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Sample records for sample problems involving

  1. Sampling problems

    NASA Technical Reports Server (NTRS)

    Flueck, J. A.; Crane, R. F.; Laughlin, C. R.; Bell, T. L.; Meiten, J. G.; Ruprecht, E.; Short, D. R.; Theon, J. S.; Vogel, J. L.

    1981-01-01

    Precipitation estimates from satellites are subject to a number of uncertainties involving design characteristics, satellite positioning, natural variability of precipitation, and the noncontinuous acquisition of data. The sources and sizes of these uncertainties are in need of proper evaluation and estimation. The present sampling and estima-theory seems to be adequate for some measurement problems (e.g., determining precipitation at a point), while others require further theoretical work (e.g., determining the time history of precipitation over large areas).

  2. 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

  3. 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.

  4. 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)

  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. Nursing students' personal experiences involving alcohol problems.

    PubMed

    Murphy-Parker, Dana; Martinez, Ruby J

    2005-06-01

    This article discusses the views and beliefs of nursing students toward people who abuse alcohol. An original study published in a separate article [Archives of Psychiatric Nursing , (2003); (4) 17 : 156-164.] examined this relationship with both a quantitative and a qualitative design. Three open-ended questions allowed for further qualitative exploration about relationships with others who have alcohol problems and beliefs about recovery. The chronic nature of alcoholism was clearly identified by students who described it as a lifelong process. Most students (79%) expressed belief that recovery was possible whether they had personal experience with people who have alcohol problems or not. The level of optimism was surprisingly high in this sample of nursing students, especially because many had had a personal experience with someone who abused alcohol. Students come to the educational setting with a clear and accurate view of the lifelong commitment that may be needed to recover from alcohol addiction, but they also come with an overly optimistic view of recovery. How this optimism impacts future care is unknown. If nursing students hold an unrealistically positive view of recovery, they may be ill prepared to handle the disappointments associated with treatment such as relapse, interpersonal conflict, health deterioration, or other related sequelae. PMID:15991149

  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. Elliptic problem involving diffuse measure data

    NASA Astrophysics Data System (ADS)

    Igbida, Noureddine; Ouaro, Stanislas; Soma, Safimba

    In this paper, we study a suitable notion of solution for which a nonlinear elliptic problem governed by a general Leray-Lions operator is well posed for any diffuse measure data. In terms of the paper (Brezis et al., 2007, [10]), we study the notion of solution for which any diffuse measure is "good measure".

  9. 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.

  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, 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...

  12. 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...

  13. 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...

  14. 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...

  15. Paleoclimate Sampling as a Sensor Placement Problem

    NASA Astrophysics Data System (ADS)

    Comboul, M.; Emile-Geay, J.; Hakim, G. J.; Evans, M. N.

    2014-12-01

    We treat paleoclimatic sampling as a sensor placement problem, attempting to find the locations where observations would optimally characterize the variability of climate fields of interest. Starting from a set of realistically-constrained, predefined potential sampling locations and observational uncertainties, we formulate optimized observing networks as the solution to a data-assimilation problem: given a stochastic representation of the Gaussian-distributed climate states of interest, which are linked to direct climate observations via a proxy system model, we may update the distribution and quantify the information gain from each possible sensor network. Furthermore, using submodular cost functions considerably reduces the size of the numerical optimization problem, as it enables iterative addition of sensors to the network. We illustrate this process with the design of an optimal network of coral ?18O used to jointly infer sea surface temperature and sea surface salinity fields. For example, given the current coral network, we show that an additional 25 to 75 observations would greatly improve the SST field reconstruction with the resampling rate being the highest in the central Pacific region. We analyze the impact of various design choices on the resulting optimal sensor network, such as the cost function formulation, the quantification of uncertainty within the proxy system model and the targeted fields. We conclude with a discussion of applications to other proxy classes.

  16. Gambling involvement and increased risk of gambling problems.

    PubMed

    Phillips, James G; Ogeil, Rowan; Chow, Yang-Wai; Blaszczynski, Alex

    2013-12-01

    The opportunity to gamble has undergone rapid expansion with technology allowing for access to gambling products 24 h a day. This increased online availability challenges governments' abilities to restrict access to gambling. Indeed, the ready access to multiple forms of gambling may potentially contribute to impaired control over urges for problem gamblers. The present study considered whether problem gamblers manifested a tendency to engage in multiple forms of gambling and identified forms of gambling which were more strongly related to problem gambling. In reanalyses of two surveys (Sample 1, N = 464, Sample 2, N = 1141), significant relationships accounting for between 11.3 and 13.5% of the variance were found between the numbers of forms of gambling accessed and degree of problem. Participation in online poker, playing cards and sports wagering were linked to problem gambling. Access to multiple forms of gambling may pose difficulties for the tracking and control of gambling. PMID:22820995

  17. 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

  18. 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…

  19. Breadth and depth involvement: Understanding Internet gambling involvement and its relationship to gambling problems.

    PubMed

    LaPlante, Debi A; Nelson, Sarah E; Gray, Heather M

    2014-06-01

    The "involvement effect" refers to the finding that controlling for gambling involvement often reduces or eliminates frequently observed game-specific associations with problem gambling. In other words, broader patterns of gambling behavior, particularly the number of types of games played over a defined period, contribute more to problem gambling than playing specific games (e.g., lottery, casino, Internet gambling). This study extends this burgeoning area of inquiry in three primary ways. First, it tests independently and simultaneously the predictive power of two gambling patterns: breadth involvement (i.e., the number of games an individual plays) and depth involvement (i.e., the number of days an individual plays). Second, it includes the first involvement analyses of actual betting activity records that are associated with clinical screening information. Third, it evaluates and compares the linearity of breadth and depth effects. We conducted analyses of the actual gambling activity of 1,440 subscribers to the bwin.party gambling service who completed an online gambling disorder screen. In all, 11 of the 16 games we examined had a significant univariate association with a positive screen for gambling disorder. However, after controlling for breadth involvement, only Live Action Internet sports betting retained a significant relationship with potential gambling-related problems. Depth involvement, though significantly related to potential problems, did not impact game-based gambling disorder associations as much as breadth involvement. Finally, breadth effects appeared steeply linear, with a slight quadratic component manifesting beyond four games played, but depth effects appeared to have a strong linear component and a slight cubic component. PMID:23915365

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

    PubMed

    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 1,040 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 tested longitudinal paths between three categories of involvement (team sports, school clubs and activities, and religious activities, measured at baseline and 15 months), problem peer associations (baseline and 15 months), and cigarette smoking behavior (baseline and 24 months). Multi-group analyses indicated pathways differed by type of activity and adolescent gender. Boys' baseline team sports and religious involvement predicted lower levels of smoking at 24 months via continued activity involvement at 15 months. Girls' involvement in school clubs and activities and religious activities indirectly predicted lower levels of smoking at 24 months via reduced exposure to problem peers at 15 months. PMID:21603061

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

    PubMed Central

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

    2010-01-01

    Longitudinal associations among different types of organized activity involvement, problem peer associations, and cigarette smoking were examined in a sample of 1,040 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 tested longitudinal paths between three categories of involvement (team sports, school clubs and activities, and religious activities, measured at baseline and 15 months), problem peer associations (baseline and 15 months), and cigarette smoking behavior (baseline and 24 months). Multi-group analyses indicated pathways differed by type of activity and adolescent gender. Boys’ baseline team sports and religious involvement predicted lower levels of smoking at 24 months via continued activity involvement at 15 months. Girls’ involvement in school clubs and activities and religious activities indirectly predicted lower levels of smoking at 24 months via reduced exposure to problem peers at 15 months. PMID:21603061

  2. 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…

  3. 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

  4. 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

  5. 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…

  6. 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.

  7. 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

  8. Adolescents previously involved in Satanism experiencing mental health problems.

    PubMed

    Heathcote, H; Gmeiner, A; Poggenpoel, M

    1999-06-01

    No research has previously been done regarding the phenomenon of adolescents who have previously been involved in Satanism and who experience obstacles in their strive for mental health. Adolescents previously involved in Satanism present behavioral problems like aggressive outbursts, depression, "psychosis" or suicide attempts, that could lead to suicide. In the phenomenon-analysis semi-structured, phenomenological interviews were performed with the respondents and their parents. The respondents were requested to write a naïve sketch about their life. After completion of the data-control, guidelines for nursing staff were set. The guidelines are set for the management of adolescents who have previously been involved in Satanism and who experience obstacles in their strive for mental health. Interviews with experts in Satanism were conducted, literature in the form of books, magazines and newspaper-clippings were used to verify the research findings. The most important guidelines are that the caregivers have to be reborn Christians; they are not allowed to show any fear or sympathy; they must have sufficient knowledge about Satanism; the adolescents have to be unconditionally accepted; the caregivers have to work in a team and the adolescents have to be taught to deal with their emotions. PMID:11040620

  9. [Adolescents previously involved in Satanism: mental health problems experience].

    PubMed

    Heathcote, H; Gmeiner, A; Poggenpoel, M

    1998-03-01

    As far as the phenomena of adolescents previously involved with satanism that experience obstacles in the strive for mental health, no research has previously been done. Adolescents previously involved in satanism, presents behaviour problems like aggressive outbursts depression, "psychosis", or suicide attempts that can even lead to suicide. In the phenomena-analysis semi-structured, phenomenological interviews with the respondents and their parents, were performed. The respondents were requested to write a naive sketch about there life. After the data-control was done, guidelines for nursing staff had been set. The guidelines are set for the management of adolescents that has previously been involved in satanism, and experiences obstacles in their strive for mental health. Interviews with experts in satanism was done, literature in the form of books, magazines and newsclippings were used to verify the findings in the research. The most important guidelines are that: the caregivers have to be reborn Christians; they are not allowed to show, any fear or sympathy; they have to have sufficient knowledge about satanism; the adolescent has to be unconditionally accepted; the caregivers have to work in a team; the adolescents have to be taught to deal with their emotions. PMID:9791342

  10. 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

  11. Avoiding Problems with Suspensions in NMR Sample Tubes

    NASA Astrophysics Data System (ADS)

    Ali, Saqib; Danish, M.; Mazhar, M.

    1995-07-01

    Many times during the sample preparation for NMR studies solid samples form suspension due to low solubility in duterated solvents. We developed a technique to get rid of this problem easily. Just tighten the lid on the NMR sample tube and seal it with parafilm. Invert the tube and centrifuge it for five minutes. Now the suspension is collected in the lid and the clear sample is ready for NMR analysis in the tube.

  12. 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.

  13. Simulating quantum correlations as a distributed sampling problem

    SciTech Connect

    Degorre, Julien; Laplante, Sophie; Roland, Jeremie

    2005-12-15

    It is known that quantum correlations exhibited by a maximally entangled qubit pair can be simulated with the help of shared randomness, supplemented with additional resources, such as communication, postselection or nonlocal boxes. For instance, in the case of projective measurements, it is possible to solve this problem with protocols using one bit of communication or making one use of a nonlocal box. We show that this problem reduces to a distributed sampling problem. We give a new method to obtain samples from a biased distribution, starting with shared random variables following a uniform distribution, and use it to build distributed sampling protocols. This approach allows us to derive, in a simpler and unified way, many existing protocols for projective measurements, and extend them to positive operator value measurements. Moreover, this approach naturally leads to a local hidden variable model for Werner states.

  14. MORSE Monte Carlo radiation transport code system. [Sample problems

    SciTech Connect

    Emmett, M.B.

    1984-07-02

    For a number of years the MORSE user community has requested additional help in setting up problems using various options. The sample problems distributed with MORSE did not fully demonstrate the capability of the code. At Oak Ridge National Laboratory the code originators had a complete set of sample problems, but funds for documenting and distributing them were never available. Recently the number of requests for listings of input data and results for running some particular option the user was trying to implement has increased to the point where it is not feasible to handle them on an individual basis. Consequently it was decided to package a set of sample problems which illustrates more adequately how to run MORSE. This write-up may be added to Part III of the MORSE report. These sample problems include a combined neutron-gamma case, a neutron only case, a gamma only case, an adjoint case, a fission case, a time-dependent fission case, the collision density case, an XCHEKR run and a PICTUR run.

  15. Variational stability of optimal control problems involving subdifferential operators

    SciTech Connect

    Tolstonogov, Aleksandr A

    2011-04-30

    This paper is concerned with the problem of minimizing an integral functional with control-nonconvex integrand over the class of solutions of a control system in a Hilbert space subject to a control constraint given by a phase-dependent multivalued map with closed nonconvex values. The integrand, the subdifferential operators, the perturbation term, the initial conditions and the control constraint all depend on a parameter. Along with this problem, the paper considers the problem of minimizing an integral functional with control-convexified integrand over the class of solutions of the original system, but now subject to a convexified control constraint. By a solution of a control system we mean a 'trajectory-control' pair. For each value of the parameter, the convexified problem is shown to have a solution, which is the limit of a minimizing sequence of the original problem, and the minimal value of the functional with the convexified integrand is a continuous function of the parameter. This property is commonly referred to as the variational stability of a minimization problem. An example of a control parabolic system with hysteresis and diffusion effects is considered. Bibliography: 24 titles.

  16. Some New Twists to Problems Involving the Gaussian Probability Integral

    NASA Technical Reports Server (NTRS)

    Simon, Marvin K.; Divsalar, Dariush

    1997-01-01

    Using an alternate form of the Gaussian probability integral discovered a number of years ago, it is shown that the solution to a number of previously considered communication problems can be simplified and in some cases made more accurate(i.e., exact rather than bounded).

  17. Enhanced multilevel linear sampling methods for inverse scattering problems

    NASA Astrophysics Data System (ADS)

    Li, Jingzhi; Liu, Hongyu; Wang, Qi

    2014-01-01

    We develop two enhanced techniques for the multilevel linear sampling method (MLSM) proposed in [32] for inverse scattering problems. Under some practical situations, the MLSM suffers certain undesirable “breakage cells” problem. We propose to avoid the curse of “breakage cells” by incorporating “expanding” and “searching” techniques. The new techniques are shown to significantly improve the robustness of the MLSM, and meanwhile they possess the same optimal computational complexity as the MLSM. Numerical experiments are presented to illustrate the promising features of the enhanced MLSMs.

  18. 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

  19. 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.

  20. 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.

  1. 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. The chemical kinetics of this reaction are poorly understood at present under the conditions of cached or curated martian samples. Among other parameters, what is the maximum temperature allowed during storage in order to preserve native martian organic compounds for analysis? What is the best means to collect headspace gases from cached martian (and other) samples? This gas will contain not only martian atmosphere but also off-gassed volatiles from the cached solids.

  2. 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.

  3. First Evidence of Comorbidity of Problem Gambling and Other Psychiatric Problems in a Representative Urban Sample of South Africa.

    PubMed

    Sharp, Carla; Dellis, Andrew; Hofmeyr, Andre; Kincaid, Harold; Ross, Don

    2015-09-01

    We investigate the extent to which problem gambling in a recent South African sample, as measured by the Problem Gambling Severity Index (PGSI), is comorbid with depression, anxiety and substance abuse. Data are from the 2010 South African National Urban Prevalence Study of Gambling Behavior. A representative sample of the urban adult population in South Africa (N = 3,000). Responses to the 9-item PGSI and ratings on the Beck Depression Index, the Beck Anxiety Inventory, and the World Health Organization Alcohol, Smoking and Substance Involvement Screening Tool (WHO ASSIST). Cross tabulations and Chi square analyses along with logistic regression analyses with and without controls for socio-demographic and/or socio-economic variables were used to identify comorbidities. The prevalence of depression, anxiety, alcohol and substance use were clearly higher among the sample at risk for problem gambling. Black African racial status and living in areas characterized by migrant mining workers was associated with increased risk of problem gambling and comorbidities. There is strong evidence that findings of comorbidities between pathological gambling and depression, anxiety and substance abuse in developed countries generalize to the developing country of South Africa. Historical context, however, gives those comorbidities a unique demographic distribution. PMID:24927870

  4. Psychosocial Correlates of Marijuana Use and Problem Drinking in a National Sample of Adolescents

    PubMed Central

    Jessor, Richard; Chase, James A.; Donovan, John E.

    1980-01-01

    Personality, environmental, and behavioral variables representing psychosocial risk factors for adolescent problem behavior were assessed in a 1974 national sample study of over 10,000 junior and senior high school students. Significant correlations were found with marijuana use, and the relationships held across differences in age, sex, and ethnic group membership. Greater involvement in marijuana use was associated with greater value on independence than on academic achievement, lower expectations for academic achievement, lesser religiosity, greater tolerance of deviance, less compatibility between friends and parents, greater influence of friends relative to parents, greater models and support for problem behavior, greater actual involvement in other problem behaviors such as drunkenness, and less involvement in conventional behavior such as attending church. Multiple regression analyses show that this pattern of psychosocial correlates accounts for over 50 per cent of the variation in marijuana use. The pattern is nearly identical to the pattern that accounts for problem drinking in these same adolescents. The similarity of the patterns of psychosocial risk, and the substantial correlations of marijuana use with problem drinking and with other problem behaviors, suggest that marijuana use is best seen as part of a syndrome of adolescent problem behavior. (Am J Public Health 70:604- 613,1980.) PMID:7377436

  5. Association between Parental Involvement in School and Child Conduct, Social, and Internalizing Problems: Teacher Report

    ERIC Educational Resources Information Center

    Kirkhaug, Bente; Drugli, May Britt; Klockner, Christian A.; Morch, Willy-Tore

    2013-01-01

    The present study examined the factor structure of the Teacher Involvement Questionnaire (Involve-T) by means of exploratory factor analysis and examined the association between children's socio-emotional and behavioural problems and teacher-reported parental involvement in school, using structural equation modelling. The study was conducted with

  6. 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-based course. This finding emphasizes the fact that appropriate scaffolding support which is commensurate with students' prior knowledge and skills must be determined via research in order to be effective.

  7. 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

  8. 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.

  9. 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…

  10. Convergence of infinite dimensional sampled LQR problems - Theory and numerical results

    NASA Technical Reports Server (NTRS)

    Rosen, I. G.; Wang, C.

    1989-01-01

    A theory is developed for the convergence of the closed-loop solution to infinite-dimensional discrete-time linear-quadratic regulator (LQR) problems on the infinite time interval to the solution of a corresponding continuous-time LQR problem as the length of the sampling interval tends toward zero. Convergence of solutions to the operator algebraic Riccati equation and corresponding optimal feedback control gains is guaranteed under appropriate uniform stabilizability and detectability conditions and consistent sampling. Also presented are numerical results involving the optimal LQ control of a heat or diffusion equation, a hereditary or delay differential equation, and a hybrid system of ordinary and partial differential equations describing the transverse vibration of a cantilevered Voigt-Kelvin viscoelastic beam with tip mass.

  11. 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.

  12. Paternal ADHD Symptoms and Child Conduct Problems: Is Father Involvement Always Beneficial?

    PubMed Central

    Romirowsky, Abigail Mintz; Chronis-Tuscano, Andrea

    2013-01-01

    Background Maternal psychopathology robustly predicts poor developmental and treatment outcomes for children with attention-deficit/hyperactivity disorder (ADHD). Despite the high heritability of ADHD, few studies have examined associations between paternal ADHD symptoms and child adjustment, and none have also considered degree of paternal involvement in childrearing. Identification of modifiable risk factors for child conduct problems is particularly important in this population given the serious adverse outcomes resulting from this comorbidity. Methods This cross-sectional study examined the extent to which paternal involvement in childrearing moderated the association between paternal ADHD symptoms and child conduct problems among 37 children with ADHD and their biological fathers. Results Neither paternal ADHD symptoms nor involvement was independently associated with child conduct problems. However, the interaction between paternal ADHD symptoms and involvement was significant, such that paternal ADHD symptoms were positively associated with child conduct problems only when fathers were highly involved in childrearing. Conclusions The presence of adult ADHD symptoms may determine whether father involvement in childrearing has a positive or detrimental influence on comorbid child conduct problems. PMID:25250402

  13. 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...

  14. Behaviour Problems across Home and Kindergarten in an Australian Sample

    ERIC Educational Resources Information Center

    Herrera, Maite; Little, Emma

    2005-01-01

    The current study examined the extent to which kindergarten children display behaviour problems in the clinical range at both home and kindergarten. Differences and similarities between parents' and teachers' responses to misbehaviour were also assessed. The co-occurrence of problems at home and kindergarten was assessed using the Preschool and

  15. 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.

  16. Problems in the sampling and analysis of carbon particulate

    NASA Astrophysics Data System (ADS)

    Cadle, Steven H.; Groblicki, Peter J.; Mulawa, Patricia A.

    Several thermal and wet chemical methods of separating organic from elemental carbon in particulate samples were examined. It is concluded that none of them represents an ideal separation procedure and that only a method-dependent operational definition of organic and elemental carbon is possible at this time. The best separation method appears to be a thermal procedure using 350C air oxidation followed by pyrolysis in He at 950C. There are also difficulties in sampling since dual filter techniques show that adsorption of organic compounds on various filter media accounted for at least 15 per cent of the total organic carbon collected during ambient sampling in Warren, MI. This adsorption further confuses the results and needs to be studied at other sampling sites.

  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. 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.…

  19. Incomplete taxon sampling is not a problem for phylogenetic inference

    PubMed Central

    Rosenberg, Michael S.; Kumar, Sudhir

    2001-01-01

    A major issue in all data collection for molecular phylogenetics is taxon sampling, which refers to the use of data from only a small representative set of species for inferring higher-level evolutionary history. Insufficient taxon sampling is often cited as a significant source of error in phylogenetic studies, and consequently, acquisition of large data sets is advocated. To test this assertion, we have conducted computer simulation studies by using natural collections of evolutionary parametersrates of evolution, species sampling, and gene lengthsdetermined from data available in genomic databases. A comparison of the true tree with trees constructed by using taxa subsamples and trees constructed by using all taxa shows that the amount of phylogenetic error per internal branch is similar; a result that holds true for the neighbor-joining, minimum evolution, maximum parsimony, and maximum likelihood methods. Furthermore, our results show that even though trees inferred by using progressively larger taxa subsamples of a real data set become increasingly similar to trees inferred by using the full sample, all inferred trees are equidistant from the true tree in terms of phylogenetic error per internal branch. Our results suggest that longer sequences, rather than extensive sampling, will better improve the accuracy of phylogenetic inference. PMID:11526218

  20. 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

  1. Biased Sampling and PCK: The Case of the Marijuana Problem

    ERIC Educational Resources Information Center

    Watson, Jane M.; Nathan, Erica L.

    2010-01-01

    As part of an interview protocol investigating teachers' pedagogical content knowledge (PCK) in statistics, 40 teachers were presented with a newspaper article reporting a phone-in survey about the legalisation of marijuana. The article and a question about the reliability of the sample had earlier been used in student surveys, and three student

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

    ERIC Educational Resources Information Center

    Ybrandt, Helene

    2010-01-01

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

  3. Personifying self in physics problem situations involving forces as a student help strategy

    NASA Astrophysics Data System (ADS)

    Tabor-Morris, A. E.

    2013-03-01

    How can physics teachers best guide students regarding physics problem situations involving forces? A suggestion is made here to personify oneself as the object in question, that is, to pretend to be the object undergoing forces and then qualify and quantify those forces according to their vectors for the system at hand. This personification is not meant to empower the object to act, just to sense the forces it is experiencing. This strategy may be especially useful to beginning physics learners attacking problems that involve both multiple forces AND multiple objects, since each object acted upon needs to be considered separately, using the idea that one cannot be two places at once. An example of this type of problem expounded on here is Atwood's machine: two weights hung over a pulley with a single rope. Another example given is electromagnetic forces on one charge caused by other charges in the vicinity. Discussion is made on implementation of classroom strategies. Department of Physics

  4. Logistic analysis of epidemiologic studies with augmentation sampling involving re-stratification and population expansion

    PubMed Central

    Li, Yan; Safaeian, Mahboobeh; Robbins, Hilary A.; Graubard, Barry I.

