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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. 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…

  19. 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…

  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

    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

  2. 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.

  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 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.

  7. 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.

  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. 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…

  8. 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)…

  9. 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…

  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. 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…

  3. 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)

  4. 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…

  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. 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.…

  8. 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…

  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. 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…

  20. 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…

  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. 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…

  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. 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

  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. 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.…

  4. 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…

  5. "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…

  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. 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…

  13. 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)

  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. 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…

  18. 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…

  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. 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

  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. 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

  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. 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…

  19. 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…

  20. 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.…

  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. 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.…

  5. 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…

  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. 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

  15. 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

  16. 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.

  17. 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.

  18. 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

  19. 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

  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. 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…

  18. 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…

  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. 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

  14. 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

  15. 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

  16. 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

  17. 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

  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

  11. From plans to actions in patient and public involvement: qualitative study of documented plans and the accounts of researchers and patients sampled from a cohort of clinical trials

    PubMed Central

    Buck, Deborah; Gamble, Carrol; Dudley, Louise; Preston, Jennifer; Hanley, Bec; Williamson, Paula R; Young, Bridget

    2014-01-01

    Patient and public involvement (PPI) in research is increasingly required, although evidence to inform its implementation is limited. Objective Inform the evidence base by describing how plans for PPI were implemented within clinical trials and identifying the challenges and lessons learnt by research teams. Methods We compared PPI plans extracted from clinical trial grant applications (funded by the National Institute for Health Research Health Technology Assessment Programme between 2006 and 2010) with researchers’ and PPI contributors’ interview accounts of PPI implementation. Analysis of PPI plans and transcribed qualitative interviews drew on the Framework technique. Results Of 28 trials, 25 documented plans for PPI in funding applications and half described implementing PPI before applying for funding. Plans varied from minimal to extensive, although almost all anticipated multiple modes of PPI. Interview accounts indicated that PPI plans had been fully implemented in 20/25 trials and even expanded in some. Nevertheless, some researchers described PPI within their trials as tokenistic. Researchers and contributors noted that late or minimal PPI engagement diminished its value. Both groups perceived uncertainty about roles in relation to PPI, and noted contributors’ lack of confidence and difficulties attending meetings. PPI contributors experienced problems in interacting with researchers and understanding technical language. Researchers reported difficulties finding ‘the right’ PPI contributors, and advised caution when involving investigators’ current patients. Conclusions Engaging PPI contributors early and ensuring ongoing clarity about their activities, roles and goals, is crucial to PPI's success. Funders, reviewers and regulators should recognise the value of preapplication PPI and allocate further resources to it. They should also consider whether PPI plans in grant applications match a trial's distinct needs. Monitoring and reporting PPI

  12. Personality dimensions and emotional problems: the mediating role of irrational beliefs in Pakistani adult non-clinical sample.

    PubMed

    Jibeen, Tahira

    2015-03-01

    This study presents the first examination of the relation between the Big Five personality traits, irrational beliefs and emotional problems in Pakistan, which is an understudied country in the psychological distress literature. A total of 195 participants (aged 25-60 years), employees at COMSATS University, completed a demographic information sheet, the Big Five Personality Questionnaire, the Irrational Belief Inventory and two subscales of the Brief Symptom Inventory including depression and anxiety. Direct effects of neuroticism, openness and conscientiousness were also observed for depression and anxiety. Structural Equation Modelling demonstrated that irrational beliefs played a significant mediating role in the relationship between neuroticism and anxiety and neuroticism and depression. The results highlight the importance of cognitive beliefs in functionally linking personality traits and emotional problems. PMID:25721878

  13. Neurobehavioral factors associated with referral for learning problems in a community sample: evidence for an adaptational model for learning disorders.

    PubMed

    Waber, Deborah P; Weiler, Michael D; Forbes, Peter W; Bernstein, Jane H; Bellinger, David C; Rappaport, Leonard

    2003-01-01

    We evaluated community general education (CGE; n = 178), community special education (CSE; n = 30) and hospital-referred (HR, n = 145) children (ages 7-6 to 11-11) prospectively over a 2-year period. During this period, 17 CGE children were referred for evaluation (community referred; CR). Prior to referral, CR children performed more poorly than community-nonreferred (CNR) children on cognitive ability, academic achievement, attention problems, and information processing. CR group performance was equivalent to that of CSE and HR groups, but HR children showed poorer academic achievement. Referred children performed more poorly on all measures than nonreferred, whether they met formal diagnostic criteria for a learning disorder or not. Learning disorders may be better conceptualized as a context-dependent problem of functional adaptation than as a disability analogous to physical disabilities, raising questions about the validity of using psychometric test scores as the criterion for identification. PMID:15497490

  14. Assessing Social Competence and Behavior Problems in a Sample of Italian Preschoolers Using the Social Competence and Behavior Evaluation Scale

    ERIC Educational Resources Information Center

    Sette, Stefania; Baumgartner, Emma; MacKinnon, David P.

    2015-01-01

    Research Findings: The main goals of this study were to examine the factor validity of the Social Competence and Behavior Evaluation (SCBE-30) scale using exploratory factor analysis and confirmatory factor analysis and to test factor invariance across gender in a sample of Italian preschool-age children (241 boys, 252 girls). The concurrent…

  15. Sex Differences in Childhood Sexual Abuse Characteristics and Victims' Emotional and Behavioral Problems: Findings from a National Sample of Youth

    ERIC Educational Resources Information Center

    Maikovich-Fong, Andrea Kohn; 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…

  16. Mental Disorders and Problem Behavior in a Community Sample of Adults with Intellectual Disability: Three-Month Prevalence and Comorbidity

    ERIC Educational Resources Information Center

    Hove, Oddbjorn; Havik, Odd E.

    2008-01-01

    The aim of this study was to investigate the prevalence of mental disorders in a Norwegian sample of adults with intellectual disability (ID) using the "Psychopathology Checklists for Adults With Intellectual Disability" (P-AID; Hove & Havik, 2008), a screening instrument adopting diagnostic criteria from the "Diagnostic Criteria for Psychiatric…

  17. The problem with medical research on tissue and organ samples taken in connection with forensic autopsies in France.

    PubMed

    Rougé-Maillart, C; Dupont, V; Jousset, N

    2016-02-01

    Currently, in France, it is legally impossible to conduct scientific research on tissue and organ samples taken from forensic autopsies. In fact, the law schedules the destruction of such samples at the end of the judicial investigation, and the common law rules governing cadaver research cannot be applied to the forensic context. However, nothing seems in itself to stand in the way of such research since, despite their specific nature, these samples from forensic autopsies could be subject, following legislative amendments, to common law relating to medical research on samples taken from deceased persons. But an essential legislative amendment, firstly to allow the Biomedicine Agency to become authorized to issue a research permit and secondly, to change the research conditions in terms of the non-opposition of the deceased to said research. Such an amendment would be a true breakthrough because it would allow teams to continue to move forward calmly in research, and allow this research to be placed within a legal framework, which would promote international exchanges. PMID:26694871

  18. A Multidimensional Model of Adolescent Drug Involvement.

    ERIC Educational Resources Information Center

    Herting, Jerald R.; And Others

    1996-01-01

    Tested a multidimensional model of adolescent drug involvement on samples of high school students. Focused on five first-order dimensions: drug access, alcohol use, other drug use, drug control problems, and adverse drug use consequences. Results contributed to understanding differences and change in drug involvement among high-risk versus…

  19. The effects of parental sensitivity and involvement in caregiving on mother-infant and father-infant attachment in a Portuguese sample.

    PubMed

    Fuertes, Marina; Faria, Anabela; Beeghly, Marjorie; Lopes-Dos-Santos, Pedro

    2016-02-01

    In the present longitudinal study, we investigated attachment quality in Portuguese mother-infant and in father-infant dyads, and evaluated whether attachment quality was related to parental sensitivity during parent-infant social interaction or to the amount of time each parent spent with the infant during play and in routine caregiving activities (e.g., feeding, bathing, play). The sample consisted of 82 healthy full-term infants (30 girls, 53 boys, 48 first born), and their mothers and fathers from mostly middle-class households. To assess parental sensitivity, mothers and fathers were independently observed during free play interactions with their infants when infants were 9 and 15 months old. The videotaped interactions were scored by masked coders using the Crittenden's CARE-Index. When infants were 12 and 18 months old, mother-infant and father-infant dyads were videotaped during an adaptation of Ainsworth's Strange Situation. Parents also described their level of involvement in infant caregiving activities using a Portuguese version of the McBride and Mills Parent Responsibility Scale. Mothers were rated as being more sensitive than fathers during parent-infant free play at both 9 and 15 months. There also was a higher prevalence of secure attachment in mother-infant versus father-infant dyads at both 12 and 18 months. Attachment security was predicted by the amount of time mothers and fathers were involved in caregiving and play with the infant, and with parents' behavior during parent-infant free play. (PsycINFO Database Record PMID:26437145

  20. Health and Social Problems Associated with Prescription Opioid Misuse Among a Diverse Sample of High Risk Substance-Using MSM

    PubMed Central

    Buttram, Mance E.; Kurtz, Steven P.; Surratt, Hilary L.; Levi-Minzi, Maria A.

    2013-01-01

    This study examines associations between prescription opioid misuse and demographics, substance use, sexual behavior, and related health and social problems. Baseline data were collected between 2008 and 2010 from 515 high risk men who have sex with men (MSM), ages 18–55, in the Miami-Ft. Lauderdale metropolitan area who reported heavy substance use and HIV risk in the past 90 days. Prescription opioid misuse was associated with other substance use, drug injection, substance dependence, and history of arrest. Implications, limitations, and directions for future study are discussed. PMID:23971894

  1. Relationship of attention-deficit/hyperactivity disorder symptom severity with severity of alcohol-related problems in a sample of inpatients with alcohol use disorder

    PubMed Central

    Bozkurt, Muge; Evren, Cuneyt; Umut, Gokhan; Evren, Bilge

    2016-01-01

    Purpose Attention-deficit/hyperactivity disorder (ADHD) has been shown to be related to a higher risk of developing psychiatric problems such as depressive disorders, substance use disorder, and impulsivity. Adults who have comorbid ADHD and alcohol use disorder (AUD) are at greater risk of negative outcomes. Thus, it is important to evaluate the relationship of ADHD symptoms and the severity of alcohol-related problems among patients with AUD. The aim of the present study was to evaluate the effect of ADHD symptoms on severity of alcohol-related problems, while controlling the effects of depression and impulsivity in a sample of inpatients with AUD. Patients and methods Participants (n=190) were evaluated with the Beck Depression Inventory, the Short Form Barratt Impulsiveness Scale, the Michigan Alcohol Screening Test, and the Adult ADHD Self-Report Scale. Results Severity of the scale scores was positively correlated with each other. Although severity of depression and impulsivity (particularly non-planning impulsivity) predicted the severity of alcohol-related problems in a linear regression model, when severity of ADHD symptoms was included in the analysis, the inattentive subscale score, in particular, predicted the severity of alcohol-related problems together with non-planning impulsivity, whereas depression was no longer a predictor. Conclusion These findings suggest that, together with non-planning impulsivity, symptoms of ADHD (particularly inattentive factor) are an important factor that predict alcohol-related problems, while controlling the severity of depressive symptoms among inpatients with AUD. PMID:27462159

  2. Multivariate Analysis, Retrieval, and Storage System (MARS). Volume 6: MARS System - A Sample Problem (Gross Weight of Subsonic Transports)

    NASA Technical Reports Server (NTRS)

    Hague, D. S.; Woodbury, N. W.

    1975-01-01

    The Mars system is a tool for rapid prediction of aircraft or engine characteristics based on correlation-regression analysis of past designs stored in the data bases. An example of output obtained from the MARS system, which involves derivation of an expression for gross weight of subsonic transport aircraft in terms of nine independent variables is given. The need is illustrated for careful selection of correlation variables and for continual review of the resulting estimation equations. For Vol. 1, see N76-10089.

  3. STEALTH: a Lagrange explicit finite difference code for solids, structural, and thermohydraulic analysis. Volume 2: sample and verification problems. Computer code manual. [PWR; BWR

    SciTech Connect

    Hofmann, R.

    1982-08-01

    STEALTH sample and verification problems are presented to help users become familiar with STEALTH capabilities, input, and output. Problems are grouped into articles which are completely self-contained. The pagination in each article is A.n, where A is a unique alphabetic-character article identifier and n is a sequential page number which starts from 1 on the first page of text for each article. Articles concerning new capabilities will be added as they become available. STEALTH sample and verification calculations are divided into the following general categories: transient mechanical calculations dealing with solids; transient mechanical calculations dealing with fluids; transient thermal calculations dealing with solids; transient thermal calculations dealing with fluids; static and quasi-static calculations; and complex boundary interaction calculations.

  4. An empirical demonstration of the problem of cluster dissimilarity from different clustering methods in a single sample.

    PubMed

    Saltstone, R; Fraboni, M

    1990-11-01

    This study utilized the four most commonly employed clustering techniques (CLINK, SLINK, UPGMA, and Ward's) to illustrate the dissimilarity of cluster group membership (based upon short-form MMPI scale scores and a measure of alcohol dependency) between partitions in a sample of 113 impaired driving offenders. Results, examined with the Rand index of cluster comparison, demonstrated that cluster group membership can be so different between alternative clustering methods as to equal chance assignment. Cautions are given with regard to the use of cluster analysis for other than exploratory work. In particular, psychologists are cautioned against attempting to use cluster analysis based upon personality inventory scores (which can never be wholly reliable or discrete) for patient classification. PMID:2286695

  5. The Clark Phase-able Sample Size Problem: Long-Range Phasing and Loss of Heterozygosity in GWAS

    NASA Astrophysics Data System (ADS)

    Halldórsson, Bjarni V.; Aguiar, Derek; Tarpine, Ryan; Istrail, Sorin

    A phase transition is taking place today. The amount of data generated by genome resequencing technologies is so large that in some cases it is now less expensive to repeat the experiment than to store the information generated by the experiment. In the next few years it is quite possible that millions of Americans will have been genotyped. The question then arises of how to make the best use of this information and jointly estimate the haplotypes of all these individuals. The premise of the paper is that long shared genomic regions (or tracts) are unlikely unless the haplotypes are identical by descent (IBD), in contrast to short shared tracts which may be identical by state (IBS). Here we estimate for populations, using the US as a model, what sample size of genotyped individuals would be necessary to have sufficiently long shared haplotype regions (tracts) that are identical by descent (IBD), at a statistically significant level. These tracts can then be used as input for a Clark-like phasing method to obtain a complete phasing solution of the sample. We estimate in this paper that for a population like the US and about 1% of the people genotyped (approximately 2 million), tracts of about 200 SNPs long are shared between pairs of individuals IBD with high probability which assures the Clark method phasing success. We show on simulated data that the algorithm will get an almost perfect solution if the number of individuals being SNP arrayed is large enough and the correctness of the algorithm grows with the number of individuals being genotyped.

  6. Sample Preparation Problem Solving for Inductively Coupled Plasma-Mass Spectrometry with Liquid Introduction Systems I. Solubility, Chelation, and Memory Effects

    PubMed Central

    Pappas, R. Steven

    2015-01-01

    This tutorial was adapted from the first half of a course presented at the 7th International Conference on Sector Field Inductively Coupled Plasma Mass Spectrometry in 2008 and the 2012 Winter Conference on Plasma Spectrochemistry on sample preparation for liquid introduction systems. Liquid introduction in general and flow injection specifically are the most widely used sample introduction methods for inductively coupled plasma-mass spectrometry. Nevertheless, problems persist in determination of analytes that are commonly investigated, as well as in specialty applications for those seldom considered by most analysts. Understanding the chemistry that is common to different groups of analytes permits the development of successful approaches to rinse-out and elimination of memory effects. This understanding also equips the analyst for development of successful elemental analytical approaches in the face of a broad spectrum of matrices and other analytical challenges, whether the sample is solid or liquid. PMID:26321788

  7. Problems in Determination of Skeletal Lead Burden in Archaeological Samples: An Example From the First African Baptist Church Population

    SciTech Connect

    Whittmers Jr., L. E.; Aufderheide, A. C.; Pounds, Joel G.; JONES, Keith; Angel, J. L.

    2008-08-01

    ABSTRACT Human bone lead content has been demonstrated to be related to socioeconomic status, occupation and other social and environmental correlates. Skeletal tissue samples from 135 individuals from an early nineteenth century Philadelphia cemetery (First African Baptist Church) were studied by electrothermal atomic absorption spectrometry and x-ray fluorescence for lead content. High bone lead levels led to investigation of possible diagenetic effects. These were investigated by several different approaches including distribution of lead within bone by x-ray fluorescence, histological preservation, soil lead concentration and acidity as well as location and depth of burial. Bone lead levels were very high in children, exceeding those of the adult population that were buried in the cemetery, and also those of present day adults. The antemortem age-related increase in bone lead, reported in other studies, was not evidenced in this population. Lead was even deposited in areas of taphonomic bone destruction. Synchrotron x-ray fluorescence studies revealed no consistent pattern of lead microdistribution within the bone. Our conclusions are that postmortem diagenesis of lead ion has penetrated these archaeological bones to a degree that makes their original bone lead content irretrievable by any known method. Increased bone porosity is most likely responsible for the very high levels of lead found in bones of newborns and children.

  8. Problems in determination of skeletal lead burden in archaeological samples: An example from the First African Baptist Church population

    SciTech Connect

    Whittmers Jr., L. E.; Aufderheide, A. C.; Pounds, Joel G.; Jones, Keith W.; Angel, J. L.

    2008-08-01

    Human bone lead content has been demonstrated to be related to socioeconomic status, occupation and other social and environmental correlates. Skeletal tissue samples from 135 individuals from an early nineteenth century Philadelphia cemetery (First African Baptist Church) were studied by electrothermal atomic absorption spectrometry and x-ray fluorescence for lead content. High bone lead levels led to investigation of possible diagenetic effects. These were investigated by several different approaches including distribution of lead within bone by x-ray fluorescence, histological preservation, soil lead concentration and acidity as well as location and depth of burial. Bone lead levels were very high in the children, exceeding those of the adult population that were buried in the cemetery, and also those of present day adults. The antemortem age-related increase in bone lead, reported in other studies, was not evidenced in this population. Lead was even deposited in areas of taphonomic bone destruction. Synchrotron x-ray fluorescence studies revealed no consistent pattern of lead microdistribution within the bone. Our conclusions are that postmortem diagenesis of lead ion has penetrated these archaeological bones to a degree that makes their original bone lead content irretrievable by any known method. Increased bone porosity is most likely responsible for the very high levels of lead found in bones of newborns and children.

  9. Problems in determination of skeletal lead burden in archaeological samples: an example from the First African Baptist Church population.

    PubMed

    Wittmers, L E; Aufderheide, A C; Pounds, J G; Jones, K W; Angel, J L

    2008-08-01

    Human bone lead content has been demonstrated to be related to socioeconomic status, occupation and other social and environmental correlates. Skeletal tissue samples from 135 individuals from an early nineteenth century Philadelphia cemetery (First African Baptist Church) were studied by electrothermal atomic absorption spectrometry and X-ray fluorescence for lead content. High bone lead levels led to investigation of possible diagenetic effects. These were investigated by several different approaches including distribution of lead within bone by X-ray fluorescence, histological preservation, soil lead concentration and acidity as well as location and depth of burial. Bone lead levels were very high in children, exceeding those of the adult population that were buried in the cemetery, and also those of present day adults. The antemortem age-related increase in bone lead, reported in other studies, was not evidenced in this population. Lead was evenly deposited in areas of taphonomic bone destruction. Synchrotron X-ray fluorescence studies revealed no consistent pattern of lead microdistribution within the bone. Our conclusions are that postmortem diagenesis of lead ion has penetrated these archaeological bones to a degree that makes their original bone lead content irretrievable by any known method. Increased bone porosity is most likely responsible for the very high levels of lead found in bones of newborns and children. PMID:18386797

  10. SIPPI: A Matlab toolbox for sampling the solution to inverse problems with complex prior information. Part 2—Application to crosshole GPR tomography

    NASA Astrophysics Data System (ADS)

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

    2013-03-01

    We present an application of the SIPPI Matlab toolbox, to obtain a sample from the a posteriori probability density function for the classical tomographic inversion problem. We consider a number of different forward models, linear and non-linear, such as ray based forward models that rely on the high frequency approximation of the wave-equation and 'fat' ray based forward models relying on finite frequency theory. In order to sample the a posteriori probability density function we make use of both least squares based inversion, for linear Gaussian inverse problems, and the extended Metropolis sampler, for non-linear non-Gaussian inverse problems. To illustrate the applicability of the SIPPI toolbox to a tomographic field data set we use a cross-borehole traveltime data set from Arrenæs, Denmark. Both the computer code and the data are released in the public domain using open source and open data licenses. The code has been developed to facilitate inversion of 2D and 3D travel time tomographic data using a wide range of possible a priori models and choices of forward models.

  11. Psychiatric Stigma in Treatment-Seeking Adults with Personality Problems: Evidence from a Sample of 214 Patients

    PubMed Central

    Catthoor, Kirsten; Schrijvers, Didier; Hutsebaut, Joost; Feenstra, Dineke; Sabbe, Bernard

    2015-01-01

    Stigmatization is a major burden in adult psychiatric patients with Axis-I diagnoses, as shown consistently in most studies. Significantly fewer studies on the emergence of psychiatric stigma in adult patients with personality disorders (PDs) exist, although the resulting evidence is conclusive. Some authors consider patients with PDs at risk for severe stigmatization because of intense difficulties during interpersonal contact, even in a psychotherapeutic relationship. The aim of this study was primarily the assessment of pre-existing stigma in patients referred for intensive treatment for PDs. The study enrolled 214 patients admitted to the adult department of a highly specialized mental health care institute offering psychotherapy for patients with severe and complex personality pathology. All patients underwent a standard assessment with self-report questionnaires and a semi-structured interview to measure Axis II PDs. The stigma consciousness questionnaire and the perceived devaluation-discrimination questionnaire, both validated instruments, were used to measure perceived and actual experiences of stigma. Independent sample t-tests were used to investigate differences in the mean total stigma scores for patients both with and without a PD. One-way ANOVAs were performed to assess the differences between having a borderline PD, another PD, or no PD diagnosis. Multiple regression main effect analyses were conducted in order to explore the impact of the different PD diagnosis on the level of stigma. The mean scores across all patient groups were consistent with rather low stigma. No differences were found for patients with or without a PD diagnosis. Level of stigma in general was not associated with an accumulating number of PDs. Given the remarkable results, we would strongly recommend further investigations in the field to better understand the phenomenon of stigma in all its aspects. PMID:26217243

  12. Temperamental predictors of externalizing problems among boys and girls: a longitudinal study in a high-risk sample from ages 3 months to 15 years.

    PubMed

    Pitzer, Martina; Esser, Guenter; Schmidt, Martin H; Laucht, Manfred

    2009-12-01

    In a high-risk community sample, we examined the role of regulative temperament and emotionality as well as the extent of gender specificity in the development of externalizing problems. 151 boys and 157 girls born at differing degrees of obstetric and psychosocial risk were followed from birth into adolescence. In infancy and childhood, NYLS-derived temperamental characteristics were assessed by a highly structured parent interview and standardized behavioral observations. At age 15 years, externalizing problems were measured by the Child Behavior Checklist. As revealed by multiple linear regression and logistic regression, low regulative abilities predicted adolescent behavioral and attentional problems over and above obstetric and psychosocial risks. Gender specificity was found in the strength of the association rather than in the kind with a stronger long-term prediction from infant and toddler temperament in girls. Compared to regulative abilities, temperament factors describing aspects of mood and fear/withdrawal versus approach tendencies played a minor role in the development of externalizing problems. Findings are discussed in terms of gender-specific risk factors and possible differential developmental trajectories to subtypes of disruptive behavior. PMID:19387718

  13. Histories of childhood victimization and subsequent mental health problems, substance use, and sexual victimization for a sample of incarcerated women in the US.

