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1

Sampling problems  

NASA Technical Reports Server (NTRS)

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).

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

2

Adaptive sampling for noisy problems  

SciTech Connect

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.

Cantu-Paz, E

2004-03-26

3

Physics Suite Sample Problems: Magnetism  

NSDL National Science Digital Library

This page contains a series of problems on the topic of magnetism developed for use with The Physics Suite, an activity-based learning project. Each problem was designed to help build qualitative understanding of physics and was built around student acquisition of knowledge as observed in recent studies. The problems vary in format and include estimation, context-based reasoning, multiple choice, short answer, qualitative questions, and essay questions. The topics include magnetic forces and fields, magnetic induction, mass spectrometers, Ampere's Law, inducing current, and Faraday's Law. This item is part of a larger collection of problems, in-class questions, and interactive resources developed by the University of Maryland Physics Education Research Group.

Redish, Edward F.

2008-07-22

4

Several-sample location problem  

Microsoft Academic Search

\\u000a In this chapter we consider tests and estimates based on identity, spatial sign, and spatial rank scores in the several independent\\u000a samples setting. We get multivariate extensions of the Moods test, Wilcoxon-Mann-Whitney test, Kruskal- Wallis test and the\\u000a two samples Hodges-Lehmann estimator. Equivariant\\/invariant versions are found using inner centering and standardization.

Hannu Oja

5

DECOMPOSITION AND SAMPLING METHODS STOCHASTIC EQUILIBRIUM PROBLEMS  

E-print Network

DECOMPOSITION AND SAMPLING METHODS FOR STOCHASTIC EQUILIBRIUM PROBLEMS a dissertation submitted of the resulting algorithm is proved. We also present a cut-sampling method that uses a sample of the cuts by as much as 40%. The sampling method results in solutions that are within 3% of the optimal solution when

Stanford University

6

Answer Key: Sample Test 1. Problem 10  

E-print Network

? Yes No Total Test is positive 3.92% 2.88% 6.8% Test is negative 0.08% 93.12% 93.2% Total 4% 96% 100Answer Key: · Sample Test 1. Problem 10 Mean: 2.05 phones Standard Deviation: 1.0234 phones · Sample Test 2. Problem 1a Mean: 2.264 points of GPA Standard Deviation: 1.0101 points of GPA · Sample

Abrego, Bernardo

7

Processes Involved in Mathematical Divergent Problem Solving.  

ERIC Educational Resources Information Center

The focus of this study was on the processes students used in making mathematical conjectures for five divergent problem situations. The relationship of the processes to creativity factors across the problems was also examined. The results of various cluster analyses and correlational measures indicated that students use different sequences of

Brandau, Linda I.; Dossey, John A.

8

A unified conic formulation for convex problems involving powers  

E-print Network

A unified conic formulation for convex problems involving powers Fran¸cois Glineur francois / MOPTA 07 A unified conic formulation for convex problems involving powers 1 #12;Overview 1. Motivation ICCOPT II / MOPTA 07 A unified conic formulation for convex problems involving powers 2 #12;Overview 1

Glineur, François

9

Solving convex problems involving powers using conic optimization  

E-print Network

Solving convex problems involving powers using conic optimization and a new self-concordant barrier CFG 07 Heidelberg University CFG 07 Solving convex problems involving powers using conic optimization 1 #12;Overview 1. Motivation Why convex optimization? Why a conic formulation? 2. Unified conic

Glineur, François

10

Stochastic Nash Equilibrium Problems: Sample Average ...  

E-print Network

the problem and the first order equilibrium conditions are characterized in terms of .... of convergence is usually obtained by applying classical uniform strong law of ...... V. Piccialli, Generalized Nash equilibrium problems and Newton methods,.

2010-01-22

11

Problem-Based Learning Laboratories Involving Chemicals From Biorenewables  

Microsoft Academic Search

At Iowa State University, we have developed a unique and valuable experience for our students by giving them an opportunity to work in multidisciplinary teams on cutting-edge problems involving biorenewables, while using novel problem-based learning approaches. The focus of four new 1-credit laboratory classes is to bring important emergent areas from the development of biorenewable sources of chemicals into new

Charles Glatz; Balaji Narasimhan; Jacqueline Shanks; Mary Huba; Kevin Saunders; Peter Reilly; Surya Mallapragada

2004-01-01

12

Selective sampling methods in one-class classification problems  

E-print Network

Selective sampling methods in one-class classification problems Piotr Juszczak, Robert P.W. Duin often used selective sampling methods for two- or multi-class problems are not necessarily the best ones for the one-class classification problem. By modifying the sampling methods, we present a way of selecting

Duin, Robert P.W.

13

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

ERIC Educational Resources Information Center

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

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

2013-01-01

14

Power and Sample Size Calculations for Studies Involving Linear Regression  

Microsoft Academic Search

This article presents methods for sample size and power calculations for studies involving linear regression. These approaches are applicable to clinical trials designed to detect a regression slope of a given magnitude or to studies that test whether the slopes or intercepts of two independent regression lines differ by a given amount. The investigator may either specify the values of

William D. Dupont; Walton D. Plummer

1998-01-01

15

Physics Suite Sample Problems: Momentum and Energy  

NSDL National Science Digital Library

This page contains a series of problems on the topic of momentum developed for use with The Physics Suite, an activity-based learning project. Each problem was designed to help build qualitative understanding of physics and was built around student acquisition of knowledge as observed in recent studies. The problems vary in format and include estimation, context-based reasoning, multiple choice, short answer, qualitative questions, and essay questions. Topics covered include conservation of energy, conservation of momentum, collisions, springs, gravitational potential energy, work, and graphical analysis. This item is part of a larger collection of problems, in-class questions, and interactive resources developed by the University of Maryland Physics Education Research Group.

Redish, Edward F.

2008-07-19

16

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

PubMed

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

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

2014-06-01

17

CAUSES OF PROBLEMS IN ANALYZING PE SAMPLES  

EPA Science Inventory

The U.S. EPA's Environmental Monitoring Systems Laboratory in Las Vegas (EMSL-LV), is responsible for overseeing quality assurance of EPA's Superfund Contract Laboratory Program. n part, this oversight role involves examining QA data provided by the labs in order to investigate p...

18

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

PubMed Central

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

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

2010-01-01

19

Sample Size Problems In Anova: Bayesian Point Of View  

E-print Network

this paper we discuss the sample size problem for balanced one way ANOVA under a posterior Bayesian formulation of the problem. Using the distribution theory of appropriate quadratic forms we derive explicit sample sizes for prespecified posterior precisions. Comparisons with classical sample sizes are made. Instead of extensive tables, a mathematica program for sample size calculation is given. The formulations given in this article form a foundational step towards Bayesian calculation of sample size, in general.

Anirban Dasgupta; Brani Vidakovic

20

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

ERIC Educational Resources Information Center

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

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

2008-01-01

21

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

ERIC Educational Resources Information Center

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

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

2011-01-01

22

Solving the Small Sample Size Problem of LDA  

Microsoft Academic Search

The small sample size problem is often encountered in pattern recognition. It results in the singularity of the within-class scatter matrix Sw in Linear Discriminant Analysis (LDA). Different methods have been proposed to solve this problem in face recognition literature. Some methods reduce the dimension of the original sample space and hence unavoidably remove the null space of Sw, which

Rui Huang; Qingshan Liu; Hanqing Lu; Songde Ma

2002-01-01

23

A Nonparametric Test for the Problem of Several Samples  

Microsoft Academic Search

In this paper, a new nonparametric test for the problem of $c$ samples is offered. It is based upon the numbers of $c$-plets that can be formed by choosing one observation from each sample such that the observation from the $i$th sample is the least, $i = 1, 2, \\\\cdots, c$. The asymptotic distribution of the new test statistic is

V. P. Bhapkar

1961-01-01

24

The discrete Kramer sampling theorem and indeterminate moment problems  

Microsoft Academic Search

Abstract In this paper we propose candidates to be the kernel appearing in the discrete Kramer sampling theorem. These kernels arise either from orthonormal polynomials associated with indeterminate Hamburger or Stieltjes moment problems, or from the second kind orthogonal polynomials associated with the former ones. The sampling points are given by the zeros of the denominator in the Nevanlinna parametrization

A. G. Garc A; M. A. Hernandez-medina

2001-01-01

25

The discrete Kramer sampling theorem and indeterminate moment problems  

Microsoft Academic Search

In this paper we propose candidates to be the kernel appearing in the discrete Kramer sampling theorem. These kernels arise either from orthonormal polynomials associated with indeterminate Hamburger or Stieltjes moment problems, or from the second kind orthogonal polynomials associated with the former ones. The sampling points are given by the zeros of the denominator in the Nevanlinna parametrization of

Antonio G. Garc??a; Miguel A. Hernndez-Medina

2001-01-01

26

The discrete Kramer sampling theorem and indeterminate moment problems  

Microsoft Academic Search

In this paper we propose candidates to be the kernel appearing in the discrete Kramer sampling theorem. These kernels arise either from orthonormal polynomials associated with indeterminate Hamburger or Stieltjes moment problems, or from the second kind orthogonal polynomials associated with the former ones. The sampling points are given by the zeros of the denominator in the Nevanlinna parametrization of

Antonio G. Gar

27

Multiscale treatment of mechanical contact problems involving thin polymeric layers  

NASA Astrophysics Data System (ADS)

We propose a strategy to obtain a hyperelastic constitutive law for film-like systems from molecular dynamics (MD) simulations. The aim is to furnish a computationally efficient continuum model with this description of the material. In particular, two different methods are suggested, both of which consist of virtual experiments that are performed on the material to sample systematically the stress-strain relation. The latter is then fitted to a suitable functional form. We use a polymeric self-assembled monolayer, which spans a height of only a few nanometers, as a test case. Having determined the response function, we then apply it within a finite-element simulation of a continuum mechanical nanoindentation problem. Several contact quantities such as normal reaction forces and the contact geometry are extracted from these calculations and are compared to those from an analogous, fully atomistic nanoindentation simulation. We find that the considered benchmark quantities as obtained from the continuum surrogate model reproduce well the corresponding values of the MD simulation.

