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Sample records for sample problems involving

  1. Statistical process control charts for attribute data involving very large sample sizes: a review of problems and solutions.

    PubMed

    Mohammed, Mohammed A; Panesar, Jagdeep S; Laney, David B; Wilson, Richard

    2013-04-01

    The use of statistical process control (SPC) charts in healthcare is increasing. The primary purpose of SPC is to distinguish between common-cause variation which is attributable to the underlying process, and special-cause variation which is extrinsic to the underlying process. This is important because improvement under common-cause variation requires action on the process, whereas special-cause variation merits an investigation to first find the cause. Nonetheless, when dealing with attribute or count data (eg, number of emergency admissions) involving very large sample sizes, traditional SPC charts often produce tight control limits with most of the data points appearing outside the control limits. This can give a false impression of common and special-cause variation, and potentially misguide the user into taking the wrong actions. Given the growing availability of large datasets from routinely collected databases in healthcare, there is a need to present a review of this problem (which arises because traditional attribute charts only consider within-subgroup variation) and its solutions (which consider within and between-subgroup variation), which involve the use of the well-established measurements chart and the more recently developed attribute charts based on Laney's innovative approach. We close by making some suggestions for practice. PMID:23365140

  2. ITOUGH2 sample problems

    SciTech Connect

    Finsterle, S.

    1997-11-01

    This report contains a collection of ITOUGH2 sample problems. It complements the ITOUGH2 User`s Guide [Finsterle, 1997a], and the ITOUGH2 Command Reference [Finsterle, 1997b]. ITOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media [Preuss, 1987, 1991a]. The report ITOUGH2 User`s Guide [Finsterle, 1997a] describes the inverse modeling framework and provides the theoretical background. The report ITOUGH2 Command Reference [Finsterle, 1997b] contains the syntax of all ITOUGH2 commands. This report describes a variety of sample problems solved by ITOUGH2. Table 1.1 contains a short description of the seven sample problems discussed in this report. The TOUGH2 equation-of-state (EOS) module that needs to be linked to ITOUGH2 is also indicated. Each sample problem focuses on a few selected issues shown in Table 1.2. ITOUGH2 input features and the usage of program options are described. Furthermore, interpretations of selected inverse modeling results are given. Problem 1 is a multipart tutorial, describing basic ITOUGH2 input files for the main ITOUGH2 application modes; no interpretation of results is given. Problem 2 focuses on non-uniqueness, residual analysis, and correlation structure. Problem 3 illustrates a variety of parameter and observation types, and describes parameter selection strategies. Problem 4 compares the performance of minimization algorithms and discusses model identification. Problem 5 explains how to set up a combined inversion of steady-state and transient data. Problem 6 provides a detailed residual and error analysis. Finally, Problem 7 illustrates how the estimation of model-related parameters may help compensate for errors in that model.

  3. A Few Problems Involving Scale.

    ERIC Educational Resources Information Center

    McKillip, William D.; Kay, Cynthia Stinnette

    1985-01-01

    Some applications of ratio and proportion to scale drawing involving geometric figures are given. The activities or problems concern the earth and space, scale speeds, and the earth-moon system. (MNS)

  4. Multiple Solutions Involving Geoboard Problems.

    ERIC Educational Resources Information Center

    Smith, Lyle R.

    1993-01-01

    Illustrates various methods to determine the perimeter and area of triangles and polygons formed on the geoboard. Methods utilize algebraic techniques, trigonometry, geometric theorems, and analytic geometry to solve problems and connect a variety of mathematical concepts. (MDH)

  5. Adaptive sampling for noisy problems

    SciTech Connect

    Cantu-Paz, E

    2004-03-26

    The usual approach to deal with noise present in many real-world optimization problems is to take an arbitrary number of samples of the objective function and use the sample average as an estimate of the true objective value. The number of samples is typically chosen arbitrarily and remains constant for the entire optimization process. This paper studies an adaptive sampling technique that varies the number of samples based on the uncertainty of deciding between two individuals. Experiments demonstrate the effect of adaptive sampling on the final solution quality reached by a genetic algorithm and the computational cost required to find the solution. The results suggest that the adaptive technique can effectively eliminate the need to set the sample size a priori, but in many cases it requires high computational costs.

  6. Ball-and-Stick Local Elevation Umbrella Sampling: Molecular Simulations Involving Enhanced Sampling within Conformational or Alchemical Subspaces of Low Internal Dimensionalities, Minimal Irrelevant Volumes, and Problem-Adapted Geometries.

    PubMed

    Hansen, Halvor S; Hünenberger, Philippe H

    2010-09-14

    A new method, ball-and-stick local elevation umbrella sampling (B&S-LEUS), is proposed to enhance the sampling in computer simulations of (bio)molecular systems. It enables the calculation of conformational free-energy differences between states (or alchemical free-energy differences between molecules), even in situations where the definition of these states relies on a conformational subspace involving more than a few degrees of freedom. The B&S-LEUS method consists of the following steps: (A) choice of a reduced conformational subspace; (B) representation of the relevant states by means of spheres ("balls"), each associated with a biasing potential involving a one-dimensional radial memory-based term and a radial confinement term; (C) definition of a set of lines ("sticks") connecting these spheres, each associated with a biasing potential involving a one-dimensional longitudinal memory-based term and a transverse confinement term; (D) unification of the biasing potentials corresponding to the union of all of the spheres and lines (active subspace) into a single biasing potential according to the enveloping distribution sampling (EDS) scheme; (E) build-up of the memory using the local elevation (LE) procedure, leading to a biasing potential enabling a nearly uniform sampling (radially within the spheres, longitudinally within the lines) of the active subspace; (F) generation of a biased ensemble of configurations using this preoptimized biasing potential, following an umbrella sampling (US) approach; and (G) calculation of the relative free energies of the states via reweighting and state assignment. The main characteristics of this approach are: (i) a low internal dimensionality, that is, the memory only involves one-dimensional grids (acceptable memory requirements); (ii) a minimal irrelevant volume, that is, the conformational volume opened to sampling includes a minimal fraction of irrelevant regions in terms of the free energy of the physical system or of

  7. Problems pilots face involving wind shear

    NASA Technical Reports Server (NTRS)

    Melvin, W. W.

    1977-01-01

    Educating pilots and the aviation industry about wind shears presents a major problem associated with this meteorological phenomenon. The pilot's second most pressing problem is the need for a language to discuss wind shear encounters with other pilots so that the reaction of the aircraft to the wind shear encounter can be accurately described. Another problem is the flight director which gives a centered pitch command for a given angular displacement from the glide slope. It was suggested that they should instead be called flight path command and should not center unless the aircraft is actually correcting to the flight path.

  8. iTOUGH2 Sample Problems

    SciTech Connect

    Finsterle, Stefan

    2002-06-18

    iTOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media. This report contains a collection of iTOUGH2 sample problems.

  9. 42 CFR 405.1064 - ALJ decisions involving statistical samples.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 2 2012-10-01 2012-10-01 false ALJ decisions involving statistical samples. 405... Medicare Coverage Policies § 405.1064 ALJ decisions involving statistical samples. When an appeal from the QIC involves an overpayment issue and the QIC used a statistical sample in reaching...

  10. 42 CFR 405.1064 - ALJ decisions involving statistical samples.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 2 2013-10-01 2013-10-01 false ALJ decisions involving statistical samples. 405... Medicare Coverage Policies § 405.1064 ALJ decisions involving statistical samples. When an appeal from the QIC involves an overpayment issue and the QIC used a statistical sample in reaching...

  11. 42 CFR 405.1064 - ALJ decisions involving statistical samples.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false ALJ decisions involving statistical samples. 405... Medicare Coverage Policies § 405.1064 ALJ decisions involving statistical samples. When an appeal from the QIC involves an overpayment issue and the QIC used a statistical sample in reaching...

  12. 42 CFR 405.1064 - ALJ decisions involving statistical samples.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false ALJ decisions involving statistical samples. 405... Medicare Coverage Policies § 405.1064 ALJ decisions involving statistical samples. When an appeal from the QIC involves an overpayment issue and the QIC used a statistical sample in reaching...

  13. 42 CFR 405.1064 - ALJ decisions involving statistical samples.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 2 2011-10-01 2011-10-01 false ALJ decisions involving statistical samples. 405... Medicare Coverage Policies § 405.1064 ALJ decisions involving statistical samples. When an appeal from the QIC involves an overpayment issue and the QIC used a statistical sample in reaching...

  14. Towards solving the pulsar timing sampling problem

    NASA Astrophysics Data System (ADS)

    van Haasteren, Rutger; Ellis, Justin; Vallisneri, Michele; Nanograv Collaboration

    2016-03-01

    Bayesian data analysis of Pulsar Timing Array (PTA) has proved to be a computationally challenging problem, with scaling relations that are super-linear in both the number of pulsars and the number of model parameters. Thus far, our best models cannot be used when analyzing full (international) pulsar timing array datasets in the search for gravitational waves, and shortcuts always need to be made. A promising approach in the literature, based on Hamiltonian sampling techniques, has been shown to be infeasible in realistic datasets due to phase transition behavior of the likelihood. We have introduced a coordinate transformation that mitigates this phase transition behavior, and makes Hamiltonian sampling efficient. This makes a full (stochastic) gravitational-wave search in pulsar timing data feasible with our most up-to-date models. This method scales almost linearly with the number of pulsars. Supported by NASA through Einstein fellowship PF3-140116.

  15. Parent Involvement, Emotional Support, and Behavior Problems: An Ecological Approach

    ERIC Educational Resources Information Center

    McCormick, Meghan P.; Cappella, Elise; O'Connor, Erin E.; McClowry, Sandee G.

    2013-01-01

    We examined relations between parent involvement and kindergarten students' behavior problems in classrooms with varying levels of teacher emotional support. Multi-informant data were collected on "n" = 255 low-income Black and Hispanic students, and "n" = 60 kindergarten classrooms in the baseline year of an intervention…

  16. A time domain sampling method for inverse acoustic scattering problems

    NASA Astrophysics Data System (ADS)

    Guo, Yukun; Hömberg, Dietmar; Hu, Guanghui; Li, Jingzhi; Liu, Hongyu

    2016-06-01

    This work concerns the inverse scattering problems of imaging unknown/inaccessible scatterers by transient acoustic near-field measurements. Based on the analysis of the migration method, we propose efficient and effective sampling schemes for imaging small and extended scatterers from knowledge of time-dependent scattered data due to incident impulsive point sources. Though the inverse scattering problems are known to be nonlinear and ill-posed, the proposed imaging algorithms are totally "direct" involving only integral calculations on the measurement surface. Theoretical justifications are presented and numerical experiments are conducted to demonstrate the effectiveness and robustness of our methods. In particular, the proposed static imaging functionals enhance the performance of the total focusing method (TFM) and the dynamic imaging functionals show analogous behavior to the time reversal inversion but without solving time-dependent wave equations.

  17. Longitudinal Modeling of Adolescents' Activity Involvement, Problem Peer Associations, and Youth Smoking

    ERIC Educational Resources Information Center

    Metzger, Aaron; Dawes, Nickki; Mermelstein, Robin; Wakschlag, Lauren

    2011-01-01

    Longitudinal associations among different types of organized activity involvement, problem peer associations, and cigarette smoking were examined in a sample of 1040 adolescents (mean age = 15.62 at baseline, 16.89 at 15-month assessment, 17.59 at 24 months) enriched for smoking experimentation (83% had tried smoking). A structural equation model…

  18. Externalizing and Internalizing Behavior Problems, Peer Affiliations, and Bullying Involvement across the Transition to Middle School

    ERIC Educational Resources Information Center

    Farmer, Thomas W.; Irvin, Matthew J.; Motoca, Luci M.; Leung, Man-Chi; Hutchins, Bryan C.; Brooks, Debbie S.; Hall, Cristin M.

    2015-01-01

    Continuity and change in children's involvement in bullying was examined across the transition to middle school in relation to externalizing and internalizing behavior problems in fifth grade and peer affiliations in fifth and sixth grades. The sample consisted of 533 students (223 boys, 310 girls) with 72% European American, 25% African…

  19. The New Workforce Generation: Understanding the Problems Facing Parental Involvement in Jordanian Kindergartens

    ERIC Educational Resources Information Center

    Ihmeideh, Fathi; Khasawneh, Samer; Mahfouz, Safi; Khawaldeh, Moustafa

    2008-01-01

    This study aimed to investigate the problems facing parental involvement in Jordanian kindergartens from the parents' perspectives. A 36-item questionnaire that addressed five domains was designed by the researchers and distributed among the study participants. The study sample consisted of 297 parents of kindergarten children from various…

  20. Ethnicity and bullying involvement in a national UK youth sample.

    PubMed

    Tippett, Neil; Wolke, Dieter; Platt, Lucinda

    2013-08-01

    This study investigated ethnic differences in bullying involvement (as victim and bully) among a UK wide sample of adolescents, controlling for potential confounders, including age, gender, economic situation, family structure and parent-adolescent relationships. 4668 youths, aged 10 to 15, who participate in the UK Household Longitudinal Study were assessed for bullying involvement. Binary logistic regression models were used to estimate ethnic differences across bullying roles while controlling for potential confounders. Overall, ethnic minority youths were not more likely to be victims; African boys and girls were significantly less likely to be victimised than same sex White youths. Pakistani and Caribbean girls were significantly more likely to have bullied others compared to White girls. Further research is necessary to explore why Pakistani and Caribbean girls may be more often perpetrators of bullying than girls in other ethnic groups. PMID:23849658

  1. Experimental quantum annealing: case study involving the graph isomorphism problem

    NASA Astrophysics Data System (ADS)

    Zick, Kenneth M.; Shehab, Omar; French, Matthew

    2015-06-01

    Quantum annealing is a proposed combinatorial optimization technique meant to exploit quantum mechanical effects such as tunneling and entanglement. Real-world quantum annealing-based solvers require a combination of annealing and classical pre- and post-processing; at this early stage, little is known about how to partition and optimize the processing. This article presents an experimental case study of quantum annealing and some of the factors involved in real-world solvers, using a 504-qubit D-Wave Two machine and the graph isomorphism problem. To illustrate the role of classical pre-processing, a compact Hamiltonian is presented that enables a reduced Ising model for each problem instance. On random N-vertex graphs, the median number of variables is reduced from N2 to fewer than N log2 N and solvable graph sizes increase from N = 5 to N = 13. Additionally, error correction via classical post-processing majority voting is evaluated. While the solution times are not competitive with classical approaches to graph isomorphism, the enhanced solver ultimately classified correctly every problem that was mapped to the processor and demonstrated clear advantages over the baseline approach. The results shed some light on the nature of real-world quantum annealing and the associated hybrid classical-quantum solvers.

  2. Experimental quantum annealing: case study involving the graph isomorphism problem

    PubMed Central

    Zick, Kenneth M.; Shehab, Omar; French, Matthew

    2015-01-01

    Quantum annealing is a proposed combinatorial optimization technique meant to exploit quantum mechanical effects such as tunneling and entanglement. Real-world quantum annealing-based solvers require a combination of annealing and classical pre- and post-processing; at this early stage, little is known about how to partition and optimize the processing. This article presents an experimental case study of quantum annealing and some of the factors involved in real-world solvers, using a 504-qubit D-Wave Two machine and the graph isomorphism problem. To illustrate the role of classical pre-processing, a compact Hamiltonian is presented that enables a reduced Ising model for each problem instance. On random N-vertex graphs, the median number of variables is reduced from N2 to fewer than N log2 N and solvable graph sizes increase from N = 5 to N = 13. Additionally, error correction via classical post-processing majority voting is evaluated. While the solution times are not competitive with classical approaches to graph isomorphism, the enhanced solver ultimately classified correctly every problem that was mapped to the processor and demonstrated clear advantages over the baseline approach. The results shed some light on the nature of real-world quantum annealing and the associated hybrid classical-quantum solvers. PMID:26053973

  3. Decision and function problems based on boson sampling

    NASA Astrophysics Data System (ADS)

    Nikolopoulos, Georgios M.; Brougham, Thomas

    2016-07-01

    Boson sampling is a mathematical problem that is strongly believed to be intractable for classical computers, whereas passive linear interferometers can produce samples efficiently. So far, the problem remains a computational curiosity, and the possible usefulness of boson-sampling devices is mainly limited to the proof of quantum supremacy. The purpose of this work is to investigate whether boson sampling can be used as a resource of decision and function problems that are computationally hard, and may thus have cryptographic applications. After the definition of a rather general theoretical framework for the design of such problems, we discuss their solution by means of a brute-force numerical approach, as well as by means of nonboson samplers. Moreover, we estimate the sample sizes required for their solution by passive linear interferometers, and it is shown that they are independent of the size of the Hilbert space.

  4. Comorbid Problem Gambling and Major Depression in a Community Sample.

    PubMed

    Quigley, Leanne; Yakovenko, Igor; Hodgins, David C; Dobson, Keith S; El-Guebaly, Nady; Casey, David M; Currie, Shawn R; Smith, Garry J; Williams, Robert J; Schopflocher, Don P

    2015-12-01

    Major depression is among the most common comorbid conditions in problem gambling. However, little is known about the effects of comorbid depression on problem gambling. The present study examined the prevalence of current major depression among problem gamblers (N = 105) identified from a community sample of men and women in Alberta, and examined group differences in gambling severity, escape motivation for gambling, family functioning, childhood trauma, and personality traits across problem gamblers with and without comorbid depression. The prevalence of major depression among the sample of problem gamblers was 32.4%. Compared to problem gamblers without depression (n = 71), problem gamblers with comorbid depression (n = 34) reported more severe gambling problems, greater history of childhood abuse and neglect, poorer family functioning, higher levels of neuroticism, and lower levels of extraversion, agreeableness, and conscientiousness. Furthermore, the problem gamblers with comorbid depression had greater levels of childhood abuse and neglect, worse family functioning, higher neuroticism, and lower agreeableness and conscientiousness than a comparison sample of recreational gamblers with depression (n = 160). These findings underscore the need to address comorbid depression in assessment and treatment of problem gambling and for continued research on how problem gambling is related to frequently co-occurring disorders such as depression. PMID:25112217

  5. Droplet Breakup and Other Problems Involving Surface Tension Driven Flows.

    NASA Astrophysics Data System (ADS)

    Brenner, Michael P.

    We explore several problems involving fluid flows driven by surface tension. The first part of the thesis concerns droplet breakup. The major focus is on the formation of singularities occurring when a mass of fluid breaks into two pieces. We explore this phenomena in many different physical situations, including droplet breakup in a Hele Shaw cell, rupturing of thin films on a solid surface, the breaking of Plateau borders in soap froths, and fluid dripping from a cylindrical nozzle. In most of the above examples the singularities are characterized by self similar solutions of nonlinear partial differential equations. For the dripping faucet, the similarity solution is unstable to finite (but small) amplitude perturbations; the consequence of this is that in practice the breakup of a three dimensional droplet is a nonsteady process, with new structures continually generated as the interface breaks. Through asymptotic analysis, we show that the amount of noise necessary to destabilize the similarity solution decreases rapidly as the singularity is approached. For fluids of moderate viscosity fluctuations in the interfacial shape of atomic size are sufficient to destabilize the interface when the thickness is less than one micron. The second part of the thesis addresses problems in wetting. We present an analysis of a droplet spreading on a solid surface, which results in an understanding of the experimentally observed spreading laws. Finally, we present an explanation of the mechanism for the instability that occurs when a contact line is driven by a constant force. The explanation is consistent with recent experimental data.

  6. Solving probabilistic inverse problems rapidly with prior samples

    NASA Astrophysics Data System (ADS)

    Käufl, Paul; Valentine, Andrew; De Wit, Ralph; Trampert, Jeannot

    2016-03-01

    Owing to the increasing availability of computational resources, in recent years the probabilistic solution of non-linear, geophysical inverse problems by means of sampling methods has become increasingly feasible. Nevertheless, we still face situations in which a Monte Carlo approach is not practical. This is particularly true in cases where the evaluation of the forward problem is computationally intensive or where inversions have to be carried out repeatedly or in a timely manner, as in natural hazards monitoring tasks such as earthquake early warning. Here, we present an alternative to Monte Carlo sampling, in which inferences are entirely based on a set of prior samples-i.e. samples that have been obtained independent of a particular observed datum. This has the advantage that the computationally expensive sampling stage becomes separated from the inversion stage, and the set of prior samples-once obtained-can be reused for repeated evaluations of the inverse mapping without additional computational effort. This property is useful if the problem is such that repeated inversions of independent data have to be carried out. We formulate the inverse problem in a Bayesian framework and present a practical way to make posterior inferences based on a set of prior samples. We compare the prior sampling based approach to a Markov Chain Monte Carlo approach that samples from the posterior probability distribution. We show results for both a toy example, and a realistic seismological source parameter estimation problem. We find that the posterior uncertainty estimates obtained based on prior sampling can be considered conservative estimates of the uncertainties obtained by directly sampling from the posterior distribution.

  7. Solving probabilistic inverse problems rapidly with prior samples

    NASA Astrophysics Data System (ADS)

    Käufl, Paul; Valentine, Andrew P.; de Wit, Ralph W.; Trampert, Jeannot

    2016-06-01

    Owing to the increasing availability of computational resources, in recent years the probabilistic solution of non-linear, geophysical inverse problems by means of sampling methods has become increasingly feasible. Nevertheless, we still face situations in which a Monte Carlo approach is not practical. This is particularly true in cases where the evaluation of the forward problem is computationally intensive or where inversions have to be carried out repeatedly or in a timely manner, as in natural hazards monitoring tasks such as earthquake early warning. Here, we present an alternative to Monte Carlo sampling, in which inferences are entirely based on a set of prior samples-that is, samples that have been obtained independent of a particular observed datum. This has the advantage that the computationally expensive sampling stage becomes separated from the inversion stage, and the set of prior samples-once obtained-can be reused for repeated evaluations of the inverse mapping without additional computational effort. This property is useful if the problem is such that repeated inversions of independent data have to be carried out. We formulate the inverse problem in a Bayesian framework and present a practical way to make posterior inferences based on a set of prior samples. We compare the prior sampling based approach to a Markov Chain Monte Carlo approach that samples from the posterior probability distribution. We show results for both a toy example, and a realistic seismological source parameter estimation problem. We find that the posterior uncertainty estimates obtained based on prior sampling can be considered conservative estimates of the uncertainties obtained by directly sampling from the posterior distribution.

  8. Efficient infill sampling for unconstrained robust optimization problems

    NASA Astrophysics Data System (ADS)

    Rehman, Samee Ur; Langelaar, Matthijs

    2016-08-01

    A novel infill sampling criterion is proposed for efficient estimation of the global robust optimum of expensive computer simulation based problems. The algorithm is especially geared towards addressing problems that are affected by uncertainties in design variables and problem parameters. The method is based on constructing metamodels using Kriging and adaptively sampling the response surface via a principle of expected improvement adapted for robust optimization. Several numerical examples and an engineering case study are used to demonstrate the ability of the algorithm to estimate the global robust optimum using a limited number of expensive function evaluations.

  9. Strategies, Not Solutions: Involving Students in Problem Solving.

    ERIC Educational Resources Information Center

    Von Kuster, Lee N.

    1984-01-01

    Defines problem solving, discusses the use of problems developed by students that are relevant to their own lives, presents examples of practical mathematics problems that deal with local situations, discusses fringe benefits of this type of problem solving, and addresses teachers' concern that this method consumes too much time. (MBR)

  10. Analyzing the many skills involved in solving complex physics problems

    NASA Astrophysics Data System (ADS)

    Adams, Wendy K.; Wieman, Carl E.

    2015-05-01

    We have empirically identified over 40 distinct sub-skills that affect a person's ability to solve complex problems in many different contexts. The identification of so many sub-skills explains why it has been so difficult to teach or assess problem solving as a single skill. The existence of these sub-skills is supported by several studies comparing a wide range of individuals' strengths and weaknesses in these sub-skills, their "problem solving fingerprint," while solving different types of problems including a classical mechanics problem, quantum mechanics problems, and a complex trip-planning problem with no physics. We see clear differences in the problem solving fingerprint of physics and engineering majors compared to the elementary education majors that we tested. The implications of these findings for guiding the teaching and assessing of problem solving in physics instruction are discussed.

  11. Crack problems involving nonhomogeneous interfacial regions in bonded materials

    NASA Technical Reports Server (NTRS)

    Erdogan, F.

    1990-01-01

    Consideration is given to two classes of fracture-related solid mechanics problems in which the model leads to some physically anomalous results. The first is the interface crack problem associated with the debonding process in which the corresponding elasticity solution predicts severe oscillations of stresses and the crack surface displacements vary near the crack tip. The second deals with crack intersecting the interface. The nature of the solutions around the crack tips arising from these problems is reviewed. The rationale for introducing a new interfacial zone model is discussed, its analytical consequences within the context of the two crack-problem classes are described, and some examples are presented.

  12. An Experience Sampling Study of PTSD and Alcohol Related Problems

    PubMed Central

    Gaher, Raluca M.; Simons, Jeffrey S.; Hahn, Nicole L; Hofman, Jamie Hansen; Hofman, Jamie Hansen; Buchkoski, Jerome

    2014-01-01

    Posttraumatic stress disorder (PTSD) represents a debilitating psychiatric condition that is affecting the lives of many returning veterans. PTSD and alcohol use and dependence are highly comorbid. The purpose of this study was to understand the functional mechanisms between PTSD and alcohol use and problems. Specifically, the role of negative urgency and emotional intelligence were investigated as vulnerability and resiliency factors, respectively. This study utilized experience sampling to test associations between PTSD symptoms and alcohol use and related problems in a sample of 90 OIF/OEF veterans. Participants completed eight brief questionnaires daily for two weeks on palmtop computers. Elevations in PTSD symptoms during the day were associated with subsequent increases in alcohol use and associated problems that night. PTSD symptoms were associated with greater problems above and beyond the effect of drinking level at both the within- and between- person level. Emotional intelligence was associated with lower negative urgency, fewer PTSD symptoms, and less alcohol use and associated problems. The effects of emotional intelligence were primarily indirect via negative urgency and the effects of negative urgency on alcohol use and problems were indirect via its positive association with PTSD symptoms. Hypothesized cross-level effects of emotional intelligence and negative urgency were not supported. The findings suggest a functional association between PTSD symptoms and alcohol consumption. The association between PTSD symptoms and alcohol consumption is consistent with a self-medication model. However, the significant associations between PTSD symptoms and alcohol problems, after controlling for use level, suggest a broader role of dysregulation. PMID:25134021

  13. Problems of sampling and radiation balances: Their problematics

    NASA Technical Reports Server (NTRS)

    Crommelynck, D.

    1980-01-01

    Problems associated with the measurement of the Earth radiation balances are addressed. It is demonstrated that the knowledge of the different radiation budgets with their components is largely dependent on the space time sampling of the radiation field of the Earth atmosphere system. Whichever instrumental approach is adopted (wide angle view of high resolution) it affects the space time integration of the fluxes measured directly or calculated. In this case the necessary knowledge of the reflection pattern depends in addition on the angular sampling of the radiances. A series of questions is considered, the answers of which are a prerequisite to the the organization of a global observation system.

  14. Unresolved Issues in Adult Children's Marital Relationships Involving Intergenerational Problems.

    ERIC Educational Resources Information Center

    Beaton, John M.; Norris, Joan E.; Pratt, Michael W.

    2003-01-01

    When their first child was 5, 30 couples discussed an unresolved issue in their marital relationship that involved one of their parents, and how they would resolve this issue. Five intergenerational themes were identified in these disagreements: balancing nuclear vs. extended family time, changing rules and roles, pleasing parents vs. spouse,…

  15. The Relationship Between Father Involvement and Child Problem Behaviour in Intact Families: A 7-Year Cross-Lagged Study.

    PubMed

    Flouri, Eirini; Midouhas, Emily; Narayanan, Martina K

    2016-07-01

    This study investigated the cross-lagged relationship between father involvement and child problem behaviour across early-to-middle childhood, and tested whether temperament modulated any cross-lagged child behaviour effects on father involvement. It used data from the first four waves of the UK's Millennium Cohort Study, when children (50.3 % male) were aged 9 months, and 3, 5 and 7 years. The sample was 8302 families where both biological parents were co-resident across the four waves. Father involvement (participation in play and physical and educational activities with the child) was measured at ages 3, 5 and 7, as was child problem behaviour (assessed with the Strengths and Difficulties Questionnaire). Key child and family covariates related to father involvement and child problem behaviour were controlled. Little evidence was found that more father involvement predicted less child problem behaviour two years later, with the exception of father involvement at child's age 5 having a significant, but small, effect on peer problems at age 7. There were two child effects. More hyperactive children at age 3 had more involved fathers at age 5, and children with more conduct problems at age 3 had more involved fathers at age 5. Child temperament did not moderate any child behaviour effects on father involvement. Thus, in young, intact UK families, child adjustment appears to predict, rather than be predicted by, father involvement in early childhood. When children showed more problematic behaviours, fathers did not become less involved. In fact, early hyperactivity and conduct problems in children seemed to elicit more involvement from fathers. At school age, father involvement appeared to affect children's social adjustment rather than vice versa. PMID:26349744

  16. Advanced Curation: Solving Current and Future Sample Return Problems

    NASA Technical Reports Server (NTRS)

    Fries, M.; Calaway, M.; Evans, C.; McCubbin, F.