    PubMed

    Tripodi, Stephen J; Pettus-Davis, Carrie

    2013-01-01

    Women are entering US prisons at nearly double the rate of men and are the fastest growing prison population. Current extant literature focuses on the prevalence of the incarceration of women, but few studies exist that emphasize the different trajectories to prison. For example, women prisoners have greater experiences of prior victimization, more reports of mental illness, and higher rates of illicit substance use. The purpose of this study was to understand the prevalence of childhood victimization and its association with adult mental health problems, substance abuse disorders, and further sexual victimization. The research team interviewed a random sample of 125 women prisoners soon to be released from prison to gather information on their childhood physical and sexual victimization, mental health and substance abuse problems as an adult, and sexual victimization in the year preceding incarceration. Results indicate that women prisoners in this sample, who were both physically and sexually victimized as children, were more likely to be hospitalized as an adult for a psychological or emotional problem. Women who were sexually victimized or both physically and sexually victimized were more likely to attempt suicide. Women who experienced physical victimization as children and women who were both physically and sexually victimized were more likely to have a substance use disorder and women who were sexually abused as children or both physically and sexually victimized were more likely to be sexually abused in the year preceding prison. This article ends with a discussion about prisons' role in providing treatment for women prisoners and basing this treatment on women's trajectories to prison, which disproportionately include childhood victimization and subsequent mental health and substance use problems. PMID:23196054

  14. The Effect of Teacher's Invitations to Parental Involvement on Children's Externalizing Problem Behaviors: An Examination of a CBC Intervention. CYFS Working Paper No. 2012-3

    ERIC Educational Resources Information Center

    Coutts, Michael J.; Sheridan, Susan M.; Kwon, Kyongboon; Semke, Carrie A.

    2012-01-01

    Behavioral problems in childhood are associated with academic difficulties including in-school suspensions, high school dropout, and low academic grades and achievement scores. Students with disruptive behavior problems demonstrate higher rates of social risk factors than their nondisruptive peers, including school maladjustment, antisocial…

  15. Forcible, drug-facilitated, and incapacitated rape in relation to substance use problems: results from a national sample of college women.

    PubMed

    McCauley, Jenna; Ruggiero, Kenneth J; Resnick, Heidi S; Conoscenti, Lauren M; Kilpatrick, Dean G

    2009-05-01

    This is the first study to examine the relation between rape and substance use problems in college women as a function of three legally recognized forms of rape: forcible, incapacitated, and substance-facilitated rape. Data were collected via structured telephone interview with a large national sample of college women aged 18-34 years (n=1980). Lifetime prevalence of any type of rape was 11.3% in the sample. Prevalence estimates for binge drinking and substance abuse were 15.8% and 19.8%, respectively. Lifetime experience of incapacitated rape and drug-alcohol facilitated rape, but not forcible rape, were associated with increased odds of past-year binge drinking and substance abuse. Findings have implications for secondary prevention and call for continued differentiation in assessment of rape type. PMID:19162407

  16. Do adolescent drug use consequences predict externalizing and internalizing problems in emerging adulthood as well as traditional drug use measures in a Hispanic sample?

    PubMed

    Grigsby, Timothy J; Forster, Myriam; Baezconde-Garbanati, Lourdes; Soto, Daniel W; Unger, Jennifer B

    2014-03-01

    The present study compares statistical models for three conceptualizations of drug use in 11th grade (past 30 day ever/never use, past 30 day frequency of drug use and past 30 day drug use consequences) with externalizing and internalizing problems in emerging adulthood when controlling for age, academic achievement and socioeconomic status in a Hispanic sample. Multivariate logistic regression models for the different drug use variables were compared when modeling weapon carrying, arrest, multiple lifetime sex partners, drug/alcohol use before sex and condom use in emerging adulthood. A multivariate linear regression model was used to model depression in emerging adulthood as a function of drug use measurement controlling for other covariates and depression in adolescence. Our findings suggest that any conceptualization of drug use will produce equitable results and model fit statistics when examining externalizing problems. However, when investigating internalizing problems, such as depression, lower frequency drug use-and not high frequency-was more strongly associated with depression whereas experiencing high levels of drug use consequences-and not low levels of consequences-was associated with depression in emerging adulthood despite similar model fit values. Variation between drug use and the experience of drug use consequences may lead to misspecification of "at-risk" subgroups of drug users. Implications and future directions are discussed. PMID:24345310

  17. Do adolescent drug use consequences predict externalizing and internalizing problems in emerging adulthood as well as traditional drug use measures in a Hispanic sample?

    PubMed Central

    Grigsby, Timothy J.; Forster, Myriam; Baezconde-Garbanati, Lourdes; Soto, Daniel W.; Unger, Jennifer B.

    2014-01-01

    The present study compares statistical models for three conceptualizations of drug use in 11th grade (past 30 day ever/never use, past 30 day frequency of drug use and past 30 day drug use consequences) with externalizing and internalizing problems in emerging adulthood when controlling for age, academic achievement and socioeconomic status in a Hispanic sample. Multivariate logistic regression models for the different drug use variables were compared when modeling weapon carrying, arrest, multiple lifetime sex partners, drug/alcohol use before sex and condom use in emerging adulthood. A multivariate linear regression model was used to model depression in emerging adulthood as a function of drug use measurement controlling for other covariates and depression in adolescence. Our findings suggest that any conceptualization of drug use will produce equitable results and model fit statistics when examining externalizing problems. However, when investigating internalizing problems, such as depression, lower frequency drug use—and not high frequency—was more strongly associated with depression whereas experiencing high levels of drug use consequences—and not low levels of consequences—was associated with depression in emerging adulthood despite similar model fit values. Variation between drug use and the experience of drug use consequences may lead to misspecification of “at-risk” subgroups of drug users. Implications and future directions are discussed. PMID:24345310

  18. Issues involved in a Martian sample return: Integrity preservation and the Curation and Analysis Planning Team for Extraterrestrial Materials (CAPTEM) position

    NASA Astrophysics Data System (ADS)

    Neal, Clive R.

    2000-09-01

    Returning geological samples from Mars is the next logical step as part of an integrated exploration program and is the critical subsequent stage in the search for evidence of life on the red planet. Analysis of such samples on Earth will generally produce data of superior accuracy and precision than can be accomplished in situ on the Martian surface, and such data will be invaluable in providing ground truth for remotely sensed observations. However, obtaining meaningful data requires that the samples returned to Earth suffer little (or preferably no) compositional or morphological changes during collection on Mars, transit to Earth, entry into Earth's atmosphere, impact on the surface, and long-term curation. This paper presents recommendations from NASA's committee for Curation and Analysis Planning Team for Extraterrestrial Materials (CAPTEM) for preserving the integrity of Martian samples during a return mission. Potential contaminants include dead bacteria on the outbound spacecraft and materials that come into contact with the samples during collection and storage. Therefore it is recommended that the spacecraft be sterilized and cleaned at least to Pathfinder standards, with the components that interact with the samples having a higher degree of cleanliness. Furthermore, it is recommended that only pure, homogeneous materials should be used for components that come into contact with the samples. The adverse effects of temperature on the samples are explored, and it is demonstrated that heat sterilization or undue temperature increases in transit or reentry have the potential to destroy important mineralogical and geochemical information. Concomitant with this will be degassing of the samples and stable isotopic fractionation. Therefore it is recommended that samples be kept at 240 K or below during transit, reentry, and curation. It is further recommended that heat sterilization not be used, except in extreme circumstances, and other sterilization

  19. Association of socioeconomic status with psychiatric problems and violent behaviours in a nationally representative sample of Iranian children and adolescents: the CASPIAN-IV study

    PubMed Central

    Heshmat, Ramin; Qorbani, Mostafa; Ghoreshi, Behnaz; Djalalinia, Shirin; Tabatabaie, Omid Reza; Safiri, Saeid; Noroozi, Mehdi; Motlagh, Mohammad-Esmaeil; Ahadi, Zeinab; Asayesh, Hamid; Kelishadi, Roya

    2016-01-01

    Objectives The aim of the present study was to evaluate the association between socioeconomic status (SES) and psychiatric problems and violent behaviours in a nationally representative sample of Iranian children and adolescents, based on nationwide surveillance programme data, 2011–2012. Methods Overall, 14 880 students, aged 6–18 years, were selected using a multistage cluster sampling method from rural and urban areas of 30 provinces in Iran. SES was estimated based on a main summarised component, extracted from principle component analysis of family assets and parents' jobs and education. For statistical analysis, SES was classified as ‘low’, ‘middle’ and ‘high’. The WHO-Global School Based Student Health Survey (WHO-GSHS) questionnaire was used to assess psychiatric problems and violent behaviours. Results In total, 13 486 students (participation rate 90.6%) completed the study: 50.8% were boys and 75.6% were urban residents, with a mean age of 12.47±3.36 years. In the multivariate model, the ORs of depression, anxiety, feeling worthless, anger, insomnia, confusion and physical fights were lower in students with high SES compared with those with low SES (p<0.05) but physical fights was lower in the high SES group than in the low SES group (p<0.05). No significant relationship was documented between SES and other variables, including getting worried, history of bullying and being victimised. Conclusions Children and adolescents with low SES were at higher risk for psychiatric problems and violent behaviours. Mental health policies and public interventional strategies should be considered at the public level, notably for low SES families. PMID:27531729

  20. What are some of the cognitive, psychological, and social factors that facilitate or hinder licensed vocational nursing students' acquisition of problem-solving skills involved with medication-dosage calculations?

    NASA Astrophysics Data System (ADS)

    Allen, Arthur William

    The purpose of this study was to examine the cognitive and psychological factors that either enhanced or inhibited Licensed Vocational Nurse (LVN) students' abilities to solve medication-dosage calculation problems. A causal-comparative approach was adopted for use in this study which encompassed aspects of both qualitative and quantitative data collection. A purposive, maximum-variation sample of 20 LVN students was chosen from among a self-selected population of junior college LVN students. The participants' views and feelings concerning their training and clinical experiences in medication administration was explored using a semi-structured interview. In addition, data revealing the students' actual competence at solving sample medication-dosage calculation problems was gathered using a talk-aloud protocol. Results indicated that few participants anticipated difficulty with medication-dosage calculations, yet many participants reported being lost during much of the medication-dosage problem solving instruction in class. While many participants (65%) were able to solve the medication-dosage problems, some (35%) of the participants were unable to correctly solve the problems. Successful students usually spent time analyzing the problem and planning a solution path, and they tended to solve the problem faster than did unsuccessful participants. Successful participants relied on a formula or a proportional statement to solve the problem. They recognized conversion problems as a two-step process and solved the problems in that fashion. Unsuccessful participants often went directly from reading the problem statement to attempts at implementing vague plans. Some unsuccessful participants finished quickly because they just gave up. Others spent considerable time backtracking by rereading the problem and participating in aimless exploration of the problem space. When unsuccessful participants tried to use a formula or a proportion, they were unsure of the formula's or

  1. A Handbook for University-Community Discussion of Urban Problems. A Model for Urban Study Programs Involving College Students and Community Adults.

    ERIC Educational Resources Information Center

    Coplin, William, Comp.; Cohen, Larry, Comp.

    Techniques employed in a "Joint University-Community Urban Problem-Solving Course" in promoting discussion among two diverse sets of population are described in this handbook. The course, offered during the Fall 1971 and Spring 1972 semesters at Syracuse University, comprised approximately 30 undergraduates from the university and 30 members of…

  2. Implementation of the Bacillus cereus microbiological plate used for the screening of tetracyclines in raw milk samples with STAR protocol - the problem with false-negative results solved.

    PubMed

    Raspor Lainšček, P; Biasizzo, M; Henigman, U; Dolenc, J; Kirbiš, A

    2014-01-01

    In antibiotic residue analyses the first step of screening is just as important as the following steps. Screening methods need to be quick and inexpensive, but above all sensitive enough to detect the antibiotic residue at or below the maximum residue limit (MRL). In the case of a positive result, the next step is conducted and further methods are used for confirmation. MRLs stated in European Union Regulation 37/2010 for tetracyclines in raw milk are: 100 µg kg(-1) for tetracycline, 100 µg kg(-1) for oxytetracycline, 100 µg kg(-1) for chlortetracycline and no limit for doxycycline because it is prohibited for use in animals from which milk is produced for human consumption. The current five-plate microbiological screening method for the detection of antibiotic residues in raw milk was found to be simple and inexpensive, but not specific, sensitive and reliable enough to detect tetracycline at MRL in routine raw milk screening procedures. Spiking samples with tetracycline at the MRL level and applying them on Bacillus cereus ATCC 11778 microbiological plates often gave false-negative results, indicating that tetracyclines may have to be inactivated or masked. Tetracyclines seem to bind to a certain component in milk. Consequently, when applying samples to the B. cereus microbiological plate the antibiotic cannot inhibit the growth of B. cereus which disables the formation of inhibition zones on the test plate. After adding the appropriate amount of citric acid into the milk samples, we solved the problem of false-negative results. During the validation 79 samples of milk were spiked with tetracyclines at different concentrations: 100 µg kg(-1) for tetracycline, 100 µg kg(-1) for oxytetracycline, 80 µg kg(-1) for chlortetracycline and 30 µg kg(-1) for doxycycline. Concentrations used in the validation matched the requirements for MRLs (they were either at or below the MRLs) stated in European Union Regulation 37/2010. The sensitivity of the validation was 100

  3. Tourette Syndrome: Overview and Classroom Interventions. A Complex Neurobehavioral Disorder Which May Involve Learning Problems, Attention Deficit Hyperactivity Disorder, Obsessive Compulsive Symptoms, and Stereotypical Behaviors.

    ERIC Educational Resources Information Center

    Fisher, Ramona A.; Collins, Edward C.

    Tourette Syndrome is conceptualized as a neurobehavioral disorder, with behavioral aspects that are sometimes difficult for teachers to understand and deal with. The disorder has five layers of complexity: (1) observable multiple motor, vocal, and cognitive tics and sensory involvement; (2) Attention Deficit Hyperactivity Disorder; (3)…

  4. Sample taking problems in measuring actual histamine levels of human gastroduodenal mucosa: specific and general relevance in clinical trials on peptic ulcer pathogenesis and selective proximal vagotomy.

    PubMed Central

    Thon, K P; Lorenz, W; Ohmann, C; Weber, D; Rohde, H; Röher, H D

    1985-01-01

    Changes in histamine storage in the oxyntic mucosa of duodenal ulcer patients and their reversal by vagotomy and the histamine H2-antagonist cimetidine supported the hypothesis that histamine could be a causal factor in peptic ulcer pathogenesis. The specificity of these findings was impaired by problems in biopsy taking, however, and in the preparative steps before measuring the actual histamine contents in all parts of the gastric mucosa and in the duodenum. A prospective trial was carried out in 190 patients to identify these sources of bias and to overcome them by appropriate study designs. Usually a direct correlation was found between weight of biopsy and mucosal histamine content. This problem was solved by selecting a biopsy forceps producing smaller variations in sample size, by limiting the time of cold ischaemia to four to five minutes only and by taking three biopsy specimens for each single histamine value. The actual histamine content of mucosal biopsies remained constant for about four to five minutes only. The 'disappearance' rate was faster in control subjects than in duodenal ulcer patients. Hence by variation of the cold ischaemia time any artefacts of differences between mucosal histamine levels in controls and duodenal ulcer patients could be produced. Using the optimised sample taking procedure mucosal histamine contents of several gastric regions and the duodenal bulb were measured in 24 patients with duodenal ulcer, after selective proximal vagotomy without drainage and in control subjects without any stomach disease (randomised controlled trial). The histamine content was lower in all parts of the upper gastrointestinal tract in duodenal ulcer patients than in controls and was raised again in all regions after selective proximal vagotomy. As the most likely hypothesis it is suggested that vagal reflexes with afferent fibres coming from the oxyntic mucosa stimulate histamine release in duodenal ulcer patients by efferent peptidergic neurones

  5. Prevalence of mental health problems, treatment need, and barriers to care among primary care-seeking spouses of military service members involved in Iraq and Afghanistan deployments.

    PubMed

    Eaton, Karen M; Hoge, Charles W; Messer, Stephen C; Whitt, Allison A; Cabrera, Oscar A; McGurk, Dennis; Cox, Anthony; Castro, Carl A

    2008-11-01

    Military spouses must contend with unique issues such as a mobile lifestyle, rules and regulations of military life, and frequent family separations including peacekeeping and combat deployments. These issues may have an adverse effect on the health of military spouses. This study examined the mental health status, rates of care utilization, source of care, as well as barriers and stigma of mental health care utilization among military spouses who were seeking care in military primary care clinics. The data show spouses have similar rates of mental health problems compared to soldiers. Spouses were more likely to seek care for their mental health problems and were less concerned with the stigma of mental health care than were soldiers. Services were most often received from primary care physicians, rather than specialty mental health professionals, which may relate to the lack of availability of mental health services for spouses on military installations. PMID:19055177

  6. Grievance Procedure Problems.

    ERIC Educational Resources Information Center

    Green, Gary J.

    This paper presents two actual problems involving grievance procedures. Both problems involve pending litigation and one of them involves pending arbitration. The first problem occurred in a wealthy Minnesota school district and involved a seniority list. Because of changes in the financial basis for supporting public schools, it became necessary…

  7. On-line sample processing involving microextraction techniques as a front-end to atomic spectrometric detection for trace metal assays: a review.

    PubMed

    Miró, Manuel; Hansen, Elo Harald

    2013-06-11

    Within the last decade, liquid-phase microextraction (LPME) and micro-solid phase extraction (μSPE) approaches have emerged as substitutes for conventional sample processing procedures for trace metal assays within the framework of green chemistry. This review surveys the progress of the state of the art in simplification and automation of microextraction approaches by harnessing to the various generations of flow injection (FI) as a front end to atomic absorption spectrometry (AAS), atomic fluorescence spectrometry (AFS) or inductively coupled plasma atomic emission spectrometry or mass spectrometry (ICP-AES/MS). It highlights the evolution of flow injection analysis and related techniques as vehicles for appropriate sample presentation to the detector and expedient on-line matrix separation and pre-concentration of trace levels of metals in troublesome matrices. Rather than being comprehensive this review is aimed at outlining the pros and cons via representative examples of recent attempts in automating green sample preparation procedures in an FI or sequential injection (SI) mode capitalizing on single-drop microextraction, dispersive liquid-phase microextraction and advanced sorptive materials including carbon and metal oxide nanoparticles, ion imprinted polymers, superparamagnetic nanomaterials and biological/biomass sorbents. Current challenges in the field are identified and the synergetic combination of flow analysis, nanotechnology and metal-tagged biomolecule detection is envisaged. PMID:23708278

  8. Some Insights into Analytical Bias Involved in the Application of Grab Sampling for Volatile Organic Compounds: A Case Study against Used Tedlar Bags

    PubMed Central

    Ghosh, Samik; Kim, Ki-Hyun; Sohn, Jong Ryeul

    2011-01-01

    In this study, we have examined the patterns of VOCs released from used Tedlar bags that were once used for the collection under strong source activities. In this way, we attempted to account for the possible bias associated with the repetitive use of Tedlar bags. To this end, we selected the bags that were never heated. All of these target bags were used in ambient temperature (typically at or below 30°C). These bags were also dealt carefully to avoid any mechanical abrasion. This study will provide the essential information regarding the interaction between VOCs and Tedlar bag materials as a potential source of bias in bag sampling approaches. PMID:22235175

  9. Eastern oil shale research involving the generation of retorted and combusted oil shale solid waste, shale oil collection, and process stream sampling and characterization: Final report

    SciTech Connect

    Not Available

    1989-02-01

    Approximately 518 tons of New Albany oil shale were obtained from the McRae quarry in Clark County, Indiana and shipped to Golden, CO. A portion of the material was processed through a TOSCO II pilot plant retort. About 273 tons of crushed raw shale, 136 tons of retorted shale, 1500 gallons of shale oil, and 10 drums of retort water were shipped to US Department of Energy, Laramie, WY. Process conditions were documented, process streams were sampled and subjected to chemical analysis, and material balance calculations were made. 6 refs., 12 figs., 14 tabs.

  10. Some insights into analytical bias involved in the application of grab sampling for volatile organic compounds: a case study against used Tedlar bags.

    PubMed

    Ghosh, Samik; Kim, Ki-Hyun; Sohn, Jong Ryeul

    2011-01-01

    In this study, we have examined the patterns of VOCs released from used Tedlar bags that were once used for the collection under strong source activities. In this way, we attempted to account for the possible bias associated with the repetitive use of Tedlar bags. To this end, we selected the bags that were never heated. All of these target bags were used in ambient temperature (typically at or below 30°C). These bags were also dealt carefully to avoid any mechanical abrasion. This study will provide the essential information regarding the interaction between VOCs and Tedlar bag materials as a potential source of bias in bag sampling approaches. PMID:22235175

  11. Multiresidue determination of 256 pesticides in lavandin essential oil by LC/ESI/sSRM: advantages and drawbacks of a sampling method involving evaporation under nitrogen.

    PubMed

    Fillâtre, Yoann; Rondeau, David; Daguin, Antoine; Jadas-Hecart, Alain; Communal, Pierre-Yves

    2014-02-01

    The determination of 256 multiclass pesticides in lavandin essential oil has been performed by liquid chromatography-electrospray ionization tandem mass spectrometry using the scheduled selected reaction monitoring mode available on a quadrupole-linear ion trap mass spectrometer. With the aim of improving the limits of quantification (LOQs) of the target molecules, a sampling step based on evaporation of the essential oil under a nitrogen flow assisted by controlled heating was tested. The LOQs determined in this case were compared with the values obtained with the classic dilution preparation method. With sampling by dilution, 247 pesticides were detected and quantified at low concentration, with 74 % of the pesticides having LOQs of 10 μg L(-1) or less. With the evaporation method, a global improvement of the LOQs was observed, with lower LOQs for 92 active substances and LOQs of 10 μg L(-1) or less for 82.8 % of the pesticides. Almost twice as many active substances had an LOQ of 1 μg L(-1) or less when the evaporation method was used. Some pesticides exhibited poor recovery or high variance caused by volatilization or degradation during the evaporation step. This behavior was evidenced by the case of thiophanate-methyl, which is degraded to carbendazim. PMID:24366405

  12. Latent Class Analysis of Gambling Activities in a Sample of Young Swiss Men: Association with Gambling Problems, Substance Use Outcomes, Personality Traits and Coping Strategies.

    PubMed

    Studer, Joseph; Baggio, Stéphanie; Mohler-Kuo, Meichun; Simon, Olivier; Daeppen, Jean-Bernard; Gmel, Gerhard

    2016-06-01

    The study aimed to identify different patterns of gambling activities (PGAs) and to investigate how PGAs differed in gambling problems, substance use outcomes, personality traits and coping strategies. A representative sample of 4989 young Swiss males completed a questionnaire assessing seven distinct gambling activities, gambling problems, substance use outcomes, personality traits and coping strategies. PGAs were identified using latent class analysis (LCA). Differences between PGAs in gambling and substance use outcomes, personality traits and coping strategies were tested. LCA identified six different PGAs. With regard to gambling and substance use outcomes, the three most problematic PGAs were extensive gamblers, followed by private gamblers, and electronic lottery and casino gamblers, respectively. By contrast, the three least detrimental PGAs were rare or non-gamblers, lottery only gamblers and casino gamblers. With regard to personality traits, compared with rare or non-gamblers, private and casino gamblers reported higher levels of sensation seeking. Electronic lottery and casino gamblers, private gamblers and extensive gamblers had higher levels of aggression-hostility. Extensive and casino gamblers reported higher levels of sociability, whereas casino gamblers reported lower levels of anxiety-neuroticism. Extensive gamblers used more maladaptive and less adaptive coping strategies than other groups. Results suggest that gambling is not a homogeneous activity since different types of gamblers exist according to the PGA they are engaged in. Extensive gamblers, electronic and casino gamblers and private gamblers may have the most problematic PGAs. Personality traits and coping skills may predispose individuals to PGAs associated with more or less negative outcomes. PMID:25929440

  13. Self-help interventions for adjustment disorder problems: a randomized waiting-list controlled study in a sample of burglary victims.