Schmidt, Marcus G.; Sauer, Roger A.; Ismail, Ahmed E.

2014-06-01

28

Crack problems involving nonhomogeneous interfacial regions in bonded materials  

NASA Technical Reports Server (NTRS)

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

Erdogan, F.

1990-01-01

29

Quantum Measurements for Hidden Subgroup Problems with Optimal Sample Complexity  

E-print Network

One of the central issues in the hidden subgroup problem is to bound the sample complexity, i.e., the number of identical samples of coset states sufficient and necessary to solve the problem. In this paper, we present general bounds for the sample complexity of the identification and decision versions of the hidden subgroup problem. As a consequence of the bounds, we show that the sample complexity for both of the decision and identification versions is $\\Theta(\\log|\\HH|/\\log p)$ for a candidate set $\\HH$ of hidden subgroups in the case that the candidate subgroups have the same prime order $p$, which implies that the decision version is at least as hard as the identification version in this case. In particular, it does so for the important instances such as the dihedral and the symmetric hidden subgroup problems. Moreover, the upper bound of the identification is attained by the pretty good measurement. This shows that the pretty good measurement can identify any hidden subgroup of an arbitrary group with at most $O(\\log|\\HH|)$ samples.

Masahito Hayashi; Akinori Kawachi; Hirotada Kobayashi

2006-04-24

30

Problem and pathological gambling in a sample of casino patrons.  

PubMed

Relatively few studies have examined gambling problems among individuals in a casino setting. The current study sought to examine the prevalence of gambling problems among a sample of casino patrons and examine alcohol and tobacco use, health status, and quality of life by gambling problem status. To these ends, 176 casino patrons were recruited by going to a Southern California casino and requesting that they complete an anonymous survey. Results indicated the following lifetime rates for at-risk, problem, and pathological gambling: 29.2, 10.7, and 29.8%. Differences were found with regards to gambling behavior, and results indicated higher rates of smoking among individuals with gambling problems, but not higher rates of alcohol use. Self-rated quality of life was lower among pathological gamblers relative to non-problem gamblers, but did not differ from at-risk or problem gamblers. Although subject to some limitations, our data support the notion of higher frequency of gambling problems among casino patrons and may suggest the need for increased interventions for gambling problems on-site at casinos. PMID:20549549

Fong, Timothy W; Campos, Michael D; Brecht, Mary-Lynn; Davis, Alice; Marco, Adrienne; Pecanha, Viviane; Rosenthal, Richard J

2011-03-01

31

The discrete Kramer sampling theorem and indeterminate moment problems  

NASA Astrophysics Data System (ADS)

In this paper we propose candidates to be the kernel appearing in the discrete Kramer sampling theorem. These kernels arise either from orthonormal polynomials associated with indeterminate Hamburger or Stieltjes moment problems, or from the second kind orthogonal polynomials associated with the former ones. The sampling points are given by the zeros of the denominator in the Nevanlinna parametrization of the N-extremal measures. Explicit formulae are given associated with some cases where the Nevanlinna parametrization is known explicitly.

Garca, Antonio G.; Hernndez-Medina, Miguel A.

2001-09-01

32

Defining the Mars Ascent Problem for Sample Return  

Microsoft Academic Search

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

2008-01-01

33

Feature Extractions for Small Sample Size Classification Problem  

Microsoft Academic Search

Much research has shown that the definitions of within-class and between-class scatter matrices and regularization technique are the key components to design a feature extraction for small sample size problems. In this paper, we illustrate the importance of another key component, eigenvalue decomposition method, and a new regularization technique was proposed. In the hyperspectral image experiment, the effects of these

Bor-Chen Kuo; Kuang-Yu Chang

2007-01-01

34

A Guide to Recycled Papers: Problems, Sources, and Samples.  

ERIC Educational Resources Information Center

This guide explains what is involved in recycling paper. Some background history is presented on the use of recycled paper. Sources of use for this product are pointed out, especially instances where business and industry have found that recycled paper could be used in place of the virgin product. The major part of the guide consists of samples of

Carroll, Katherine

35

Sampling Methods For Bayesian Nonparametric Inference Involving Stochastic Processes  

Microsoft Academic Search

\\u000a An algorithm for simulating the class of neutral to the right processes is described. The mixture of Dirichlet processes (MDP)\\u000a model has proved to be successful in a variety of contexts. A new sampling method, using auxiliary variables, for MDP models\\u000a is developed and exemplified.

Stephen Walker; Paul Damien

36

Some New Twists to Problems Involving the Gaussian Probability Integral  

NASA Technical Reports Server (NTRS)

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).

Simon, Marvin K.; Divsalar, Dariush

1997-01-01

37

Enhanced multilevel linear sampling methods for inverse scattering problems  

NASA Astrophysics Data System (ADS)

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.

Li, Jingzhi; Liu, Hongyu; Wang, Qi

2014-01-01

38

Sampling problems: The small scale structure of precipitation  

NASA Technical Reports Server (NTRS)

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.

Crane, R. K.

1981-01-01

39

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

PubMed Central

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

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

1980-01-01

40

Defining the Mars Ascent Problem for Sample Return  

SciTech Connect

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.

Whitehead, J

2008-07-31

41

Regularized discriminant analysis for the small sample size problem in face recognition  

E-print Network

Regularized discriminant analysis for the small sample size problem in face recognition Juwei Lu sample size'' (SSS) problem arising from the small number of available training samples compared. Keywords: Linear discriminant analysis; Quadratic discriminant analysis; Small sample size; Regularization

Plataniotis, Konstantinos N.

42

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

ERIC Educational Resources Information Center

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

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

2013-01-01

43

Child involvement in interparental conflict and child adjustment problems: a longitudinal study of violent families.  

PubMed

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 10years 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 6months 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

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

2014-07-01

44

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

NASA Technical Reports Server (NTRS)

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

Rosen, I. G.; Wang, C.

1992-01-01

45

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

NASA Technical Reports Server (NTRS)

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.

Rosen, I. G.; Wang, C.

1990-01-01

46

The Sample Average Approximation Method Applied to Stochastic Routing Problems: A Computational Study  

Microsoft Academic Search

The sample average approximation (SAA) method is an approach for solving stochastic optimization problems by using Monte Carlo simulation. In this technique the expected objective function of the stochastic problem is approximated by a sample average estimate derived from a random sample. The resulting sample average approximating problem is then solved by deterministic optimization techniques. The process is repeated with

Bram Verweij; Shabbir Ahmed; Anton J. Kleywegt; George Nemhauser; Alexander Shapiro

2003-01-01

47

How to ask an expert for new samples in the one-class classification problem?  

E-print Network

-class classification problem, selective sampling methods, active learning Abstract Selective sampling, a part is to show why the best or most often used selective sampling methods for two- or multi- class problems are not necessarily the best ones for the one-class classification problem. By modifying the sampling methods, we

Duin, Robert P.W.

48

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

NASA Technical Reports Server (NTRS)

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.

Rosen, I. G.; Wang, C.

1989-01-01

49

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

ERIC Educational Resources Information Center

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

Locke, Benjamin D.; Mahalik, James R.

2005-01-01

50

Relationship of the Family Environment to Children's Involvement in Bully\\/Victim Problems at School  

Microsoft Academic Search

Previous studies regarding the relationship of the family environment to children's involvement in bully\\/victim problems at school primarily focused on children's perceptions of family dimensions. No studies were known using data from multiple reporters within 1 family (parents and children) on family characteristics of bully\\/victim problems. The aim of this study was to investigate differences between families of victims, bullies,

V. Stevens; I. De Bourdeaudhuij; P. Van Oost

2002-01-01

51

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

E-print Network

Parabolic equation solution of seismo-acoustics problems involving variations in bathymetry to extend this approach to a larger class of seismo-acoustics problems. The variable rotated parabolic equation J. Acoust. Soc. Am. 120, 3534­3538 2006 handles a sloping fluid-solid interface at the ocean

52

The Effect of Teacher's Invitations to Parental Involvement on Children's Externalizing Problem Behaviors: An  

E-print Network

-Dempsey, Walker, Sandler, Whetsel, Green, Wilkins, & Closson, 2005). One important influence on parents feeling involvement can take many forms including encouraging frequent teacher-parent communication about the child1 The Effect of Teacher's Invitations to Parental Involvement on Children's Externalizing Problem

Farritor, Shane

53

Physics Suite Sample Problems: Circular and Rotational Motion  

NSDL National Science Digital Library

This page contains a series of problems on the topic of circular and rotational motion developed for use with The Physics Suite, an activity-based learning project. Each problem was designed to help build qualitative understanding of physics and was built around student acquisition of knowledge as observed in recent studies. The problems vary in format and include estimation, context-based reasoning, multiple choice, short answer, qualitative questions, and essay questions. Topics covered include rotational energy, torque, angular momentum, and rotational kinematics. This item is part of a larger collection of problems, in-class questions, and interactive resources developed by the University of Maryland Physics Education Research Group.

