty is inferred from completion time of the course. We hypothesized that completion time may be dependent on pacing strategy and day-to-day fluctuations in biological function. To examine variability in performance, 20 females and 31 males (mean ± SD; age, 27.6 ± 10.5 years; height, 176.7 ± 8.3 cm; mass, 77.3 ± 13.4 kg) were familiarized with the FF PFME and then completed the test on 6 separate days. Pre-test behaviours (e.g., sleep, diet) and test conditions (e.g., calibration, time of day) were consistent. Repeated-measures ANOVA revealed a significant decrease in completion time between tests 1 and 6 (18.7%) and between all sequential pairs (e.g., tests 1 and 2). There was also a small but significant increase in the fraction of total test time for task completion and a corresponding decrease in the time to transition between tasks. The performance improvements cannot be explained by differences in effort (heart rate and perceived exertion). Coefficient of variation for tests 1, 2, and 3 was 7% and for tests 4, 5, and 6 was 2.6%. The results indicate the importance of practice on performance and the potential for false-positive or false-negative decision errors if biological variability is not taken into account. PMID:25781347

  10. Spectral Predictors

    SciTech Connect

    Ibarria, L; Lindstrom, P; Rossignac, J

    2006-11-17

    Many scientific, imaging, and geospatial applications produce large high-precision scalar fields sampled on a regular grid. Lossless compression of such data is commonly done using predictive coding, in which weighted combinations of previously coded samples known to both encoder and decoder are used to predict subsequent nearby samples. In hierarchical, incremental, or selective transmission, the spatial pattern of the known neighbors is often irregular and varies from one sample to the next, which precludes prediction based on a single stencil and fixed set of weights. To handle such situations and make the best use of available neighboring samples, we propose a local spectral predictor that offers optimal prediction by tailoring the weights to each configuration of known nearby samples. These weights may be precomputed and stored in a small lookup table. We show that predictive coding using our spectral predictor improves compression for various sources of high-precision data.

  11. Heart rate variability and depressed mood in physical education students: a longitudinal study.

    PubMed

    Pichon, Aurélien; Nuissier, Frédéric; Chapelot, Didier

    2010-08-25

    Autonomic nervous system (ANS) activity, and more specifically its parasympathetic component, has been reported to be associated with depression. The objective of this longitudinal study was to assess whether changes in heart rate variability (HRV) and in depressive moods were interrelated in healthy young subjects. Thirty students in physical education with a high physical load, were followed over the university year at 3 periods: October (P1), February (P2) and May (P3). Depressive mood was assessed by the score on the Depression subscale of the profile of mood state (POMS) questionnaire. HRV was assessed in supine and during an active orthostatic test with total power (TPms(2)) as the sum of the very low (VLF), low (LF) and high frequency (HF) bands, LF/HF ratio representing sympathetic and HFms(2) parasympathetic modulations. Results showed that changes in Depression scores between P1 and P2 were negatively and positively associated with changes in TPms(2), LFms(2), and HFms(2) in supine position and during orthostatism respectively. Although Anger/Aggressivity, Fatigue, and Vigor scores of the POMS were also correlated with changes in some HRV indices, Depression was the only significant predictive factor of changes in TPms(2) and HFms(2) between P1 and P2 in supine position and during orthostatism. These results were not observed between P2 and P3. In conclusion, in a healthy young sample of population, changes in depressive moods are associated with changes in total rhythmical power of HRV and more specifically its parasympathetic component. PMID:20447874

  12. Predictors of Outcomes in a Performance Ladder Program.

    ERIC Educational Resources Information Center

    Dicks, Robert H.; McHenry, James D.

    1985-01-01

    Investigated variables from initial inmate evaluations at a state penitentiary as predictors of inmate success in behavioral ladder program. Results indicated that academic test variables were best predictors of overall success level, attitudes, and work habits. Personality variables and one interview observation variable were also found to be…

  13. The Infuence of Physical Variables on Whole-Stream Metabolism in an Arctic Tundra River

    NASA Astrophysics Data System (ADS)

    Cappelletti, C. K.; Bowden, W.