    PubMed

    Bachem, Rahel; Maercker, Andreas

    2016-09-01

    Adjustment disorders (AjD) are among the most frequent mental disorders yet often remain untreated. The high prevalence, comparatively mild symptom impairment, and transient nature make AjD a promising target for low-threshold self-help interventions. Bibliotherapy represents a potential treatment for AjD problems. This study investigates the effectiveness of a cognitive behavioral self-help manual specifically directed at alleviating AjD symptoms in a homogenous sample of burglary victims. Participants with clinical or subclinical AjD symptoms following experience of burglary were randomized to an intervention group (n = 30) or waiting-list control group (n = 24). The new explicit stress response syndrome model for diagnosing AjD was applied. Participants received no therapist support and assessments took place at baseline, after the one-month intervention, and at three-month follow-up. Based on completer analyses, group by time interactions indicated that the intervention group showed more improvement in AjD symptoms of preoccupation and in post-traumatic stress symptoms. Post-intervention between-group effect sizes ranged from Cohen's d = .17 to .67 and the proportion of participants showing reliable change was consistently higher in the intervention group than in the control group. Engagement with the self-help manual was high: 87% of participants had worked through at least half the manual. This is the first published RCT of a bibliotherapeutic self-help intervention for AjD problems. The findings provide evidence that a low-threshold self-help intervention without therapist contact is a feasible and effective treatment for symptoms of AjD. PMID:27299909

  14. Race/ethnicity, sexual partnerships with men involved with drugs, and sexually transmitted infections among a sample of urban young adult women.

    PubMed

    Campbell, Leah F; Brown, Qiana; Cavanaugh, Courtenay; Lawson, April

    2015-10-01

    In many urban neighbourhoods in the United States, drug markets borne from disadvantage have produced risk for sexually transmitted infections through altered sexual norms and partnerships. Presently, we examined the association of race, sexual partnerships with men involved with drugs, and self-reported sexually transmitted infections among 240 African American and white women aged 18-30 years. Thirty seven per cent reported ever having a sexually transmitted infection. Almost 30% of Whites reported sex with a drug user, compared to 5% of African Americans. Fifty eight per cent of African Americans compared to 31% of Whites reported sex with a drug dealer. On Step 1 of a sequential logistic regression model, race was associated with lifetime sexually transmitted infections (OR = 4.7, 95% CI = 2.61-8.34). Results from the full sequential logistic regression model indicated a significant, but smaller association of race and lifetime sexually transmitted infections (Adjusted OR = 3.5, 95% CI = 1.78-7.02) and an association of sex with a drug dealer and lifetime sexually transmitted infections (Adjusted OR = 2.9, 95% CI = 1.55-5.20). Forming sexual partnerships with drug dealers may place women at increased risk for sexually transmitted infections and explain racial disparities. More research focused on drug dealers as core transmitters is needed. PMID:25505044

  15. Volunteer Bias in Recruitment, Retention, and Blood Sample Donation in a Randomised Controlled Trial Involving Mothers and Their Children at Six Months and Two Years: A Longitudinal Analysis

    PubMed Central

    Jordan, Sue; Watkins, Alan; Storey, Mel; Allen, Steven J.; Brooks, Caroline J.; Garaiova, Iveta; Heaven, Martin L.; Jones, Ruth; Plummer, Sue F.; Russell, Ian T.; Thornton, Catherine A.; Morgan, Gareth

    2013-01-01

    Background The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not. Methods and Results This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p<0.001). b) i)As the trial progressed, representation of the most deprived decreased. These participants and smokers were less likely to be retained at 6 months (n = 430[95%]) (OR 0.29,0.13–0.67 and 0.20,0.09–0.46), and 2 years (n = 380[84%]) (aOR 0.68,0.50–0.93 and 0.55,0.28–1.09), and consent to infant blood sample donation (n = 220[48%]) (aOR 0.72,0.57–0.92 and 0.43,0.22–0.83). ii)Mothers interested in probiotics or research or reporting infants’ adverse events or rashes were more likely to attend research clinics and consent to skin-prick testing. Mothers participating to help children were more likely to consent to infant blood sample donation. 2) In one trial outcome, atopic eczema, the intervention had a positive effect only in the over-represented, least deprived group. Here, data weighting attenuated risk reduction from 6.9%(0.9–13.1%) to 4.6%(−1.4–+10.5%), and OR from 0.40(0.18–0.91) to 0.56(0.26–1.21). Other findings were unchanged. Conclusions Potential for volunteer bias intensified during the trial, due to non

  16. A well-sampled phylogenetic analysis of the polystichoid ferns (Dryopteridaceae) suggests a complex biogeographical history involving both boreotropical migrations and recent transoceanic dispersals.

    PubMed

    Le Péchon, Timothée; Zhang, Liang; He, Hai; Zhou, Xin-Mao; Bytebier, Benny; Gao, Xin-Fen; Zhang, Li-Bing

    2016-05-01

    Intercontinental disjunctions in ferns have often been considered as the result of long-distance dispersal (LDD) events rather than of vicariance. However, in many leptosporangiate groups, both processes appear to have played a major role in shaping current geographical distribution. In this study, we reconstructed the phylogenetic relationships and inferred the ancestral distribution areas of the polystichoid ferns (Cyrtomium, Phanerophlebia, and Polystichum), to evaluate the relative impact of vicariance and LDD on the biogeography of this group. We used a molecular dataset including 3346 characters from five plastid loci. With 190 accessions our taxon coverage was about three times as large as any previous worldwide sampling. Biogeographical analyses were performed using S-DIVA and S-DEC and divergence times were estimated by integrating fossil and secondary calibrations. The polystichoid ferns are a monophyletic clade that may have originated in East Asia during the Eocene, an age much younger than previously estimated. Three transoceanic disjunctions between East Asia and New World were identified in the Paleogene: one for Phanerophlebia during late Eocene (34Ma, 19-51Ma), and two in Polystichum at the Eocene-Oligocene boundary (30Ma, 18-43Ma; 28Ma, 19-39Ma respectively). During the Neogene, further range expansions took place from Asia to Africa, Hawaii, and the Southwestern Indian Ocean region. Our results indicate that early transfers between the Old and the New World are compatible with a boreotropical migration scenario. After evolving in Asia during the Eocene, the polystichoid ferns reached the New World in independent migrations at the Eocene-Oligocene boundary through the boreotropical belt. However, although less likely, the alternative hypothesis of independent transoceanic dispersals from the Old to the New World cannot be ruled out. Further range expansion during the Neogene was most likely the result of long-distance dispersal (LDD). PMID

  17. Adaptive Peer Sampling with Newscast

    NASA Astrophysics Data System (ADS)

    Tölgyesi, Norbert; Jelasity, Márk

    The peer sampling service is a middleware service that provides random samples from a large decentralized network to support gossip-based applications such as multicast, data aggregation and overlay topology management. Lightweight gossip-based implementations of the peer sampling service have been shown to provide good quality random sampling while also being extremely robust to many failure scenarios, including node churn and catastrophic failure. We identify two problems with these approaches. The first problem is related to message drop failures: if a node experiences a higher-than-average message drop rate then the probability of sampling this node in the network will decrease. The second problem is that the application layer at different nodes might request random samples at very different rates which can result in very poor random sampling especially at nodes with high request rates. We propose solutions for both problems. We focus on Newscast, a robust implementation of the peer sampling service. Our solution is based on simple extensions of the protocol and an adaptive self-control mechanism for its parameters, namely—without involving failure detectors—nodes passively monitor local protocol events using them as feedback for a local control loop for self-tuning the protocol parameters. The proposed solution is evaluated by simulation experiments.

  18. Different stability of social-communication problems and negative demanding behaviour from infancy to toddlerhood in a large Dutch population sample

    PubMed Central

    2014-01-01

    Background Little is known about the stability of behavioural and developmental problems as children develop from infants to toddlers in the general population. Therefore, we investigated behavioural profiles at two time points and determined whether behaviours are stable during early development. Methods Parents of 4,237 children completed questionnaires with 62 items about externalizing, internalizing, and social-communicative behaviour when the children were 14–15 and 36–37 months old. Factor mixture modelling identified five homogeneous profiles at both time points: three with relatively normal behaviour or with mild/moderate problems, one with clear communication and interaction problems, and another with pronounced negative and demanding behaviour. Results More than 85% of infants with normal behaviour or mild problems at 14–15 months were reported to behave relatively typically as toddlers at 36–37 months. A similar percentage of infants with moderate communication problems outgrew their problems by the time they were toddlers. However, infants with severe problems had mild to severe problems as toddlers, and did not show completely normal behaviour. Improvement over time occurred more often in children with negative and demanding behaviour than in children with communication and interaction problems. The former showed less homotypic continuity than the latter. Conclusions Negative and demanding behaviour is more often transient and a less specific predictor of problems in toddlerhood than communication and interaction problems. PMID:25061477

  19. A cross-sectional analysis of women’s mental health problems: examining the association with different types of violence among a sample of Brazilian mothers

    PubMed Central

    2013-01-01

    Background Mental health problems are the major cause of disability in poor countries, and women are the individuals most affected. The World Health Organization points out that violence against women is the leading cause of mental health problems. This study seeks to identify explanatory factors for women’s mental health problems, highlighting situations of violence suffered by them during childhood, when living with a partner and in the community. Method A cross-sectional analysis was conducted with 389 mothers with schoolchildren in a city in the state of Rio de Janeiro (Brazil). Profile variables and childhood and adult life experiences were researched and organized in three analytical blocks. A binary logistic regression model was used, divided into hierarchical blocks. Results The final model shows that women who were the victims of severe physical violence by their partner were more likely (OR = 8.2) to suffer from mental health problems than those who had never been exposed to this type of violence. The mothers of children with behavior problems are more likely to have mental health problems (OR = 3.0) than mothers whose children do not manifest behavioral problems. Conclusion This study shows that women’s mental health problems are particularly related to the experience of physical violence, especially that occurring in intimate partner relationships. Based on this premise, this work recommends that multidimensional issues need to be included in women’s health assistance programs duly incorporating the specificity of victimization by violence. PMID:23587110

  20. Sex Differences in the Reciprocal Relationships between Mild and Severe Corporal Punishment and Children's Internalizing Problem Behavior in a Chinese Sample

    ERIC Educational Resources Information Center

    Xing, Xiaopei; Wang, Meifang

    2013-01-01

    The study aimed to investigate the sex differences in the reciprocal relations between parental corporal punishment and child internalizing problem behavior in China. Four hundred fifty-four Chinese elementary school-age children completed measures of their parental corporal punishment toward them and their own internalizing problem behavior at…

  1. Youth: Criminal Involvement and Problems of Resocialization.

    ERIC Educational Resources Information Center

    Lelekov, V. A.; Prokhorov, Iu. N.

    1995-01-01

    Reports on a survey of youth crime, youthful criminals, and efforts at resocialization in contemporary Russia. Asserts that political and social change have resulted in social stratification and criminal behavior. Maintains that the high level of recidivism is caused by a lack of coordinated efforts by public institutions. (CFR)

  2. Dual colour fluorescence in situ hybridization to paraffin-embedded samples to deduce the presence of the der(X)t(X;18)(p11.2;q11.2) and involvement of either the SSX1 or SSX2 gene: a diagnostic and prognostic aid for synovial sarcoma.

    PubMed

    Lu, Y J; Birdsall, S; Summersgill, B; Smedley, D; Osin, P; Fisher, C; Shipley, J

    1999-03-01

    Identification of the t(X;18)(p11.2;q11.2) and the fusion gene products, SYT-SSX1 and SYT-SSX2, associated with a high proportion of synovial sarcomas, has been shown to be a useful diagnostic aid. This study demonstrates the application of dual colour fluorescence in situ hybridization to paraffin-embedded samples to deduce the presence of the derivative X chromosome and also the position of the breakpoint on chromosome X at either the SSX1 or the SSX2 gene. This used region specific markers from chromosomes X and 18 and an optimized protocol involving microwave exposure. Novel and rapid scoring criteria were validated which circumvented potential problems of nuclear truncation and defining cell boundaries. This involved blind analysis of two negative sarcoma samples and three synovial sarcomas in which corresponding frozen material had been previously shown to have the translocation involving different SSX genes. Six new cases diagnosed as synovial sarcoma were also analysed; two monophasic and two biphasic case were deduced to have a breakpoint in the SSX1 gene, one monophasic case an SSX2 breakpoint, and one case did not show rearrangement of the region. The ability to analyse formalin-fixed, paraffin-embedded samples in this way has practical implications for aiding the diagnosis of difficult cases, recently ascribed prognostic relevance, and allows further retrospective studies to be carried out. The methodology is also applicable to the identification of other tumour specific translocations in paraffin-embedded material. PMID:10398111

  3. The program structure does not reliably recover the correct population structure when sampling is uneven: subsampling and new estimators alleviate the problem.

    PubMed

    Puechmaille, Sebastien J

    2016-05-01

    Inferences of population structure and more precisely the identification of genetically homogeneous groups of individuals are essential to the fields of ecology, evolutionary biology and conservation biology. Such population structure inferences are routinely investigated via the program structure implementing a Bayesian algorithm to identify groups of individuals at Hardy-Weinberg and linkage equilibrium. While the method is performing relatively well under various population models with even sampling between subpopulations, the robustness of the method to uneven sample size between subpopulations and/or hierarchical levels of population structure has not yet been tested despite being commonly encountered in empirical data sets. In this study, I used simulated and empirical microsatellite data sets to investigate the impact of uneven sample size between subpopulations and/or hierarchical levels of population structure on the detected population structure. The results demonstrated that uneven sampling often leads to wrong inferences on hierarchical structure and downward-biased estimates of the true number of subpopulations. Distinct subpopulations with reduced sampling tended to be merged together, while at the same time, individuals from extensively sampled subpopulations were generally split, despite belonging to the same panmictic population. Four new supervised methods to detect the number of clusters were developed and tested as part of this study and were found to outperform the existing methods using both evenly and unevenly sampled data sets. Additionally, a subsampling strategy aiming to reduce sampling unevenness between subpopulations is presented and tested. These results altogether demonstrate that when sampling evenness is accounted for, the detection of the correct population structure is greatly improved. PMID:26856252

  4. [The problem of determining asbestos in bulk materials: a study of the effect of grinding on the diffractometric response of the chrysotile content in an asbestos cement sample].

    PubMed

    Puledda, S; Paoletti, L

    1993-01-01

    To determine the asbestos content in a bulk sample by X-ray diffractometry, the sample must be previously comminuted until an adequate granulometry is reached. However, this treatment can produce a decrease in fibre crystallinity which, in turn, causes an attenuation of the diffractometric response of asbestos. The authors studied a "wet" comminution method that was tested on an asbestos-cement sample containing chrysotile. This procedure made it possible to limit the attenuation of the diffractometric response of chrysotile to reasonable values (about 20%). Moreover, the study of the comminution kinetics revealed a time interval during which both fibre granulometry and diffractometric response tend to reach a plateau value. In this interval, the comminution time is not a critical factor with respect to the diffractometric behaviour of chrysotile. Therefore, this interval offers favourable conditions for preparing bulk samples to be submitted to X-ray diffraction. PMID:8255261

  5. Sampling Development

    PubMed Central

    Adolph, Karen E.; Robinson, Scott R.

    2011-01-01

    Research in developmental psychology requires sampling at different time points. Accurate depictions of developmental change provide a foundation for further empirical studies and theories about developmental mechanisms. However, overreliance on widely spaced sampling intervals in cross-sectional and longitudinal designs threatens the validity of the enterprise. This article discusses how to sample development in order to accurately discern the shape of developmental change. The ideal solution is daunting: to summarize behavior over 24-hour intervals and collect daily samples over the critical periods of change. We discuss the magnitude of errors due to undersampling, and the risks associated with oversampling. When daily sampling is not feasible, we offer suggestions for sampling methods that can provide preliminary reference points and provisional sketches of the general shape of a developmental trajectory. Denser sampling then can be applied strategically during periods of enhanced variability, inflections in the rate of developmental change, or in relation to key events or processes that may affect the course of change. Despite the challenges of dense repeated sampling, researchers must take seriously the problem of sampling on a developmental time scale if we are to know the true shape of developmental change. PMID:22140355

  6. The Problems with Access to Compulsory Education in China and the Effects of the Policy of Direct Subsidies to Students: An Empirical Study Based on a Small Sample

    ERIC Educational Resources Information Center

    Yanqing, Ding

    2012-01-01

    After a brief review of the achievements and the problems in compulsory education enrollment in the thirty years since the reform and opening up, this study analyzes the current compulsory education enrollment and dropout rates in China's least-developed regions and the factors affecting school enrollment based on survey data from a small sample…

  7. A Quantitative Genetic Analysis of the Associations among Language Skills, Peer Interactions, and Behavioral Problems in Childhood: Results from a Sample of Twins

    ERIC Educational Resources Information Center

    Beaver, Kevin M.; Boutwell, Brian B.; Barnes, J. C.; Schwartz, Joseph A.; Connolly, Eric J.

    2014-01-01

    A body of empirical research has revealed that there are associations among language skills, peer interactions, and behavioral problems in childhood. At the same time, however, there has been comparatively less research devoted to exploring the mutual unfolding of these factors over the first few years of life. The current study is designed to…

  8. ADHD and Other Associated Developmental Problems in Children with Mild Mental Retardation. The Use of the "Five-To-Fifteen" Questionnaire in a Population-Based Sample

    ERIC Educational Resources Information Center

    Lindblad, Ida; Gillberg, Christopher; Fernell, Elisabeth

    2011-01-01

    The aim was to examine the rates and types of parent reported neuropsychiatric problems in children and adolescents with mild mental retardation (MMR) (mild intellectual disability/UK) using the Five-To-Fifteen questionnaire (FTF). The target group comprised all pupils with clinically diagnosed MMR, aged between 7 and 15 years, attending the…

  9. Problems with "n"th-Term Problems

    ERIC Educational Resources Information Center

    Matteson, Shirley M.

    2010-01-01

    An nth-term problem involves a sequence. Students must determine which expression will allow them to calculate the nth position of the sequence. To solve such problems, students are to find "a rule that determines the number of elements in a step from the step number." These types of problems help students develop concepts of functions, variables,…

  10. Screening for intellectual disability in persons with a substance abuse problem: Exploring the validity of the Hayes Ability Screening Index in a Dutch-speaking sample.

    PubMed

    To, Wing Ting; Vanheule, Stijn; Vanderplasschen, Wouter; Audenaert, Kurt; Vandevelde, Stijn

    2014-11-12

    There is an increasing interest in screening instruments to detect intellectual disability (ID) in a quick and accurate way in mental health services as well as in the criminal justice system in order to provide appropriate support for people with undetected needs caused by ID. An instrument that has been proven to be useful in both settings is the Hayes Ability Screening Index (HASI). This study assessed the validity of the Dutch version of the HASI in persons with a substance abuse problem residing in mental health services, whether or not mandated to treatment by court order. The HASI was conducted along with the Wechsler Adult Intelligence Scale III as the criterion for validity to 90 participants. Additionally, the influence of psychiatric disorder and medication use on the HASI result was examined. A significant positive relationship was found between the two instruments, demonstrating convergent validity. Using a Receiver Operating Characteristic (ROC) curve analysis, the discriminative ability of the HASI with a cut-off score of 85 was found to be adequate, yielding in a good balance between sensitivity and specificity. The HASI was not distorted by the presence of the substance abuse problem or other psychiatric illnesses and medication did not influence the HASI scores in this study. These findings indicate that the HASI provides a time-efficient and resource-conscious way to detect ID in persons with a substance problem, thus addressing a critical need in mental health settings. PMID:25462510

  11. Study the Problem.

    ERIC Educational Resources Information Center

    Choate, Joyce S.

    1990-01-01

    The initial step of a strategic process for solving mathematical problems, "studying the question," is discussed. A lesson plan for teaching students to identify and revise arithmetic problems is presented, involving directed instruction and supervised practice. (JDD)

  12. Parent Involvement.

    ERIC Educational Resources Information Center

    LaCrosse, Ed

    The paper discusses the rationale and guidelines for parent involvement in HCEEP (Handicapped Children's Early Education Program) projects. Ways of assessing parents' needs are reviewed, as are four types of services to meet the identified needs: parent education, direct participation, parent counseling, and parent provided programs. Materials and…

  13. Genetic and environmental etiology of the relationship between childhood hyperactivity/inattention and conduct problems in a South Korean twin sample.

    PubMed

    Hur, Yoon-Mi

    2015-06-01

    Recently, there has been increased research into the etiology of the comorbidity between hyperactivity/inattention problems (HIP) and conduct problems (CP). However, the nature of the etiology of the comorbidity has remained unclear. Mothers of 507 pairs of twins, comprised of 221 monozygotic (MZ) and 286 dizygotic (DZ) twin pairs aged from 6 to 13 years (mean = 9.6 years; SD = 2.0 years), completed the HIP and the CP scale of the Strengths and Difficulties Questionnaire (SDQ) via a telephone interview. The phenotypic correlation between HIP and CP was 0.43 (p < .01). MZ and DZ twin correlations were, respectively, 0.48 (95%CI: 0.37-0.58) and 0.06 (95% CI: -0.06-0.19) for HIP and 0.38 (95% CI: 0.26-0.49) and 0.35 (95% CI: 0.25-0.45) for CP. The bivariate model-fitting results revealed additive genetic correlation of 1.0 (95% CI: 0.72-1.00), a complete overlap of additive genetic variance component between HIP and CP, supporting the importance of correlated additive genetic risk factors for the comorbid condition of HIP and CP. HIP was additionally influenced by non-additive genetic factors that did not contribute to the relationship between HIP and CP. There was a significant but moderate child-specific environmental correlation (r e = 0.37) between HIP and CP. CP was additionally influenced by shared family environmental influences. While the results of the present study are generally consistent with the findings from Western twin studies of the relationship between HIP and CP, they add a new finding to the extant literature by showing that it is additive rather than non-additive genetic factors that are responsible for the co-occurrence of HIP and CP. PMID:25926162

  14. Non starch polysaccharide hydrolyzing enzymes as feed additives: detection of enzyme activities and problems encountered with quantitative determination in complex samples.

    PubMed

    Vahjen, W; Gläser, K; Froeck, M; Simon, O

    1997-01-01

    Chromogenic substrates, an agar diffusion assay and viscosity reduction were used to estimate beta-glucanase and xylanase activities in water soluble extracts of different feedstuffs and digesta supernatants. The dinitrosalicylic acid reducing sugar method was employed to calibrate results from different methods based on international units (IU, glucose equivalents). The detection of dye release from chromogenic substrates was a suitable method, allowing the detection of 0.05 IU of enzyme activity per ml of extract, although measurements in digesta supernatants were limited in linearity (0.1-0.5 IU/ml supernatant). With the agar diffusion assay the detection of enzyme activity was possible over a wider concentration range (extracts: 0.05-1 IU/ml, digesta supernatants: 0.1-1 IU/ml), but visual evaluation led to inaccurate measurement. Accuracy can be improved by computer based evaluation of digital images. The use of viscosity reduction produced linear standard curves from 0.01 to 0.5 IU/ml in feed extracts, but reliability of measurements depended on modification of substrates. Quantification of enzyme activities was influenced by matrix effects of complex samples. Cereal dependant differences were found in various extracts of feed mixtures and cereal extracts. Digesta supernatants partly inhibited enzyme activity, depending on the origin of the sample. Interaction of substrates with digesta components varied between methods. The sensitivity of the methods is comparable, however, all methods require specific calibrations to account for matrix- and enzyme specific effects. PMID:9345597

  15. Statistical distribution sampling

    NASA Technical Reports Server (NTRS)

    Johnson, E. S.

    1975-01-01

    Determining the distribution of statistics by sampling was investigated. Characteristic functions, the quadratic regression problem, and the differential equations for the characteristic functions are analyzed.

  16. Problems, possibilities and limitations of inductively coupled plasma atomic emission spectrometry in the determination of platinum, palladium and rhodium in samples with different matrix composition

    NASA Astrophysics Data System (ADS)

    Petrova, P.; Velichkov, S.; Velitchkova, N.; Havezov, I.; Daskalova, N.

    2010-02-01

    The economic and geological importance of platinum group of elements has led to the development of analytical methods to quantify them in different types of samples. In the present paper the quantitative information for spectral interference in radial viewing 40.68 MHz inductively coupled plasma atomic emission spectrometry in the determination of Pt, Pd and Rh in the presence of complex matrix, containing Al, Ca, Fe, Mg, Mn, P and Ti as matrix constituents was obtained. The database was used for optimum line selections. By using the selected analysis lines the following detection limits in ng g - 1 were obtained: Pt 1700, Pd-1440, Rh-900. The reached detection limits determine the possibilities and limitation of the direct ICP-AES method in the determination of Pt, Pd and Rh in geological and environmental materials. The database for spectral interferences in the presence of aluminum can be used for the determination of platinum group of elements in car catalysts. The accuracy of the analytical results was experimentally demonstrated by two certified reference materials that were analyzed: SARM 7, Pt ore and recycled auto-catalyst certified reference material SRM 2556.