Redish, Edward F.

2008-07-18

54

Behaviour Problems across Home and Kindergarten in an Australian Sample  

ERIC Educational Resources Information Center

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

Herrera, Maite; Little, Emma

2005-01-01

55

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

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

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

2013-01-01

56

An empirical coverage test for the g-sample problem  

USGS Publications Warehouse

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.

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

1991-01-01

57

The effect of unlabeled samples in reducing the small sample size problem and mitigating the Hughes phenomenon  

Microsoft Academic Search

The authors study the use of unlabeled samples in reducing the problem of small training sample size that can severely affect the recognition rate of classifiers when the dimensionality of the multispectral data is high. The authors show that by using additional unlabeled samples that are available at no extra cost, the performance may be improved, and therefore the Hughes

Behzad M. Shahshahani; David A. Landgrebe

1994-01-01

58

Sampling-based algorithms for optimal path planning problems  

E-print Network

Sampling-based motion planning received increasing attention during the last decade. In particular, some of the leading paradigms, such the Probabilistic RoadMap (PRM) and the Rapidly-exploring Random Tree (RRT) algorithms, ...

Karaman, Sertac

2012-01-01

59

Communication Problems in Turner Syndrome: A Sample Survey.  

ERIC Educational Resources Information Center

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.

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

1999-01-01

60

SAMPLE SURVEY STATISTICS TEACHING: AN ALMOST WORLDWIDE PROBLEM ON TEACHING AGRICULTURAL SURVEY METHODS  

E-print Network

Most national or large-scale multiple-purpose Agricultural Surveys, because of their complex nature, should be based on multiple frame survey designs that use samples selected from an area frame, list frames of holdings and housing units, and point sampling methods. The problem is that, although such Agricultural Surveys imply important human and economic resources as well as time for their implementation and maintenance, the area and multiple frame survey methods already mentioned are simply not taught at most universities and statistical teaching institutions. In other words, it has been almost a worldwide tradition to teach in an inappropriate way agricultural survey methods. However those methods are widely used and involve specialized statistical knowledge for their implementation and analysis. In this paper we shall refer to the reasons of such lack of appropriate teaching as well as possible solutions.

lvaro Gonzlez Villalobos

61

AN INVESTIGATION OF A PRESERVICE TEACHER'S USE OF REPRESENTATIONS IN SOLVING ALGEBRAIC PROBLEMS INVOLVING EXPONENTIAL RELATIONSHIPS  

Microsoft Academic Search

As part of a larger investigation of preservice teachers' use of, and movement amongst, various modes of representing exponential relationships, this report focuses on one case study, that of Mike, whose facility in moving amongst representational registers was not matched by conceptual understanding of the underlying mathematical ideas as he attempted to solve algebraic problems involving exponential relationships. Mike's case

Norma Presmeg; Rajeev Nenduradu

62

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

ERIC Educational Resources Information Center

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

Ybrandt, Helene

2010-01-01

63

Introduction This work is concerned with the exterior structural acoustics problem involving the  

E-print Network

Chapter 1 Introduction This work is concerned with the exterior structural acoustics problem involving the interaction of vibrating structures submerged in an infinite acoustic fluid and requires solution of the coupled wave equation subject to a far­field radiation condition. The acoustic fluid

Thompson, Lonny L.

64

Problems in sampling the Native American and Alaska Native populations  

Microsoft Academic Search

Selecting a scientific national sample of Native Americans and Alaska Natives is difficult for at least four reasons: (1) they are a small proportion of the total population, (2) they are not so segregated that geographic oversampling can reach most of the population, (3) criteria for deciding who is a member of the Native American and Alaska Native population are

EUGENE P. ERICKSEN

1997-01-01

65

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

NASA Astrophysics Data System (ADS)

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.

Tabor-Morris, A. E.

2013-03-01

66

CSC 2400 Exercises on Pointers in C This handout involves playing with a number of C programs to solve some problems involving pointers.  

E-print Network

to solve some problems involving pointers. There are 4 different problems. Work on as many as you can, because it points to memory space not allocated to your program */ return 0; } #12;Exercise 4 /* p4.c swapCSC 2400 ­ Exercises on Pointers in C This handout involves playing with a number of C programs

67

Solving practical problems in environmental sampling for chemical agents and their degradation compounds  

SciTech Connect

The analyses of environmental samples for chemical agent degradation products were conducted using analytical test methods designed for evaluation of solid waste samples. All methods are found in the 3rd Edition of EPA`s compendium of analytical methods (SW-846) dated July 1992. These EPA methods are recommended for compliance testing required by the Resource Conservation and Recovery Act (RCRA) and are routinely used for the analysis of environmental samples. In the past several years, these same methods were used to support the survey of areas suspected of having chemical agent or chemical agent degradation compound contamination. An overview is presented of the U.S. Army Center for Health Promotion and Preventive Medicine`s (previously the U.S. Army Environmental Hygiene Agency) involvement with the analysis of samples for chemical agents and their degradation compounds collected from sites such as Tooele Army Depot, Rocky Mt. Arsenal, Newport Army Depot, Johnston Island, and Spring Valley, (a residential site near American University in Washington D.C.) Discussed are practical problems encountered during a quick response of a non-surety laboratory to analyze environmental samples for agents and their degradation compounds.

Williams, K.E.; Sheely, M.V. [Army Center for Health Promotion and Preventive Medicine, Aberdeen Proving Ground, MD (United States)

1995-06-01

68

Relational Discriminant Analysis and Its Large Sample Size Problem Robert P.W. Duin  

E-print Network

Relational Discriminant Analysis and Its Large Sample Size Problem Robert P.W. Duin Pattern. This technique has a large sample size problem as the size of the similarity matrix equals the square suffers from a feature size - sample size dilemma. Better, more complete object representations, yield

Duin, Robert P.W.

69

SAMPLE SIZE PROBLEMS IN ANOVA: BAYESIAN POINT OF Anirban DasGupta  

E-print Network

SAMPLE SIZE PROBLEMS IN ANOVA: BAYESIAN POINT OF VIEW 1 By Anirban DasGupta Purdue University and Brani Vidakovic Duke University In this paper we discuss the sample size problem for balanced one way of appropriate quadratic forms we derive explicit sample sizes for prespecified posterior precisions. Comparisons

West, Mike

70

SAMPLE SIZE PROBLEMS IN ANOVA: BAYESIAN POINT OF Anirban DasGupta  

E-print Network

SAMPLE SIZE PROBLEMS IN ANOVA: BAYESIAN POINT OF VIEW1 By Anirban DasGupta Purdue University and Brani Vidakovic Duke University In this paper we discuss the sample size problem for balanced one way of appropriate quadratic forms we derive explicit sample sizes for prespeci ed posterior precisions. Comparisons

West, Mike

71

Psychiatric morbidity and people's experience of and response to social problems involving rights.  

PubMed

Psychiatric morbidity has been shown to be associated with the increased reporting of a range of social problems involving legal rights ('rights problems'). Using a validated measure of psychiatric morbidity, this paper explores the relationship between psychiatric morbidity and rights problems and discusses the implications for the delivery of health and legal services. New representative national survey data from the English and Welsh Civil and Social Justice Survey (CSJS) surveyed 3040 adults in 2007 to explore the relationship between GHQ-12 scores and the self reported incidence of and behaviour surrounding, rights problems. It was found that the prevalence of rights problems increased with psychiatric morbidity, as did the experience of multiple problems. It was also found the likelihood of inaction in the face of problems increased with psychiatric morbidity, while the likelihood of choosing to resolve problems without help decreased. Where advice was obtained, psychiatric morbidity was associated with a greater tendency to obtain a combination of 'legal' and 'general' support, rather than 'legal' advice alone. The results suggest that integrated and 'outreach' services are of particular importance to the effective support of those facing mental illness. PMID:20522118

Balmer, Nigel J; Pleasence, Pascoe; Buck, Alexy

2010-11-01

72

MULTI-VALUED BOUNDARY VALUE PROBLEMS INVOLVING LERAY-LIONS OPERATORS,... 1 RENDICONTI DEL CIRCOLO MATEMATICO DI PALERMO  

E-print Network

MULTI-VALUED BOUNDARY VALUE PROBLEMS INVOLVING LERAY-LIONS OPERATORS,... 1 RENDICONTI DEL CIRCOLO MATEMATICO DI PALERMO Serie II, Tomo L (2001), pp. ??? MULTI-VALUED BOUNDARY VALUE PROBLEMS INVOLVING LERAY-LIONS a Leray-Lions operator. The proof combines monotonicity methods for elliptic problems, variational

Radulescu, Vicentiu

73

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

NASA Technical Reports Server (NTRS)

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.

Tamma, Kumar K.; Railkar, Sudhir B.