    2005-05-01

    We examined the influence of light, temperature, nutrients, and discharge on whole-stream metabolism (WSM) in three experimental reaches of the Kuparuk River, Alaska, using the open-system, single-station method. Ambient PO4 levels in the reference reach were ~0.05μM, while addition of phosphoric acid since 1983 in the fertilized reach and since 2004 in the ultra-fertilized reach increased PO4 levels to ~0.30μM and ~0.90μM, respectively. Among all reaches, gross primary production (GPP) was positively correlated with light, temperature, and PO4 and negatively correlated with discharge. Temperature explained most of the variance in GPP. Among all reaches, community respiration (CR) was weakly correlated with light, temperature, PO4, and discharge. However, CR showed a greater response to temperature in the fertilized reaches. Benthic respiration by mosses in the fertilized reaches responds to temperature while heterotrophic respiration in the hyporheic zone is similar in all reaches and does not respond to temperature due to thermal buffering. Light, temperature, and discharge were moderately intercorrelated. An Information-Theoretic approach using Akaike's Information Criterion (AIC) was used to examine the relative importance of each physical variable on WSM and to develop a photosynthesis model.

  14. Seasonal variability of bio-optical and physical properties in the Sargasso Sea

    NASA Technical Reports Server (NTRS)

    Dickey, T.; Granata, T.; Marra, J.; Langdon, C.; Wiggert, J.; Chai-Jochner, Z.; Hamilton, M.; Vazquez, J.; Stramska, M.; Bidigare, R.

    1993-01-01

    The seasonal variability of bio-optical and physical properties within the upper ocean at a site in the Sargasso Sea has been observed in multivariable moored systems during a 9-month period. In addition, complementary meteorological data, sea surface height and sea surface temperature maps, and expendable bathythermograph and shipboard profile data have been utilized for interpretation. The observations during March are characteristic of late wintertime conditions of a deep isothermal layer, but with intervening periods of warming due to the advection of warm outbreak waters associated with Gulf Stream meanders. The mixed layer depth shoals from greater than 160 m to about 25 m in late March (spring transition). Phytoplankton blooms follow the mixed layer shoaling. A succession of phytoplankton populations occurs during this transitional interval. The mixed layer remains near 25 m for the summer and deepens in mid-September. A relatively intense subsurface maximum in chlorophyll develops at about 75 m following the spring transition. The maximum persists, but weakens in mid-summer.

  15. Childhood and adolescent predictors of leisure time physical activity during the transition from adolescence to adulthood: a population based cohort study

    PubMed Central

    2011-01-01

    Background Few studies have investigated factors that influence physical activity behavior during the transition from adolescence to adulthood. This study explores the associations of sociodemographic, behavioral, sociocultural, attitudinal and physical factors measured in childhood and adolescence with physical activity behavior during the transition from adolescence to adulthood. Methods Childhood and adolescent data (at ages 7-15 years) were collected as part of the 1985 Australian Health and Fitness Survey and subdivided into sociodemographics (socioeconomic status, parental education), behavioral (smoking, alcohol, sports diversity, outside school sports), sociocultural (active father, active mother, any older siblings, any younger siblings, language spoken at home), attitudinal (sports/recreational competency, self-rated health, enjoyment physical education/physical activity, not enjoying school sports) and physical (BMI, time taken to run 1.6 km, long jump) factors. Physical activity between the ages 15 and 29 years was reported retrospectively using the Historical Leisure Activity Questionnaire at follow-up in 2004-2006 by 2,048 participants in the Childhood Determinants of Adult Health Study (CDAH). Australia's physical activity recommendations for children and adults were used to categorize participants as persistently active, variably active or persistently inactive during the transition from adolescence to adulthood. Results For females, perceived sports competency in childhood and adolescence was significantly associated with being persistently active (RR = 1.88, 95% CI = 1.39, 2.55). Smoking (RR = 0.31 CI = 0.12, 0.82) and having younger siblings (RR = 0.69 CI = 0.52, 0.93) were inversely associated with being persistently active after taking physical and attitudinal factors into account. For males, playing sport outside school (RR = 1.47 CI = 1.05, 2.08), having active fathers (RR = 1.25 CI = 1.01, 1.54) and not enjoying school sport (RR = 4.07 CI

  16. 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

  17. 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

  18. Dramatic variability of the carbonate system of the coastal ocean is regulated by physical and biogeochemical processes on multiple timescales

    NASA Astrophysics Data System (ADS)

    Johnson, Z. I.; Hunt, D.