  17. The Relations among Cumulative Risk, Parenting, and Behavior Problems during Early Childhood

    ERIC Educational Resources Information Center

    Trentacosta, Christopher J.; Hyde, Luke W.; Shaw, Daniel S.; Dishion, Thomas J.; Gardner, Frances; Wilson, Melvin

    2008-01-01

    Background: This study examined relations among cumulative risk, nurturant and involved parenting, and behavior problems across early childhood. Methods: Cumulative risk, parenting, and behavior problems were measured in a sample of low-income toddlers participating in a family-centered program to prevent conduct problems. Results: Path analysis…

  18. Superposition Enhanced Nested Sampling

    NASA Astrophysics Data System (ADS)

    Martiniani, Stefano; Stevenson, Jacob D.; Wales, David J.; Frenkel, Daan

    2014-07-01

    The theoretical analysis of many problems in physics, astronomy, and applied mathematics requires an efficient numerical exploration of multimodal parameter spaces that exhibit broken ergodicity. Monte Carlo methods are widely used to deal with these classes of problems, but such simulations suffer from a ubiquitous sampling problem: The probability of sampling a particular state is proportional to its entropic weight. Devising an algorithm capable of sampling efficiently the full phase space is a long-standing problem. Here, we report a new hybrid method for the exploration of multimodal parameter spaces exhibiting broken ergodicity. Superposition enhanced nested sampling combines the strengths of global optimization with the unbiased or athermal sampling of nested sampling, greatly enhancing its efficiency with no additional parameters. We report extensive tests of this new approach for atomic clusters that are known to have energy landscapes for which conventional sampling schemes suffer from broken ergodicity. We also introduce a novel parallelization algorithm for nested sampling.

  19. Sampling and Sample Preparation

    NASA Astrophysics Data System (ADS)

    Morawicki, Rubén O.

    Quality attributes in food products, raw materials, or ingredients are measurable characteristics that need monitoring to ensure that specifications are met. Some quality attributes can be measured online by using specially designed sensors and results obtained in real time (e.g., color of vegetable oil in an oil extraction plant). However, in most cases quality attributes are measured on small portions of material that are taken periodically from continuous processes or on a certain number of small portions taken from a lot. The small portions taken for analysis are referred to as samples, and the entire lot or the entire production for a certain period of time, in the case of continuous processes, is called a population. The process of taking samples from a population is called sampling. If the procedure is done correctly, the measurable characteristics obtained for the samples become a very accurate estimation of the population.

  20. Problem Periods

    MedlinePlus

    ... gov/ Home Body Getting your period Problem periods Problem periods It’s common to have cramps or feel ... doctor Some common period problems Signs of period problems top One way to know if you may ...

  1. Balance Problems

    MedlinePlus

    ... it could be a sign of a balance problem. Balance problems can make you feel unsteady or as if ... related injuries, such as hip fracture. Some balance problems are due to problems in the inner ear. ...

  2. Balance Problems

    MedlinePlus

    ... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady or as ... fall-related injuries, such as hip fracture. Some balance problems are due to problems in the inner ...

  3. A Comparative Study of Involvement and Motivation among Casino Gamblers

    PubMed Central

    Lee, Choong-Ki; Lee, BongKoo; Bernhard, Bo Jason

    2009-01-01

    Objective The purpose of this paper is to investigate three different types of gamblers (which we label "non-problem", "some problem", and "probable pathological gamblers") to determine differences in involvement and motivation, as well as differences in demographic and behavioral variables. Methods The analysis takes advantage of a unique opportunity to sample on-site at a major casino in South Korea, and the resulting purposive sample yielded 180 completed questionnaires in each of the three groups, for a total number of 540. Factor analysis, analysis of variance (ANOVA) and Duncan tests, and Chi-square tests are employed to analyze the data collected from the survey. Results Findings from ANOVA tests indicate that involvement factors of importance/self-expression, pleasure/interest, and centrality derived from the factor analysis were significantly different among these three types of gamblers. The "probable pathological" and "some problem" gamblers were found to have similar degrees of involvement, and higher degrees of involvement than the non-problem gamblers. The tests also reveal that motivational factors of escape, socialization, winning, and exploring scenery were significantly different among these three types of gamblers. When looking at motivations to visit the casino, "probable pathological" gamblers were more likely to seek winning, the "some problem" group appeared to be more likely to seek escape, and the "non-problem" gamblers indicate that their motivations to visit centered around explorations of scenery and culture in the surrounding casino area. Conclusion The tools for exploring motivations and involvements of gambling provide valuable and discerning information about the entire spectrum of gamblers. PMID:20046388

  4. Musculoskeletal involvement in sarcoidosis*, **

    PubMed Central

    Nessrine, Akasbi; Zahra, Abourazzak Fatima; Taoufik, Harzy

    2014-01-01

    Sarcoidosis is a multisystem inflammatory disorder of unknown cause. It most commonly affects the pulmonary system but can also affect the musculoskeletal system, albeit less frequently. In patients with sarcoidosis, rheumatic involvement is polymorphic. It can be the presenting symptom of the disease or can appear during its progression. Articular involvement is dominated by nonspecific arthralgia, polyarthritis, and Löfgren's syndrome, which is defined as the presence of lung adenopathy, arthralgia (or arthritis), and erythema nodosum. Skeletal manifestations, especially dactylitis, appear mainly as complications of chronic, multiorgan sarcoidosis. Muscle involvement in sarcoidosis is rare and usually asymptomatic. The diagnosis of rheumatic sarcoidosis is based on X-ray findings and magnetic resonance imaging findings, although the definitive diagnosis is made by anatomopathological study of biopsy samples. Musculoskeletal involvement in sarcoidosis is generally relieved with nonsteroidal anti-inflammatory drugs or corticosteroids. In corticosteroid-resistant or -dependent forms of the disease, immunosuppressive therapy, such as treatment with methotrexate or anti-TNF-α, is employed. The aim of this review was to present an overview of the various types of osteoarticular and muscle involvement in sarcoidosis, focusing on their diagnosis and management. PMID:24831403

  5. Reciprocal longitudinal relations between nonresident father involvement and adolescent delinquency.

    PubMed

    Coley, Rebekah Levine; Medeiros, Bethany L

    2007-01-01

    Using a representative sample of low-income, primarily minority adolescents (N=647, aged 10-14 years at Wave 1), this study examined bidirectional longitudinal relations between nonresident father involvement, defined as contact and responsibility for children's care and behavior, and adolescent engagement in delinquent activities. Autoregressive and fixed effects models found that higher nonresident father involvement predicted subsequent decreases in adolescent delinquency, particularly for youth with initial engagement in delinquent activities. Adolescent delinquency did not predict subsequent changes in father involvement. However, the two factors covaried: As adolescent delinquency increased, so too did father involvement, suggesting that nonresident fathers may increase their involvement in the face of adolescent problem behavior, with this pattern driven primarily by African American families. PMID:17328697

  6. Promoting vital involvement.

    PubMed

    Kivnick, Helen Q; Stoffel, Sharon A

    2002-09-01

    Health care for the elderly generally focuses on health problems. This approach ignores the strengths and resources that maximize a person's autonomy, integrity, and ability to make contributions to society; and it exacerbates poor health. Vital involvement practice (VIP) is an approach to caring for the elderly that emphasizes an individual's capabilities by exploring factors both internal and external to the individual. VIP is identified as a model for health care providers that will improve the health and quality of life of elderly patients. PMID:12387120

  7. What Is Problem Solving?

    ERIC Educational Resources Information Center

    Martinez, Michael E.

    1998-01-01

    Many important human activities involve accomplishing goals without a script. There is no formula for true problem-solving. Heuristic, cognitive "rules of thumb" are the problem-solver's best guide. Learners should understand heuristic tools such as means-end analysis, working backwards, successive approximation, and external representation. Since…

  8. Problems of Advocacy.

    ERIC Educational Resources Information Center

    Ross, Robert

    This paper focusses on problems involved in adopting the newer modes of social science and professionalism. The complexities which precede these problems are recognized. It is mentioned that many recent entrants to these fields have made value commitments in their professionalism without very long detention at the portals of objectivity or…

  9. Problem Solving and Intelligence.

    ERIC Educational Resources Information Center

    Resnick, Lauren B.; Glaser, Robert

    This paper argues that a major aspect of intelligence is the ability to solve problems and that careful analysis of problem-solving behavior is a means of specifying many of the psychological processes that make up intelligence. The focus is on the mechanisms involved when, in the absence of complete instruction, a person must "invent" a new…

  10. California's Water Problems.

    ERIC Educational Resources Information Center

    Wheatley, Judy; Sudman, Rita Schmidt, Ed.

    This packet of instructional materials is designed to give social science students in grades 6-9 a first-hand experience in working out solutions to real-life problems involving the management of California's water. Students work in groups on one of three problems presented in the packet: (1) the management of the Sacramento-San Joaquin Delta that…

  11. Childbirth Problems

    MedlinePlus

    ... labor starts before 37 completed weeks of pregnancy Problems with the umbilical cord Problems with the position of the baby, such as ... feet first Birth injuries For some of these problems, the baby may need to be delivered surgically ...

  12. Balance Problems

    MedlinePlus

    ... version of this page please turn Javascript on. Balance Problems About Balance Problems Have you ever felt dizzy, lightheaded, or ... dizziness problem during the past year. Why Good Balance is Important Having good balance means being able ...

  13. Energy Problems and Environmental Concern

    ERIC Educational Resources Information Center

    Train, Russell E.

    1973-01-01

    Discusses problems encountered in energy extraction and consumption, involving nuclear power plant construction, environmental consequences of energy systems, and energy conservation ethics. Indicates that the increasing concern over environmental quality is not the true cause of present energy problems. (CC)

  14. Chorionic villus sampling

    MedlinePlus

    Chorionic villus sampling (CVS) is a test some pregnant women have to screen their baby for genetic problems. ... CVS can be done through the cervix (transcervical) or through the belly (transabdominal). Miscarriage rates are slightly ...

  15. Fibonacci's Triangle: A Vehicle for Problem Solving.

    ERIC Educational Resources Information Center

    Ouellette, Hugh

    1979-01-01

    A method for solving certain types of problems is illustrated by problems related to Fibonacci's triangle. The method involves pattern recognition, generalizing, algebraic manipulation, and mathematical induction. (MP)

  16. Adolescent Temperament: Childhood Problem Precursors and Problem Behavior Correlates.

    ERIC Educational Resources Information Center

    Windle, Michael

    Interrelations between childhood behavior problems and adolescent temperament, and between adolescent temperament and problem behaviors, were studied. A sample of 311 adolescents with an average age of 15.7 years completed self-report measures regarding behavior problems before age 13, temperament, alcohol consumption, alcohol-related problems,…

  17. Execution of Multidisciplinary Design Optimization Approaches on Common Test Problems

    NASA Technical Reports Server (NTRS)

    Balling, R. J.; Wilkinson, C. A.

    1997-01-01

    A class of synthetic problems for testing multidisciplinary design optimization (MDO) approaches is presented. These test problems are easy to reproduce because all functions are given as closed-form mathematical expressions. They are constructed in such a way that the optimal value of all variables and the objective is unity. The test problems involve three disciplines and allow the user to specify the number of design variables, state variables, coupling functions, design constraints, controlling design constraints, and the strength of coupling. Several MDO approaches were executed on two sample synthetic test problems. These approaches included single-level optimization approaches, collaborative optimization approaches, and concurrent subspace optimization approaches. Execution results are presented, and the robustness and efficiency of these approaches an evaluated for these sample problems.

  18. Validation and use of a fast sample preparation method and liquid chromatography-tandem mass spectrometry in analysis of ultra-trace levels of 98 organophosphorus pesticide and carbamate residues in a total diet study involving diversified food types.

    PubMed

    Chung, Stephen W C; Chan, Benny T P

    2010-07-16

    This paper reports a comprehensive sensitive multi-residue liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for detection, identification and quantitation of 73 pesticides and their related products, a total of 98 analytes, belonging to organophosphorus pesticides (OPPs) and carbamates, in foods. The proposed method makes use of a modified QuEChERS (quick, easy, cheap, effective, rigged, and safe) procedure that combines isolation of the pesticides and sample clean-up in a single step. Analysis is performed by liquid chromatography-electrospray ionization-tandem mass spectrometry operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. Two main fragment ions for each pesticide were obtained to achieve the identification according to the SANCO guidelines 10684/2009. The method was validated with various food samples, including edible oil, meat, egg, cheese, chocolate, coffee, rice, tree nuts, citric fruits, vegetables, etc. No significant matrix effect was observed for tested pesticides, therefore, matrix-matched calibration was not necessary. Calibration curves were linear and covered from 1 to 20 microg L(-1) for all compounds studied. The average recoveries, measured at 10 microg kg(-1), were in the range 70-120% for all of the compounds tested with relative standard deviations below 20%, while a value of 10 microg kg(-1) has been established as the method limit of quantitation (MLOQ) for all target analytes. Similar trueness and precision results were also obtained for spiking at 200 microg kg(-1). Expanded uncertainty values were in the range 21-27% while the HorRat ratios were below 1. The method has been successfully applied to the analysis of 700 food samples in the course of a baseline monitoring study of OPPs and carbamates. PMID:20557892

  19. National Sample Assessment Protocols

    ERIC Educational Resources Information Center

    Ministerial Council on Education, Employment, Training and Youth Affairs (NJ1), 2012

    2012-01-01

    These protocols represent a working guide for planning and implementing national sample assessments in connection with the national Key Performance Measures (KPMs). The protocols are intended for agencies involved in planning or conducting national sample assessments and personnel responsible for administering associated tenders or contracts,…

  20. Problem Solving through Paper Folding

    ERIC Educational Resources Information Center

    Wares, Arsalan

    2014-01-01

    The purpose of this article is to describe a couple of challenging mathematical problems that involve paper folding. These problem-solving tasks can be used to foster geometric and algebraic thinking among students. The context of paper folding makes some of the abstract mathematical ideas involved relatively concrete. When implemented…

  1. Walking Problems

    MedlinePlus

    ... daily activities, get around, and exercise. Having a problem with walking can make daily life more difficult. ... walk is called your gait. A variety of problems can cause an abnormal gait and lead to ...

  2. Breathing Problems

    MedlinePlus

    ... re not getting enough air. Sometimes mild breathing problems are from a stuffy nose or hard exercise. ... emphysema or pneumonia cause breathing difficulties. So can problems with your trachea or bronchi, which are part ...

  3. Erection problems

    MedlinePlus

    ... cord injury In some cases, your emotions or relationship problems can lead to ED, such as: Poor ... you stressed, depressed, or anxious? Are you having relationship problems? You may have a number of different ...

  4. Joint Problems

    MedlinePlus

    ... ankles and toes. Other types of arthritis include gout or pseudogout. Sometimes, there is a mechanical problem ... for more information on osteoarthritis, rheumatoid arthritis and gout. How Common are Joint Problems? Osteoarthritis, which affects ...

  5. Organized Activity Involvement among Rural Youth: Gender Differences in Associations between Activity Type and Developmental Outcomes

    ERIC Educational Resources Information Center

    Ferris, Kaitlyn A.; Oosterhoff, Benjamin; Metzger, Aaron

    2013-01-01

    The current study examined associations between organized activity involvement, academic achievement, and problem behavior in a sample of youth from a non-agricultural based rural community (M[subscript age] = 15.26, Age range = 11-19 years, N = 456). Analyses examined whether associations varied as a function of adolescent gender and age.…

  6. Data augmentation for models based on rejection sampling

    PubMed Central

    Rao, Vinayak; Lin, Lizhen; Dunson, David B.

    2016-01-01

    We present a data augmentation scheme to perform Markov chain Monte Carlo inference for models where data generation involves a rejection sampling algorithm. Our idea is a simple scheme to instantiate the rejected proposals preceding each data point. The resulting joint probability over observed and rejected variables can be much simpler than the marginal distribution over the observed variables, which often involves intractable integrals. We consider three problems: modelling flow-cytometry measurements subject to truncation; the Bayesian analysis of the matrix Langevin distribution on the Stiefel manifold; and Bayesian inference for a nonparametric Gaussian process density model. The latter two are instances of doubly-intractable Markov chain Monte Carlo problems, where evaluating the likelihood is intractable. Our experiments demonstrate superior performance over state-of-the-art sampling algorithms for such problems. PMID:27279660

  7. Factors Associated with Time to Identify Physical Problems of Nursing Home Residents with Dementia

    PubMed Central

    Kovach, Christine R.; Logan, Brent R.; Simpson, Michelle R.; Reynolds, Sheila

    2010-01-01

    This study describes new problems emerging over six weeks for nursing home residents with advanced dementia and factors associated with time to identify the problems. The sample of 65 developed 149 new acute problems or exacerbations of existing conditions over the six weeks of data collection. The majority of these problems involved uncontrolled pain, new infections and severe psychoses. Nurse assessment skill was associated with a shorter time to identify the new problem and more time spent on the problem. A higher ratio of new to existing interventions was also associated with a shorter time to identify the problem. Other patient characteristics associated with time to identify problems included non-specific vocalizations, physical signs, cognitive status and length of stay. While future research is warranted, findings from this study highlight the frequency of problems requiring treatment and suggest that improved assessment of residents may decrease the time to identify new problems. PMID:20237337

  8. Approaches to the sign problem in lattice field theory

    NASA Astrophysics Data System (ADS)

    Gattringer, Christof; Langfeld, Kurt

    2016-08-01

    Quantum field theories (QFTs) at finite densities of matter generically involve complex actions. Standard Monte Carlo simulations based upon importance sampling, which have been producing quantitative first principle results in particle physics for almost forty years, cannot be applied in this case. Various strategies to overcome this so-called sign problem or complex action problem were proposed during the last thirty years. We here review the sign problem in lattice field theories, focusing on two more recent methods: dualization to worldline type of representations and the density-of-states approach.

  9. Sampling diffusive transition paths

    SciTech Connect

    F. Miller III, Thomas; Predescu, Cristian

    2006-10-12

    We address the problem of sampling double-ended diffusive paths. The ensemble of paths is expressed using a symmetric version of the Onsager-Machlup formula, which only requires evaluation of the force field and which, upon direct time discretization, gives rise to a symmetric integrator that is accurate to second order. Efficiently sampling this ensemble requires avoiding the well-known stiffness problem associated with sampling infinitesimal Brownian increments of the path, as well as a different type of stiffness associated with sampling the coarse features of long paths. The fine-features sampling stiffness is eliminated with the use of the fast sampling algorithm (FSA), and the coarse-feature sampling stiffness is avoided by introducing the sliding and sampling (S&S) algorithm. A key feature of the S&S algorithm is that it enables massively parallel computers to sample diffusive trajectories that are long in time. We use the algorithm to sample the transition path ensemble for the structural interconversion of the 38-atom Lennard-Jones cluster at low temperature.

  10. Sampling diffusive transition paths.

    PubMed

    Miller, Thomas F; Predescu, Cristian

    2007-04-14

    The authors address the problem of sampling double-ended diffusive paths. The ensemble of paths is expressed using a symmetric version of the Onsager-Machlup formula, which only requires evaluation of the force field and which, upon direct time discretization, gives rise to a symmetric integrator that is accurate to second order. Efficiently sampling this ensemble requires avoiding the well-known stiffness problem associated with the sampling of infinitesimal Brownian increments of the path, as well as a different type of stiffness associated with the sampling of the coarse features of long paths. The fine-feature sampling stiffness is eliminated with the use of the fast sampling algorithm, and the coarse-feature sampling stiffness is avoided by introducing the sliding and sampling (S&S) algorithm. A key feature of the S&S algorithm is that it enables massively parallel computers to sample diffusive trajectories that are long in time. The authors use the algorithm to sample the transition path ensemble for the structural interconversion of the 38-atom Lennard-Jones cluster at low temperature. PMID:17444696

  11. Capillary sample

    MedlinePlus

    ... using capillary blood sampling. Disadvantages to capillary blood sampling include: Only a limited amount of blood can be drawn using this method. The procedure has some risks (see below). Capillary ...

  12. Parent Predictors of Changes in Child Behavior Problems.

    PubMed

    Tichovolsky, Marianne H; Arnold, David H; Baker, Courtney N

    2013-11-01

    The present study examined whether ineffective discipline, single parent status, social support, parent involvement, and parent depression predicted changes in preschoolers' (N = 129) behavior problems. This study also evaluated whether child sex and ethnicity moderated the relationships between these variables and changes in problem behavior. Parents completed questionnaires at the beginning of the study, and parent, teacher, and observational ratings of children's behavior problems were collected twice during the school year. Parents' own social support predicted improvement for boys and parent depression was associated with worsening symptoms for girls. Single parenthood and parent involvement predicted changes in behavior problems for the sample as a whole. Several significant ethnic differences emerged, highlighting the importance of considering cultural context in studies of parenting and child externalizing behavior. PMID:24347757

  13. Parent Predictors of Changes in Child Behavior Problems

    PubMed Central

    Tichovolsky, Marianne H.; Arnold, David H.; Baker, Courtney N.

    2013-01-01

    The present study examined whether ineffective discipline, single parent status, social support, parent involvement, and parent depression predicted changes in preschoolers’ (N = 129) behavior problems. This study also evaluated whether child sex and ethnicity moderated the relationships between these variables and changes in problem behavior. Parents completed questionnaires at the beginning of the study, and parent, teacher, and observational ratings of children’s behavior problems were collected twice during the school year. Parents’ own social support predicted improvement for boys and parent depression was associated with worsening symptoms for girls. Single parenthood and parent involvement predicted changes in behavior problems for the sample as a whole. Several significant ethnic differences emerged, highlighting the importance of considering cultural context in studies of parenting and child externalizing behavior. PMID:24347757

  14. Astronauts' menu problem.

    NASA Technical Reports Server (NTRS)

    Lesso, W. G.; Kenyon, E.

    1972-01-01

    Consideration of the problems involved in choosing appropriate menus for astronauts carrying out SKYLAB missions lasting up to eight weeks. The problem of planning balanced menus on the basis of prepackaged food items within limitations on the intake of calories, protein, and certain elements is noted, as well as a number of other restrictions of both physical and arbitrary nature. The tailoring of a set of menus for each astronaut on the basis of subjective rankings of each food by the astronaut in terms of a 'measure of pleasure' is described, and a computer solution to this problem by means of a mixed integer programming code is presented.

  15. Balance Problems

    MedlinePlus

    ... our e-newsletter! Aging & Health A to Z Balance Problems Basic Facts & Information What are Balance Problems? Having good balance means being able to ... Only then can you “keep your balance.” Why Balance is Important Your feelings of dizziness may last ...