1988-01-01

74

Solving inverse problems involving the NavierStokes equations discretized by a LagrangeGalerkin method  

Microsoft Academic Search

In this article, we are investigating the numerical approximation of an inverse problem involving the evolution of a Newtonian viscous incompressible fluid described by the NavierStokes equations in 2D. This system is discretized using a low order finite element in space coupled with a LagrangeGalerkin scheme for the nonlinear advection operator. We introduce a full discrete linearized scheme that is

Gilles Fourestey; Marwan Moubachir

2005-01-01

75

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

Microsoft Academic Search

Among marginalized populations, homeless adults are known to have elevated rates of mental health and substance use problems\\u000a compared to the general population, but less is known about their youthful homeless counterparts. While few studies currently\\u000a exist, what research has been conducted among street-involved youth has confirmed high rates of comorbidity among this population.\\u000a However, few of these studies explore

Maritt Kirst; Tyler Frederick; Patricia G. Erickson

76

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

NASA Astrophysics Data System (ADS)

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

Ito, Yoshimichi; Shirahama, Hiroshi; Hagiwara, Tomomichi

77

Approximating connected facility location problems via random facility sampling and core detouring  

Microsoft Academic Search

We present a simple randomized algorithmic framework for connected facility location problems. The basic idea is as follows: We run a black-box approximation algorithm for the unconnected facility location problem, randomly sample the clients, and open the facilities serving sampled client s in the approximate solution. Via a novel analytical tool, which we term core detouring, we show that this

Friedrich Eisenbrand; Fabrizio Grandoni; Thomas Rothvo; Guido Schfer

2008-01-01

78

Approximating Connected Facility Location Problems via Random Facility Sampling and Core Detouring  

E-print Network

Approximating Connected Facility Location Problems via Random Facility Sampling and Core Detouring present a simple randomized algorithmic framework for connected facility location problems. The basic idea. For example, we reduce the approximation ratio for the connected facility location problem from 8.55 to 4

Nabben, Reinhard

79

Approximating Connected Facility Location Problems via Random Facility Sampling and Core Detouring  

E-print Network

Approximating Connected Facility Location Problems via Random Facility Sampling and Core Detouring a simple randomized algorithmic framework for connected facility location problems. The basic idea. For example, we reduce the approximation ratio for the connected facility location problem from 8.55 to 4

Nabben, Reinhard

80

Outcome of treatment for alcohol abuse and involvement in alcoholics anonymous among previously untreated problem drinkers  

Microsoft Academic Search

A sample of 515 initially untreated problem drinkers was followed for one year after contacting alcohol information and referral\\u000a or detoxification services. At a one-year follow-up, participants had self-selected into one of four groups: no treatment\\u000a (24%), Alcoholics Anonymous (AA) only (18%), outpatient treatment (25%), and residential or inpatient treatment (32%); some\\u000a outpatients also attended AA, and some inpatients also

Christine Timko; Rudolf H. Moos; John W. Finney; Bernice S. Moos

1994-01-01

81

The prevalence and incremental validity of identity problem symptoms in a high school sample.  

PubMed

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 problem. Identity problem symptoms predicted psychological symptom scores beyond identity status, and identity status accounted for substantially less variance in psychological symptom severity when controlling for identity problem symptoms. Additional research on the relationship between identity problems and psychological adjustment is needed and greater attention to the role of identity issues in clinical practice is warranted. PMID:18784912

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

2009-06-01

82

Finite difference time domain algorithm for electromagnetic problems involving material movement  

NASA Astrophysics Data System (ADS)

The finite difference time domain (FDTD) method, adapted for magnetic field diffusion problems, is used to study the electromagnetic induction in moving materials by including motional emf in standard FDTD electromagnetic equations. The material movement is implemented by continuously changing material properties in each computational cell consistent to material advection. The flux corrected transport (FCT) algorithm is used to transport magnetic field in a fixed eulerian cell. A higher time-step is achieved by artificially increasing permittivity of the medium. This new approach is validated with standard analytical solutions for planar magnetic flux compression system and magnetic field diffusion in moving conductors with a non-relativistic velocity. To our knowledge, this is the first approach to use FDTD method for electromagnetic problems involving material motion.

Sijoy, C. D.; Chaturvedi, Shashank

2009-04-01

83

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

NASA Technical Reports Server (NTRS)

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.

Markopoulos, N.; Calise, A. J.

1993-01-01

84

Math 243: Notes on Induction The homework problems on induction involve not just getting the equations to work out  

E-print Network

Math 243: Notes on Induction The homework problems on induction involve not just getting. This handout describes what's involved in doing this, and gives some additional details about how induction problems were graded on the HW and how they'll be graded on exams. · The base case of an induction argument

Jones, Rafe

85

Direct sampling of multiple single-molecular rupture dominant pathways involving a multistep transition.  

PubMed

We report a novel single-molecular rupture mechanism revealed by direct sampling of the dominant pathway using a self-optimized path sampling method. Multiple dominant pathways involving multistep transitions are identified. The rupture may take place via a direct unfolding from the native state to the unfolding state, or through a two-step pathway bypassing a distinct intermediate metastable state (IMS). This scenario facilitates us to propose a three-state kinetic model, which can produce a nonlinear dependence of the rupture time on pulling forces similar to the ones reported in the literature. In particular, molecule conformations in the IMS maintain an elongation of the tail at one terminal, by which external pulling will enhance the relative stability of IMS. Consequently, even though the overall transition rate of the multistep pathway is relatively small, the molecule still has to be ruptured via the multistep pathway rather than the direct pathway. Thus, our work demonstrates an IMS trapping effect induced rupture mechanism involving an abnormal switching from a fast dominant pathway to a slow one. PMID:25347216

Jiang, Huijun; Ding, Huai; Hou, Zhonghuai

2014-12-14

86

A numerical treatment of geodynamic viscous flow problems involving the advection of material interfaces  

NASA Technical Reports Server (NTRS)

Effective numerical treatment of multicomponent viscous flow problems involving the advection of sharp interfaces between materials of differing physical properties requires correction techniques to prevent spurious diffusion and dispersion. We develop a particular algorithm, based on modern shock-capture techniques, employing a two-step nonlinear method. The first step involves the global application of a high-order upwind scheme to a hyperbolic advection equation used to model the distribution of distinct material components in a flow field. The second step is corrective and involves the application of a global filter designed to remove dispersion errors that result from the advection of discontinuities (e.g., material interfaces) by high-order, minimally dissipative schemes. The filter introduces no additional diffusion error. Nonuniform viscosity across a material interface is allowed for by the implementation of a compositionally weighted-inverse interface viscosity scheme. The combined method approaches the optimal accuracy of modern shock-capture techniques with a minimal increase in computational time and memory. A key advantage of this method is its simplicity to incorporate into preexisting codes be they finite difference, element, or volume of two or three dimensions.

Lenardic, A.; Kaula, W. M.

1993-01-01

87

Bootstrapping in a high dimensional but very low sample size problem  

E-print Network

High Dimension, Low Sample Size (HDLSS) problems have received much attention recently in many areas of science. Analysis of microarray experiments is one such area. Numerous studies are on-going to investigate the behavior of genes by measuring...

Song, Juhee

2006-08-16

88

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

SciTech Connect

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.

Winters, W.S.

1985-10-01

89

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

ERIC Educational Resources Information Center

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

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

2007-01-01

90

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

ERIC Educational Resources Information Center

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

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

2009-01-01

91

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

ERIC Educational Resources Information Center

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.

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

2007-01-01

92

Effects of Importance and Detectability of Usability Problems on Sample Size Requirements  

Microsoft Academic Search

Existing models of usability evaluation estimate sample size requirements based on goal discovery rate and detectability of potential problems without consideration of the importance of the problem and an index of usability, which allows the comparison of the effectiveness of usability of information technology products and services across different domains. This article presents a methodology which accounts for the aforementioned

April Savoy; Yinni Guo; Gavriel Salvendy

2009-01-01

93

Exact image method for Gaussian beam problems involving a planar interface  

NASA Technical Reports Server (NTRS)

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.

Lindell, I. V.

1987-01-01

94

Exact-image method for Gaussian-beam problems involving a planar interface  

NASA Technical Reports Server (NTRS)

The exact-image method, recently introduced for the solution of electromagnetic field problems involving sources above a planar interface between 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 theory described here 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.

Lindell, Ismo V.

1987-01-01

95

The k-Sample Problem When k is Large and n Small  

E-print Network

The k-sample problem, i.e., testing whether two or more data sets come from the same population, is a classic one in statistics. Instead of having a small number of k groups of samples, this dissertation works on a large number of p groups...

Zhan, Dongling

2012-07-16

96

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

NASA Technical Reports Server (NTRS)

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.

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

1976-01-01

97

Lab on Pointers in C This lab involves playing with a number of C programs to solve some problems involving pointers. There are  

E-print Network

involving pointers. There are 4 different problems, work on as many as you can. If you are a pointer guru, because it points to memory not allocated to your program */ return 0; } #12;Exercise 4 /* p4.c swap, try your hand at the segvhunt (exercise 5). Exercise 5 goes beyond what we expect you to know

98

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

PubMed

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

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

2014-08-01

99

An appraisal of certain problems involved in the use of steroid compounds for contraception.  

PubMed

The problems of oral contraception considered are: possible carcinogenesis, thrombophlebitis or thromboembolism, and possible effect on the reproductive or genetic potential of the ova. Estrogen-progestogen combinations produce characteristic effects of estrogen, indicating that the estrogen given exceeds normal endogenous estrogen production. In humans all known carcinogenic agents involve a latent period, many for a decade or more. Both endogenous and exogenous estrogens have been shown to modify the activity of established breast cancer in humans. The effect on the preclinical phases is unknown. Effects of prolonged use of estrogens on breast cancer will require more extensive studies. Endometrial cancer has been reported to undergo regression under intensive progesterone therapy. Other known carcinolytic agents such as X-rays and alkylating substances are known to be carcinogenic under some conditions. One may, therefore, question the advisability of derangement of such endocrinological relationships. Distinctive histological changes in the endometrium after use of estrogen-progestogen mixtures have been described. Such atrophic changes represent drug-induced pathology. Although these changes disappear when therapy is discontinued, the latent effect is unknown. Since the pathogenic period for cancer of the cervix is estimated to be 7-10 years, studies of this possible effect should exceed this time span and be carefully devised so that data can be compared. Data reported so far do not provide a sound statistical basis. Immediate effects on cervical dysplasia have not been shown to be unfavorable. Thrombophlebitis and thromboembolic phenomena have been reported but on the basis of available data no significant increase in risk has been demonstrated. Studies of carcinogenesis in animals are readily reproduced. However, the human population is so heterogenous that the genetic factor is uncertain. The ultimate effect of oral contraceptives on the ova is unknown. So far observations have shown none. Each physician prescribing these drugs should evaluate the risks involved with due regard for the results of alternate methods of contraception available. PMID:12255250

Hertz, R

1966-01-01

100

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

ERIC Educational Resources Information Center

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

Walitzer, Kimberly S.; Dermen, Kurt H.