    2015-01-01

    Advanced Curation is a wide-ranging and comprehensive research and development effort at NASA Johnson Space Center that identifies and remediates sample related issues. For current collections, Advanced Curation investigates new cleaning, verification, and analytical techniques to assess their suitability for improving curation processes. Specific needs are also assessed for future sample return missions. For each need, a written plan is drawn up to achieve the requirement. The plan draws while upon current Curation practices, input from Curators, the analytical expertise of the Astromaterials Research and Exploration Science (ARES) team, and suitable standards maintained by ISO, IEST, NIST and other institutions. Additionally, new technologies are adopted on the bases of need and availability. Implementation plans are tested using customized trial programs with statistically robust courses of measurement, and are iterated if necessary until an implementable protocol is established. Upcoming and potential NASA missions such as OSIRIS-REx, the Asteroid Retrieval Mission (ARM), sample return missions in the New Frontiers program, and Mars sample return (MSR) all feature new difficulties and specialized sample handling requirements. The Mars 2020 mission in particular poses a suite of challenges since the mission will cache martian samples for possible return to Earth. In anticipation of future MSR, the following problems are among those under investigation: What is the most efficient means to achieve the less than 1.0 ng/sq cm total organic carbon (TOC) cleanliness required for all sample handling hardware? How do we maintain and verify cleanliness at this level? The Mars 2020 Organic Contamination Panel (OCP) predicts that organic carbon, if present, will be present at the "one to tens" of ppb level in martian near-surface samples. The same samples will likely contain wt% perchlorate salts, or approximately 1,000,000x as much perchlorate oxidizer as organic carbon

  17. Sampling problems: The small scale structure of precipitation

    NASA Technical Reports Server (NTRS)

    Crane, R. K.

    1981-01-01

    The quantitative measurement of precipitation characteristics for any area on the surface of the Earth is not an easy task. Precipitation is rather variable in both space and time, and the distribution of surface rainfall data given location typically is substantially skewed. There are a number of precipitation process at work in the atmosphere, and few of them are well understood. The formal theory on sampling and estimating precipitation appears considerably deficient. Little systematic attention is given to nonsampling errors that always arise in utilizing any measurement system. Although the precipitation measurement problem is an old one, it continues to be one that is in need of systematic and careful attention. A brief history of the presently competing measurement technologies should aid us in understanding the problem inherent in this measurement task.

  18. Defining the Mars Ascent Problem for Sample Return

    SciTech Connect

    Whitehead, J

    2008-07-31

    Lifting geology samples off of Mars is both a daunting technical problem for propulsion experts and a cultural challenge for the entire community that plans and implements planetary science missions. The vast majority of science spacecraft require propulsive maneuvers that are similar to what is done routinely with communication satellites, so most needs have been met by adapting hardware and methods from the satellite industry. While it is even possible to reach Earth from the surface of the moon using such traditional technology, ascending from the surface of Mars is beyond proven capability for either solid or liquid propellant rocket technology. Miniature rocket stages for a Mars ascent vehicle would need to be over 80 percent propellant by mass. It is argued that the planetary community faces a steep learning curve toward nontraditional propulsion expertise, in order to successfully accomplish a Mars sample return mission. A cultural shift may be needed to accommodate more technical risk acceptance during the technology development phase.

  19. Association between parenthood and problem behavior in a national sample of adolescents.

    PubMed

    Elster, A B; Ketterlinus, R; Lamb, M E

    1990-06-01

    The association between problem behaviors and parental status was studied in a national sample of urban (n = 1263) and rural (n = 388) young women 15 to 17 years of age. When assessed according to age at childbearing, there was a clear association between problem behavior and the birth of a first child prior to age 19 years. The three parental status groups studied appeared ordered in risk, with school-aged mothers having engaged in the most problem behaviors, and followed, in turn, by young adult mothers (ie, those who had a child between 19 and 21 years of age), and then by women who had not had a child by age 21 years. Young urban women who engaged in three or more problem behaviors were more likely than women who claimed no involvement in problem behaviors to subsequently have a child prior to age 19 years. In addition, black adolescents reported fewer problem behaviors than did white adolescents. When individual behaviors were analyzed, school-aged mothers were more likely than either young adult mothers or nonmothers to have reported school suspension, truancy, runaway, smoking marijuana, and fighting. Although similar results were found in both samples, the effects appeared more consistent for young urban women. In future studies, researchers must determine whether adolescent mothers are at risk for parenting difficulties because of their previous involvement in problem behaviors. PMID:2339028

  20. Organic nitrogen in precipitation: real problem or sampling artefact?

    PubMed

    Cape, J N; Kirika, A; Rowland, A P; Wilson, D R; Jickells, T D; Cornell, S

    2001-11-01

    Published observations of organic nitrogen (N) compounds in precipitation go back almost a century. Several different methods have been used to measure both the total and ionic concentrations of N. There is therefore some uncertainty as to whether reported "organic N" is real, or simply the result of uncertainties in chemical analyses or inadequate sampling methods. We found that the materials from which the collector was made (polypropylene, steel, or glass) had no significant effect on the composition of dissolved organic N (DON). The use of a biocide was found to be very important during sampling and storage of samples before analysis. We set up a network of seven collectors across the U.K., from the Cairngorms to Dorset, all operating to the same protocol, and including a biocide. Samples were analysed centrally, using proven methods. Over 6 months, organic N contributed about 20% to the total N in U.K. precipitation, but with a large variation across the country. This means that current estimates of wet deposited N to the U.K., which are based only on the ammonium and nitrate concentrations, are too small. Organic N is not an artefact, but a real problem that needs to be addressed. PMID:12805792

  1. Problem drinking and the dimension of involvement with drugs: a Guttman scalogram analysis of adolescent drug use.

    PubMed Central

    Donovan, J E; Jessor, R

    1983-01-01

    Analyses of data from two nationwide surveys of high school students, one carried out in 1974 and the other in 1978, suggest that problem drinking may be seen as yet another step along an underlying dimension of involvement with both licit and illicit drugs. The dimension of involvement with drugs consists of the following levels: nonuse of alcohol or illicit drugs; nonproblem use of alcohol; marijuana use; problem drinking; use of pills (amphetamines, barbiturates, hallucinogenic drugs); and the use of "hard drugs" such as cocaine or heroin. The dimension possesses excellent Guttman-scale properties in both national samples as well as in subsamples differing in gender and ethnic background. The ordering of the levels of involvement was confirmed by the ordering of the alcohol-drug involvement groups based on their mean scores on measures of psychosocial proneness for involvement in problem behavior. The excessive use of a licit drug, i.e., problem drinking, appears to indicate greater involvement in drug use than does the use of an illicit drug, marijuana. This finding points to the importance of distinguishing between use and problem use of drugs in efforts to understand adolescent drug involvement. PMID:6837819

  2. Effect of scaffolding on helping introductory physics students solve quantitative problems involving strong alternative conceptions

    NASA Astrophysics Data System (ADS)

    Lin, Shih-Yin; Singh, Chandralekha

    2015-12-01

    It is well known that introductory physics students often have alternative conceptions that are inconsistent with established physical principles and concepts. Invoking alternative conceptions in the quantitative problem-solving process can derail the entire process. In order to help students solve quantitative problems involving strong alternative conceptions correctly, appropriate scaffolding support can be helpful. The goal of this study is to examine how different scaffolding supports involving analogical problem-solving influence introductory physics students' performance on a target quantitative problem in a situation where many students' solution process is derailed due to alternative conceptions. Three different scaffolding supports were designed and implemented in calculus-based and algebra-based introductory physics courses involving 410 students to evaluate the level of scaffolding needed to help students learn from an analogical problem that is similar in the underlying principles involved but for which the problem-solving process is not derailed by alternative conceptions. We found that for the quantitative problem involving strong alternative conceptions, simply guiding students to work through the solution of the analogical problem first was not enough to help most students discern the similarity between the two problems. However, if additional scaffolding supports that directly helped students examine and repair their knowledge elements involving alternative conceptions were provided, e.g., by guiding students to contemplate related issues and asking them to solve the targeted problem on their own first before learning from the analogical problem provided, students were more likely to discern the underlying similarities between the problems and avoid getting derailed by alternative conceptions when solving the targeted problem. We also found that some scaffolding supports were more effective in the calculus-based course than in the algebra

  3. Child Involvement in Interparental Conflict and Child Adjustment Problems: A Longitudinal Study of Violent Families

    PubMed Central

    Jouriles, Ernest N.; Rosenfield, David; McDonald, Renee; Mueller, Victoria

    2014-01-01

    This study examined whether child involvement in interparental conflict predicts child externalizing and internalizing problems in violent families. Participants were 119 families (mothers and children) recruited from domestic violence shelters. One child between the ages of 7 and 10 years in each family (50 female, 69 male) completed measures of involvement in their parents’ conflicts, externalizing problems, and internalizing problems. Mothers completed measures of child externalizing and internalizing problems, and physical intimate partner violence. Measures were completed at three assessments, spaced 6 months apart. Results indicated that children’s involvement in their parents’ conflicts was positively associated with child adjustment problems. These associations emerged in between-subjects and within-subjects analyses, and for child externalizing as well as internalizing problems, even after controlling for the influence of physical intimate partner violence. In addition, child involvement in parental conflicts predicted later child reports of externalizing problems, but child reports of externalizing problems did not predict later involvement in parental conflicts. These findings highlight the importance of considering children’s involvement in their parents’ conflicts in theory and clinical work pertaining to high-conflict families. PMID:24249486

  4. On the continuous dependence with respect to sampling of the linear quadratic regulator problem for distributed parameter systems

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.; Wang, C.

    1990-01-01

    The convergence of solutions to the discrete or sampled time linear quadratic regulator problem and associated Riccati equation for infinite dimensional systems to the solutions to the corresponding continuous time problem and equation, as the length of the sampling interval (the sampling rate) tends toward zero (infinity) is established. Both the finite and infinite time horizon problems are studied. In the finite time horizon case, strong continuity of the operators which define the control system and performance index together with a stability and consistency condition on the sampling scheme are required. For the infinite time horizon problem, in addition, the sampled systems must be stabilizable and detectable, uniformly with respect to the sampling rate. Classes of systems for which this condition can be verified are discussed. Results of numerical studies involving the control of a heat/diffusion equation, a hereditary of delay system, and a flexible beam are presented and discussed.

  5. On the continuous dependence with respect to sampling of the linear quadratic regulator problem for distributed parameter system

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.; Wang, C.

    1992-01-01

    The convergence of solutions to the discrete- or sampled-time linear quadratic regulator problem and associated Riccati equation for infinite-dimensional systems to the solutions to the corresponding continuous time problem and equation, as the length of the sampling interval (the sampling rate) tends toward zero(infinity) is established. Both the finite-and infinite-time horizon problems are studied. In the finite-time horizon case, strong continuity of the operators that define the control system and performance index, together with a stability and consistency condition on the sampling scheme are required. For the infinite-time horizon problem, in addition, the sampled systems must be stabilizable and detectable, uniformly with respect to the sampling rate. Classes of systems for which this condition can be verified are discussed. Results of numerical studies involving the control of a heat/diffusion equation, a hereditary or delay system, and a flexible beam are presented and discussed.

  6. A fixed grid numerical methodology for phase change problems involving a moving heat source

    NASA Technical Reports Server (NTRS)

    Prakash, C.; Samonds, M.; Singhal, A. K.

    1987-01-01

    A numerical method for solving phase change problems involving a moving heat source is presented and illustrated by a two-dimensional example. The method uses a fixed grid and does not require the implementation of the Stefan condition at the solid-liquid interface; the procedure can thus be easily implemented using existing fixed grid codes. The problem considered as an example involves natural convection flow in the molten metal during tungsten inert gas welding.

  7. Examining Masculinity Norms, Problem Drinking, and Athletic Involvement as Predictors of Sexual Aggression in College Men

    ERIC Educational Resources Information Center

    Locke, Benjamin D.; Mahalik, James R.

    2005-01-01

    Male sexual aggression toward women is a serious social problem, particularly on college campuses. In this study, college men's sexually aggressive behavior and rape myth acceptance were examined using conformity to 11 masculine norms and 2 variables previously linked to sexual aggression: problem drinking and athletic involvement. Results…

  8. Effect of Scaffolding on Helping Introductory Physics Students Solve Quantitative Problems Involving Strong Alternative Conceptions

    ERIC Educational Resources Information Center

    Lin, Shih-Yin; Singh, Chandralekha

    2015-01-01

    It is well known that introductory physics students often have alternative conceptions that are inconsistent with established physical principles and concepts. Invoking alternative conceptions in the quantitative problem-solving process can derail the entire process. In order to help students solve quantitative problems involving strong…

  9. A Model for Involving Parents of Children with Learning and Behavior Problems in the Schools

    ERIC Educational Resources Information Center

    Darch, Craig; Miao, Yu; Shippen, Peggy

    2004-01-01

    The authors present a practical model for including parents of children with learning and behavior problems in the schools. First, characteristics of families with children with learning and behavior problems are discussed. Next, 4 features of an effective program to involve parents are presented. These features are: (a) proactive design, (b)…

  10. Family Involvement in Preschool Education: Rationale, Problems and Solutions for the Participants

    ERIC Educational Resources Information Center

    Kocyigit, Sinan

    2015-01-01

    This aim of this study is to examine the views of teachers, administrators and parents about the problems that emerge during family involvement in preschool activities and solutions for these problems. The participants were 10 teachers, 10 parents and 10 administrators from 4 preschools and 6 kindergartens in the Palandöken and Yakutiye districts…

  11. COMPARISON OF BIOLOGICAL COMMUNITIES: THE PROBLEM OF SAMPLE REPRESENTATIVENESS

    EPA Science Inventory

    Obtaining an adequate, representative sample of biological communities or assemblages to make richness or compositional comparisons among sites is a continuing challenge. Traditionally, sample size is based on numbers of replicates or area collected or numbers of individuals enum...

  12. Problem Solving Process Research of Everyone Involved in Innovation Based on CAI Technology

    NASA Astrophysics Data System (ADS)

    Chen, Tao; Shao, Yunfei; Tang, Xiaowo

    It is very important that non-technical department personnel especially bottom line employee serve as innovators under the requirements of everyone involved in innovation. According the view of this paper, it is feasible and necessary to build everyone involved in innovation problem solving process under Total Innovation Management (TIM) based on the Theory of Inventive Problem Solving (TRIZ). The tools under the CAI technology: How TO mode and science effects database could be very useful for all employee especially non-technical department and bottom line for innovation. The problem solving process put forward in the paper focus on non-technical department personnel especially bottom line employee for innovation.

  13. Modeling problem behaviors in a nationally representative sample of adolescents.

    PubMed

    O'Connor, Kate L; Dolphin, Louise; Fitzgerald, Amanda; Dooley, Barbara

    2016-07-01

    Research on multiple problem behaviors has focused on the concept of Problem Behavior Syndrome (PBS). Problem Behavior Theory (PBT) is a complex and comprehensive social-psychological framework designed to explain the development of a range of problem behaviors. This study examines the structure of PBS and the applicability of PBT in adolescents. Participants were 6062 adolescents; aged 12-19 (51.3% female) who took part in the My World Survey-Second Level (MWS-SL). Regarding PBS, Confirmatory Factor Analysis established that problem behaviors, such as alcohol and drug use loaded significantly onto a single, latent construct for males and females. Using Structural Equation Modeling, the PBT framework was found to be a good fit for males and females. Socio-demographic, perceived environment system and personality accounted for over 40% of the variance in problem behaviors for males and females. Our findings have important implications for understanding how differences in engaging in problem behaviors vary by gender. PMID:27161989

  14. Mediators of the relationship between religiousness/spirituality and alcohol problems in an adult community sample.

    PubMed

    Drerup, Michelle L; Johnson, Thomas J; Bindl, Stephen

    2011-12-01

    Johnson et al. (2008b) reported that, in a college student sample, the effect of religiousness on alcohol use was mediated by negative beliefs about alcohol, social influences, and spiritual well-being, and that these variables in turn impacted alcohol use and problems both directly and indirectly via motives for drinking. This study attempted to replicate those findings in a sample of community dwelling adults (N=211). The effect of Religious/Spiritual Involvement was mediated by Negative Beliefs about Alcohol, Social Modeling, and Spiritual-Well-Being. However, Social Modeling had stronger relationships with motives for drinking and alcohol consumption than the other two mediators. The effect of Religious Struggle on Alcohol Problems was mediated by Spiritual Well-Being and coping motives for drinking. Results provide further support for the motivational model of alcohol use and suggest plausible mechanisms by which religiousness could causally impact alcohol use and problems. Religious struggle may be a clinically significant correlate of alcohol problems. PMID:21868169

  15. Influence of mother's depression on her reports of father involvement and child behavioral problems: a latent state-trait approach.

    PubMed

    Raskin, Maryna; Fosse, Nathan E; Easterbrooks, M Ann

    2015-01-01

    Research on father involvement has shown positive effects on child development. Because fathers in high social risk samples may be hard to recruit or retain in studies, the literature often has relied on maternal report of father involvement. A major limitation of this approach is that unobserved traits of the reporting mothers may distort the real associations between father involvement and children's development. Using maternal data from a large, longitudinal sample (N = 704) of low-income, young mothers, we evaluated the degree to which a stable depressive trait affected the link between mother-reported measures of father involvement and child problems. Three waves of maternal depression data were used to fit a latent state-trait model of depression, allowing for separate estimates of occasion-specific symptoms and stable depressive trait. A latent regression analysis which did not control for this trait revealed a link between father involvement and child problems similar in magnitude to the links reported in the literature. However, this association disappeared once we accounted for the effect of maternal depressive trait. Results suggest that studies using maternal reports of both father and child behaviors should control for such confounding effects. We elaborate on these findings in the conclusion and offer suggestions for future research on the role of fathers in child development. PMID:25504511

  16. An empirical coverage test for the g-sample problem

    USGS Publications Warehouse

    Orlowski, L.A.; Grundy, W.D.; Mielke, P.W., Jr.

    1991-01-01

    A nonparametric g-sample empirical coverage test has recently been developed for univariate continuous data. It is based upon the empirical coverages which are spacings of multiple random samples. The test is capable of detecting any distributional differences which may exist among the parent populations, without additional assumptions beyond randomness and continuity. The test can be effective with the limited and/or unequal sample sizes most often encountered in geologic studies. A computer program for implementing this procedure, G-SECT 1, is available. ?? 1991 International Association for Mathematical Geology.

  17. Communication Problems in Turner Syndrome: A Sample Survey.

    ERIC Educational Resources Information Center

    Van Borsel, John; Dhooge, Inge; Verhoye, Kristof; Derde, Kristel; Curfs, Leopold

    1999-01-01

    A survey of 128 females (ages 2-58) with Turner syndrome found almost one quarter were receiving or had received treatment for stuttering, articulation problems, and/or delayed language development, with the latter two disorders being checked most frequently. Only 4 or the 68 individuals receiving growth hormone treatment reported voice changes.…

  18. A Sample Time Optimization Problem in a Digital Control System

    NASA Astrophysics Data System (ADS)

    Mitkowski, Wojciech; Oprzędkiewicz, Krzysztof

    In the paper a phenomenon of the existence of a sample time minimizing the settling time in a digital control system is described. As a control plant an experimental heat object was used. The control system was built with the use of a soft PLC system SIEMENS SIMATIC. As the control algorithm a finite dimensional dynamic compensator was applied. During tests of the control system it was observed that there exists a value of the sample time which minimizes the settling time in the system. This phenomenon is tried to explain.

  19. Maternal Depressive Symptoms and Child Behavior Problems among Latina Adolescent Mothers: The Buffering Effect of Mother-Reported Partner Child Care Involvement

    ERIC Educational Resources Information Center

    Smith, Erin N.; Grau, Josefina M.; Duran, Petra A.; Castellanos, Patricia

    2013-01-01

    We examined the relations between maternal depressive symptoms and child internalizing and externalizing problems in a sample of 125 adolescent Latina mothers (primarily Puerto Rican) and their toddlers. We also tested the influence of mother-reported partner child care involvement on child behavior problems and explored mother-reported partner…

  20. Adolescents' Viewing of Suicide-Related Web Content and Psychological Problems: Differentiating the Roles of Cyberbullying Involvement.

    PubMed

    Görzig, Anke

    2016-08-01

    Possible links of cyberbullying with suicide and psychological problems have recently received considerable attention. Suicide-related behaviors have also been linked with viewing of associated web content. Studies on traditional bullying indicate that the roles of bullying involvement (bullies, victims, and bully-victims) matter in terms of associations with specific suicide-related behaviors and psychological problems. Yet, related research in the area of cyberbullying is lacking. The current study investigates the association of cyberbullying roles with viewing of specific suicide-related web content and psychological problems. Data from N = 19,406 (50 percent girls) 11-16-year-olds (M = 13.54, SD = 1.68) of a representative sample of Internet-using children in Europe were analyzed. Self-reports were obtained for cyberbullying role, viewing of web content related to self-harm, and suicide, as well as the emotional, peer, and conduct problem subscales of the Strengths and Difficulties Questionnaire (SDQ). Multinomial logistic regression analyses revealed that compared with those not involved in cyberbullying, viewing of web content related to suicide was higher for cybervictims and cyberbully-victims, but not for cyberbullies. Viewing of web content related to self-harm was higher for all cyberbullying roles, especially for cyberbully-victims. Rates of emotional problems were higher among cybervictims and cyberbully-victims, rates of peer problems were higher for cybervictims, and rates of conduct problems were higher for all cyberbullying roles. Moreover, the links between cyberbullying role and viewing of suicide-related web content were independent of psychological problems. The results can be useful to more precisely target efforts toward the specific problems of each cyberbullying role. The outcomes on viewing of web content also indicate an opportunity to enhance the presence of health service providers on Internet platforms. PMID:27448043

  1. Finite element simulations involving simultaneous multiple interface fronts in phase change problems

    NASA Technical Reports Server (NTRS)

    Ouyang, Tianhong; Tamma, Kumar K.

    1992-01-01

    The present paper describes the simulation of phase change problems involving simultaneous multiple interface fronts employing the finite element method. Much of the past investigations employing finite elements have been restricted to primarily a single phase change situation. The existence of more than one phase, that is, the presence of multiple phase fronts poses certain challenges and further complications. However, the results provide a very interesting thermal behavior for this class of problems. In this paper, attention is focused on fixed grid methods and the trapezoidal family of one-step methods using the enthalpy formulations. Illustrative examples which handle simultaneous multiple fronts in phase change problems are presented.

  2. Risky Alcohol Use, Peer and Family Relationships and Legal Involvement in Adolescents with Antisocial Problems

    ERIC Educational Resources Information Center

    Ybrandt, Helene

    2010-01-01

    The aim of the study was to examine risk and vulnerability factors contributing to problems with alcohol use in adolescence. Data relating to seven life areas (medical status, school status, social relationships, family background and relationships, psychological functioning, legal involvement, and alcohol use) was gathered using the ADAD…

  3. Concurrent Mental Health and Substance Use Problems among Street-Involved Youth

    ERIC Educational Resources Information Center

    Kirst, Maritt; Frederick, Tyler; Erickson, Patricia G.

    2011-01-01

    Among marginalized populations, homeless adults are known to have elevated rates of mental health and substance use problems compared to the general population, but less is known about their youthful homeless counterparts. While few studies currently exist, what research has been conducted among street-involved youth has confirmed high rates of…

  4. Suicidal Ideation among Adolescent School Children, Involvement in Bully-Victim Problems, and Perceived Social Support.

    ERIC Educational Resources Information Center

    Rigby, Ken; Slee, Phillip

    1999-01-01

    Results of self-reports and peer nomination procedures to identify bullies and victims indicated that involvement in bully-victim problems at school, especially for students with relatively little social support, was significantly related to degree of suicidal ideation. (Author/JDM)

  5. A sampling problem in molecular dynamics simulations of macromolecules.

    PubMed Central

    Clarage, J B; Romo, T; Andrews, B K; Pettitt, B M; Phillips, G N

    1995-01-01

    Correlations in low-frequency atomic displacements predicted by molecular dynamics simulations on the order of 1 ns are undersampled for the time scales currently accessible by the technique. This is shown with three different representations of the fluctuations in a macromolecule: the reciprocal space of crystallography using diffuse x-ray scattering data, real three-dimensional Cartesian space using covariance matrices of the atomic displacements, and the 3N-dimensional configuration space of the protein using dimensionally reduced projections to visualize the extent to which phase space is sampled. Images Fig. 1 Fig. 2 Fig. 3 PMID:7724554

  6. NASTRAN thermal analyzer: Theory and application including a guide to modeling engineering problems, volume 2. [sample problem library guide

    NASA Technical Reports Server (NTRS)

    Jackson, C. E., Jr.

    1977-01-01

    A sample problem library containing 20 problems covering most facets of Nastran Thermal Analyzer modeling is presented. Areas discussed include radiative interchange, arbitrary nonlinear loads, transient temperature and steady-state structural plots, temperature-dependent conductivities, simulated multi-layer insulation, and constraint techniques. The use of the major control options and important DMAP alters is demonstrated.

  7. Maternal Depressive Symptoms and Child Behavior Problems among Latina Adolescent Mothers: The Buffering Effect of Mother-reported Partner Child Care Involvement

    PubMed Central

    Smith, Erin N.; Grau, Josefina M.; Duran, Petra A.; Castellanos, Patricia

    2013-01-01

    We examined the relations between maternal depressive symptoms and child internalizing and externalizing problems in a sample of 125 adolescent Latina mothers (primarily Puerto Rican) and their toddlers. We also tested the influence of mother-reported partner child care involvement on child behavior problems and explored mother-reported partner characteristics that related to this involvement. Results suggested that maternal depressive symptoms related to child internalizing and externalizing problems when accounting for contextual risk factors. Importantly, these symptoms mediated the link between life stress and child behavior problems. Mother-reported partner child care interacted with maternal depressive symptoms for internalizing, not externalizing, problems. Specifically, depressive symptoms related less strongly to internalizing problems at higher levels of partner child care than at lower levels. Participants with younger partners, co-residing partners, and in longer romantic relationships reported higher partner child care involvement. Results are discussed considering implications for future research and interventions for mothers, their children, and their partners. PMID:24339474

  8. Progressive Elaboration and Cross-Validation of a Latent Class Typology of Adolescent Alcohol Involvement in a National Sample

    PubMed Central

    Donovan, John E.; Chung, Tammy

    2015-01-01

    Objective: Most studies of adolescent drinking focus on single alcohol use behaviors (e.g., high-volume drinking, drunkenness) and ignore the patterning of adolescents’ involvement across multiple alcohol behaviors. The present latent class analyses (LCAs) examined a procedure for empirically determining multiple cut points on the alcohol use behaviors in order to establish a typology of adolescent alcohol involvement. Method: LCA was carried out on six alcohol use behavior indicators collected from 6,504 7th through 12th graders who participated in Wave I of the National Longitudinal Study of Adolescent Health (AddHealth). To move beyond dichotomous indicators, a “progressive elaboration” strategy was used, starting with six dichotomous indicators and then evaluating a series of models testing additional cut points on the ordinal indicators at progressively higher points for one indicator at a time. Analyses were performed on one random half-sample, and confirmatory LCAs were performed on the second random half-sample and in the Wave II data. Results: The final model consisted of four latent classes (never or non–current drinkers, low-intake drinkers, non–problem drinkers, and problem drinkers). Confirmatory LCAs in the second random half-sample from Wave I and in Wave II support this four-class solution. The means on the four latent classes were also generally ordered on an array of measures reflecting psychosocial risk for problem behavior. Conclusions: These analyses suggest that there may be four different classes or types of alcohol involvement among adolescents, and, more importantly, they illustrate the utility of the progressive elaboration strategy for moving beyond dichotomous indicators in latent class models. PMID:25978828

  9. A phenomenographic analysis of first-year engineering students' experiences with problems involving multiple possible solutions

    NASA Astrophysics Data System (ADS)

    Dringenberg, Emily A.

    Engineers are expected to solve problems that are ill-structured. These problems are presented with a lack of necessary information and allow for different ways of engaging with the problem; they are open-ended and involve multiple possible solutions with multiple means of evaluation. In order to allow maximum time for students to develop skills for solving such problems, undergraduate engineering programs can introduce such problems during the first year of students' education, in the form of cornerstone design tasks. This provides students with more opportunities to develop their ability to engage with ill-structured problems, which are characteristic of engineering work. Researchers have documented variation within both the behavior and perceptions of students' early experiences with design problems. General themes include novice-like design behavior, discomfort with lack of information, difficulty with problem scoping, and resistance to ambiguity. To build on these generalizations of students' experiences, a more thorough understanding of the variation in how students experience this phenomenon of engaging with ill-structured problems is needed to design effective learning environments. This work presents the qualitatively different ways that engineering students experience problems with multiple possible solutions during their first year of engineering studies. Using phenomenography as the methodological framework, data were collected through in-depth, semi-structured interviews with 27 first-year engineering students. The iterative, phenomenographic analysis resulted in seven descriptive categories for the ways participants experienced problems involving multiple possible solutions. The names of these categories represent the different foci of the students' experiences: completion, transition, iteration, organization, collaboration, reasoning, and growth. These categories are organized along two crucial dimensions of variation: reaction to ambiguity and role

  10. A social marketing approach to involving Afghans in community-level alcohol problem prevention.

    PubMed

    Cherry, L; Redmond, S P

    1994-06-01

    A program for preventing alcohol-related problems at the community level using environmentally-focused, public health approaches sought to involve a new segment of the community. That segment consisted of recently-immigrated Afghans from a traditionally abstinent culture. Social marketing research was employed to elicit value-based benefits to be used in promoting the product (involvement with environmental change efforts) to the target audience. While the channels of distribution for promotional messages were easily identified, special attention was required relative to effective spokespersons. Much was also learned about the immigration experience of Afghans in a San Francisco Bay Area community that has significance for other fields. PMID:24258928

  11. Hybrid transfinite element modeling/analysis of nonlinear heat conduction problems involving phase change

    NASA Technical Reports Server (NTRS)

    Tamma, Kumar K.; Railkar, Sudhir B.