    2013-12-01

    Increased atmospheric carbon dioxide (CO2) from anthropogenic sources is acidifying marine environments with potentially dramatic implications for the physical, chemical and biological functioning of these ecosystems. If current trends continue, mean ocean pH is expected to decrease by ~0.2 units over the next ~50 years. Yet, at the same time there is substantial spatial and temporal variability in pH and other carbon system parameters in the ocean resulting in regions that already exceed long term projected pH changes, suggesting that short-term variability is an important layer of complexity on top of long term acidification. Thus, in order to develop predictions of future climate change impacts including ocean acidification, there is a critical need to characterize the natural range and variability of the marine CO2 system and the mechanisms responsible for this variability. Here we examine pH and dissolved inorganic carbon (DIC) variability at time intervals spanning 1 hour to >1 year in a dynamic coastal marine system to quantify variability of the carbon system at multiple time scales. Daily and seasonal variability of the carbon system is largely driven by temperature, alkalinity and the balance between primary production and respiration, but high frequency variability (hours to days) is further influenced by water mass movement (e.g. tides) and stochastic events (e.g. storms). Both annual variability (~0.3 units) and diurnal variability (~0.1 units) in coastal ocean acidity are similar in magnitude to long term projections associated with increasing atmospheric CO2 and their drivers highlight the importance of characterizing the complete carbonate system (and not just pH). Short term variability of ocean carbon parameters may already exert significant pressure on some coastal marine ecosystems with implications for ecology, biogeochemistry and evolution and this shorter term variability layers additive effects and complexity, including extreme values, on

  19. Cigarette smoking, physical activity, and alcohol consumption as predictors of cancer incidence among women at high risk of breast cancer in the NSABP P-1 Trial

    PubMed Central

    Land, Stephanie R.; Liu, Qing; Wickerham, D. Lawrence; Costantino, Joseph P.; Ganz, Patricia A.

    2014-01-01

    Background NSABP P-1 provides an opportunity to examine the association of behavioral factors with prospectively monitored cancer incidence and interactions with tamoxifen. Methods From 1992–1997, 13,388 women with estimated 5-year breast cancer (BC) risk greater than 1.66% or a history of lobular carcinoma in situ (87% under age 65; 67% post-menopausal) were randomly assigned to tamoxifen versus placebo. Invasive BC, lung (LC), colon (CC), and endometrial cancers (EC) were analyzed with Cox regression. Predictors were baseline cigarette smoking, leisure-time physical activity, alcohol consumption, and established risk factors. Results At median 7 years follow-up, we observed 395, 66, 35, and 74 BC, LC, CC, and EC, respectively. Women who had smoked were at increased risk of BC (P=.007; hazard ratio (HR)=1.3 for 15–35 years smoking, HR=1.6 for ≥35 years), LC (P<.001; HR=3.9 for 15–35 years; HR=18.4 for ≥35 years), and CC (P<.001; HR=5.1 for ≥35 years) versus never-smokers. Low activity predicted increased BC risk only among women assigned to placebo (P=.021 activity main effect, P=.013 activity-treatment interaction; HR=1.4 for placebo group) and EC among all women (P=.026, HR=1.7). Moderate alcohol (>0–1 drink/day) was associated with decreased risk of CC (P=.019; HR=.35) versus no alcohol. There were no other significant associations between these behaviors and cancer risk. Conclusion Among women with elevated risk of BC, smoking has an even greater impact on BC risk than observed in past studies in the general population. Impact Women who smoke or are inactive should be informed of the increased risk of multiple types of cancer. PMID:24569437