    2015-01-01

    Epidemiologic cross-sectional, case-cohort, or casecontrol studies often select augmentation samples to supplement an existing (baseline) sample, primarily for the two reasons: (1) to increase the sample sizes from certain subdomains of interest that were not originally considered in the design of the baseline study and (2) to obtain samples from an extension of the target population. To address these two objectives, two-stage stratified sample designs are considered, where the stratification based on the expanded population at the second stage is not nested in the first stage strata. The sample weighting and Taylor linearization variance estimation for the two-stage stratified sample designs, involving re-stratification and population expansion, are provided for estimating population totals and logistic regression coefficients. Results from limited simulation studies and a logistic regression analysis of a study of human papillomavirus serology are provided. PMID:24907707

  5. 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.

  6. 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

  7. 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 of multiple perspectives. In general, less comprehensive ways of experiencing the phenomenon include seeking information to make the problem more well-structured and thereby allowing the completion of a classroom task. Movement towards more comprehensive ways of experiencing include accepting ambiguity as inherent to the problem, and utilizing multiple perceptions to develop a design solution. The most comprehensive ways of experiencing included experiences that embraced ambiguity as an integral part of the problem solving process and internalized multiple perspectives through working with and learning from others. The resulting outcome space is of practical use to engineering educators who wish to create more inclusive and effective cornerstone design learning environments. The findings demonstrate that significant variation is present in the way that a small group of first-year engineering students from a single university experience engaging with problems that involve multiple possible solutions. Powerful ways of experiencing this crucial aspect of engineering education include appreciation of the multiple ways of perceiving an ill-structured problem as well as an ability to accept the ambiguity that is associated with engaging with these types of problems. While some students are capable of such an experience, others do seek a single correct answer through an attempt to eliminate ambiguity. Knowing these key axes of variation informs educators' ability to accommodate a range of ways of experiencing design tasks and to design learning environments that foster development in these identified aspects of the experience to promote more meaningful learning experiences.

  8. Laboratory detective work identifies a mishandling problem in sample aliquoting.

    PubMed

    Zhu, Claire; Pinsky, Paul; Huang, Wen-Yi; Purdue, Mark

    2014-12-01

    Data from a recent ovarian cancer biomarker study using serum aliquots from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial Biorepository showed that CA125II concentrations in these aliquots were significantly lower than those previously measured in the same subjects from the same blood draw. We designed an experiment to investigate whether samples used in the study (reference study) were compromised during the aliquoting process. We measured CA125II in the "sister" vials created during the same aliquoting process as the reference study aliquot, and in "cousin" vials newly aliquoted from another parent vial from the same blood draw, from 15 healthy controls in the study. Because the sister vials were created in a specific order, we also assessed whether there was a CA125II concentration gradient among the sisters. The Wilcoxon signed-rank test was used to test the statistical significance of the observed differences. Mean CA125II concentration (volume-averaged) was greater in the sisters than the cousins in all 15 subjects (p<0.001). The mean coefficient of variation was 0.25 (range: 0.12-0.43) in the sisters and 0.11 (range: 0.-1.1) in the cousins (p<0.008). The mean ratio of CA125II in the 5(th) aliquoted versus the 3(rd) aliquoted sister vial was 1.66 (1.25-2.5, p<0.001). These data suggest that the parent vials were not adequately mixed before they were aliquoted. CA125II in serum can partially precipitate to form a concentration gradient in long-term storage. Rigorous vortexing after thawing and before aliquoting is thus critical. PMID:25496156

  9. 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.

  10. The impact of gambling advertising: Problem gamblers report stronger impacts on involvement, knowledge, and awareness than recreational gamblers.

    PubMed

    Hanss, Daniel; Mentzoni, Rune A; Griffiths, Mark D; Pallesen, Stle

    2015-06-01

    Although there is a general lack of empirical evidence that advertising influences gambling participation, the regulation of gambling advertising is hotly debated among academic researchers, treatment specialists, lobby groups, regulators, and policymakers. This study contributes to the ongoing debate by investigating perceived impacts of gambling advertising in a sample of gamblers drawn from the general population in Norway (n = 6,034). Three dimensions of advertising impacts were identified, representing perceived impacts on (a) gambling-related attitudes, interest, and behavior ("involvement"); (b) knowledge about gambling options and providers ("knowledge"); and (c) the degree to which people are aware of gambling advertising ("awareness"). Overall, impacts were strongest for the knowledge dimension, and, for all 3 dimensions, the impact increased with level of advertising exposure. Those identified as problem gamblers in the sample (n = 57) reported advertising impacts concerning involvement more than recreational gamblers, and this finding was not attributable to differences in advertising exposure. Additionally, younger gamblers reported stronger impacts on involvement and knowledge but were less likely to agree that they were aware of gambling advertising than older gamblers. Male gamblers were more likely than female gamblers to report stronger impacts on both involvement and knowledge. These findings are discussed with regard to existing research on gambling advertising as well as their implications for future research and policy-making. (PsycINFO Database Record PMID:25730628

  11. 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

  12. 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

  13. 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.

  14. 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

  15. Short-term trajectories of substance use in a sample of drug-involved probationers.

    PubMed

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

    2014-02-01

    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

  16. Involvement in Child Rearing and Firm Control Parenting by Male Cohabiting Partners in Black Low-Income Stepfamilies: Forecasting Adolescent Problem Behaviors.

    PubMed

    Forehand, Rex; Parent, Justin; Golub, Andrew; Reid, Megan; Lafko, Nicole

    2015-09-01

    Cohabitation is a family structure that is rapidly increasing in the United States. The current longitudinal study examined the interplay of involvement in a youth's daily activities and firm control parenting by male cohabiting partners (MCPs) on change in adolescents' internalizing and externalizing problems. In a sample of 111 inner-city African American families, adolescents reported on involvement and parenting by MCPs at Wave 1 and biological mothers reported on adolescent problem behaviors at Waves 1 and 2. A significant interaction indicated that low involvement and low firm control by MCPs at Wave 1 were associated with the highest level of internalizing problems at Wave 2. An interaction did not emerge when externalizing problems served as the outcome. The findings indicate that male partners play an important role in parenting adolescents in cohabiting families and should be considered potential participants in prevention and intervention programs. PMID:26007695

  17. 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

  18. 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.

  19. 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.…

  20. 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

  1. 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

  2. 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.

  3. Does psychological strengths and subjective well-being predicting parental involvement and problem solving among Malaysian and Indian students?

    PubMed

    Khan, Aqeel; Ahmad, Roslee; Hamdan, Abdul Rahim; Mustaffa, Mohamed Sharif; Tahir, Lokman Mohd

    2014-01-01

    The present study examined the predictors of psychological strengths and subjective well-being for dealing with academic stress perceived by university engineering students. Sample of 400 Malaysian (N = 180 boys and N = 220 girls) age varies 18 to 25 years and 400 Indian students (N = 240 boys and N = 160 girls) age varies 18 to 25 years from public universities were participated. Quantitative method was used for data analysis. Findings shows that gender, religiosity and socioeconomic status are significantly influencing psychological strengths and subjective well-being of both Indian and Malaysian students. Findings also revealed that parental involvement and problem solving coping styles were significantly predicting psychological strengths and subjective well-being among both countries participants. Findings of the current study provide the insight for the educators, and parents dealing with adolescents. PMID:25674482

  4. 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.

  5. 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.

  6. 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

  7. Propionibacterium acnes populations involved in deep pathological samples and their dynamics along the cardiac surgical pathway.

    PubMed

    Romano-Bertrand, S; Beretta, M; Jean-Pierre, H; Frapier, J-M; Calvet, B; Parer, S; Jumas-Bilak, E

    2015-02-01

    Propionibacterium acnes belongs to the normal skin microbiota, but it is also responsible for acne vulgaris and causes serious infections such as endocarditis and surgical site infections (SSI). The P. acnes population is structured into phylogenetic groups, with phylotype I being associated with acne. Herein, we explore the link between phylotypes and clinical origins in a collection of P. acnes isolated from different body sites, involved in deep infections or healthcare-associated infections (HAI), with particular emphasis on strains from cardiac SSI. Cardiac SSI have been further studied in terms of P. acnes population dynamics during the care pathway. The recA and tly genes phylotypes were compared to hemolytic behavior, susceptibility to antimicrobial agents, and clinical origins. An original approach of recA polymerase chain reaction temporal temperature gel electrophoresis (PCR-TTGE) was developed and applied for the direct identification of P. acnes phylotypes in surgical samples, in order to assess their temporal dynamics during the surgical course. Our results underlined the preferential involvement of IA-2/IB and II phylogroups in HAI and SSI. Unlike IA and II, type IA-2/IB presented a gradual increase with the depth of sampling in the peroperative phase of cardiac surgery. Phylotypes IA and IA-2/IB were both predominant in scar tissues and on postoperative skin, suggesting a specific predisposition to recolonize skin. Particular association of the phylotype IA-2/IB with SSI and its propensity to colonize wounds in cardiac surgery was observed. We assumed that the follow-up of P. acnes phylotypes during pathological processes could give new clues for P. acnes pathogenicity. PMID:25169966

  8. Alcohol-Focused Spouse Involvement and Behavioral Couples Therapy: Evaluation of Enhancements to Drinking Reduction Treatment for Male Problem Drinkers

    ERIC Educational Resources Information Center

    Walitzer, Kimberly S.; Dermen, Kurt H.

    2004-01-01

    This study evaluated the effects of alcohol-focused spouse involvement and behavioral couples therapy (BCT) in group drinking reduction treatment for male problem drinkers. Sixty-four male clients and their female partners were randomly assigned to 1 of 3 conditions: treatment for problem drinkers only (PDO), couples alcohol-focused treatment, or

  9. 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…

  10. 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

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

    NASA Astrophysics Data System (ADS)

    Ramos, Miguel; Tavares, Hugo; Terracini, Susanna

    2015-10-01

    Let {? 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({?_{k1}(?_1),ldots,?_{k_m}(?_m)): (?_1,ldots, ?_m) in {P}_m(?)}, where {?_{k_i}(?_i)} denotes the k i -th eigenvalue of {(-?,H10(?_i))} counting multiplicities, and {P}_m(?)} is the set of all open partitions of {?} , namely {P}_m(?)={(?_1, ldots, ?_m):?_i subset ? open, ?i \\cap?_j=emptyset forall i ? j }. While the existence of a quasi-open optimal partition {(?_1,ldots, ?_m)} follows from a general result by uc(Bucur), uc(Buttazzo) and uc(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 ?i \\cap ?} is, up to a residual set, locally a {C^{1,?} hypersurface. This last result extends the ones in the paper by uc(Caffarelli) and uc(Lin) [J Sci Comput 31(1-2):5-18, 2007] to the case of higher eigenvalues.

  12. Efficient Gaussian Sampling for Solving Large-Scale Inverse Problems Using MCMC

    NASA Astrophysics Data System (ADS)

    Gilavert, Clement; Moussaoui, Said; Idier, Jerome

    2015-01-01

    The resolution of many large-scale inverse problems using MCMC methods requires a step of drawing samples from a high dimensional Gaussian distribution. While direct Gaussian sampling techniques, such as those based on Cholesky factorization, induce an excessive numerical complexity and memory requirement, sequential coordinate sampling methods present a low rate of convergence. Based on the reversible jump Markov chain framework, this paper proposes an efficient Gaussian sampling algorithm having a reduced computation cost and memory usage. The main feature of the algorithm is to perform an approximate resolution of a linear system with a truncation level adjusted using a self-tuning adaptive scheme allowing to achieve the minimal computation cost. The connection between this algorithm and some existing strategies is discussed and its efficiency is illustrated on a linear inverse problem of image resolution enhancement.

  13. Factors related to sexual abuse and forced sex in a sample of women experiencing police-involved intimate partner violence.

    PubMed

    Messing, Jill Theresa; Thaller, Jonel; Bagwell, Meredith

    2014-08-01

    Intimate partner sexual violence (IPSV) is a significant social problem, particularly among women who are concurrently experiencing physical violence in their intimate relationships. This research examined the prevalence and factors associated with IPSV among a sample of women recruited at the scene of police-involved intimate partner violence incidents (N = 432). Within this sample, 43.98 percent of participants reported experiencing IPSV; this includes 17.36 percent who reported sexual abuse and 26.62 percent who reported forced sex. Multinomial logistic regression was used to examine the factors related to sexual abuse and forced sex, controlling for victim and relationship characteristics. Compared with women not reporting IPSV, women who were sexually abused or forced into sexual intercourse were significantly more likely to experience strangulation, feelings of shame, and posttraumatic stress disorder symptoms. Women whose partners had forced sex were more likely to report that they had a child in common with their abusive partner; and that their partner was sexually jealous, had threatened to kill them, had stalked or harassed them, or caused them to have a miscarriage due to abuse. These findings can be used to better inform social work practitioners about the prevalence and nature of IPSV and the associated risk factors, and can assist in routine screening and intervention. PMID:25095631

  14. 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…

  15. Factors, Correlates, Problem Areas Affecting Career Decision Making of a Cross-Sectional Sample of Students.

    ERIC Educational Resources Information Center

    O'Neil, James M.; And Others

    A study was conducted to investigate the effects of the correlates and problem areas affecting career decision making and specifically to test the validity of the O'Neil, Meeker & Borgers' (1978) model. A cross-sectional sample of high school, undergraduate, and graduate students (N=1,436) responded to the Career Factor Checklist (CFC) and

  16. 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

  17. 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 {&ucedil;p_{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.

  18. Prevalence and Correlates of Problem Gambling in a Representative Sample of Norwegian 17-Year-Olds.

    PubMed

    Hanss, Daniel; Mentzoni, Rune A; Blaszczynski, Alex; Molde, Helge; Torsheim, Torbjrn; Pallesen, Stle

    2015-09-01

    We report data collected in a representative sample of 17-year-old Norwegians to investigate prevalence rates of non-problem, risk, and problem gambling, as measured by the Problem Gambling Severity Index (PGSI). In addition, we explored the importance of demographic, personality, motivational, social, and health variables explaining variance in adolescent gambling. Prevalence rates of risk and problem gambling were low but similar to those found in previous studies outside of Norway using the PGSI in adolescent samples. With regard to the relative importance of the various covariates, we found that motivational variables (future gambling intentions, attitudes toward gambling, and gambling-related knowledge) distinguished best between those who did not gamble, non-problem gamblers, and risk and problem gamblers. Furthermore, social variables were important covariates of adolescent gambling; significant associations were found for family and friends' approval of gambling, parental monitoring, father's level of education, and having relatives or friends with a history of a gambling disorder. We discuss possible reasons for differences between the covariates with regard to their importance for explaining adolescent gambling and address implications for future research. PMID:24619792

  19. An algorithm for the weighting matrices in the sampled-data optimal linear regulator problem

    NASA Technical Reports Server (NTRS)

    Armstrong, E. S.; Caglayan, A. K.

    1976-01-01

    The sampled-data optimal linear regulator problem provides a means whereby a control designer can use an understanding of continuous optimal regulator design to produce a digital state variable feedback control law which satisfies continuous system performance specifications. A basic difficulty in applying the sampled-data regulator theory is the requirement that certain digital performance index weighting matrices, expressed as complicated functions of system matrices, be computed. Infinite series representations are presented for the weighting matrices of the time-invariant version of the optimal linear sampled-data regulator problem. Error bounds are given for estimating the effect of truncating the series expressions after a finite number of terms, and a method is described for their computer implementation. A numerical example is given to illustrate the results.

  20. Gang Problems and Gang Programs in a National Sample of Schools.

    ERIC Educational Resources Information Center

    Gottfredson, Gary D.; Gottfredson, Denise C.

    This report describes approaches used by schools to prevent or reduce gang involvement among schools. The study of gang prevention and intervention builds on a large-scale National Study of Delinquency Prevention in Schools. A sample of 1,279 schools participated in the study. Overall, 7.6% of the male and 3.8% of the female secondary students

  1. Identifying indicators of harmful and problem gambling in a Canadian sample through receiver operating characteristic analysis.

    PubMed

    Quilty, Lena C; Avila Murati, Daniela; Bagby, R Michael

    2014-03-01

    Many gamblers would prefer to reduce gambling on their own rather than to adopt an abstinence approach within the context of a gambling treatment program. Yet responsible gambling guidelines lack quantifiable markers to guide gamblers in wagering safely. To address these issues, the current investigation implemented receiver operating characteristic (ROC) analysis to identify behavioral indicators of harmful and problem gambling. Gambling involvement was assessed in 503 participants (275 psychiatric outpatients and 228 community gamblers) with the Canadian Problem Gambling Index. Overall gambling frequency, duration, and expenditure were able to distinguish harmful and problematic gambling at a moderate level. Indicators of harmful gambling were generated for engagement in specific gambling activities: frequency of tickets and casino; duration of bingo, casino, and investments; and expenditures on bingo, casino, sports betting, games of skill, and investments. Indicators of problem gambling were similarly produced for frequency of tickets and casino, and expenditures on bingo, casino, games of skill, and investments. Logistic regression analyses revealed that overall gambling frequency uniquely predicted the presence of harmful and problem gambling. Furthermore, frequency indicators for tickets and casino uniquely predicted the presence of both harmful and problem gambling. Together, these findings contribute to the development of an empirically based method enabling the minimization of harmful or problem gambling through self-control rather than abstinence. PMID:23647158

  2. An experience sampling study of PTSD and alcohol-related problems.

    PubMed

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

    2014-12-01

    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 8 brief questionnaires daily for 2 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

  3. 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 17.5yr, range 9.8-23.5yr) 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 0.94mg/dL (normal value 0.20-1.90mg/dL), with a mean level 0.560.36mg/dL and a median level 0.6mg/dL. Among these patients, signs and symptoms of mucositis failed to respond to standard chronic GVHD therapy. After receiving treatment with 2000mg 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

  4. 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…

  5. 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

  6. The association between childhood maltreatment, mental health problems, and aggression in justice-involved boys.

    PubMed

    Hoeve, Machteld; Colins, Olivier F; Mulder, Eva A; Loeber, Rolf; Stams, Geert Jan J M; Vermeiren, Robert R J M

    2015-09-01

    The link between childhood maltreatment and adolescent aggression is well documented; yet, studies examining potential mechanisms that explain this association are limited. In the present study, we tested the association between childhood maltreatment and adolescent aggression in boys in juvenile justice facilities (N?=?767) and examined the contribution of mental health problems to this relationship. Data on childhood maltreatment, mental health problems, and aggression were collected by means of self-report measures and structural equation models were used to test mediation models. We found that mental health problems mediated the link between maltreatment and aggression. Results demonstrated different pathways depending on the type of aggression examined. The association between childhood maltreatment and reactive aggression was fully mediated by a variety of mental health problems and for proactive aggression the association was partially mediated by mental health problems. We also found that reactive and proactive aggression partially mediated the association between maltreatment and mental health problems. These findings suggest that a transactional model may best explain the negative effects of childhood trauma on mental health problems and (in particular reactive) aggression. In addition, our findings add to the existing evidence that reactive and proactive aggression have different etiological pathways. Aggr. Behav. 41:488-501, 2015. 2015 Wiley Periodicals, Inc. PMID:25788428

  7. 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 by rate constants. These problems are isomorphic with chemical kinetics problems. Recently, several efficient techniques for this purpose have been developed based on the approach originally proposed by Gillespie. Although the utility of the techniques mentioned above for Bayesian problems has not been determined, further research along these lines is warranted

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

    PubMed

    Kleibeuker, Sietske W; Koolschijn, P Cdric 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

  9. 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.

  10. Personal values and involvement in problem behaviors among Bahamian early adolescents: a cross-sectional study

    PubMed Central

    Liu, Hongjie; Yu, Shuli; Cottrell, Lesley; Lunn, Sonja; Deveaux, Lynette; Brathwaite, Nanika V; Marshall, Sharon; Li, Xiaoming; Stanton, Bonita

    2007-01-01

    Background Few studies, particularly in developing countries, have explored the relationship between adolescents and parental values with adolescent problem behaviors. The objectives of the study are to (1) describe adolescents' personal values, their problem behaviors, and the relationships thereof according to gender and (2) examine the relationship between parental values, adolescent values, and adolescents' problem behaviors among sixth-grade students and one of their parents. Methods The data used in these analyses were from the baseline assessment of a school-based HIV risk reduction intervention being conducted and evaluated among sixth grade students and one of their parents across 9 elementary schools in The Bahamas. Personal values were measured by the Portrait Values Questionnaire (PVQ). Seven reported problem behaviors were queried from the students, which included physical fight with a friend, drank alcohol, beer, or wine, smoked a cigarette, pushed or carried any drugs, carried a gun, knife, screwdriver or cutlass to use as a weapon, had sex and used marijuana or other illicit drugs over the past 6 months. Multilevel modeling for binary data was performed to estimate the associations between adolescent and parental values and adolescent problem behaviors. Results Among 785 students, 47% of the students reported at least one problem behavior. More boys (54%) reported having one or more problem behaviors than girls (41%, p < 0.01). Boys compared to girls expressed a higher level of self-enhancement (means score: 36.5 vs. 35.1; p = 0.03), while girls expressed a higher level of self-transcendence (42.3 vs. 40.7; p = 0.03). The results of multilevel modeling indicates that boys with a higher level of self-enhancement and girls with a higher level of openness to change and a lower level of conservation were more likely to report engagement in problem behaviors. Only two parental values (self-transcendence and conservation) were low or modestly correlated with youth' values (openness to change and self-enhancement). Parental-reported values documented limited association on adolescents' reported values and behaviors. Conclusion In designing interventions for reducing adolescents' problem behaviors, it may be important to understand the values associated with specific problem behaviors. Further exploration regarding lack of association between adolescent and parental values and problem behaviors is needed. PMID:17605792

  11. Working conditions, adverse events and mental health problems in a sample of 949 German teachers.

    TOXLINE Toxicology Bibliographic Information

    Bauer J; Unterbrink T; Hack A; Pfeifer R; Buhl-Griesshaber V; Müller U; Wesche H; Frommhold M; Seibt R; Scheuch K; Wirsching M

    2007-04-01

    OBJECTIVES: The aim of this study was (1) to explore in detail the working load of teachers, (2) to analyse the extent of negative or threatening school-related events teachers are confronted with, and (3) to evaluate mental health strain by applying the general health questionnaire (GHQ).METHODS: A sample of 949 teachers in 10 grammar schools (German: Gymnasien) and 79 secondary modern schools (German: Hauptschulen) was investigated applying (1) a questionnaire covering different aspects of the occupational burden and threatening school-associated events and (2) the general health questionnaire (GHQ-12).RESULTS: Based on what teachers indicated in the questionnaire, full-time teachers work more than 51 h weekly. More than 42% of our sample indicated verbal insults, almost 7% deliberate damage of personal belongings, and 4.4% threat of violence by pupils during the past 12 months. When applying the GHQ-12, we found that 29.8% of the sample report significant mental health problems. With respect to school types, teachers in secondary modern schools indicated more of such problems, while no effects regarding age, gender, or full/part-time teaching were observed.CONCLUSIONS: To be a teacher is a hard work and requires coping of considerable amount of adverse events. Based on the GHQ, nearly 30% of teachers suffer from significant mental health problems.

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

    USGS Publications Warehouse

    Horowitz, A.J.