    1988-01-01

    The present paper describes the applicability of hybrid transfinite element modeling/analysis formulations for nonlinear heat conduction problems involving phase change. The methodology is based on application of transform approaches and classical Galerkin schemes with finite element formulations to maintain the modeling versatility and numerical features for computational analysis. In addition, in conjunction with the above, the effects due to latent heat are modeled using enthalpy formulations to enable a physically realistic approximation to be dealt computationally for materials exhibiting phase change within a narrow band of temperatures. Pertinent details of the approach and computational scheme adapted are described in technical detail. Numerical test cases of comparative nature are presented to demonstrate the applicability of the proposed formulations for numerical modeling/analysis of nonlinear heat conduction problems involving phase change.

  12. Using orthogonal array sampling to cope with uncertainty in ground water problems.

    PubMed

    Baalousha, Husam

    2009-01-01

    Uncertainty in ground water hydrology originates from different sources. Neglecting uncertainty in ground water problems can lead to incorrect results and misleading output. Several approaches have been developed to cope with uncertainty in ground water problems. The most widely used methods in uncertainty analysis are Monte Carlo simulation (MCS) and Latin hypercube sampling (LHS), developed from MCS. Despite the simplicity of MCS, many runs are required to achieve a reliable result. This paper presents orthogonal array (OA) sampling as a means to cope with uncertainty in ground water problems. The method was applied to an analytical stream depletion problem. To examine the convergence rate of the OA sampling, the results were compared to MCS and LHS. This study shows that OA can be applied to ground water problems. Results reveal that the convergence rate of the OA sampling is faster than MCS and LHS, with a smaller error of estimate when applied to a stream depletion problem. PMID:19735309

  13. Influences of behavior and academic problems at school entry on marijuana use transitions during adolescence in an African American sample

    PubMed Central

    Reboussin, Beth A.; Ialongo, Nicholas S.; Green, Kerry M.

    2014-01-01

    Background: The aim of this study was to examine how patterns of academic and behavior problems in first grade relate to longitudinal transitions in marijuana use from middle school through entry into high school among African Americans. Methods: Latent class and latent transition analyses were conducted on a community sample of 458 low-income, urban-dwelling African-Americans. Results: Two behavior problem classes emerged at school entry; externalizing and attention/concentration. Academic problems co-occurred with both problem behavior classes although more strongly with attention/concentration. Youth in the attention/ concentration problem class were more likely to transition from no marijuana involvement to use and problems beginning in 7th grade and to use and problems given the opportunity to use marijuana early in high school compared to youth with no problems. Youth in the externalizing behavior problem class were significantly more likely to transition from no involvement to having a marijuana opportunity during the transition to high school compared to youth in the attention/concentration problems class. Conclusions: These findings highlight the importance of developing prevention programs and providing school services that address the co-occurrence of academic and behavior problems, as well as their subtype specific risks for marijuana involvement, particularly for low-income minority youth who may be entering school less ready than their non-minority peers. These findings also provide evidence for a need to continue to deliver interventions in middle and high school focused on factors that may protect youth during these critical transition periods when they may be especially vulnerable to opportunities to use marijuana based on their academic and behavioral risk profile. PMID:25305658

  14. 12-Step involvement among a U.S. national sample of Oxford House residents

    PubMed Central

    Majer, John M.; Jason, Leonard A.; Ferrari, Joseph R.; Miller, Steve A.

    2011-01-01

    A longitudinal analysis was conducted among a U.S. national sample of persons affiliated with Alcoholics Anonymous and Narcotics Anonymous living in self-run recovery homes (Oxford Houses). Categorical involvement in a set of 12-step activities (i.e., having a sponsor, reading 12-step literature, doing service work, and calling other members for help) and averaged summary scores of involvement were examined in relation to abstinence and self-efficacy for abstinence. Participants who were categorically involved in all 12-step activities reported significantly higher levels of abstinence and self-efficacy for abstinence at 1 year compared with those who were less involved, whereas averaged summary scores of involvement were not a significant predictor of abstinence. Participants’ number of days in Oxford Houses, but not rates of 12-step meeting attendance, was significantly related to increased abstinence. Findings suggest that categorical involvement in a number of 12-step activities equip persons with substance use disorders with resources for ongoing recovery. PMID:21353447

  15. "Good samples make good assays" – the problem of sourcing clinical samples for a standardization project.

    PubMed

    Van Houcke, Sofie K; Thienpont, Linda M

    2013-05-01

    Clinical samples are the cornerstone in all aspects related to in vitro diagnostic testing. They are particularly valuable in the process of establishing/validating metrological traceability, because they eliminate commutability issues potentially associated with artificial calibrators. Therefore, they are essential for IFCC standardization projects. However, sourcing clinical specimens is particularly challenging. It mostly turns out that only dedicated supply sources can accommodate the varying specifications within reasonable timelines. Here we describe the torturous experience in this regard of the IFCC Working Group for Standardization of Thyroid Function tests (since transformed into a Committee). We always focused on obtaining high quality samples in sufficient volume to serve all project participants. We applied a step-up approach: in phase I, we used high volume (200 mL of plasma/serum) single donations from apparently healthy individuals, and switched in phase II and III to medium-sized volume clinical samples (15 – 30 mL) from well-defined patient categories. In the first two phases we observed for some assays a sample-related discrepant analytical performance for total/free triiodothyronine and thyroid stimulating hormone (TSH), whereas in phase III we faced a severe delay in obtaining the relevant panels for free thyroxine (FT4) and TSH (n = 90 and n = 100, respectively). Additional experiments only allowed us to exclude hypothesized causes of the observations. We believe that there would be merit in a collaborative effort by chairholders of similar projects to establish a sample procurement infrastructure based on a solid relationship with commercial supply sources with the support of a significant number of committed clinicians. PMID:23045383

  16. Short-term Trajectories of Substance Use in a sample of Drug-involved Probationers

    PubMed Central

    Caudy, Michael S.; Tang, Liansheng; Wooditch, Alese; Taxman, Faye S.

    2013-01-01

    The current study estimates trajectories of illegal substance use in a sample of 251 drug-involved probationers to identify risk profiles that predict group membership and explores the impact of treatment participation across these trajectories. Trajectory analyses reveal five patterns of drug use during probation supervision. Age and the use of hard drugs are identified as the strongest predictors of involvement in illicit drug use while on probation. The effect of participation in substance use treatment varies across treatment settings and trajectory groups. Prior research has tended to treat drug abusers as a homogeneous population, but the current study findings suggest considerable heterogeneity amongst drug users involved in the criminal justice system. Identifying trajectories of drug use during supervision can help identify individuals who may be more likely to persist in drug use, can inform practice by identifying individuals in need of more intensive treatment services, and can assist in developing new drug treatment strategies. PMID:23953166

  17. Patient involvement in problem presentation and diagnosis delivery in primary care.

    PubMed

    Ijäs-Kallio, Taru; Ruusuvuori, Johanna; Peräkylä, Anssi

    2010-01-01

    This article reports a conversation analytic study of primary care physicians' orientations to different types of patients' problem presentation. Four types of problem presentation are examined: 1. symptoms only; 2. candidate diagnosis; 3. diagnosis implicative symptom description; and 4. candidate diagnosis as background information. The analysis shows that both in receiving the problem presentation at the beginning of the visit and in delivering a diagnosis later on, doctors address the patients' presentations which involved or implied a candidate diagnosis. In contrast, following a symptoms-only type of problem presentation such references predominantly are not made. The study suggests that patients' problem presentation have a crucial role in shaping the doctor's communication patterns also in the phases of consultation in which the patient's active participation is of lesser significance, such as the diagnostic phase. The findings are discussed in relation to the question of patient participation in the medical consultation. The data consist of 86 video-recorded Finnish primary care consultations for upper respiratory tract infection including both child and adult patients. PMID:22049636

  18. Father involvement moderates the effect of maternal depression during a child's infancy on child behavior problems in kindergarten.

    PubMed

    Mezulis, Amy H; Hyde, Janet Shibley; Clark, Roseanne

    2004-12-01

    This research investigated whether father involvement in infancy may reduce or exacerbate the well-established adverse effect of maternal depression during a child's infancy on behavior problems in childhood. In a community sample (N = 350), the authors found that fathers' self-reported parenting styles interacted with the amount of time fathers spent caring for their infants to moderate the longitudinal effect of maternal depression during the child's infancy on children's internalizing, but not externalizing, behaviors. Low to medium amounts of high-warmth father involvement and high amounts of medium- or high-control father involvement at this time were associated with lower child internalizing behaviors. Paternal depression during a child's infancy exacerbated the effect of maternal depression, but this moderating effect was limited to depressed fathers spending medium to high amounts of time caring for their infants. Results emphasize the moderating role fathers may play in reducing or exacerbating the adverse long-term effects of maternal depression during a child's infancy on later child behavior problems. PMID:15598163

  19. Greater involvement and diversity of Internet gambling as a risk factor for problem gambling

    PubMed Central

    Russell, Alex; Blaszczynski, Alex; Hing, Nerilee

    2015-01-01

    Background: Concerns that Internet gambling has elevated the prevalence of problem gambling have not been substantiated; however, evidence suggests a subgroup of Internet gamblers do experience higher rates of gambling harms. Greater overall involvement in gambling appears to be predictive of harms. The purpose of this study was to examine differences between Internet gamblers with a single or multiple online gambling accounts, including their gambling behaviours, factors influencing their online gambling and risk of experiencing gambling problems. Methods: Internet gamblers (3178) responding to an online survey that assessed their gambling behaviour, and use of single or multiple online gambling accounts. Results: Results revealed that multiple account holders were more involved gamblers, gambling on more activities and more frequently, and had higher rates of gambling problems than single account holders. Multiple account holders selected gambling sites based on price, betting options, payout rates and game experience, whereas single account holders prioritized legality and consumer protection features. Conclusion: Results suggest two different types of Internet gamblers: one motivated to move between sites to optimize preferred experiences with a tendency to gamble in a more volatile manner; and a smaller, but more stable group less influenced by promotions and experiences, and seeking a reputable and safe gambling experience. As the majority of Internet gamblers use multiple accounts, more universal responsible gambling strategies are needed to assist gamblers to track and control their expenditure to reduce risks of harm. PMID:25745873

  20. Parabolic equation solution of seismo-acoustics problems involving variations in bathymetry and sediment thickness.

    PubMed

    Collis, Jon M; Siegmann, William L; Jensen, Finn B; Zampolli, Mario; Küsel, Elizabeth T; Collins, Michael D

    2008-01-01

    Recent improvements in the parabolic equation method are combined to extend this approach to a larger class of seismo-acoustics problems. The variable rotated parabolic equation [J. Acoust. Soc. Am. 120, 3534-3538 (2006)] handles a sloping fluid-solid interface at the ocean bottom. The single-scattering solution [J. Acoust. Soc. Am. 121, 808-813 (2007)] handles range dependence within elastic sediment layers. When these methods are implemented together, the parabolic equation method can be applied to problems involving variations in bathymetry and the thickness of sediment layers. The accuracy of the approach is demonstrated by comparing with finite-element solutions. The approach is applied to a complex scenario in a realistic environment. PMID:18177137

  1. On Sensitivity Reduction Problems of Sampled-Data Systems: Relationships to the Problems of Discrete-Time Systems

    NASA Astrophysics Data System (ADS)

    Ito, Yoshimichi; Shirahama, Hiroshi; Hagiwara, Tomomichi

    This paper is concerned with the sensitivity reduction (SR) and complementary sensitivity reduction (CSR) problems of sampled-data systems. We begin our study by showing that, given a sampled-data system Σ, the H∞ norms of the sensitivity and complementary sensitivity of Σ can be expressed as those for an equivalent discrete-time system Σ called the doubly sensitivity-preserving discretized system. We also consider the conventional ‘hold equivalent’ discretized system Σd, which has generally been believed, due to the ignoring of the intersample behavior, to be irrelevant to the SR/CSR problems of Σ (and thus Σ). We then establish that there in fact exists an important relation between the seemingly completely irrelevant discrete-time systems Σ and Σd. More precisely, we show through the coprime factorization approach about Σ and Σd that the CSR problem of Σ (and thus Σ) is equivalent to a weighted CSR problem of Σd and that the SR problem of Σ is equivalent to a weighted mixed sensitivity reduction problem of Σd. In particular, we show that the frequency-dependent weights that arise in this interplay between Σ and Σd can be described with an important function called the aliasing factor ψ, and further clarify an important analytic property of ψ. We then demonstrate that this property of ψ can be used to prove some relation between the best achievable performance in the SR (respectively, CSR) problem of Σ (and thus Σ) and that of Σd. An interesting property between the SR problem and CSR problem of Σ is also provided.

  2. Near-optimal, asymptotic tracking in control problems involving state-variable inequality constraints

    NASA Technical Reports Server (NTRS)

    Markopoulos, N.; Calise, A. J.

    1993-01-01

    The class of all piecewise time-continuous controllers tracking a given hypersurface in the state space of a dynamical system can be split by the present transformation technique into two disjoint classes; while the first of these contains all controllers which track the hypersurface in finite time, the second contains all controllers that track the hypersurface asymptotically. On this basis, a reformulation is presented for optimal control problems involving state-variable inequality constraints. If the state constraint is regarded as 'soft', there may exist controllers which are asymptotic, two-sided, and able to yield the optimal value of the performance index.

  3. Problem Gambling and the Youth-to-Adulthood Transition: Assessing Problem Gambling Severity Trajectories in a Sample of Young Adults.

    PubMed

    Edgerton, Jason D; Melnyk, Timothy S; Roberts, Lance W

    2015-12-01

    In this study, using four wave longitudinal data, we examined problem gambling severity trajectories in a sample of young adults. Using latent growth curve modeling, we examined how initial level of problem gambling severity and the rate of change were affected by 11 time-invariant predictors: gender, age of onset of gambling, experiencing a big win early in gambling career, experiencing a big loss early in gambling career, alcohol dependence, drug dependence, anxiety, depression, perceived social support, illusion of control, and impulsiveness. Five of the eleven predictors affected initial levels of problem gambling severity; however only impulsiveness affected the rate of change across time. The mean trajectory was negative (lessening of problem gambling risk severity across time), but there was significant inter-individual variation in trajectories and initial levels of problem gambling severity. The main finding of problem gambling risk diminishing over time challenges the conventional picture of problem gambling as an inevitable "downward spiral," at least among young adults, and suggests that targeted prevention campaigns may be a cost-effective alternative for reaching treatment resistant youth. PMID:25260900

  4. [The Problems of Vertical Mode Steam Sterilizers Found in National Supervision Sampling].

    PubMed

    Wang, Bo; Yang, Yan

    2015-11-01

    This article statistically analyzes and discusses the problems in national supervision sampling of vertical mode steam sterilizers in 2014. For improving product quality, strengthening the supervision and management, it provides a reference. PMID:27066692

  5. TOPAZ - the transient one-dimensional pipe flow analyzer: code validation and sample problems

    SciTech Connect

    Winters, W.S.

    1985-10-01

    TOPAZ is a ''user friendly'' computer code for modeling the one-dimensional-transient physics of multi-species gas transfer in arbitrary arrangements of pipes, valves, vessels, and flow branches. This document presents a series of sample problems designed to aid potential users in creating TOPAZ input files. To the extent possible, sample problems were selected for which analytical solutions currently exist. TOPAZ comparisons with such solutions are intended to provide a measure of code validation.

  6. The Prevalence and Incremental Validity of Identity Problem Symptoms in a High School Sample

    ERIC Educational Resources Information Center

    Berman, Steven L.; Weems, Carl F.; Petkus, Veronica F.

    2009-01-01

    This paper examines the expression, prevalence, and incremental validity of identity problem symptoms in adolescence. A sample of high school students (N = 140) aged 15-18 completed measures of identity problem symptoms, identity status, and psychological symptom severity. Findings suggested that 14.3% would meet DSM IV criteria for identity…

  7. Parent-Reported Feeding and Feeding Problems in a Sample of Dutch Toddlers

    ERIC Educational Resources Information Center

    de Moor, Jan; Didden, Robert; Korzilius, Hubert

    2007-01-01

    Little is known about the feeding behaviors and problems with feeding in toddlers. In the present questionnaire study, data were collected on the feeding behaviors and feeding problems in a relatively large (n = 422) sample of Dutch healthy toddlers (i.e. 18-36 months old) who lived at home with their parents. Results show that three meals a day…

  8. A Model for Predicting Behavioural Sleep Problems in a Random Sample of Australian Pre-Schoolers

    ERIC Educational Resources Information Center

    Hall, Wendy A.; Zubrick, Stephen R.; Silburn, Sven R.; Parsons, Deborah E.; Kurinczuk, Jennifer J.

    2007-01-01

    Behavioural sleep problems (childhood insomnias) can cause distress for both parents and children. This paper reports a model describing predictors of high sleep problem scores in a representative population-based random sample survey of non-Aboriginal singleton children born in 1995 and 1996 (1085 girls and 1129 boys) in Western Australia.…

  9. Trace Chlorinated Organics Analysis in Highly Radioactive Samples-Problems and Solutions

    SciTech Connect

    Macek, P.; Hawthorne, L.; Hass, J. R.; Harvan, D.

    2002-02-26

    This paper discusses some of the problems that are associated with the analysis of highly radioactive samples for chlorinated organic compounds at the part per trillion level. To date, both high fission product activity and transuranic activity have been handle successfully. Communication issues, sample handling, transfer between laboratories and analytical challenges are discussed.

  10. Exact image method for Gaussian beam problems involving a planar interface

    NASA Technical Reports Server (NTRS)

    Lindell, I. V.

    1987-01-01

    Exact image method, recently introduced for the solution of electromagnetic field problems involving sources above a planar interface or two homogeneous media, is shown to be valid also for sources located in complex space, which makes its application possible for Gaussian beam analysis. It is demonstrated that the Goos-Hanchen shift and the angular shift of a TE polarized beam are correctly given as asymptotic results by the exact reflection image theory. Also, the apparent image location giving the correct Gaussian beam transmitted through the interface is obtained as another asymptotic check. The present theory makes it possible to calculate the exact coupling from the Gaussian beam to the reflected and refracted beams, as well as to the surface wave.

  11. Hybrid nested sampling algorithm for Bayesian model selection applied to inverse subsurface flow problems

    SciTech Connect

    Elsheikh, Ahmed H.; Wheeler, Mary F.; Hoteit, Ibrahim

    2014-02-01

    A Hybrid Nested Sampling (HNS) algorithm is proposed for efficient Bayesian model calibration and prior model selection. The proposed algorithm combines, Nested Sampling (NS) algorithm, Hybrid Monte Carlo (HMC) sampling and gradient estimation using Stochastic Ensemble Method (SEM). NS is an efficient sampling algorithm that can be used for Bayesian calibration and estimating the Bayesian evidence for prior model selection. Nested sampling has the advantage of computational feasibility. Within the nested sampling algorithm, a constrained sampling step is performed. For this step, we utilize HMC to reduce the correlation between successive sampled states. HMC relies on the gradient of the logarithm of the posterior distribution, which we estimate using a stochastic ensemble method based on an ensemble of directional derivatives. SEM only requires forward model runs and the simulator is then used as a black box and no adjoint code is needed. The developed HNS algorithm is successfully applied for Bayesian calibration and prior model selection of several nonlinear subsurface flow problems.

  12. Digital image correlation involves an inverse problem: A regularization scheme based on subset size constraint

    NASA Astrophysics Data System (ADS)

    Zhan, Qin; Yuan, Yuan; Fan, Xiangtao; Huang, Jianyong; Xiong, Chunyang; Yuan, Fan

    2016-06-01

    Digital image correlation (DIC) is essentially implicated in a class of inverse problem. Here, a regularization scheme is developed for the subset-based DIC technique to effectively inhibit potential ill-posedness that likely arises in actual deformation calculations and hence enhance numerical stability, accuracy and precision of correlation measurement. With the aid of a parameterized two-dimensional Butterworth window, a regularized subpixel registration strategy is established, in which the amount of speckle information introduced to correlation calculations may be weighted through equivalent subset size constraint. The optimal regularization parameter associated with each individual sampling point is determined in a self-adaptive way by numerically investigating the curve of 2-norm condition number of coefficient matrix versus the corresponding equivalent subset size, based on which the regularized solution can eventually be obtained. Numerical results deriving from both synthetic speckle images and actual experimental images demonstrate the feasibility and effectiveness of the set of newly-proposed regularized DIC algorithms.

  13. A hybrid computer program for rapidly solving flowing or static chemical kinetic problems involving many chemical species

    NASA Technical Reports Server (NTRS)

    Mclain, A. G.; Rao, C. S. R.

    1976-01-01

    A hybrid chemical kinetic computer program was assembled which provides a rapid solution to problems involving flowing or static, chemically reacting, gas mixtures. The computer program uses existing subroutines for problem setup, initialization, and preliminary calculations and incorporates a stiff ordinary differential equation solution technique. A number of check cases were recomputed with the hybrid program and the results were almost identical to those previously obtained. The computational time saving was demonstrated with a propane-oxygen-argon shock tube combustion problem involving 31 chemical species and 64 reactions. Information is presented to enable potential users to prepare an input data deck for the calculation of a problem.

  14. Efficient Bayesian parameter estimation with implicit sampling and surrogate modeling for a vadose zone hydrological problem

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Pau, G. S. H.; Finsterle, S.

    2015-12-01

    Parameter inversion involves inferring the model parameter values based on sparse observations of some observables. To infer the posterior probability distributions of the parameters, Markov chain Monte Carlo (MCMC) methods are typically used. However, the large number of forward simulations needed and limited computational resources limit the complexity of the hydrological model we can use in these methods. In view of this, we studied the implicit sampling (IS) method, an efficient importance sampling technique that generates samples in the high-probability region of the posterior distribution and thus reduces the number of forward simulations that we need to run. For a pilot-point inversion of a heterogeneous permeability field based on a synthetic ponded infiltration experiment simu­lated with TOUGH2 (a subsurface modeling code), we showed that IS with linear map provides an accurate Bayesian description of the parameterized permeability field at the pilot points with just approximately 500 forward simulations. We further studied the use of surrogate models to improve the computational efficiency of parameter inversion. We implemented two reduced-order models (ROMs) for the TOUGH2 forward model. One is based on polynomial chaos expansion (PCE), of which the coefficients are obtained using the sparse Bayesian learning technique to mitigate the "curse of dimensionality" of the PCE terms. The other model is Gaussian process regression (GPR) for which different covariance, likelihood and inference models are considered. Preliminary results indicate that ROMs constructed based on the prior parameter space perform poorly. It is thus impractical to replace this hydrological model by a ROM directly in a MCMC method. However, the IS method can work with a ROM constructed for parameters in the close vicinity of the maximum a posteriori probability (MAP) estimate. We will discuss the accuracy and computational efficiency of using ROMs in the implicit sampling procedure

  15. Comparing Problem Gamblers with Moderate-Risk Gamblers in a Sample of University Students

    PubMed Central

    Shen, Yi; Kairouz, Sylvia; Nadeau, Louise; Robillard, Chantal

    2015-01-01

    Background and Aims In an effort to provide further empirical evidence of meaningful differences, this study explores, in a student population, the distinctions in gambling behavioral patterns and specific associated problems of two levels of gambling severity by comparing problem gamblers (PG) and moderate-risk gamblers (MR) as defined by the score on the Problem Gambling Severity Index (PGSI; MR: 3-7; PG: 8 and more). Methods The study sample included 2,139 undergraduate students (male = 800, mean age = 22.6) who completed the PGSI and questionnaires on associated problems. Results Results show that problem gamblers engage massively and more diversely in gambling activities, more often and in a greater variety of locations, than moderate-risk gamblers. In addition, important differences have been observed between moderate-risk and problem gamblers in terms of expenditures and accumulated debt. In regards to the associated problems, compared to moderate-risk gamblers, problem gamblers had an increased reported psychological distress, daily smoking, and possible alcohol dependence. Discussion and Conclusions The severity of gambling and associated problems found in problem gamblers is significantly different from moderate-risk gamblers, when examined in a student population, to reiterate caution against the amalgamation of these groups in future research. PMID:26014673

  16. Work Involvement and Timing of Motherhood in the Accumulation of Problems in Social Functioning in Young Women.

    ERIC Educational Resources Information Center

    Ronka, Anna; Pulkkinen, Lea

    1998-01-01

    Examined longitudinally the relationship between earlier risk factors and later problems in young Finnish women's social functioning. Found that low work involvement mediated between risk factors and accumulation of problems in social functioning in young adulthood. Risk factors increased the likelihood of early motherhood, but early motherhood…

  17. Energy and the Confused Student V: The Energy/Momentum Approach to Problems Involving Rotating and Deformable Systems

    ERIC Educational Resources Information Center

    Jewett, John W., Jr.

    2008-01-01

    Energy is a critical concept in physics problem-solving, but is often a major source of confusion for students if the presentation is not carefully crafted by the instructor or the textbook. A common approach to problems involving deformable or rotating systems that has been discussed in the literature is to employ the work-kinetic energy theorem…

  18. Acceleration of multiple solution of a boundary value problem involving a linear algebraic system

    NASA Astrophysics Data System (ADS)

    Gazizov, Talgat R.; Kuksenko, Sergey P.; Surovtsev, Roman S.

    2016-06-01

    Multiple solution of a boundary value problem that involves a linear algebraic system is considered. New approach to acceleration of the solution is proposed. The approach uses the structure of the linear system matrix. Particularly, location of entries in the right columns and low rows of the matrix, which undergo variation due to the computing in the range of parameters, is used to apply block LU decomposition. Application of the approach is considered on the example of multiple computing of the capacitance matrix by method of moments used in numerical electromagnetics. Expressions for analytic estimation of the acceleration are presented. Results of the numerical experiments for solution of 100 linear systems with matrix orders of 1000, 2000, 3000 and different relations of variated and constant entries of the matrix show that block LU decomposition can be effective for multiple solution of linear systems. The speed up compared to pointwise LU factorization increases (up to 15) for larger number and order of considered systems with lower number of variated entries.

  19. Caregiver Reports of Sleep Problems on a Convenience Sample of Children with Fragile X Syndrome

    ERIC Educational Resources Information Center

    Kronk, Rebecca; Dahl, Ronald; Noll, Robert

    2009-01-01

    Caregivers reported on sleep in a convenience sample of 90 children with fragile X syndrome utilizing a standardized assessment tool, the Children's Sleep Habits Questionnaire (CSHQ), and a 14-day sleep diary. CSHQ data indicated that 47% of participants had sleep problems at a level that suggested referral and further evaluation. Sleep diary data…

  20. The Structure of Problem Behavior in a Sample of Maltreated Youths

    ERIC Educational Resources Information Center

    Culhane, Sara E.; Taussig, Heather N.

    2009-01-01

    Studies of adolescent community samples suggest that substance use, risky sexual behavior, delinquency, and other problem behaviors can be explained in part by a single, underlying factor or syndrome. Of current interest is the generalizability of these findings to subgroups or special populations of youths who may be at high risk for problem…

  1. Involvement in Intimate Partner Psychological Abuse and Suicide Proneness in College Women: Alcohol Related Problems as a Potential Mediator

    PubMed Central

    Lamis, Dorian A.; Malone, Patrick S.; Langhinrichsen-Rohling, Jennifer

    2010-01-01

    This study examined the relations among involvement in intimate partner psychological abuse, alcohol-related problems, and suicide proneness as measured by the Life Attitudes Schedule – Short Form (LAS-SF) in college women (N = 709). Results revealed that, as expected, being involved in a psychologically abusive relationship was significantly and positively correlated with alcohol-related problems and alcohol-related problems were significantly and positively correlated with suicide proneness. Additionally, the intimate partner psychological abuse involvement-suicide proneness link was significantly mediated by alcohol-related problems. Implications are offered for the improved identification and treatment of young women at risk for suicidal and health-diminishing behaviors. PMID:20544000

  2. Family Background, Parental Involvement, and Parent Child Interactions as Predictors of Fifth-Graders Behavior Problems

    ERIC Educational Resources Information Center

    Brown, Tamala P.

    2012-01-01

    Many studies have been conducted to address childhood behavior problems, but much remains unknown regarding the causes and factors that affect internalizing and externalizing problems in children. The purpose of the current research study was to examine the relationships between children's internalizing and externalizing behavior problems and (a)…

  3. Extremality Conditions and Regularity of Solutions to Optimal Partition Problems Involving Laplacian Eigenvalues

    NASA Astrophysics Data System (ADS)

    Ramos, Miguel; Tavares, Hugo; Terracini, Susanna

    2016-04-01

    Let {Ω subset {R}^N} be an open bounded domain and {m in {N}}. Given {k_1,ldots,k_m in {N}}, we consider a wide class of optimal partition problems involving Dirichlet eigenvalues of elliptic operators, of the following form inf{F({λ_{k1}}(ω_1),ldots,λ_{k_m}(ω_m)): (ω_1,ldots, ω_m) in {P}_m(Ω)}, where {λ_{k_i}(ω_i)} denotes the k i -th eigenvalue of {(-Δ,H10(ω_i))} counting multiplicities, and {{P}_m(Ω)} is the set of all open partitions of {Ω}, namely {P}_m(Ω)={(ω_1, ldots, ω_m):ω_i subset Ω open, ωi \\capω_j=emptyset forall i ≠ j }. While the existence of a quasi-open optimal partition {(ω_1,ldots, ω_m)} follows from a general result by Bucur, Buttazzo and Henrot [Adv Math Sci Appl 8(2):571-579, 1998], the aim of this paper is to associate with such minimal partitions and their eigenfunctions some suitable extremality conditions and to exploit them, proving as well the Lipschitz continuity of some eigenfunctions, and the regularity of the partition in the sense that the free boundary {\\cup_{i=1}^m partial ωi \\cap Ω} is, up to a residual set, locally a {C^{1,α}} hypersurface. This last result extends the ones in the paper by Caffarelli and Lin [J Sci Comput 31(1-2):5-18, 2007] to the case of higher eigenvalues.