  20. Studies conducted as a search for physical mechanisms relating solar variability and the troposphere

    NASA Technical Reports Server (NTRS)

    Wu, S. T. (Editor)

    1981-01-01

    Chains of causative mechanisms that are hypothesized to relate solar variability to the behavior of the Earth's lower atmosphere were assessed. Solar variations believed most likely to constitute the forcing functions in hypothesized solar terrestrial atmosphere chain, changes in the Earth's atmospheric electrical characteristics due to solar variability, and the observed variations in atmospheric behavior that are influenced by solar variability were also examined.

  1. Predicting Responsiveness to Treatment of Children with Autism: A Retrospective Study of the Importance of Physical Dysmorphology

    ERIC Educational Resources Information Center

    Stoelb, M.; Yarnal, R.; Miles, J.; Takahashi, T. N.; Farmer, J. E.; McCathren, R. B.

    2004-01-01

    This retrospective study examined predictors of outcome for children with autism following 6 and 12 months of early intensive behavioral intervention. Potential predictor variables included pretreatment functioning, age at onset of treatment, treatment intensity, family involvement, and physical characteristics (e.g., brain abnormalities,…

  2. An Examination of Variables Which Influence High School Students to Enroll in an Undergraduate Engineering or Physical Science Major

    ERIC Educational Resources Information Center

    Porter, Christopher H.

    2011-01-01

    The purpose of this study was to examine the variables which influence a high school student to enroll in an engineering discipline versus a physical science discipline. Data was collected utilizing the High School Activities, Characteristics, and Influences Survey, which was administered to students who were freshmen in an engineering or physical…

  3. The rates of change of the stochastic trajectories of acceleration variability are a good predictor of normal aging and of the stage of Parkinson's disease

    PubMed Central

    Torres, Elizabeth B.

    2013-01-01

    The accelerometer data from mobile smart phones provide stochastic trajectories that change over time. This rate of change is unique to each person and can be well-characterized by the continuous two-parameter family of Gamma probability distributions. Accordingly, on the Gamma plane each participant can be uniquely localized by the shape and the scale parameters of the Gamma probability distribution. The scatter of such points contains information that can unambiguously separate the normal controls (NC) from those patients with Parkinson's disease (PD) that are at a later stage of the disease. In general normal aging seems conducive of more predictable patterns of variation in the accelerometer data. Yet this trend breaks down in PD where the statistical signatures seem to be a more relevant predictor of the stage of the disease. Those patients at a later stage of the disease have more random and noisier patterns than those in the earlier stages, whose statistics resemble those of the older NC. Overall the peak rates of change of the stochastic trajectories of the accelerometer are a good predictor of the stage of PD and of the age of a “normally” aging individual. PMID:23882193

  4. Patterns of co-variability among California Current chinook salmon, coho salmon, Dungeness crab, and physical oceanographic conditions

    NASA Astrophysics Data System (ADS)

    Botsford, L. W.; Lawrence, C. A.

    One of the primary motivations for the GLOBEC NEP program was the apparent inverse relationship between the increase in salmon populations in the Gulf of Alaska since the mid-1970s and concurrent declines in salmon populations in the California Current. The increase in abundance of some salmon species in the Gulf of Alaska can be plausibly explained based on mechanisms involving changes in physical structure, biological productivity, and salmon survival. To assess concurrent changes in salmon populations in the California Current and their possible physical and biological bases we examined temporal and spatial patterns of co-variability between biological variables and physical descriptors along the coasts of Washington, Oregon and California, from 1950 to 1990. The biological variables were catch records of coho salmon, chinook salmon and an ecologically related species, Dungeness crab. The physical variables were sea surface temperature, sea surface height (SSH) and the upwelling index (UWI). We found that while California Current coho salmon declined uniformly in the mid-1970s, consistent with the proposed inverse relationship, chinook salmon did not. All three species appear to be driven by the dominant mode of co-variability in the three physical variables, an indicator of warm/cool water conditions, but in different ways. In general, warm conditions have a negative effect on salmon at the age of ocean entry and spawning return, and Dungeness crab during the larval stage, while cool conditions have a positive effect. Differences in spatio-temporal variability between the two salmon species suggest they may respond to ocean conditions differently: coho salmon vary synchronously along the coast on annual time scales, while chinook salmon vary on slightly longer time scales in a specific spatial pattern. Dungeness crab vary on 10-year time scales, synchronously along the coast, except for the most southern areas (central California) where populations collapsed in