  16. Parking Problem

    ERIC Educational Resources Information Center

    Foster, Colin

    2012-01-01

    This is the story of a real problem, not a problem that is contrived, or invented for the convenience of the appropriate planning tool. This activity by a group of students, defined simply as "8FN", might be likened to an "end of term concert". If you just happened to be a delegate at the ATM Conference 2003 you might remember the analogy. Social…

  17. Chemical Reaction Problem Solving.

    ERIC Educational Resources Information Center

    Veal, William

    1999-01-01

    Discusses the role of chemical-equation problem solving in helping students predict reaction products. Methods for helping students learn this process must be taught to students and future teachers by using pedagogical skills within the content of chemistry. Emphasizes that solving chemical reactions should involve creative cognition where…

  18. Children Solve Problems.

    ERIC Educational Resources Information Center

    De Bono, Edward

    A group of children were presented with several tasks, including the invention of a sleep machine and a machine to weigh elephants. The tasks were chosen to involve the children in coping with problems of a distinct character. A study of the children's drawings and interpretations shows that children's thinking ability is not very different from…

  19. Circumference and Problem Solving.

    ERIC Educational Resources Information Center

    Blackburn, Katie; White, David

    The concept of pi is one of great importance to all developed civilization and one that can be explored and mastered by elementary students through an inductive and problem-solving approach. Such an approach is outlined and discussed. The approach involves the following biblical quotation: "And he made a moltin sea ten cubits from one brim to the…

  20. Sample Handling in Extreme Environments

    NASA Technical Reports Server (NTRS)

    Avellar, Louisa; Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph

    2013-01-01

    Harsh environments, such as that on Venus, preclude the use of existing equipment for functions that involve interaction with the environment. The operating limitations of current high temperature electronics are well below the actual temperature and pressure found on Venus (460 deg C and 92 atm), so proposed lander configurations typically include a pressure vessel where the science instruments are kept at Earth-like temperature and pressure (25 deg C and 1 atm). The purpose of this project was to develop and demonstrate a method for sample transfer from an external drill to internal science instruments for a lander on Venus. The initial concepts were string and pneumatically driven systems; and the latter system was selected for its ability to deliver samples at very high speed. The pneumatic system was conceived to be driven by the pressure difference between the Venusian atmosphere and the inside of the lander. The pneumatic transfer of a small capsule was demonstrated, and velocity data was collected from the lab experiment. The sample transfer system was modeled using CAD software and prototyped using 3D printing. General structural and thermal analyses were performed to approximate the proposed system's mass and effects on the temperature and pressure inside of the lander. Additionally, a sampler breadboard for use on Titan was tested and functionality problems were resolved.

  1. Problems on Divisibility of Binomial Coefficients

    ERIC Educational Resources Information Center

    Osler, Thomas J.; Smoak, James

    2004-01-01

    Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…

  2. Predicting the Problem Behavior in Adolescents

    ERIC Educational Resources Information Center

    Karaman, Neslihan G.

    2013-01-01

    Problem statement: Problem behavior theory describes both protective factors and risk factors to explain adolescent problem behaviors, such as delinquency, alcohol use, and reckless driving. The theory holds that problem behaviors involving risky behavior are used by adolescents as a means to gain peer acceptance and respect. Problem behaviors…

  3. The Relationship between Post-Traumatic Stress Symptoms and Substance Use among Adolescents Involved with Child Welfare: Implications for Emerging Adulthood

    ERIC Educational Resources Information Center

    Goldstein, Abby L.; Wekerle, Christine; Tonmyr, Lil; Thornton, Tiffany; Waechter, Randall; Pereira, Jessica; Chung, Ronald

    2011-01-01

    The purpose of the present study was to examine the role of posttraumatic stress symptoms (PTSS) in predicting substance use and substance-related problems in a sample of older youth and emerging adults involved with child welfare. The sample was drawn from the Maltreatment and Adolescent Pathways (MAP) longitudinal study (Wekerle et al. 2009).…

  4. Sampling Development

    ERIC Educational Resources Information Center

    Adolph, Karen E.; Robinson, Scott R.

    2011-01-01

    Research in developmental psychology requires sampling at different time points. Accurate depictions of developmental change provide a foundation for further empirical studies and theories about developmental mechanisms. However, overreliance on widely spaced sampling intervals in cross-sectional and longitudinal designs threatens the validity of…

  5. 32 CFR 651.36 - Public involvement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... collaborative issue identification and problem solving. Such involvement demonstrates that the Army is committed... considering the extent practicable of public interaction (40 CFR 1501.4(b)), factors to be weighed include:...

  6. 32 CFR 651.36 - Public involvement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... collaborative issue identification and problem solving. Such involvement demonstrates that the Army is committed... considering the extent practicable of public interaction (40 CFR 1501.4(b)), factors to be weighed include:...

  7. 32 CFR 651.36 - Public involvement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... collaborative issue identification and problem solving. Such involvement demonstrates that the Army is committed... considering the extent practicable of public interaction (40 CFR 1501.4(b)), factors to be weighed include:...

  8. 32 CFR 651.36 - Public involvement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... collaborative issue identification and problem solving. Such involvement demonstrates that the Army is committed... considering the extent practicable of public interaction (40 CFR 1501.4(b)), factors to be weighed include:...

  9. Urination Problems

    MedlinePlus

    ... back or groin? Yes You may have a KIDNEY STONE or another serious problem. EMERGENCY See your doctor ... the bladder, called INTERSTITIAL CYSTITIS, or from a KIDNEY STONE stuck in the bladder, or a chemical in ...

  10. Kidney Problems

    MedlinePlus

    ... our e-newsletter! Aging & Health A to Z Kidney Problems Basic Facts & Information The kidneys are two ... the production of red blood cells. What are Kidney Diseases? For about one-third of older people, ...

  11. Hearing Problems

    MedlinePlus

    ... This flow chart will help direct you if hearing loss is a problem for you or a family ... may damage the inner ear. This kind of hearing loss is called OCCUPATIONAL. Prevent occupational hearing loss by ...

  12. Sleep Problems

    MedlinePlus

    ... For Consumers Consumer Information by Audience For Women Sleep Problems Share Tweet Linkedin Pin it More sharing ... PDF 474KB) En Español Medicines to Help You Sleep Tips for Better Sleep Basic Facts about Sleep ...

  13. Thyroid Problems

    MedlinePlus

    ... treated differently. Common thyroid disorders and problems include: Hypothyroidism Hypothyroidism is a disorder in which your thyroid doesn’ ... normal after you get better. If you have hypothyroidism, however, the levels of T4 in your blood ...

  14. Nipple problems

    MedlinePlus

    ... Inverted nipple; Nipple problems Images Female breast Intraductal papilloma Mammary gland Abnormal discharge from the nipple Normal ... 8. Read More Breast cancer Endocrine glands Intraductal papilloma Update Date 11/16/2014 Updated by: Cynthia ...

  15. Vision problems

    MedlinePlus

    ... which nothing can be seen) Vision loss and blindness are the most severe vision problems. Causes Vision ... that look faded. The most common cause of blindness in people over age 60. Eye infection, inflammation, ...

  16. Swallowing problems

    MedlinePlus

    ... the home Dry mouth during cancer treatment Enteral nutrition - child - managing problems Gastrostomy feeding tube - bolus Jejunostomy feeding tube Mouth and neck radiation - discharge Multiple sclerosis - discharge Stroke - discharge Update Date 5/15/2014 ...

  17. Speech Problems

    MedlinePlus

    ... a person's ability to speak clearly. Some Common Speech Disorders Stuttering is a problem that interferes with fluent ... is a language disorder, while stuttering is a speech disorder. A person who stutters has trouble getting out ...

  18. Telescope loading: A problem reduction approach

    NASA Technical Reports Server (NTRS)

    Bresina, John L.

    1994-01-01

    This paper presents a problem reduction approach to telescope loading. To study time-varying celestial behavior, astronomers submit periodic observation campaigns which involve a sequence of observations at a given sampling frequency over months or years. The loader's task is to generate an assignment of observation tasks to each night in the time window such that resource demand does not exceed resource capacity and such that the observations usefully contribute to the campaigns' scientific purposes, in a manner that is fair to all participating astronomers.

  19. Eyelid Problems

    MedlinePlus

    ... wine stain, because of its resemblance to a dark red wine. If this birthmark involves the eye, ... examined by an ophthalmologist shortly after birth. Small dark moles, called nevi, on the eyelids or on ...

  20. Elevating sampling

    PubMed Central

    Labuz, Joseph M.; Takayama, Shuichi

    2014-01-01

    Sampling – the process of collecting, preparing, and introducing an appropriate volume element (voxel) into a system – is often under appreciated and pushed behind the scenes in lab-on-a-chip research. What often stands in the way between proof-of-principle demonstrations of potentially exciting technology and its broader dissemination and actual use, however, is the effectiveness of sample collection and preparation. The power of micro- and nanofluidics to improve reactions, sensing, separation, and cell culture cannot be accessed if sampling is not equally efficient and reliable. This perspective will highlight recent successes as well as assess current challenges and opportunities in this area. PMID:24781100

  1. Nonlinear problems in flight dynamics involving aerodynamic bifurcations

    NASA Technical Reports Server (NTRS)

    Tobak, M.; Chapman, G. T.

    1985-01-01

    Aerodynamic bifurcation is defined as the replacement of an unstable equilibrium flow by a new stable equilibrium flow at a critical value of a parameter. A mathematical model of the aerodynamic contribution to the aircraft's equations of motion is amended to accommodate aerodynamic bifurcations. Important bifurcations such as, the onset of large-scale vortex-shedding are defined. The amended mathematical model is capable of incorporating various forms of aerodynamic responses, including those associated with dynamic stall of airfoils.

  2. PROBLEMS INVOLVED IN COOPERATION BETWEEN UNIVERSITIES AND GOVERNMENT AGENCIES.

    ERIC Educational Resources Information Center

    SHIRLEY, JOHN W.

    THE UNRESOLVED PURPOSE OF EDUCATION IN A DEMOCRATIC SOCIETY--WHETHER ACADEMIC OR PRAGMATIC GOALS SHOULD PREVAIL--IS IDENTIFIED AS THE BASIC CAUSE OF THE CONFLICT BETWEEN THE FEDERAL GOVERNMENT AND INSTITUTIONS OF HIGHER EDUCATION. SINCE WORLD WAR II, FEDERAL SUPPORT HAS BEEN INCREASINGLY DIRECTED TOWARD ACTION PROGRAMS, INCLUDING SPECIAL…

  3. A nonhomogeneous elliptic problem involving critical growth in dimension two

    NASA Astrophysics Data System (ADS)

    Do Ó, João Marcos; Medeiros, Everaldo; Severo, Uberlandio

    2008-09-01

    In this paper we study a class of nonhomogeneous Schrödinger equations-[Delta]u+V(x)u=f(u)+h(x) in the whole two-dimension space where V(x) is a continuous positive potential bounded away from zero and which can be "large" at the infinity. The main difficulty in this paper is the lack of compactness due to the unboundedness of the domain besides the fact that the nonlinear term f(s) is allowed to enjoy the critical exponential growth by means of the Trudinger-Moser inequality. By combining variational arguments and a version of the Trudinger-Moser inequality, we establish the existence of two distinct solutions when h is suitably small.

  4. The problem of pain.

    PubMed

    Nicholson, Keith; Martelli, Michael F

    2004-01-01

    Pain problems, especially posttraumatic headache, are very common following head trauma. Pain may be the most significant problem, more disabling than any brain or other injuries, and interfering with aspects of cognition or other function. However, posttraumatic headache and most other chronic posttraumatic pain problems remain poorly understood. This article reviews fundamental issues that should be considered in understanding the nature of chronic pain including the distinction between acute and chronic pain; neurobiological distinctions between the lateral and medial pain system; nociceptive versus neuropathic or other central pain; sensitization effects; the widely accepted view of chronic pain as a multidimensional subjective experience involving sensory, motivational-affective and cognitive-behavioral components; the problem of mind-body dualism; the role of psychosocial factors in the onset, maintenance, exacerbation or severity of pain; plus issues of response bias and malingering. PMID:14732827

  5. Wireline fluid sampling

    SciTech Connect

    Michaels, J.; Moody, M.; Shwe, T.

    1995-12-31

    Accurate PVT data are crucial to well completion and production, formation evaluation and reservoir characterization. This is especially true for initial reservoir characterization where the PVF sample needs to be obtained prior to production. It is essential that the fluid sample be recovered as closely as possible to in-situ conditions whether by drill stem or wireline formation for. The need to remove drilling mud filtrate prior to collecting a sample has been widely recognized. Wireline testers which can pump fluid from a formation until filtrate is reduced to a minimum overcome this problem. While reducing sample contamination has been addressed, little emphasis has been placed on the need to control inlet pressure during filtrate removal or during sampling. Reducing contamination is important; however, there is equal need to determine the critical sampling pressure. The purpose is to prevent phase separation in the formation by regulating the sampling process based on this information and thereby obtain a more representative reservoir fluid sample. A recently introduced wireline instrument provides the capability of measuring the critical pressure prior to sampling, of controlling the sample pressure and of increasing the pressure in the sample container to compensate for temperature decline during delivery of that sample to a testing laboratory. Example of pressure tests while pumping and during pressure buildup are presented along with indicated sample properties. Introduction Wireline Formation Testers (WFT) provide an cost effective means to determine pressure as a function of depth and to recover samples of fluid from formations at selected depths. No other method can provide this type of information. Pressure data are used to estimate mobility, fluid contact and fluid density.

  6. SAMPLING SYSTEM

    DOEpatents

    Hannaford, B.A.; Rosenberg, R.; Segaser, C.L.; Terry, C.L.

    1961-01-17

    An apparatus is given for the batch sampling of radioactive liquids such as slurries from a system by remote control, while providing shielding for protection of operating personnel from the harmful effects of radiation.

  7. Problem-Framing: A perspective on environmental problem-solving

    NASA Astrophysics Data System (ADS)

    Bardwell, Lisa V.

    1991-09-01

    The specter of environmental calamity calls for the best efforts of an involved public. Ironically, the way people understand the issues all too often serves to discourage and frustrate rather than motivate them to action. This article draws from problem-solving perspectives offered by cognitive psychology and conflict management to examine a framework for thinking about environmental problems that promises to help rather than hinder efforts to address them. Problem-framing emphasizes focusing on the problem definition. Since how one defines a problem determines one's understanding of and approach to that problem, being able to redefine or reframe a problem and to explore the “problem space” can help broaden the range of alternatives and solutions examined. Problem-framing incorporates a cognitive perspective on how people respond to information. It explains why an emphasis on problem definition is not part of people's typical approach to problems. It recognizes the importance of structure and of having ways to organize that information on one's problem-solving effort. Finally, problem-framing draws on both cognitive psychology and conflict management for strategies to manage information and to create a problem-solving environment that not only encourages participation but can yield better approaches to our environmental problems.

  8. Fluidic sampling

    SciTech Connect

    Houck, E.D.

    1992-04-20

    This paper covers the development of the fluidic sampler and its testing in a fluidic transfer system. The major findings of this paper are as follows. Fluidic jet samples can dependably produce unbiased samples of acceptable volume. The fluidic transfer system with a fluidic sampler in-line will transfer water to a net lift of 37.2--39.9 feet at an average ratio of 0.02--0.05 gpm (77--192 cc/min). The fluidic sample system circulation rate compares very favorably with the normal 0.016--0.026 gpm (60--100 cc/min) circulation rate that is commonly produced for this lift and solution with the jet-assisted airlift sample system that is normally used at ICPP. The volume of the sample taken with a fluidic sampler is dependant on the motive pressure to the fluidic sampler, the sample bottle size and on the fluidic sampler jet characteristics. The fluidic sampler should be supplied with fluid having the motive pressure of the 140--150 percent of the peak vacuum producing motive pressure for the jet in the sampler. Fluidic transfer systems should be operated by emptying a full pumping chamber to nearly empty or empty during the pumping cycle, this maximizes the solution transfer rate.

  9. Fluidic sampling

    NASA Astrophysics Data System (ADS)

    Houck, E. D.

    1992-04-01

    This paper covers the development of the fluidic sampler and its testing in a fluidic transfer system. The major findings of this paper are as follows. Fluidic jet samples can dependably produce unbiased samples of acceptable volume. The fluidic transfer system with a fluidic sampler in-line will transfer water to a net lift of 37.2-39.9 feet at an average ratio of 0.02-0.05 gpm (77-192 cc/min). The fluidic sample system circulation rate compares very favorably with the normal 0.016-0.026 gpm (60-100 cc/min) circulation rate that is commonly produced for this lift and solution with the jet-assisted airlift sample system that is normally used at ICPP. The volume of the sample taken with a fluidic sampler is dependant on the motive pressure to the fluidic sampler, the sample bottle size and on the fluidic sampler jet characteristics. The fluidic sampler should be supplied with fluid having the motive pressure of the 140-150 percent of the peak vacuum producing motive pressure for the jet in the sampler. Fluidic transfer systems should be operated by emptying a full pumping chamber to nearly empty or empty during the pumping cycle, this maximizes the solution transfer rate.

  10. Home Fires Involving Grills

    MedlinePlus

    ... fires were fueled by gas while 13% used charcoal or other solid fuel. Gas grills were involved ... structure fires and 4,300 outdoor fires annually. Charcoal or other solid-fueled grills were involved in ...

  11. Novel sampling methods for use with thermal desorption ion trap mass spectrometry

    SciTech Connect

    Barshick, S.A.; Buchanan, M.V.

    1994-12-31

    Novel sampling approaches have been investigated to improve the analytical utility of thermal desorption Direct Sampling Ion Trap Mass Spectrometry (DSITMS). Because DSITMS involves the direct introduction of samples into an ion trap mass spectrometer, problems with detection capabilities (sensitivity and selectivity) can often occur when performing trace analysis in complex matrices. Various sampling approaches have been evaluated to improve thermal desorption detection capabilities and to extend the utilities of DSITMS methodologies without significantly increasing analysis times or the cost-effectiveness of DSITMS methods. Three sampling approaches have been investigated including solid phase microextraction (SPME), solid phase extraction columns (SPEC), and purge and trap.

  12. Asthma, Allergic Rhinitis, and Sleep Problems in Urban Children

    PubMed Central

    Koinis-Mitchell, Daphne; Kopel, Sheryl J.; Boergers, Julie; Ramos, Kara; LeBourgeois, Monique; McQuaid, Elizabeth L.; Esteban, Cynthia A.; Seifer, Ronald; Fritz, Gregory K.; Klein, Robert B.

    2015-01-01

    Objectives: In this study, we examine the association of asthma (asthma symptoms, asthma control, lung function) and sleep problems in a group of urban children. The role of allergic rhinitis (AR), a comorbid condition of asthma, on children's sleep problems is also examined. Finally, we investigate whether sleep hygiene moderates the association between asthma and sleep problems, and whether there are differences in these associations based on ethnic background. Methods: Non-Latino White, Latino, and African American urban children with asthma (n = 195) ages 7–9 (47% female) and their primary caregivers participated in a baseline visit involving interview-based questionnaires on demographics, asthma and rhinitis control, and caregiver report of children's sleep problems and sleep hygiene. Children and their caregivers participated in a clinical evaluation of asthma and AR, followed by a month monitoring period of children's asthma using objective and subjective methods. Results: Total sleep problem scores were higher in children of the sample who were from African American and Latino backgrounds, compared to non-Latino white children. Poor asthma control was predictive of higher levels of sleep problems in the entire sample. Poorer AR control also was related to more sleep problems, over and above children's asthma in the sample. This association was more robust in non-Latino white children. Poor sleep hygiene heightened the association between poor asthma control and sleep problems in the entire sample and in African American children. Conclusions: Multidisciplinary interventions integrating the co-management of asthma, AR, and the effects of both illnesses on children's sleep, need to be developed and tailored to children and their families' ethnic background. Citation: Koinis-Mitchell D, Kopel SJ, Boergers J, Ramos K, LeBourgeois M, McQuaid EL, Esteban CA, Seifer R, Fritz GK, Klein RB. Asthma, allergic rhinitis, and sleep problems in urban children. J Clin

  13. MANUAL OF ANALYTICAL QUALITY CONTROL FOR PESTICIDES AND RELATED COMPOUNDS IN HUMAN AND ENVIRONMENTAL SAMPLES. A COMPENDIUM OF SYSTEMATIC PROCEDURES DESIGNED TO ASSIST IN THE PREVENTION AND CONTROL OF ANALYTICAL PROBLEMS

    EPA Science Inventory

    This manual provides the pesticide chemist with a systematic protocol for the quality control of analytical procedures and the problems that arise in the analysis of human or environmental media. It also serves as a guide to the latest and most reliable methodology available for ...

  14. Involving Latino Parents.

    ERIC Educational Resources Information Center

    Quezada, Reyes L.; Diaz, Delia M.; Sanchez, Maria

    2003-01-01

    Describes barriers to Latino parent involvement in educational activities, factors to consider when involving Latino parents, and two examples of Latino involvement programs in California: Family Literacy Workshop at James Monroe Elementary School, Madera Unified School District, and Parents Take P.A.R.T. (Parent Assisted Reading Training) at…

  15. Affective Involvement Instrument.

    ERIC Educational Resources Information Center

    Lemlech, Johanna K.

    1970-01-01

    The Affective Involvement Instrument (AII) describes and classifies affective involvement in the process of decision-making as it occurs during classroom activities such as role-playing or group discussions. The thirty-celled instrument behaviorizes the six processes involved in decision-making and combines them with the taxonomic levels of the…

  16. Sampling apparatus

    DOEpatents

    Gordon, Norman R.; King, Lloyd L.; Jackson, Peter O.; Zulich, Alan W.

    1989-01-01

    A sampling apparatus is provided for sampling substances from solid surfaces. The apparatus includes first and second elongated tubular bodies which telescopically and sealingly join relative to one another. An absorbent pad is mounted to the end of a rod which is slidably received through a passageway in the end of one of the joined bodies. The rod is preferably slidably and rotatably received through the passageway, yet provides a selective fluid tight seal relative thereto. A recess is formed in the rod. When the recess and passageway are positioned to be coincident, fluid is permitted to flow through the passageway and around the rod. The pad is preferably laterally orientable relative to the rod and foldably retractable to within one of the bodies. A solvent is provided for wetting of the pad and solubilizing or suspending the material being sampled from a particular surface.

  17. Sampling apparatus

    DOEpatents

    Gordon, N.R.; King, L.L.; Jackson, P.O.; Zulich, A.W.

    1989-07-18

    A sampling apparatus is provided for sampling substances from solid surfaces. The apparatus includes first and second elongated tubular bodies which telescopically and sealingly join relative to one another. An absorbent pad is mounted to the end of a rod which is slidably received through a passageway in the end of one of the joined bodies. The rod is preferably slidably and rotatably received through the passageway, yet provides a selective fluid tight seal relative thereto. A recess is formed in the rod. When the recess and passageway are positioned to be coincident, fluid is permitted to flow through the passageway and around the rod. The pad is preferably laterally orientable relative to the rod and foldably retractable to within one of the bodies. A solvent is provided for wetting of the pad and solubilizing or suspending the material being sampled from a particular surface. 15 figs.

  18. SAMPLING OSCILLOSCOPE

    DOEpatents

    Sugarman, R.M.

    1960-08-30

    An oscilloscope is designed for displaying transient signal waveforms having random time and amplitude distributions. The oscilloscopc is a sampling device that selects for display a portion of only those waveforms having a particular range of amplitudes. For this purpose a pulse-height analyzer is provided to screen the pulses. A variable voltage-level shifter and a time-scale rampvoltage generator take the pulse height relative to the start of the waveform. The variable voltage shifter produces a voltage level raised one step for each sequential signal waveform to be sampled and this results in an unsmeared record of input signal waveforms. Appropriate delay devices permit each sample waveform to pass its peak amplitude before the circuit selects it for display.

  19. Puzzles & Problems.

    ERIC Educational Resources Information Center

    Murphy, Pat, Ed.

    1993-01-01

    "Exploring" is a magazine of science, art, and human perception, produced by Exploratorium in collaboration with other participating museums. This issue focuses on puzzles and problem solving. Brain teasers, puzzles, and the strategies for solving them are included. Features include: (1) "Homework Assignment #3" (Paul Doherty); (2) "The Case of…

  20. Heat Problems.

    ERIC Educational Resources Information Center

    Connors, G. Patrick

    Heat problems and heat cramps related to jogging can be caused by fluid imbalances, medications, dietary insufficiency, vomiting or diarrhea, among other factors. If the condition keeps reoccurring, the advice of a physician should be sought. Some preventive measures that can be taken include: (1) running during the cooler hours of the day; (2)…

  1. Music Taste Groups and Problem Behavior.

    PubMed

    Mulder, Juul; Bogt, Tom Ter; Raaijmakers, Quinten; Vollebergh, Wilma

    2007-04-01

    Internalizing and externalizing problems differ by musical tastes. A high school-based sample of 4159 adolescents, representative of Dutch youth aged 12 to 16, reported on their personal and social characteristics, music preferences and social-psychological functioning, measured with the Youth Self-Report (YSR). Cluster analysis on their music preferences revealed six taste groups: Middle-of-the-road (MOR) listeners, Urban fans, Exclusive Rock fans, Rock-Pop fans, Elitists, and Omnivores. A seventh group of musically Low-Involved youth was added. Multivariate analyses revealed that when gender, age, parenting, school, and peer variables were controlled, Omnivores and fans within the Exclusive Rock groups showed relatively high scores on internalizing YSR measures, and social, thought and attention problems. Omnivores, Exclusive Rock, Rock-Pop and Urban fans reported more externalizing problem behavior. Belonging to the MOR group that highly appreciates the most popular, chart-based pop music appears to buffer problem behavior. Music taste group membership uniquely explains variance in both internalizing and externalizing problem behavior. PMID:27519030

  2. Contextual Problem Solving Model Origination

    ERIC Educational Resources Information Center

    Ernst, Jeremy V.