  4. Overcoming the Rare Event Sampling Problem in Biological Systems with Infinite Swapping.

    PubMed

    Plattner, Nuria; Doll, J D; Meuwly, Markus

    2013-09-10

    Infinite swapping (INS) is a recently developed method to address the rare event sampling problem. For INS, an expanded computational ensemble composed of a number of replicas at different temperatures is used, similar to the widely used parallel tempering (PT) method. While the basic concept of PT is to sample various replicas of the system at different temperatures and exchange information between the replicas occasionally, INS uses the symmetrized distribution of configurations in temperature space, which corresponds to the infinite swapping limit of PT. The effect of this symmetrization and the enhanced information exchange between replicas is evaluated for three different biological systems representing different sampling problems in biology: (1) blocked alanine dipeptide, which is a small system and therefore optimal to evaluate sampling efficiency quantitatively, (2) Villin headpiece, which is used as a test case for the protein folding process, and (3) neuroglobin, which is used to evaluate the effects of enhanced information exchange between replicas for sampling the substate space of a folded protein. For these three test systems, PINS is compared to PT, and it is found that in all cases the sampling with PINS is substantially more efficient. PMID:26592410

  5. Prevalence of problem-related drinking among doctors: a review on representative samples

    PubMed Central

    Rosta, Judith

    2005-01-01

    Aims: This paper is a review of the literature on problem-related drinking of alcohol among medical doctors, and it deals with the epidemiology and results. Methods: A search of computer literature databases - PubMed and ETOH - was performed to locate articles reporting problem-related drinking among doctors, using population-based samples of doctors within the last two decades. Results: In the light of different definitions of problem-related drinking, there was found a breadth of prevalence of problem-related drinking - from heavy drinking and hazardous drinking (12%-16%) to misuse and dependence (6%-8%) - within the population-based samples of doctors. An increased risk was positively related to male doctors and doctors of the age of 40-45 years and older, and to some factors of work, lifestyle and health. Conclusion: For the future, it seems necessary to sensitise the research for problem-related drinking of doctors in Germany, e.g. initiating a representative survey, analysing the drinking of alcohol in the context of health, life-style and work-related factors. PMID:19675724

  6. A HUPO test sample study reveals common problems in mass spectrometry-based proteomics.

    PubMed

    Bell, Alexander W; Deutsch, Eric W; Au, Catherine E; Kearney, Robert E; Beavis, Ron; Sechi, Salvatore; Nilsson, Tommy; Bergeron, John J M

    2009-06-01

    We performed a test sample study to try to identify errors leading to irreproducibility, including incompleteness of peptide sampling, in liquid chromatography-mass spectrometry-based proteomics. We distributed an equimolar test sample, comprising 20 highly purified recombinant human proteins, to 27 laboratories. Each protein contained one or more unique tryptic peptides of 1,250 Da to test for ion selection and sampling in the mass spectrometer. Of the 27 labs, members of only 7 labs initially reported all 20 proteins correctly, and members of only 1 lab reported all tryptic peptides of 1,250 Da. Centralized analysis of the raw data, however, revealed that all 20 proteins and most of the 1,250 Da peptides had been detected in all 27 labs. Our centralized analysis determined missed identifications (false negatives), environmental contamination, database matching and curation of protein identifications as sources of problems. Improved search engines and databases are needed for mass spectrometry-based proteomics. PMID:19448641

  7. Symptoms and problems in a nationally representative sample of advanced cancer patients.

    PubMed

    Johnsen, A T; Petersen, M A; Pedersen, L; Groenvold, M

    2009-09-01

    Little is known about the need for palliative care among advanced cancer patients who are not in specialist palliative care. The purpose was to identify prevalence and predictors of symptoms and problems in a nationally representative sample of Danish advanced cancer patients. Patients with cancer stage 3 or 4 from 54 hospital departments (n = 1630) received the EORTC QLQ-C30 questionnaire. Mean scores were calculated according to the scoring manual and in addition a 'symptom/problem' and a 'severe symptom/problem' was defined and calculated. Multiple logistic regression was used to identify predictors. In total, 977 (60%) patients participated. The most frequent symptoms/problems were fatigue (57%; severe 22%) followed by reduced role function, insomnia and pain. Age, cancer stage, primary tumour, type of department, marital status and whether the patient had recently been hospitalized or not were associated with several symptoms and problems. This is probably the first nationally representative study of its kind. It shows that advanced cancer patients in Denmark have symptoms and problems that deserve attention and that some patient groups are especially at risk. PMID:19443525

  8. A Problem and Its Solution Involving Maxwell's Equations and an Inhomogeneous Medium.

    ERIC Educational Resources Information Center

    Williamson, W., Jr.

    1980-01-01

    Maxwell's equation are solved for an inhomogeneous medium which has a coordinate-dependent dielectric function. The problem and its solutions are given in a format which should make it useful as an intermediate or advanced level problem in an electrodynamics course. (Author/SK)

  9. Infinitely many solutions for differential inclusion problems in {{R}^N} involving the {p(x)}-Laplacian

    NASA Astrophysics Data System (ADS)

    Ge, Bin; Liu, Li-Li

    2016-03-01

    In this paper we consider the differential inclusion problem in {{R}^N} involving the {p(x)}-Laplacian of the type -triangle_{p(x)} u+V(x)|u|^{p(x)-2}uin partial F(x,u) {in} {R}^N. Some new criteria to guarantee that the existence of infinitely many solutions for the considered problem is established by using the genus properties in nonsmooth critical point theory, which extend and complement previously known results in the literature.

  10. Exploring the Connection Between Sampling Problems in Bayesian Inference and Statistical Mechanics

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew

    2006-01-01

    The Bayesian and statistical mechanical communities often share the same objective in their work - estimating and integrating probability distribution functions (pdfs) describing stochastic systems, models or processes. Frequently, these pdfs are complex functions of random variables exhibiting multiple, well separated local minima. Conventional strategies for sampling such pdfs are inefficient, sometimes leading to an apparent non-ergodic behavior. Several recently developed techniques for handling this problem have been successfully applied in statistical mechanics. In the multicanonical and Wang-Landau Monte Carlo (MC) methods, the correct pdfs are recovered from uniform sampling of the parameter space by iteratively establishing proper weighting factors connecting these distributions. Trivial generalizations allow for sampling from any chosen pdf. The closely related transition matrix method relies on estimating transition probabilities between different states. All these methods proved to generate estimates of pdfs with high statistical accuracy. In another MC technique, parallel tempering, several random walks, each corresponding to a different value of a parameter (e.g. "temperature"), are generated and occasionally exchanged using the Metropolis criterion. This method can be considered as a statistically correct version of simulated annealing. An alternative approach is to represent the set of independent variables as a Hamiltonian system. Considerab!e progress has been made in understanding how to ensure that the system obeys the equipartition theorem or, equivalently, that coupling between the variables is correctly described. Then a host of techniques developed for dynamical systems can be used. Among them, probably the most powerful is the Adaptive Biasing Force method, in which thermodynamic integration and biased sampling are combined to yield very efficient estimates of pdfs. The third class of methods deals with transitions between states described

  11. Scurvy: a new problem for patients with chronic GVHD involving mucous membranes; an easy problem to resolve.

    PubMed

    Kletzel, Morris; Powers, Kim; Hayes, Meghan

    2014-08-01

    Vitamin C deficiency in developed countries is typically observed in patients with unique clinical conditions such as cystic fibrosis or anorexia nervosa, or in patients on long-term tube feeds. We report here a clinical observation in six pediatric and adolescent patients (median age 17.5 yr, range 9.8-23.5 yr) with chronic GVHD with mucous membrane involvement found to be vitamin C deficient. These patients' baseline serum vitamin C levels ranged from <0.12 to 0.94 mg/dL (normal value 0.20-1.90 mg/dL), with a mean level 0.56 ± 0.36 mg/dL and a median level 0.6 mg/dL. Among these patients, signs and symptoms of mucositis failed to respond to standard chronic GVHD therapy. After receiving treatment with 2000 mg of ascorbic acid by mouth, daily patients displayed increased serum vitamin C levels. Clinically, this correlated with a remarkable improvement in patients' mucositis and ability to eat. PMID:24816030

  12. Some thoughts on problems associated with various sampling media used for environmental monitoring

    USGS Publications Warehouse

    Horowitz, A.J.

    1997-01-01

    Modern analytical instrumentation is capable of measuring a variety of trace elements at concentrations down into the single or double digit parts-per-trillion (ng l-1) range. This holds for the three most common sample media currently used in environmental monitoring programs: filtered water, whole-water and separated suspended sediment. Unfortunately, current analytical capabilities have exceeded the current capacity to collect both uncontaminated and representative environmental samples. The success of any trace element monitoring program requires that this issue be both understood and addressed. The environmental monitoring of trace elements requires the collection of calendar- and event-based dissolved and suspended sediment samples. There are unique problems associated with the collection and chemical analyses of both types of sample media. Over the past 10 years, reported ambient dissolved trace element concentrations have declined. Generally, these decreases do not reflect better water quality, but rather improvements in the procedures used to collect, process, preserve and analyze these samples without contaminating them during these steps. Further, recent studies have shown that the currently accepted operational definition of dissolved constituents (material passing a 0.45 ??m membrane filter) is inadequat owing to sampling and processing artifacts. The existence of these artifacts raises questions about the generation of accurate, precise and comparable 'dissolved' trace element data. Suspended sediment and associated trace elements can display marked short- and long-term spatial and temporal variability. This implies that spatially representative samples only can be obtained by generating composites using depth- and width-integrated sampling techniques. Additionally, temporal variations have led to the view that the determination of annual trace element fluxes may require nearly constant (e.g., high-frequency) sampling and subsequent chemical analyses

  13. Parental Choices and Ethical Dilemmas Involving Disabilities: Special Education and the Problem of Deliberately Chosen Disabilities

    ERIC Educational Resources Information Center

    Kauffman, James M.; Hallahan, Daniel P.

    2009-01-01

    Ethical issues regarding children with disabilities have long involved their treatment after they are born. These issues remain important, but children may be deliberately created with or without characteristics that are usually thought of as disabilities. Preimplantation genetic diagnosis (PGD) and related technologies that involve human…

  14. Early Father Involvement Moderates Biobehavioral Susceptibility to Mental Health Problems in Middle Childhood

    ERIC Educational Resources Information Center

    Boyce, W. Thomas; Essex, Marilyn J.; Alkon, Abbey; Goldsmith, H. Hill; Kraemer, Helena C.; Kupfer, David J.

    2006-01-01

    Objective: To study how early father involvement and children's biobehavioral sensitivity to social contexts interactively predict mental health symptoms in middle childhood. Method: Fathers' involvement in infant care and maternal symptoms of depression were prospectively ascertained in a community-based study of child health and development in…

  15. Geometric structure in seismic data, sampling and computational inverse problems (Invited)

    NASA Astrophysics Data System (ADS)

    De Hoop, M. V.; Andersson, F.; Tricoche, X.; Xia, J.; Yeh, R.

    2013-12-01

    In (nonlinear) seismic inverse problems one requires data from available large arrays acquired for many events. These data, naturally, contain information about Earth's interior over a large range of scales. From the viewpoint of detecting broadband wavefields, however, sampling often remains a challenge. We discuss various concepts and techniques which aid in analyzing and partitioning (or decomposing) such data, including compression with a novel, multi-scale, frame of Gaussian wavepackets, graph cuts and (extended) structure tensors. We emphasize the underlying geometric structure both in the physical embedding and in the associated space where the data find a natural representation. We consider several dimensionality reduction approaches including manifold learning, and develop possible notions of distance. These enable the development of methods of comparing data, for example, within and between arrays, and comparing observed with simulated data for inverse problems and regularization. Within the context of inverse problems we briefly mention the synthesis of the Dirichlet-to-Neumann map from the data, randomized sampling and direct structured solvers of the direct problem using hierarchically semi-separable (HSS) matrices in a multi-frequency formulation enabling an efficient workflow with a large number of events.

  16. Father-involvement in a refugee sample: relations between posttraumatic stress and caregiving.

    PubMed

    van Ee, Elisa; Sleijpen, Marieke; Kleber, Rolf J; Jongmans, Marian J

    2013-12-01

    Despite increased attention to the role of fathers within families, there is still a dearth of studies on the impact of trauma on father-involvement. This study investigates the quantity of father-involvement and the influence of posttraumatic stress on the quality of involvement in a refugee and asylum seeker population. Eighty refugees and asylum seekers and their young children (aged 18-42 months) were recruited. Measures included assessment of parental trauma (Harvard Trauma Questionnaire), quantity and quality of involvement (quantity of caregiving and Emotional Availability Scales), and perception of the father-child relationship (interview). The results show that fathers were less involved in caregiving tasks and play activities than mothers. No parental gender differences were found on each of the Emotional Availability Scales. Traumatic stress symptoms negatively affected the perception and the actual quality of parent-child interaction (sensitivity, structuring, nonhostility). Nevertheless, almost all fathers described their relationship with their child as good and their child as very important to them. As the quality of father-involvement is of importance to the development of the child, traumatized fathers are as much in need of clinical intervention as mothers. Despite the impact of posttraumatic stress, refugee fathers clearly are involved in the lives of their children. Mechanisms such as a deliberate withdrawal when stressed and compensation might enable affected fathers to step into the interaction when needed, raise the quality of involvement with their child, and diminish the negative impact of stress resulting from trauma and migration. PMID:24329413

  17. Problems Involved in the Choice and Use of Materials in Airplane Construction

    NASA Technical Reports Server (NTRS)

    Brenner, Paul

    1932-01-01

    The present state of the problem of materials in airplane construction is studied on the basis of data giving the principal characteristics of different materials and showing how they affect the form of airplane parts.

  18. Prefrontal cortex involvement in creative problem solving in middle adolescence and adulthood.

    PubMed

    Kleibeuker, Sietske W; Koolschijn, P Cédric M P; Jolles, Dietsje D; Schel, Margot A; De Dreu, Carsten K W; Crone, Eveline A

    2013-07-01

    Creative cognition, defined as the generation of new yet appropriate ideas and solutions, serves important adaptive purposes. Here, we tested whether and how middle adolescence, characterized by transformations toward life independency and individuality, is a more profitable phase than adulthood for creative cognition. Behavioral and neural differences for creative problem solving in adolescents (15-17 years) and adults (25-30 years) were measured while performing a matchstick problem task (MPT) in the scanner and the creative ability test (CAT), a visuo-spatial divergent thinking task, outside the scanner. Overall performances were comparable, although MPT performance indicated an advantage for adolescents in creative problem solving. In addition, adolescents showed more activation in lateral prefrontal cortex (ventral and dorsal) during creative problem solving compared to adults. These areas correlated with performances on the MPT and the CAT performance. We discuss that extended prefrontal cortex activation in adolescence is important for exploration and aids in creative cognition. PMID:23624336

  19. The problem of multivariate classification of samples with radial (or V-shaped) chemical data.

    PubMed

    Aruga, Roberto

    2003-07-27

    On the basis of the results of previous studies, the problem of multivariate classification in the presence of the so-called radial or V-shaped data has been briefly re-examined. Taking into account that the radial data, in the absence of preliminary transformations, usually lead to classifications of samples meaningless from a chemical point of view, five different data transformations have been evaluated and compared in the case of both hypothetical and real samples (real samples, in particular, consisted of archaeological ceramic shards to be classified on the basis of provenance). The following transformations have been used: closure to 100, log row centering, log double centering, row centering, and double centering. The transformed data were then classified by means of hierarchical clustering and principal component analysis (PCA). It has been demonstrated that only the first three transformations lead to correct classifications of radial data, and the causes of this fact have been explained. PMID:18969118

  20. Some free boundary problems involving non-local diffusion and aggregation

    PubMed Central

    Carrillo, José Antonio; Vázquez, Juan Luis

    2015-01-01

    We report on recent progress in the study of evolution processes involving degenerate parabolic equations which may exhibit free boundaries. The equations we have selected follow two recent trends in diffusion theory: considering anomalous diffusion with long-range effects, which leads to fractional operators or other operators involving kernels with large tails; and the combination of diffusion and aggregation effects, leading to delicate long-term equilibria whose description is still incipient. PMID:26261360

  1. Prevalence of skin problems and leg ulceration in a sample of young injecting drug users

    PubMed Central

    2014-01-01

    Background Drug users suffer harm from the injecting process, and clinical services are reporting increasing numbers presenting with skin-related problems such as abscesses and leg ulcers. Skin breakdown can lead to long-term health problems and increased service costs and is often the first indication of serious systemic ill health. The extent of skin problems in injecting drug users has not previously been quantified empirically, and there is a dearth of robust topical literature. Where skin problems have been reported, this is often without clear definition and generic terms such as ‘soft tissue infection’ are used which lack specificity. The aim of this study was to identify the range and extent of skin problems including leg ulceration in a sample of injecting drug users. Definitions of skin problems were developed and applied to descriptions from drug users to improve rigour. Methods Data were collected in needle exchanges and methadone clinics across Glasgow, Scotland, from both current and former drug injectors using face-to-face interviews. Results Two hundred participants were recruited, of which 74% (n = 148) were males and 26% (n = 52) were females. The age range was 21–44 years (mean 35 years). Just under two thirds (64%, n = 127) were currently injecting or had injected within the last 6 months, and 36% (n = 73) had previously injected and had not injected for more than 6 months. Sixty per cent (n = 120) of the sample had experienced a skin problem, and the majority reported more than one problem. Most common were abscesses, lumps, track marks and leg ulcers. Fifteen per cent (n = 30) of all participants reported having had a leg ulcer. Conclusions This is an original empirical study which demonstrated unique findings of a high prevalence of skin disease (60%) and surprisingly high rates of leg ulceration (15%). Skin disease in injecting drug users is clearly widespread. Leg ulceration in particular is a chronic recurring

  2. Polygenic Scores Predict Alcohol Problems in an Independent Sample and Show Moderation by the Environment

    PubMed Central

    Salvatore, Jessica E.; Aliev, Fazil; Edwards, Alexis C.; Evans, David M.; Macleod, John; Hickman, Matthew; Lewis, Glyn; Kendler, Kenneth S.; Loukola, Anu; Korhonen, Tellervo; Latvala, Antti; Rose, Richard J.; Kaprio, Jaakko; Dick, Danielle M.

    2014-01-01

    Alcohol problems represent a classic example of a complex behavioral outcome that is likely influenced by many genes of small effect. A polygenic approach, which examines aggregate measured genetic effects, can have predictive power in cases where individual genes or genetic variants do not. In the current study, we first tested whether polygenic risk for alcohol problems—derived from genome-wide association estimates of an alcohol problems factor score from the age 18 assessment of the Avon Longitudinal Study of Parents and Children (ALSPAC; n = 4304 individuals of European descent; 57% female)—predicted alcohol problems earlier in development (age 14) in an independent sample (FinnTwin12; n = 1162; 53% female). We then tested whether environmental factors (parental knowledge and peer deviance) moderated polygenic risk to predict alcohol problems in the FinnTwin12 sample. We found evidence for both polygenic association and for additive polygene-environment interaction. Higher polygenic scores predicted a greater number of alcohol problems (range of Pearson partial correlations 0.07–0.08, all p-values ≤ 0.01). Moreover, genetic influences were significantly more pronounced under conditions of low parental knowledge or high peer deviance (unstandardized regression coefficients (b), p-values (p), and percent of variance (R2) accounted for by interaction terms: b = 1.54, p = 0.02, R2 = 0.33%; b = 0.94, p = 0.04, R2 = 0.30%, respectively). Supplementary set-based analyses indicated that the individual top single nucleotide polymorphisms (SNPs) contributing to the polygenic scores were not individually enriched for gene-environment interaction. Although the magnitude of the observed effects are small, this study illustrates the usefulness of polygenic approaches for understanding the pathways by which measured genetic predispositions come together with environmental factors to predict complex behavioral outcomes. PMID:24727307

  3. Prosocial Involvement and Antisocial Peer Affiliations as Predictors of Behavior Problems in Urban Adolescents: Main Effects and Moderating Effects

    ERIC Educational Resources Information Center

    Kaufmann, Dagmar R.; Wyman, Peter A.; Forbes-Jones, Emma L.; Barry, Jason

    2007-01-01

    This study examined the relationships between prosocial involvement (PI), antisocial peer affiliations (APA), and the degree of their overlapping or independent prediction of behavior problems in urban adolescents. Two dimensions of behavior were assessed at ages 9-11 and at ages 13-15: disruptive, aggressive conduct and number of delinquent…

  4. "What Brings Him Here Today?": Medical Problem Presentation Involving Children with Autism Spectrum Disorders and Typically Developing Children

    ERIC Educational Resources Information Center

    Solomon, Olga; Heritage, John; Yin, Larry; Maynard, Douglas W.; Bauman, Margaret L.

    2016-01-01

    Conversation and discourse analyses were used to examine medical problem presentation in pediatric care. Healthcare visits involving children with ASD and typically developing children were analyzed. We examined how children's communicative and epistemic capabilities, and their opportunities to be socialized into a competent patient role are…

  5. Social Competency Training Goes to School: Pupil Involvement in the Classroom through Problem-Solving with People.

    ERIC Educational Resources Information Center

    Hallarman, Prudence R.; And Others

    The need for a "systems" approach to school-based social competency training has been highlighted by a national commission and the U.S. Department of Education. The Pupil Involvement/Problem-Solving with People (PI/PSP) curriculum has adapted numerous, well-researched social compentency training models targeted for elementary classroom use.…

  6. Geostatistical Sampling Methods for Efficient Uncertainty Analysis in Flow and Transport Problems

    NASA Astrophysics Data System (ADS)

    Liodakis, Stylianos; Kyriakidis, Phaedon; Gaganis, Petros

    2015-04-01

    In hydrogeological applications involving flow and transport of in heterogeneous porous media the spatial distribution of hydraulic conductivity is often parameterized in terms of a lognormal random field based on a histogram and variogram model inferred from data and/or synthesized from relevant knowledge. Realizations of simulated conductivity fields are then generated using geostatistical simulation involving simple random (SR) sampling and are subsequently used as inputs to physically-based simulators of flow and transport in a Monte Carlo framework for evaluating the uncertainty in the spatial distribution of solute concentration due to the uncertainty in the spatial distribution of hydraulic con- ductivity [1]. Realistic uncertainty analysis, however, calls for a large number of simulated concentration fields; hence, can become expensive in terms of both time and computer re- sources. A more efficient alternative to SR sampling is Latin hypercube (LH) sampling, a special case of stratified random sampling, which yields a more representative distribution of simulated attribute values with fewer realizations [2]. Here, term representative implies realizations spanning efficiently the range of possible conductivity values corresponding to the lognormal random field. In this work we investigate the efficiency of alternative methods to classical LH sampling within the context of simulation of flow and transport in a heterogeneous porous medium. More precisely, we consider the stratified likelihood (SL) sampling method of [3], in which attribute realizations are generated using the polar simulation method by exploring the geometrical properties of the multivariate Gaussian distribution function. In addition, we propose a more efficient version of the above method, here termed minimum energy (ME) sampling, whereby a set of N representative conductivity realizations at M locations is constructed by: (i) generating a representative set of N points distributed on the

  7. Variants of callous-unemotional conduct problems in a community sample of adolescents.

    PubMed

    Fanti, Kostas A; Demetriou, Chara A; Kimonis, Eva R

    2013-07-01

    Callous-unemotional traits are believed to be a childhood precursor to psychopathy, and among youth with conduct problems they designate those showing a particularly severe, stable, and aggressive pattern of antisocial behavior. Youth with callous-unemotional traits are a heterogeneous population and, analogous to adults with psychopathy, research suggests that lower anxious primary and high-anxious secondary variants exist. Using a community sample of 2,306 Greek-Cypriot adolescents (M age = 16 years; 49.7 % female), the first aim of the study was to examine whether variants of callous-unemotional traits could be identified using latent profile analysis of scores on measures of callous-unemotional traits, conduct problems, and anxiety. Additional aims of the study were to compare the identified clusters on external measures theorized to distinguish them (i.e., self-esteem, narcissism, impulsivity, sensation seeking and proactive/reactive aggression) and social factors relevant to adolescent development. Results indicated that, in addition to low risk (i.e., low scores on callous-unemotional traits, conduct problems, and anxiety) and anxious (i.e., high scores on anxiety, low scores on callous-unemotional traits and conduct problems) subgroups, two groups of youth scoring high on callous-unemotional traits and conduct problems were identified. High-anxious secondary callous-unemotional variants were distinguished by lower self-esteem in combination with greater narcissism, aggression, and markedly higher conduct problems, whereas lower anxious primary variants showed higher self-esteem. Secondary callous-unemotional variants also reported greater susceptibility to peer pressure and popularity striving than primary variants. Both variants exhibited poorer outcomes relative to low risk and anxious youth, although anxious youth reported lower self-esteem and higher impulsivity and reactive aggression scores in comparison with low risk youth. Findings integrate two

  8. Protective Role of Religious Involvement Against Depression and Suicidal Ideation Among Youth with Interpersonal Problems.

    PubMed

    Cole-Lewis, Yasmin C; Gipson, Polly Y; Opperman, Kiel J; Arango, Alejandra; King, Cheryl A

    2016-08-01

    This study examined religious involvement-private religious practices (PRP), organizational religiousness (OR), and religious support (RS)-in relation to depressive symptoms and suicidal ideation (SI) and its protective role, considering youths' school and parent-family connectedness. Youth, ages 12-15 (n = 161), were screened for peer victimization, bullying perpetration, and low social connectedness, and assessed for depressive symptoms, SI, school connectedness, parent-family connectedness, and religious involvement. Results indicated PRP and RS were associated with lower levels of depressive symptoms; PRP and OR were associated with less SI. Controlling for connectedness, PRP remained associated with less SI only. Results suggest the importance of considering religious involvement as a target of youth depression and suicide prevention interventions. PMID:26872965

  9. Involvement in a Current Problem as a Basis for Writing (Instructional Note).

    ERIC Educational Resources Information Center

    Guiher-Huff, Susan

    1990-01-01

    Describes a freshman composition class in which students write essays about pollution. Explains that students classified and divided problems, cited examples, explored pollution's processes, used narrative, and offered comparisons. Describes how students prepared cause-and-effect oral presentations and then wrote persuasive letters. Concludes that…

  10. Interval-Valued Optimization Problems Involving (α, ρ)-Right Upper-Dini-Derivative Functions

    PubMed Central

    2014-01-01

    We consider an interval-valued multiobjective problem. Some necessary and sufficient optimality conditions for weak efficient solutions are established under new generalized convexities with the tool-right upper-Dini-derivative, which is an extension of directional derivative. Also some duality results are proved for Wolfe and Mond-Weir duals. PMID:24982989

  11. Interval-valued optimization problems involving (α, ρ)-right upper-Dini-derivative functions.

    PubMed

    Preda, Vasile

    2014-01-01

    We consider an interval-valued multiobjective problem. Some necessary and sufficient optimality conditions for weak efficient solutions are established under new generalized convexities with the tool-right upper-Dini-derivative, which is an extension of directional derivative. Also some duality results are proved for Wolfe and Mond-Weir duals. PMID:24982989

  12. Skipping Out on Alma Mater: Some Problems Involving the Collection of Federal Student Loans.

    ERIC Educational Resources Information Center

    Leonard, Kevin J.

    1980-01-01

    Present law respecting collection of federal student loans, regulatory and other sanctions against default, and strategies against bankruptcy are outlined and analyzed. (Journal availability: Columbia Journal of Law and Social Problems, Box 7, Columbia University School of Law, 435 W. 116th St., New York, NY 10027, $5.00.) (MSE)

  13. Gender and Environmental Sustainability: Issues and Problems Involved for Persons with Special Needs in Nigeria

    ERIC Educational Resources Information Center

    Egaga, Patrick I.; Aderibigbe, S. Akinwumi

    2015-01-01

    Sustainability of the environment is one of the major problems facing African people, most especially Nigerians. It is unfortunate that women, by the nature of their daily activities of managing the homes and families are in touch with nature and environment and are at greater risk of health hazards and foetal damage. This paper focuses on the…

  14. Learning Contemporary Problems through Community Involvement. A Senior Social Studies Elective.

    ERIC Educational Resources Information Center

    Eagan, Julianne; Freitas, Kevin

    A critical exploration of the meaning and function of community is the focus of this curriculum unit. It is proposed that students develop projects that are designed to contribute to a community in which they are involved, positing that the leadership and networking skills these students develop over the course of the semester provide them with…

  15. Father Involvement, Dating Violence, and Sexual Risk Behaviors Among a National Sample of Adolescent Females.

    PubMed

    Alleyne-Green, Binta; Grinnell-Davis, Claudette; Clark, Trenette T; Quinn, Camille R; Cryer-Coupet, Qiana R

    2016-03-01

    This study explored the relationship between the involvement of biological fathers and the sexual risk behaviors and dating violence/victimization and/or perpetration of adolescent girls. The data used in this cross-sectional analysis were drawn from the second wave of the public release of the National Longitudinal Study of Adolescent Health. Only adolescents who reported their biological sex as female, reported a history of being sexually active, and reported having a romantic partner in the previous 18 months were selected (N = 879). This study focused on overall positive sexual behaviors and use of contraception. Structural equation modeling (SEM) was used to best utilize capacity for dealing with latent variables and to test for possible mediation effects. The analysis demonstrated main effects of dating violence and father involvement on sexual behaviors. The more dating violence an adolescent girl experiences, the less likely she is to engage in healthy sexual behaviors. Likewise, the more involvement the biological father has in a woman's life, the more likely she is to engage in positive sexual behaviors. Perceived father involvement was associated with risky sexual behaviors among sexually experienced adolescent girls. Dating violence was directly associated with risky sexual behaviors among sexually experienced adolescent girls, particularly non-White girls. Future studies should use longitudinal models and test theoretically and empirically guided potential mediators. Future studies should also consider father figures such as step-fathers and grandfathers in addition to biological fathers, as having a father figure may be a stronger predictor of adolescent sexual behaviors than having a biological connection. PMID:25475102

  16. Father Involvement, Dating Violence, and Sexual Risk Behaviors Among a National Sample of Adolescent Females

    PubMed Central

    Alleyne-Green, Binta; Grinnell-Davis, Claudette; Clark, Trenette T.; Quinn, Camille R.; Cryer, Qiana R.