  5. Physical and biogeochemical spatial scales of variability in the East Australian Current separation zone from shelf glider measurements

    NASA Astrophysics Data System (ADS)

    Schaeffer, A.; Roughan, M.; Jones, E.; White, D.

    2015-12-01

    In contrast to physical processes, biogeochemical processes are inherently patchy in the ocean, which affects both the observational sampling strategy and the representativeness of sparse measurements in data assimilating models. In situ observations from multiple glider deployments are analyzed to characterize spatial scales of variability in both physical and biogeochemical properties, using an empirical statistical model. We find that decorrelation ranges are strongly dependent on the balance between local dynamics and mesoscale forcing. The shortest horizontal (5-10 km) and vertical (45 m) decorrelation ranges are for chlorophyll a fluorescence. Whereas those variables that are a function of regional ocean and atmosphere dynamics (temperature and dissolved oxygen) result in anisotropic patterns with longer ranges along (28-37 km) than across the shelf (8-19 km). Variables affected by coastal processes (salinity and colored dissolved organic matter) have an isotropic range similar to the baroclinic Rossby radius (10-15 km).

  6. Physical and biogeochemical spatial scales of variability in the East Australian Current separation from shelf glider measurements

    NASA Astrophysics Data System (ADS)

    Schaeffer, Amandine; Roughan, Moninya; Jones, Emlyn M.; White, Dana

    2016-03-01

    In contrast to physical processes, biogeochemical processes are inherently patchy in the ocean, which affects both the observational sampling strategy and the representativeness of sparse measurements in data assimilating models. In situ observations from multiple glider deployments are analysed to characterize spatial scales of variability in both physical and biogeochemical properties, using an empirical statistical model. We find that decorrelation ranges are strongly dependent on the balance between local dynamics and mesoscale forcing. The shortest horizontal (5-10 km) and vertical (45 m) decorrelation ranges are for chlorophyll a fluorescence, whereas those variables that are a function of regional ocean and atmosphere dynamics (temperature and dissolved oxygen) result in anisotropic patterns with longer ranges along (28-37 km) than across the shelf (8-19 km). Variables affected by coastal processes (salinity and coloured dissolved organic matter) have an isotropic range similar to the baroclinic Rossby radius (10-15 km).

  7. First-Order Model Management With Variable-Fidelity Physics Applied to Multi-Element Airfoil Optimization

    NASA Technical Reports Server (NTRS)

    Alexandrov, N. M.; Nielsen, E. J.; Lewis, R. M.; Anderson, W. K.

    2000-01-01

    First-order approximation and model management is a methodology for a systematic use of variable-fidelity models or approximations in optimization. The intent of model management is to attain convergence to high-fidelity solutions with minimal expense in high-fidelity computations. The savings in terms of computationally intensive evaluations depends on the ability of the available lower-fidelity model or a suite of models to predict the improvement trends for the high-fidelity problem, Variable-fidelity models can be represented by data-fitting approximations, variable-resolution models. variable-convergence models. or variable physical fidelity models. The present work considers the use of variable-fidelity physics models. We demonstrate the performance of model management on an aerodynamic optimization of a multi-element airfoil designed to operate in the transonic regime. Reynolds-averaged Navier-Stokes equations represent the high-fidelity model, while the Euler equations represent the low-fidelity model. An unstructured mesh-based analysis code FUN2D evaluates functions and sensitivity derivatives for both models. Model management for the present demonstration problem yields fivefold savings in terms of high-fidelity evaluations compared to optimization done with high-fidelity computations alone.