2004-01-01

101

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

ERIC Educational Resources Information Center

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

Jewett, John W., Jr.

2008-01-01

102

Factorial dimensions of the Revised Behavior Problem Checklist: Replication and validation within a kindergarten sample  

Microsoft Academic Search

The factor structure of the Revised Behavior Problem Checklist (RBPC) was examined in a large sample of suburban kindergarten children. Teacher-rated dimensions of Conduct Disorder, Attention Problems-Immaturity, Anxiety-Withdrawal, and Psychotic Behavior were closely replicated, and a new factor labeled Unmotivated-Isolated was also revealed. These principal components were consistent across gender and across subsamples of children differing as to risk status

Stephen P. Hinshaw; Delmont C. Morrison; Estol T. Carte; Carol Cornsweet

1987-01-01

103

Sampling  

NSDL National Science Digital Library

This webpage contains three activities that have students work through problems associated with sampling. Each activity includes a brief description, materials list, and a set of lesson worksheets. The last activity on the page, the "Cereal Toy Investigation" also includes an online simulator in the form of a Java applet.

Kawas, Terry

2012-01-01

104

Application of conjugate gradient method for static problems involving conductors of arbitrary shape  

NASA Astrophysics Data System (ADS)

In this paper, two implementations of the Conjugate Gradient Method (CGM) for the solution of problems in electrostatics involving conductors of arbitrary shapes have been discussed. The first method uses a least squares approximation for the computation of the pertinent integral operator and is referred to as LSD. A second implementation, referred to as Point Matching Discretisation (PMD) effects considerable saving in the computer time since it uses the midpoint rule for the integral arising in LSD. Both these techniques require O(N) storage, where N is the number of patches used to model the conductor. Further, a matrix interpretation of the present formulation has been derived. This has facilitated the comparison of the techniques described in this paper with the well known Method of Moments (MoM) formulation and has led to better understanding of the convergence of the results. Using illustrative examples of canonical (square and circular discs) and arbitrary shape (a pyramid mounted on a cube), the convergence of and the computer time for both the implementations have been investigated. It has been shown that both the techniques yielded monotonically convergent results for all the examples considered and that the LSD offers better estimate of the capacitance than PMD with lower number of patches.

Sanjaynath, V. V.; Balakrishnan, N.; Nagabhushana, G. R.

1994-07-01

105

An infinite swapping approach to the rare-event sampling problem  

NASA Astrophysics Data System (ADS)

We describe a new approach to the rare-event Monte Carlo sampling problem. This technique utilizes a symmetrization strategy to create probability distributions that are more highly connected and, thus, more easily sampled than their original, potentially sparse counterparts. After discussing the formal outline of the approach and devising techniques for its practical implementation, we illustrate the utility of the technique with a series of numerical applications to Lennard-Jones clusters of varying complexity and rare-event character.

Plattner, Nuria; Doll, J. D.; Dupuis, Paul; Wang, Hui; Liu, Yufei; Gubernatis, J. E.

2011-10-01

106

Problem behavior in a community sample of 14- and 19-month-old children  

PubMed Central

Few studies have examined the presence, structure, and stability of behavior problems in a community sample of 14- and 19-month-old infants. A questionnaire with items on emotional, attentional, and impulsive behavior and social communication was completed by the parents of 6,491 infants aged 14months and 1,803 infants aged 19months. Particularly externalizing behavior problems were reported to present sometimes or often for 50% of more of the sample and could be considered as common. In contrast, social communication problems were reported to be present in less than 10% of the sample. Overall, boys showed more problem behaviors than girls. Principal component analysis at the 14months data revealed seven factors, which could all be replicated in the 19months data. Pearson correlations between scores at 14months and 19months were highest for oppositional and attention factors (0.68 and 0.63) and lowest for the inhibiton factor (0.38). More than 50% of those scoring in the top 10% for total problem score at 14months were in the top 10% at 19months. These results will facilitate the recognition of psychopathology at very early age and the study of its development over time. PMID:17417714

Swinkels, Sophie H. N.; Buitelaar, Jan K.

2007-01-01

107

Psychopathic Subtypes and Associations with Mental Health Problems in an Incarcerated Sample of Adolescent Boys  

Microsoft Academic Search

Research suggests a distinction between high and low anxious psychopathic individuals. However, research on psychopathic subtypes in youth offender populations is largely lacking. Therefore, this study examined psychopathic subtypes in a sample of incarcerated adolescents, and explored the relationship of these subtypes with various (mental health) problems. The Youth Psychopathic traits Inventory was used to measure psychopathic traits in a

Violaine C. Veen; Henrik Andershed; Gonneke W. J. M. Stevens; Theo A. H. Doreleijers; Wilma A. M. Vollebergh

2011-01-01

108

THE TWO-SAMPLE PROBLEM FOR POISSON PROCESSES: ADAPTIVE TESTS WITH A  

E-print Network

THE TWO-SAMPLE PROBLEM FOR POISSON PROCESSES: ADAPTIVE TESTS WITH A NON-ASYMPTOTIC WILD BOOTSTRAP APPROACH By Magalie Fromont, B´eatrice Laurent and Patricia Reynaud-Bouret CREST (Ensai) - IRMAR (Universit critical val- ues are constructed from a non-asymptotic wild bootstrap approach, leading to level tests

Paris-Sud XI, Université de

109

A Study on Three Linear Discriminant Analysis Based Methods in Small Sample Size Problem  

Microsoft Academic Search

In this paper, we make a study on three linear discriminant analysis (LDA) based methods: regularized discriminant analysis (RDA), discriminant common vectors (DCV) and maximal margin criterion (MMC) in the small sample size (SSS) problem. Our contributions are that: (1) we reveal that DCV obtains the same projection subspace as both RDA and wMMC (weighted MMC, a general form of

Jun Liu; Songcan Chen; Xiaoyang Tan

2008-01-01

110

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

ERIC Educational Resources Information Center

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

Brown, Tamala P.

2012-01-01

111

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

Microsoft Academic Search

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

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

2007-01-01

112

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

PubMed

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

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

2013-12-01

113

Finite-element/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems  

SciTech Connect

Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are both made more viable by replacing large complex computer models with fast-running accurate and noiseless approximations. A Finite Element/Lattice Sampling (FE/LS) methodology for constructing progressively refined finite element response surfaces that reuse previous generations of samples is described here. Similar finite element implementations can be extended to N-dimensional problems and/or random fields and applied to other types of structured sampling paradigms, such as classical experimental design and Gauss, Lobatto, and Patterson sampling. Here the FE/LS model is applied in a ``decoupled`` Monte Carlo analysis of two sets of probability quantification test problems. The analytic test problems, spanning a large range of probabilities and very demanding failure region geometries, constitute a good testbed for comparing the performance of various nondeterministic analysis methods. In results here, FE/LS decoupled Monte Carlo analysis required orders of magnitude less computer time than direct Monte Carlo analysis, with no appreciable loss of accuracy. Thus, when arriving at probabilities or distributions by Monte Carlo, it appears to be more efficient to expend computer-model function evaluations on building a FE/LS response surface than to expend them in direct Monte Carlo sampling.

Romero, V.J.; Bankston, S.D.

1998-03-01

114

Alcohol and Drug Problems in Ontario Physicians: Characteristics of the Physician Sample  

PubMed Central

Thirty-six Ontario physicians who entered a treatment process for alcohol and drug problems were systematically assessed prior to treatment. The demographic and medical practice characteristics of this sample are delineated and, where possible, are compared to those of all Ontario physicians. Physicians with alcohol and drug problems were both similar to and different from all Ontario physicians. Further study is needed to explore the similarities and differences between the two groups, with a view to improving treatment, prevention and professional goverance. PMID:21267194

Glaser, Frederick B.; Brewster, Joan M.; Sisson, Barry V.

1986-01-01

115

Childhood Peer Relationship Problems and Young People's Involvement with Deviant Peers in Adolescence  

Microsoft Academic Search

Using prospective longitudinal data from the Christchurch Health and Development Study, this article examined the relationship between children's peer relationship problems in middle childhood and their subsequent risk of forming deviant peer affiliations in adolescence. The analysis proceeded in three steps. First, a structural equation model demonstrated a moderate association between early peer relationship problems and later deviant peer affiliations

David M. Fergusson; Lianne J. Woodward; L. John Horwood

1999-01-01

116

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

ERIC Educational Resources Information Center

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

Kauffman, James M.; Hallahan, Daniel P.