    2016-01-01

    This study explored the relationship between the involvement of biological fathers and the sexual risk behaviors and dating violence/victimization and/ or perpetration of adolescent girls. The data used in this cross-sectional analysis were drawn from the second wave of the public release of the National Longitudinal Study of Adolescent Health. Only adolescents who reported their biological sex as female, reported a history of being sexually active, and reported having a romantic partner in the previous 18 months were selected (N = 879). This study focused on overall positive sexual behaviors and use of contraception. Structural equation modeling (SEM) was used to best utilize capacity for dealing with latent variables and to test for possible mediation effects. The analysis demonstrated main effects of dating violence and father involvement on sexual behaviors. The more dating violence an adolescent girl experiences, the less likely she is to engage in healthy sexual behaviors. Likewise, the more involvement the biological father has in a woman’s life, the more likely she is to engage in positive sexual behaviors. Perceived father involvement was associated with risky sexual behaviors among sexually experienced adolescent girls. Dating violence was directly associated with risky sexual behaviors among sexually experienced adolescent girls, particularly non-White girls. Future studies should use longitudinal models and test theoretically and empirically guided potential mediators. Future studies should also consider father figures such as step-fathers and grandfathers in addition to biological fathers, as having a father figure may be a stronger predictor of adolescent sexual behaviors than having a biological connection. PMID:25475102

  17. Symptoms of Major Depression in a Sample of Fathers of Infants: Sociodemographic Correlates and Links to Father Involvement

    ERIC Educational Resources Information Center

    Bronte-Tinkew, Jacinta; Moore, Kristin A.; Matthews, Gregory; Carrano, Jennifer

    2007-01-01

    Depression has been extensively studied for mothers but not for fathers. This study examines the sociodemographic correlates of symptoms of depression and how depression is associated with father involvement using the Composite International Diagnostic Interview-Short Form (CIDI-SF) for major depression. The study uses a sample of 2,139 resident…

  18. Joint Associations of Residential Density and Neighborhood Involvement with Physical Activity among a Multiethnic Sample of Urban Adults

    ERIC Educational Resources Information Center

    Johnson-Lawrence, Vicki; Schulz, Amy J.; Zenk, Shannon N.; Israel, Barbara A.; Wineman, Jean; Marans, Robert W.; Rowe, Zachary

    2015-01-01

    Regular physical activity is associated with improvements in overall health. Although resident involvement in neighborhood social activities is positively associated with physical activity, neighborhood design features, including residential density, have varied associations with physical activity. Using data from a multiethnic sample of 696…

  19. Comparing the effects of problem-based and conventional curricula in an international sample.

    PubMed

    Schmidt, H G; Dauphinee, W D; Patel, V L

    1987-04-01

    In this article, the authors review 15 studies that compare various educational outcomes of problem-based, community-oriented medical curricula with those of conventional programs. The data suggest that problem-based curricula provide a student-centered learning environment and encourage an inquisitive style of learning in their students as opposed to the rote memorization and short-term learning strategies induced by conventional medical education. In addition, community-oriented schools appear to influence the career preferences of their students. The few data available show that significantly larger proportions of graduates from these schools seek careers in primary care. Some of the studies reviewed suggest that students in conventional programs perform somewhat better on traditional measures of academic achievement than do students in problem-based curricula. However, these differences, if any, tend to be very small. Data with respect to performance on instruments measuring clinical competence are inconclusive. Finally, the authors discuss the difficulties involved in carrying out comparative research at the curriculum level. PMID:3560175

  20. Approximation methods for inverse problems involving the vibration of beams with tip bodies

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.

    1984-01-01

    Two cubic spline based approximation schemes for the estimation of structural parameters associated with the transverse vibration of flexible beams with tip appendages are outlined. The identification problem is formulated as a least squares fit to data subject to the system dynamics which are given by a hybrid system of coupled ordinary and partial differential equations. The first approximation scheme is based upon an abstract semigroup formulation of the state equation while a weak/variational form is the basis for the second. Cubic spline based subspaces together with a Rayleigh-Ritz-Galerkin approach were used to construct sequences of easily solved finite dimensional approximating identification problems. Convergence results are briefly discussed and a numerical example demonstrating the feasibility of the schemes and exhibiting their relative performance for purposes of comparison is provided.

  1. Exact sampling of the unobserved covariates in Bayesian spline models for measurement error problems

    PubMed Central

    Carroll, Raymond J.

    2015-01-01

    In truncated polynomial spline or B-spline models where the covariates are measured with error, a fully Bayesian approach to model fitting requires the covariates and model parameters to be sampled at every Markov chain Monte Carlo iteration. Sampling the unobserved covariates poses a major computational problem and usually Gibbs sampling is not possible. This forces the practitioner to use a Metropolis–Hastings step which might suffer from unacceptable performance due to poor mixing and might require careful tuning. In this article we show for the cases of truncated polynomial spline or B-spline models of degree equal to one, the complete conditional distribution of the covariates measured with error is available explicitly as a mixture of double-truncated normals, thereby enabling a Gibbs sampling scheme. We demonstrate via a simulation study that our technique performs favorably in terms of computational efficiency and statistical performance. Our results indicate up to 62 and 54 % increase in mean integrated squared error efficiency when compared to existing alternatives while using truncated polynomial splines and B-splines respectively. Furthermore, there is evidence that the gain in efficiency increases with the measurement error variance, indicating the proposed method is a particularly valuable tool for challenging applications that present high measurement error. We conclude with a demonstration on a nutritional epidemiology data set from the NIH-AARP study and by pointing out some possible extensions of the current work. PMID:27418743

  2. Medical Problems in a Sample of Children with Intellectual Impairments in Jordan.

    ERIC Educational Resources Information Center

    Yousef, Jamal M. S.

    1993-01-01

    Medical problems of 262 children attending special schools for persons having intellectual impairments in Jordan were examined. The most common problems were neurological problems (affecting 38.55%), followed by dental disease, orthopedic problems, vision and eye problems, hearing/ear problems, urinary diseases, and heart problems. (JDD)

  3. Condom use errors and problems in a national sample of young Croatian adults.

    PubMed

    Baćak, Valerio; Stulhofer, Aleksandar

    2012-08-01

    In this study, we examined the correlates of condom use errors and problems in a population-based study conducted in 2010 among young Croatian adults aged 18-25 years. Out of a total sample of 1,005 participants, 679 reported condom use in the preceding year. The analyses focused on four outcomes: condom breakage, condom slippage, condom-related erection loss, and delayed condom application. Eighteen percent of participants experienced breakage, 13% reported slippage, 17% reported erection loss, and 34% applied a condom after intercourse started. Multivariate logistic regression analyses were performed to examine the correlates of these condom use errors and problems. Condom breakage was less likely to be reported by women and older participants. The odds of breakage were increased for participants who reported being under the influence of drugs during sex and who reported other condom use errors and problems in the past year. Condom slippage was more likely to occur among younger participants and those who reported condom breakage and delayed condom application. Condom-related erection loss was positively associated with a higher number of sexual partners in the preceding year, condom breakage, and a higher score on the Anti-Erotic Obstacles to Condom Use Scale. Odds of delayed condom application were increased for participants who experienced condom breakage and for those who consumed alcohol before sex in the past year. Having used a condom at first sex significantly reduced the odds of applying a condom after intercourse started. In comparison to non-habitual condom users, habitual users were found less likely to report any of the assessed condom use errors and problems. Improving condom use skills remains an important task in Croatia, which is currently hampered by the absence of evidence-based sex education in schools. PMID:21882054

  4. Trans-dimensional Monte Carlo sampling applied to the magnetotelluric inverse problem

    NASA Astrophysics Data System (ADS)

    Mandolesi, Eric; Piana Agostinetti, Nicola

    2015-01-01

    The data required to build geological models of the subsurface are often unavailable from direct measurements or well logs. In order to image the subsurface geological structures several geophysical methods have been developed. The magnetotelluric (MT) method uses natural, time-varying electromagnetic (EM) fields as its source to measure the EM impedance of the subsurface. The interpretation of these data is routinely undertaken by solving inverse problems to produce 1D, 2D or 3D electrical conductivity models of the subsurface. In classical MT inverse problems the investigated models are parametrized using a fixed number of unknowns (i.e. fixed number of layers in a 1D model, or a fixed number of cells in a 2D model), and the non-uniqueness of the solution is handled by a regularization term added to the objective function. This study presents a different approach to the 1D MT inverse problem, by using a trans-dimensional Monte Carlo sampling algorithm, where trans-dimensionality implies that the number of unknown parameters is a parameter itself. This construction has been shown to have a built-in Occam razor, so that the regularization term is not required to produce a simple model. The influences of subjective choices in the interpretation process can therefore be sensibly reduced. The inverse problem is solved within a Bayesian framework, where posterior probability distribution of the investigated parameters are sought, rather than a single best-fit model, and uncertainties on the model parameters, and their correlation, can be easily measured.

  5. Identifying Depression in a National Sample of Caregivers Involved with Child Welfare

    PubMed Central

    Chuang, Emmeline; Wells, Rebecca; Aarons, Gregory A

    2014-01-01

    Objectives Identifying depression is the first step in provision of treatment across service settings but can be challenging for non-mental health providers. This study examines how caseworker identification of depression among parents and other caregivers during the child welfare investigation or assessment process varies as a function of different agency, caseworker, and case characteristics. Methods Data were drawn from the second National Survey of Child and Adolescent Well-Being (NSCAW II), a national probability sample of children referred to U.S. child welfare agencies between February 2008 and April 2009. The study sample was comprised of 889 parents and other caregivers whose children initially remained at home and whose confidential responses on the World Health Organization Composite International Diagnostic Interview Short-Form indicated a major depressive episode within the last 12 months. Weighted logistic regression examined predictors of caseworker identification of caregiver depression at the agency, caseworker, and case level. Results Investigative caseworkers identified mental health needs in only 38% of caregivers. Caseworkers were more likely to identify caregiver mental health needs when child welfare agency policy specified use of a standardized mental health assessment and when the maltreatment report came from a health or mental health provider relative to other sources, such as teachers or family members. Investigative caseloads were negatively associated with identifying depression. Conclusions Structured mental health assessments may help non-mental health professionals identify mental health needs among vulnerable populations. PMID:24686832

  6. Psychometric Analyses of the Problem-Focused Style of Coping (PF-SOC) Scale with Taiwanese Samples

    ERIC Educational Resources Information Center

    Chang, Yuhsuan; Lan, Yu-Ling; Lin, Hung-Yu; Heppner, Puncky Paul

    2012-01-01

    The current research comprises two samples that investigated the psychometric properties of the Problem-Focused Style of Coping (PF-SOC; Heppner, Cook, Wright, & Johnson) scale using two Taiwanese samples. In Sample 1 (N = 809), we investigated the structural dimensions of the PF-SOC using a principal component analysis (PCA) and confirmed three…

  7. Infinitely many solutions for the stationary Kirchhoff problems involving the fractional p-Laplacian

    NASA Astrophysics Data System (ADS)

    Mingqi, Xiang; Molica Bisci, Giovanni; Tian, Guohua; Zhang, Binlin

    2016-02-01

    The aim of this paper is to establish the multiplicity of weak solutions for a Kirchhoff-type problem driven by a fractional p-Laplacian operator with homogeneous Dirichlet boundary conditions: where Ω is an open bounded subset of {{{R}}N} with Lipshcitz boundary \\partial Ω , (-Δ )ps is the fractional p-Laplacian operator with 0  <  s  <  1  <  p  <  N such that sp  <  N, M is a continuous function and f is a Carathéodory function satisfying the Ambrosetti-Rabinowitz-type condition. When f satisfies the suplinear growth condition, we obtain the existence of a sequence of nontrivial solutions by using the symmetric mountain pass theorem; when f satisfies the sublinear growth condition, we obtain infinitely many pairs of nontrivial solutions by applying the Krasnoselskii genus theory. Our results cover the degenerate case in the fractional setting: the Kirchhoff function M can be zero at zero.

  8. Service use after court involvement in a sample of serious adolescent offenders

    PubMed Central

    Mulvey, Edward P.; Schubert, Carol A.; Chung, He Len

    2009-01-01

    The juvenile justice system faces a difficult challenge when providing services to serious adolescent offenders, having to balance community safety concerns with hopes for successful intervention. Increasing the effectiveness of this system rests partially on having a clearer picture of the regularities of current service provision to these adolescents. This study describes the types of services received by a large (N=868) sample of adjudicated serious offenders from two metropolitan areas over a two-year follow-up period after adjudication in court, and examines whether indicators of need for services determine the types of services received in the juvenile justice system. Findings indicate that: 1) the level of specialized services received is rather low, 2) there is considerable site variability, 3) the service needs of adolescents sent to different types of settings appear to be generally equivalent, 4) state training schools appear to provide about the same level of services found in contracted provider settings, and 5) need is an inconsistent determinant of service provision. PMID:19907667

  9. Vital Involvement Practice: strengths as more than tools for solving problems.

    PubMed

    Kivnick, Helen Q; Stoffel, Sharon A

    2005-01-01

    This article describes Vital Involvement Practice, a strength-based approach to clinical practice with elders, including those who are extremely frail. Using this approach, practitioners have been able to help elders increase later-life vitality and associated positive quality of life through: (1) systematic identification of individual strengths and assets (found both in the person and in the surrounding environment), and (2) consideration of these strengths alongside the individual and environmental deficits that are the subject of most geriatric practice. The approach utilizes original data-gathering tools (Occupational Profile; Life Strengths Interview Guide) and a stepwise, worksheet- structured consideration of these data in order to formulate action strategies for achieving client goals (Domain Scan; Domain Goals; Life Plan/Strategy). All elements of VIP emerged in pilot work with gerontological practitioners and their elder clients in such settings as: primary health care; government social service; subsidized senior housing; private clinical practice; community recreation. Limitations, implications, and promise are noted, with respect to practice and research. PMID:16368677

  10. A lunar-based analytical laboratory and contamination problems in analysis of Moon and Mars samples

    NASA Astrophysics Data System (ADS)

    Gehrke, Charles W.

    1997-07-01

    A summary follows of our experiences and techniques used in the analysis of samples from Apollo Missions 11 to 17. The studies were conducted at the Ames Research Center, Moffett Field, CA, the University of Missouri, Columbia, MO, and the University of Maryland, College Park, MD, 1969 - 1974. Our search was directed to water-extractable compounds with emphasis on amino acids. Gas chromatography, ion-exchange chromatography and gas chromatography combined with mass spectrometry were used for the analysis. It is our conclusion that amino acids are not present in the lunar regolith above the background levels of our investigation (ca. 1 - 3 ng/g). The scientific debate has become heated that primitive life existed on Mars 3.6 billion years ago as reported by the NASA-Stanford team led to David McKay. Mars is destined to receive humans early in the 21st Century, preceded by many international missions to Space Station Freedom and robotic missions to the Moon and Mars. First, we must `learn to live in space'. The Moon presents a base that provides the opportunities and challenges to assemble the international interdisciplinary intellectual scientific teams and partners with many disciplines to make the next step before human exploration of Mars and the search for evidence in Martian soil and samples returned to Earth laboratories. Our experiences learned in Moon analysis will be useful in Mars exploration and returned sample study. Sensitivity at the nanogram/gram level and selectivity of analysis are highly essential. As these figures show contamination of samples is a most serious problem. However with the use of ultraclean techniques in a 100 clean room contamination can be avoided. Our speck of dust, a tiny fragment of cigarette smoke, a particle of dandruff, a droplet of saliva, all can make your results questionable. In addition, the extraction of life molecules as amino acids from the Lunar samples was a difficult process and I am sure the same difficulties

  11. The role of parenting in the prediction of criminal involvement: findings from a nationally representative sample of youth and a sample of adopted youth.

    PubMed

    Beaver, Kevin M; Schwartz, Joseph A; Connolly, Eric J; Al-Ghamdi, Mohammed Said; Kobeisy, Ahmed Nezar

    2015-03-01

    The role of parenting in the development of criminal behavior has been the source of a vast amount of research, with the majority of studies detecting statistically significant associations between dimensions of parenting and measures of criminal involvement. An emerging group of scholars, however, has drawn attention to the methodological limitations-mainly genetic confounding-of the parental socialization literature. The current study addressed this limitation by analyzing a sample of adoptees to assess the association between 8 parenting measures and 4 criminal justice outcome measures. The results revealed very little evidence of parental socialization effects on criminal behavior before controlling for genetic confounding and no evidence of parental socialization effects on criminal involvement after controlling for genetic confounding. PMID:25602937

  12. The Relationship between Motor Skills, Perceived Social Support, and Internalizing Problems in a Community Adolescent Sample

    PubMed Central

    Mancini, Vincent O.; Rigoli, Daniela; Heritage, Brody; Roberts, Lynne D.; Piek, Jan P.

    2016-01-01

    Objectives: Poor motor skills are associated with a range of psychosocial consequences, including internalizing (anxious and depressive) symptoms. The Elaborated Environmental Stress Hypothesis provides a causal framework to explain this association. The framework posits that motor skills impact internalizing problems through an indirect effect via perceived social support. However, empirical evaluation is required. We examined whether motor skills had an indirect effect on anxious and depressive symptoms via perceived family support domains. Methods: This study used a community sample of 93 adolescents (12–16 years). Participants completed measures of motor skills, perceived social support across three dimensions (family, friend, and significant other), depressive symptoms, and anxious symptoms. Age, gender, verbal IQ, and ADHD symptoms were included as control variables. Results: Regression analysis using PROCESS revealed that motor skills had an indirect effect on depressive symptoms via perceived family support, but not by perceived friend support or significant other support. The negative association between motor skills and anxious symptoms was not mediated by any perceived social support domain. Conclusions: Findings are consistent with previous literature indicating an association between motor skills and internalizing problems. However, we identified a different pattern of relationships across anxious and depressive symptoms. While anxiety and depressive symptoms were highly correlated, motor skills had an indirect effect on depressive symptoms via perceived family support only. Our findings highlight the importance of family support as a potential protective factor in the onset of depressive symptoms. This study provides partial support for the Elaborated Environmental Stress Hypothesis, however further research is required. PMID:27148149

  13. Sample problem calculations related to two-phase flow transients in a PWR relief-piping network

    SciTech Connect

    Shin, Y.W.; Wiedermann, A.H.

    1981-03-01

    Two sample problems related with the fast transients of water/steam flow in the relief line of a PWR pressurizer were calculated with a network-flow analysis computer code STAC (System Transient-Flow Analysis Code). The sample problems were supplied by EPRI and are designed to test computer codes or computational methods to determine whether they have the basic capability to handle the important flow features present in a typical relief line of a PWR pressurizer. It was found necessary to implement into the STAC code a number of additional boundary conditions in order to calculate the sample problems. This includes the dynamics of the fluid interface that is treated as a moving boundary. This report describes the methodologies adopted for handling the newly implemented boundary conditions and the computational results of the two sample problems. In order to demonstrate the accuracies achieved in the STAC code results, analytical solutions are also obtained and used as a basis for comparison.

  14. Accuracy Study of the Space-Time CE/SE Method for Computational Aeroacoustics Problems Involving Shock Waves

    NASA Technical Reports Server (NTRS)

    Wang, Xiao Yen; Chang, Sin-Chung; Jorgenson, Philip C. E.

    1999-01-01

    The space-time conservation element and solution element(CE/SE) method is used to study the sound-shock interaction problem. The order of accuracy of numerical schemes is investigated. The linear model problem.govemed by the 1-D scalar convection equation, sound-shock interaction problem governed by the 1-D Euler equations, and the 1-D shock-tube problem which involves moving shock waves and contact surfaces are solved to investigate the order of accuracy of numerical schemes. It is concluded that the accuracy of the CE/SE numerical scheme with designed 2nd-order accuracy becomes 1st order when a moving shock wave exists. However, the absolute error in the CE/SE solution downstream of the shock wave is on the same order as that obtained using a fourth-order accurate essentially nonoscillatory (ENO) scheme. No special techniques are used for either high-frequency low-amplitude waves or shock waves.

  15. Methods for calculating the entropy and free energy and their application to problems involving protein flexibility and ligand binding

    PubMed Central

    Meirovitch, Hagai; Cheluvaraja, Srinath; White, Ronald P.

    2009-01-01

    The Helmholtz free energy, F and the entropy, S are related thermodynamic quantities with a special importance in structural biology. We describe the difficulties in calculating these quantities and review recent methodological developments. Because protein flexibility is essential for function and ligand binding, we discuss the related problems involved in the definition, simulation, and free energy calculation of microstates (such as the α-helical region of a peptide). While the review is broad, a special emphasize is given to methods for calculating the absolute F (S), where our HSMC(D) method is described in some detail. PMID:19519453

  16. Moonrise: Sampling the South Pole-Aitken Basin to Address Problems of Solar System Significance

    NASA Technical Reports Server (NTRS)

    Zeigler, R. A.; Jolliff, B. L.; Korotev, R. L.; Shearer, C. K.

    2016-01-01

    A mission to land in the giant South Pole-Aitken (SPA) Basin on the Moon's southern farside and return a sample to Earth for analysis is a high priority for Solar System Science. Such a sample would be used to determine the age of the SPA impact; the chronology of the basin, including the ages of basins and large impacts within SPA, with implications for early Solar System dynamics and the magmatic history of the Moon; the age and composition of volcanic rocks within SPA; the origin of the thorium signature of SPA with implications for the origin of exposed materials and thermal evolution of the Moon; and possibly the magnetization that forms a strong anomaly especially evident in the northern parts of the SPA basin. It is well known from studies of the Apollo regolith that rock fragments found in the regolith form a representative collection of many different rock types delivered to the site by the impact process (Fig. 1). Such samples are well documented to contain a broad suite of materials that reflect both the local major rock formations, as well as some exotic materials from far distant sources. Within the SPA basin, modeling of the impact ejection process indicates that regolith would be dominated by SPA substrate, formed at the time of the SPA basin-forming impact and for the most part moved around by subsequent impacts. Consistent with GRAIL data, the SPA impact likely formed a vast melt body tens of km thick that took perhaps several million years to cool, but that nonetheless represents barely an instant in geologic time that should be readily apparent through integrated geochronologic studies involving multiple chronometers. It is anticipated that a statistically significant number of age determinations would yield not only the age of SPA but also the age of several prominent nearby basins and large craters within SPA. This chronology would provide a contrast to the Imbrium-dominated chronology of the nearside Apollo samples and an independent test of

  17. Information Processing Profiles of Internalizing and Externalizing Behavior Problems: Evidence from a Population-Based Sample of Preadolescents

    ERIC Educational Resources Information Center

    Brunnekreef, J. Agnes; De Sonneville, Leo M. J.; Althaus, Monika; Minderaa, Ruud B.; Oldehinkel, Albertine J.; Verhulst, Frank C.; Ormel, Johan

    2007-01-01

    Background: The present study explores the relationships between several information processing capacities and internalizing and externalizing behavior problems in a general population sample of 10- to 12-year olds (N = 2,037 51% girls). Methods: Parent-reported behavior problems as assessed by the Child Behavior Checklist were used to form four…

  18. Eating Problems and Their Risk Factors: A 7-Year Longitudinal Study of a Population Sample of Norwegian Adolescent Girls

    ERIC Educational Resources Information Center

    Kansi, Juliska; Wichstrom, Lars; Bergman, Lars R.

    2005-01-01

    The longitudinal stability of eating problems and their relationships to risk factors were investigated in a representative population sample of 623 Norwegian girls aged 13-14 followed over 7 years (3 time points). Three eating problem symptoms were measured: Restriction, Bulimia-food preoccupation, and Diet, all taken from the 12-item Eating…

  19. Levels and types of alcohol biomarkers in DUI and clinic samples for estimating workplace alcohol problems.

    PubMed

    Marques, Paul R

    2012-02-01

    Widespread concern about illicit drugs as an aspect of workplace performance potentially diminishes attention on employee alcohol use. Alcohol is the dominant drug contributing to poor job performance; it also accounts for a third of the worldwide public health burden. Evidence from public roadways--a workplace for many--provides an example of work-related risk exposure and performance lapses. In most developed countries, alcohol is involved in 20-35% of fatal crashes; drugs other than alcohol are less prominently involved in fatalities. Alcohol biomarkers can improve detection by extending the timeframe for estimating problematic exposure levels and thereby provide better information for managers. But what levels and which markers are right for the workplace? In this paper, an established high-sensitivity proxy for alcohol-driving risk proclivity is used: an average eight months of failed blood alcohol concentration (BAC) breath tests from alcohol ignition interlock devices. Higher BAC test fail rates are known to presage higher rates of future impaired-driving convictions (driving under the influence; DUI). Drivers in alcohol interlock programmes log 5-7 daily BAC tests; in 12 months, this yields thousands of samples. Also, higher programme entry levels of alcohol biomarkers predict a higher likelihood of failed interlock BAC tests during subsequent months. This paper summarizes the potential of selected biomarkers for workplace screening. Markers include phosphatidylethanol (PEth), percent carbohydrate deficient transferrin (%CDT), gammaglutamyltransferase (GGT), gamma %CDT (γ%CDT), and ethylglucuronide (EtG) in hair. Clinical cut-off levels and median/mean levels of these markers in abstinent people, the general population, DUI drivers, and rehabilitation clinics are summarized for context. PMID:22311827

  20. Negative Peer Involvement in Multisystemic Therapy for the Treatment of Youth Problem Behavior: Exploring Outcome and Process Variables in "Real-World" Practice

    ERIC Educational Resources Information Center

    Boxer, Paul

    2011-01-01

    Associating with a negative peer group is related to involvement in problem behavior, yet very little research has considered the role of negative peer group affiliations in the context of "real-world" community-based treatments for problem behavior. This study examined the effects of negative peer involvement on case closure status and treatment…

  1. Stability of Self-Reported Arousal to Sexual Fantasies Involving Children in a Clinical Sample of Pedophiles and Hebephiles.

    PubMed

    Grundmann, Dorit; Krupp, Jurian; Scherner, Gerold; Amelung, Till; Beier, Klaus M

    2016-07-01

    In forensic research, there is a controversial discussion concerning the changeability or stability of pedophilia. Seto (2012) conceptualized pedophilia as a sexual age orientation characterized by an early onset, correlations with sexual and romantic behavior, and stability over time. However, empirical data are sparse and are mostly based on samples of detected offenders. The present study examined self-reported arousal to sexual fantasies involving children in a clinical sample of pedo-/hebephiles. In Study 1, retrospective self-reports on the age of onset and duration of sexual interest in minors were examined. In Study 2, the stability and variability of self-reported arousal to sexual fantasies involving children were evaluated prospectively. Non-prosecuted self-identifying pedo-/hebephilic men seeking professional help were recruited within the Berlin Prevention Project Dunkelfeld. Between 2005 and 2013, 494 participants completed the intake assessment. Self-reported data were collected via questionnaire focusing on sexual arousal to fantasies during masturbation involving prepubescent and/or early pubescent minors. Subsequent assessments of sexual arousal were obtained for 121 of the participants. The average time between the first and last assessment was approximately 29 months. Spearman's correlation coefficients examined the between-group rank-order and Wilcoxon signed-rank tests examined the within-individual mean-level stability. The majority of subjects reported an early onset of their pedo-/hebephilic sexual arousal. The rank-order stability was medium to high. Over the investigated period, the majority of subjects showed no or only minimal decrease or increase of self-reported sexual arousal. These results suggested that sexual arousal to fantasies involving prepubescent and/or early pubescent children is stable. Furthermore, the results support the conceptualization of pedo-/hebephilia as a sexual age orientation in men. PMID:27113471

  2. Temporal Stability of DSM-5 Posttraumatic Stress Disorder Criteria in a Problem Drinking Sample

    PubMed Central

    Keane, Terence M.; Rubin, Amy; Lachowicz, Mark; Brief, Deborah; Enggasser, Justin L.; Roy, Monica; Hermos, John; Helmuth, Eric; Rosenbloom, David

    2014-01-01

    The Diagnostic and Statistical Manual-5 (DSM-5) reformulated Posttraumatic Stress Disorder (PTSD) based partially on research showing there were four main factors that underlie the symptoms of the disorder. The primary aim of this study was to examine the temporal stability of the DSM-5 factors as measured by the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5; Weathers et al., 2010). Confirmatory factor analyses were conducted to examine the structure of DSM-5 PTSD, and temporal stability over three time points was examined to determine if the measure reflects a consistent construct over time. Our sample was 507 combat-exposed veterans of Iraq and Afghanistan who enrolled in an online intervention for problem drinking and combat-related stress (masked for review). We administered the PCL-5 at baseline, 8-week post intervention, and 3-month follow-up assessments. The DSM-5 model provided an adequate fit to the data at baseline. Tests of equality of form and equality of factor loadings demonstrated stability of the factor structure over time, indicating temporal stability. This study confirms the results of previous research supporting the DSM-5 model of PTSD symptoms (Elhai et al., 2012; Miller et al., 2012). This is the first study to demonstrate the temporal stability of the PCL-5, indicating its use in longitudinal studies will measure the same construct over time. PMID:24932642

  3. Risk factors for mental health problems in school-age children from a community sample.

    PubMed

    Mendes, Ana Vilela; Souza Crippa, José Alexandre de; Souza, Roberto Molina; Loureiro, Sonia Regina

    2013-12-01

    The epidemiological dimension of mental health problems in childhood and its impact warrant new studies. Knowledge about the predictors of mental health in children is scant in developing countries. The present study estimated the prevalence of psychiatric disorders in Brazilian school-age children based on a community sample from primary health care services, with the aim of verifying the predictive value of biological, social, and familial risk factors in children's mental health. The study was performed with 120 children of both genders identified through their mothers. The children's mental health was evaluated by sociodemographic factors and a diagnostic interview conducted with parents. Biological, social, and familial risk factors were evaluated by the Supplemental Questionnaire and Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. Of the 120 children, 45.8 % were diagnosed with at least one mental health disorder. Children with diagnoses of depressive disorder and generalized anxiety disorder presented evidence of greater exposure to risk factors compared with children without these psychiatric diagnoses. Children with more risk factors throughout their lifetime had greater comorbidities compared with children with a lower number of risk factors. The identification of groups exposed to interconnected risk factors represents a priority when planning mental health practices. The strong role of chronic familial risk factors needs to be emphasized because they are a possible target for the prevention of depressive and anxiety disorders. PMID:23212399

  4. Problems Accompanied Individuals with Learning Disability and Its Relationship to Gender and Family Economic Status Variables in a Jordanian Sample

    ERIC Educational Resources Information Center

    Al-Oweidi, Alia M.