    1997-01-01

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

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

    PubMed

    Carrillo, José Antonio; Vázquez, Juan Luis

    2015-09-13

    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

  14. 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

  15. 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

  16. "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…

  17. Family physicians' involvement and self-reported comfort and skill in care of children with behavioral and emotional problems: a population-based survey

    PubMed Central

    Miller, Anton R; Johnston, Charlotte; Klassen, Anne F; Fine, Stuart; Papsdorf, Michael

    2005-01-01

    Background Little is known about general and family practitioners' (GP/FPs') involvement and confidence in dealing with children with common psychosocial problems and mental health conditions. The aims of this study were to ascertain GP/FPs' preferred level of involvement with, and perceived comfort and skill in dealing with children with behavioral problems, social-emotional difficulties, attention-deficit/hyperactivity disorder (ADHD), and mood disorders; and to identify factors associated with GP/FPs' involvement, comfort and skill. Methods Postal survey of a representative sample of 801 GP/FPs in British Columbia, Canada, which enquired about level of involvement (from primarily refer out to deal with case oneself); ratings of comfort/skill with assessment/diagnosis and management; beliefs regarding psychosocial problems in children; basic demographics; and practice information. Results Surveys were completed by 405 of 629 eligible GP/FPs (64.4%). Over 80% of respondents reported collaborative arrangements with specialists across problem and condition types, although for children with behavior problems or ADHD, more physicians primarily refer (?2 (1) = 9.0; P < 0.005; and ?2 (1) = 103.9; P < 0.001, respectively). Comfort/skill levels (mean s.d) were higher for mood disorders (4.4 1.3) than behavior problems (3.6 1.1; F [3, 1155] = 84.0, P < .0001; effect size = 0.67), but not different from social-emotional difficulties (3.8 1.1) or ADHD (3.9 1.3). Taking primary responsibility for a case was consistently related to self-reported comfort/skill with each condition type (34% to 61% of variance across condition types), while comfort/skill ratings for each condition were related to exposure to relevant continuing medical education (all P ? 0.001), and beliefs that these problems are significant and that GP/FPs have a role to play in dealing with them (P values ranged from 0.01 to <0.001). Conclusion Supporting GP/FPs in their care for children with common psychosocial and mental health problems should include efforts to bolster their confidence and modify attitudes in relation towards these problems, especially behavior problems and ADHD, possibly within innovative continuing education programs. PMID:15762982

  18. 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 2144 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 condition that is costly to treat and has long-term implications for drug users and services caring for current or former injectors long after illicit drug use has ceased. PMID:25119472

  19. 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…

  20. High-Order Integral Equation Methods for Diffraction Problems Involving Screens and Apertures

    NASA Astrophysics Data System (ADS)

    Lintner, Stephane K.

    This thesis presents a novel approach for the numerical solution of problems of diffraction by infinitely thin screens and apertures. The new methodology relies on combination of weighted versions of the classical operators associated with the Dirichlet and Neumann open-surface problems. In the two-dimensional case, a rigorous proof is presented, establishing that the new weighted formulations give rise to second-kind Fredholm integral equations, thus providing a generalization to open surfaces of the classical closed-surface Calderon formulae. High-order quadrature rules are introduced for the new weighted operators, both in the two-dimensional case as well as the scalar three-dimensional case. Used in conjunction with Krylov subspace iterative methods, these rules give rise to efficient and accurate numerical solvers which produce highly accurate solutions in small numbers of iterations, and whose performance is comparable to that arising from efficient high-order integral solvers recently introduced for closed-surface problems. Numerical results are presented for a wide range of frequencies and a variety of geometries in two- and three-dimensional space, including complex resonating structures as well as, for the first time, accurate numerical solutions of classical diffraction problems considered by the 19th-century pioneers: diffraction of high-frequency waves by the infinitely thin disc, the circular aperture, and the two-hole geometry inherent in Young's experiment.

  1. 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

  2. The Assessment of Children with Learning Problems: A Planning Process Involving the Teacher.

    ERIC Educational Resources Information Center

    Ozer, Mark N.

    1978-01-01

    The role of the special resource teacher can be seen as that of a consultant to the classroom teacher in increasing the teacher's awareness of his or her own problem-solving experiences with the learning disabled child. (Author/PHR)

  3. Interval-valued optimization problems involving (?, ?)-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

  4. Interval-Valued Optimization Problems Involving (?, ?)-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

  5. 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 surface of a M-dimensional, unit radius hyper-sphere, (ii) relocating the N points on a representative set of N hyper-spheres of different radii, and (iii) transforming the coordinates of those points to lie on N different hyper-ellipsoids spanning the multivariate Gaussian distribution. The above method is applied in a dimensionality reduction context by defining flow-controlling points over which representative sampling of hydraulic conductivity is performed, thus also accounting for the sensitivity of the flow and transport model to the input hydraulic conductivity field. The performance of the various stratified sampling methods, LH, SL, and ME, is compared to that of SR sampling in terms of reproduction of ensemble statistics of hydraulic conductivity and solute concentration for different sample sizes N (numbers of realizations). The results indicate that ME sampling constitutes an equally if not more efficient simulation method than LH and SL sampling, as it can reproduce to a similar extent statistics of the conductivity and concentration fields, yet with smaller sampling variability than SR sampling. References [1] Gutjahr A.L. and Bras R.L. Spatial variability in subsurface flow and transport: A review. Reliability Engineering & System Safety, 42, 293-316, (1993). [2] Helton J.C. and Davis F.J. Latin hypercube sampling and the propagation of uncertainty in analyses of complex systems. Reliability Engineering & System Safety, 81, 23-69, (2003). [3] Switzer P. Multiple simulation of spatial fields. In: Heuvelink G, Lemmens M (eds) Proceedings of the 4th International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental Sciences, Coronet Books Inc., pp 629?635 (2000).

  6. Setting Structute, Involvement, and Developmental Status as Learner: Elements of the Problem of the Match.

    ERIC Educational Resources Information Center

    Grannis, Joseph C.; And Others

    In order to study the appropriateness of different structured classroom settings for children's learning and development, the Columbia Classroom has constructed IRIS (Involvement Ratings in Settings) and PRIN (the Pupil Role Interview). IRIS, a seven dimensional scale of affectivity by non-verbal indices, has been employed in two classrooms for…

  7. [Problems in sampling the polycyclic aromatic hydrocarbons and air-dispersed particles].

    PubMed

    Pozzoli, L; Cottica, D

    1984-01-01

    Polynuclear aromatic hydrocarbons (PAH) are difficult to monitor and quantify. This study has been worked-out to evaluate various sampling methods for monitoring PAH in the work environment: the sampling devices were tested on the field in a carbon electrodes factory. During the field surveys we used the following sampling procedures that actually are the most adopted: Glass fiber filter, Silver membrane (Teflon, cellulosic esters), The over mentioned membrane filters followed by solid substrate (Amberlite XAD-2). For the analytical quantification we followed this procedure: PAH s extraction from membranes and resins by solvent in ultrasonic bath; quantification by GS-MS (single ion monitor, capillary column, on column injection). Results of field testing show that for completely retain PAHs during air sampling in work environment it is necessary to use a membrane filter followed by a back-up tube of Amberlite-XAD-2 resin: the use of this sampling device is particularly recommended during monitoring of work operations with temperature greater than or equal to 150 degrees C involving coke oven procedure, charcoal production, asphalt production, petroleum coking operations. PMID:6545210

  8. Entropy and information in neural spike trains: Progress on the sampling problem

    NASA Astrophysics Data System (ADS)

    Nemenman, Ilya; Bialek, William; de Ruyter van Steveninck, Rob

    2004-05-01

    The major problem in information theoretic analysis of neural responses and other biological data is the reliable estimation of entropy-like quantities from small samples. We apply a recently introduced Bayesian entropy estimator to synthetic data inspired by experiments, and to real experimental spike trains. The estimator performs admirably even very deep in the undersampled regime, where other techniques fail. This opens new possibilities for the information theoretic analysis of experiments, and may be of general interest as an example of learning from limited data.

  9. A new approach to the solution of boundary value problems involving complex configurations

    NASA Technical Reports Server (NTRS)

    Rubbert, P. E.; Bussoletti, J. E.; Johnson, F. T.; Sidwell, K. W.; Rowe, W. S.; Samant, S. S.; Sengupta, G.; Weatherill, W. H.; Burkhart, R. H.; Woo, A. C.

    1986-01-01

    A new approach for solving certain types of boundary value problems about complex configurations is presented. Numerical algorithms from such diverse fields as finite elements, preconditioned Krylov subspace methods, discrete Fourier analysis, and integral equations are combined to take advantage of the memory, speed and architecture of current and emerging supercomputers. Although the approach has application to many branches of computational physics, the present effort is concentrated in areas of Computational Fluid Dynamics (CFD) such as steady nonlinear aerodynamics, time harmonic unsteady aerodynamics, and aeroacoustics. The most significant attribute of the approach is that it can handle truly arbitrary boundary geometries and eliminates the difficult task of generating surface fitted grids.

  10. Helmholtz Fermi surface harmonics: an efficient approach for treating anisotropic problems involving Fermi surface integrals

    NASA Astrophysics Data System (ADS)

    Eiguren, Asier; Gurtubay, Idoia G.

    2015-03-01

    We present a new efficient numerical approach for representing an-isotropic physical quantities and/or matrix elements defined on the Fermi surface (FS) of metallic materials. The method introduces a set of numerically calculated generalized orthonormal functions, which are the solutions of the Helmholtz equation defined on the FS, where the periodicity of the reciprocal space is treated as a boundary condition. In essence, what we introduce is a generalization of the Spherical Harmonics for any periodic Fermi Surface and regardless of its topology. The main motivation of the approach is to handle an-isotropic many-body problems very efficiently. In this context we demonstrate how our theory reduces, by several orders of magnitude, the computational effort when applied to several well know many-body theoretical models such as the electron-phonon. Moreover, the method is demonstrated to be very robust in handling problems with any crystal structure or topology of the FS. We illustrate the method showing applications on several relevant surface and bulk systems.

  11. 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

  12. Genomic influences on alcohol problems in a population-based sample of young adults

    PubMed Central

    Edwards, Alexis C.; Aliev, Fazil; Wolen, Aaron R.; Salvatore, Jessica E.; Gardner, Charles O.; McMahon, George; Evans, David M.; Macleod, John; Hickman, Matt; Dick, Danielle M.; Kendler, Kenneth S.

    2014-01-01

    Aims Alcohol problems (AP) contribute substantially to the global disease burden. Twin and family studies suggest that AP are genetically influenced, though few studies have identified variants or genes that are robustly associated with risk. This study identifies genetic and genomic influences on AP during young adulthood, which is often when drinking habits are established. Design We conducted a genome-wide association study of AP. We further conducted gene-based tests, gene ontology analyses, and functional genomic enrichment analyses to assess genomic factors beyond single variants that are relevant to AP. Setting The Avon Longitudinal Study of Parents and Children, a large population-based study of a UK birth cohort. Participants Genetic and phenotypic data were available for 4304 participants. Measurements The AP phenotype was a factor score derived from items from the Alcohol Use Disorders Identification Test, symptoms of DSM-IV alcohol dependence, and three additional problem-related items. Findings One variant met genome-wide significance criteria. Four out of 22,880 genes subjected to gene-based analyses survived a stringent significance threshold (q< .05); none of these have been previously implicated in alcohol-related phenotypes. Several biologically plausible gene ontologies were statistically over-represented among implicated SNPs. SNPs on the Illumina 550K SNP chip accounted for ~5% of the phenotypic variance in AP. Conclusions Genetic and genomic factors appear to play a role in alcohol problems in young adults. Genes involved in nervous system-related processes, such as signal transduction and neurogenesis, potentially contribute to liability to alcohol problems, as do genes expressed in non-brain tissues. PMID:25439982

  13. Movie Exposure to Alcohol Cues and Adolescent Alcohol Problems: A Longitudinal Analysis in a National Sample

    PubMed Central

    Wills, Thomas A.; Sargent, James D.; Gibbons, Frederick X.; Gerrard, Meg; Stoolmiller, Mike

    2009-01-01

    The authors tested a theoretical model of how exposure to alcohol cues in movies predicts level of alcohol use (ever use plus ever and recent binge drinking) and alcohol-related problems. A national sample of younger adolescents was interviewed by telephone with 4 repeated assessments spaced at 8-month intervals. A structural equation modeling analysis performed for ever-drinkers at Time 3 (N = 961) indicated that, controlling for a number of covariates, movie alcohol exposure at Time 1 was related to increases in peer alcohol use and adolescent alcohol use at Time 2. Movie exposure had indirect effects to alcohol use and problems at Times 3 and 4 through these pathways, with direct effects to problems from Time 1 rebelliousness and Time 2 movie exposure also found. Prospective risk-promoting effects were also found for alcohol expectancies, peer alcohol use, and availability of alcohol in the home; protective effects were found for mother’s responsiveness and for adolescent’s school performance and self-control. Theoretical and practical implications are discussed. PMID:19290687

  14. 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…

  15. 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

  16. 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…

  17. Multi-choice stochastic transportation problem involving general form of distributions.

    PubMed

    Quddoos, Abdul; Ull Hasan, Md Gulzar; Khalid, Mohammad Masood

    2014-01-01

    Many authors have presented studies of multi-choice stochastic transportation problem (MCSTP) where availability and demand parameters follow a particular probability distribution (such as exponential, weibull, cauchy or extreme value). In this paper an MCSTP is considered where availability and demand parameters follow general form of distribution and a generalized equivalent deterministic model (GMCSTP) of MCSTP is obtained. It is also shown that all previous models obtained by different authors can be deduced with the help of GMCSTP. MCSTP with pareto, power function or burr-XII distributions are also considered and equivalent deterministic models are obtained. To illustrate the proposed model two numerical examples are presented and solved using LINGO 13.0 software package. PMID:25332865

  18. Problems and possible solutions involved in hard target calibration of coherent Doppler lidar

    NASA Technical Reports Server (NTRS)

    Anderson, Richard

    1987-01-01

    The field of radiometry is surveyed with reference to coherent light, since the surfaces to be considered here are irradiated with coherent, polarized light. Definitions of some concepts are modified. In light of these modifications calibration problems are analyzed and solutions suggested. The most important task was to develop hard targets exhibiting minimal specular reflection (mirror-like and retroreflection) and following closely a Lambertian scattering curve. Bistable reflectometer experiments and integrating sphere measurements are used to physically characterize the targets. Optical and electron microscopy are used to physically characterize the targets. Since the BRDF matrix is not measured, this capability must be developed preferably for both bistatic and monostatic reflectometer measurements. The equipment is expensive and not yet developed. Calibration can be simplified if it can be proved that the BRDF matrix is diagonal for a diffuse scatterer.

  19. Risk-taking and alcohol use disorders symptomatology in a sample of problem drinkers.

    PubMed

    Ashenhurst, James R; Jentsch, J David; Ray, Lara A

    2011-10-01

    The relationship between risk-taking behavior and alcohol use disorder (AUD) symptoms is poorly understood. This study employed a modified version of a behavioral measure of risk-taking, the Balloon Analogue Risk Task (BART), to examine its relationship to alcohol use and related symptoms in a community sample of individuals with or at risk for AUD. A total of 158 (71.9% male) participants completed a testing battery that included the BART, a structured diagnostic interview for AUD, and measures of alcohol use and related problems. Estimates of IQ and working memory were assessed as covariates. Results indicated that the relationship between risk-taking propensity, as assessed by the BART, and alcohol problems was significant and negative. Individuals with higher symptom count made fewer pumps per trial on the BART, indicating less risk-taking. It is important to note that this relationship was attenuated when controlling for estimated IQ and working memory span. Further examination demonstrated that IQ and age mediated the relationship between risk-taking propensity and symptom count. The main negative relationship observed between risk-taking on the BART and alcohol use and AUD symptomatology in this sample stands in contrast to the positive relationships observed in adolescent and nonclinical samples. Together, these findings highlight the need to consider development and the course of addiction to fully elucidate the effects of risky-decision making on AUD liability. Furthermore, our results demonstrate the importance of inclusion of neurocognitive covariates (IQ), as well as demographic variables (age) when using this task. PMID:21707191

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

    PubMed

    Ba?ak, 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

  1. 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.

  2. Joint Associations of Residential Density and Neighborhood Involvement With Physical Activity Among a Multiethnic Sample of Urban Adults.

    PubMed

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

    2015-08-01

    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 adults in Detroit, Michigan, multilevel models were used to examine joint effects of residential density and resident involvement in neighborhood activities in relation to physical activity. We found a marginally significant negative interaction of higher residential density and resident neighborhood involvement. Higher residential density was negatively associated with physical activity, and resident neighborhood involvement was positively associated with physical activity. Our findings suggest that future work incorporate additional neighborhood and individual-level characteristics to understand the complexity of the association between the neighborhood environment, resident social engagement in the neighborhood, and physical activity. PMID:25626432

  3. 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…

  4. Examining the Criterion Validity of CBCL and TRF Problem Scales and Items in a Large Singapore Sample

    ERIC Educational Resources Information Center

    Ang, Rebecca P.; Rescorla, Leslie A.; Achenbach, Thomas M.; Ooi, Yoon Phaik; Fung, Daniel S. S.; Woo, Bernardine

    2012-01-01

    This study examined the criterion validity of the Child Behavior Checklist (CBCL) and Teacher's Report Form (TRF) problem scales and items in demographically-matched Singapore samples of referred and non-referred children (840 in each sample for the CBCL and 447 in each sample for the TRF). Internal consistency estimates for both the CBCL and TRF

  5. 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

  6. Sample treatment methods involving combinatorial peptide ligand libraries for improved proteomes analyses.

    PubMed

    Righetti, Pier Giorgio; Boschetti, Egisto

    2015-01-01

    If used in an optimized manner, the technology of combinatorial peptide solid-phase libraries can easily improve the analytical determinations of proteomes by several factors. The discovery of novel species and of early stage biomarkers becomes thus reachable with a simple sample treatment. This report describes the most important point to consider (overloading and full recovery) along with a minimum scientific background and gives then detailed recipes to laboratory technicians. Orientations for optional routes are also given according to the objective of the experimental investigations. This covers different approaches to capture proteins of very low abundance. Total protein harvestings to prevent partial losses are also described such as single exhaustive desorption and fractionated elutions for more detailed analyses. Documented results are also reported demonstrating the capability of the technology well beyond what is the common assumption. PMID:25384740

  7. 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 exist with handling and removing the very low levels of amino acids from Mars meteorites and returned samples.

  8. Correcting for the sampling bias problem in spike train information measures.

    PubMed

    Panzeri, Stefano; Senatore, Riccardo; Montemurro, Marcelo A; Petersen, Rasmus S

    2007-09-01

    Information Theory enables the quantification of how much information a neuronal response carries about external stimuli and is hence a natural analytic framework for studying neural coding. The main difficulty in its practical application to spike train analysis is that estimates of neuronal information from experimental data are prone to a systematic error (called "bias"). This bias is an inevitable consequence of the limited number of stimulus-response samples that it is possible to record in a real experiment. In this paper, we first explain the origin and the implications of the bias problem in spike train analysis. We then review and evaluate some recent general-purpose methods to correct for sampling bias: the Panzeri-Treves, Quadratic Extrapolation, Best Universal Bound, Nemenman-Shafee-Bialek procedures, and a recently proposed shuffling bias reduction procedure. Finally, we make practical recommendations for the accurate computation of information from spike trains. Our main recommendation is to estimate information using the shuffling bias reduction procedure in combination with one of the other four general purpose bias reduction procedures mentioned in the preceding text. This provides information estimates with acceptable variance and which are unbiased even when the number of trials per stimulus is as small as the number of possible discrete neuronal responses. PMID:17615128

  9. 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.

  10. Sustained impact of inattention and hyperactivity-impulsivity on peer problems: mediating roles of prosocial skills and conduct problems in a community sample of children.

    PubMed

    Andrade, Brendan F; Tannock, Rosemary

    2014-06-01

    This prospective 2-year longitudinal study tested whether inattentive and hyperactive/impulsive symptom dimensions predicted future peer problems, when accounting for concurrent conduct problems and prosocial skills. A community sample of 492 children (49% female) who ranged in age from 6 to 10years (M=8.6, SD=.93) was recruited. Teacher reports of children's inattention, and hyperactivity/impulsivity symptoms, conduct problems, prosocial skills and peer problems were collected in two consecutive school years. Elevated inattention and hyperactivity/impulsivity in Year-1 predicted greater peer problems in Year-2. Conduct problems in the first and second years of the study were associated with more peer problems, and explained a portion of the relationship between inattention and hyperactivity/impulsivity with peer problems. However, prosocial skills were associated with fewer peer problems in children with elevated inattention and hyperactivity/impulsivity. Inattention and hyperactivity/impulsivity have negative effects on children's peer functioning after 1-year, but concurrent conduct problems and prosocial skills have important and opposing impacts on these associations. PMID:24013840

  11. 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 ?-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

  12. 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.

  13. Profiles of Systems Involvement in a Sample of High-Risk Urban Adolescents with Unmet Treatment Needs

    PubMed Central

    Dauber, Sarah; Hogue, Aaron

    2011-01-01

    This study examined profiles of involvement in four systems (education, child welfare, legal, and treatment) in a sample of 253 high-risk urban adolescents with unmet behavioral health needs. Self-report data were collected on multiple dimensions of involvement within each system, demographics, and DSM-IV diagnoses. Latent class analysis revealed four profiles: Education System: Academic and Disciplinary, Education System: Academic Only, Legal/Juvenile Justice Involved, and Multiple Systems/Child Welfare. Profiles differed based on gender and psychiatric diagnoses. Boys were overrepresented in Education System: Academic and Disciplinary and Legal/Juvenile Justice Involved, and girls were overrepresented in Multiple Systems/Child Welfare. The two education system focused classes were characterized by depressive disorders and ADHD. Youth in Legal/Juvenile Justice Involved and Multiple Systems/Child Welfare were characterized by conduct disorder and substance abuse. Implications for assessment and treatment planning for high-risk youth and for the organization of community-based behavioral health services are discussed. PMID:21927525

  14. 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

  15. 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

  16. 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

  17. 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 culturally sensitive approaches when children are struggling. PMID:21804680

  18. Temporal stability of DSM-5 posttraumatic stress disorder criteria in a problem-drinking sample.

    PubMed

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

    2014-12-01

    The 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) reformulated posttraumatic stress disorder (PTSD) based partially on research showing there were 4 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 3 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 (Brief et al., 2013). We administered the PCL-5 at baseline, 8-week postintervention, 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 confirmed the results of previous research supporting the DSM-5 model of PTSD symptoms (Elhai et al., 2012; Miller et al., 2013). This is the 1st study to demonstrate the temporal stability of the PCL-5, indicating its use in longitudinal studies measures the same construct over time. PMID:24932642

  19. Psychiatric symptoms and substance use disorders in a nationally representative sample of American adolescents involved with foster care

    PubMed Central

    Pilowsky, Daniel J; Wu, Li-Tzy

    2006-01-01

    Objective To ascertain the prevalence of psychiatric symptoms and substance use disorders among adolescents with a lifetime history of foster care placement, using data from a nationally representative sample of US adolescents. Methods We studied adolescents aged 12–17 in the public use file of the 2000 National Household on Drug Abuse (N = 19,430, including 464 adolescents with history of foster care placement). Psychiatric symptoms and substance use disorders were ascertained through direct interviewing of adolescents. Logistic regression analyses were used to estimate the odds of past-year psychiatric symptoms and substance use disorders among adolescents involved with foster care, as compared to those without a lifetime history of foster care placement (comparison group) Results Adolescents involved with foster care had more past-year psychiatric symptoms, and especially more conduct symptoms, and past-year substance use disorders than those never placed in foster care. Adolescents involved with foster care were about four times more likely to have attempted suicide in the preceding 12 months (AOR, 3.95; 95% CI 2.78, 5.61), and about five times more likely to receive a drug dependence diagnosis in the same period (AOR, 4.81; 95% CI, 3.22, 7.18). Conclusions Adolescents involved with foster care have a higher prevalence of psychiatric symptoms and drug use disorders than those never placed in foster care. Additionally, the results of this study suggest that they may be at elevated risk for suicide attempts PMID:16549295

  20. 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

  1. 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…

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

    PubMed Central

    Mrmann, Lisandra; dos Santos, Maria Ceclia; Longaray, Solange Mendes; Both, Jane Mari Corra; 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

  3. Prospective relationship between poor sleep and substance-related problems in a national sample of adolescents

    PubMed Central

    Wong, Maria M.; Roberson, Gail; Dyson, Rachel

    2014-01-01

    Background Previous studies showed that poor sleep prospectively predicted alcohol related problems and illicit drug use in adolescents and young adults (Wong et al., 2010, 2012). However, more works needs to be done to elucidate the nature of these problems. The purpose of this study was to examine whether sleep difficulties and hours of sleep prospectively predicted several serious substance related problems, e.g., binge drinking, driving under the influence of alcohol, risky sexual behavior. Methods Study participants were 6504 adolescents from the National Longitudinal Study of Adolescent Health (ADD HEALTH). Data were collected from interviews and questionnaires. The current study analyzed data from the first three waves of data (T1: 199495; T2: 1996; T3: 200102). In all analyses, we used sleep difficulties at a previous wave to predict substance-related problems at a subsequent wave, while controlling for substance-related problems at a previous wave. Results Holding T1 alcohol-related problems constant, sleep difficulties at T1 significantly predicted alcohol-related interpersonal problems, binge drinking, gotten drunk or very high on alcohol, driving under the influence of alcohol, getting into a sexual situation one later regretted due to drinking, ever using any illicit drugs and drugs-related problems at T2. T1 hours of sleep negatively predicted T2 alcohol-related interpersonal problems and binge drinking. The relationship between T2 sleep variables and T3 substance-related problems were consistent with previous waves, though the effect was weaker. Conclusions Sleep difficulties and hours of sleep are a significant predictor of a number of substance-related problems. It may be useful to educate adolescents about the importance of sleep, sleep hygiene and the potential consequences of poor sleep on drinking and related behaviors. PMID:25598438

  4. 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.…

  5. 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.