    2009-01-01

    Problem solving has become a central focus of instructional activity in technology education classrooms at all levels (Boser, 1993). Impact assessment considerations incorporating society, culture, and economics are factors that require high-level deliberation involving critical thinking and the implementation of problem solving strategy. The…

  3. Problem Solving, Scaffolding and Learning

    ERIC Educational Resources Information Center

    Lin, Shih-Yin

    2012-01-01

    Helping students to construct robust understanding of physics concepts and develop good solving skills is a central goal in many physics classrooms. This thesis examine students' problem solving abilities from different perspectives and explores strategies to scaffold students' learning. In studies involving analogical problem solving…

  4. Readiness for Solving Story Problems.

    ERIC Educational Resources Information Center

    Dunlap, William F.

    1982-01-01

    Readiness activities are described which are designed to help learning disabled (LD) students learn to perform computations in story problems. Activities proceed from concrete objects to numbers and involve the students in devising story problems. The language experience approach is incorporated with the enactive, iconic, and symbolic levels of…

  5. Ethics in research involving prisoners.

    PubMed

    Pont, Jörg

    2008-01-01

    Research involving prisoners repeatedly went astray during the last century, culminating in the cruel medical experiments inside the Nazi concentration camps that gave rise to the Nuremberg Code. However, prisoners continued to become victims of scientific exploitation by the rapidly evolving biomedical research industry. The common roots of these abuses were the flawed philosophy that the needs of the society outweigh the needs of the individual and the researchers' view that prisoners are cheap, easy to motivate and stable research subjects. Prisoners are vulnerable to exploitation and abuse by research because their freedom for consent can easily be undermined, and because of learning disabilities, illiteracy and language barriers prevailing within prisoner populations. Therefore, penal laws of some countries supported by a number of internationally agreed documents prohibit research involving prisoners completely. However, prisoners must also be regarded as vulnerable to the specific health problems in prisons, e.g. transmissible diseases, mental disorders and suicide - problems that need to be addressed by research involving prisoners. Additionally, the participation of prisoner patients in research they directly can benefit from should be provided. Hence, it must be a common objective to find the right balance between protection from exploitation and access to research beneficial to prisoners. PMID:19061061

  6. Sampling for area estimation: A comparison of full-frame sampling with the sample segment approach

    NASA Technical Reports Server (NTRS)

    Hixson, M.; Bauer, M. E.; Davis, B. J. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. Full-frame classifications of wheat and non-wheat for eighty counties in Kansas were repetitively sampled to simulate alternative sampling plans. Evaluation of four sampling schemes involving different numbers of samples and different size sampling units shows that the precision of the wheat estimates increased as the segment size decreased and the number of segments was increased. Although the average bias associated with the various sampling schemes was not significantly different, the maximum absolute bias was directly related to sampling size unit.

  7. Associations between Polygenic Risk for Psychiatric Disorders and Substance Involvement

    PubMed Central

    Carey, Caitlin E.; Agrawal, Arpana; Bucholz, Kathleen K.; Hartz, Sarah M.; Lynskey, Michael T.; Nelson, Elliot C.; Bierut, Laura J.; Bogdan, Ryan

    2016-01-01

    Despite evidence of substantial comorbidity between psychiatric disorders and substance involvement, the extent to which common genetic factors contribute to their co-occurrence remains understudied. In the current study, we tested for associations between polygenic risk for psychiatric disorders and substance involvement (i.e., ranging from ever-use to severe dependence) among 2573 non-Hispanic European–American participants from the Study of Addiction: Genetics and Environment. Polygenic risk scores (PRS) for cross-disorder psychopathology (CROSS) were generated based on the Psychiatric Genomics Consortium’s Cross-Disorder meta-analysis and then tested for associations with a factor representing general liability to alcohol, cannabis, cocaine, nicotine, and opioid involvement (GENSUB). Follow-up analyses evaluated specific associations between each of the five psychiatric disorders which comprised CROSS—attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (AUT), bipolar disorder (BIP), major depressive disorder (MDD), and schizophrenia (SCZ)—and involvement with each component substance included in GENSUB. CROSS PRS explained 1.10% of variance in GENSUB in our sample (p < 0.001). After correction for multiple testing in our follow-up analyses of polygenic risk for each individual disorder predicting involvement with each component substance, associations remained between: (A) MDD PRS and non-problem cannabis use, (B) MDD PRS and severe cocaine dependence, (C) SCZ PRS and non-problem cannabis use and severe cannabis dependence, and (D) SCZ PRS and severe cocaine dependence. These results suggest that shared covariance from common genetic variation contributes to psychiatric and substance involvement comorbidity. PMID:27574527

  8. Associations between Polygenic Risk for Psychiatric Disorders and Substance Involvement.

    PubMed

    Carey, Caitlin E; Agrawal, Arpana; Bucholz, Kathleen K; Hartz, Sarah M; Lynskey, Michael T; Nelson, Elliot C; Bierut, Laura J; Bogdan, Ryan

    2016-01-01

    Despite evidence of substantial comorbidity between psychiatric disorders and substance involvement, the extent to which common genetic factors contribute to their co-occurrence remains understudied. In the current study, we tested for associations between polygenic risk for psychiatric disorders and substance involvement (i.e., ranging from ever-use to severe dependence) among 2573 non-Hispanic European-American participants from the Study of Addiction: Genetics and Environment. Polygenic risk scores (PRS) for cross-disorder psychopathology (CROSS) were generated based on the Psychiatric Genomics Consortium's Cross-Disorder meta-analysis and then tested for associations with a factor representing general liability to alcohol, cannabis, cocaine, nicotine, and opioid involvement (GENSUB). Follow-up analyses evaluated specific associations between each of the five psychiatric disorders which comprised CROSS-attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (AUT), bipolar disorder (BIP), major depressive disorder (MDD), and schizophrenia (SCZ)-and involvement with each component substance included in GENSUB. CROSS PRS explained 1.10% of variance in GENSUB in our sample (p < 0.001). After correction for multiple testing in our follow-up analyses of polygenic risk for each individual disorder predicting involvement with each component substance, associations remained between: (A) MDD PRS and non-problem cannabis use, (B) MDD PRS and severe cocaine dependence, (C) SCZ PRS and non-problem cannabis use and severe cannabis dependence, and (D) SCZ PRS and severe cocaine dependence. These results suggest that shared covariance from common genetic variation contributes to psychiatric and substance involvement comorbidity. PMID:27574527

  9. Individualized Math Problems in Logarithms. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    THis is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume includes problems involving logarithms, exponents, and…

  10. Individualized Math Problems in Ratio and Proportion. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This volume contains problems involving ratio and proportion. Some…

  11. Individualized Math Problems in Fractions. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. This package contains problems involving computation with common…

  12. Individualized Math Problems in Whole Numbers. Oregon Vo-Tech Mathematics Problem Sets.

    ERIC Educational Resources Information Center

    Cosler, Norma, Ed.

    This is one of eighteen sets of individualized mathematics problems developed by the Oregon Vo-Tech Math Project. Each of these problem packages is organized around a mathematical topic and contains problems related to diverse vocations. Solutions are provided for all problems. Problems in this set require computations involving whole numbers.…

  13. Enhancing chemistry problem-solving achievement using problem categorization

    NASA Astrophysics Data System (ADS)

    Bunce, Diane M.; Gabel, Dorothy L.; Samuel, John V.

    The enhancement of chemistry students' skill in problem solving through problem categorization is the focus of this study. Twenty-four students in a freshman chemistry course for health professionals are taught how to solve problems using the explicit method of problem solving (EMPS) (Bunce & Heikkinen, 1986). The EMPS is an organized approach to problem analysis which includes encoding the information given in a problem (Given, Asked For), relating this to what is already in long-term memory (Recall), and planning a solution (Overall Plan) before a mathematical solution is attempted. In addition to the EMPS training, treatment students receive three 40-minute sessions following achievement tests in which they are taught how to categorize problems. Control students use this time to review the EMPS solutions of test questions. Although problem categorization is involved in one section of the EMPS (Recall), treatment students who received specific training in problem categorization demonstrate significantly higher achievement on combination problems (those problems requiring the use of more than one chemical topic for their solution) at (p = 0.01) than their counterparts. Significantly higher achievement for treatment students is also measured on an unannounced test (p = 0.02). Analysis of interview transcripts of both treatment and control students illustrates a Rolodex approach to problem solving employed by all students in this study. The Rolodex approach involves organizing equations used to solve problems on mental index cards and flipping through them, matching units given when a new problem is to be solved. A second phenomenon observed during student interviews is the absence of a link in the conceptual understanding of the chemical concepts involved in a problem and the problem-solving skills employed to correctly solve problems. This study shows that explicit training in categorization skills and the EMPS can lead to higher achievement in complex problem

  14. The Problem of Managing a Strategic Reserve.

    ERIC Educational Resources Information Center

    Cole, David; And Others

    1986-01-01

    The problem of managing the reserve of cobalt is presented, followed by a method for bringing the stockpiled amount from any level to a desired goal. Solving a stochastic programming problem is involved. The procedure is discussed in detail. (MNS)

  15. Word Problems: A "Meme" for Our Times.

    ERIC Educational Resources Information Center

    Leamnson, Robert N.

    1996-01-01

    Discusses a novel approach to word problems that involves linear relationships between variables. Argues that working stepwise through intermediates is the way our minds actually work and therefore this should be used in solving word problems. (JRH)

  16. Extraction of aflatoxins from food samples using graphene-based magnetic nanosorbents followed by high-performance liquid chromatography: a simple solution to overcome the problems of immunoaffinity columns.

    PubMed

    Es'haghi, Zarrin; Beheshti, Hamed Reza; Feizy, Javad

    2014-09-01

    In this research, magnetic graphene nanoparticles were prepared and used as adsorbents for preconcentrating the aflatoxins in rice, wheat, and sesame samples. For this purpose, graphene was synthesized by Hummer's method. Magnetically modified graphene formed by the deposition of magnetite (Fe3O4) on graphene was used for the separation of aflatoxins B1, B2, G1, and G2 from the samples. The extractants were subsequently analyzed with high-performance liquid chromatography and fluorescence detection. Parameters affecting the efficiency of the method were thoroughly investigated. The measurements were done under the optimized conditions. For aflatoxins B1, B2, G1, and G2, limits of detection were 0.025, 0.05, 0.05, and 0.075 ng/g and limits of quantification were 0.083, 0.16, 0.16, and 0.23 ng/g, respectively. Accuracy was examined by the determination of the relative recovery of the aflatoxins. The relative recovery of aflatoxins B1, B2, G1, and G2 were quite satisfactory (between 64.38 and 122.21% for food samples). Relative standard deviations for within laboratory repeatability (n = 6) were in the range from 1.3 to 3.2. The application of this sorbent for the separation and concentration of the mentioned aflatoxins from food samples was examined. PMID:24975571

  17. Research on Computers and Problem Solving.

    ERIC Educational Resources Information Center

    Burton, John K.; And Others

    1988-01-01

    Eight articles review and report on research involving computers and problem solving skills. Topics discussed include research design; problem solving skills and programing languages, including BASIC and LOGO; computer anxiety; diagnostic programs for arithmetic problems; and relationships between ability and problem solving scores and between…

  18. "Seed Problems" in the Teaching of Mathematics.

    ERIC Educational Resources Information Center

    McLoughlin, Patrick

    1987-01-01

    The technique of using "seed problems" involves starting with a simple problem and seeing how far it leads. It may inspire different, related problems, or it may be approached with varied tools. Problems related to points and lines, pyramids, Pythagorean quadruples, and regular pentagons are discussed. (MNS)

  19. African American fathers and incarceration: paternal involvement and child outcomes.

    PubMed

    Perry, Armon R; Bright, Mikia

    2012-01-01

    Despite only accounting for 6% of the general population, African American males represent nearly 50% of the prison population. To investigate the impact of mass incarceration on African American families, data from the Fragile Families and Child Well-Being study were analyzed. Specifically, the purpose of this study was to examine the impact of previous incarceration on African American fathers' instrumental and affective involvement with their children, and the extent to which their previous incarceration influences their children's behavior. Results revealed that 51% of the fathers in the sample had been incarcerated by their child's fifth birthday. The results also revealed that these fathers fared worse economically and were less involved with their children. Moreover, the children of previously incarcerated fathers had significantly worse behavioral problems than the children of fathers who had never been incarcerated. PMID:22239385

  20. SOIL AND SEDIMENT SAMPLING METHODS

    EPA Science Inventory

    The EPA Office of Solid Waste and Emergency Response's (OSWER) Office of Superfund Remediation and Technology Innovation (OSRTI) needs innovative methods and techniques to solve new and difficult sampling and analytical problems found at the numerous Superfund sites throughout th...

  1. Multiple Matrix Sampling Applied to Needs Analysis: An Introduction and Assessment of Efficacy.

    ERIC Educational Resources Information Center

    Misanchuk, Earl R.

    A common approach to needs analysis involves the development of a self-report questionnaire administered to members of the intended audience. Such an approach poses a problem however: Concern for data reliability demands polling as many respondents as possible, while concern for cost-effectiveness dictates minimizing the size of the sample. The…

  2. Instructional Effects on Performance in a Matching-to-Sample Study

    ERIC Educational Resources Information Center

    Drake, Chad E.; Wilson, Kelly G.

    2008-01-01

    Conducting studies using an undergraduate participant pool is fraught with difficulties. Among them are problems with adequately motivating subjects both to come to the study, and once there, to actively engage the experimental task. Thirty-one college students participated in a matching-to-sample (MTS) study involving substantial training,…

  3. Sampling Strategy

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Three locations to the right of the test dig area are identified for the first samples to be delivered to the Thermal and Evolved Gas Analyzer (TEGA), the Wet Chemistry Lab (WCL), and the Optical Microscope (OM) on NASA's Phoenix Mars Lander. These sampling areas are informally labeled 'Baby Bear', 'Mama Bear', and 'Papa Bear' respectively. This image was taken on the seventh day of the Mars mission, or Sol 7 (June 1, 2008) by the Surface Stereo Imager aboard NASA's Phoenix Mars Lander.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. DIAMONDS: a new Bayesian nested sampling tool

    NASA Astrophysics Data System (ADS)

    Corsaro, Enrico; De Ridder, Joris

    2015-09-01

    In the context of high-quality asteroseismic data provided by the NASA Kepler Mission, we developed a new code, termed DIAMONDS (high-DImensional And multi-MOdal NesteD Sampling), for fast Bayesian parameter estimation and model comparison by means of the Nested Sampling Monte Carlo (NSMC) algorithm, an efficient and powerful method very suitable for high-dimensional problems (like the peak bagging analysis of solar-like oscillations) and multi-modal problems (i.e. problems that show multiple solutions). We applied the code to the peak bagging analysis of solar-like oscillations observed in a challenging F-type star. By means of DIAMONDS one is able to detect the different backgrounds in the power spectrum of the star (e.g. stellar granulation and faculae activity) and to understand whether one or two oscillation peaks can be identified or not. In addition, we demonstrate a novel approach to peak bagging based on multi-modality, which is able to reduce significantly the number of free parameters involved in the peak bagging model. This novel approach is therefore of great interest for possible future automatization of the entire analysis technique. Software package available at the DIAMONDS code website: http://https://fys.kuleuven.be/ster/Software/Diamonds/.

  5. Gene-by-Preschool Interaction on the Development of Early Externalizing Problems

    ERIC Educational Resources Information Center

    Tucker-Drob, Elliot M.; Harden, K. Paige

    2013-01-01

    Background: Preschool involves an array of new social experiences that may impact the development of early externalizing behavior problems over the transition to grade school. Methods: Using longitudinal data from a nationally representative sample of over 600 pairs of US twins, we tested whether the genetic and environmental influences on…

  6. Bidirectional Associations between Temperament and Parenting and the Prediction of Adjustment Problems in Middle Childhood

    ERIC Educational Resources Information Center

    Lengua, L.J.; Kovacs, E.A.

    2005-01-01

    This study examined longitudinal associations between child temperament (fearfulness, irritability, positive emotionality, self-regulation) and parenting (acceptance, involvement, inconsistent discipline) in predicting children's internalizing and externalizing problems using a community sample (N = 92) of children (ages 8-11) and their mothers.…

  7. Gender Differences in Mathematics Achievement and Retention Scores: A Case of Problem-Based Learning Method

    ERIC Educational Resources Information Center

    Ajai, John T.; Imoko, Benjamin I.

    2015-01-01

    This study was undertaken to assess gender differences in mathematics achievement and retention by using Problem-Based Learning (PBL). The design of the study was pre-posttest quasi-experimental. Four hundred and twenty eight senior secondary one (SS I) students using multistage sampling from ten grant-aided and government schools were involved in…

  8. Premature Adolescent Autonomy: Parent Disengagement and Deviant Peer Process in the Amplification of Problem Behaviour

    ERIC Educational Resources Information Center

    Dishion, Thomas J.; Nelson, Sarah E.; Bullock, Bernadette Marie

    2004-01-01

    Premature autonomy describes a developmental dynamic where parents of high-risk adolescents reduce their involvement and guidance when confronted with challenges of problem behaviour and the influence of deviant friendships. This dynamic was tested on the sample of Oregon Youth Study boys (N=206), whose family management practices and friendships…

  9. The Association between Parental Personality Patterns and Internalising and Externalising Behaviour Problems in Children and Adolescents

    ERIC Educational Resources Information Center

    Bertino, Melanie D.; Connell, Gabrielle; Lewis, Andrew J.

    2012-01-01

    Background: This study investigated the relationship between parental personality patterns and internalising and externalising behaviour problems in a clinically referred sample of children (aged 4-8) and adolescents (aged 12-18). Methods: Data from families involved in two clinical trials in Victoria, Australia were analysed (n = 59). Families…

  10. Protective Factors Associated with Fewer Multiple Problem Behaviors Among Homeless/Runaway Youth

    PubMed Central

    Lightfoot, Marguerita; Stein, Judith A.; Tevendale, Heather; Preston, Kathleen

    2015-01-01

    Although homeless youth exhibit numerous problem behaviors, protective factors that can be targeted and modified by prevention programs to decrease the likelihood of involvement in risky behaviors are less apparent. The current study tested a model of protective factors for multiple problem behavior in a sample of 474 homeless youth (42% girls; 83% minority) ages 12 to 24 years. Higher levels of problem solving and planning skills were strongly related to lower levels of multiple problem behaviors in homeless youth, suggesting both the positive impact of preexisting personal assets of these youth and important programmatic targets for further building their resilience and decreasing problem behaviors. Indirect relationships between the background factors of self-esteem and social support and multiple problem behaviors were significantly mediated through protective skills. The model suggests that helping youth enhance their skills in goal setting, decision making, and self-reliant coping could lessen a variety of problem behaviors commonly found among homeless youth. PMID:22023279

  11. Ear recognition from one sample per person.

    PubMed

    Chen, Long; Mu, Zhichun; Zhang, Baoqing; Zhang, Yi

    2015-01-01

    Biometrics has the advantages of efficiency and convenience in identity authentication. As one of the most promising biometric-based methods, ear recognition has received broad attention and research. Previous studies have achieved remarkable performance with multiple samples per person (MSPP) in the gallery. However, most conventional methods are insufficient when there is only one sample per person (OSPP) available in the gallery. To solve the OSPP problem by maximizing the use of a single sample, this paper proposes a hybrid multi-keypoint descriptor sparse representation-based classification (MKD-SRC) ear recognition approach based on 2D and 3D information. Because most 3D sensors capture 3D data accessorizing the corresponding 2D data, it is sensible to use both types of information. First, the ear region is extracted from the profile. Second, keypoints are detected and described for both the 2D texture image and 3D range image. Then, the hybrid MKD-SRC algorithm is used to complete the recognition with only OSPP in the gallery. Experimental results on a benchmark dataset have demonstrated the feasibility and effectiveness of the proposed method in resolving the OSPP problem. A Rank-one recognition rate of 96.4% is achieved for a gallery of 415 subjects, and the time involved in the computation is satisfactory compared to conventional methods. PMID:26024226

  12. Ear Recognition from One Sample Per Person

    PubMed Central

    Chen, Long; Mu, Zhichun; Zhang, Baoqing; Zhang, Yi

    2015-01-01

    Biometrics has the advantages of efficiency and convenience in identity authentication. As one of the most promising biometric-based methods, ear recognition has received broad attention and research. Previous studies have achieved remarkable performance with multiple samples per person (MSPP) in the gallery. However, most conventional methods are insufficient when there is only one sample per person (OSPP) available in the gallery. To solve the OSPP problem by maximizing the use of a single sample, this paper proposes a hybrid multi-keypoint descriptor sparse representation-based classification (MKD-SRC) ear recognition approach based on 2D and 3D information. Because most 3D sensors capture 3D data accessorizing the corresponding 2D data, it is sensible to use both types of information. First, the ear region is extracted from the profile. Second, keypoints are detected and described for both the 2D texture image and 3D range image. Then, the hybrid MKD-SRC algorithm is used to complete the recognition with only OSPP in the gallery. Experimental results on a benchmark dataset have demonstrated the feasibility and effectiveness of the proposed method in resolving the OSPP problem. A Rank-one recognition rate of 96.4% is achieved for a gallery of 415 subjects, and the time involved in the computation is satisfactory compared to conventional methods. PMID:26024226

  13. High Involvement Work Teams.

    ERIC Educational Resources Information Center

    1996

    These three papers were presented at a symposium on high-involvement work teams moderated by Michael Leimbach at the 1996 conference of the Academy of Human Resource Development. "Beyond Training to the New Learning Environment: Workers on the High-Involvement Frontline" (Joseph Anthony Ilacqua, Carol Ann Zulauf) shows the link between an…

  14. Parent Involvement Handbook.

    ERIC Educational Resources Information Center

    Caplan, Arna

    This handbook on parent involvement, designed to be used with preschool programs, was developed by the Jefferson County Public Schools in Lakewood, Colorado. Included are: (1) a general statement about parent involvement in an early childhood program, (2) a description of the Jefferson County Early Childhood Program, (3) a description of the…

  15. Commericial Involvement in Intramurals.

    ERIC Educational Resources Information Center

    Maas, Gerry

    Sport in general has long had ties with commercial interests, the most popular and widespread involving publicity. Intramural sports programs, however, have not cultivated many commercial involvements in publicity. The approach in intramural sports advertising is simple. A commercial interest pays for space or time in a given communication media…

  16. [Families Involved in Learning.

    ERIC Educational Resources Information Center

    Ashby, Nicole, Ed.

    2001-01-01

    This issue of "Community Update" focuses on families involved in learning. The first article briefly discusses the "Ready to Read, Ready to Learn" White House summit that highlighted new research on early childhood learning. The center spread of this issue offers "Priming the Primary Educator: A Look at L. A. County's Parent Involvement Programs"…

  17. Conversational Involvement and Loneliness.

    ERIC Educational Resources Information Center

    Bell, Robert A.

    1985-01-01

    Assessed the relationship of conversational involvement and loneliness among college students. Found that lonely participants in this study had lower rates of talkativeness, interruptions, and attention than the nonlonely; they were also perceived as less involved and less interpersonally attractive. (PD)

  18. Annealed Importance Sampling Reversible Jump MCMC algorithms

    SciTech Connect

    Karagiannis, Georgios; Andrieu, Christophe

    2013-03-20

    It will soon be 20 years since reversible jump Markov chain Monte Carlo (RJ-MCMC) algorithms have been proposed. They have significantly extended the scope of Markov chain Monte Carlo simulation methods, offering the promise to be able to routinely tackle transdimensional sampling problems, as encountered in Bayesian model selection problems for example, in a principled and flexible fashion. Their practical efficient implementation, however, still remains a challenge. A particular difficulty encountered in practice is in the choice of the dimension matching variables (both their nature and their distribution) and the reversible transformations which allow one to define the one-to-one mappings underpinning the design of these algorithms. Indeed, even seemingly sensible choices can lead to algorithms with very poor performance. The focus of this paper is the development and performance evaluation of a method, annealed importance sampling RJ-MCMC (aisRJ), which addresses this problem by mitigating the sensitivity of RJ-MCMC algorithms to the aforementioned poor design. As we shall see the algorithm can be understood as being an “exact approximation” of an idealized MCMC algorithm that would sample from the model probabilities directly in a model selection set-up. Such an idealized algorithm may have good theoretical convergence properties, but typically cannot be implemented, and our algorithms can approximate the performance of such idealized algorithms to an arbitrary degree while not introducing any bias for any degree of approximation. Our approach combines the dimension matching ideas of RJ-MCMC with annealed importance sampling and its Markov chain Monte Carlo implementation. We illustrate the performance of the algorithm with numerical simulations which indicate that, although the approach may at first appear computationally involved, it is in fact competitive.