    2015-01-01

    The purpose of this study is to investigate the relationship between problems that accompany individuals with learning disability and the variables of gender and family economic status for a selected sample of Jordanians. The sample of the study, which consisted of (239) male and female students, was chosen randomly. To achieve this aim, the…

  5. Quantification and molecular characterization of Salmonella isolated from food samples involved in salmonellosis outbreaks in Rio Grande do Sul, Brazil

    PubMed Central

    Mürmann, Lisandra; dos Santos, Maria Cecília; Longaray, Solange Mendes; Both, Jane Mari Corrêa; Cardoso, Marisa

    2008-01-01

    Data concerning the prevalence and populations of Salmonella in foods implicated in outbreaks may be important to the development of quantitative microbial risk assessments of individual food products. In this sense, the objective of the present study was to assess the amount of Salmonella sp. in different foods implicated in foodborne outbreaks in Rio Grande do Sul occurred in 2005 and to characterize the isolated strains using phenotypic and genotypic methods. Nineteen food samples involved in ten foodborne outbreaks occurred in 2005, and positive on Salmonella isolation at the Central Laboratory of the Health Department of the State of Rio Grande do Sul, were included in this study. Food samples were submitted to estimation of Salmonella using the Most Probable Number (MPN) technique. Moreover, one confirmed Salmonella colony of each food sample was serotyped, characterized by its XbaI-macrorestriction profile, and submitted to antimicrobial resistance testing. Foods containing eggs, mayonnaise or chicken were contaminated with Salmonella in eight outbreaks. Higher counts (>107 MPN.g-1) of Salmonella were detected mostly in foods containing mayonnaise. The isolation of Salmonella from multiple food items in five outbreaks probably resulted from the cross-contamination, and the high Salmonella counts detected in almost all analyzed samples probably resulted from storing in inadequate temperature. All strains were identified as S. Enteritidis, and presented a unique macrorestriction profile, demonstrating the predominance of one clonal group in foods involved in the salmonellosis outbreaks. A low frequency of antimicrobial resistant S. Enteritidis strains was observed and nalidixic acid was the only resistance marker detected. PMID:24031261

  6. The role of grandparents in preventing aggressive and other externalizing behavior problems in children from rural, methamphetamine-involved families

    PubMed Central

    Sheridan, Kathryn; Haight, Wendy L.; Cleeland, Leah

    2011-01-01

    Preventive interventions are urgently needed for children from rural, methamphetamine-involved families, who are at risk for the development of aggressive and other externalizing behavioral problems. This mixed method study explored naturally occurring sources of protection and considers the implications for targeted interventions. Participants were 41 children aged six to 14 years from rural families involved with methamphetamine and the public child welfare system, their primary caregivers, and 19 parents recovering from methamphetamine addiction. When invited during semi-structured interviews to talk about their families, 48% of children spontaneously described socially and emotionally supportive relationships with healthy grandparents. Children’s reports of support from grandparents were associated with lower scores on CBCL Social Problems, [t(37)= 2.23, p<.05 ]; externalizing behaviors, [t(37)= 2.07, p<.05]; and aggressive behaviors, [t(37)= 2.75, p<.01]. When asked to talk about their families, 58% of parents spontaneously described the support their children received from grandparents, and 26% also described the support that they had received from their own grandparents. Children’s and parents’ descriptions of grandparent support suggest how grandparents may protect children from the development of aggressive and other externalizing behavior problems. First, grandparents may prevent obstacles to healthy development by providing their grandchildren with safe shelter and basic child care when parents are incapacitated from substance misuse. Second, they may promote their grandchildren’s positive social-emotional development through supportive relationships. Third, they may promote social competence through enjoyable leisure activities with healthy adults and non-delinquent peers. Understanding naturally occurring sources of protection for children can inform the development of interventions by identifying strengths on which to build, and suggesting

  7. Gardner's Two Children Problems and Variations: Puzzles with Conditional Probability and Sample Spaces

    ERIC Educational Resources Information Center

    Taylor, Wendy; Stacey, Kaye

    2014-01-01

    This article presents "The Two Children Problem," published by Martin Gardner, who wrote a famous and widely-read math puzzle column in the magazine "Scientific American," and a problem presented by puzzler Gary Foshee. This paper explains the paradox of Problems 2 and 3 and many other variations of the theme. Then the authors…

  8. The Problem of Sample Contamination in a Fluvial Geochemistry Research Experience for Undergraduates.

    ERIC Educational Resources Information Center

    Andersen, Charles B.

    2001-01-01

    Introduces the analysis of a river as an excellent way to teach geochemical techniques because of the relative ease of sample collection and speed of sample analysis. Focuses on the potential sources of sample contamination during sampling, filtering, and bottle cleaning processes, and reviews methods to reduce and detect contamination. Includes…

  9. Initial impact of the Fast Track prevention trial for conduct problems: I. The high-risk sample. Conduct Problems Prevention Research Group.

    PubMed

    1999-10-01

    Fast Track is a multisite, multicomponent preventive intervention for young children at high risk for long-term antisocial behavior. Based on a comprehensive developmental model, intervention included a universal-level classroom program plus social skills training, academic tutoring, parent training, and home visiting to improve competencies and reduce problems in a high-risk group of children selected in kindergarten. At the end of Grade 1, there were moderate positive effects on children's social, emotional, and academic skills; peer interactions and social status; and conduct problems and special-education use. Parents reported less physical discipline and greater parenting satisfaction/ease of parenting and engaged in more appropriate/consistent discipline, warmth/positive involvement, and involvement with the school. Evidence of differential intervention effects across child gender, race, site, and cohort was minimal. PMID:10535230

  10. SIPPI: A Matlab toolbox for sampling the solution to inverse problems with complex prior information. Part 1—Methodology

    NASA Astrophysics Data System (ADS)

    Mejer Hansen, Thomas; Skou Cordua, Knud; Caroline Looms, Majken; Mosegaard, Klaus

    2013-03-01

    From a probabilistic point-of-view, the solution to an inverse problem can be seen as a combination of independent states of information quantified by probability density functions. Typically, these states of information are provided by a set of observed data and some a priori information on the solution. The combined states of information (i.e. the solution to the inverse problem) is a probability density function typically referred to as the a posteriori probability density function. We present a generic toolbox for Matlab and Gnu Octave called SIPPI that implements a number of methods for solving such probabilistically formulated inverse problems by sampling the a posteriori probability density function. In order to describe the a priori probability density function, we consider both simple Gaussian models and more complex (and realistic) a priori models based on higher order statistics. These a priori models can be used with both linear and non-linear inverse problems. For linear inverse Gaussian problems we make use of least-squares and kriging-based methods to describe the a posteriori probability density function directly. For general non-linear (i.e. non-Gaussian) inverse problems, we make use of the extended Metropolis algorithm to sample the a posteriori probability density function. Together with the extended Metropolis algorithm, we use sequential Gibbs sampling that allow computationally efficient sampling of complex a priori models. The toolbox can be applied to any inverse problem as long as a way of solving the forward problem is provided. Here we demonstrate the methods and algorithms available in SIPPI. An application of SIPPI, to a tomographic cross borehole inverse problems, is presented in a second part of this paper.

  11. Alcoholics Anonymous attendance following 12-step treatment participation as a link between alcohol-dependent fathers' treatment involvement and their children's externalizing problems.

    PubMed

    Andreas, Jasmina Burdzovic; O'Farrell, Timothy J

    2009-01-01

    We investigated longitudinal associations between alcohol-dependent fathers' 12-step treatment involvement and their children's internalizing and externalizing problems (N = 125, M(age) = 9.8 +/- 3.1), testing the hypotheses that fathers' greater treatment involvement would benefit later child behavior and that this effect would be mediated by fathers' posttreatment behaviors. The initial association was established between fathers' treatment involvement and children's externalizing problems only, whereas Structural Equation Modeling (SEM) results supported mediating hypotheses. Fathers' greater treatment involvement predicted children's lower externalizing problems 12 months later, and fathers' posttreatment behaviors mediated this association: Greater treatment involvement predicted greater posttreatment Alcoholics Anonymous attendance, which in turn predicted greater abstinence. Finally, fathers' abstinence was associated with lower externalizing problems in children. Theoretical and practical implications of these findings are discussed. PMID:18715745

  12. An Investigation of Eighth Grade Students' Problem Posing Skills (Turkey Sample)

    ERIC Educational Resources Information Center

    Arikan, Elif Esra; Ünal, Hasan

    2015-01-01

    To pose a problem refers to the creative activity for mathematics education. The purpose of the study was to explore the eighth grade students' problem posing ability. Three learning domains such as requiring four operations, fractions and geometry were chosen for this reason. There were two classes which were coded as class A and class B. Class A…

  13. An Investigation of Eighth Grade Students' Problem Posing Skills (Turkey Sample)

    ERIC Educational Resources Information Center

    Arikan, Elif Esra; Ünal, Hasan

    2015-01-01

    To pose a problem refers to the creative activity for mathematics education. The purpose of the study was to explore the eighth grade students' problem posing ability. Three learning domains such as requiring four operations, fractions and geometry were chosen for this reason. There were two classes which were coded as class A and class B.…

  14. Etiologies of Associations between Childhood Sleep and Behavioral Problems in a Large Twin Sample.

    ERIC Educational Resources Information Center

    Gregory, Alice M.; Eley, Thalia C.; O'Connor, Thomas G.; Plomin, Robert

    2004-01-01

    Objective: To examine the etiologies of covariation of childhood sleep problems and other behavioral/emotional problems in young children. Method: The parents of more than 6,000 twin pairs provided information on their twins' anxiety, conduct, and hyperactivity at ages 3, 4, and 7 by completing the Strengths and Difficulties Questionnaire.…

  15. Testing Jessor's problem behavior theory and syndrome: a nationally representative comparative sample of Latino and African American adolescents.

    PubMed

    Mobley, Michael; Chun, Heejung

    2013-04-01

    Based on Jessor's problem behavior theory (PBT; R. Jessor, 1987, Problem-behavior theory, psychosocial development, and adolescent problem drinking, British Journal of Addiction, Vol. 82, pp. 331-342), the comparability of a second-order problem behavior model (SPBM) was investigated employing structural equation modeling (SEM) and latent mean differences in problem behavior engagement were examined among racial/ethnic adolescents. Within a span of nearly 25 years, this study represents the first nationally representative sample of Latino and African American adolescents utilized in testing Jessor's PBT and problem behavior syndrome (PBS). Using a sample of 5,831 Latino, African American, and European American adolescents drawn from the National Longitudinal Study of Adolescent Health, a series of invariance tests evidenced support for Jessor's PBT and PBS. Latent mean difference test results evidenced significant differences in problem behaviors (e.g., academic failure [AF], aggression [AG], substance use [SU], and risky sexual activity[RSA]) across racial/ethnic adolescent groups, which could be explained partially by PBS. A discussion of findings, limitations, and recommendations for future research is presented. PMID:23647329

  16. Examining the psychometric properties of the Barratt Impulsiveness Scale-Brief Form in justice-involved samples.

    PubMed

    Fields, Sherecce; Edens, John F; Smith, Shannon Toney; Rulseh, Allison; Donnellan, M Brent; Ruiz, Mark A; McDermott, Barbara E; Douglas, Kevin S

    2015-12-01

    Impulsivity is an important component of many forms of psychopathology. Though widely used as an index of this construct, the 30-item Barratt Impulsiveness Scale-11 (BIS-11) has demonstrated questionable psychometric properties in several research reports. An 8-item shortened version has recently been proposed, the Barratt Impulsiveness Scale-Brief (BIS-Brief) form, which was designed to overcome some of the limitations of the longer scale. In this report, we examine the internal structure and theoretically relevant external correlates of this new short form in large archival samples of individuals involved in the criminal justice system (prison inmates, substance abusers in mandatory treatment, and forensic inpatients). Confirmatory factor analysis of the BIS-Brief indicates adequate fit following a relatively minor modification. Correlations between the BIS-Brief and an array of criterion measures-other self-report scales, interview-based measures, and behavioral outcomes-are consistent with predictions and show relatively little or no decrement in predictive validity when compared with the 30-item BIS-11. Our results suggest that the BIS-Brief is a promising brief measure of impulsivity that evinces good psychometric properties across a range of offender samples. PMID:25894703

  17. Application of the Tripartite Model to a Complicated Sample of Residential Youth with Externalizing Problems

    ERIC Educational Resources Information Center

    Chin, Eu Gene; Ebesutani, Chad; Young, John

    2013-01-01

    The tripartite model of anxiety and depression has received strong support among child and adolescent populations. Clinical samples of children and adolescents in these studies, however, have usually been referred for treatment of anxiety and depression. This study investigated the fit of the tripartite model with a complicated sample of…

  18. Investigation of Problem Solving Ability of Students in School of Physical Education and Sports (Kafkas University Sample)

    ERIC Educational Resources Information Center

    Ozmutlu, Ilker

    2014-01-01

    The aim of this research is to examine the problem solving abilities of School of Physical Education and Sports students. To achieve this aim, in the academic year 2013-2014, a research group did a study of 433 students of the School of Physical Education and Sports, Kafkas University. This sample consisted of 184 female and 249 male students.…

  19. ADHD Symptoms and Peer Relations of Children in a Community Sample: Examining Associated Problems, Self-Perceptions, and Gender Differences

    ERIC Educational Resources Information Center

    Diamantopoulou, Sofia; Henricsson, Lisbeth; Rydell, Ann-Margret

    2005-01-01

    This study examined children's peer relations in relation to gender, symptoms of attention-deficit/hyperactivity disorder (ADHD), associated behaviour problems, prosociality, and self-perceptions, in a community sample. Six hundred and thirty-five 12-year-old children (314 girls) provided peer nominations and rated feelings of loneliness and…

  20. Adolescent Psychological Health Problems and Delinquency among Volatile Substance Users in a School Sample in South London

    ERIC Educational Resources Information Center

    Best, David; Manning, Victoria; Gossop, Michael; Witton, John; Floyd, Karen; Rawaf, Salman; Strang, John

    2004-01-01

    The study assessed prevalence of volatile substance abuse (VSA), and its link to other forms of psychoactive substance use and to other problem behaviours among 14-15 year olds recruited from sixteen secondary schools in south-west London. Lifetime use of volatile substances was reported by 126 young people (6% of the sample) whose mean age of…

  1. Ten-Year Comparisons of Problems and Competencies for National Samples of Youth: Self, Parent, and Teacher Reports.

    ERIC Educational Resources Information Center

    Achenbach, Thomas M.; Dumenci, Levent; Rescorla, Leslie A.

    2002-01-01

    This study compared national samples of United States' 11- to 18- year-olds assessed in 1989 and 1999. Parent, teacher and self-report sources showed small improvements in competencies and adaptive functioning and small declines in problems over ten years. No significant differences on any scales were found for youths assessed shortly before and…

  2. Residue variability and sampling--practical problems and consequences for residues monitoring.

    PubMed

    Hill, A R

    2000-07-01

    Data generated in the UK have indicated that pesticide residue levels can be highly variable between the individual fruit or vegetables from the same crop or lot in trade. Statistical experiments with these data showed that residues in composite samples, taken according to Codex recommendations, are unlikely to differ by more than a factor of 3-4 from the mean level in the lot. This was corroborated by results obtained from real composite samples. Many fruit or vegetables in trade are mixed after harvest to form combined lots. Analysis of composite samples provides a good indication of average residues but, where the lot has been mixed, such average values are potentially misleading. Residues monitoring is the best means available for general control of pesticide use and consumer exposure, but new strategies for sampling and analysis are required to address the combined effects of residues variability and mixing of lots. PMID:10983575

  3. Enhance Low-Achieving Students' Learning Involvement in Taiwan's Higher Education: An Approach via E-Learning with Problem-Based Learning and Self-Regulated Learning

    ERIC Educational Resources Information Center

    Lee, Tsang-Hsiung; Shen, Pei-Di; Tsai, Chia-Wen

    2010-01-01

    This study explored the effects of web-enabled pedagogies on students' involvement in learning. A series of quasi-experiments were conducted to investigate whether students' involvement increases over time if intervened, respectively, by problem-based learning (PBL), self-regulated learning (SRL), and their combinations. Two classes of 102…

  4. Variants of Callous-Unemotional Conduct Problems in a Community Sample of Adolescents

    ERIC Educational Resources Information Center

    Fanti, Kostas A.; Demetriou, Chara A.; Kimonis, Eva R.

    2013-01-01

    Callous-unemotional traits are believed to be a childhood precursor to psychopathy, and among youth with conduct problems they designate those showing a particularly severe, stable, and aggressive pattern of antisocial behavior. Youth with callous-unemotional traits are a heterogeneous population and, analogous to adults with psychopathy, research…

  5. Problems of Definition in Sampling Special Populations: The Case of Homeless Persons.

    ERIC Educational Resources Information Center

    Johnson, Timothy P.; And Others

    1993-01-01

    Problems of definition in estimation in evaluation research were studied through a survey of homeless persons in Cook County (Illinois) based on 481 interviews. Differences arising from the following four population definitions are presented: (1) traditional homeless; (2) marginally housed; (3) social isolates; and (4) total of these categories.…

  6. Eating Problems at Age 6 Years in a Whole Population Sample of Extremely Preterm Children

    ERIC Educational Resources Information Center

    Samara, Muthanna; Johnson, Samantha; Lamberts, Koen; Marlow, Neil; Wolke, Dieter

    2010-01-01

    Aim: The aim of this study was to investigate the prevalence of eating problems and their association with neurological and behavioural disabilities and growth among children born extremely preterm (EPC) at age 6 years. Method: A standard questionnaire about eating was completed by parents of 223 children (125 males [56.1%], 98 females [43.9%])…

  7. Problems with sampling desert tortoises: A simulation analysis based on field data

    USGS Publications Warehouse

    Freilich, J.E.; Camp, R.J.; Duda, J.J.; Karl, A.E.

    2005-01-01

    The desert tortoise (Gopherus agassizii) was listed as a U.S. threatened species in 1990 based largely on population declines inferred from mark-recapture surveys of 2.59-km2 (1-mi2) plots. Since then, several census methods have been proposed and tested, but all methods still pose logistical or statistical difficulties. We conducted computer simulations using actual tortoise location data from 2 1-mi2 plot surveys in southern California, USA, to identify strengths and weaknesses of current sampling strategies. We considered tortoise population estimates based on these plots as "truth" and then tested various sampling methods based on sampling smaller plots or transect lines passing through the mile squares. Data were analyzed using Schnabel's mark-recapture estimate and program CAPTURE. Experimental subsampling with replacement of the 1-mi2 data using 1-km2 and 0.25-km2 plot boundaries produced data sets of smaller plot sizes, which we compared to estimates from the 1-mi 2 plots. We also tested distance sampling by saturating a 1-mi 2 site with computer simulated transect lines, once again evaluating bias in density estimates. Subsampling estimates from 1-km2 plots did not differ significantly from the estimates derived at 1-mi2. The 0.25-km2 subsamples significantly overestimated population sizes, chiefly because too few recaptures were made. Distance sampling simulations were biased 80% of the time and had high coefficient of variation to density ratios. Furthermore, a prospective power analysis suggested limited ability to detect population declines as high as 50%. We concluded that poor performance and bias of both sampling procedures was driven by insufficient sample size, suggesting that all efforts must be directed to increasing numbers found in order to produce reliable results. Our results suggest that present methods may not be capable of accurately estimating desert tortoise populations.

  8. Target problem (mis) matching: predictors and consequences of parent-youth agreement in a sample of anxious youth.

    PubMed

    Hoffman, Lauren J; Chu, Brian C

    2015-04-01

    Parents and youth often report discrepant target problems upon seeking treatment for youth psychopathology, which can have important impact on therapy processes (e.g., dropout) and treatment outcomes, as entry-level attitudes have been found to be influential in ultimate use and benefit of treatment. The current study examined parent-youth agreement within an anxiety disordered sample by assessing demographic and diagnostic factors that may predict matching, as well as the impact of matching on attrition, treatment outcome, and parental satisfaction. Ninety-five youth with principal anxiety disorders received cognitive-behavioral treatment for anxiety at a university outpatient clinic. Youth and parents independently identified target problems during the pretreatment assessment. Target problems were coded into 25 qualitative categories representing diagnostic, symptom, and functional impairment domains, including diffuse anxiety, social anxiety, academic achievement, oppositional/behavior problems, sleep problems, suicidal ideation, and family functioning. The majority of parent-youth dyads (67.4%) agreed on at least one target problem. Although problems related to diffuse anxiety and social anxiety were reported most frequently, relatively low rates of agreement were found in these domains. Kappa values demonstrated higher levels of agreement for problems with specific fears, school attendance, and panic and lower levels of agreement for difficulties with worry, shame, and self-esteem. Further, youth diagnosed with comorbid externalizing disorders were less likely to agree with their parents on at least one target problem. No effects were found for gender, age, or number of diagnoses in predicting agreement. Target problem agreement did not significantly impact rates of attrition or diagnostic remission, but did predict some measures of parental satisfaction. Results suggest that disagreement on treatment goals exists even within a narrow treatment population and

  9. Initial Impact of the Fast Track Prevention Trial for Conduct Problems: I. The High-Risk Sample

    PubMed Central

    2009-01-01

    Fast Track is a multisite, multicomponent preventive intervention for young children at high risk for long-term antisocial behavior. Based on a comprehensive developmental model intervention included a universal-level classroom program plus social skills training, academic tutoring, parent training, and home visiting to improve competencies and reduce problems in a high-risk group of children selected in kindergarten. At the end of Grade 1, there were moderate positive effects on children's social, emotional, and academic skills; peer interactions and social status; and conduct problems and special-education use. Parents reported less-physical discipline and greater parenting satisfaction/ease of parenting and engaged in more appropriate/consistent discipline, warmth/positive involvement, and involvement with the school. Evidence of differential intervention effects across child gender, race, site, and cohort was minimal. PMID:10535230

  10. Acute health problems among subjects involved in the cleanup operation following the Prestige oil spill in Asturias and Cantabria (Spain).

    PubMed

    Suárez, B; Lope, V; Pérez-Gómez, B; Aragonés, N; Rodríguez-Artalejo, F; Marqués, F; Guzmán, A; Viloria, L J; Carrasco, J M; Martín-Moreno, J M; López-Abente, G; Pollán, M

    2005-11-01

    The purpose of this study was to evaluate exposure conditions and acute health effects in subjects participating in the Prestige oil spill cleanup activities and the association between these and the nature of the work and use of protection devices in the regions of Asturias and Cantabria (Spain). The sample comprised 400 subjects in each region, selected from a random sampling of all persons involved in cleanup activities, stratified by type of worker and number of working days. Data were obtained via a structured questionnaire and included information on specific tasks, number of working days, use of protective materials, and acute health effects. These effects were classified into two broad groups: injuries and toxic effects. Data analysis was performed using complex survey methods. Significant differences between groups were evaluated using Pearson's chi(2) test. Unconditional logistic regression was used to compute odds ratios and 95% confidence intervals. Bird cleaners accounted for the highest prevalence of injuries (19% presented with lesions). Working more than 20 days in highly polluted areas was associated with increased risk of injury in all workers. Occurrence of toxic effects was higher among seamen, possibly due to higher exposure to fuel oil and its components. Toxic effects were more frequent among those working longer than 20 days in highly polluted areas, performing three or more different cleaning activities, having skin contact with fuel oil on head/neck or upper limbs, and eating while in contact with fuel or perceiving disturbing odors. No severe disorders were identified among individuals who performed these tasks. However, potential health impact should be considered when organizing cleanup activities in similar environmental disasters. PMID:16307984

  11. Problems Found Using a Radon Stripping Algorithm for Retrospective Assessment of Air Filter Samples

    SciTech Connect

    Robert Hayes

    2008-04-01

    An evaluation of a large number of air sample filters was undertaken using a commercial alpha and beta spectroscopy system employing a passive implanted planar silicon (PIPS) detector. Samples were only measured after air flow through the filters had ceased. Use of a commercial radon stripping algorithm was implemented to discriminate anthropogenic alpha activity on the filters from the radon progeny. When uncontaminated air filters were evaluated, the results showed that there was a time-dependent bias in both average estimates and measurement dispersion of anthropogenic activity estimates with the relative bias being small compared to the dispersion, indicating that the system would not give false positive indications for an appropriately set decision level. By also measuring environmental air sample filters simultaneously with electroplated alpha filters, use of the radon stripping algorithm demonstrated a number of substantial unexpected deviations from calibrated values indicating that the system would give false negative indications. Use of the current algorithm is, therefore, not recommended for general assay applications. Use of the PIPS detector should only be utilized for gross counting without appropriate modifications to the curve-fitting algorithm. As a screening method, the radon stripping algorithm might be expected to see elevated alpha activities on air sample filters (not due to radon progeny) around the 200 disintegrations per minute level.

  12. Analysing Cognitive or Non-Cognitive Factors Involved in the Process of Physics Problem-Solving in an Everyday Context

    ERIC Educational Resources Information Center

    Park, Jongwon; Lee, Limook

    2004-01-01

    Recently, the importance of an everyday context in physics learning, teaching, and problem-solving has been emphasized. However, do students or physics educators really want to learn or teach physics problem-solving in an everyday context? Are there not any obstructive factors to be considered in solving the everyday context physics problems? To…

  13. Problems Involved in an Emergency Method of Guiding a Gliding Vehicle from High Altitudes to a High Key Position

    NASA Technical Reports Server (NTRS)

    Jewel, Joseph W., Jr.; Whitten, James B.

    1960-01-01

    An investigation has been conducted to determine the problems involved in an emergency method of guiding a gliding vehicle from high altitudes to a high key position (initial position) above a landing field. A jet airplane in a simulated flameout condition, conventional ground-tracking radar, and a scaled wire for guidance programming on the radar plotting board were used in the tests. Starting test altitudes varied from 30,000 feet to 46,500 feet, and starting positions ranged 8.4 to 67 nautical miles from the high key. Specified altitudes of the high key were 12,000, 10,000 or 4,000 feet. Lift-drag ratios of the aircraft of either 17, 16, or 6 were held constant during any given flight; however, for a few flights the lift-drag ratio was varied from 11 to 6. Indicated airspeeds were held constant at either 160 or 250 knots. Results from these tests indicate that a gliding vehicle having a lift-drag ratio of 16 and an indicated approach speed of 160 knots can be guided to within 800 feet vertically and 2,400 feet laterally of a high key position. When the lift-drag ratio of the vehicle is reduced to 6 and the indicated approach speed is raised to 250 knots, the radar controller was able to guide the vehicle to within 2,400 feet vertically and au feet laterally of the high key. It was also found that radar stations which give only azimuth-distance information could control the glide path of a gliding vehicle as well as stations that receive azimuth-distance-altitude information, provided that altitude information is supplied by the pilot.

  14. Interrelationships between LGBT-based victimization, suicide, and substance use problems in a diverse sample of sexual and gender minorities.

    PubMed

    Mereish, Ethan H; O'Cleirigh, Conall; Bradford, Judith B

    2014-01-01

    Research has documented significant relationships between sexual and gender minority stress and higher rates of suicidality (i.e. suicidal ideation and attempts) and substance use problems. We examined the potential mediating role of substance use problems on the relationship between sexual and gender minority stress (i.e. victimization based on lesbian, gay, bisexual, or transgender identity [LGBT]) and suicidality. A nonprobability sample of LGBT patients from a community health center (N = 1457) ranged in age from 19-70 years. Participants reported history of lifetime suicidal ideation and attempts, substance use problems, as well as experiences of LGBT-based verbal and physical attacks. Substance use problems were a significant partial mediator between LGBT-based victimization and suicidal ideation and between LGBT-based victimization and suicide attempts for sexual and gender minorities. Nuanced gender differences revealed that substance use problems did not significantly mediate the relationship between victimization and suicide attempts for sexual minority men. Substance use problems may be one insidious pathway that partially mediates the risk effects of sexual and gender minority stress on suicidality. Substances might be a temporary and deleterious coping resource in response to LGBT-based victimization, which have serious effects on suicidal ideation and behaviors. PMID:23535038

  15. Aggressive Behavior Problems in Children with Autism Spectrum Disorders: Prevalence and Correlates in a Large Clinical Sample

    PubMed Central

    Hill, Alison Presmanes; Zuckerman, Katharine E.; Hagen, Arlene D.; Kriz, Daniel J.; Duvall, Susanne W.; van Santen, Jan; Nigg, Joel; Fair, Damien; Fombonne, Eric

    2014-01-01

    Aggressive behavior problems (ABP) are frequent yet poorly understood in children with Autism Spectrum Disorders (ASD) and are likely to co-vary significantly with comorbid problems. We examined the prevalence and sociodemographic correlates of ABP in a clinical sample of children with ASD (N = 400; 2–16.9 years). We also investigated whether children with ABP experience more intensive medical interventions, greater impairments in behavioral functioning, and more severe comorbid problems than children with ASD who do not have ABP. One in four children with ASD had Child Behavior Checklist scores on the Aggressive Behavior scale in the clinical range (T-scores ≥ 70). Sociodemographic factors (age, gender, parent education, race, ethnicity) were unrelated to ABP status. The presence of ABP was significantly associated with increased use of psychotropic drugs and melatonin, lower cognitive functioning, lower ASD severity, and greater comorbid sleep, internalizing, and attention problems. In multivariate models, sleep, internalizing, and attention problems were most strongly associated with ABP. These comorbid problems may hold promise as targets for treatment to decrease aggressive behavior and proactively identify high-risk profiles for prevention. PMID:25221619

  16. Pretreatment of plant and soil samples: a problem in boron analysis. Part I. Plants

    SciTech Connect

    Wikner, B.