  6. Sampling Procedures Used for National Surveys of Public School Teachers--Problems and Possible Solutions.

    ERIC Educational Resources Information Center

    Pena, Deagelia M.; Henderson, Ronald D.

    The sampling of teachers for nationwide surveys offers a challenging endeavor in obtaining a representative and adequate sample to truly represent opinions of the teachers. Ten national surveys of public school teachers conducted between 1980 and 1985 are presented with respect to their sampling design and procedures. Concepts and theoretical…

  7. Stress, Mental Health and Substance Abuse Problems In a Sample of Diversion Program Youth: An Exploratory Latent Class Analysis*

    PubMed Central

    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, mental health and substance abuse issues, Group 2: youths with low levels of these problems. Comparison of these two groups on a variety of psychosocial measures and parent/guardian reports found differences between them that were consistent with their problem group classification. Follow-up analysis confirmed problem behavior that was consistent with the youths latent class placement. Implications of the findings for research and practice will be presented. PMID:22685378

  8. 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…

  9. 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

  10. When is enough, enough? Understanding and solving your sample size problems in health services research.

    PubMed

    Pye, Victoria; Taylor, Natalie; Clay-Williams, Robyn; Braithwaite, Jeffrey

    2016-01-01

    Health services researchers face two obstacles to sample size calculation: inaccessible, highly specialised or overly technical literature, and difficulty securing methodologists during the planning stages of research. The purpose of this article is to provide pragmatic sample size calculation guidance for researchers who are designing a health services study. We aimed to create a simplified and generalizable process for sample size calculation, by (1) summarising key factors and considerations in determining a sample size, (2) developing practical steps for researchers-illustrated by a case study and, (3) providing a list of resources to steer researchers to the next stage of their calculations. Health services researchers can use this guidance to improve their understanding of sample size calculation, and implement these steps in their research practice. PMID:26867928

  11. 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. (PsycINFO Database Record PMID:25894703

  12. 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.

  13. 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.…

  14. 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

  15. A latent class analysis of underage problem drinking: evidence from a community sample of 16-20 year olds.

    PubMed

    Reboussin, Beth A; Song, Eun-Young; Shrestha, Anshu; Lohman, Kurt K; Wolfson, Mark

    2006-07-27

    The aim of this paper is to shed light on the nature of underage problem drinking by using an empirically based method to characterize the variation in patterns of drinking in a community sample of underage drinkers. A total of 4056 16-20-year-old current drinkers from 212 communities in the US were surveyed by telephone as part of the National Evaluation of the Enforcing Underage Drinking Laws (EUDL) Program. Latent class models were used to create homogenous groups of drinkers with similar drinking patterns defined by multiple indicators of drinking behaviors and alcohol-related problems. Two types of underage problem drinkers were identified; risky drinkers (30%) and regular drinkers (27%). The most prominent behaviors among both types of underage problem drinkers were binge drinking and getting drunk. Being male, other drug use, early onset drinking and beliefs about friends drinking and getting drunk were all associated with an increased risk of being a problem drinker after adjustment for other factors. Beliefs that most friends drink and current marijuana use were the strongest predictors of both risky problem drinking (OR=4.0; 95% CI=3.1, 5.1 and OR=4.0; 95% CI=2.8, 5.6, respectively) and regular problem drinking (OR=10.8; 95% CI=7.0, 16.7 and OR=10.2; 95% CI=6.9, 15.2). Young adulthood (ages 18-20) was significantly associated with regular problem drinking but not risky problem drinking. The belief that most friends get drunk weekly was the strongest discriminator of risky and regular problem drinking patterns (OR=5.3; 95% CI=3.9, 7.1). These findings suggest that underage problem drinking is most strongly characterized by heavy drinking behaviors which can emerge in late adolescence and underscores its association with perceptions regarding friends drinking behaviors and illicit drug use. PMID:16359829

  16. Study of the stability problems of 110mAg samples in several commercial liquid scintillators

    PubMed

    Rodriguez Barquero L; Los Arcos JM

    2000-03-01

    The stability of 110mAg samples for liquid scintillation measurements has been studied in four commercial scintillators: Insta-Gel Plus, Ultima-Gold, HiSafe II and HiSafe III. Samples using 15 ml of cocktail with four different levels of carrier, 0.0, 1.5, 3.0 and 6.0 microg of AgNO3, were prepared and their total count rate and spectral behaviour monitored for two months. Only samples in HiSafe III were completely stable for the full term studied. PMID:10724426

  17. 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

  18. 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%])

  19. 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…

  20. 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%])…

  1. 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 may predict important consumer variables such as satisfaction. Findings emphasize that initial goals disagreement warrants careful assessment and monitoring. PMID:25638516

  2. 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.

  3. 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.

  4. Problems found using a radon stripping algorithm for retrospective assessment of air filter samples.

    PubMed

    Hayes, Robert B

    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 sources, 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 from pure Pu on air sample filters (not due to radon progeny) around the 200 disintegrations per minute level. PMID:18332729

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. Health problems and help-seeking in a nationwide sample of operational Norwegian ambulance personnel

    PubMed Central

    Sterud, Tom; Hem, Erlend; Ekeberg, ivind; Lau, Bjrn

    2008-01-01

    Background To estimate the prevalence of anxiety and depression symptoms, and their association with professional help-seeking, among operational ambulance personnel and a general working population, and to study the symptoms of musculoskeletal pain and disturbed sleep among ambulance personnel. Methods The results of a comprehensive nationwide questionnaire survey of operational ambulance personnel (n = 1180) were compared with the findings of a population-based Norwegian health study of working people (n = 31,987). The questionnaire included measures of help-seeking, the Hospital Anxiety and Depression Scale, the Subjective Health Complaints Questionnaire, the Karolinska Sleep Questionnaire and the Need for Recovery after Work Scale. Results Compared with those in the reference population, the mean of level anxiety symptoms in the ambulance sample was lower for men (3.5 vs. 3.9, P <0.001) and women (4.0 vs. 4.4, P <0.05), and the mean level of depression symptoms in ambulance workers was lower for men (2.3 vs. 2.8, P <0.05) but not for women (2.9 vs. 3.1, P = 0.22). A model adjusted for anxiety and depression symptoms indicated that ambulance personnel had lower levels of help-seeking except for seeing a chiropractor (12% vs. 5%, P <0.01). In the ambulance sample, symptoms of musculoskeletal pain were most consistently associated with help-seeking. In the adjusted model, only symptoms of disturbed sleep were associated with help-seeking from a psychologist/psychiatrist (total sample = 2.3%). Help-seeking was more often reported by women but was largely unaffected by age. Conclusion The assumption that ambulance personnel have more anxiety and depression symptoms than the general working population was not supported. The level of musculoskeletal pain and, accordingly, the level of help-seeking from a chiropractor were higher for ambulance workers. More research should address the physical strains among ambulance personnel. PMID:18177497

  10. Peculiar velocities in large-scale structure - The problem of incomplete sampling. [Of galactic clusters

    SciTech Connect

    Bothun, G.D.; West, M.J.; Mould, J.R.; Schommer, R.A. Palomar Observatory, Pasadena, CA Observatorio Interamericano de Cerro Tololo, La Serena )

    1990-04-01

    Using N-body simulations of gravitational clustering scenarios with various amounts of power on large scales, the nature of observed peculiar velocity field that arises when incompletely sampling a distant but very large structure is examined. Consideration is given to the effect of placing the centroid of a large mass distribution at a distance of 45/h Mpc from the observer and imposing a distance cutoff such that only the near side of this mass distribution is actually sampled. Under these circumstances, simulations with significant large-scale power produce clusters which can have mean peculiar velocities of as high as 600 km/s, but this is rare. A more typical value is 300-400 km/s. The effects of projection, distance errors, and cluster internal velocity dispersion on the observed peculiar velocity field are evaluated. It is concluded that much of the cluster peculiar velocities are due to infall at or near the turnaround radius of the largest structure at the simulation center. 65 refs.

  11. 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.

  12. Cognitive Analysis of U.S. and Chinese Students' Mathematical Performance on Tasks Involving Computation, Simple Problem Solving, and Complex Problem Solving.

    ERIC Educational Resources Information Center

    Cai, Jinfa

    1995-01-01

    This document is 7th in the Journal for Research in Mathematics Education monograph series. The mathematical performance of (n=250) U.S. 6th-grade students from both private and public schools and (n=425) Chinese 6th-graders from both key and common schools was examined on multiple-choice tasks assessing computation and simple problem solving, and…

  13. 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.

  14. [Analytical problems in examination of small amounts of blood samples taken from law offenders].

    PubMed

    Celi?ski, Rafa?; Kulikowska, Joanna; Albert, Ma?gorzata; Sybirska, Halina

    2002-01-01

    In the paper there have presented results of the analysis of small blood samples taken routinely from 3 cases after car accidents and 1 rapist. Fluorescence polarisation immunoassay (FPIA, Abott) was used for screening examinations of narcotics from the group of both opium and cocaine alkaloids, barbituric acid and benzodiazepine and also drugs from the group of tricyclic antidepressants. Confirmation of the obtained results and full identification of the substances analysed were carried out by liquid chromatography with mass spectrometry (LC-MS). In the causes of car accidents components of "compote" were found (poppy straw extract) morphine and codeine (1 case), cocaine (1 case) and also tramadol and diazepam (1 case) were also found. In the rapist methylenedioxymethamphetamine (MDMA) was determined. PMID:14669694

  15. 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.

  16. 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…

  17. 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

  18. The Effects of the Family-Involved SDLMI on Academic Engagement and Goal Attainment of Middle School Students with Disabilities Who Exhibit Problem Behavior

    ERIC Educational Resources Information Center

    Kim, Nam Hee; Park, Jiyeon

    2012-01-01

    The purpose of this study is to investigate the effects of the Family-Involved Self-Determination Learning Model of Instruction (SDLMI) on academic engagement and goal attainment of middle school students with disabilities who exhibit problem behavior. Intervention was provided to the experimental group (12 students with their families and special

  19. 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

  20. FIBER AND INTEGRATED OPTICS: Problems involved in the profiling of quantum wells and barriers for optoelectronic applications

    NASA Astrophysics Data System (ADS)

    Eliseev, P. G.; Zakhar'ev, B. N.

    1992-10-01

    Some important problems concerning the profiling of the potential energy in quantum-well lasers are discussed. The goals being sought are to introduce a relative shift of the levels of localized states, to introduce an energy gap, and to reduce the transmission of barriers without increasing their height.

  1. 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

  2. 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…

  3. Associations between work family conflict, emotional exhaustion, musculoskeletal pain, and gastrointestinal problems in a sample of business travelers.

    PubMed

    Jensen, Maria Therese; Rundmo, Torbjrn

    2015-02-01

    The aim of the study was to examine the associations among work-family conflict (WFC), emotional exhaustion, musculoskeletal (MS) pain, and gastrointestinal problems on a sample of business travelers (n = 2,093). An additional aim was to examine differences in the mentioned relationships among three traveler groups: commuters, national travelers, and international travelers. The study was conducted in a large Norwegian oil and gas company, and the company's business travel database was utilized to examine business travel. Structural equation modeling (SEM) revealed significant relations between WFC and emotional exhaustion and between emotional exhaustion and health problems. Contrary to the expectations, no direct association was found between WFC and health problems. However, we found that emotional exhaustion mediated the relation between WFC and health outcomes. The results from multi-group analysis revealed that associations among WFC, emotional exhaustion, and health-outcomes showed a similar pattern for commuters, national travelers, and international travelers. However, the association between emotional exhaustion and MS pain proved to be significantly stronger for the commuter group compared to the national and international travel groups. Practical implications and the consequences of these findings for future research are discussed. PMID:25363417

  4. 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

  5. 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

  6. 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…

  7. 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

  8. Subjective Experiences in Activity Involvement and Perceptions of Growth in a Sample of First-Year Female University Students

    ERIC Educational Resources Information Center

    Busseri, Michael A.; Rose-Krasnor, Linda

    2008-01-01

    We examined subjective experiences in activities and perceptions of growth in a sample of first-year female university students (N = 196; age range = 17 to 19 years old, M = 18.48, SD = 0.53; the most common ethnic affiliations were British Isles, 51% of respondents, Canadian, 34%, French, 14%, and German, 8%). Students described 4 activities,…

  9. PeptideManager: a peptide selection tool for targeted proteomic studies involving mixed samples from different species

    PubMed Central

    Demeure, Kevin; Duriez, Elodie; Domon, Bruno; Niclou, Simone P.

    2014-01-01

    The search for clinically useful protein biomarkers using advanced mass spectrometry approaches represents a major focus in cancer research. However, the direct analysis of human samples may be challenging due to limited availability, the absence of appropriate control samples, or the large background variability observed in patient material. As an alternative approach, human tumors orthotopically implanted into a different species (xenografts) are clinically relevant models that have proven their utility in pre-clinical research. Patient derived xenografts for glioblastoma have been extensively characterized in our laboratory and have been shown to retain the characteristics of the parental tumor at the phenotypic and genetic level. Such models were also found to adequately mimic the behavior and treatment response of human tumors. The reproducibility of such xenograft models, the possibility to identify their host background and perform tumor-host interaction studies, are major advantages over the direct analysis of human samples. At the proteome level, the analysis of xenograft samples is challenged by the presence of proteins from two different species which, depending on tumor size, type or location, often appear at variable ratios. Any proteomics approach aimed at quantifying proteins within such samples must consider the identification of species specific peptides in order to avoid biases introduced by the host proteome. Here, we present an in-house methodology and tool developed to select peptides used as surrogates for protein candidates from a defined proteome (e.g., human) in a host proteome background (e.g., mouse, rat) suited for a mass spectrometry analysis. The tools presented here are applicable to any species specific proteome, provided a protein database is available. By linking the information from both proteomes, PeptideManager significantly facilitates and expedites the selection of peptides used as surrogates to analyze proteins of interest. PMID:25228907

  10. 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

  11. A framework for analyzing and responding to the equity problems involved in high-level radioactive waste disposal

    SciTech Connect

    Kasperson, R.E.; Ratick, S.; Renn, O.

    1988-06-01

    As used in the discussion that follows, and in our research papers treating equity in the Yucca Mountain Socioeconomic Impact Study, equity refers to the fairness of the process or results of a particular activity or development on the various affected groups or individuals. The proper role for equity analyses, in our view, is not to provide final answers for the difficult issues involved. Any such solutions would require absolute values to which all interested and affected parties would subscribe. They would also require agreement as to the meaning of ``harm,`` ``benefit,`` and ``burden`` as well as how these factors should most appropriately be measured and valued. Such absolute values and social consensus is not realistic. So no overall quantitative expression of the amount of inequity can be definitively calculated or stated.

  12. The Determination of Ergosterol in Environmental Samples. An Interdisciplinary Project Involving Techniques of Analytical and Organic Chemistry

    NASA Astrophysics Data System (ADS)

    Volker, Eugene J.; Dilella, Dan; Terneus, Kim; Baldwin, Carson; Volker, Ilona

    2000-12-01

    In this undergraduate laboratory experiment, a naturally formed steroid that is an important environmental indicator of biological activity is extracted and quantified. The target compound is ergosterol, a steroid found only in fungi and an accepted measure of fungal biomass. Maple leaves were used as a representative sample, but the procedure can be extended to soils, fruits, and grains. The environmental sample is first saponified with methanolic KOH to release ergosterol from any bound forms. Next, the steroid is transferred into pentane to separate it from the polar components of the initial extract. After evaporation of the pentane, the residue containing the steroid is dissolved in methanol and filtered. This solution is analyzed on an HPLC instrument equipped with a reversed-phase column. Typical values for ergosterol in the maple leaf samples analyzed ranged from 22 to 240 mg/g of dry leaf. Leaves collected shortly after falling have low values, and those collected later have progressively higher values. The experiment has been tested in Analytical Chemistry, Environmental Chemistry, and Organic Chemistry classes and can be performed in two 3-hour laboratory periods.

  13. Numerical study of heat transfer problems in two-phase flows involving temperature distribution within dispersed solid particles

    NASA Astrophysics Data System (ADS)

    Takeuchi, Shintaro; Kajishima, Takeo

    2015-12-01

    Heat transfer in solid-dispersed two-phase flow is simulated, and the effects of temperature distribution within the finite-sized particles on the flow structure, particle behaviour and heat transfer are studied. Temperature distribution within the particles is solved by an interfacial heat flux model with the discrete temperature field. The interfacial heat conduction model is validated through a comparison with the analytical solution of the heat conduction through eccentric cylinders of constant temperature difference. The method is applied to 2-D and 3-D natural convection problems in a confined container under relatively low Rayleigh numbers (104 />˜/> 106). Particle behaviours are studied for different heat conductivity ratios (solid to fluid) ranging between 10-3 and 102. With particles of relatively low heat conductivity ratios (< 100), the particles show a simple circulating flow around the domain centre. By increasing the heat conductivity ratio(> 101), particulate flow structure shows a transition to oscillatory modes around the domain centre. The difference in the time scales of heat transfer through the fluid and solid is found to be responsible for determining the the oscillation frequency. The results highlight the importance of temperature distributions within finite-sized particles.

  14. 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

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

    PubMed

    Yunus, Agha W; Sulyok, Michael; Bhm, 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

  16. 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.

  17. A Population of Langerin-Positive Dendritic Cells in Murine Peyer's Patches Involved in Sampling β-Glucan Microparticles

    PubMed Central

    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 context of the GALT. PMID:24632738

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

    PubMed

    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

  19. 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.

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. Negative affect mediates the relationship between interpersonal problems and binge-eating disorder symptoms and psychopathology in a clinical sample: a test of the interpersonal model.

    PubMed

    Ivanova, Iryna V; Tasca, Giorgio A; Hammond, Nicole; Balfour, Louise; Ritchie, Kerri; Koszycki, Diana; Bissada, Hany

    2015-03-01

    This study evaluated the validity of the interpersonal model of binge-eating disorder (BED) psychopathology in a clinical sample of women with BED. Data from a cross-sectional sample of 255 women with BED were examined for the direct effects of interpersonal problems on BED symptoms and psychopathology, and indirect effects mediated by negative affect. Structural equation modelling analyses demonstrated that higher levels of interpersonal problems were associated with greater negative affect, and greater negative affect was associated with higher frequency of BED symptoms and psychopathology. There was a significant indirect effect of interpersonal problems on BED symptoms and psychopathology mediated through negative affect. Interpersonal problems may lead to greater BED symptoms and psychopathology, and this relationship may be partially explained by elevated negative affect. The results of the study are the first to provide support for the interpersonal model of BED symptoms and psychopathology in a clinical sample of women. PMID:25582510

  6. 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

  7. 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…

  8. 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

  9. Parent-Reported Attention-Deficit/Hyperactivity Disorder Symptomatology and Sleep Problems in a Preschool-Age Pediatric Clinic Sample

    ERIC Educational Resources Information Center

    Willoughby, Michael T.; Angold, Adrian; Egger, Helen L.

    2008-01-01

    The study investigates the relation between attention-deficit/hyperactivity disorder symptomatology and parent-reported sleep problems among preschoolers aged 2 to 5 years. Results indicate that neither condition was uniquely related to parent-reported sleep problems, but inattentive symptomatology was uniquely associated with daytime sleepiness.

  10. Differences in Parent and Teacher Ratings of Preschool Problem Behavior in a National Sample: The Significance of Gender and SES

    ERIC Educational Resources Information Center

    Graves, Scott L., Jr.; Blake, Jamilia; Kim, Eun Sook

    2012-01-01

    Previous research has demonstrated that informant disagreement is common with the use of rating scales to assess problem behavior in school-age populations. However, much less is known about this phenomenon in preschool populations. This is important because the accurate assessment of problem behavior in preschool is complex due to the rapid…

  11. 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,

  12. 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,…

  13. Sleep problems and daytime somnolence in a German population-based sample of snoring school-aged children.

    PubMed

    Eitner, Steffen; Urschitz, Michael S; Guenther, Anke; Urschitz-Duprat, Pilar M; Bohnhorst, Bettina; Schlaud, Martin; Poets, Christian F

    2007-03-01

    Habitual snoring is associated with daytime symptoms like tiredness and behavioral problems. Its association with sleep problems is unclear. We aimed to assess associations between habitual snoring and sleep problems in primary school children. The design was a population-based cross-sectional study with a nested cohort study. The setting was twenty-seven primary schools in the city of Hannover, Germany. Habitual snoring and sleep problems were assessed in primary school children using an extended version of Gozal's sleep-disordered breathing questionnaire (n = 1144). Approximately 1 year later, parents of children reported to snore habitually (n = 114) and an equal number of children who snored never or occasionally were given the Sleep Disturbance Scale for Children, a validated questionnaire for the assessment of pediatric sleep problems. Snoring status was re-assessed using the initial questionnaire and children were then classified as long-term habitual snorers or ex-habitual snorers. An increasing prevalence of sleep problems was found with increasing snoring frequency for sleep-onset delay, night awakenings, and nightmares. Long-term habitual snorers were at significantly increased risk for sleep-wake transition disorders (e.g. rhythmic movements, hypnic jerks, sleeptalking, bruxism; odds ratio, 95% confidence interval: 12.0, 3.8-37.3), sleep hyperhidrosis (3.6, 1.2-10.8), disorders of arousal/nightmares (e.g. sleepwalking, sleep terrors, nightmares; 4.6, 1.3-15.6), and excessive somnolence (i.e. difficulty waking up, morning tiredness, daytime somnolence; 6.3, 2.2-17.8). Ex-habitual snorers were at increased risk for sleep-wake transition disorders (4.4, 1.4-14.2). Habitual snoring was associated with several sleep problems in our study. Long-term habitual snorers were more likely to have sleep problems than children who had stopped snoring spontaneously. PMID:17309768

  14. Pervasive and Non-Pervasive Conduct Problems in a Clinic Sample Aged 4-8 Years: Child, Family and Day-Care/School Factors

    ERIC Educational Resources Information Center

    Drugli, May Britt; Larsson, Bo; Clifford, Graham; Fossum, Sturla

    2007-01-01

    Differences between pervasive (home and day-care/school) versus non-pervasive (home only) conduct problems were examined in regard to various child, parent/family, and day-care/school characteristics in an outpatient clinic sample of 120 children aged 4-8 years. All children scored above the 90th percentile on the Eyberg Child Behavior Inventory…

  15. 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

  16. Diagnostic Performance of the CBCL-Attention Problem Scale as a Screening Measure in a Sample of Brazilian Children with ADHD

    ERIC Educational Resources Information Center

    Lampert, T. L.; Polanczyk, G.; Tramontina, S.; Mardini, V.; Rohde, L. A.

    2004-01-01

    Objective: To evaluate the diagnostic performance of the Attention Problem Scale of the Child Behavior Checklist (CBCL-APS) for the screening of Attention-Deficit/Hyperactivity Disorder (ADHD) in a sample of Brazilian children and adolescents. Methods: The CBCL-APS was given to 763 children and adolescents. Child psychiatrists using DSM-IV

  17. 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

  18. 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…

  19. Diagnostic Performance of the CBCL-Attention Problem Scale as a Screening Measure in a Sample of Brazilian Children with ADHD

    ERIC Educational Resources Information Center

    Lampert, T. L.; Polanczyk, G.; Tramontina, S.; Mardini, V.; Rohde, L. A.