  19. Development of adolescent problem behavior.

    PubMed

    Ary, D V; Duncan, T E; Biglan, A; Metzler, C W; Noell, J W; Smolkowski, K

    1999-04-01

    The developmental model of adolescent antisocial behavior advanced by Patterson and colleagues (e.g., Patterson, Reid, & Dishion, 1992) appears to generalize the development of a diverse set of problem behaviors. Structural equation modeling methods were applied to 18-month longitudinal data from 523 adolescents. The problem behavior construct included substance use, antisocial behavior, academic failure, and risky sexual behavior. Families with high levels of conflict were less likely to have high levels of parent-child involvement. Such family conditions resulted in less adequate parental monitoring of adolescent behavior, making associations with deviant peers more likely. Poor parental monitoring and associations with deviant peers were strong predictors of engagement in problem behavior. These constructs accounted for 46% of the variance in problem behavior. Although association with deviant peers was the most proximal social influence on problem behavior, parental monitoring and family factors (conflict and involvement) were key parenting practices that influenced this developmental process. PMID:10400060

  20. Emerging drug problems in Asia

    PubMed Central

    Bart, Gavin

    2014-01-01

    This session, “Emerging Drug Problems in Asia,” focused on emerging drug problems in Asia. Dr. Juana Tomás-Rosselló discussed “East and Southeast Asia: Emerging Drug Problems and Response” and Dr. Wei J. Chen discussed “Ketamine Use among Regular Tobacco and Alcohol Users as Revealed by Respondent Driven Sampling in Taipei: Prevalence, Expectancy, and Users' Risky Decision Making.” PMID:25267884

  1. Hotelling's Single Sample T2.

    ERIC Educational Resources Information Center

    Lutz, J. Gary

    1979-01-01

    A specialized vector used to interpret rejected multivariate single sample hypotheses, introduced in an earlier article by the writer (EJ 097 103), is shown here to be equivalent to the vector that would be obtained if discriminant analysis techniques were to be applied to a single sample problem. (Author)

  2. Drug samples: friend or foe?

    PubMed

    Coolidge, Melvin P

    2002-07-01

    The common practice of drug manufacturers in providing 'free' samples to physicians has influenced the business of medicine in several ways. This article analyzes some of the pros and cons of drug sampling, including from professional, societal, economical, legal, and practical perspectives, and provides suggestions on how to dispense with some of the problems inherent in the current system. PMID:12847754

  3. Importance sampling : promises and limitations.

    SciTech Connect

    West, Nicholas J.; Swiler, Laura Painton

    2010-04-01

    Importance sampling is an unbiased sampling method used to sample random variables from different densities than originally defined. These importance sampling densities are constructed to pick 'important' values of input random variables to improve the estimation of a statistical response of interest, such as a mean or probability of failure. Conceptually, importance sampling is very attractive: for example one wants to generate more samples in a failure region when estimating failure probabilities. In practice, however, importance sampling can be challenging to implement efficiently, especially in a general framework that will allow solutions for many classes of problems. We are interested in the promises and limitations of importance sampling as applied to computationally expensive finite element simulations which are treated as 'black-box' codes. In this paper, we present a customized importance sampler that is meant to be used after an initial set of Latin Hypercube samples has been taken, to help refine a failure probability estimate. The importance sampling densities are constructed based on kernel density estimators. We examine importance sampling with respect to two main questions: is importance sampling efficient and accurate for situations where we can only afford small numbers of samples? And does importance sampling require the use of surrogate methods to generate a sufficient number of samples so that the importance sampling process does increase the accuracy of the failure probability estimate? We present various case studies to address these questions.

  4. Core sample extractor

    NASA Technical Reports Server (NTRS)

    Akins, James; Cobb, Billy; Hart, Steve; Leaptrotte, Jeff; Milhollin, James; Pernik, Mark

    1989-01-01

    The problem of retrieving and storing core samples from a hole drilled on the lunar surface is addressed. The total depth of the hole in question is 50 meters with a maximum diameter of 100 millimeters. The core sample itself has a diameter of 60 millimeters and will be two meters in length. It is therefore necessary to retrieve and store 25 core samples per hole. The design utilizes a control system that will stop the mechanism at a certain depth, a cam-linkage system that will fracture the core, and a storage system that will save and catalogue the cores to be extracted. The Rod Changer and Storage Design Group will provide the necessary tooling to get into the hole as well as to the core. The mechanical design for the cam-linkage system as well as the conceptual design of the storage device are described.

  5. Problems without Numbers--At First

    ERIC Educational Resources Information Center

    Hewitt, Paul G.

    2006-01-01

    Three sample physics problems are presented in this article. The solutions to the three problems addresses a major student difficulty in problem solving--knowing where to begin. The first suggested step is to begin by stating what is asked for. Step 2 is identifying the fundamental physics that underlies the problem situation. Step 3 is isolating…

  6. Eye Involvement in TSC

    MedlinePlus

    ... what we see to the brain via the optic nerve. Retinal and optic nerve involvement in TSC are well known today, ... hamartomas (non-cancerous tumors) of the retina or optic nerve. The most common type of retinal hamartoma ...

  7. Medical problems of musicians.

    PubMed

    Lockwood, A H

    1989-01-26

    Surveys of performing musicians indicate that almost half of them experience playing-related medical problems, some of which threaten or end their careers. Overuse injuries involving the muscle--tendon unit are the most common problem, with symptoms ranging from mild pain while the musician is playing to pain severe enough to preclude any use of the affected hand. String players are the most commonly affected, and percussionists the least. The most important predisposing characteristic is the use of repetitive movements during long hours of practice, but awkward body positions mandated by the shape and weight of the instrument, the technical difficulty of the repertoire, and unfamiliar instruments may also play a part. Women are more commonly affected than men. Rest is the cornerstone of therapy. Neural impingement syndromes affecting the median or ulnar nerves or the thoracic outlet affect many musicians. Focal dystonias may involve part or all of a hand or the muscles forming the embouchure (the position of the lips in wind players). These are very resistant to therapy and may terminate or drastically alter a career. Stress, especially performance anxiety, may impede performance. Beta-adrenergic blocking agents prevent the symptoms of performance anxiety and are frequently used by musicians without medical supervision. A recognition of the unique problems of musician-patients has led to the formation of successful specialty clinics in a number of cities. PMID:2643048

  8. Problem Solving in the General Mathematics Classroom

    ERIC Educational Resources Information Center

    Troutman, Andria Price; Lichtenberg, Betty Plunkett

    1974-01-01

    Five steps common to different problem solving models are listed. Next, seven specific abilities related to solving problems are discussed and examples given. Sample activities, appropriate to help in developing these specific abilities, are suggested. (LS)

  9. The Contribution of Game Genre and other Use Patterns to Problem Video Game Play among Adult Video Gamers

    PubMed Central

    Ream, Geoffrey; McGinsky, Elizabeth; Dunlap, Eloise

    2012-01-01

    Aims To assess the contribution of patterns of video game play, including game genre, involvement, and time spent gaming, to problem use symptomatology. Design Nationally representative survey. Setting Online. Participants Large sample (n=3,380) of adult video gamers in the US. Measurements Problem video game play (PVGP) scale, video game genre typology, use patterns (gaming days in the past month and hours on days used), enjoyment, consumer involvement, and background variables. Findings Study confirms game genre's contribution to problem use as well as demographic variation in play patterns that underlie problem video game play vulnerability. Conclusions Identification of a small group of game types positively correlated with problem use suggests new directions for research into the specific design elements and reward mechanics of “addictive” video games. Unique vulnerabilities to problem use among certain groups demonstrate the need for ongoing investigation of health disparities related to contextual dimensions of video game play. PMID:23284310

  10. Covariance Matrix Estimation for the Cryo-EM Heterogeneity Problem*

    PubMed Central

    Katsevich, E.; Katsevich, A.; Singer, A.

    2015-01-01

    In cryo-electron microscopy (cryo-EM), a microscope generates a top view of a sample of randomly oriented copies of a molecule. The problem of single particle reconstruction (SPR) from cryo-EM is to use the resulting set of noisy two-dimensional projection images taken at unknown directions to reconstruct the three-dimensional (3D) structure of the molecule. In some situations, the molecule under examination exhibits structural variability, which poses a fundamental challenge in SPR. The heterogeneity problem is the task of mapping the space of conformational states of a molecule. It has been previously suggested that the leading eigenvectors of the covariance matrix of the 3D molecules can be used to solve the heterogeneity problem. Estimating the covariance matrix is challenging, since only projections of the molecules are observed, but not the molecules themselves. In this paper, we formulate a general problem of covariance estimation from noisy projections of samples. This problem has intimate connections with matrix completion problems and high-dimensional principal component analysis. We propose an estimator and prove its consistency. When there are finitely many heterogeneity classes, the spectrum of the estimated covariance matrix reveals the number of classes. The estimator can be found as the solution to a certain linear system. In the cryo-EM case, the linear operator to be inverted, which we term the projection covariance transform, is an important object in covariance estimation for tomographic problems involving structural variation. Inverting it involves applying a filter akin to the ramp filter in tomography. We design a basis in which this linear operator is sparse and thus can be tractably inverted despite its large size. We demonstrate via numerical experiments on synthetic datasets the robustness of our algorithm to high levels of noise. PMID:25699132

  11. Calculation of complex equilibria involving vaporization into vacuum

    NASA Technical Reports Server (NTRS)

    Paule, R. C.

    1974-01-01

    A simplified, direct approach is presented to the description of complex equilibria involving vaporization into vacuum. Emphasis is on the basic problem-solving process and on modification of existing techniques. Sequential solutions are presented to problems involving purification of a melt by vaporization into vacuum. The effects of concentration of melt and oxygen partial pressures on vaporization rates are demonstrated.

  12. New developments in sampling and aggregation for remotely sensed surveys

    NASA Technical Reports Server (NTRS)

    Feiveson, A. H. (Principal Investigator)

    1979-01-01

    Sampling techniques used to construct large area crop estimates are briefly reviewed. Problem areas in sampling and aggregation are covered. The natural sampling strategy, two phase sampling, weighted aggregation, and multiyear estimation are among the topics discussed.

  13. Principles for Sampling Airborne Radioactivity from Stacks

    SciTech Connect

    Glissmeyer, John A.

    2010-10-18

    This book chapter describes the special processes involved in sampling the airborne effluents from nuclear faciities. The title of the book is Radioactive Air Sampling Methods. The abstract for this chapter was cleared as PNNL-SA-45941.

  14. Attributes Heeded When Representing an Osmosis Problem.

    ERIC Educational Resources Information Center

    Zuckerman, June Trop

    Eighteen high school science students were involved in a study to determine what attributes in the problem statement they need when representing a typical osmosis problem. In order to realize this goal students were asked to solve problems aloud and to explain their answers. Included as a part of the results are the attributes that the students…

  15. Why Parental Involvement?

    ERIC Educational Resources Information Center

    Manno, Bruno V.

    Analysis of values, values transmission, human development, and Catholic social theory can increase effectiveness of parental involvement in Catholic education. Values are interpreted to include fundamental criteria which give meaning and order to life. Although values are transmitted by numerous sources including the family, social groups,…

  16. Involvement or Engagement?

    ERIC Educational Resources Information Center

    Ferlazzo, Larry

    2011-01-01

    To create the kinds of school-family partnerships that raise student achievement, improve local communities, and increase public support, schools need to understand the difference between family involvement and family engagement. Schools that emphasize the latter tend toward doing with families, rather than doing to families. These schools do more…

  17. Getting Parents Involved.

    ERIC Educational Resources Information Center

    Butts, Vickie; Finch, Patty A.

    1985-01-01

    Describes a parental involvement program in reading, writing, and human education. The project consists of caring for Clifford, a stuffed toy dog, on a rotated basis by first grade students. Books and pet care items accompany Clifford and provide an opportunity for parent and child to work together. (ML)

  18. Job Involvement of Teachers.

    ERIC Educational Resources Information Center

    Knoop, Robert

    This study investigated the relationship between job involvement and three sets of variables: nine personal (age, sex, marital status, education, overall experience, nonteaching experience, present school experience, income, and locus of control), three structural (size of school, location of school, and hierarchical position), and eight job…

  19. Strengthening Parent Involvement.

    ERIC Educational Resources Information Center

    Williams, David L., Jr.; Chavkin, Nancy Feyl

    1986-01-01

    Recent studies have verified Secretary of Education William Bennett's observation on the importance of home and family life. The most successful students are those whose parents become actively engaged in the educational process at home and at school. To capitalize on potential parent involvement, principals need to understand the kinds of…

  20. Immunobullous diseases with ocular involvement.

    PubMed

    Camisa, C; Meisler, D M

    1992-07-01

    Collaborative efforts of the dermatologist and ophthalmologist and other physicians with interest and experience in the management of the autoimmune bullous diseases optimize patient care by avoiding potentially harmful delay in diagnosis or implementation of therapy. At our institution, ophthalmologic and dermatologic follow-up visits for patients with bullous disorders involving the eyes are arranged for the same day so that ophthalmic examination and monitoring and adjustment of medication by the dermatologist can be effected. During initiation of treatment, visits are monthly. Later, when patients are stabilized, intervals may be extended to 3 to 6 months. More frequent visits are arranged as needed with the ophthalmologist to manage infectious complications or problems requiring surgical management and with the dermatologist to manage extraocular disease and adverse reactions to medication and to triage concurrent illnesses. PMID:1617813

  1. An inverse acoustic waveguide problem in the time domain

    NASA Astrophysics Data System (ADS)

    Monk, Peter; Selgas, Virginia

    2016-05-01

    We consider the problem of locating an obstacle in a waveguide from time domain measurements of causal waves. More precisely, we assume that we are given the scattered field due to point sources placed on a surface located inside the waveguide away from the obstacle, where the scattered field is measured on the same surface. From this multi-static scattering data we wish to determine the position and shape of an obstacle in the waveguide. To deal with this inverse problem, we adapt and analyze the time domain linear sampling method. This involves proving new time domain estimates for the forward problem, as well as analyzing several time domain operators arising in the inversion scheme. We also implement the inversion algorithm and provide numerical results in two-dimensions using synthetic data.

  2. Improving Reading Skills through Parental Involvement.

    ERIC Educational Resources Information Center

    Clark, Kathryn; Pillion, Jennifer

    This report describes a project for increasing parental involvement through the existing reading program. The targeted first and second grade students lived in growing rural, Midwestern, low to middle class communities located in north central Illinois. The problem was noted in literature by researchers who found that parents had a very limited…

  3. Improving Parental Involvement through School Sponsored Events.

    ERIC Educational Resources Information Center

    Anderson, Linda; Hicock, Mary Beth; McClellan, Kim

    This action research project sought to increase parental involvement in targeted kindergarten classrooms. Evidence for the problem included the lack of family attendance at school functions, declining membership in the parent-sponsored Booster Club, and lack of parental support for school policies. The project focused on three areas of parental…

  4. [Chronic diseases, functional ability, social involvement and satisfaction in community-dwelling elderly: the Fibra study].

    PubMed

    Pinto, Juliana Martins; Neri, Anita Liberalesso

    2013-12-01

    The scope of this article is to describe variations in the measurement of chronic diseases, functional ability, social involvement and satisfaction with respect to memory, problem solving, social relationships, environment, health services and transportation. This is done according to gender, age and income. It analyzes correlations between social involvement and functional ability in independent community dwelling-elderly aged 65 and above. 2,472 seniors without cognitive deficit, from probabilistic samples of seven Brazilian locations, were submitted to self-reported measurement concerning all variables, with the exception of grip strength and gait speed assessed by objective tests. Mean age was 72.2 ± 5.5 years and mean income was 3.9 ± 4.9 MW; 65.7% were women, who had more diseases, worse functional performance and greater social involvement than men; those aged 80 and above and the poorest participants had worse functional performance and less social involvement. Correlations were observed between functional ability and social involvement. Level of income was related to satisfaction concerning memory, problem solving, health and transport services. Health, functionality and satisfaction interact in old age, influencing patterns of activity and social involvement. PMID:24263862

  5. Getting involved in research.

    PubMed

    Banner, Davina; Grant, Lyle G

    2011-01-01

    The need for quality nursing research to promote evidence-based practice and optimize patient care is well recognized. This is particularly pertinent in cardiovascular nursing, where cardiovascular disease continues to be the leading cause of morbidity and mortality worldwide (World Health Organization, 2007). Across the spectrum of academic, clinical, and health care administration nursing roles, research remains fundamental to bridging theory, practice, and education (LoBiondo-Wood, Haber, Cameron, & Singh, 2009). Despite recognition of the importance of nursing research, the gap between research and practice continues to be an ongoing issue (Funk, Tornquist, & Champagne, 1995; Pettengill, Gillies, & Clark, 1994; Rizzuto, Bostrom, Suterm, & Chenitz, 1994; Rolfe, 1998). Nurses are appropriately situated to contribute to research that improves clinical outcomes and health service delivery. However, the majority of nurses in clinical practice do not have a significant research component structured into their nursing role. In this research column, the authors outline the importance of nurses being engaged in research and present some different levels of involvement that nurses may assume. A continuum of nursing research involvement includes asking researchable questions, being a savvy consumer of research evidence, finding your own level of research involvement, and aspiring to lead. PMID:21361237

  6. Optimal hemicube sampling

    SciTech Connect

    Max, N. |

    1992-12-17

    Radiosity algorithms for global illumination, either ``gathering`` or ``shooting`` versions, depend on the calculation of form factors. It is possible to calculate the form factors analytically, but this is difficult when occlusion is involved, so sampling methods are usually preferred. The necessary visibility information can be obtained by ray tracing in the sampled directions. However, area coherence makes it more efficient to project and scan-convert the scene onto a number of planes, for example, the faces of a hemicube. The hemicube faces have traditionally been divided into equal square pixels, but more general subdivisions are practical, and can reduce the variance of the form factor estimates. The hemicube estimates of form factors are based on a finite set of sample directions. We obtain several optimal arrangements of sample directions, which minimize the variance of this estimate. Four approaches are changing the size of the pixels, the shape of the pixels, the shape of the hemicube, or using non-uniform pixel grids. The best approach reduces the variance by 43%. The variance calculation is based on the assumption that the errors in the estimate are caused by the projections of single edges of polygonal patches, and that the positions and orientations of these edges are random.

  7. Optimal hemicube sampling

    SciTech Connect

    Max, N. California Univ., Davis, CA )

    1992-12-17

    Radiosity algorithms for global illumination, either gathering'' or shooting'' versions, depend on the calculation of form factors. It is possible to calculate the form factors analytically, but this is difficult when occlusion is involved, so sampling methods are usually preferred. The necessary visibility information can be obtained by ray tracing in the sampled directions. However, area coherence makes it more efficient to project and scan-convert the scene onto a number of planes, for example, the faces of a hemicube. The hemicube faces have traditionally been divided into equal square pixels, but more general subdivisions are practical, and can reduce the variance of the form factor estimates. The hemicube estimates of form factors are based on a finite set of sample directions. We obtain several optimal arrangements of sample directions, which minimize the variance of this estimate. Four approaches are changing the size of the pixels, the shape of the pixels, the shape of the hemicube, or using non-uniform pixel grids. The best approach reduces the variance by 43%. The variance calculation is based on the assumption that the errors in the estimate are caused by the projections of single edges of polygonal patches, and that the positions and orientations of these edges are random.

  8. The worldwide "wildfire" problem.

    PubMed

    Gill, A Malcolm; Stephens, Scott L; Cary, Geoffrey J

    2013-03-01

    The worldwide "wildfire" problem is headlined by the loss of human lives and homes, but it applies generally to any adverse effects of unplanned fires, as events or regimes, on a wide range of environmental, social, and economic assets. The problem is complex and contingent, requiring continual attention to the changing circumstances of stakeholders, landscapes, and ecosystems; it occurs at a variety of temporal and spatial scales. Minimizing adverse outcomes involves controlling fires and fire regimes, increasing the resistance of assets to fires, locating or relocating assets away from the path of fires, and, as a probability of adverse impacts often remains, assisting recovery in the short-term while promoting the adaptation of societies in the long-term. There are short- and long-term aspects to each aspect of minimization. Controlling fires and fire regimes may involve fire suppression and fuel treatments such as prescribed burning or non-fire treatments but also addresses issues associated with unwanted fire starts like arson. Increasing the resistance of assets can mean addressing the design and construction materials of a house or the use of personal protective equipment. Locating or relocating assets can mean leaving an area about to be impacted by fire or choosing a suitable place to live; it can also mean the planning of land use. Assisting recovery and promoting adaptation can involve insuring assets and sharing responsibility for preparedness for an event. There is no single, simple, solution. Perverse outcomes can occur. The number of minimizing techniques used, and the breadth and depth of their application, depends on the geographic mix of asset types. Premises for policy consideration are presented. PMID:23634593

  9. Continued detention involvement and adolescent marijuana use trajectories.

    PubMed

    Ewing, Sarah W Feldstein; Schmiege, Sarah J; Bryan, Angela D

    2014-01-01

    Justice-involved youth have high rates of marijuana use. Less is known about what may drive these rates, particularly when justice-involved youth return to the community. One factor that has been implicated is continued detention involvement. Yet, it is unknown how this factor may influence marijuana use trajectories. Using longitudinal growth curve modeling, the researchers evaluated the association between continued detention involvement and marijuana use trajectories in two large, ethnically diverse samples of community-based, justice-involved youth. Across both samples, marijuana use decreased over time for youth with continued detention involvement but did not change for youth without continued detention involvement. These findings underscore the importance of attending to the influence of detention involvement in community-based, justice-involved adolescents' marijuana use trajectories. This study also highlights the importance of coordinating prevention/intervention programming for justice-involved youth once they are in the community. PMID:24272742

  10. Breathing Problems: An Individualized Program.

    ERIC Educational Resources Information Center

    Vodola, Thomas M.

    As one of the components of the Project ACTIVE (All Children Totally Involved Exercising) Teacher Training Model Kit, the manual is designed to enable the educator to organize, conduct, and evaluate individualized-personalized physical education programs for children (prekindergarten through high school) with breathing problems. An introductory…

  11. PROBLEMS IN MODERN GREEK LEXICOGRAPHY.

    ERIC Educational Resources Information Center

    KAHANE, HENRY; KAHANE, RENEE

    PROBLEMS DEALING WITH LEVELS OF SPEECH AND LEVELS OF ANALYSIS IN CONNECTION WITH MODERN GREEK LEXICOGRAPHICAL STUDY WERE DISCUSSED. CONCERNING THE POSSIBLE CONSTRUCTION OF A COMPETENT BILINGUAL DICTIONARY, THE INVESTIGATORS SUGGESTED THAT THE VARIOUS STRUCTURES (NAMELY, PHONOLOGY, MORPHOLOGY, AND SYNTAX) BE TIED TOGETHER TO INVOLVE (1) LISTING IN…

  12. Acceptance sampling using judgmental and randomly selected samples

    SciTech Connect

    Sego, Landon H.; Shulman, Stanley A.; Anderson, Kevin K.; Wilson, John E.; Pulsipher, Brent A.; Sieber, W. Karl

    2010-09-01

    We present a Bayesian model for acceptance sampling where the population consists of two groups, each with different levels of risk of containing unacceptable items. Expert opinion, or judgment, may be required to distinguish between the high and low-risk groups. Hence, high-risk items are likely to be identifed (and sampled) using expert judgment, while the remaining low-risk items are sampled randomly. We focus on the situation where all observed samples must be acceptable. Consequently, the objective of the statistical inference is to quantify the probability that a large percentage of the unsampled items in the population are also acceptable. We demonstrate that traditional (frequentist) acceptance sampling and simpler Bayesian formulations of the problem are essentially special cases of the proposed model. We explore the properties of the model in detail, and discuss the conditions necessary to ensure that required samples sizes are non-decreasing function of the population size. The method is applicable to a variety of acceptance sampling problems, and, in particular, to environmental sampling where the objective is to demonstrate the safety of reoccupying a remediated facility that has been contaminated with a lethal agent.