2009-01-01

117

Profiles of systems involvement in a sample of high-risk urban adolescents with unmet treatment needs  

Microsoft Academic Search

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

Sarah Dauber; Aaron Hogue

2011-01-01

118

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

NASA Technical Reports Server (NTRS)

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

Pohorille, Andrew

2006-01-01

119

High dimensional model representation (HDMR) coupled intelligent sampling strategy for nonlinear problems  

NASA Astrophysics Data System (ADS)

High-dimensional model representation (HDMR) is a general set of metamodel assessment and analysis tools to improve the efficiency of high dimensional underlying system behavior. Compared with the current popular modeling methods, such as Kriging (KG), radial basis function (RBF), and the moving least square approximation method (MLS), the distinctive characteristic of the HDMR is to decouple the input variables. Therefore, a high dimensional problem can be transformed as a low, middle or combination of middle dimensional function. Although the HDMR is a feasible method for high dimensional problems, the computational cost is still a bottleneck for complex engineering problems. To improve the efficiency of the HDMR method further, the purpose of this study is to use an intelligent sampling method for the HDMR. Because the HDMR cannot be integrated with the sampling method directly, a projection-based intelligent method is suggested. Compared with the popular HDMR methods, the construction procedure for the HDMR-based model is optimized. To validate the performance of the suggested method, multiple mathematical test functions are given to illustrate the modeling principles, procedures, and the efficiency and accuracy of HDMR models with problems of a wide scope of dimensionalities.

Li, Enying; Wang, Hu; Li, Guangyao

2012-09-01

120

Polygenic scores predict alcohol problems in an independent sample and show moderation by the environment.  

PubMed

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

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

2014-01-01

121

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

NASA Technical Reports Server (NTRS)

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.

Brenner, Paul

1932-01-01

122

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

PubMed Central

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

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

2007-01-01

123

Problem solving and creativity for undergraduate engineers: findings of an action research project involving robots  

Microsoft Academic Search

Many researchers have written about the importance and complexities of developing problem solving skills and encouraging creative thinking in engineering students. Research continues to suggest deficiencies in developing or assessing process skills; with the attention of engineering educators being on outcomes or products of problem solving scenarios.\\u000d\\u000aThis paper considers highlights of this previous work, and how this might inform

J. P. Adams; S. Turner; S. Kaczmarczyk; P. Picton; P. Demian

2008-01-01

124

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

ERIC Educational Resources Information Center

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

Hallarman, Prudence R.; And Others

125

Abstract--A major problem among the elderly involves falling. The recognition of falls from video first requires the  

E-print Network

Abstract--A major problem among the elderly involves falling. The recognition of falls from video should result in a silhouette that is a binary map indicating only the body position of the individual in an image. We have previously demonstrated a segmentation method based on color that can recognize

He, Zhihai "Henry"

126

The Administrative Problems Involved in Executing Clinical Recommendations for the Treatment of Severe Reading Disorders Within an Ongoing Educational System.  

ERIC Educational Resources Information Center

Developing a program of treatment for dyslexic readers involves four major problems: (1) definition of the reading isability, (2) administrative and educational inertia, (3) organization of the treatment program, and (4) the need for evaluatio and research. There is great disagreement over definitions of reading disabilities, yet an effective

Schiffman, Gilbert B.

127

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

ERIC Educational Resources Information Center

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

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

2007-01-01

128

Water-art problems at SanssouciEulers involvement in practical hydrodynamics on the eve of ideal flow theory  

NASA Astrophysics Data System (ADS)

Frederick the Great blamed Euler for the failure of fountains at his summer palace Sanssouci. However, what is regarded as an example for the proverbial gap between theory and practice, is based on dubious evidence. In this paper I review Eulers involvement with pipeflow problems for the Sanssouci water-art project. Contrary to the widespread slander, Eulers ability to cope with practical challenges was remarkable. The Sanssouci fountains did not fail because Euler was unable to apply hydrodynamical theory to practice, but because the King ignored his advice and employed incompetent practitioners. The hydrodynamics of the Sanssouci problem also deserves some interest because it happened on the eve of the formulation of the general equations of motion for ideal fluids. Although it seems paradoxical, the birth of ideal flow theory was deeply rooted in Eulers involvement with real flow problems.

Eckert, M.

2008-08-01

129

Use of the designation "shedder" in mucosal detection of herpes simplex virus DNA involving repeated sampling  

PubMed Central

Objectives We evaluated two methods to describe detection of HSV from the genital mucosa. Methods We assessed genital swabs from HSV-2 seropositive persons participating in longitudinal studies of HSV DNA detection at the University of Washington Virology Research Clinic. We determined the length of observation period necessary to ensure some HSV detection for most persons. We compared two measures to assess differences in shedding according to HIV status, the shedding rate ratio, defined as the proportion of total samples with detectable HSV in HIV-1 seropositive versus HIV-1 seronegative persons, and the ratio of "shedders", defined as the proportion of persons with any shedding over the interval in HIV-1 seropositive versus HIV-1 seronegative persons. Results While only 17% (51/308) of HSV-2 seropositive persons shed on their first day on study, 77% (238/308) had some genital shedding over 30 days (any HSV DNA detected on genital swabs). Shedding rate ratios for HIV-seropositive versus HIV-seronegative persons varied from SRR=1.42 using 10 samples to SRR=1.35 using 50 samples. The ratio of "shedders" approached 1 as the observation period increased (RS=1.13 using 10 samples to RS=1.01 using 50 samples). In a hypothetical case, the ratio of "shedders" was shown to exceed one when shedding rates were equal. Conclusions Most HSV-2 seropositive persons shed HSV from the genital mucosa. Dichotomization of persons into shedders and nonshedders or high and low shedders yields inferences that depend upon sampling interval length. Overall shedding rates provide consistent measures regardless of the number of swabs collected. PMID:19211593

Magaret, Amalia S.; Johnston, Christine; Wald, Anna

2009-01-01

130

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

PubMed Central

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

2014-01-01

131

Adolescent Predictors of Young Adult and Adult Alcohol Involvement and Dysphoria in a Prospective Community Sample of Women  

Microsoft Academic Search

The adolescent predictors of later alcohol involvement (AI), dysphoria (D), and their shared association (AD) among women have not been adequately established. Three waves of data from an ethnically diverse community sample of women, assessed over 16 years are used to study how various psychosocial factors in adolescence influenced later drinking, depression, and their shared association. Structural equation models revealed

Thomas F. Locke; Michael D. Newcomb

2004-01-01

132

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

ERIC Educational Resources Information Center

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

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

2007-01-01

133

Interval-Valued Optimization Problems Involving (?, ?)-Right Upper-Dini-Derivative Functions  

PubMed Central

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

2014-01-01

134

Well-posed elliptic Neumann problems involving irregular data and domains  

Microsoft Academic Search

Non-linear elliptic Neumann problems, possibly in irregular domains and with data affected by low integrability properties, are taken into account. Existence, uniqueness and continuous dependence on the data of generalized solutions are established under a suitable balance between the integrability of the datum and the (ir)regularity of the domain. The latter is described in terms of isocapacitary inequalities. Applications to

Angelo Alvino; Andrea Cianchi; Vladimir G. Maz'ya; Anna Mercaldo

2010-01-01

135

Abstract--This paper addresses the problem of controlling wind energy conversion systems (WECS) which involve  

E-print Network

Abstract-- This paper addresses the problem of controlling wind energy conversion systems (WECS-inverter. The goal of control is to maximize wind energy extraction and this needs letting the wind turbine rotor wind energy extraction) only for one wind speed value depending on the considered value of turbine

Paris-Sud XI, Université de

136

Does Involvement of Mental Health Consultants with Teachers Change Their Attitudes Toward Children with Emotional Problems?  

ERIC Educational Resources Information Center

The purpose of the practicum was to determine if a specifically designed inservice training program for teachers would change their attitudes toward children suffering from emotional instability. Two groups of teachers from two schools acted as experimental and control groups for the purpose of analysis. The experimental group was involved in an

Mobley, Charles F.

137

Numerical solution of initial boundary value problems involving maxwell's equations in isotropic media  

Microsoft Academic Search

Maxwell's equations are replaced by a set of finite difference equations. It is shown that if one chooses the field points appropriately, the set of finite difference equations is applicable for a boundary condition involving perfectly conducting surfaces. An example is given of the scattering of an electromagnetic pulse by a perfectly conducting cylinder.

KANE S. YEE

1966-01-01

138

The importance of problem formulations in risk assessment: a case study involving dioxin-contaminated soil.  

PubMed

The need to remediate contaminated soils is typically accomplished by applying standard risk assessment methods followed by risk management to select remedial options. These human health risk assessments (HHRAs) have been largely conducted in a formulaic manner that relies heavily on standard deterministic exposure, toxicity assumptions and fixed mathematical formulas. The HHRA approach, with its traditional formulaic practice, does not take advantage of problem formulation in the same manner as is done in ecological risk assessment, and historically, has generally failed to emphasize incorporation of site-specific information. In response to these challenges, the National Academy of Sciences recently made several recommendations regarding the conduct of HHRAs, one of which was to begin all such assessments with problem formulation. These recommendations have since been extended to dose response assessment. In accordance with these recommendations, a group of experts presented and discussed findings that highlighted the importance and impact of including problem formulation when determining the need for remediation of dioxin contamination in soils, focusing in particular on exposure assessment is described. PMID:23545073

Dourson, Michael L; Gadagbui, Bernard; Griffin, Susan; Garabrant, David H; Haws, Laurie C; Kirman, Christopher; Tohyama, Chiharu

2013-07-01

139

Multiparticle correlations in complex scattering and the mesoscopic Boson Sampling problem  

E-print Network

We consider the many-body scattering of non-interacting identical particles in mesoscopic chaotic cavities. A complete enumeration of all interfering paths allows us to discriminate single-particle effects from many-body interference due to quantum indistinguishability. In the thermodynamic limit of large particle number massive quantum interference results in a macroscopic, coherent manifestation of many-body correlations. We also incorporate mesoscopic dephasing, present even when the particles scatter simultaneously. Under further simplifications characteristic for optical scenarios, our methods can be used to address open issues related to the Boson Sampling problem.