    2004-01-01

    Objective: To evaluate the diagnostic performance of the Attention Problem Scale of the Child Behavior Checklist (CBCL-APS) for the screening of Attention-Deficit/Hyperactivity Disorder (ADHD) in a sample of Brazilian children and adolescents. Methods: The CBCL-APS was given to 763 children and adolescents. Child psychiatrists using DSM-IV…

  20. Epidemiological study on behavioural and emotional problems in developmental age: prevalence in a sample of Italian children, based on parent and teacher reports

    PubMed Central

    2014-01-01

    Background The aim of this study is to examine the prevalence of behavioural and emotional problems in a sample of school children living in Campania, a region of South Italy. Methods The Child Behavior Checklist (CBCL) Parent Report Form (PRF) and the CBCL Teacher Rating Form (TRF) were administered to parents and teachers of a sample of school children aged 8-9yr. Results The subjects (SS) eligible for the study were 3072. In 2137 (69.5%) cases parents returned the envelopes back. 1228 (57.4%) subjects were excluded because of lack of signed consensus, unfilled or incomplete forms. Parents reported childrens behavioural or emotional Total Problems in 14.7% of the SS. (5.2% borderline, 9.5% clinical), Internalizing Problems in 18.5% (8.0% borderline, 10.5% clinical), and Externalizing Problems in 8.5% (3.8% borderline, 4.7% clinical) respectively. At the Competence Scale of CBCL more than 2/3 of the sample show high rate for Total Competence Problem (24.3% borderline, 47.3% clinical.) Teachers reported 8.7% of SS having Total Problems, (4.3% borderline, 4.4% clinical), Internalizing problems were detected in 13.3% of the sample (4.9% borderline and 8.4% clinical), while Externalizing problems were reported for 9.6% of SS (4.1% borderline and 5.5% clinical). In the sub-scale of Academic Performances teachers report a high number of subjects with problems, 18.7%, whose 4.3% had a borderline score, and 14.4% had a clinical score. Conclusion Concerning Total Problems (clinical and borderline SS, 14.7% as reported by parents, 8.7% as reported by teachers) we obtained a prevalence similar to that reported in the rest of the country, with differences in gender (males 13.2%, females 16.0% as reported by parents; males 7.4%, females 9.7% as reported by teachers). The difficulties in social and relationship competencies area were higher (4/10 children). This datum should be cautiously evaluated because the possible inadequacy of CBCL competences scale. PMID:24533835

  1. Sample Sixth Grade Problem-Based Learning (PBL) Lesson: The Ancient World Explorers: Space Invaders, Copycats, or Independent Inventors.

    ERIC Educational Resources Information Center

    Benoit, Ty

    1998-01-01

    Outlines a social studies lesson plan that follows the Problem Based Learning model. Provides the lesson goal, questions for students, instructions for teachers and students, instructional materials, Internet resources for student research, preparation hints for teachers, and reflective learning questions for students at the end of the project.

  2. 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"…

  3. 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…

  4. 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"

  5. Psychological and health problems in a geographically proximate population time-sampled continuously for three months after the September 11th, 2001 terrorist incidents.

    PubMed

    Ford, Julian D; Adams, Mary L; Dailey, Wayne F

    2007-06-01

    This study assessed the mental and physical health status and psychological problems related to the September 11th terrorist incidents among a representative sample of adults living near New York City, using continuously time-sampled data collected throughout 2001. Prevalence estimates for poor mental or physical health after September 11th (October through December) were comparable to those for the entire year of 2001 (i.e. approximately 33%). Psychological problems related to the terrorist incidents were reported by more than half of the respondents, and appeared to peak in prevalence approximately two to three months following the incidents, followed by a decline in the next month and subsequent year. Poor mental health, female gender, media re-exposure, and ongoing or increased alcohol use were risk factors for psychological problems, while older age (65+ years old) and being married were protective factors. Risk factors for poor physical and mental health or psychological problems were generally stable over the three-month period following September 11th, but some changes were identified consistent with stage models of post-disaster psychological adjustment. Implications are discussed for using continuous time-sampling as a strategy to research patterns of relatively acute stress-related sequelae of terrorism in populations whose members are affected despite primarily not having been at the disaster epicenter. PMID:17999220

  6. 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

  7. Parallel mediation effects by sleep on the parental warmth-problem behavior links: evidence from national probability samples of Georgian and Swiss adolescents.

    PubMed

    Vazsonyi, Alexander T; Harris, Charlene; Terveer, Agnes M; Pagava, Karaman; Phagava, Helen; Michaud, Pierre-Andre

    2015-02-01

    Previous research has documented the importance of parenting on adolescent health and well-being; however, some of the underlying mechanisms that link the quality of parent-child relationship to health, adjustment, and well-being are not clearly understood. The current study seeks to address this gap by examining the extent to which sleep functioning mediates the effects by parental warmth on different measures of adolescent problem behaviors. Specifically, we test whether sleep functioning, operationalized by sleep quality and sleep quantity, mediates the relationship between the parental warmth and three measures of problem behaviors, namely alcohol use, illegal drug use, and deviance, in two nationally representative samples of Georgian (N = 6,992; M = 15.83, 60% females, and Swiss (N = 5,575; M = 17.17, 50% females) adolescents. Based on tests for parallel mediating effects by sleep functioning of parental warmth on problem behaviors in the MEDIATE macro in SPSS, the findings provided evidence that both sleep quality and sleep quantity independently and cumulatively mediated the effects of parental warmth on each of the three problem behaviors in both samples, with one exception. These results highlight the salience of positive parenting on sleep functioning among teens in two different cultural contexts, and, in turn, on measures of problem behaviors. PMID:25148792

  8. 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 before, during and after trials will help the research community to optimise PPI, although the need for ongoing flexibility in implementing PPI should also be recognised. PMID:25475243

  9. 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

  10. 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

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

    PubMed

    Roug-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

  12. 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

  13. 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…

  14. 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

  15. A simple method for overcoming some problems when observing thick reflective biological samples with a confocal scanning laser microscope.

    PubMed

    Rumio, C; Morini, M; Miani, A; Barajon, I; Castano, P

    1995-01-01

    A simple device is described, which allows the range of depth of scanning to be reduced when observing thick reflecting biological samples with a confocal scanning laser microscope (CSLM). Thick histological sections of human skin and rat brain stem were mounted between two coverslips ('sandwich' style) and the optical tomography was performed from both sides by turning the 'sandwich' upside-down. The samples were impregnated using standard Golgi-Cox, 'rapid Golgi' or other silver methods. The ability to turn the 'sandwich' upside-down is particularly useful when the reflective structure inspected is deep inside the section, i.e., near the lower surface of the specimen, or when it is opaque to the laser beam or excessively reflective. PMID:7897649

  16. 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.

  17. 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

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

    PubMed Central

    Farmer, Cristan; 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.

    2013-01-01

    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 (HSQ) and the Hyperactivity/Noncompliance subscale of the Aberrant Behavior Checklist were used as outcome measures. Candidate predictors and moderators included 21 demographics and baseline measures of behavior. Higher baseline HSQ scores predicted greater improvement on the HSQ regardless of treatment assignment, but no other predictors of outcome were observed. None of the variables measured in this study moderated response to PT. Antipsychotic medication plus PT appears to be equally effective for children with a wide range of demographic and behavioral characteristics. PMID:21822762

  19. Predictors and moderators of parent training efficacy in a sample of children with autism spectrum disorders and serious behavioral problems.

    PubMed

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

    2012-06-01

    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 (HSQ) and the Hyperactivity/Noncompliance subscale of the Aberrant Behavior Checklist were used as outcome measures. Candidate predictors and moderators included 21 demographics and baseline measures of behavior. Higher baseline HSQ scores predicted greater improvement on the HSQ regardless of treatment assignment, but no other predictors of outcome were observed. None of the variables measured in this study moderated response to PT. Antipsychotic medication plus PT appears to be equally effective for children with a wide range of demographic and behavioral characteristics. PMID:21822762

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

    NASA Astrophysics Data System (ADS)

    Halldrsson, 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.

  1. Atmospheric bulk deposition of soluble phosphorus in Ashiu Experimental Forest, Central Japan: source apportionment and sample contamination problem

    NASA Astrophysics Data System (ADS)

    Tsukuda, S.; Sugiyama, M.; Harita, Y.; Nishimura, K.

    Atmospheric bulk depositions of soluble reactive phosphorus (SRP), soluble unreactive phosphorus (SUP), soluble total phosphorus (STP), Na, SO 4, V and Mo were monitored for 3 years in Ashiu Experimental Forest in Central Japan. Relations among P, SO 4, V and Mo data were analyzed to determine if any part of P deposition is derived from fossil fuel combustion. Contamination by local particles was evaluated and its influence on atmospheric P input estimates was discussed. The mean bulk depositions of SRP, SUP, STP, Na, SO 4, V and Mo were 175, 76, 251, 156000, 40100, 10.3, and 1.52 ?mol m -2 year -1, respectively. Bulk depositions of Na, nss-SO 4, V and Mo were within the range of published data, while P deposition represented the lowest value found in literature. The low P deposition likely reflected the applied methodology to reduce sample contamination, i.e. (1) placement of samplers off the ground surface, (2) installation of multiple samplers, (3) rejection of samples with visible contamination, and (4) choosing the lowest values as the least contaminated. P and Na showed single peak during winter and spring, while nss-SO 4, V and Mo showed two peaks during winter and during summer. Nss-SO 4 and Mo data suggested that 59-89% of deposited STP was derived from fossil fuel combustion. Elemental composition of fossil fuels and airmass backward trajectories suggested that a large part of anthropogenic P originates from coal combustion in China. It was speculated that the rest (11-41%) of STP deposition might be predominantly attributed to contamination of local biogenic material. The result suggests that even after precautionary methodologies were employed, the data might still be affected by contamination. It should be remembered that one must take considerable care when interpreting P deposition data to evaluate atmospheric P input to terrestrial ecosystems.

  2. 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

  3. Effects of Childhood Conduct Problems and Family Adversity on Health, Health Behaviors, and Service Use in Early Adulthood: Tests of Developmental Pathways Involving Adolescent Risk Taking and Depression

    PubMed Central

    Herrenkohl, Todd I.; Kosterman, Rick; Mason, W. Alex; Hawkins, J. David; McCarty, Carolyn A.; McCauley, Elizabeth

    2010-01-01

    This study examined a developmental, cascade model that includes childhood risks of conduct problems and family adversity at age 10 12; conduct problems, risk taking, and internalizing during adolescence; and adult outcomes of conduct problems, poor health, health risks, depression, and service use at ages 27 and 30. Analyses showed that childhood conduct problems predicted adolescent conduct problems and risk taking, which, in turn, predicted adult conduct problems, health risks, depression, and service use. Childhood family adversity predicted adolescent internalizing, a predictor itself of poor health, depression, and service use at age 27. There was considerable continuity in the same adult outcomes measured over a 3-year period, as well as some cross-domain prediction from measures at age 27 to measures at age 30. Developmental patterns found in these data offer implications for future research and prevention. PMID:20576185

  4. 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.

  5. 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.

  6. 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

  7. [Outlook and problems of microbiological sampling in public catering establishments in light of the new European regulations].

    PubMed

    Amadei, Paolo; Biondi, Augusto; Tarsitani, Gianfranco; Antonini, Alessandra

    2008-01-01

    Modern society is structured in such a way that more food is eaten outside the home and therefore the hygienic standards of food production and organoleptic characteristics of foods provided by catering establishments is of increasing importance. In order to obtain a complete view of the hygienic standards of the food production cycle, however, it is not sufficient to show that pathogenic microroganisms are absent, but it is also useful to measure the number of microroganisms which do not constitute a hazard to health but whose presence may alter the quality of food products or be an index of inadequate hygienic practices. Microbiological testing plays a fundamental role in the evaluation of the quality of a food product and according to the Codex Alimentarius, limits should be set based on absolute criteria, according to legislation requirements or on relative criteria based on contamination trends over time within the production process The new European food hygiene regulations CE 852/04 e 2073/05 promote a more advanced and correct view of microbiological controls, with respect to pre-existing national legislation, placing emphasis also on the production process of foodstuffs and not only on the final product. In addition, controls are explicitly considered as a tool to verify that food business operators comply with hygiene requirements. The aim of evaluating microbiological data should be to assess trends in the various analytical parameters and search for possible contamination indicators, in order to perform a thorough analysis based on inspections that evaluate the efficacy of food safety procedures put in place by food business operators, with sampling aimed at verifying quick simple and low cost index parameters Regarding the interpretation of collected data it should be underscored that the presence of a large variability points to presence of inadequate hygiene procedures, considering that the main obligation of each food business operator is to put in place, implement and maintain procedures based on the HACCP principles. PMID:18936800

  8. 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

  9. Histories of Childhood Victimization and Subsequent Mental Health Problems, Substance Use, and Sexual Victimization for a Sample of Incarcerated Women in the US

    PubMed Central

    Tripodi, Stephen J.; Pettus-Davis, Carrie

    2012-01-01

    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 release 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 a child 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 womens trajectories to prison, which disproportionately includes childhood victimization and subsequent mental health and substance use problems. PMID:23196054

  10. 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 the proportion's format. A few unsuccessful participants lacked an understanding of basic algebraic procedures and of metric measurements. Even participants who had great difficulty solving medication-dosage calculation problems could expeditiously solve more complex problems if the medication used in the problem was well known to them.

  11. Preservice Secondary Mathematics Teachers' Modeling Strategies To Solve Problematic Subtraction and Addition Word Problems Involving Ordinal Numbers and Their Interpretations of Solutions.

    ERIC Educational Resources Information Center

    Contreras, Jose N.

    In this study I examined 19 preservice secondary mathematics teachers' solution processes to word problems for which the subtraction or addition of the two given numbers yields 1 more or 1 less than the correct solution. Among the aspects of their solution processes that were examined are: the modeling strategies, the type of errors, and the

  12. 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 techniques, such as radiation, be explored. While the purpose of this paper is not to design a sample return mission, the recommendations presented here are intended to act as guidelines for returning Martian samples in their pristine state. In essence, any procedure or piece of equipment that has the potential to compromise the pristinity of Martian samples during the collection, transportation, or curation needs to be fully evaluated by a scientific committee with the requisite expertise prior to implementation. CAPTEM is willing to serve in such a capacity if requested by NASA.

  13. 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)

  14. Genes involved in pruning and inflammation are enriched in a large mega-sample of patients affected by Schizophrenia and Bipolar Disorder and controls.

    PubMed

    Marco, Calabr; Antonio, Drago; Antonina, Sidoti; Alessandro, Serretti; Concetta, Crisafulli

    2015-08-30

    A molecular pathway analysis has been performed in order to complement previous genetic investigations on Schizophrenia. 4486 Schizophrenic patients and 4477 controls served as the investigation sample. 3521 Bipolar patients and 3195 controls served as replication sample. A molecular pathway associated with the neuronal pruning activity was found to be enriched in subjects with Schizophrenia compared to controls. HLA-C and HLA-DRA had more SNPs associated with both Schizophrenia and Bipolar Disorder than expected by chance. PMID:26160200

  15. 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

  16. Sarcoidosis with bone involvement mimicking metastatic disease at 18F-FDG PET/CT: problem solving by diffusion whole-body MRI

    PubMed Central

    Conte, Giorgio; Zugni, Fabio; Colleoni, Marco; Renne, Giuseppe; Bellomi, Massimo; Petralia, Giuseppe

    2015-01-01

    Bone involvement has been reported in 1–13% of patients with sarcoidosis. Both 18F-fluorodeoxyglucose (18F-FDG) Positron Emission Tomography/Computed Tomography (PET/CT) and conventional magnetic resonance imaging (MRI) are sensitive in detecting sarcoidosis bone lesions, but are not always reliable in differentiating sarcoidosis bone lesions from metastatic disease, thus often requiring bone biopsy. We describe the use of diffusion whole-body MRI for bone assessment in a patient with breast cancer and sarcoidosis, presenting with bone marrow lesions mimicking metastatic disease at 18F-FDG PET/CT. In our case, diffusion whole-body MRI represented a useful tool for bone assessment and overcame the limitation of 18F-FDG PET/CT in discriminating inflammatory bone marrow involvement from metastatic disease. PMID:26015806

  17. A literature review of medical side effects from radio-frequency energy in the human environment: involving cancer, tumors, and problems of the central nervous system.

    PubMed

    Jauchem, James R

    2003-01-01

    Occupational or residential exposures to radiofrequency energy (RFE), including microwaves, have been alleged to result in health problems. This paper is a review of the recent medical and scientific literature (from mid-1998 through 2002) dealing with possible effects of RFE on brain tumors and malignancies, leukemia, other cancers, and the central nervous system. A large number of studies were related to exposures from cellular telephones. On the basis of previous reviews of older literature and the current review of recent literature, one can conclude that the evidence for any proven health effects (related to the topics above) of low-level RFE exposure is minimal. PMID:15007865

  18. The Role of Negative Urgency and Expectancies in Problem Drinking and Disordered Eating: Testing a Model of Comorbidity in Pathological and At-Risk Samples

    PubMed Central

    Fischer, Sarah; Settles, Regan; Collins, Brittany; Gunn, Rachel; Smith, Gregory T.

    2013-01-01

    The aim of this study was to test hypotheses derived from a model that explains both the comorbidity of problem drinking and eating disorder symptoms and the difference in risk process between the two disorders. In Study One, the authors examined four personality constructs typically associated with rash action (sensation seeking, lack of planning, lack of persistence, and negative urgency) and disorder-specific expectancies in samples of women with eating disorders, substance dependence disorders, comorbid conditions, and no symptoms (N = 104). Negative urgency, the tendency to act rashly when distressed, differentiated the disordered groups from the control group. In contrast, learned expectancies differentiated among clinical groups. Women with eating disorders endorsed high levels of eating and dieting expectancies and women with substance use disorders endorsed high levels of alcohol expectancies, while comorbid women endorsed high levels of both. In Study Two, this pattern of findings was replicated in a sample of fifth grade girls (N = 905). Girls who had engaged in binge eating, alcohol use, or both had higher levels of negative urgency than asymptomatic girls, and the pattern of outcome expectancy endorsement was disorder specific. Negative urgency may represent a general, personality influence on both eating disordered behaviors and symptoms of alcohol dependence, which, when combined with learned, behavior-specific expectancies, leads to specific addictive behavior patterns. PMID:21604832

  19. 'They can't solve the problem without us': a qualitative study of stakeholder perspectives on user involvement in drug treatment services in England.

    PubMed

    Patterson, Sue; Weaver, Tim; Agath, Kostas; Albert, Eliot; Rhodes, Timothy; Rutter, Deborah; Crawford, Mike

    2009-02-01

    Providers of public health care are under pressure to involve service-users in service development. This pressure emanates from legislators and the public who promote user involvement (UI), as a 'means to an end' and/or 'an end in itself'. Case studies in six English commissioning areas explored the process and purpose of UI in drug treatment services. In-depth interviews with 139 respondents who commission, manage, deliver or use services were conducted. We identified 'non-', 'passive-' and 'active participant' users. Active users were commonly motivated by a desire for social justice, a social conscience and personal development. UI was evidently influenced by multiple social organizational and personal factors. Some 'generic' factors have been reported in other settings. However, the illegality of drug use powerfully affects all stakeholders creating a context unique to drug treatment settings. Stigma and power imbalances were pervasive, and strong tensions concerning the goal and purpose of UI were apparent. Within the UK context, we identified five organizational approaches to UI. Based on rationale and objectives of UI, and the scope of influence accorded users, organizations could be characterised as protagonists, pragmatists, sceptics, abstainers or avoiders. We conclude that many tensions apparent in local level UI have roots in UI policy, which is ambiguous about: (1) benefit and rights, and (2) the promotion of healthcare objectives within a UK drug strategy driven by a crime reduction agenda. This duality must be resolved for UI to flourish at local level. PMID:18564192

  20. Laser sampling

    NASA Astrophysics Data System (ADS)

    Gorbatenko, A. A.; Revina, E. I.

    2015-10-01

    The review is devoted to the major advances in laser sampling. The advantages and drawbacks of the technique are considered. Specific features of combinations of laser sampling with various instrumental analytical methods, primarily inductively coupled plasma mass spectrometry, are discussed. Examples of practical implementation of hybrid methods involving laser sampling as well as corresponding analytical characteristics are presented. The bibliography includes 78 references.

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

    PubMed

    Mir, Manuel; Hansen, Elo Harald

    2013-06-11

    Within the last decade, liquid-phase microextraction (LPME) and micro-solid phase extraction (?SPE) 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

  2. Adolescent Nonsexual and Sex-Related Problem Behaviors.

    ERIC Educational Resources Information Center

    Ketterlinus, Robert D.; And Others

    1992-01-01

    Compared the involvement in problem behaviors of a national sample of male and female youth who were: virgins, sexually experienced (never pregnant), pregnant, or parents. Regression analyses showed that never pregnant adolescents were more likely than virgins to have been involved in four types of nonsexual problem behaviors. (JBJ)

  3. 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 0.29,0.130.67 and 0.20,0.090.46), and 2 years (n?=?380[84%]) (aOR 0.68,0.500.93 and 0.55,0.281.09), and consent to infant blood sample donation (n?=?220[48%]) (aOR 0.72,0.570.92 and 0.43,0.220.83). 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%(0.913.1%) to 4.6%(?1.4+10.5%), and OR from 0.40(0.180.91) to 0.56(0.261.21). Other findings were unchanged. Conclusions Potential for volunteer bias intensified during the trial, due to non-participation of the most deprived and smokers. However, these were not the only predictors of non-participation. Data weighting quantified volunteer bias and modified one important trial outcome. Trial Registration This randomised, double blind, parallel group, placebo controlled trial is registered with the International Standard Randomised Controlled Trials Register, Number (ISRCTN) 26287422. Registered title: Probiotics in the prevention of atopy in infants and children. PMID:23874465

  4. 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

  5. Use of risk assessment instruments to predict violence and antisocial behaviour in 73 samples involving 24?827 people: systematic review and meta-analysis

    PubMed Central

    2012-01-01

    Objective To investigate the predictive validity of tools commonly used to assess the risk of violence, sexual, and criminal behaviour. Design Systematic review and tabular meta-analysis of replication studies following PRISMA guidelines. Data sources PsycINFO, Embase, Medline, and United States Criminal Justice Reference Service Abstracts. Review methods We included replication studies from 1 January 1995 to 1 January 2011 if they provided contingency data for the offending outcome that the tools were designed to predict. We calculated the diagnostic odds ratio, sensitivity, specificity, area under the curve, positive predictive value, negative predictive value, the number needed to detain to prevent one offence, as well as a novel performance indicatorthe number safely discharged. We investigated potential sources of heterogeneity using metaregression and subgroup analyses. Results Risk assessments were conducted on 73 samples comprising 24?847 participants from 13 countries, of whom 5879 (23.7%) offended over an average of 49.6 months. When used to predict violent offending, risk assessment tools produced low to moderate positive predictive values (median 41%, interquartile range 27-60%) and higher negative predictive values (91%, 81-95%), and a corresponding median number needed to detain of 2 (2-4) and number safely discharged of 10 (4-18). Instruments designed to predict violent offending performed better than those aimed at predicting sexual or general crime. Conclusions Although risk assessment tools are widely used in clinical and criminal justice settings, their predictive accuracy varies depending on how they are used. They seem to identify low risk individuals with high levels of accuracy, but their use as sole determinants of detention, sentencing, and release is not supported by the current evidence. Further research is needed to examine their contribution to treatment and management. PMID:22833604

  6. Adaptive Peer Sampling with Newscast

    NASA Astrophysics Data System (ADS)

    Tlgyesi, Norbert; Jelasity, Mrk

    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, namelywithout involving failure detectorsnodes 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.