    1986-01-01

    Possible sources of errors in the determination of boron in plant samples were examined. During drying and grinding neither loss nor contamination of boron was observed. It was found that boron was slightly lost when muffling at temperatures higher than 550/sup 0/C. The addition of Ca(OH)/sub 2/ prevented the loss but gave rise to incomplete ashing in many cases. Nitrate salts added in order to enhance oxidation gave rise to boron loss. Wet ashing should be done preferably in a concentrated sulfuric acid or phosphoric acid medium at low temperatures. At higher temperatures the shape of the digestion flask is important - long neck flasks are usually safe enough due to their condensating effects. Very high temperatures with foaming demand additional cooling condensors. Borosilicate glass can not be used. Extraction of plant samples with hydrochloric acid is a convenient alternative but no more than 75-94% of the total boron concentration in plants could be extracted.

  17. Problems associated with using filtration to define dissolved trace element concentrations in natural water samples

    USGS Publications Warehouse

    Horowitz, A.J.; Lum, K.R.; Garbarino, J.R.; Hall, G.E.M.; Lemieux, C.; Demas, C.R.

    1996-01-01

    Field and laboratory experiments indicate that a number of factors associated with filtration other than just pore size (e.g., diameter, manufacturer, volume of sample processed, amount of suspended sediment in the sample) can produce significant variations in the 'dissolved' concentrations of such elements as Fe, Al, Cu, Zn, Pb, Co, and Ni. The bulk of these variations result from the inclusion/exclusion of colloidally associated trace elements in the filtrate, although dilution and sorption/desorption from filters also may be factors. Thus, dissolved trace element concentrations quantitated by analyzing filtrates generated by processing whole water through similar pore-sized filters may not be equal or comparable. As such, simple filtration of unspecified volumes of natural water through unspecified 0.45-??m membrane filters may no longer represent an acceptable operational definition for a number of dissolved chemical constituents.

  18. Pathways to Vulnerability for Alcohol Problem Severity in a Treatment-Seeking Sample

    PubMed Central

    Eddie, David; Epstein, Elizabeth E.; Cohn, Amy M.

    2014-01-01

    Objectives The present investigation examined the role of gender, family history of alcohol and drug use disorders, temperament, childhood behavior problems, and adult psychopathology, on adult alcohol use disorder (AUD) severity. Methods Structural equation modeling was used to examine multiple etiological pathways to adult alcohol use disorder (AUD) severity. Participants included 335 treatment-seeking males and females with current or lifetime DSM-III-R alcohol dependence (96%) or abuse (4%) enrolled in one of five treatment outcome studies. Extensive assessment at treatment entry used a mixture of retrospective and current self-report. Results Results identified two significant paths associated with a latent factor of adult alcohol use disorder severity at entry to treatment. In Path 1, male gender and family history of drug use disorder predicted greater childhood behavior problems, which predicted antisocial personality disorder (ASPD), borderline personality disorder (BPD), and anxiety disorders (ADs), with anxiety disorders leading directly to alcohol use disorder severity. In Path 2, family history of alcohol use disorder predicted difficult temperament in childhood, which predicted borderline personality disorder, major depressive disorder (MDD) and anxiety disorders; both major depressive disorder and anxiety disorders in turn predicted alcohol use disorder severity at treatment entry. Conclusions The present findings build on the literature on heterogeneity in developmental risk processes leading to the expression of adult alcohol use disorder symptomology among patients presenting for alcohol use disorder treatment. PMID:26170766

  19. Frontal–Parietal and Limbic-Striatal Activity Underlies Information Sampling in the Best Choice Problem

    PubMed Central

    Costa, Vincent D.; Averbeck, Bruno B.

    2015-01-01

    Best choice problems have a long mathematical history, but their neural underpinnings remain unknown. Best choice tasks are optimal stopping problem that require subjects to view a list of options one at a time and decide whether to take or decline each option. The goal is to find a high ranking option in the list, under the restriction that declined options cannot be chosen in the future. Conceptually, the decision to take or decline an option is related to threshold crossing in drift diffusion models, when this process is thought of as a value comparison. We studied this task in healthy volunteers using fMRI, and used a Markov decision process to quantify the value of continuing to search versus committing to the current option. Decisions to take versus decline an option engaged parietal and dorsolateral prefrontal cortices, as well ventral striatum, anterior insula, and anterior cingulate. Therefore, brain regions previously implicated in evidence integration and reward representation encode threshold crossings that trigger decisions to commit to a choice. PMID:24142842

  20. Calculation of sample problems related to two-phase flow blowdown transients in pressure relief piping of a PWR pressurizer

    SciTech Connect

    Shin, Y.W.; Wiedermann, A.H.

    1984-02-01

    A method was published, based on the integral method of characteristics, by which the junction and boundary conditions needed in computation of a flow in a piping network can be accurately formulated. The method for the junction and boundary conditions formulation together with the two-step Lax-Wendroff scheme are used in a computer program; the program in turn, is used here in calculating sample problems related to the blowdown transient of a two-phase flow in the piping network downstream of a PWR pressurizer. Independent, nearly exact analytical solutions also are obtained for the sample problems. Comparison of the results obtained by the hybrid numerical technique with the analytical solutions showed generally good agreement. The good numerical accuracy shown by the results of our scheme suggest that the hybrid numerical technique is suitable for both benchmark and design calculations of PWR pressurizer blowdown transients.

  1. The association of ADHD and depression: Mediation by peer problems and parent-child difficulties in two complementary samples

    PubMed Central

    Humphreys, Kathryn L.; Katz, Shaina J.; Lee, Steve S.; Hammen, Constance L.; Brennan, Patricia A.; Najman, Jake M.

    2013-01-01

    Children with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for the development of depression, with evidence that peer and academic difficulties mediate predictions of later depression from ADHD. The present study hypothesized that parent-child relationship difficulties may be an additional potential mediator of this association. Academic, peer, and parent-child functioning were tested as mediators of the association of attention problems and depression in two distinctly different, yet complementary samples. Study 1 was a cross-sectional sample of 230 5–10 year-old children with and without ADHD. Study 2 was a prospective longitudinal sample of 472 youth followed prospectively from birth to age 20 at risk for depression. Despite differences in age, measures, and designs, both studies implicated peer and parent-child problems as unique mediators of depressive symptoms, although academic difficulties did not uniquely mediate the ADHD-depression association. Further, inattention symptoms, but not hyperactivity, predicted depressive symptoms via the disruption of interpersonal functioning. The inclusion of oppositional defiant disorder into models impacted results, and supported its independent role in parent-child problems. Implications include support for interventions that target interpersonal competence, which may effectively reduce the risk of depression among children with ADHD. PMID:24016021

  2. Biased sampling of methane release from northern lakes: A problem for extrapolation

    NASA Astrophysics Data System (ADS)

    Wik, Martin; Thornton, Brett F.; Bastviken, David; Uhlbäck, Jo; Crill, Patrick M.

    2016-02-01

    Methane emissions from lakes are widely thought to be highly irregular and difficult to quantify with anything other than numerous distributed measurement stations and long-term sampling campaigns. In spite of this, a large majority of the study sites north of 50°N have been measured over surprisingly short time periods of only one to a few days. Using long-term data from three intensively studied small subarctic lakes, we recommend that measurements of diffusive methane flux and ebullition should be made over at least 11 and 39 days scattered throughout the ice-free season using depth-stratified sampling at 3 and 11 or more locations, respectively. We further show that low temporal and spatial resolutions are unlikely to cause overestimates. Therefore, we argue that most sites measured previously are likely underestimated in terms of emission potential. Avoiding these biases seen in much of the contemporary data is crucial to further constrain large-scale methane emissions from northern lakes and ponds.

  3. Iterative method for the numerical prediction of heat transfer in problems involving large differences in thermal conductivities

    SciTech Connect

    Kelkar, K.M. )

    1990-01-01

    Heat exchange that occurs between materials with largely differing thermal conductivities is commonly encountered in engineering practice.Conventional iterative solution methods perform poorly for the numerical solution for such problems. Results for computations for test problems indicate that the proposed solution procedure enables efficient solution of heat transfer problems with large conductivity differences for which the conventional line-by-line method proves ineffective.

  4. The Role of Religious Coping Strategies in Predicting Depression among a Sample of Women with Fertility Problems in Shiraz

    PubMed Central

    Aflakseir, Abdulaziz; Mahdiyar, Mansoureh

    2016-01-01

    Background: One of the most common mental health problems among women with infertility problems is depression. Research has shown that religious beliefs and practices can help people to cope with difficult situations. The purpose of this study was to explore the role of different religious coping strategies in predicting depression in a group of infertile women in Shiraz. Methods: A total of 72 women with fertility problems were recruited from several private infertility clinics in Shiraz using convenience sampling. The participants completed the research questionnaires including Beck Depression Inventory and Religious Coping Scale. The Religious Coping Scale consists of five dimensions including practice, active, passive, benevolent reappraisal and negative religious coping. Descriptive statistics (frequency percentage, mean and standard deviation), Pearson’s correlation and simultaneous multiple regression analysis were used for data analysis using SPSS version 16. A p-value less than 0.05 was considered statistically significant. Results: The present study showed that about 30% of women with fertility problems experienced the symptoms of depression. The findings also indicated that the most commonly used religious coping strategy was practice religious coping, while the least commonly used religious coping strategies were passive and negative religious coping. The findings also showed that active religious coping, practice religious coping and benevolent reappraisal coping predicted depression reduction. Conclusion: This study highlights the effect of religious coping on depression reduction of women with fertility problems. In other words, women who used religious coping strategies were less likely to experience depression symptoms. PMID:27141467

  5. The k-sample problem in a multi-state model and testing transition probability matrices.

    PubMed

    Tattar, Prabhanjan N; Vaman, H J

    2014-07-01

    The choice of multi-state models is natural in analysis of survival data, e.g., when the subjects in a study pass through different states like 'healthy', 'in a state of remission', 'relapse' or 'dead' in a health related quality of life study. Competing risks is another common instance of the use of multi-state models. Statistical inference for such event history data can be carried out by assuming a stochastic process model. Under such a setting, comparison of the event history data generated by two different treatments calls for testing equality of the corresponding transition probability matrices. The present paper proposes solution to this class of problems by assuming a non-homogeneous Markov process to describe the transitions among the health states. A class of test statistics are derived for comparison of [Formula: see text] treatments by using a 'weight process'. This class, in particular, yields generalisations of the log-rank, Gehan, Peto-Peto and Harrington-Fleming tests. For an intrinsic comparison of the treatments, the 'leave-one-out' jackknife method is employed for identifying influential observations. The proposed methods are then used to develop the Kolmogorov-Smirnov type supremum tests corresponding to the various extended tests. To demonstrate the usefulness of the test procedures developed, a simulation study was carried out and an application to the Trial V data provided by International Breast Cancer Study Group is discussed. PMID:23722306

  6. The Role of Parenting in the Prediction of Criminal Involvement: Findings from a Nationally Representative Sample of Youth and a Sample of Adopted Youth

    ERIC Educational Resources Information Center

    Beaver, Kevin M.; Schwartz, Joseph A.; Connolly, Eric J.; Al-Ghamdi, Mohammed Said; Kobeisy, Ahmed Nezar

    2015-01-01

    The role of parenting in the development of criminal behavior has been the source of a vast amount of research, with the majority of studies detecting statistically significant associations between dimensions of parenting and measures of criminal involvement. An emerging group of scholars, however, has drawn attention to the methodological…

  7. Learning by Reading: Description of Learning Strategies of Students Involved in a Problem-Based Learning Program.

    ERIC Educational Resources Information Center

    Cartier, Sylvie; Plante, Andre; Tardif, Jacques

    Many educational institutions have moved toward situated learning and problem-based learning (PBL) in which students, to learn, must rely on investigations of problems within an authentic professional context. A study examined and described how students read and learn in such a context. Results of a 1995 qualitative study showed that four out of…

  8. Hyperbolic heat conduction problems involving non-Fourier effects - Numerical simulations via explicit Lax-Wendroff/Taylor-Galerkin finite element formulations

    NASA Technical Reports Server (NTRS)

    Tamma, Kumar K.; Namburu, Raju R.

    1989-01-01

    Numerical simulations are presented for hyperbolic heat-conduction problems that involve non-Fourier effects, using explicit, Lax-Wendroff/Taylor-Galerkin FEM formulations as the principal computational tool. Also employed are smoothing techniques which stabilize the numerical noise and accurately predict the propagating thermal disturbances. The accurate capture of propagating thermal disturbances at characteristic time-step values is achieved; numerical test cases are presented which validate the proposed hyperbolic heat-conduction problem concepts.

  9. Exploring equivalence domain in nonlinear inverse problems using Covariance Matrix Adaption Evolution Strategy (CMAES) and random sampling

    NASA Astrophysics Data System (ADS)

    Grayver, Alexander V.; Kuvshinov, Alexey V.

    2016-05-01

    This paper presents a methodology to sample equivalence domain (ED) in nonlinear partial differential equation (PDE)-constrained inverse problems. For this purpose, we first applied state-of-the-art stochastic optimization algorithm called Covariance Matrix Adaptation Evolution Strategy (CMAES) to identify low-misfit regions of the model space. These regions were then randomly sampled to create an ensemble of equivalent models and quantify uncertainty. CMAES is aimed at exploring model space globally and is robust on very ill-conditioned problems. We show that the number of iterations required to converge grows at a moderate rate with respect to number of unknowns and the algorithm is embarrassingly parallel. We formulated the problem by using the generalized Gaussian distribution. This enabled us to seamlessly use arbitrary norms for residual and regularization terms. We show that various regularization norms facilitate studying different classes of equivalent solutions. We further show how performance of the standard Metropolis-Hastings Markov chain Monte Carlo algorithm can be substantially improved by using information CMAES provides. This methodology was tested by using individual and joint inversions of magneotelluric, controlled-source electromagnetic (EM) and global EM induction data.

  10. Exploring equivalence domain in non-linear inverse problems using Covariance Matrix Adaption Evolution Strategy (CMAES) and random sampling

    NASA Astrophysics Data System (ADS)

    Grayver, Alexander V.; Kuvshinov, Alexey V.

    2016-02-01

    This paper presents a methodology to sample equivalence domain (ED) in non-linear PDE-constrained inverse problems. For this purpose, we first applied state-of-the-art stochastic optimization algorithm called Covariance Matrix Adaptation Evolution Strategy (CMAES) to identify low misfit regions of the model space. These regions were then randomly sampled to create an ensemble of equivalent models and quantify uncertainty. CMAES is aimed at exploring model space globally and is robust on very ill-conditioned problems. We show that the number of iterations required to converge grows at a moderate rate with respect to number of unknowns and the algorithm is embarrassingly parallel. We formulated the problem by using the generalized Gaussian distribution. This enabled us to seamlessly use arbitrary norms for residual and regularization terms. We show that various regularization norms facilitate studying different classes of equivalent solutions. We further show how performance of the standard Metropolis-Hastings Markov chain Monte Carlo (MCMC) algorithm can be substantially improved by using information CMAES provides. This methodology was tested by using individual and joint inversions of Magneotelluric, Controlled-source Electromagnetic (EM) and Global EM induction data.

  11. Psychosocial work characteristics, need for recovery and musculoskeletal problems predict psychological distress in a sample of British workers.

    PubMed

    Devereux, J J; Rydstedt, L W; Cropley, M

    2011-09-01

    From an original sample of 2454 participants free of self-reported psychological distress, 1463 workers completed a 15-month follow-up. Baseline measures included exposure to job demands, decision latitude, social support and need for recovery. Psychological distress was assessed using the General Health Questionnaire at baseline and at follow-up. The findings showed that medium and high exposure to job demands and social support increased the risk of reporting psychological distress at 15-months (relative risk (RR) = 1.65, 1.45). The highest adjusted RR was observed for workers reporting a high need for recovery after work (RR 2.12, 1.90) and this finding was independent of the effects of job demands, decision latitude and social support. Neither decision latitude, nor low back problems increased the risk of reporting future psychological distress, although neck problems (RR = 1.66) and hand/wrist problems (RR = 1.45) did. It was concluded that need for recovery appears to be an important indicator of individual workers who are at risk of developing psychological distress long term. STATEMENT OF RELEVANCE: This paper reports the findings of a longitudinal study showing that need for recovery from work was the strongest predictor, relative to psychosocial work characteristics (job demands, decision latitude and social support), and musculoskeletal problems, of psychological distress 15 months later in individuals initially free from distress. PMID:21851291

  12. Sex differences in childhood sexual abuse characteristics and victims’ emotional and behavioral problems: Findings from a national sample of youth

    PubMed Central

    Jaffee, Sara R.

    2010-01-01

    Objective The first objective of this study was to test for sex differences in four childhood sexual abuse characteristics---penetration, substantiation, perpetrator familial status, and multi-maltreatment---in a national sample of youth. The second objective was to test for sex differences in how these abuse characteristics were associated with victims’ emotional and behavioral problems. Methods The sample was drawn from the National Survey of Child and Adolescent Well-Being, a sample of children investigated by United States child welfare services. Youth in the current study (n = 573, including 234 adolescents) were investigated for alleged sexual abuse. Logistic regression and multivariate analysis of covariance were used to test for sex differences in abuse characteristics, and to determine whether sex moderated associations between abuse characteristics and emotional and behavioral problems. Results Girls were more likely than boys to have their abuse substantiated and to experience penetrative abuse (although differences in penetration status did not emerge among adolescents). Substantiation status and child age were positively associated with caregiver-reported internalizing and externalizing symptoms. Sex did not moderate the relationship between abuse characteristics and youth emotional and behavioral problems. Conclusions Sexual abuse characteristics might not be highly predictive factors when making decisions about services needs. Furthermore, there may not be a strong empirical basis for operating on the assumption that one sex is more vulnerable to negative consequences of abuse than the other, or that abuse affects girls and boys differently. The processes explaining why some victims exhibit more impairment than others are likely complex. PMID:20400178

  13. Academic Achievement in a National Sample: The Contribution of Self-Regulation and Motivational Beliefs beyond and above Parental Involvement

    ERIC Educational Resources Information Center

    Bembenutty, Hefer

    2005-01-01

    This study examined the predictive association between gender, ethnicity, and homework parental involvement, self-regulated learning processes, and motivational beliefs among 10th grade high school students. It was predicted that students' motivational beliefs and self-regulatory processes would be significant predictors of students' math academic…

  14. SASS Documentation: 1993-94 SASS Student Sampling Problems; Solutions for Determining the Numerators for the SASS Private School (3B) Second-Stage Factors. Working Paper Series.

    ERIC Educational Resources Information Center

    Cole, Cornette; Schwanz, Dennis J.

    This document contains two papers related to the 1993-94 Schools and Staffing Survey (SASS). The first paper documents some of the problems that were encountered during student sample selection and the methods used to resolve those problems. It also provides some suggestions to alleviate some of the problems in future SASS studies. Significant…

  15. Longitudinal Associations of Alcohol Involvement with Subjective Well-Being in Adolescence and Prediction to Alcohol Problems in Early Adulthood

    ERIC Educational Resources Information Center

    Mason, W. Alex; Spoth, Richard L.

    2011-01-01

    Adolescent alcohol involvement is associated with numerous negative outcomes, but also appears to have positive correlates, including subjective well-being. Additional research is needed to understand these paradoxical findings. The current study examines alcohol use, adverse alcohol-related (and other substance-related) consequences, and…

  16. An Examination of Dependence Power, Father Involvement, and Judgments about Violence in an At-Risk Community Sample of Mothers

    ERIC Educational Resources Information Center

    Samp, Jennifer A.; Abbott, Leslie

    2011-01-01

    Individuals sometimes remain in dysfunctional, and even violent, relationships due to a perceived dependence on a partner. We examined the influence of dependence power judgments (defined by a combined assessment of mother commitment, perceived father commitment, and perceived father alternatives) in a community sample of mothers potentially bound…

  17. The Impact of Gender and Family Processes on Mental Health and Substance Use Issues in a Sample of Court-Involved Female and Male Adolescents

    ERIC Educational Resources Information Center

    Gavazzi, Stephen M.; Lim, Ji-Young; Yarcheck, Courtney M.; Bostic, Jennifer M.; Scheer, Scott D.

    2008-01-01

    Greater empirical attention directed toward gender-sensitive assessment strategies that concentrate on family-specific factors is thought to be both timely and necessary, especially with regard to outcome variables associated with mental health and substance abuse in at-risk adolescent populations. A sample of 2,646 court-involved adolescents was…

  18. Self-Report Measures of Child and Adolescent Psychopathy as Predictors of Offending in Four Samples of Justice-Involved Youth

    ERIC Educational Resources Information Center

    Boccaccini, Marcus T.; Epstein, Monica; Poythress, Norman; Douglas, Kevin S.; Campbell, Justin; Gardner, Gail; Falkenbach, Diana

    2007-01-01

    The authors examined the relation between self-report psychopathy measures and official records of offending in four samples of justice-involved youth (total N = 447). Psychopathy measures included the Antisocial Process Screening Device (APSD) and a modified version of the Childhood Psychopathy Scale (mCPS). Measures of offending included the…

  19. The Trajectories of Child's Internalizing and Externalizing Problems, Social Competence and Adolescent Self-Reported Problems in a Finnish Normal Population Sample

    ERIC Educational Resources Information Center

    Korhonen, Marie; Luoma, Ilona; Salmelin, Raili K.; Helminen, Mika; Kaltiala-Heino, Riittakerttu; Tamminen, Tuula

    2014-01-01

    Group-based modeling techniques are increasingly used in developmental studies to explore the patterns and co-occurrence of internalizing and externalizing problems. Social competence has been found to reciprocally influence internalizing and externalizing problems, but studies on its associations with different patterns of these problems are…

  20. Reciprocal prospective associations between disordered eating and other psychological problems in a community sample of Swedish adolescent girls.

    PubMed

    Viborg, Njördur; Wångby-Lundh, Margit; Lundh, Lars-Gunnar

    2014-01-01

    Disordered eating and its associations with psychological difficulties and body satisfaction were prospectively studied in a community sample of 13-15 year old adolescent girls (N=428). General psychological difficulties (including hyperactivity-inattention) and lower levels of body satisfaction at T1 were found to predict disordered eating at follow-up one year later (T2). Furthermore, reciprocal associations were found between disordered eating and psychological difficulties (but not body dissatisfaction) so that disordered eating at T1 predicted general psychological difficulties (including hyperactivity-inattention) at T2. The results support the notion of a vicious interplay between disordered eating and other subclinical psychological problems, which may represent a potential mechanism for the development of clinically significant eating disorders. It is suggested that it could be important to identify these kinds of bidirectional processes at an early stage, in order to prevent further developments of clinical forms of psychopathology. PMID:24411769

  1. Salmonella gut invasion involves TTSS-2-dependent epithelial traversal, basolateral exit, and uptake by epithelium-sampling lamina propria phagocytes.

    PubMed

    Müller, Andreas J; Kaiser, Patrick; Dittmar, Kurt E J; Weber, Thomas C; Haueter, Sabine; Endt, Kathrin; Songhet, Pascal; Zellweger, Christa; Kremer, Marcus; Fehling, Hans-Jörg; Hardt, Wolf-Dietrich

    2012-01-19

    Salmonella Typhimurium causes diarrhea by infecting the epithelium and lamina propria of the intestinal mucosa and by secreting various effector proteins through type III secretion systems (TTSSs). However, the mechanisms by which Salmonella transverses the epithelium and is subsequently released into the lamina propria are poorly understood. Using a murine Salmonella-diarrhea model and in vivo microscopy, we show that epithelial traversal requires TTSS-1-mediated invasion and TTSS-2-dependent trafficking to the basolateral side. After being released into the lamina propria, the bacterium is transiently extracellular before being taken up by phagocytes, including CD11c(+)CX(3)CR1(high) monocytic phagocytes (MPs), which were found to constitutively sample cellular material shed from the basolateral side of the epithelium. Thus, Salmonella infects the cecal mucsa through a step-wise process wherein the bacterium transverses the epithelium through TTSS-2-dependent trafficking and then likely exploits lamina propria MPs, which are sampling the epithelium, to enter and replicate within the host. PMID:22264510

  2. ‘What Brings Him Here Today?’: Medical Problem Presentation Involving Children with Autism Spectrum Disorders and Typically Developing Children.

    PubMed

    Solomon, Olga; Heritage, John; Yin, Larry; Maynard, Douglas W; Bauman, Margaret L

    2016-02-01

    Conversation and discourse analyses were used to examine medical problem presentation in pediatric care.Healthcare visits involving children with ASD and typically developing children were analyzed. We examined how children’s communicative and epistemic capabilities, and their opportunities to be socialized into a competent patient role are interactionally achieved. We found that medical problem presentation is designed to contain a ‘pre-visit’ account of the interactional and epistemic work that children and caregivers carry out at home to identify the child’s health problems; and that the intersubjective accessibility of children’s experiences that becomes disrupted by ASD presents a dilemma to all participants in the visit. The article examines interactional roots of unmet healthcare needs and foregone medical care of people with ASD. PMID:26463739

  3. Mycotoxin Cocktail in the Samples of Oilseed Cake from Early Maturing Cotton Varieties Associated with Cattle Feeding Problems

    PubMed Central

    Yunus, Agha W.; Sulyok, Michael; Böhm, Josef

    2015-01-01

    Cottonseed cake in South East Asia has been associated with health issues in ruminants in the recent years. The present study was carried out to investigate the health issues associated with cottonseed cake feeding in dairy animals in Pakistan. All the cake samples were confirmed to be from early maturing cotton varieties (maturing prior to or during Monsoon). A survey of the resource persons indicated that the feeding problems with cottonseed cake appeared after 4–5 months of post-production storage. All the cake samples had heavy bacterial counts, and contaminated with over a dozen different fungal genera. Screening for toxins revealed co-contamination with toxic levels of nearly a dozen mycotoxins including aflatoxin B1 + B2 (556 to 5574 ppb), ochratoxin A + B (47 to 2335 ppb), cyclopiazonic acid (1090 to 6706 ppb), equisetin (2226 to 12672 ppb), rubrofusarin (81 to 1125), tenuazonic acid (549 to 9882 ppb), 3-nitropropionic acid (111 to 1032 ppb), and citrinin (29 to 359 ppb). Two buffalo calves in a diagnostic feed trial also showed signs of complex toxicity. These results indicate that inappropriate processing and storage of the cake, in the typical conditions of the subcontinent, could be the main contributory factors regarding the low quality of cottonseed cake. PMID:26075378

  4. Mycotoxin Cocktail in the Samples of Oilseed Cake from Early Maturing Cotton Varieties Associated with Cattle Feeding Problems.

    PubMed

    Yunus, Agha W; Sulyok, Michael; Böhm, Josef

    2015-06-01

    Cottonseed cake in South East Asia has been associated with health issues in ruminants in the recent years. The present study was carried out to investigate the health issues associated with cottonseed cake feeding in dairy animals in Pakistan. All the cake samples were confirmed to be from early maturing cotton varieties (maturing prior to or during Monsoon). A survey of the resource persons indicated that the feeding problems with cottonseed cake appeared after 4-5 months of post-production storage. All the cake samples had heavy bacterial counts, and contaminated with over a dozen different fungal genera. Screening for toxins revealed co-contamination with toxic levels of nearly a dozen mycotoxins including aflatoxin B1 + B2 (556 to 5574 ppb), ochratoxin A + B (47 to 2335 ppb), cyclopiazonic acid (1090 to 6706 ppb), equisetin (2226 to 12672 ppb), rubrofusarin (81 to 1125), tenuazonic acid (549 to 9882 ppb), 3-nitropropionic acid (111 to 1032 ppb), and citrinin (29 to 359 ppb). Two buffalo calves in a diagnostic feed trial also showed signs of complex toxicity. These results indicate that inappropriate processing and storage of the cake, in the typical conditions of the subcontinent, could be the main contributory factors regarding the low quality of cottonseed cake. PMID:26075378

  5. Gas generation and migration studies involving recently generated /sup 238/Pu-contaminated waste for the TRU Waste Sampling Program

    SciTech Connect

    Zerwekh, A.; Warren, J.L.

    1986-07-01

    This study is part of the multicontractor TRU Waste Sampling Program. Radiolytically generated gases were vented through a filtering device to determine its effectiveness in maintaining hydrogen concentrations within acceptably safe levels. In the second part of the study measurements were made to determine the ability of these gases, particularly hydrogen, to migrate through a sealed rigid polyethylene drum liner. Void volumes in these drums were found to be generally in excess of 90%. The carbon composite filter was found to satisfactorily vent hydrogen up to moderately high levels of alpha activity in the waste substrate. The sealed 90-mil liner was found to inhibit, but not prevent, the migration of hydrogen and other radiolytically generated gases.