  13. Do parents still matter? Parent and peer influences on alcohol involvement among recent high school graduates.

    PubMed

    Wood, Mark D; Read, Jennifer P; Mitchell, Roger E; Brand, Nancy H

    2004-03-01

    This study investigated the influences of peer and parent variables on alcohol use and problems in a sample of late adolescents in the summer immediately prior to entry into college. Participants (N = 556) completed a mail survey assessing peer influences (alcohol offers, social modeling, perceived norms), parental behaviors (nurturance, monitoring), and attitudes and values (disapproval for heavy drinking, permissiveness for drinking), and alcohol use and alcohol-related consequences. Hierarchical regression analyses indicated significant associations between both peer and parental influences and alcohol involvement, and showed that parental influences moderated peer-influence-drinking behavior, such that higher levels of perceived parental involvement were associated with weaker relations between peer influences and alcohol use and problems. These findings suggest that parents continue to exert an influential role in late adolescent drinking behavior. PMID:15008682

  14. Analog Processor To Solve Optimization Problems

    NASA Technical Reports Server (NTRS)

    Duong, Tuan A.; Eberhardt, Silvio P.; Thakoor, Anil P.

    1993-01-01

    Proposed analog processor solves "traveling-salesman" problem, considered paradigm of global-optimization problems involving routing or allocation of resources. Includes electronic neural network and auxiliary circuitry based partly on concepts described in "Neural-Network Processor Would Allocate Resources" (NPO-17781) and "Neural Network Solves 'Traveling-Salesman' Problem" (NPO-17807). Processor based on highly parallel computing solves problem in significantly less time.

  15. Sampling for area estimation: A comparison of full-frame sampling with the sample segment approach. [Kansas

    NASA Technical Reports Server (NTRS)

    Hixson, M. M.; Bauer, M. E.; Davis, B. J.

    1979-01-01

    The effect of sampling on the accuracy (precision and bias) of crop area estimates made from classifications of LANDSAT MSS data was investigated. Full-frame classifications of wheat and non-wheat for eighty counties in Kansas were repetitively sampled to simulate alternative sampling plants. Four sampling schemes involving different numbers of samples and different size sampling units were evaluated. The precision of the wheat area estimates increased as the segment size decreased and the number of segments was increased. Although the average bias associated with the various sampling schemes was not significantly different, the maximum absolute bias was directly related to sampling unit size.

  16. Sleep Problems in Individuals with Angelman Syndrome

    ERIC Educational Resources Information Center

    Didden, Robert; Korzilius, Hubert; Smits, Marcel G.; Curfs, Leopold M. G.

    2004-01-01

    Prevalence of severe sleep problems and its association with other variables were investigated with 109 individuals who have Angelman syndrome. Severe settling problems, frequent night waking, and early waking were found in 2%, 37%, and 10% of the individuals, respectively. Sleep problems were persistent in this sample. No statistically…

  17. Enhancing Paradynamics for QM/MM Sampling of Enzymatic Reactions.

    PubMed

    Lameira, Jerônimo; Kupchencko, Ilya; Warshel, Arieh

    2016-03-10

    Despite the enormous increase in computer power, it is still extremely challenging to obtain computationally converging sampling of ab initio QM/MM (QM(ai)/MM) free energy surfaces in condensed phases. The sampling problem can be significantly reduced by the use of the reference potential paradynamics (PD) approach, but even this approach still requires major computer time in studies of enzymatic reactions. To further reduce the sampling problem we developed here a new PD version where we use an empirical valence bond reference potential that has a minimum rather than a maximum at the transition state region of the target potential (this is accomplished conveniently by shifting the EVB of the product state). Hence, we can map the TS region in a more efficient way. Here, we introduce and validate the inverted EVB PD approach. The validation involves the study of the S(N)2 step of the reaction catalyzed by haloakene dehalogenase (DhlA) and the GTP hydrolysis in the RasGAP system. In addition, we have also studied the corresponding reaction in water for each of the systems described here and the reaction involving trimethylsulfonium and dimethylamine in solution. The results are encouraging and the new strategy appears to provide a powerful way of evaluating QM(ai)/MM activation free energies. PMID:26866994

  18. Bringing a Bayesian Perspective to Large Dimensional Problems in Geophysics

    NASA Astrophysics Data System (ADS)

    Duputel, Z.; Simons, M.; Jolivet, R.; Zaroli, C.; Rivera, L. A.; Ampuero, J. P.; Gombert, B.; Minson, S. E.

    2015-12-01

    The last decade has seen a substantial expansion of geophysical observations. Exploiting this wealth of data involves large ill-conditioned inverse problems requiring large numbers of uncertain parameters. A common approach in geophysics is to use some form of regularization that transforms the inversion into a well-conditioned optimization problem. While this approach is convenient and computationally inexpensive, the inherent non-uniqueness of our problems suggest that we should not simply search for a single optimal model, but rather attempt to describe the ensemble of plausible models that can fit the data and are consistent with prior information. This talk will present various applications of full Bayesian analysis techniques to large ill-posed inverse problems in geophysics. Despite significant computational cost, Bayesian sampling is a powerful tool to combine prior information, theoretical knowledge and data in order to address scientific problems probabilistically. We shall illustrate this by showing recent results for two types of problems: (1) the study of earthquakes sources and (2) imaging of the Earth interior. In particular, we will present different strategies that can be employed in order to achieve realistic uncertainty estimates.

  19. Endocannabinoid involvement in endometriosis

    PubMed Central

    Dmitrieva, Natalia; Nagabukuro, Hiroshi; Resuehr, David; Zhang, Guohua; McAllister, Stacy L.; McGinty, Kristina A.; Mackie, Ken; Berkley, Karen J.

    2010-01-01

    Endometriosis is a disease common in women that is defined by abnormal extrauteral growths of uterine endometrial tissue and associated with severe pain. Partly because how the abnormal growths become associated with pain is poorly understood, the pain is difficult to alleviate without resorting to hormones or surgery, which often produce intolerable side effects or fail to help. Recent studies in a rat model and women showed that sensory and sympathetic nerve fibers sprout branches to innervate the abnormal growths. This situation, together with knowledge that the endocannabinoid system is involved in uterine function and dysfunction and that exogenous cannabinoids were once used to alleviate endometriosis-associated pain, suggests that the endocannabinoid system is involved in both endometriosis and its associated pain. Here, using a rat model, we found that CB1 cannabinoid receptors are expressed on both the somata and fibers of both the sensory and sympathetic neurons that innervate endometriosis’s abnormal growths. We further found that CB1 receptor agonists decrease, whereas CB1 receptor antagonists increase, endometriosis-associated hyperalgesia. Together these findings suggest that the endocannabinoid system contributes to mechanisms underlying both the peripheral innervation of the abnormal growths and the pain associated with endometriosis, thereby providing a novel approach for the development of badly-needed new treatments. PMID:20833475

  20. Fatal incidents involving pickup trucks in Alabama.

    PubMed

    Hamar, G B; King, W; Bolton, A; Fine, P R

    1991-03-01

    Death or injury resulting from crashes involving light trucks (ie, pickup trucks) is a significant problem. Data show that fatal crashes and occupant fatalities involving light trucks have steadily increased since 1983. This project describes vehicle crashes involving passengers riding in the beds of pickup trucks. Actual crashes were identified through the Fatal Accident Reporting System (FARS) of the National Highway Traffic Safety Administration. The 40 incidents studied involved 204 pickup truck passengers. Of these, 45 were killed, 107 sustained visible injuries or were carried from the scene, 6 had bruises and abrasions, and 2 had no visible injury but were briefly unconscious or had a documented complaint of pain. The risk of death among pickup truck passengers who were fully ejected from the vehicle was nearly six times that of passengers not fully ejected. Correspondingly, the risk of ejection from the truck was 26.7 times greater among occupants riding in the bed than occupants riding in the cab. PMID:2000522

  1. Problem Behaviors among Israeli Undergraduate Students: Applying Jessor’s Problem Behavior Theory among Young Adult Students

    PubMed Central

    Korn, Liat; Shaked, Yael; Fogel-Grinvald, Haya

    2014-01-01

    Purpose: The current study tested the applicability of Jessor’s problem behavior theory (PBT) in Ariel University. Methods: A structured, self-reported, anonymous questionnaire was administered to undergraduate students. The final study sample included 1,360 participants (882 females and 478 males, mean age 25, SD = 2.9, range = 17). Results: Findings indicated that the PBT was replicated in this sample. As shown from the hierarchal linear regression model, religiosity and high-academic achievements were found to be strong and significant protective factors that reduce risk behaviors. Among young and religious students, the personal vulnerability has almost no impact on involvement in risk behaviors. Conclusion: The PBT finds empirical support in this young adult undergraduate Israeli sample. PMID:25566519

  2. Reduction of severe behavior problems in the community using a multicomponent treatment approach.

    PubMed Central

    Carr, E G; Carlson, J I

    1993-01-01

    Problem behavior often prevents community integration of people with developmental disabilities. Therefore, we evaluated a multicomponent approach for remediating problem behavior in public community settings (specifically, supermarkets). We selected treatments based on hypotheses about the variables controlling the problem behavior (hypothesis-driven model). The multicomponent intervention included choice making, embedding, functional communication training, building tolerance for delay of reinforcement, and presenting discriminative stimuli for nonproblem behavior. Treatment progress was monitored using measures of latency and task completion rather than traditional measures of frequency and time sampling. Results showed substantial increases in task completion and duration of time spent in supermarkets without problem behavior. Outcomes were socially validated by group-home staff and cashiers. We discuss how the intervention approach taken can resolve some of the issues involved in assessing, measuring, and treating problem behavior in the community. PMID:8331013

  3. Sampling and sample processing in pesticide residue analysis.

    PubMed

    Lehotay, Steven J; Cook, Jo Marie

    2015-05-13

    Proper sampling and sample processing in pesticide residue analysis of food and soil have always been essential to obtain accurate results, but the subject is becoming a greater concern as approximately 100 mg test portions are being analyzed with automated high-throughput analytical methods by agrochemical industry and contract laboratories. As global food trade and the importance of monitoring increase, the food industry and regulatory laboratories are also considering miniaturized high-throughput methods. In conjunction with a summary of the symposium "Residues in Food and Feed - Going from Macro to Micro: The Future of Sample Processing in Residue Analytical Methods" held at the 13th IUPAC International Congress of Pesticide Chemistry, this is an opportune time to review sampling theory and sample processing for pesticide residue analysis. If collected samples and test portions do not adequately represent the actual lot from which they came and provide meaningful results, then all costs, time, and efforts involved in implementing programs using sophisticated analytical instruments and techniques are wasted and can actually yield misleading results. This paper is designed to briefly review the often-neglected but crucial topic of sample collection and processing and put the issue into perspective for the future of pesticide residue analysis. It also emphasizes that analysts should demonstrate the validity of their sample processing approaches for the analytes/matrices of interest and encourages further studies on sampling and sample mass reduction to produce a test portion. PMID:25677085

  4. Improved sample size determination for attributes and variables sampling

    SciTech Connect

    Stirpe, D.; Picard, R.R.

    1985-01-01

    Earlier INMM papers have addressed the attributes/variables problem and, under conservative/limiting approximations, have reported analytical solutions for the attributes and variables sample sizes. Through computer simulation of this problem, we have calculated attributes and variables sample sizes as a function of falsification, measurement uncertainties, and required detection probability without using approximations. Using realistic assumptions for uncertainty parameters of measurement, the simulation results support the conclusions: (1) previously used conservative approximations can be expensive because they lead to larger sample sizes than needed; and (2) the optimal verification strategy, as well as the falsification strategy, are highly dependent on the underlying uncertainty parameters of the measurement instruments. 1 ref., 3 figs.

  5. The Effect of Learning Environments Based on Problem Solving on Students' Achievements of Problem Solving

    ERIC Educational Resources Information Center

    Karatas, Ilhan; Baki, Adnan

    2013-01-01

    Problem solving is recognized as an important life skill involving a range of processes including analyzing, interpreting, reasoning, predicting, evaluating and reflecting. For that reason educating students as efficient problem solvers is an important role of mathematics education. Problem solving skill is the centre of mathematics curriculum.…

  6. Problem-Based Learning: Using Ill-Structured Problems in Biology Project Work

    ERIC Educational Resources Information Center

    Chin, Christine; Chia, Li-Gek

    2006-01-01

    This case study involved year 9 students carrying out project work in biology via problem-based learning. The purpose of the study was to (a) find out how students approach and work through ill-structured problems, (b) identify some issues and challenges related to the use of such problems, and (c) offer some practical suggestions on the…

  7. STACK SAMPLING FOR ORGANIC EMISSIONS

    EPA Science Inventory

    The paper reviews some of the more important principles involved in stack sampling for organics, briefly describes and discusses recently developed equipment, and points out a few of the more serious pitfalls. Extensive references are provided, many of which are often overlooked ...

  8. Field techniques for sampling ants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ants occur in most environments and ecologists ask a diverse array of questions involving ants. Thus, a key consideration in ant studies is to match the environment and question (and associated environmental variables) to the ant sampling technique. Since each technique has distinct limitations, usi...

  9. Examining Understandings of Parent Involvement in Early Childhood Programs

    ERIC Educational Resources Information Center

    Hilado, Aimee V.; Kallemeyn, Leanne; Phillips, Lauren

    2013-01-01

    The importance of parent involvement in children's development and learning is increasingly recognized in the research literature and in federal and state policies; however, no unified definition of parent involvement exists. This study examined different understandings and definitions of parent involvement in a sample of administrators of…

  10. Dialect Features and Communication Problems in Linxian.

    ERIC Educational Resources Information Center

    Liu, William W.

    1979-01-01

    Analyzes the speech of three speakers of Linxian Chinese, indicating the dialect's features and the problems involved in communication between speakers of Linxian and speakers of Putonghua (or Standard Mandarin). (Author/AM)

  11. Advanced hierarchical distance sampling

    USGS Publications Warehouse

    Royle, Andy

    2016-01-01

    In this chapter, we cover a number of important extensions of the basic hierarchical distance-sampling (HDS) framework from Chapter 8. First, we discuss the inclusion of “individual covariates,” such as group size, in the HDS model. This is important in many surveys where animals form natural groups that are the primary observation unit, with the size of the group expected to have some influence on detectability. We also discuss HDS integrated with time-removal and double-observer or capture-recapture sampling. These “combined protocols” can be formulated as HDS models with individual covariates, and thus they have a commonality with HDS models involving group structure (group size being just another individual covariate). We cover several varieties of open-population HDS models that accommodate population dynamics. On one end of the spectrum, we cover models that allow replicate distance sampling surveys within a year, which estimate abundance relative to availability and temporary emigration through time. We consider a robust design version of that model. We then consider models with explicit dynamics based on the Dail and Madsen (2011) model and the work of Sollmann et al. (2015). The final major theme of this chapter is relatively newly developed spatial distance sampling models that accommodate explicit models describing the spatial distribution of individuals known as Point Process models. We provide novel formulations of spatial DS and HDS models in this chapter, including implementations of those models in the unmarked package using a hack of the pcount function for N-mixture models.

  12. Cardiac involvement in hemochromatosis.

    PubMed

    Gulati, Vinay; Harikrishnan, Prakash; Palaniswamy, Chandrasekar; Aronow, Wilbert S; Jain, Diwakar; Frishman, William H

    2014-01-01

    Cardiac hemochromatosis or primary iron-overload cardiomyopathy is an important and potentially preventable cause of heart failure. This is initially characterized by diastolic dysfunction and arrhythmias and in later stages by dilated cardiomyopathy. Diagnosis of iron overload is established by elevated transferrin saturation (>55%) and elevated serum ferritin (>300 ng/mL). Genetic testing for mutations in the HFE (high iron) gene and other proteins, such as hemojuvelin, transferrin receptor, and ferroportin, should be performed if secondary causes of iron overload are ruled out. Patients should undergo comprehensive 2D and Doppler echocardiography to evaluate their systolic and diastolic function. Newer modalities like strain imaging and speckle-tracking echocardiography hold promise for earlier detection of cardiac involvement. Cardiac magnetic resonance imaging with measurement of T2* relaxation times can help quantify myocardial iron overload. In addition to its value in diagnosis of cardiac iron overload, response to iron reduction therapy can be assessed by serial imaging. Therapeutic phlebotomy and iron chelation are the cornerstones of therapy. The average survival is less than a year in untreated patients with severe cardiac impairment. However, if treated early and aggressively, the survival rate approaches that of the regular heart failure population. PMID:24503941

  13. Innovative sample tracking for a project requiring thousands of samples

    SciTech Connect

    Jahnke, J.G.; Edlund, M.D.

    1994-12-31

    A large project spread over 9,800 square miles with 3,000 samples and 300 sites demanded creative tracking and accounting of the samples. To answer this need, an innovative sample data system was developed for this project which investigated potential environmental impacts at missile sites in South Dakota and Missouri. The system provided improved data quality, lower transcription and typographical errors, reduced field efforts, fast sample tracking, and reduced data entry. Samples of groundwater, soils, lagoon sludge and paint required analysis of up to 75 analytical parameters. A project of this scope presented many logistics and accounting challenges involving many sites, samples, analyses, and sampling teams under a fast-track schedule. During one phase over two weeks, three teams collected over 1,000 samples at over 100 sites. To address such a scope, an integrated data system was implemented using computerized label preparation, a sample tracking database, electronic chains-of-custody, and database storage of analytical results. Pollutants of concern are VOCs, metals, and diesel fuels.

  14. Mixed Methods Sampling: A Typology with Examples

    ERIC Educational Resources Information Center

    Teddlie, Charles; Yu, Fen

    2007-01-01

    This article presents a discussion of mixed methods (MM) sampling techniques. MM sampling involves combining well-established qualitative and quantitative techniques in creative ways to answer research questions posed by MM research designs. Several issues germane to MM sampling are presented including the differences between probability and…

  15. Revisiting the concept of the 'problem young driver' within the context of the 'young driver problem': who are they?

    PubMed

    Scott-Parker, B; Watson, B; King, M J; Hyde, M K

    2013-10-01

    For decades there have been two young driver concepts: the 'young driver problem' where the driver cohort represents a key problem for road safety; and the 'problem young driver' where a sub-sample of drivers represents the greatest road safety problem. Given difficulties associated with identifying and then modifying the behaviour of the latter group, broad countermeasures such as graduated driver licensing (GDL) have generally been relied upon to address the young driver problem. GDL evaluations reveal general road safety benefits for young drivers, yet they continue to be overrepresented in fatality and injury statistics. Therefore it is timely for researchers to revisit the 'problem young driver' concept to assess its potential countermeasure implications. This is particularly relevant within the context of broader countermeasures that have been designed to address the 'young driver problem' Personal characteristics, behaviours and attitudes of 378 Queensland novice drivers aged 17-25 years were explored during their pre-, Learner and Provisional 1 (intermediate) licence as part of a larger longitudinal project. Self-reported risky driving was measured by the Behaviour of Young Novice Drivers Scale (BYNDS), and five subscale scores were used to cluster the drivers into three groups (high risk n=49, medium risk n=163, low risk n=166). High risk 'problem young drivers' were characterised by greater self-reported pre-Licence driving, unsupervised Learner driving, and speeding, driving errors, risky driving exposure, crash involvement, and offence detection during the Provisional period. Medium risk drivers were also characterised by more risky road use than the low risk group. Interestingly problem young drivers appear to have some insight into their high-risk driving, since they report significantly greater intentions to bend road rules in future driving. The results suggest that tailored intervention efforts may need to target problem young drivers within the

  16. Class and Home Problems: Optimization Problems

    ERIC Educational Resources Information Center

    Anderson, Brian J.; Hissam, Robin S.; Shaeiwitz, Joseph A.; Turton, Richard

    2011-01-01

    Optimization problems suitable for all levels of chemical engineering students are available. These problems do not require advanced mathematical techniques, since they can be solved using typical software used by students and practitioners. The method used to solve these problems forces students to understand the trends for the different terms…

  17. Near-instantaneous Bayesian inversion and uncertainty estimation: Sampling from the prior

    NASA Astrophysics Data System (ADS)

    Valentine, A. P.; Kaeufl, P.; De Wit, R. W. L.; Trampert, J.

    2015-12-01

    Ideally, uncertainty estimation should be treated as an intrinsic part of solving an inverse problem, and techniques such as Markov Chain Monte Carlo (MCMC) inversion provide a route to achieving this. However, these approaches involve `posterior sampling', and the (often significant) computational investment is entirely targeted towards one specific dataset. In those cases where similar inverse problems must be solved repeatedly (perhaps for multiple locations on the Earth's surface), or where results must be obtained within very limited timescales (e.g. earthquake early warning), this presents a barrier to use of methods such as MCMC. In such cases, approaches based on `prior sampling' may be preferable. This separates the computationally-expensive step (generating samples in the joint data-model space) from the dataset-specific inversion stage, and permits one set of samples to be recycled for many different datasets. The essential difference between prior and posterior sampling is the stage at which the solution is conditioned on a given dataset. We show that prior sampling can be implemented effectively, using learning algorithms to assimilate and apply information on the mapping between data and model spaces. We illustrate that this can be successfully applied in a range of geophysical problems. By comparing solutions based on prior sampling to those obtained via posterior sampling, we show that results are compatible---although the less focussed nature of prior sampling typically leads to more conservative uncertainty estimates in any given case. Nevertheless, for certain classes of problems, prior sampling appears to be a promising way forward.

  18. Applying Employee Involvement in Schools.

    ERIC Educational Resources Information Center

    Mohrman, Susan Albers; And Others

    1992-01-01

    The applicability of employee-involvement approaches to the management of schools is explored, describing three approaches (parallel-suggestion involvement, job involvement, and high involvement). Design issues (technology; organizational structure; leadership; organizational boundaries, customer definition, and relation to stakeholder; measures;…

  19. Ground Water Sampling at ISCO Sites - Residual Oxidant Impact on Sample Quality and Sample Preservation Guideline

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the delivery of a chemical oxidant into the subsurface where oxidative reactions transform ground water contaminants into less toxic or harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste si...

  20. Multidrug toxicity involving sumatriptan.

    PubMed

    Knittel, Jessica L; Vorce, Shawn P; Levine, Barry; Hughes, Rhome L; Bosy, Thomas Z

    2015-01-01

    A multidrug fatality involving sumatriptan is reported. Sumatriptan is a tryptamine derivative that acts at 5-HT(1B/1D) receptors and is used for the treatment of migraines. The decedent was a 21-year-old white female found dead in bed by her spouse. No signs of physical trauma were observed and a large number of prescription medications were discovered at the scene. Toxicological analysis of the central blood revealed sumatriptan at a concentration of 1.03 mg/L. Following therapeutic dosing guidelines, sumatriptan concentrations do not exceed 0.095 mg/L. Sumatriptan was isolated by solid-phase extraction and analyzed using liquid chromatography-tandem mass spectrometry in multiple reaction monitoring mode. A tissue distribution study was completed with the following concentrations measured: 0.61 mg/L in femoral blood, 0.56 mg/L in iliac blood, 5.01 mg/L in urine, 0.51 mg/kg in liver, 3.66 mg/kg in kidney, 0.09 mg/kg in heart, 0.32 mg/kg in spleen, 0.01 mg/kg in brain, 15.99 mg/kg in lung and 78.54 mg/45 mL in the stomach contents. Carisoprodol, meprobamate, fluoxetine, doxylamine, orphenadrine, dextromethorphan and hydroxyzine were also present in the blood at the following concentrations: 3.35, 2.36, 0.63, 0.19, 0.06, 0.55 and 0.16 mg/L. The medical examiner ruled the cause of death as acute mixed drug toxicity and the manner of death as accident. PMID:25324526