Juan-Diego Urbina; Jack Kuipers; Quirin Hummel; Klaus Richter

2014-09-04

140

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

NASA Astrophysics Data System (ADS)

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.

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

2004-05-01

141

Problems in detection of cytomegalovirus in urine samples by dot blot hybridization.  

PubMed Central

A hybridization assay for the detection of cytomegalovirus (CMV) in urine specimens was established. Two different DNA fragments were used as hybridization probes: the HindIII L fragment (11.7 kilobases) and the EcoRI J fragment (10.6 kilobases) of the human CMV strain AD169. These probes were used in an isolated and highly purified form and therefore did not cross hybridize with vector sequences. As shown by hybridization with DNA from CMV-infected and uninfected cells, the assay was highly CMV specific and sensitive (detection limit, 750 to 500 fg of CMV DNA). A total of 122 urine specimens were examined by DNA hybridization, virus isolation, and the detection of CMV-induced early nuclear protein. The results coincided in 91% of the samples. The application of DNA hybridization to urine samples, however, is not without problems, and some of the pitfalls and drawbacks are discussed. Images PMID:2822765

Augustin, S; Popow-Kraupp, T; Heinz, F X; Kunz, C

1987-01-01

142

An examination of dependence power, father involvement, and judgments about violence in an at-risk community sample of mothers.  

PubMed

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 to a relationship with the father of her child. We also considered the influence of perceived father involvement in the child's life on judgments related to dependence power. Using a survey design with a sample of 100 mothers (age: 16-43, M = 29.16, SD = 7.17 years old) enrolled in a local Early Head Start/Head Start program, we observed that a mother's perceived father involvement was positively associated with judgments of her dependence power. Furthermore, we observed that her assessment of dependence power was negatively associated with her tolerance for both physical and psychological violence as well as the use of destructive child discipline tactics. PMID:21859752

Samp, Jennifer A; Abbott, Leslie

2011-12-01

143

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

PubMed Central

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 mothers responsiveness and for adolescents school performance and self-control. Theoretical and practical implications are discussed. PMID:19290687

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

2009-01-01

144

Movie exposure to alcohol cues and adolescent alcohol problems: a longitudinal analysis in a national sample.  

PubMed

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. (PsycINFO Database Record (c) 2009 APA, all rights reserved). PMID:19290687

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

2009-03-01

145

Adolescent criminal justice involvement and adulthood sexually transmitted infection in a nationally representative US sample.  

PubMed

Criminal justice involvement (CJI) disrupts social and sexual networks, and sexually transmitted infections (STIs) thrive on network disruption. Adolescent CJI may be a particularly important determinant of STI because experiences during adolescence influence risk trajectories into adulthood. We used Wave III (2001-2002: young adulthood) of the National Longitudinal Study of Adolescent Health (N?=?14,322) to estimate associations between history of adolescent (younger than 18years) CJI and adult STI risk. Respondents who reported a history of repeat arrest in adolescence, adolescent conviction, and arrest both as an adolescent and an adult (persistent arrest) had between two to seven times the odds of STI (biologically confirmed infection with chlamydia, gonorrhea, or trichomoniasis) in adulthood and between two to three times the odds of multiple partnerships and inconsistent condom use in the past year in adulthood. In analyses adjusting for sociodemographic and behavioral factors, history of having six or more adolescent arrests was associated with more than five times the odds of STI (adjusted odds ratio (AOR) 5.44, 95% confidence interval (CI) 1.74-17.1). Both adolescent conviction and persistent CJI appeared to remain independent correlates of STI (conviction: AOR 1.90, 95% CI 1.02-3.55; persistent CJI: AOR 1.60, 95% CI 0.99-2.57). Adolescents who have repeat arrests, juvenile convictions, and persist as offenders into adulthood constitute priority populations for STI treatment and prevention. The disruptive effect of adolescent CJI may contribute to a trajectory associated with STI in adulthood. PMID:22815054

Khan, Maria R; Rosen, David L; Epperson, Matthew W; Goldweber, Asha; Hemberg, Jordana L; Richardson, Joseph; Dyer, Typhanye Penniman

2013-08-01

146

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

NASA Technical Reports Server (NTRS)

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.

Anderson, Richard

1987-01-01

147

Sampling  

NSDL National Science Digital Library

This tutorial covers some of the key terms in sampling like "population" and "sampling frame," some of the statistical terms used in sampling, and the major distinction between probability and Nonprobability sampling methods.

William Trochim (Cornell University)

2006-10-20

148

Sampling riverine sediments impacted by acid mine drainage: problems and solutions  

Microsoft Academic Search

Sampling acid mine drainage (AMD) or natural acid rock drainage (ARD)-impacted sediments is complex, requiring appropriate\\u000a field sampling techniques to ensure representative samples that are both repeatable and reproducible. The important factors\\u000a affecting sampling of riverine sediments are examined. These include sample site location, field observations, representative\\u000a sampling, sample collection techniques, and sample preservation. A recommended sampling and processing protocol

C. Herr; N. F. Gray

1997-01-01

149

Weighted piecewise LDA for solving the small sample size problem in face verification.  

PubMed

A novel algorithm that can be used to boost the performance of face-verification methods that utilize Fisher's criterion is presented and evaluated. The algorithm is applied to similarity, or matching error, data and provides a general solution for overcoming the "small sample size" (SSS) problem, where the lack of sufficient training samples causes improper estimation of a linear separation hyperplane between the classes. Two independent phases constitute the proposed method. Initially, a set of weighted piecewise discriminant hyperplanes are used in order to provide a more accurate discriminant decision than the one produced by the traditional linear discriminant analysis (LDA) methodology. The expected classification ability of this method is investigated throughout a series of simulations. The second phase defines proper combinations for person-specific similarity scores and describes an outlier removal process that further enhances the classification ability. The proposed technique has been tested on the M2VTS and XM2VTS frontal face databases. Experimental results indicate that the proposed framework greatly improves the face-verification performance. PMID:17385635

Kyperountas, Marios; Tefas, Anastasios; Pitas, Ioannis

2007-03-01

150

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

PubMed Central

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 1217 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

Pilowsky, Daniel J; Wu, Li-Tzy

2006-01-01

151

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

NASA Technical Reports Server (NTRS)

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.

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

1999-01-01

152

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

PubMed Central

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

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

2009-01-01

153

Energy drink use, problem drinking and drinking motives in a diverse sample of Alaskan college students  

PubMed Central

Background Recent research has identified the use of caffeinated energy drinks as a common, potentially risky behavior among college students that is linked to alcohol misuse and consequences. Research also suggests that energy drink consumption is related to other risky behaviors such as tobacco use, marijuana use and risky sexual activity. Objective This research sought to examine the associations between frequency of energy drink consumption and problematic alcohol use, alcohol-related consequences, symptoms of alcohol dependence and drinking motives in an ethnically diverse sample of college students in Alaska. We also sought to examine whether ethnic group moderated these associations in the present sample of White, Alaska Native/American Indian and other ethnic minority college students. Design A paper-and-pencil self-report questionnaire was completed by a sample of 298 college students. Analysis of covariance (ANCOVA) was used to examine the effects of energy drink use, ethnic group and energy drink by ethnic group interactions on alcohol outcomes after controlling for variance attributed to gender, age and frequency of binge drinking. Results Greater energy drink consumption was significantly associated with greater hazardous drinking, alcohol consequences, alcohol dependence symptoms, drinking for enhancement motives and drinking to cope. There were no main effects of ethnic group, and there were no significant energy drink by ethnic group interactions. Conclusion These findings replicate those of other studies examining the associations between energy drink use and alcohol problems, but contrary to previous research we did not find ethnic minority status to be protective. It is possible that energy drink consumption may serve as a marker for other health risk behaviors among students of various ethnic groups. PMID:23986901

Skewes, Monica C.; DeCou, Christopher R.; Gonzalez, Vivian M.

2013-01-01

154

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

ERIC Educational Resources Information Center

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

Boxer, Paul

2011-01-01

155

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

ERIC Educational Resources Information Center

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

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

2005-01-01

156

The Comparative Impacts of Risk and Protective Factors on Alcohol-Related Problems in a Sample of University Students  

Microsoft Academic Search

The purpose of this study was to examine the comparative influences of various protective and risk factors on the alcohol-related problems of a sample of university students. The conceptualization of these protective and risk factors in the current undertaking was informed by problem behavior theory, and draws heavily on two sociological theories of deviant behavior (social learning theory and social

Keith F. Durkin; Amber Blackston; Sabrina Dowd; Shalleigh Franz; Trevor Eagle

2009-01-01

157

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

ERIC Educational Resources Information Center

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

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

2007-01-01

158

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

PubMed Central

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. Childrens 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. Childrens 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 grandchildrens 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

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

2011-01-01

159

Analysis of Korean High School Students' Decision-Making Processes in Solving a Problem Involving Biological Knowledge  

NASA Astrophysics Data System (ADS)

In this study, the cognitive characteristics of students'' decision-making processes centered on phases, difficulties, and strategies are analysed in the personal dailylife context involving biological knowledge. The subjects were first year science and general high school students in Seoul, Korea; 6 female students and 7 male students. The students'' decision-making processes were analysed by think-aloud and participant observation methods. On the whole, the students'' decision-making processes progressed in following order: recognizing a problem, searching for alternatives, evaluating the alternatives, and decision. During the decision-making processes, the above phases were repeated by trial and error. Students preferred noncompensatory rules that did not allow trade offs among alternatives for decisions, rather than compensatory rules of selection. Students had a tendency to have difficulties in analysing the difference between initial state and desirable state of the problem, organising biological knowledge-related problems, and clarifying values as selective criteria. Even students who had high achievement and more positive science-related attitudes did not apply biological knowledge to search for alternatives, and could not utilise scientific values as selective criteria very well. We discuss the implications of these results for teaching of decision-making in respect to scientific literacy.