  7. 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…

  8. 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

  9. The relationship of alcohol problems to the risk for unidirectional and bidirectional intimate partner violence among a sample of blue-collar couples.

    PubMed

    Cunradi, Carol B; Ames, Genevieve M; Duke, Michael

    2011-01-01

    Understanding how each partner's alcohol problems may contribute to the risk of male-to-female only, female-to-male only, or bidirectional partner violence is important for the prevention and treatment of these problems. Multinomial regression analysis was conducted using data from 848 blue-collar couples. Findings suggest that male alcohol problems are linked to male-to-female and bidirectional partner violence but not with female-to-male partner violence. Female alcohol problems do not appear to be related to any type of partner aggression. Each partner's level of impulsivity was associated with bidirectional partner violence. Male impulsivity was associated with male-to-female violence, and female impulsivity was associated with female-to-male violence. Prevention of male alcohol problems and promotion of nonconfrontational conflict-solving techniques may help reduce partner aggression among couples in the general household population. PMID:21780531

  10. Problems & Issues.

    ERIC Educational Resources Information Center

    Online-Offline, 2000

    2000-01-01

    Lists selected resources that help think about problems and issues and how they affect society in the areas of human health, social issues, and environmental issues. Includes Web sites, CD-ROMs and software, videos, books, magazines, and professional resources, with age levels and appropriate disciplines usually indicated. Suggests sample class

  11. Family Involvement.

    ERIC Educational Resources Information Center

    Liontos, Lynn Balster

    1992-01-01

    Family involvement in schools will work only when perceived as an enlarged concept focusing on all children, including those from at-risk families. Each publication reviewed here is specifically concerned with family involvement strategies concerned with all children or targeted at primarily high risk students. Susan McAllister Swap looks at three

  12. Community Involvement.

    ERIC Educational Resources Information Center

    Smith, Hayden R., Ed.

    1979-01-01

    This publication features thirteen articles on community involvement. Several programs and individuals concerned with the role of the community in educational development and improvement are discussed. The main points made in all of the articles are: 1) research on community involvement appears limited, and 2) research "experts" are grass roots

  13. 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.

    PubMed

    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 special schools for children with MMR in two municipalities in a region in the South-West of Sweden. The FTF is a 181-item parent questionnaire with age and gender specific Swedish norms covering eight domains, including the phenomenology of early symptomatic syndromes eliciting neurodevelopmental examinations (ESSENCE), including ADHD, autism, tic syndromes, and various kinds of language, memory, and learning problems. Parents of 63% (39/62) of the eligible target group completed the FTF. After scrutiny of the medical records, 6 of the 39 children were found not to meet criteria for MR. Scores exceeding the 90th centile of the norm group were considered indicative of neuropsychiatric problems. Such high scores are strongly associated with clinically valid ESSENCE/neuropsychiatric disorders. All the examined children with validated MR were reported by their parents to have learning problems. There were very high rates of problems reported in all the other seven FTF domains: perception (88%), language (79%), social skills/autism (76%), memory (67%), emotional problems (58%), motor skills (55%) and executive functions/ADHD (55%). School age children with MMR are all in need of a comprehensive work-up covering not only general cognitive abilities, but also many other areas, including motor skills, executive function/attention, social and emotional/behavioural symptoms/functioning. Such broad assessment (including child screening by parent report with the FTF) will enable a better basis for understanding their special needs of support through life. PMID:21703820

  14. Work Samples.

    ERIC Educational Resources Information Center

    Educational Testing Service, Princeton, NJ.

    Three work sample tasks--a logical contouring problem, a "pull-up" from an aerial photograph, and a geometric restitution task--for use in predicting job performance of the Cartographic Technician are provided. (For related documents, see TM 001 408, 463, 465, 466.) (DB)

  15. 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

  16. Educational Inequalities in the Co- occurrence of Mental Health and Substance Use Problems, and its Adult Socioeconomic Consequences: A Longitudinal Study of Young Adults in a Community Sample

    PubMed Central

    Lee, Jungeun Olivia; Herrenkohl, Todd I.; Kosterman, Rick; Small, Candice M.; Hawkins, J. David

    2013-01-01

    Objectives To examine the relationship between the co-occurrence of mental health and substance use problems and socioeconomic status (SES). Study design A prospective longitudinal study of 808 males and females followed to age 30. Methods Survey data were used to derive latent classes (profiles) of mental health (depression, anxiety) and substance use (alcohol, nicotine, and marijuana [cannabis]) problems at age 27. Analyses examined the associations of these profiles with earlier educational attainment (high school diploma) and indicators of SES at age 30. Results Latent Class Analysis produced four profiles: a low disorder symptoms group, a licit substance use disorder symptoms group (alcohol and nicotine), a mental health disorder symptoms group, and a comorbid group. Earning a high school diploma by age 21 decreased the odds of belonging to the comorbid group or the licit substance use disorder symptoms group when compared to the low disorder symptoms group. These disorder profiles also were found to adversely impact subsequent adult SES. The adverse impact was more evident in income maintenance and wealth accumulation by age 30 than market or nonmarket labor force participation. Conclusions Earning a high school diploma lessens the risk of co-occurring mental health and substance use problems which contribute to economic instability in young adulthood. Findings underscore the importance of public health programs to reduce the incidence of mental health and substance use problems and their associated high costs to individuals and to society. PMID:23870846

  17. 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…

  18. 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…

  19. 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

  20. Validation of the Alcohol Use Disorders Identification Test and the Drug Use Disorders Identification Test in a Swedish sample of suspected offenders with signs of mental health problems: results from the Mental Disorder, Substance Abuse and Crime study.

    PubMed

    Durbeej, Natalie; Berman, Anne H; Gumpert, Clara H; Palmstierna, Tom; Kristiansson, Marianne; Alm, Charlotte

    2010-12-01

    Substance abuse is common among offenders. One method widely used for the detection of substance abuse is screening. This study explored the concurrent validity of the Alcohol Use Disorders Identification Test (AUDIT) and the Drug Use Disorders Identification Test (DUDIT) screening tools in relation to (a) substance abuse and dependency diagnoses and (b) three problem severity domains of the sixth version of the Addiction Severity Index in a sample of 181 suspected offenders with signs of mental health problems. The screening tools showed moderate to high accuracy for identification of dependency diagnoses. The AUDIT was associated with alcohol problem severity, whereas the DUDIT was associated with drug and legal problem severity. Administering the screening tools in the current population yields valid results. However, the suggested cutoff scores should be applied with caution due to the discrepancy between present and previous findings. PMID:20822878

  1. Gender differences in the relationship between gambling problems and the incidence of substance-use disorders in a nationally representative population sample

    PubMed Central

    Pilver, Corey E.; Libby, Daniel J.; Hoff, Rani A.; Potenza, Marc N.

    2013-01-01

    Background Cross-sectional studies have demonstrated gender-related differences in the associations between problem-gambling severity and substance-use disorders; however, these associations have not been examined longitudinally. We aimed to examine the prospective associations between problem-gambling severity and incident substance-use disorders in women versus men. Methods Analyses were conducted using Wave-1 and Wave-2 NESARC data focusing on psychiatric diagnoses from 34,006 non-institutionalized US adults. Inclusionary criteria for pathological gambling were used to categorize Wave-1 participants as at-risk/problem gambling (ARPG) and non-ARPG (i.e. non-gambling/low-frequency gambling/low-risk gambling). Dependent variables included the three-year incidence of any substance-use disorder, alcohol-use disorders, nicotine dependence, drug-use disorders, prescription drug-use disorders, and illicit drug-use disorders. Results Significant gender-by-ARPG status interactions were observed with respect to the three-year incidence of nicotine dependence and prescription drug-use disorders, and approached significance with respect to incident alcohol-use disorders. ARPG (relative to non-ARPG) was positively associated with nicotine dependence among women (OR=2.00; 95% CI=1.24-3.00). ARPG was negatively associated with incident prescription drug-use disorders among men (OR=0.30; 95% CI=0.10-0.88)). Finally, ARPG was positively associated with incident alcohol-use disorders among men (OR=2.20; 95% CI=1.39-3.48). Conclusions Gambling problems were associated with an increased 3-year incidence of nicotine dependence in women and alcohol dependence in men. These findings highlight the importance of considering gender in prevention and treatment initiatives for adults who are experiencing gambling problems. Moreover, the specific factors underlying the differential progressions of specific substance-use disorders in women and men with ARPG warrant identification. PMID:23755930

  2. The Importance of Reference Gene Analysis of Formalin-Fixed, Paraffin-Embedded Samples from Sarcoma Patients An Often Underestimated Problem12

    PubMed Central

    Aggerholm-Pedersen, Ninna; Safwat, Akmal; Brentzen, Steen; Nordsmark, Marianne; Nielsen, Ole Steen; Alsner, Jan; Srensen, Brita S.

    2014-01-01

    Objective: Reverse transcription quantitative real-time polymerase chain reaction is efficient for quantification of gene expression, but the choice of reference genes is of paramount importance as it is essential for correct interpretation of data. This is complicated by the fact that the materials often available are routinely collected formalin-fixed, paraffin-embedded (FFPE) samples in which the mRNA is known to be highly degraded. The purpose of this study was to investigate 22 potential reference genes in sarcoma FFPE samples and to study the variation in expression level within different samples taken from the same tumor and between different histologic types. Methods: Twenty-nine patients treated for sarcoma were enrolled. The samples encompassed 82 (FFPE) specimens. Extraction of total RNA from 7-?m FFPE sections was performed using a fully automated, bead-base RNA isolation procedure, and 22 potential reference genes were analyzed by reverse transcription quantitative real-time polymerase chain reaction. The stability of the genes was analyzed by RealTime Statminer. The intrasamples variation and the interclass correlation coefficients were calculated. The linear regression model was used to calculate the degradation of the mRNA over time. Results: The quality of RNA was sufficient for analysis in 84% of the samples. Recommended reference genes differed with histologic types. However, PPIA, SF3A1, and MRPL19 were stably expressed regardless of the histologic type included. The variation in ?Cq value for samples from the same patients was similar to the variation between patients. It was possible to compensate for the time-dependent degradation of the mRNA when normalization was made using the selected reference genes. Conclusion: PPIA, SF3A1, and MRPL19 are suitable reference genes for normalization in gene expression studies of FFPE samples from sarcoma regardless of the histology. PMID:25500077

  3. 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

  4. Teacher Report of Children's Problem Behavior on The Sutter-Eyberg Student Behavior Inventory-Revised (SESBI-R) in a Norwegian Sample of Preschool and School Children

    ERIC Educational Resources Information Center

    Kirkhaug, Bente; Drugli, May Britt; Morch, Willy-Tore; Handegard, Bjorn Helge

    2012-01-01

    In the present study, the applicability of The Sutter-Eyberg Student Behavior Inventory-Revised (SESBI-R) was explored within a Norwegian sample of 983 children aged 3-8 years. By using an exploratory factor analysis the same 2-factor solution as the original SESBI-R was supported by Principal Component Analysis. Good internal consistency (alpha

  5. Parental Involvment.

    ERIC Educational Resources Information Center

    Mendoza, Jeanne; And Others

    This document presents one module in a set of training resources for trainers to use with parents and/or professionals serving children with disabilities; focus is on parental involvement. The modules stress content and activities that build skills and offer resources to promote parent-professional collaboration. Each module takes about 2 hours to

  6. Family Involvement.

    ERIC Educational Resources Information Center

    Nathanson, Jeanne H., Ed.

    1992-01-01

    This periodical issue focuses on the theme of involvement of families in the education of their children with disabilities. It includes papers with the following titles and authors: "A Message from the Assistant Secretary: Developing Successful Partnerships between Parents and Service Providers" (Robert R. Davila); "Parent Advocacy and Children

  7. 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

  8. 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

  9. 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

  10. Does the Association with Psychosomatic Health Problems Differ between Cyberbullying and Traditional Bullying?

    ERIC Educational Resources Information Center

    Beckman, Linda; Hagquist, Curt; Hellstrom, Lisa

    2012-01-01

    The association between mental health problems and traditional bullying is well known, whereas the strength of the association in cyberbullying is less known. This study aimed to compare the association between mutually exclusive groups of bullying involvement and psychosomatic problems as measured by the PsychoSomatic Problems scale. The sample

  11. Constructing Cooperative Logic Problems

    ERIC Educational Resources Information Center

    Munakata, Mika

    2005-01-01

    The complexities involved in writing mathematics problems and a cooperative learning activity that gives students the challenge of writing mathematical logic problems for their peers is discussed. Making students construct mathematics problems taps into several important skills in mathematics and students are asked to consider what it means to

  12. [The active contribution of the laboratory to the diagnosis and recovery of patients --resolution of sampling-related problems is important].

    PubMed

    Kataoka, Mika; Okamoto, Yasuyuki

    2009-02-01

    The objective of this symposium was to promote effective communication between medical doctors (MD) and medical technologists (MT) for efficient team-based medical treatment. We analyzed a model patient with disseminated intravascular coagulation (DIC) to demonstrate our strategy, primarily as clinical laboratory hematologists. To assess the response of the clinical central laboratory to severe septic DIC, questionnaires on the performance of laboratory tests for DIC at night were sent to the laboratories of six hospitals in the Nara area. Extra tests other than those fixed for the emergency room were carried out in many laboratories in response to requests from the doctors. This tendency was more marked in smaller sized laboratories; therefore, the level of communication was better in these smaller laboratories. Forty MTs filled out the questionnaires on the blood coagulation test and influence of sampling and others, especially pertaining to the night shift, and their responses were relatively favorable, but more active approaches and information were needed even if their subspecialty was not clinical hematology. In our cases of thrombotic thrombocytopenic purpura and May-Hegglin anomaly, active and specific laboratory-based participation contributes to the diagnosis and treatment. In conclusion, the most important point is that MTs and MDs show respect for each other and communicate cordially, because our final mutual goal is the recovery of the patient. PMID:19317223

  13. Reverse mapping of normal tissue complication probabilities onto dose volume histogram space: The problem of randomness of the dose volume histogram sampling

    SciTech Connect

    Markov, Krassimir; Schinkel, Colleen; Stavreva, Nadia; Stavrev, Pavel; Weldon, Michael; Fallone, B. Gino

    2006-09-15

    A very important issue in contemporary inverse treatment radiotherapy planning is the specification of proper dose-volume constraints limiting the treatment planning algorithm from delivering high doses to the normal tissue surrounding the tumor. Recently we have proposed a method called reverse mapping of normal tissue complication probabilities (NTCP) onto dose-volume histogram (DVH) space, which allows the calculation of appropriate biologically based dose-volume constraints to be used in the inverse treatment planning. The method of reverse mapping requires random sampling from the functional space of all monotonically decreasing functions in the unit square. We develop, in this paper, a random function generator for the purpose of the reverse mapping. Since the proposed generator is based on the theory of random walk, it is therefore designated in this work, as a random walk DVH generator. It is theoretically determined that the distribution of the number of monotonically decreasing functions passing through a point in the dose volume histogram space follows the hypergeometric distribution. The proposed random walk DVH generator thus simulates, in a random fashion, trajectories of monotonically decreasing functions (finite series) that are situated in the unit square [0,1]x[1,0] using the hypergeometric distribution. The DVH generator is an important tool in the study of reverse NTCP mapping for the calculation of biologically based dose-volume constraints for inverse treatment planning.

  14. 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 ...

  15. Sampling and Sample Preparation

    NASA Astrophysics Data System (ADS)

    Morawicki, Rubn 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.

  16. 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

  17. 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

  18. Mathematical Problem Solving.

    ERIC Educational Resources Information Center

    Mayer, Richard E.

    This chapter examines research on the cognitive processes involved in mathematical problem solving. The introduction includes definitions of key terms and a summary of four cognitive processes used in mathematical problem solving: (1) translating; (2) integrating; (3) planning; and (4) executing. Examples are then provided and exemplary research

  19. 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 ...

  20. 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 ...

  1. 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

  2. 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)

  3. 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)

  4. Age Trends in the Association between Parenting Practices and Conduct Problems.

    ERIC Educational Resources Information Center

    Frick, Paul J.; Christian, Rachel E.; Wootton, Jane M.

    1999-01-01

    Studies the association between parenting practices and conduct problem behavior in a sample (N=179) of children and adolescents. Results indicate that parents' involvement in their children's activities is most strongly predictive of conduct problems in the adolescent age group, whereas corporal punishment is most strongly associated with conduct

  5. Troubleshoot HRSG corrosion problems

    SciTech Connect

    Stanley, L.

    1996-07-01

    Heat-recovery steam generators (HRSGs) have come of age. At the same time, these boilers are more complex as designs are refined to maximize heat recovery. Hundreds of units are installed and now have years of operating experience providing valuable information that can benefit all HRSG owners. Experienced troubleshooters can anticipate potential problem areas and recommend cost-effective solutions. The HRSG corrosion problems summarized here--and the means by which they were identified and solved--are useful examples to alert other HRSG owners and operators to potential problem areas. Steps involved include thorough inspection and documentation, problem and cost/benefit analyses, and planning around outages.

  6. Problem drinkers and their problems

    PubMed Central

    Buchan, I. C.; Buckley, E. G.; Deacon, G. L. S.; Irvine, R.; Ryan, M. P.

    1981-01-01

    From general practice records of 9,763 patients, 106 problem drinkers were compared with a control group. The drinkers had a substantially higher number of problems and they consulted their doctor and attended casualty departments frequently. Social and marital problems were especially prevalent in the families of problem drinkers. PMID:7277292

  7. Nadaraya-Watson estimator for sensor fusion problems

    SciTech Connect

    Rao, N.S.V.

    1996-10-01

    The classical Nadaraya-Watson estimator is shown to solve a generic sensor fusion problem where the underlying sensor error densities are not known but a sample is available. By employing Haar kernels this estimator is shown to yield finite sample guarantees and also to be efficiently computable. Two simulation examples, and a robotics example involving the detection of a door using arrays of ultrasonic and infrared sensors, are presented to illustrate the performance.

  8. 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.

  9. Learning Problems

    MedlinePLUS

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Learning Problems KidsHealth > For Kids > Learning Problems Print A ... for how to make it better. What Are Learning Disabilities? Learning disabilities aren't contagious, but they ...

  10. 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 ...

  11. 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 ...

  12. 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 ...

  13. Solving Problems.

    ERIC Educational Resources Information Center

    Hale, Norman; Lindelow, John

    Chapter 12 in a volume on school leadership, this chapter cites the work of several authorities concerning problem-solving or decision-making techniques based on the belief that group problem-solving effort is preferable to individual effort. The first technique, force-field analysis, is described as a means of dissecting complex problems into

  14. Shoulder Problems

    MedlinePLUS

    ... adhesions can be highly effective in most cases. Fracture A fracture involves a partial or total crack through a ... a fall or blow to the shoulder. A fracture usually involves the clavicle or the neck (area ...

  15. 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.

  16. Multi-boson correlation sampling

    NASA Astrophysics Data System (ADS)

    Tamma, Vincenzo; Laibacher, Simon

    2015-11-01

    We give a full description of the problem of multi-boson correlation sampling (MBCS) at the output of a random interferometer for single input photons in arbitrary multi-mode pure states. The MBCS problem is the task of sampling at the interferometer output from the probability distribution associated with polarization- and time-resolved detections. We discuss the richness of the physics and the complexity of the MBCS problem for non-identical input photons. We also compare the MBCS problem with the standard boson sampling problem, where the input photons are assumed to be identical and the system is "classically" averaging over the detection times and polarizations.

  17. 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,

  18. Microbiological surface sampling cart

    NASA Technical Reports Server (NTRS)

    Wilkins, J. R.; Mills, S. M.

    1972-01-01

    Mobile sampling cart automatically swabs surfaces for the recovery of microorganisms. Unit operates without human involvement and provides for control of swabbing speed, rotation of cotton swab, and the pressure and angle applied to swab. Capability of reverse direction is also available. Sampling cart use is limited to flat surfaces.

  19. 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.

  20. 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

  1. 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

  2. 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

  3. Word Problems

    ERIC Educational Resources Information Center

    Fetrow, Jessica

    2009-01-01

    This study focused on how to help students translate word problems so that they understand how to solve them, and so they are successful with word problems. I have created three research questions to focus on during this research project. First, how will direct instruction of word meaning help clarify the operation needed, affect the achievement

  4. 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 ...

  5. Foot Problems

    MedlinePLUS

    ... thickened, or discolored toenails. Foot problems related to diabetes. Such as stubborn foot ulcers that are difficult to heal, loss of ... Older or obese people, women, and people with diabetes, cardiovascular ... have much higher rates of foot problems. For women, pain in the toes and ...

  6. Tooth Problems

    MedlinePLUS

    MENU Return to Web version Tooth Problems See complete list of charts. A tooth that causes ongoing pain may be a sign of a serious problem. Use ... you have an injury that knocked out a tooth? Yes You have TOOTH LOSS. DENTAL EMERGENCY See ...

  7. 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…

  8. 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

  9. 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

  10. 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…

  11. 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

  12. 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…

  13. 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…

  14. Teaching Problem Solving to College Students

    ERIC Educational Resources Information Center

    Malouff, John M.

    2011-01-01

    This article describes steps of teaching problem solving to college students and provides examples in the context of a university course. The steps involve (1) identifying the types of problems and types of problem solving methods to be covered, (2) instructing the students in problem-recognition and problem solving methods, along with ways of

  15. 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.

  16. Functional Assessment of Problem Behavior in Children with Autism Spectrum Disorders: A Summary of 32 Outpatient Cases

    ERIC Educational Resources Information Center

    Love, Jessa R.; Carr, James E.; LeBlanc, Linda A.

    2009-01-01

    The purpose of this study was to examine archival data from an outpatient clinic serving children with autism spectrum disorders to investigate the occurrence of problem behavior functions in this sample. Results indicated that social reinforcement (e.g., attention from others) was involved in maintaining problem behavior for the majority of

  17. 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 ...

  18. 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, ...

  19. 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 ...

  20. Vision problems

    MedlinePLUS

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

  1. Prostate Problems

    MedlinePLUS

    ... penis. Men with this problem often have painful ejaculation. They may feel the need to urinate frequently, ... in the back, hips, or pelvis, and painful ejaculation. To find out if these symptoms are caused ...

  2. Prostate Problems

    MedlinePLUS

    ... penis. Men with this problem often have painful ejaculation. They may feel the need to urinate 3 ... in the back, hips, or pelvis, and painful ejaculation. To find out if these symptoms are caused ...

  3. Erection problems

    MedlinePLUS

    ... Some peptic ulcer medications Other physical causes: Low testosterone levels: This can make it difficult to get ... conditions such as diabetes, heart problems, or low testosterone A device you wear at night to check ...

  4. Tongue problems

    MedlinePLUS

    ... drug that causes the tongue swelling. Seek medical attention right away if swelling is starting to make ... that helps? Are there problems with the teeth, gums, lips, or throat? Does the tongue bleed? Do ...

  5. Collecting Samples

    USGS Multimedia Gallery

    Collecting Samples at Embden 3. Embden 3 is a 60-degree V trapezoidal flume in a bured concreate culvert located on the other side of the north-south road east of the large data shelter. The flow is measured and sampled from the V flume underground and periodic QW grab samples are taken form the blu...

  6. 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 ...

  7. 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.

  8. A Sample of Sampling Definitions.

    ERIC Educational Resources Information Center

    Bobko, Philip; And Others

    1980-01-01

    Describes a study examing 34 introductory psychological statistics texts for their usage and definitions of the terms "random sample" and "simple random sampling." Results showed a high percentage of conceptual errors. (CK)

  9. 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.

  10. 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.

  11. 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

  12. PBINT, A Logic for Modelling Search Problems Involving Arithmetic

    NASA Astrophysics Data System (ADS)

    Tasharrofi, Shahab; Ternovska, Eugenia

    Motivated by computer science challenges, Grdel and Gurevich [13] suggested to extend the approach and methods of finite model theory beyond finite structures, an approach they called Metafinite Model Theory. We develop this direction further, in application to constraint specification/modelling languages. Following [27], we use a framework based on embedded model theory, but with a different background structure, the structure of arithmetic which contains at least (?; 0, 1, + , , < , || ||), where ||x|| returns the size of the binary encoding of x. We prove that on these structures, we can unconditionally capture NP using a variant of a guarded logic. This improves the result of [27] (and thus indirectly [13]) by eliminating the small cost condition on input structures.