  8. Characterizing the physical and demographic variables associated with heavy metal distribution along urban-rural gradient.

    PubMed

    Fang, Shubo; Qiao, Yajun; Yin, Chunsheng; Yang, Xiaoying; Li, Ning

    2015-09-01

    This paper describes a study of how the demographic and physical variables affected the heavy metal (HM) contamination along the urban-rural gradient in PuDong New District, Shanghai. The road density (RDi) and the percentage of built-up areas (BAi) were calculated for various widths of buffers around the soil sampling sites. Through distance allocation, the demographic values of the population change index (PCI) were assigned, with the value being associated with the nearest town. We initiated the use of the population migration rate from 2000 to 2010, i.e., PCI, to represent the urbanization rate. Regression analysis between the soil HM concentrations and the PCI, the RD, and the BA was estimated. The results indicated that the PCI significantly affected the Cd and Cu distribution (p < 0.05), while the RD of the 3-km buffer affected the Pb concentrations. The BA of 2-km buffers affected the spatial distribution of Cd, Cu, and Zn. Zn was also affected by the RD within the 4-km buffer. Using the median values of the PCI and the BA of the 2-km buffer, and the RD of the 3-km buffer, logistic analysis was performed to identify the priority areas for managing HM hazards. The two identified priority areas were the towns of Kangqiao and Zhuqiao, both of which were rapidly urbanized areas with higher PCI values. Our research demonstrated that understanding the rate of urbanization may be as important as the degree of urbanization when examining associated HM contamination patterns. PMID:26269103

  9. Temporal variability of selected chemical and physical properties of topsoil of three soil types

    NASA Astrophysics Data System (ADS)

    Jirku, Veronika; Kodesova, Radka; Nikodem, Antonin; Muhlhanselova, Marcela; Zigova, Anna

    2013-04-01

    Temporal variability of soil properties measured in surface horizons of three soil types (Haplic Cambisol, Greyic Phaeozem, Haplic Luvisol) was studied in years 2007, 2008, 2009 and 2010. Undisturbed soil samples were taken every month to evaluate the actual field soil-water content, bulk density, porosity and hydraulic properties. The grab soil samples were taken every month to evaluate aggregate stability using the WSA (water stable aggregates) index, pHH2O and pHKCl, soil organic matter content and quality. Unsaturated hydraulic conductivity for pressure head of -2 cm was measured directly in the field using the minidisk tension infiltrometer. In addition soil structure was documented on micromorphological images. In some cases, the similar trends of the pHH2O , pHKCl , A400/A600, rod, P, θfield or WSA values were observed in different soils. Interestingly, the similar trends were found mostly for the Haplic Cambisol and the Greyic Phaeozem despite the fact that these soils considerably differed (different soil substrate, pedogenetic processes, etc.) and that variable crops (winter wheat and spring wheat) were planted at both locations during two years (2007 and 2006). Mostly different trends were observed for the Haplic Luvisol and the Greyic Phaeozem (soil of the same substrate). The reason could be attributed to a high vulnerability of the Haplic Luvisol to soil degradation in comparison to that of the Greyic Phaeozem. Parameters of hydraulic properties were highly variable and did not show similar trends for different soils (except the saturated soil water content and the slope of the retention curve at the inflection point for Haplic Cambisol and Greyic Phaeozem). Soil structure, aggregate stability and soil hydraulic properties were interrelated and depended on plant growth, rainfall compaction and tillage. The drier conditions in some soils positively influenced the soil aggregate stability, the slope of the retention curve at the inflection point and

  10. Predictors of Sustainability of Social Programs

    ERIC Educational Resources Information Center

    Savaya, Riki; Spiro, Shimon E.

    2012-01-01

    This article presents the findings of a large scale study that tested a comprehensive model of predictors of three manifestations of sustainability: continuation, institutionalization, and duration. Based on the literature the predictors were arrayed in four groups: variables pertaining to the project, the auspice organization, the community, and…