  6. Improvements of the Bethe stopping power theory and their application to problems involving radiation in the environment

    NASA Astrophysics Data System (ADS)

    Sinky, Hussein Mohammed

    The latest advances in radiation oncology emphasizes the importance of the theory of energy loss of charged particles through matter. Since the development of the Bethe-Bloch stopping power for heavy charged incident particles in 1930, many corrections have been proposed to improve this equation's theoretical approximation. The region of applicability of this formula, with respect to the velocity and the charge of the incident particle as well as the characteristics of the target, is restricted by the validity of the approximation adopted. One of the major unsolved problems is the relativistic treatment of the inner-shell electrons for medium and heavy target elements. The stopping power theory treats atomic electrons non-relativistically for these targets which put serious limitation on the theory because the basic sum rules on which the theory relies are not amenable to vigorous relativistic generalization as pointed out by Fano. To solve this problem we assume completeness by employing the Dirac Hamiltonian, and then present a semi-relativistic approach to order v 2/c2 following the Foldy-Wouthuysen-Transformation (FWT) to exclude the contributions from the negative-energy states. To establish this goal we developed a very elegant, practical, and accurate step-by-step procedure using Baker-Hausdroff Lemma to do the FWT to any desired order for any functions of coordinate or momentum operator, or to any entire functions of both coordinate and momentum operators. We applied this procedure to general function of position where the result is then applied to find the TRK and Bethe sum rules by using semirelativistic Hamiltonian. This procedure can be used to find any desired sum rule by doing more computation relations of the transformed Hamiltonian of the system with the transformed function of position. For example, Sk sum rule will require k times commutation relations to be calculated. The resulting Bethe sum rule relativistic correction is then used to find the

  7. Computationally efficient parabolic equation solutions to seismo-acoustic problems involving thin or low-shear elastic layers.

    PubMed

    Metzler, Adam M; Collis, Jon M

    2013-04-01

    Shallow-water environments typically include sediments containing thin or low-shear layers. Numerical treatments of these types of layers require finer depth grid spacing than is needed elsewhere in the domain. Thin layers require finer grids to fully sample effects due to elasticity within the layer. As shear wave speeds approach zero, the governing system becomes singular and fine-grid spacing becomes necessary to obtain converged solutions. In this paper, a seismo-acoustic parabolic equation solution is derived utilizing modified difference formulas using Galerkin's method to allow for variable-grid spacing in depth. Propagation results are shown for environments containing thin layers and low-shear layers. PMID:23556690

  8. A population of Langerin-positive dendritic cells in murine Peyer's patches involved in sampling β-glucan microparticles.

    PubMed

    De Jesus, Magdia; Ostroff, Gary R; Levitz, Stuart M; Bartling, Toni R; Mantis, Nicholas J

    2014-01-01

    Glucan particles (GPs) are 2-4 μm hollow, porous shells composed of 1,3-β-D-glucan that have been effectively used for oral targeted-delivery of a wide range of payloads, including small molecules, siRNA, DNA, and protein antigens. While it has been demonstrated that the transepithelial transport of GPs is mediated by Peyer's patch M cells, the fate of the GPs once within gut-associated lymphoid tissue (GALT) is not known. Here we report that fluorescently labeled GPs administered to mice by gavage accumulate in CD11c+ DCs situated in Peyer's patch sub-epithelial dome (SED) regions. GPs appeared in DCs within minutes after gavage and remained within the SED for days afterwards. The co-administration or sequential administration of GPs with differentially labeled GPs or poly(lactic-co-glycolic acid) nanoparticles demonstrated that the SED DC subpopulation in question was capable of internalizing particles of different sizes and material compositions. Phenotypic analysis identified the GP-containing DCs as being CD8α- and CD11blo/-, suggesting they are the so-called myeloid and/or double negative (DN) subset(s) of PP DCs. A survey of C-type lectin receptors (CLRs) known to be expressed by leukocytes within the intestinal mucosa revealed that GP-containing SED DCs were positive for Langerin (CD207), a CLR with specificity for β-D-glucan and that has been shown to mediate the internalization of a wide range of microbial pathogens, including bacteria, viruses and fungi. The presence of Langerin+ DCs in the SED as determined by immunofluorescence was confirmed using Langerin E-GFP transgenic mice. In summary, our results demonstrate that following M cell-mediated transepithelial transport, GPs (and other micro/nanoparticles) are sampled by a population of SED DCs distinguished from other Peyer's patch DC subsets by their expression of Langerin. Future studies will be aimed at defining the role of Langerin in antigen sampling and antigen presentation within the

  9. Confidentiality, informed consent, and children's participation in research involving stored tissue samples: interviews with medical professionals from the Middle East.

    PubMed

    Alahmad, Ghiath; Al Jumah, Mohammed; Dierickx, Kris

    2015-01-01

    Ethical issues regarding research biobanks continue to be a topic of intense debate, especially issues of confidentiality, informed consent, and child participation. Although considerable empirical literature concerning research biobank ethics exists, very little information is available regarding the opinions of medical professionals doing genetics research from the Middle East, especially Arabic speaking countries. Ethical guidelines for research biobanks are critically needed as some countries in the Middle East are starting to establish national research biobanks. Islam is the dominant religion in these countries, and it affects people's behavior and influences their positions. Moreover, communities in these countries enjoy a set of customs, traditions and social norms, and have social and familial structures that must be taken into account when developing research policies. We interviewed 12 medical professionals from the Middle East currently working with stored tissue samples to document their opinions. We found general agreement. Participants' primary concerns were similar to the views of researchers internationally. Since children tend to represent a high percentage of Middle Eastern populations, and because children's bodies are not just small adult bodies, the interviewed professionals strongly believed that it is imperative to include children in biobank research. Participants generally believed that protecting confidentiality is socially very important and that informed consent/assent must be obtained from both adult and child participants. This study provides a starting point for additional studies. PMID:25981282

  10. Problems involving the determination of the column-only band broadening in columns producing narrow and tailed peaks.

    PubMed

    Vanderheyden, Yoachim; Vanderlinden, Kim; Broeckhoven, Ken; Desmet, Gert

    2016-04-01

    We have investigated which of the different existing peak variance read-out methods (including the effect of a deconvolution pre-treatment method) are most suited to eliminate the system contribution from the total observed band broadening observed in LC systems. Emphasis is put on the most demanding case, i.e., the measurement of non-retained component peaks, which typically are very narrow and tailed. The problem with such peaks is that the method that is generally considered to be the only mathematically correct method (i.e., the method of moments) leads to peak variance values that are so strongly dominated by the tail of the peak that they become highly exaggerated and practically meaningless (i.e., they are dominated by the peak width at 10 or 12σt, which corresponds to resolutions and peak purities that are so high they are never pursued in practice). Interestingly, filtering away the extra-column contribution from the entire peak shape using peak deconvolution (wherein not only the second order moment is corrected but also all other moments) produces corrected 4σt- and half height peak widths that are physically meaningful, i.e., the corrected values allow to make sufficiently accurate predictions of how the peak width at 4σt and at half height changes when the column length changes. This result now allows to navigate away from the classical method of moments to define the column plate height, and resort to plate heights based on the practically much more relevant 4σt- and 5σt-widths, provided theses are corrected via peak deconvolution. PMID:26947164

  11. Drug-related problems in a sample of outpatients with chronic diseases: a cross-sectional study from Jordan

    PubMed Central

    Al-Azzam, Sayer I; Alzoubi, Karem H; AbuRuz, Salah; Alefan, Qais

    2016-01-01

    Optimization of drug therapy and preventing drug-related problems (DRPs) are major factors to improve health care, reduce expenditure, and potentially save lives. This study aimed at describing the types, numbers, and frequencies of DRPs in the outpatient settings of a group of hospitals in Jordan. The study was set in the cardiology, endocrine, and respiratory outpatient clinics of five major hospitals in Jordan. Patients who visited the above clinics during the period from September 2012 to December 2013, were candidates for this study. Each included subject was fully assessed for DRPs by clinical pharmacists according to a specially designed and validated pharmaceutical care manual. The main outcome measures were the number and types of DRPs. Data were collected from 2,898 patients (mean age ± standard deviation: 56.59±13.5 years). The total number of identified DRPs was 32,348, with an average of 11.2 DRPs per patient. The most common DRPs were a need for additional or more frequent monitoring, a problem in patients’ adherence to self-care activities or nonpharmacological therapy, and that the patient was not given instruction in or did not understand nonpharmacological therapy or self-care advice. The numbers of DRPs per patient in our sample were associated with older age (>57 years), being unmarried, having an education level of high school or less, not having health insurance, and the presence of certain clinical conditions, including hypertension, diabetes mellitus, dyslipidemia, ischemic heart disease, cardiac catheterization, heart failure, and gout. In conclusion, implementation of clinical pharmacy services is a strategy to limit DRPs. Certain patient populations are more vulnerable to DRPs. PMID:26937195

  12. Systematic evaluation of sequential geostatistical resampling within MCMC for posterior sampling of near-surface geophysical inverse problems

    NASA Astrophysics Data System (ADS)

    Ruggeri, Paolo; Irving, James; Holliger, Klaus

    2015-08-01

    We critically examine the performance of sequential geostatistical resampling (SGR) as a model proposal mechanism for Bayesian Markov-chain-Monte-Carlo (MCMC) solutions to near-surface geophysical inverse problems. Focusing on a series of simple yet realistic synthetic crosshole georadar tomographic examples characterized by different numbers of data, levels of data error and degrees of model parameter spatial correlation, we investigate the efficiency of three different resampling strategies with regard to their ability to generate statistically independent realizations from the Bayesian posterior distribution. Quite importantly, our results show that, no matter what resampling strategy is employed, many of the examined test cases require an unreasonably high number of forward model runs to produce independent posterior samples, meaning that the SGR approach as currently implemented will not be computationally feasible for a wide range of problems. Although use of a novel gradual-deformation-based proposal method can help to alleviate these issues, it does not offer a full solution. Further, we find that the nature of the SGR is found to strongly influence MCMC performance; however no clear rule exists as to what set of inversion parameters and/or overall proposal acceptance rate will allow for the most efficient implementation. We conclude that although the SGR methodology is highly attractive as it allows for the consideration of complex geostatistical priors as well as conditioning to hard and soft data, further developments are necessary in the context of novel or hybrid MCMC approaches for it to be considered generally suitable for near-surface geophysical inversions.

  13. Preschool Boys' Development of Emotional Self-regulation Strategies in a Sample At-risk for Behavior Problems

    PubMed Central

    Supplee, Lauren H.; Skuban, Emily Moye; Trentacosta, Christopher J.; Shaw, Daniel S.; Stoltz, Emilee

    2011-01-01

    Little longitudinal research has been conducted on changes in children's emotional self-regulation strategy (SRS) use after infancy, particularly for children at risk. The current study examined changes in boys' emotional SRS from toddlerhood through preschool. Repeated observational assessments using delay of gratification tasks at ages 2, 3, and 4 were examined with both variable- and person-oriented analyses in a low-income sample of boys (N = 117) at-risk for early problem behavior. Results were consistent with theory on emotional SRS development in young children. Children initially used more emotion-focused SRS (e.g., comfort seeking) and transitioned to greater use of planful SRS (e.g., distraction) by age 4. Person-oriented analysis using trajectory analysis found similar patterns from 2–4, with small groups of boys showing delayed movement away from emotion-focused strategies or delay in the onset of regular use of distraction. The results provide a foundation for future research to examine the development of SRS in low-income young children. PMID:21675542

  14. Effects of Maternal Smoking during Pregnancy on Offspring Externalizing Problems: Contextual Effects in a Sample of Female Twins.

    PubMed

    Palmer, Rohan H C; Bidwell, L Cinnamon; Heath, Andrew C; Brick, Leslie A; Madden, Pamela A F; Knopik, Valerie S

    2016-05-01

    Studies of maternal smoking during pregnancy (MSDP) suggest increased risk for cognitive impairment and psychiatric outcomes. However, it is uncertain whether these associations are the direct result of MSDP or related to confounding familial variables associated with MSDP. The current study employed propensity score analysis to examine the effects of MSDP on offspring EXT using data from a large sample of 979 unrelated mothers. Logistic regression models were used to determine the propensity that the offspring of these mothers were likely to be exposed to MSDP [i.e., smoked during only the first trimester (MSDP-EARLY[E]) or smoked throughout their pregnancy (MSDP-THROUGHOUT[T])] given known familial confounders. Analyses focused on the effect of MSDP-E/T on the EXT behavior in offspring of these mothers (N = 1616) were conducted across the distribution of liability for MSDP-E/T and at different levels of risk for MSDP-E/T. MSDP-E/T was associated with offspring EXT problems, but the effects were partly confounded by the familial liability for MSDP. Further, the observed effects were not consistent across all levels of the MSDP risk distribution. These findings suggest a direct association between MSDP and offspring EXT behaviors, and that varied associations observed across studies may be the result of differences in the level of familial confounders that also have an effect on offspring EXT. PMID:26826031

  15. Competitiveness facets and sensation seeking as predictors of problem gambling among a sample of university student gamblers.

    PubMed

    Harris, Nicholas; Newby, Jennifer; Klein, Rupert G

    2015-06-01

    Understanding the factors that contribute to problem gambling (PG) is imperative. Individual differences in sensation seeking (SS), as measured by the Sensation Seeking Scale Form (SSS-V), have been found to be predictive of PG among university student samples. However, what is less clear, is if the four SSS-V subscales capture unique facets of SS that are particularly predictive of PG. Much less studied than SS, competitiveness has also been found to be predictive of PG. The Competitiveness Orientation Measure (COM) is a newly developed measure of competitiveness, comprising of four facets. The main purpose of the current study was to examine if these four facets of competitiveness predicted variance in PG over and above the variance predicted by the four SSS-V subscales. Participants included 158 university student gamblers. Sequential regression analysis showed that after accounting for gender, age, and the four SSS-V subscales the only facet of the COM found to be a significant predictor of PG severity was Dominant Competitiveness. Dominant Competitiveness predicted an additional 11% of PG severity. These results provide support for the Dominant Competitiveness subscale of the COM as having utility in predicting PG over and above the predictive utility of the SSS-V subscales. Practical implications for the current findings are discussed. PMID:24337941

  16. Caretaker mental health and family environment factors are associated with adolescent psychiatric problems in a Vietnamese sample

    PubMed Central

    Stratton, Kelcey Jane; Edwards, Alexis Christine; Overstreet, Cassie; Richardson, Lisa; Tran, Trinh Luong; Trung, Lam Tu; Tam, Nguyen Thanh; Tuan, Tran; Buoi, La Thi; Ha, Tran Thu; Thach, Tran Duc; Amstadter, Ananda Beth

    2015-01-01

    Little is known about risk factors for adolescent mental health in Vietnam. The present study investigated the relationship between caretaker mental health and adolescent mental health in a cross-sectional Vietnamese sample. Primary caretakers completed measures of their own mental distress and general health status using the Self-Reporting Questionnaire-20 (SRQ-20) as well as reports of adolescent mental health using the parent version of the Strengths and Difficulties Questionnaire (SDQ). Multivariate regression models were used to examine the relationships between the caretaker and adolescent health variables. The demographic factors of age, sex, ethnicity, religious affiliation, and household wealth status demonstrated significant relationships with SDQ subscale scores. Caretaker mental health was positively associated with adolescent mental health, and this association remained significant even after accounting for other relevant demographic variables and caretaker general health status. Understanding correlates of adolescent mental health difficulties may help identify youth and families at risk for developing psychiatric problems and inform mental health interventions in Vietnam. PMID:25204862

  17. Caretaker mental health and family environment factors are associated with adolescent psychiatric problems in a Vietnamese sample.

    PubMed

    Stratton, Kelcey Jane; Edwards, Alexis Christine; Overstreet, Cassie; Richardson, Lisa; Tran, Trinh Luong; Trung, Lam Tu; Tam, Nguyen Thanh; Tuan, Tran; Buoi, La Thi; Ha, Tran Thu; Thach, Tran Duc; Amstadter, Ananda Beth

    2014-12-15

    Little is known about risk factors for adolescent mental health in Vietnam. The present study investigated the relationship between caretaker mental health and adolescent mental health in a cross-sectional Vietnamese sample. Primary caretakers completed measures of their own mental distress and general health status using the Self-Reporting Questionnaire-20 (SRQ-20) as well as reports of adolescent mental health using the parent version of the Strengths and Difficulties Questionnaire (SDQ). Multivariate regression models were used to examine the relationships between the caretaker and adolescent health variables. The demographic factors of age, sex, ethnicity, religious affiliation, and household wealth status demonstrated significant relationships with SDQ subscale scores. Caretaker mental health was positively associated with adolescent mental health, and this association remained significant even after accounting for other relevant demographic variables and caretaker general health status. Understanding correlates of adolescent mental health difficulties may help identify youth and families at risk for developing psychiatric problems and inform mental health interventions in Vietnam. PMID:25204862

  18. Preschool boys' development of emotional self-regulation strategies in a sample at risk for behavior problems.

    PubMed

    Supplee, Lauren H; Skuban, Emily Moye; Trentacosta, Christopher J; Shaw, Daniel S; Stoltz, Emilee

    2011-01-01

    Little longitudinal research has been conducted on changes in children's emotional self-regulation strategy (SRS) use after infancy, particularly for children at risk. In this study, the authors examined changes in boys' emotional SRS from toddlerhood through preschool. Repeated observational assessments using delay of gratification tasks at ages 2, 3, and 4 years were examined with both variable- and person-oriented analyses in a low-income sample of boys (N = 117) at risk for early problem behavior. Results were consistent with theory on emotional SRS development in young children. Children initially used more emotion-focused SRS (e.g., comfort seeking) and transitioned to greater use of planful SRS (e.g., distraction) by 4 years of age. Person-oriented analysis using trajectory analysis found similar patterns from 2 to 4 years, with small groups of boys showing delayed movement away from emotion-focused strategies or delay in the onset of regular use of distraction. The results provide a foundation for future researchers to examine the development of SRS in low-income young children. PMID:21675542

  19. Self-report measures of executive function problems correlate with personality, not performance-based executive function measures, in nonclinical samples.

    PubMed

    Buchanan, Tom

    2016-04-01

    Researchers and clinicians often measure executive function in patients and normal samples. In addition to cognitive tests that objectively measure executive function, several instruments have been developed that address individuals' everyday experience of executive problems. Such self-report measures of executive problems may have value, but there are questions about the extent to which they tap objectively measurable executive problems or are influenced by variables such as personality. Relationships between self-reported executive problems, personality, and cognitive test performance were assessed in 3 separate, well-powered, methodologically distinct correlational studies using nonclinical samples. These studies used multiple measures of personality and self-reported executive function problems. Across all 3 studies, self-reported executive function problems were found to correlate with neuroticism and with low conscientiousness, with medium to large effect sizes. However self-reported problems did not correlate with performance on Trail Making, Phonemic Fluency, Semantic Fluency, or Digit Span tests tapping executive function. A key implication of these findings is that in nonclinical samples, self-report questionnaires may not be proxies for executive functioning as measured by neuropsychological tests. (PsycINFO Database Record PMID:26191609

  20. Mental Health Problems and Overweight in a Nationally Representative Sample of Adolescents: Effects of Race and Ethnicity

    PubMed Central

    BeLue, Rhonda; Francis, Lori Ann; Colaco, Brendon

    2009-01-01

    OBJECTIVES In this study we examined the relation between mental health problems and weight in a population-based study of youth aged 12 to 17 years and whether the association between mental health problems and weight is moderated by race and ethnicity. METHODS We used 2003 National Survey on Children’s Health data. Logistic regression was used to arrive at adjusted odds ratios showing the relation between BMI and mental health problems. RESULTS Compared with their nonoverweight counterparts, both white and Hispanic youth who were overweight were significantly more likely to report depression or anxiety, feelings of worthlessness or inferiority, behavior problems, and bullying of others. Odds ratios relating mental health problems and BMI in black subjects were not statistically significant except for physician diagnosis of depression. CONCLUSIONS Our results suggest that, when addressing youth overweight status, mental health problems also need to be addressed. Given that the relationship between mental health problems and youth overweight differs according to race/ethnic group, public health programs that target overweight youth should be cognizant of potential comorbid mental health problems and that race/ethnicity may play a role in the relationship between mental health and overweight status. PMID:19171640

  1. Predictors of Parent Stress in a Sample of Children with ASD: Pain, Problem Behavior, and Parental Coping

    ERIC Educational Resources Information Center

    Walsh, Caitlin E.; Mulder, Emile; Tudor, Megan E.

    2013-01-01

    Studies have shown that children with ASD have increased severity and incidence of pain symptoms compared to typically developing children and children with other disorders. Pain has also been shown to act as a setting event for problem behavior. Further, problem behavior is one of the biggest impediments to quality of life for families and highly…

  2. Stress, Mental Health, and Substance Abuse Problems in a Sample of Diversion Program Youths: An Exploratory Latent Class Analysis

    ERIC Educational Resources Information Center

    Dembo, Richard; Briones, Rhissa; Gulledge, Laura; Karas, Lora; Winters, Ken C.; Belenko, Steven; Greenbaum, Paul E.

    2012-01-01

    Reflective of interest in mental health and substance abuse issues among youths involved with the justice system, we performed a latent class analysis on baseline information collected on 100 youths involved in two diversion programs. Results identified two groups of youths: Group 1: a majority of the youths, who had high levels of delinquency,…

  3. Transactional effects among maternal depression, neighborhood deprivation, and child conduct problems from early childhood through adolescence: A tale of two low-income samples.

    PubMed

    Shaw, Daniel S; Sitnick, Stephanie L; Reuben, Julia; Dishion, Thomas J; Wilson, Melvin N

    2016-08-01

    The current study sought to advance our understanding of transactional processes among maternal depression, neighborhood deprivation, and child conduct problems (CP) using two samples of low-income families assessed repeatedly from early childhood to early adolescence. After accounting for initial levels of negative parenting, independent and reciprocal effects between maternal depressive symptoms and child CP were evident across both samples, beginning in early childhood and continuing through middle childhood and adolescence. In addition, neighborhood effects were consistently found in both samples after children reached age 5, with earlier neighborhood effects on child CP and maternal depression found in the one exclusively urban sample of families with male children. The results confirm prior research on the independent contribution of maternal depression and child CP to the maintenance of both problem behaviors. The findings also have implications for designing preventative and clinical interventions to address child CP for families living in high-risk neighborhoods. PMID:27427808

  4. Initial Reliability and Validity of the Life Satisfaction Scale for Problem Youth in a Sample of Drug Abusing and Conduct Disordered Youth

    ERIC Educational Resources Information Center

    Donohue, Brad; Teichner, Gordon; Azrin, Nathan; Weintraub, Noah; Crum, Thomas A.; Murphy, Leah; Silver, N. Clayton

    2003-01-01

    Responses to Life Satisfaction Scale for Problem Youth (LSSPY) items were examined in a sample of 193 substance abusing and conduct disordered adolescents. In responding to the LSSPY, youth endorse their percentage of happiness (0 to 100%) in twelve domains (i.e., friendships, family, school, employment/work, fun activities, appearance, sex…

  5. Optimization of high-reliability-based hydrological design problems by robust automatic sampling of critical model realizations

    NASA Astrophysics Data System (ADS)

    Bayer, Peter; de Paly, Michael; Bürger, Claudius M.

    2010-05-01

    This study demonstrates the high efficiency of the so-called stack-ordering technique for optimizing a groundwater management problem under uncertain conditions. The uncertainty is expressed by multiple equally probable model representations, such as realizations of hydraulic conductivity. During optimization of a well-layout problem for contaminant control, a ranking mechanism is applied that extracts those realizations that appear most critical for the optimization problem. It is shown that this procedure works well for evolutionary optimization algorithms, which are to some extent robust against noisy objective functions. More precisely, differential evolution (DE) and the Covariance Matrix Adaptation Evolution Strategy (CMA-ES) are applied. Stack ordering is comprehensively investigated for a plume management problem at a hypothetical template site based on parameter values measured at and on a geostatistical model developed for the Lauswiesen study site near Tübingen, Germany. The straightforward procedure yields computational savings above 90% in comparison to always evaluating the full set of realizations. This is confirmed by cross testing with four additional validation cases. The results show that both evolutionary algorithms obtain highly reliable near-optimal solutions. DE appears to be the better choice for cases with significant noise caused by small stack sizes. On the other hand, there seems to be a problem-specific threshold for the evaluation stack size above which the CMA-ES achieves solutions with both better fitness and higher reliability.

  6. Predictors of general medical and psychological treatment use among a national sample of peacekeeping veterans with health problems.

    PubMed

    Elhai, Jon D; Don Richardson, J; Pedlar, David J

    2007-01-01

    We investigated general medical and psychological treatment use predictors among peacekeeping veterans with health problems, aiming to find those characteristics most associated with treatment use intensity (i.e., visit counts). One thousand one hundred and thirty-two male Canadian Forces peacekeeping veterans registered with Veterans Affairs for health problems were randomly recruited for a prospective national survey. Regression analyses for treatment use intensity controlled for age, total time deployed and health problems (covariates), and examined the incremental contribution of depression and post-traumatic stress disorder (PTSD) severity on health service use intensity. Results revealed that after controlling for covariates, the depression and PTSD model was associated with increased medical and psychological treatment use intensity. Medical use intensity was significantly predicted by married status, greater depression and health problems; psychological treatment use intensity was predicted by younger age, greater PTSD severity and health problems. This study highlights the importance of an integrated primary care-mental health service delivery model for veterans. PMID:16965892

  7. Consideration of some sampling problems in the on-line analysis of batch processes by low-field NMR spectrometry.

    PubMed

    Nordon, Alison; Diez-Lazaro, Alvaro; Wong, Chris W L; McGill, Colin A; Littlejohn, David; Weerasinghe, Manori; Mamman, Danladi A; Hitchman, Michael L; Wilkie, Jacqueline

    2008-03-01

    A low-field medium-resolution NMR spectrometer, with an operating frequency of 29 MHz for 1H, has been assessed for on-line process analysis. A flow cell that incorporates a pre-magnetisation region has been developed to minimise the decrease in the signal owing to incomplete polarisation effects. The homogeneous esterification reaction of crotonic acid and 2-butanol was monitored using a simple sampling loop; it was possible to monitor the progression of the reaction through changes in CH signal areas of butanol and butyl crotonate. On-line analysis of heterogeneous water-toluene mixtures proved more challenging and a fast sampling loop system was devised for use with a 5 L reactor. The fast sampling loop operated at a flow rate of 8 L min(-1) and a secondary sampling loop was used to pass a sub-sample through the NMR analyser at a slower (mL min(-1)) rate. It was shown that even with super-isokinetic sampling conditions, unrepresentative sampling could occur owing to inadequate mixing in the reactor. However, it was still possible to relate the 1H NMR signal obtained at a flow rate of 60 mL min(-1) to the composition of the reactor contents. PMID:18299748

  8. Predictors and Moderators of Parent Training Efficacy in a Sample of Children with Autism Spectrum Disorders and Serious Behavioral Problems

    ERIC Educational Resources Information Center

    Farmer, Cristan; Lecavalier, Luc; Yu, Sunkyung; Arnold, L. Eugene; McDougle, Christopher J.; Scahill, Lawrence; Handen, Benjamin; Johnson, Cynthia R.; Stigler, Kimberly A.; Bearss, Karen; Swiezy, Naomi B.; Aman, Michael G.

    2012-01-01

    The Research Units on Pediatric Psychopharmacology-Autism Network reported additional benefit when adding parent training (PT) to antipsychotic medication in children with autism spectrum disorders and serious behavior problems. The intent-to-treat analyses were rerun with putative predictors and moderators. The "Home Situations Questionnaire"…

  9. Attention Problems Mediate the Association between Severity of Physical Abuse and Aggressive Behavior in a Sample of Maltreated Early Adolescents

    ERIC Educational Resources Information Center

    Garrido, Edward F.; Taussig, Heather N.; Culhane, Sara E.; Raviv, Tali

    2011-01-01

    Empirical evidence has accumulated documenting an association between childhood physical abuse and aggressive behavior. Relatively fewer studies have explored possible mediating mechanisms that may explain this association. The purpose of the current study was to examine whether caregiver- and youth-reported attention problems mediate the…

  10. The Problem Areas in Diabetes (PAID) scale: psychometric evaluation survey in a Greek sample with type 2 diabetes.

    PubMed

    Papathanasiou, A; Koutsovasilis, A; Shea, S; Philalithis, A; Papavasiliou, S; Melidonis, A; Lionis, C

    2014-05-01

    Several instruments have been developed for the assessment of emotional distress in patients with diabetes. The Problem Areas in Diabetes Scale (PAID) is a brief self-report scale that evaluates diabetes-related distress. There is a lack of validated instruments for the evaluation of psychological aspects in patients with diabetes in Greek language. The current study was conducted to translate and adapt the PAID scale in Greek language and to evaluate the psychometric properties in two different study populations of patients with diabetes. The aim of this study was to translate the Problem Areas in Diabetes (PAID) scale into Greek, adapt it culturally to Greece and determine its psychometric properties. The translation process included two forward translations, reconciliation, backward translation and pre-testing steps. The validation incorporated the exploration of internal consistency (Cronbach's alpha), test-retest reliability (interclass correlation coefficient), construct validity (exploratory factor analysis) and responsiveness (Spearman correlation coefficient). Participants included 101 consecutive patients from a rural primary healthcare centre and 101 patients from an urban hospital. All patients completed the PAID scale and the Short Form-36 (SF-36) version 2. Internal consistency considered good (Cronbach's alpha = 0.948). Interclass correlation coefficient was 0.942 (95% CI 0.915-0.961). Factor analysis yielded three factors: 'Diabetes-related emotional problems' (51.79% variance, Cronbach's alpha = 0.910), 'Food-related problems' (9.55% variance, Cronbach's alpha = 0.824) and 'Social support-related problems' (5.96% variance, Cronbach's alpha = 0.704). Screen plot test and conceptual congruency of items supported a three-factor solution. Total PAID showed a negative correlation with both SF-36 mental component summary (r = -0.733, P < 0.0001) and SF-36 physical component summary (r = -0.594, P < 0.0001). Our findings indicate that the Greek version of