  13. 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.

  14. Are accidents scheduled. [safety management problems

    NASA Technical Reports Server (NTRS)

    Childs, C.

    1976-01-01

    Two major sets of safety problems associated with project scheduling are examined. The first set involves problems resulting from the improper scheduling of the safety tasks. The second involves problems which result from inadequate attention to scheduling of those project tasks which lead to tests and operations and includes condensed schedules, modified schedules, schedule workarounds, eliminated portions of the schedules and strung out schedules.

  15. 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).

  16. Experiment Problems for Electricity and Magnetism.

    ERIC Educational Resources Information Center

    Van Heuvelen, Alan; Allen, Leith; Mihas, Pavlos

    1999-01-01

    Gives several sample experiment problems for electricity and magnetism. To solve an experiment problem, students have to do one or more of the following: clarify a poorly defined problem, divide a problem into parts, access the appropriate concept needed to solve each problem part, decide whether approximations are appropriate, design an

  17. Experiment Problems for Electricity and Magnetism.

    ERIC Educational Resources Information Center

    Van Heuvelen, Alan; Allen, Leith; Mihas, Pavlos

    1999-01-01

    Gives several sample experiment problems for electricity and magnetism. To solve an experiment problem, students have to do one or more of the following: clarify a poorly defined problem, divide a problem into parts, access the appropriate concept needed to solve each problem part, decide whether approximations are appropriate, design an…

  18. Hair Problems

    MedlinePLUS

    ... an inch. Most hairs grow for up to six years and then fall out. New hairs grow in their place. Hair helps keep you warm. It also protects your eyes, ears and nose from small particles in the air. Common problem with the hair and scalp include hair loss, infections, and flaking.

  19. 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)

  20. Routine Problems.

    ERIC Educational Resources Information Center

    Stein, Sherman

    1985-01-01

    A slight rewording can often transform a routine exercise into a nonroutine one. Three problems (with solutions) from first-year college calculus are presented to illustrate how the technique can be used and how it is applicable to any course. (JN)

  1. 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

  2. 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 79 (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 Sleep Med 2015;11(2):101110. PMID:25515273

  3. 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

  4. Lava Sampling

    USGS Multimedia Gallery

    An HVO geologist takes a sample of active lava within a lava tube. The fluid lava sticks to the heavy hammer head at the end of the cable when it is lowered into the swiftly moving lava stream. These samples are analyzed routinely to track changes in lava chemistry. ...

  5. SAMPLING ARTHROPODS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sampling is a fundamental process in most areas of experimentally-based research and is crucial for describing, measuring and quantifying arthropod population dynamics. This review attempts to provide a broadly-based, non-mathematical overview of sampling, including delineation of the goals of samp...

  6. 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…

  7. Environmental sampling

    SciTech Connect

    Puckett, J.M.

    1998-12-31

    Environmental Sampling (ES) is a technology option that can have application in transparency in nuclear nonproliferation. The basic process is to take a sample from the environment, e.g., soil, water, vegetation, or dust and debris from a surface, and through very careful sample preparation and analysis, determine the types, elemental concentration, and isotopic composition of actinides in the sample. The sample is prepared and the analysis performed in a clean chemistry laboratory (CCL). This ES capability is part of the IAEA Strengthened Safeguards System. Such a Laboratory is planned to be built by JAERI at Tokai and will give Japan an intrinsic ES capability. This paper presents options for the use of ES as a transparency measure for nuclear nonproliferation.

  8. 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…

  9. 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

  10. 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…

  11. Visualization and Arithmetic Problem Solving.

    ERIC Educational Resources Information Center

    Horwitz, Lucy

    One difficulty that mathematically naive subjects encounter in solving arithmetic word problems involves the limitation on short term memory (STM) capacity. It is hypothesized that naive subjects, not having access to formal problem solving strategies, may find visualization useful in reducing strain on STM. Two experiments are reported. The…

  12. 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 ...

  13. Hierarchi problem

    NASA Astrophysics Data System (ADS)

    Rubin, Sergey G.

    2016-02-01

    The way to solve the hierarchy problem based on multidimensional gravity is discussed. Various metrics of deformed extra space are produced at the Planck scale. It is shown that the Higgs vacuum value depends on a metric of extra space and hence their different numerical values are realized in various universes. An interval of the Higgs vacuum values is proved include zero value. Our universe belongs to a set of universes the vacuum values of which are close to zero

  14. 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…

  15. 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.…

  16. 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…

  17. Individualized Math Problems in Measurement and Conversion. 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 measurement, computation of…

  18. 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

  19. Individualized Math Problems in Measurement and Conversion. 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 measurement, computation of

  20. 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

  1. 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.

  2. 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

  3. 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…

  4. 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

  5. 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)

  6. Simulating Problem Solving and Classroom Settings

    ERIC Educational Resources Information Center

    Liedtke, Werner; Vance, James

    1978-01-01

    Some problems and classroom problem-solving settings presented in a mathematics methods course for elementary teachers are described and some results of student's involvement in the program are illustrated. (MN)

  7. 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)

  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. 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

  10. Design of sampling plans for mycotoxins in foods and feeds.

    PubMed

    Coker, R D; Nagler, M J; Blunden, G; Sharkey, A J; Defize, P R; Derksen, G B; Whitaker, T B

    1995-01-01

    The control of the occurrence of mycotoxins in foods and feeds requires effective surveillance and quality control procedures which facilitate the identification and control of the mycotoxin problem respectively. Surveillance and quality control procedures involve a sequence of sampling, sample preparation, and analysis steps; and the integrity of the data produced by these procedures will be determined by the effectiveness of these steps. It is imperative that the sampling step is performed as accurately as possible so that the sample collected is representative of the batch of food or feed under investigation. Needless to say, the collection of a biased sample will completely invalidate the resultant analytical data. Most attempts to develop effective sampling protocols have focused upon the aflatoxins, since the majority of current regulations are concerned specifically with this group of mycotoxins. However, the design of effective sampling protocols has been severely hindered by the highly skewed distribution of the aflatoxins in foods and feeds. Studies already performed indicate that representative samples of commodities, composed of large particles (e.g., corn and oilseed kernels) should be 10 kg in weight, at least, and composed of approximately one hundred incremental samples. Similar studies have indicated that samples of oilseed cakes and meal, however, should be composed of fifty incremental samples which afford a composite sample of approximately 5 kg in weight. PMID:7582626

  11. A new design of groundwater sampling device and its application.

    PubMed

    Tsai, Yih-jin; Kuo, Ming-ching T

    2005-01-01

    Compounds in the atmosphere contaminate samples of groundwater. An inexpensive and simple method for collecting groundwater samples is developed to prevent contamination when the background concentration of contaminants is high. This new design of groundwater sampling device involves a glass sampling bottle with a Teflon-lined valve at each end. A cleaned and dried sampling bottle was connected to a low flow-rate peristaltic pump with Teflon tubing and was filled with water. No headspace volume was remained in the sampling bottle. The sample bottle was then packed in a PVC bag to prevent the target component from infiltrating into the water sample through the valves. In this study, groundwater was sampled at six wells using both the conventional method and the improved method. The analysis of trichlorofluoromethane (CFC-11) concentrations at these six wells indicates that all the groundwater samples obtained by the conventional sampling method were contaminated by CFC-11 from the atmosphere. The improved sampling method greatly eliminated the problems of contamination, preservation and quantitative analysis of natural water. PMID:16313014

  12. 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.

  13. Sampling apparatus

    DOEpatents

    Gordon, Norman R. (Kennewick, WA); King, Lloyd L. (Benton, WA); Jackson, Peter O. (Richland, WA); Zulich, Alan W. (Bel Air, MD)

    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.

  14. 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

  15. 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

  16. Inverting a Triangular Array: Involving Students in Mathematical Inquiry

    ERIC Educational Resources Information Center

    Baroody, Arthur J.; Wilkins, Jesse L. M.

    2004-01-01

    Fostering students' mathematical thinking requires regularly presenting them with challenging problems and involving them in the processes of mathematical inquiry (e.g., representing and solving problems; making, testing, and justifying conjectures). The Inverting a 36 Penny Triangular Array problem (called the Inverting problem, for short) is a

  17. 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

  18. Curriculum and Community Involvement

    ERIC Educational Resources Information Center

    Feldmann, Doug

    2006-01-01

    Historically, the consolidation of school districts has brought with it many promises and perils. In this paper, the author links curriculum and community involvement within the consolidation context.

  19. Sample Containers

    USGS Multimedia Gallery

    On April 20, 2010, the Deepwater Horizon Drilling Platform exploded and sank, causing an enormous oil spill in the Gulf of Mexico. U.S. Geological Survey field offices responded immediately by organizing teams to take pre-spill sediment and water samples in order to establish a baseline survey. This...

  20. Water Sampling

    USGS Multimedia Gallery

    On April 20, 2010, the Deepwater Horizon Drilling Platform exploded and sank, causing an enormous oil spill in the Gulf of Mexico. U.S. Geological Survey field offices responded immediately by organizing teams to take pre-spill sediment and water samples in order to establish a baseline survey. This...

  1. Sand Sampling

    USGS Multimedia Gallery

    On April 20, 2010, the Deepwater Horizon Drilling Platform exploded and sank, causing an enormous oil spill in the Gulf of Mexico. U.S. Geological Survey field offices responded immediately by organizing teams to take pre-spill sediment and water samples in order to establish a baseline survey. This...

  2. Games and gambling involvement among casino patrons.

    PubMed

    LaPlante, Debi A; Afifi, Tracie O; Shaffer, Howard J

    2013-06-01

    A growing literature is addressing the nature of the relationships among gambling activity, gambling involvement, and gambling-related problems. This research suggests that among the general population, compared to playing any specific game, gambling involvement is a better predictor of gambling-related problems. To date, researchers have not examined these relationships among casino patrons, a population that differs from the general population in a variety of important ways. A survey of 1160 casino patrons at two Las Vegas resort casinos allowed us to determine relationships between the games that patrons played during the 12 months before their casino visit, the games that patrons played during their casino visit, and patrons' self-perceived history of gambling-related problems. Results indicate that playing specific gambling games onsite predicted (i.e., statistically significant odds ratios ranging from .5 to 4.51) self-perceived gambling-related problems. However, after controlling for involvement, operationally defined as the number of games played during the current casino visit and self-reported gambling frequency during the past 12 months, the relationships between games and gambling-related problems disappeared or were attenuated (i.e., odds ratios no longer statistically significant). These results extend the burgeoning literature related to gambling involvement and its relationship to gambling-related problems. PMID:22581196

  3. 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...

  4. Sports Participation and Problem Alcohol Use

    PubMed Central

    Mays, Darren; DePadilla, Lara; Thompson, Nancy J.; Kushner, Howard I.; Windle, Michael

    2014-01-01

    Background Sports participation, though offering numerous developmental benefits for youths, has been associated with adolescent alcohol use. Differences also exist between men/boys and women/girls in both sports participation and patterns of alcohol-related behaviors, but there are few longitudinal investigations of this relationship. Purpose This study investigated the relationship between school-based sports participation and alcohol-related behaviors using data from a multiwave national study of adolescent men/boys and women/girls. Methods Nationally representative data from the National Longitudinal Study of Adolescent Health, collected between 1994 and 2001, were analyzed in 2009 (n = 8271). Latent growth modeling, accommodating the complex sampling design, was applied to examine whether participation in school-based sports was associated with initial levels and change in problem alcohol use over three waves of data collection. Results After taking into account time-invariant covariates including demographics and other predictors of alcohol use, greater involvement in sports during adolescence was associated with faster average acceleration in problem alcohol use over time among youths who took part in only sports. The findings suggest, however, that the relationship between sports participation and problem alcohol use depends on participation in sports in combination with other activities, but it does not differ between men/boys and women/girls. Conclusions Sports may represent an important and efficient context for selective interventions to prevent problem alcohol use and negative consequences of alcohol use among adolescents. PMID:20409498

  5. Involving the Community.

    ERIC Educational Resources Information Center

    Jardine, Douglas K.

    When a college is held in high esteem by the important and prominent leaders in the larger community, that community can be counted on in times of need or crisis. Therefore, community involvement, though clearly a high moral imperative, also grows out of the college's enlightened self-interest. In an effort to increase involvement in and with the

  6. [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"…

  7. 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

  8. 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 e?cient 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/.

  9. Problem Solving with the Elementary Youngster.

    ERIC Educational Resources Information Center

    Swartz, Vicki

    This paper explores research on problem solving and suggests a problem-solving approach to elementary school social studies, using a culture study of the ancient Egyptians and King Tut as a sample unit. The premise is that problem solving is particularly effective in dealing with problems which do not have one simple and correct answer but rather

  10. 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

  11. Problem Solving with the Elementary Youngster.

    ERIC Educational Resources Information Center

    Swartz, Vicki

    This paper explores research on problem solving and suggests a problem-solving approach to elementary school social studies, using a culture study of the ancient Egyptians and King Tut as a sample unit. The premise is that problem solving is particularly effective in dealing with problems which do not have one simple and correct answer but rather…

  12. 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

  13. 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.

  14. Psychosocial characteristics of alcohol-involved and nonalcohol-involved seriously injured drivers.

    PubMed

    Vingilis, E; Stoduto, G; Macartney-Filgate, M S; Liban, C B; McLellan, B A

    1994-04-01

    This study compared two groups of alcohol-positive and alcohol-negative, seriously injured, crash-involved drivers on demographics, personality characteristics, driving-related attitudes, prior driving history, lifestyle, substance use, and antecedent driver condition. The study sample was drawn from motor vehicle accident admissions to the Sunnybrook Health Science Centre Regional Trauma Unit. One hundred and six interviews were completed between August 1986 and November 1989, with blood alcohol concentration (BAC) data available for 96 drivers. These data suggest no driving-related attitude differences between the two groups. Self-reported driving histories indicated significantly fewer graduates of driving schools and more licence suspensions for the BAC-positive group. The only consistently significant differences were found for the drinking-related variables, with a greater percentage of the BAC-positive group reporting: lower age of first intoxication; a greater self-perceived drinking problem; a greater frequency of intoxication in the month before the accident; and greater self-reported drinking-driving in the month before the accident. Principal-components factor analysis revealed a four-factor solution labelled: Alcohol Use, Deviant/Illicit Drug Use, Aggression, and Neuroticism. Alcohol Use was the only factor found to contribute substantially to the discriminant function, together with the job-related stress item. These data suggest that seriously injured, alcohol-positive and alcohol-negative crashed drivers are similar except that the alcohol-positive drivers show more signs of an alcohol problem. PMID:8198688

  15. 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

  16. 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.

  17. Eye Involvement in TSC

    MedlinePLUS

    ... List Sign Up TSC Clinics CME Opportunities TS Alliance Grants Program Other TSC Funding Opportunities TSC Alert ... and any possible involvement in TSC. **Tuberous Sclerosis Alliance Information Sheets are intended to provide basic information ...

  18. 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 ...

  19. 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

  20. 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

  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. Remote gas sampling with a swirl air stream.

    PubMed

    Kolomiets, Yuri N; Pervukhin, Viktor V

    2010-04-15

    One of the promising techniques of remote gas sampling from the surface or from the inside of an object involves the use of a swirl air stream. The case in which a swirl sampling stream produces a vortex core of a composite swirl is of most interest. But a practical implementation of a vortex sampling faces major problems due to the fact that the majority of the available gas analyzers feature a low analytical flow. This offers limitations on sampling distance and reduced pressure created at the object surface. This paper deals with the problem of adjusting vortex and sampling flows for a mass-spectrometer with atmospheric pressure ionization used for remote sampling of diethylanyline vapors. It is shown experimentally that additional sampling flow (Q(add)) that coaxially envelops an analytical channel allows one to achieve conditions required for the formation of a vortex core, which is characterized by an increased tangential component of the flow velocity at its boundary and abnormally low pressure on the core axis. A satisfactory agreement between the calculations by the composite vortex model and the experiment is obtained. The studies performed have shown that the optimal relationship between vortex (Q(vortex)) and additional flows is Q(vortex)/Q(add)=1.3 and is symbate in terms of both gas dynamic parameters (minimal diameter of a backflow core) and sampling efficiency. It is shown that both the sampling distance and sampling area depend mainly on geometric sampler parameters. The experiments performed have revealed the unique ability of a vortex sampling flow in the form of a composite vortex to focus the sample inside the vortex core, thus preventing its dilution over the backflow. PMID:20188922

  3. 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.

  4. 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.

  5. 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…

  6. Problem-Solving Errors of Educational Leaders.

    ERIC Educational Resources Information Center

    Hart, Ann W.; And Others

    Problem solving is one of the most important skills that new and developing professionals must learn. The process is complex, involving information scanning, problem identification, and feedback processes requiring synthesis, interim assessments, problem error recognition and rectification, and timely and appropriate conclusions. This study used

  7. 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.

  8. Image correlation and sampling study

    NASA Technical Reports Server (NTRS)

    Popp, D. J.; Mccormack, D. S.; Sedwick, J. L.

    1972-01-01

    The development of analytical approaches for solving image correlation and image sampling of multispectral data is discussed. Relevant multispectral image statistics which are applicable to image correlation and sampling are identified. The general image statistics include intensity mean, variance, amplitude histogram, power spectral density function, and autocorrelation function. The translation problem associated with digital image registration and the analytical means for comparing commonly used correlation techniques are considered. General expressions for determining the reconstruction error for specific image sampling strategies are developed.

  9. Optical chromatographic sample fractionation

    NASA Astrophysics Data System (ADS)

    Terray, Alex; Taylor, Joseph D.; Hart, Sean J.

    2009-08-01

    Optical Chromatography involves the elegant combination of opposing optical and fluid drag forces on colloidal samples within microfluidic environments to both measure analytical differences and fractionate injected samples. Particles that encounter the focused laser beam are trapped axially along the beam and are pushed upstream from the laser focal point to rest at a point where the optical and fluid forces on the particle balance. In our recent devices particles are pushed into a region of lower microfluidic flow, where they can be retained and fractionated. Because optical and fluid forces are sensitive to differences in the physical and chemical properties of a sample, differences between samples and thus separations are possible. An optical chromatography beam focused to completely fill a fluid channel is operated as an optically tunable filter for the separation of polymeric/colloidal and biological samples. We demonstrate this technique coupled with an advanced microfluidic platform and show how it can be used as an effective method to fractionate particles in an injected multi-component sample. Our advanced microfluidic design accommodates three lasers simultaneously to effectively create a sequential cascade optical chromatographic separation system.

  10. Sparse grid collocation schemes for stochastic natural convection problems

    SciTech Connect

    Ganapathysubramanian, Baskar; Zabaras, Nicholas . E-mail: zabaras@cornell.edu

    2007-07-01

    In recent years, there has been an interest in analyzing and quantifying the effects of random inputs in the solution of partial differential equations that describe thermal and fluid flow problems. Spectral stochastic methods and Monte-Carlo based sampling methods are two approaches that have been used to analyze these problems. As the complexity of the problem or the number of random variables involved in describing the input uncertainties increases, these approaches become highly impractical from implementation and convergence points-of-view. This is especially true in the context of realistic thermal flow problems, where uncertainties in the topology of the boundary domain, boundary flux conditions and heterogeneous physical properties usually require high-dimensional random descriptors. The sparse grid collocation method based on the Smolyak algorithm offers a viable alternate method for solving high-dimensional stochastic partial differential equations. An extension of the collocation approach to include adaptive refinement in important stochastic dimensions is utilized to further reduce the numerical effort necessary for simulation. We show case the collocation based approach to efficiently solve natural convection problems involving large stochastic dimensions. Equilibrium jumps occurring due to surface roughness and heterogeneous porosity are captured. Comparison of the present method with the generalized polynomial chaos expansion and Monte-Carlo methods are made.

  11. Assessment of gastrointestinal involvement.

    PubMed

    Clements, P J; Becvar, R; Drosos, A A; Ghattas, L; Gabrielli, A

    2003-01-01

    The purpose of this paper is to identify a list of clinical, laboratory and instrumental tools suitable to assess the presence of gastrointestinal involvement in SSc patients to be included in clinical investigational studies. The pertinent literature was reviewed to select those variables which have been demonstrated to be valid, reliable and feasible. A minimal core set of variables has been identified to be used in clinical investigation for the assessment of esophagus, stomach, small intestine, colon and anorectum involvement in scleroderma patients. PMID:12889216

  12. Multigrid method for stability problems

    NASA Technical Reports Server (NTRS)

    Ta'asan, Shlomo

    1988-01-01

    The problem of calculating the stability of steady state solutions of differential equations is addressed. Leading eigenvalues of large matrices that arise from discretization are calculated, and an efficient multigrid method for solving these problems is presented. The resulting grid functions are used as initial approximations for appropriate eigenvalue problems. The method employs local relaxation on all levels together with a global change on the coarsest level only, which is designed to separate the different eigenfunctions as well as to update their corresponding eigenvalues. Coarsening is done using the FAS formulation in a nonstandard way in which the right-hand side of the coarse grid equations involves unknown parameters to be solved on the coarse grid. This leads to a new multigrid method for calculating the eigenvalues of symmetric problems. Numerical experiments with a model problem are presented which demonstrate the effectiveness of the method.

  13. Parent Involvement. Research Brief

    ERIC Educational Resources Information Center

    Walker, Karen

    2007-01-01

    What are some ways in which to get parents meaningfully involved in their child's high school? According to the research, the most successful programs are those that provide a variety of ways in which parents can be actively engaged in their child's academic life. Joyce Epstein, Director of the National Network of Partnership Schools, out of Johns

  14. The Impact of Involvement.

    ERIC Educational Resources Information Center

    Jao, Greg

    1988-01-01

    Discusses the experiences associated with being involved in scholastic journalism and in researching the book "Voice of Conflict and Voices of Hope." Finds the value of scholastic journalism lies in its potential to train reporters and editors to seek the hidden experiences of student life that the "professional" media cannot investigate. (JK)

  15. [Cardiac involvement in polymyositis].

    PubMed

    Romdhane, M B; Mahdhaoui, A; Khelifa, M B; Lagren, A; Hajri, S E; Bouraoui, H; Trimeche, B; Ghannouchi, N; Jeridi, G; Bahri, F

    2012-08-01

    Cardiovascular involvement in polymyositis constitutes a major cause of death. However, the cardiac location is rarely symptomatic and does not usually represent the principle clinical feature at the time of the initial presentation. We present here an unusual case of polymyositis with severe and polymorph cardiac disturbances that predominant the muscular signs. PMID:20709312

  16. Encouraging Increased Employer Involvement.

    ERIC Educational Resources Information Center

    Lewis, Morgan V.

    1983-01-01

    Discusses major forces that are likely to increase the involvement of employers in the preparation of young people for employment, including international economic competition, technological innovation, and demographic shifts. Based on these influences, presents a new model of employer participation in order to develop a skilled work force. (W.C.

  17. Adolescent Involvement in Discipline Decision Making

    ERIC Educational Resources Information Center

    Deroma, Virginia M.; Lassiter, Kerry S.; Davis, Virginia A.

    2004-01-01

    This study examined the influence of (a) low, medium, or high adolescent involvement (degree to which adolescent input was solicited in determining consequence) in discipline decisions and (b) parental versus adolescent focus of impact of behavior problem (parent emphasized inconvenience to either self or adolescent). After viewing videotaped…

  18. 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

  19. Family Problems and Youth Unemployment.

    ERIC Educational Resources Information Center

    de Goede, Martijn; Spruijt, Ed; Maas, Cora; Duindam, Vincent

    2000-01-01

    Examines how family and personal characteristics relate to the employment situation of adolescents (N=995) in Denmark. Results show that parental divorce, parental unemployment (only for males), low parental affective involvement, and adolescent relationship problems were related to youth unemployment, but educational career and work commitment…

  20. 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

  1. 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.

  2. Relationships with Adults as Predictors of Substance Use, Gang Involvement, and Threats to Safety among Disadvantaged Urban High-School Adolescents

    ERIC Educational Resources Information Center

    Ryan, Linda G.; Miller-Loessi, Karen; Nieri, Tanya

    2007-01-01

    Using a resilience framework, the authors examined the protective effects of parental support, self-disclosure to parents, parent-initiated monitoring of adolescent behavior, and relationships with school personnel on three critical problems of adolescents: substance use, gang involvement, and perceived threats to safety at school. The sample

  3. 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.

  4. 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

  5. Estimation problems in rainfall modeling

    NASA Astrophysics Data System (ADS)

    Krajewski, Witold F.; Georgakakos, Konstantine P.

    A special session entitled Estimation Problems in Rainfall Modeling was held during the 1985 AGU Fall Meeting in San Francisco, Calif. The session was chaired by Witold F. Krajewski of the Hydrologic Research Laboratory of the National Weather Service (NWS), Silver Spring, Md. The purpose of the session was to bring together researchers interested in a wide range of rainfall-related estimation problems, such as parameter estimation, state estimation, multiple sensor rainfall analysis, and estimation problems in rainfall simulation. The topics of papers presented at the session included parameter estimation of point process models, errors in radar rainfall observations, and sampling aspects of space-state representation of rainfall.

  6. Multigrid method for stability problems

    NASA Technical Reports Server (NTRS)

    Taasan, Shlomo

    1988-01-01

    The problem of calculating the stability of steady state solutions of differential equations is treated. Leading eigenvalues (i.e., having maximal real part) of large matrices that arise from discretization are to be calculated. An efficient multigrid method for solving these problems is presented. The method begins by obtaining an initial approximation for the dominant subspace on a coarse level using a damped Jacobi relaxation. This proceeds until enough accuracy for the dominant subspace has been obtained. The resulting grid functions are then used as an initial approximation for appropriate eigenvalue problems. These problems are being solved first on coarse levels, followed by refinement until a desired accuracy for the eigenvalues has been achieved. The method employs local relaxation on all levels together with a global change on the coarsest level only, which is designed to separate the different eigenfunctions as well as to update their corresponding eigenvalues. Coarsening is done using the FAS formulation in a non-standard way in which the right hand side of the coarse grid equations involves unknown parameters to be solved for on the coarse grid. This in particular leads to a new multigrid method for calculating the eigenvalues of symmetric problems. Numerical experiments with a model problem demonstrate the effectiveness of the method proposed. Using an FMG algorithm a solution to the level of discretization errors is obtained in just a few work units (less than 10), where a work unit is the work involved in one Jacobi relization on the finest level.

  7. AUTOMATED STORM WATER SAMPLING ON SMALL WATERHSEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Typical automated storm sampling involves setting a minimum threshold to initiate sampling and setting a time or flow interval on which to collect samples after the sampler is triggered. However, little guidance is currently available to assist in making these settings for storm sampling strategies...

  8. 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 endometriosiss 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

  9. Deaths involving serotonergic drugs.

    PubMed

    Pilgrim, J L; Gerostamoulos, D; Drummer, Olaf H

    2010-05-20

    Serotonin-active drugs are detected relatively frequently in Victorian deaths. During 2002-2008, there were 1123 fatalities where one or more of the serotonin-active drugs tramadol, venlafaxine, fluoxetine, sertraline, citalopram, paroxetine and MDMA, were detected. These deaths were reviewed using pathology, toxicology and police reports, to determine the contribution of these drugs to the cause of death, particularly if serotonin toxicity was the mechanism of death. There were 28 cases of most interest to this research because of the presence of the target drugs and the circumstances suggesting the likelihood of serotonin toxicity involvement in death. There were 5 cases of reported serotonin toxicity and 23 other deaths suspected to have involved this form of toxicity. Tramadol featured most commonly out of the seven target drugs and was frequently detected in combination with serotonergic antidepressants. MDMA was also detected relatively commonly and was associated with moclobemide in 4 cases of confirmed serotonin toxicity. There were an additional 1095 cases where natural disease, external injury or the misuse of other drugs caused death, of which 2 reported the incidental contribution of serotonin toxicity. PMID:20172668

  10. 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

  11. Sleep promotes analogical transfer in problem solving.

    PubMed

    Monaghan, Padraic; Sio, Ut Na; Lau, Sum Wai; Woo, Hoi Kei; Linkenauger, Sally A; Ormerod, Thomas C

    2015-10-01

    Analogical problem solving requires using a known solution from one problem to apply to a related problem. Sleep is known to have profound effects on memory and information restructuring, and so we tested whether sleep promoted such analogical transfer, determining whether improvement was due to subjective memory for problems, subjective recognition of similarity across related problems, or by abstract generalisation of structure. In Experiment 1, participants were exposed to a set of source problems. Then, after a 12-h period involving sleep or wake, they attempted target problems structurally related to the source problems but with different surface features. Experiment 2 controlled for time of day effects by testing participants either in the morning or the evening. Sleep improved analogical transfer, but effects were not due to improvements in subjective memory or similarity recognition, but rather effects of structural generalisation across problems. PMID:26113445

  12. 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…

  13. 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.

  14. 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.

  15. When Is a Problem Not a Problem?

    ERIC Educational Resources Information Center

    Gough, John

    1997-01-01

    Finds that many activities that have been called "problems" are merely exercises or tricks. Offers a clearer definition of the word "problem". Notes some of the classroom implications of the new insight. (Author/CCM)

  16. Sleep problems in individuals with Angelman syndrome.

    PubMed

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

    2004-07-01

    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 significant associations were found between presence of a severe sleep problem and other variables (e.g., epilepsy, age, living environment, cause of genetic disorder, parents' and caregivers' coping strategies). Most parents reported adverse effects of their child's sleep problems on their own well-being. Implications for analysis and treatment of sleep problems in individuals with Angelman syndrome are discussed. PMID:15176919

  17. 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

  18. [Cardiac involvement in dystrophinopathies].

    PubMed

    Wahbi, K

    2015-12-01

    Dystrophinopathies may be associated with dilated cardiomyopathy, characterized by an impairment of left ventricular ejection fraction and potentially complicated by clinical heart failure. Conduction system disease and supraventricular or ventricular arrhythmias may also be present. The prevalence of cardiomyopathy is extremely high in Duchenne muscular dystrophy, intermediate in Becker dystrophy, and lower in female carriers. Cardiac follow-up is indicated in any patient with a mutation in the dystrophin gene, based on electrocardiogram and echocardiography, and must be closer, at least on a yearly basis, in patients with the highest cardiac risk. Systematic cardiac workups allow an earlier diagnosis of cardiac involvement and a prompt treatment. First-line treatments are angiotensin-converting-enzyme inhibitors and other heart failure treatments, which must be systematically initiated at the age of 10 years or earlier in Duchenne muscular dystrophy and regarding the identification of cardiac abnormalities in any patient with other dystrophinopathies. PMID:26773585

  19. Aluminium Involvement in Neurotoxicity

    PubMed Central

    Fulgenzi, Alessandro; Vietti, Daniele; Ferrero, Maria Elena

    2014-01-01

    The aetiology of neurodegenerative diseases (ND) seems to involve susceptibility genes and environmental factors. Toxic metals are considered major environmental pollutants. Following our study of a case of multiple sclerosis (MS) improvement due to removal of aluminium (Al) and other toxic metals, we have examined the possible relationship between Al intoxication and ND. We used the slow intravenous treatment with the chelating agent EDTA (calcium disodium ethylene diamine tetraacetic acid) (chelation test) to remove Al and detected it in the urine collected from the patients for 12 hours. Patients affected by MS represented 85.6% of total ND. Al was present in 44.8% of cases comprehensive of ND and healthy patients. Al levels were significantly higher in ND patients than in healthy subjects. We here show that treatment of patients affected by Al burden with ten EDTA chelation therapies (EDTA intravenous administration once a week) was able to significantly reduce Al intoxication. PMID:25243176

  20. 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 SN2 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

  1. Employer Involvement in Georgia Youth Apprenticeship Programs.

    ERIC Educational Resources Information Center

    Smith, Clifton

    1996-01-01

    A study was conducted to provide insight into employer participation in Georgia youth apprenticeship programs that offer work experience and learning at the work site. Data were gathered through a survey sent to a random sample of 206 employers, of the 450 employers involved in youth apprenticeship programs in the state. Analysis of the 121

  2. An expert sample analysis planner

    SciTech Connect

    Spencer, W.A.; Parks, W.S.

    1990-01-01

    Analytical chemists are faced with the problem of choosing an appropriate analytical technique for a particular sample and weighing the options as they affect precision, time, and cost. This paper describes a computer technique to assist managers in reviewing the alternatives and to match needs with the resources available. This paper proposes an expert system, knowledgeable of analytical chemistry techniques, to create sample plans. Sample planning is an appropriate topic for expert systems because scarce human expertise is required to complete sample plans. A sample plan is the description of how samples received at the Savannah River Laboratory are handled, controlled, measured, and dispositioned. Sample planning is difficult because multiple experts are needed, planning is not a static function, and planning is time consuming. An Expert Sample Analyses Planner (XSAP) is proposed to create sample plans for laboratory managers. XSAP supplements the scarce knowledge of analytical techniques creating sample plans based on analysis constraints, methods available, and time requirements. XSAP interacts with the chemist to suggest sample plans. XSAP considers equipment available locally, at other Savannah River laboratories, at other Department of Energy facilities, and at other commercial laboratories. XSAP allows options on scheduling: best solution, cheapest solution, best local solution, and fastest solution. 26 refs.

  3. Operators tackle Anadarko cementing problems

    SciTech Connect

    Spradlin, W.N.

    1983-06-01

    Successful cementing in the deep Anadarko Basin, as in other deep producing provinces, requires meticulous attention to detail. Problems encountered during cementing operations include high temperature, high pressure, gas migration, and lost circulation. At times, these problems stretch the bounds of technology in rheological control of drilling mud and cement slurry. Although successful cementing techniques for Anadarko Basin deep wells present particular challenges, the principles involved also apply to other deep producing provinces. Deep well programs vary from one area of the Anadarko Basin to another. The variation is a function of the pressure encountered while drilling.

  4. SST Sample Characterization Analysis of Archive Samples 102-C, 105-C, and 106-C

    SciTech Connect

    Hara, F. T.; Kaye, J. H.; Steele, R. T.; Stromatt, R. W.; Thomas, D. L.; Urie, M. W.

    1990-04-01

    A substantial effort is planned to be initiated at the Hanford Site regarding the characterization of 149 single-shell tanks (SSTs) containing the byproducts of reprocessing during the 1950s and 1960s. Sampling and analysis, in distinct phases, are planned to involve laboratory investigations to determine both chemical and radionuclide inventories, so that waste disposal decisions can be developed. During 1989, trial analyses were performed on four archived samples from SSTs at the Pacific Northwest Laboratory using established U.S. Environmental Protection Agency (EPA) protocols and radiochemical procedures. The analysis of the archived SST waste material provides three important types of data for use in planning Phase I-A and Phase 1-B sample analysis. The types of data served as input to I) fi na 1 i zing the waste samp 1 e analysis procedures and methods and identify where procedure developmen~ may be needed, 2) evaluating the impact of normal paraffin hydrocarbon (NPH) lubricant {used in field sampling) on extracting inorganics or radionuclides from the SST sample, and 3) identifying trends in amounts of occupational radiation exposure expected from performing the various analysis procedures. Overall, the results are qualitative in nature, and the conclusions given are to be used with appropriate respect for the limitations of small amounts of data from four samples used in development processes. The results of the Phase I-A and I-B sample analysis will provide essential data for method performance for use in finalizing Phase I-C planning and methods development scope. Section 2.0, Inorganic Analysis, encompasses sample preparation, sample analysis, identification of methods performance limitations, and possible alternatives. Performance of the inorganic analytical methods was evaluated and changes were made to some of the procedures. In some cases, inductively coupled plasma-atomic emission spectroscopy (referred to in this report as ICP) did not provide the levels of accuracy and precision usually required for EPA work due to interference by other elements. In these cases, other methods are suggested as appropriate for trial as alternatives. In all cases, duplicates, spikes, and blanks were used to establish performance of the methods for the specific waste matrix. Results focused on problems in using the methods tested on the samples, the suitability of the ICP method of determining EP Toxicity metal ions and 22 EPA pollutant metal ions, and the suitability of cold vapor atomic absorption (CVAA) for mercury determinations. Problems areas identified are ICP spectral corrections, poor reproducibility from water leach and EP Toxicity methods, and adjustments needed for mercury analysis by CVAA. Section 3.0, Organics Analysis, details two screening procedures [total organic carbon (TOC) and gas chromatography (GC)], extraction procedures and related problems, surrogate spiking to test extraction efficiencies and matrix effects, and semivolatile organics via GC/mass spectroscopy (MS). The results show that the GC/MS is vulnerable to fouling and overload and that a combination of dilution and perhaps acidification are required to provide acceptable results. NPH and silicone-based lubricants from the sampling process impact the semivolatile analysis; however, with some modification the semivolatile method based on EPA SOW 288 can be used. Section 4.0, Radionuclide Analysis, evaluates procedures used to measure the radionuclides that might be found in the SST tank waste samples and establishes the level of accuracy and precision that can be expected. These data reveal that additional procedure development is needed in order to measure all of the radionuclides listed in Table 4-14 of the Waste Characterization Plan. In addition, the archive samples analyzed may not be representative of the tank population and considerable adaptation of the radiochemical procedures may be necessary to perform the desired measurements. NPH tests were conducted to determine whether the NPH from the field sampling process extracted significan

  5. Alcohol involvement and the Five-Factor model of personality: a meta-analysis.

    PubMed

    Malouff, John M; Thorsteinsson, Einar B; Rooke, Sally E; Schutte, Nicola S

    2007-01-01

    The purpose of this meta-analysis was to quantify the relationship between the Five-Factor Model of personality and alcohol involvement and to identify moderators of the relationship. The meta-analysis included 20 studies, 119 effect sizes, and 7,886 participants. Possible moderators examined included: five-factor rating type (self vs. other); study time-frame (cross sectional vs. longitudinal); sample type (treatment vs. non-treatment); type of alcohol involvement measure used; gender of the participants; and age of the participants. The meta-analysis showed alcohol involvement was associated with low conscientiousness, low agreeableness, and high neuroticism, a personality profile that: a) fits on the low end of a superordinate personality dimension that has been called self-control; and b) makes treatment difficult. Several significant moderators of effect size were found, including the following: studies of individuals in treatment for alcohol problems showed a more negative pattern of personality traits than did other studies; cross-sectional studies, but not longitudinal studies, showed a significant effect for agreeableness, perhaps suggesting that low agreeableness may have a different causal link to alcohol involvement from the other factors; mixed-sex samples tended to have lower effect sizes than single-sex samples, suggesting that mixing sexes in data analysis may obscure effects. PMID:18047183

  6. Sexual Problems in Men

    MedlinePLUS

    Many men have sexual problems. They become more common as men age. Problems can include Erectile dysfunction Reduced or lost interest in sex Problems with ejaculation Low testosterone Stress, illness, medicines, or emotional problems may also be factors. Occasional problems with sexual ...

  7. [Nail involvement in leprosy].

    PubMed

    Belinchón Romero, I; Ramos Rincón, J M; Reyes Rabell, F

    2012-05-01

    Leprosy, a disease caused by Mycobacterium leprae, primarily affects the skin and nerves, but the nails are also involved in as many as 3 out of 4 patients .The factors that trigger nail changes in leprosy are numerous and include repeated trauma, neuropathy, vascular impairment, infections, lepra reactions, and the drugs used to manage the disease. The changes most often reported include subungual hematomas, onycholysis, onychauxis, onychogryphosis, pterygium unguis, and onychoheterotopia, most of which can be attributed to nerve damage and trauma. Furthermore, the acro-osteolysis that occurs in the advanced stages of the disease may present with brachyonychia, racquet nails, or even anonychia. Infections of the nail bed leading to paronychia and onychomycosis should also be taken into account in leprosy. Other typical changes include longitudinal striae, pitting, macrolunula, Terry nails, leukonychia, hapalonychia, and Beau lines. In this review, we describe the principal nail changes associated with leprosy. These changes, which are highly varied and diverse in origin, are in fact a reflection of the significant morbidity caused by M. leprae infection. PMID:22056258

  8. Microstructural lines involving luminescence

    NASA Astrophysics Data System (ADS)

    Shimada, Kazuhiko

    2004-06-01

    Japanese National Printing Bureau has been focused upon the development of anti-copy lines for many years. The basic concept with regard to security measure lies in the merge of art and technology. On this basis, our originally developed anti-copy lines show flexibility to various security designs. Our newest anti-copy lines comprising from the Tri-Branched and Divided Lines shows clearer latent image effect compared to that of our other developed anti-copy lines. However, the anti-copy effect of security printing lines with microstructure is deteriorating due to the emergence of digital image techniques with higher resolution. In this situation, this paper introduces a new security measure comprising from luminescence and security printing lines with microstructure. It gives rise to a latent image effect under UV light due to the characteristic microstructure while visually same density. The principle advantage is that the combination of the anti-copy and luminescent feature strongly enhances its secure effect in documents. There is no necessity of two kinds of inks and any specially designed equipment to produce security documents with microstructural lines involving luminescence.

  9. Balance problems after unilateral lateral ankle sprains.

    PubMed

    Akbari, Mohammad; Karimi, Hossein; Farahini, Hossein; Faghihzadeh, Soghrat

    2006-01-01

    Abstract-Ankle ligament injury is the most common injury in athletic activities. This study examined balance problems in athletes with acute lateral ankle sprains. Thirty male athletes aged 20 to 35 years with right dominant side and traumatic ankle sprain were recruited through simple nonprobability sampling. We measured the sway index and limits of stability with the Biodex Balance System under different conditions. Functional balance was evaluated with two clinical tests: the Functional Reach Test and the Star-Excursion Balance Test. The results showed that balance ability in patients with acute lateral ankle sprain was significantly weaker under closed- versus open-eye conditions. Symmetry of weight-bearing on involved and sound limb in bilateral standing was not significantly different, but weight-bearing on the nondominant limb was significantly higher than on the dominant limb. We can conclude that balance problems occur after acute ankle sprains because of proprioception deficits and that the unconscious (reflexive) aspect of proprioception is more severely affected than the conscious (voluntary) aspect. PMID:17436168

  10. Optimization and geophysical inverse problems

    SciTech Connect

    Barhen, J.; Berryman, J.G.; Borcea, L.; Dennis, J.; de Groot-Hedlin, C.; Gilbert, F.; Gill, P.; Heinkenschloss, M.; Johnson, L.; McEvilly, T.; More, J.; Newman, G.; Oldenburg, D.; Parker, P.; Porto, B.; Sen, M.; Torczon, V.; Vasco, D.; Woodward, N.B.

    2000-10-01

    A fundamental part of geophysics is to make inferences about the interior of the earth on the basis of data collected at or near the surface of the earth. In almost all cases these measured data are only indirectly related to the properties of the earth that are of interest, so an inverse problem must be solved in order to obtain estimates of the physical properties within the earth. In February of 1999 the U.S. Department of Energy sponsored a workshop that was intended to examine the methods currently being used to solve geophysical inverse problems and to consider what new approaches should be explored in the future. The interdisciplinary area between inverse problems in geophysics and optimization methods in mathematics was specifically targeted as one where an interchange of ideas was likely to be fruitful. Thus about half of the participants were actively involved in solving geophysical inverse problems and about half were actively involved in research on general optimization methods. This report presents some of the topics that were explored at the workshop and the conclusions that were reached. In general, the objective of a geophysical inverse problem is to find an earth model, described by a set of physical parameters, that is consistent with the observational data. It is usually assumed that the forward problem, that of calculating simulated data for an earth model, is well enough understood so that reasonably accurate synthetic data can be generated for an arbitrary model. The inverse problem is then posed as an optimization problem, where the function to be optimized is variously called the objective function, misfit function, or fitness function. The objective function is typically some measure of the difference between observational data and synthetic data calculated for a trial model. However, because of incomplete and inaccurate data, the objective function often incorporates some additional form of regularization, such as a measure of smoothness or distance from a prior model. Various other constraints may also be imposed upon the process. Inverse problems are not restricted to geophysics, but can be found in a wide variety of disciplines where inferences must be made on the basis of indirect measurements. For instance, most imaging problems, whether in the field of medicine or non-destructive evaluation, require the solution of an inverse problem. In this report, however, the examples used for illustration are taken exclusively from the field of geophysics. The generalization of these examples to other disciplines should be straightforward, as all are based on standard second-order partial differential equations of physics. In fact, sometimes the non-geophysical inverse problems are significantly easier to treat (as in medical imaging) because the limitations on data collection, and in particular on multiple views, are not so severe as they generally are in geophysics. This report begins with an introduction to geophysical inverse problems by briefly describing four canonical problems that are typical of those commonly encountered in geophysics. Next the connection with optimization methods is made by presenting a general formulation of geophysical inverse problems. This leads into the main subject of this report, a discussion of methods for solving such problems with an emphasis upon newer approaches that have not yet become prominent in geophysics. A separate section is devoted to a subject that is not encountered in all optimization problems but is particularly important in geophysics, the need for a careful appraisal of the results in terms of their resolution and uncertainty. The impact on geophysical inverse problems of continuously improving computational resources is then discussed. The main results are then brought together in a final summary and conclusions section.

  11. 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.

  12. 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…

  13. 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

  14. Problem Solved: How To Coach Cognition.

    ERIC Educational Resources Information Center

    Krynock, Karoline; Robb, Louise

    1999-01-01

    When faced with real-world problems, students devise accurate, logical, and creative solutions using skills connecting to different subject areas. Students are intrigued by assignments involving preservation of species and design of environmentally friendly products and transit systems. Problem-based learning depends on coaching, modeling, and

  15. Local History and Problem-Based Learning

    ERIC Educational Resources Information Center

    Wieseman, Katherine C.; Cadwell, Doni

    2005-01-01

    The combination of students, local history, researching, and problem-based learning creates a powerful opportunity for learning to all involved. This article provides one example of how an elementary teacher and a teacher educator have used local resources and problem-based learning to teach a fourth grade unit about human communities and the…

  16. Taking "From Scratch" out of Problem Solving

    ERIC Educational Resources Information Center

    Brown, Wayne

    2007-01-01

    Solving problems and creating processes and procedures from the ground up has long been part of the IT department's way of operating. IT staffs will continue to encounter new problems to solve and new technologies to be implemented. They also must involve their constituents in the creation of solutions. Nonetheless, for many issues they no longer…

  17. Helping Ourselves: Local Solutions to Global Problems.

    ERIC Educational Resources Information Center

    Stokes, Bruce

    Solutions to global problems such as inflation, tightening energy supplies, and deteriorating environmental quality lie at the local level where the consequences are most obvious, the motivation to get involved is most direct, and the benefits of action are most immediate. Examples of problems regarding energy, the workplace, food production,

  18. A Boundary Value Problem for Introductory Physics?

    ERIC Educational Resources Information Center

    Grundberg, Johan

    2008-01-01

    The Laplace equation has applications in several fields of physics, and problems involving this equation serve as paradigms for boundary value problems. In the case of the Laplace equation in a disc there is a well-known explicit formula for the solution: Poisson's integral. We show how one can derive this formula, and in addition two equivalent…

  19. How to Generate Good Profit Maximization Problems

    ERIC Educational Resources Information Center

    Davis, Lewis

    2014-01-01

    In this article, the author considers the merits of two classes of profit maximization problems: those involving perfectly competitive firms with quadratic and cubic cost functions. While relatively easy to develop and solve, problems based on quadratic cost functions are too simple to address a number of important issues, such as the use of

  20. Taking "From Scratch" out of Problem Solving

    ERIC Educational Resources Information Center

    Brown, Wayne

    2007-01-01

    Solving problems and creating processes and procedures from the ground up has long been part of the IT department's way of operating. IT staffs will continue to encounter new problems to solve and new technologies to be implemented. They also must involve their constituents in the creation of solutions. Nonetheless, for many issues they no longer