Hong, Jung-Lim; Chang, Nam-Kee

2004-02-01

160

Predictors of reported current and lifetime substance abuse problems among a national sample of U.S. homeless.  

PubMed

Using the National Survey of Homeless Assistance Providers and Clients (NSHAPC), this study examined predictors of alcohol and drug problems among a national probability sample of homeless and previously homeless adults in the United States. Consistent with research, about one third and one quarter of the respondents reported a current alcohol and drug problem, respectively. A larger proportion reported lifetime substance abuse problems. As hypothesized, males, younger respondents, veterans, and those with mental and physical health problems were at greater risk. Results reveal that substance abuse treatment and prevention programs for the homeless should take into consideration these characteristics to maximize effectiveness. PMID:17934993

Dietz, Tracy L

2007-01-01

161

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

PubMed Central

We investigated longitudinal associations between alcoholic fathers 12-step treatment involvement and their childrens internalizing and externalizing problems (N=125, Mage=9.83.1), testing the hypotheses that fathers greater treatment involvement would benefit later child behavior, and that this effect would be mediated by fathers post-treatment behaviors. The initial association was established between fathers treatment involvement and childrens externalizing problems only, while structural equation (SEM) results supported mediating hypotheses. Fathers greater treatment involvement predicted childrens lower externalizing problems 12 months later, and fathers post-treatment behaviors mediated this association: greater treatment involvement predicted greater post-treatment Alcoholics Anonymous (AA) attendance, which in turn predicted greater abstinence. Finally, fathers abstinence was associated with lower externalizing problems in children. Theoretical and practical implications of these findings are discussed. PMID:18715745

Andreas, Jasmina Burdzovic; O'Farrell, Timothy J

2008-01-01

162

Agreement Between Parents and Teachers on Preschool Children's Behavior in a Clinical Sample with Externalizing Behavioral Problems.  

PubMed

An accurate interpretation of information obtained from multiple assessors is indispensible when complex diagnoses of behavioral problems in children need to be confirmed. The present study examined the similarity of parents and kindergarten teachers ratings on children's behavior in a sample of 160 preschool children (a clinical group including 80 children with externalizing behavioral problems and a matched control group including 80 children). Behavioral problems were assessed using the SDQ, and the DISYPS-II questionnaires for ADHD and conduct disorders. The results revealed low levels of parent-teacher agreement for their ratings on the children's behavior in both groups with the highest correlations in the non-clinical sample. Parent-teacher agreement did not differ significantly across the samples. Parent and teacher ratings correlated with the prevalence of externalizing disorders and were found to be almost independent of each other. The results highlight the importance of multiple informants and their independent influence within the diagnostic process. PMID:24363143

Korsch, Franziska; Petermann, Franz

2014-10-01

163

Eating Problems and the Self-Concept: Results Based on a Representative Sample of Norwegian Adolescent Girls  

Microsoft Academic Search

The joint role of self-esteem and unstable self-perceptions for eating problems was investigated in a representative Norwegian population sample of girls in 3 age groups (N = 5287; aged 1219 years). Three scales from the 12-item Eating Attitudes Test (EAT-12) measured eating problems: Restriction, Bulimia-food preoccupation, and Diet. Girls low on all EAT scales were most often characterized by high

Juliska Kansi; Lars Wichstrm; Lars R. Bergman

2003-01-01

164

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

Microsoft Academic Search

The longitudinal stability of eating problems and their relationships to risk factors were investigated in a representative\\u000a population sample of 623 Norwegian girls aged 1314 followed over 7 years (3 time points). Three eating problem symptoms were\\u000a measured: Restriction, Bulimia-food preoccupation, and Diet, all taken from the12-item Eating Attitudes Test. The aim of the\\u000a study was to investigate the stability

Juliska Kansi; Lars Wichstrm; Lars R. Bergman

2005-01-01

165

A Regularized Sampling Method for Solving Three-Dimensional Inverse Scattering Problems  

Microsoft Academic Search

. The inverse scattering problem under consideration is to determine theshape of an obstacle in R3from a knowledge of the time harmonic incident acousticwave and the far field pattern of the scattered wave with frequency in the resonanceregion. A method for solving this nonlinear and improperly posed problem is presentedwhich is based on solving a linear integral equation of the

David Colton; Klaus Giebermann Peter Monk; Peter Monk

2000-01-01

166

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

PubMed Central

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

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

2012-01-01

167

Emotional and behavioural problems in a sample of Finnish three-year-olds.  

PubMed

Behavioural and emotional problems in Finnish three-year-olds was studied using the Child Behavior Checklist for ages 2-3 as a standardised rating scale at well-baby clinics in two cities in Finland. Altogether 374 questionnaires were analysed which is 71% of the target population. When compared with studies from other countries the mean scores and prevalences of preschool children's problem behaviours were rather similar. Boys were reported to be more destructive than girls. Parental education level, living in one-parent family and parental unemployment were associated with a higher level of problem behaviours. No significant differences were found in emotional or behavioural problems related to the child's day care. Co-sleeping with parents was associated with sleep problems. PMID:11469289

Sourander, A

2001-06-01

168

Problem Drinking, Unemployment, and Intimate Partner Violence among a Sample of Construction Industry Workers and their Partners  

Microsoft Academic Search

The purpose of this study is to determine the contribution of male unemployment and each partners problem drinking to risk\\u000a for male-to-female partner violence (MFPV) and female-to-male partner violence (FMPV) among a sample of construction industry\\u000a workers and their spouses\\/partners. Participants in the sample (n = 848 couples) completed cross-sectional health behavior surveys. Multivariate logistic regression models of MFPV and

Carol B. Cunradi; Michael Todd; Michael Duke; Genevieve Ames

2009-01-01

169

A sample path approach for solving the ground-holding policy problem in air traffic control  

Microsoft Academic Search

We address the ground-holding problem in air traffic control and propose two techniques that can be used to dynamically solve this problem. The first is motivated by the kanban control policy extensively used in manufacturing systems to reduce the work-in-process inventory, while the second one uses finite perturbation analysis (FPA) for discrete-event systems. We show that the latter leads to

Christos G. Panayiotou; Christos G. Cassandras

1999-01-01

170

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

ERIC Educational Resources Information Center

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

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

2010-01-01

171

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

ERIC Educational Resources Information Center

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

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

2013-01-01

172

Grid-based Evolutionary Strategies Applied to the ConformationalSampling Problem  

Microsoft Academic Search

Computational simulations of conformational sampling in general, and of macromolecular folding in particular represent one of the most important and yet one of the most challenging applications of computer science in biology and medicinal chemistry. The advent of GRID computing may trigger some major progress in this field. This paper presents our first attempts to design GRID-based conformational sampling strategies,

Benjamin Parent; Alexandru-adrian Tantar; Nouredine Melab; El-ghazali Talbi; Dragos Horvath

2007-01-01

173

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

ERIC Educational Resources Information Center

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

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

2002-01-01

174

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

ERIC Educational Resources Information Center

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.

Ozmutlu, Ilker

2014-01-01

175

Drug driving and the management of risk: The perspectives and practices of a sample of problem drug users  

Microsoft Academic Search

This paper reports on a qualitative study of the attitudes and risk management strategies of a sample of problem drug users in relation to driving while under the influence of drugs. Interviews were conducted with 26 individuals (21 men and 5 women) all of whom had been addicted to heroin and had admitted to driving while under the influence of

James McIntosh; Tommy OBrien; Neil McKeganey

2008-01-01

176

UPDATED USER-FRIENDLY COMPUTER PROGRAMS FOR SOLVING SAMPLING AND STATISTICAL PROBLEMS (FOR MICROCOMPUTERS) (DATE OF COVERAGE: 1993). - SOFTWARE.  

EPA Science Inventory

The product contains user-friendly computer programs for solving sampling and related statistical problems. All have been updated as well and more programs have been added. Specific, detailed written instructions and examples built into the programs are provided so that the user ...

177

Assessing problems of organic hydroperoxide-induced chemiluminescence related to biological/medical samples.  

PubMed

The supernatants obtained from mammalian tissue homogenates, blood serum or other body fluids, and supplemented with organic hydroperoxide show a multiplicity of light-emitting reactions. The low-level chemiluminescence of biological samples denotes that after hydroperoxide-induction electronically excited species are produced. The light-emission measured by photomultipliers is related to (i) the geometrical location of the induced sample, (ii) light gathering capacity of the phototubes, and (iii) both the quantity and concentration of samples and reactants. The fewest blood contamination of biological samples leads to an increased photoemission. The very high sensitivity of light detectors requires stable measuring and sampling conditions and peculiarly cautious evaluation of the reactions. PMID:15560941

Trk, B

2004-10-29

178

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

PubMed

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

Surez, B; Lope, V; Prez-Gmez, B; Aragons, N; Rodrguez-Artalejo, F; Marqus, F; Guzmn, A; Viloria, L J; Carrasco, J M; Martn-Moreno, J M; Lpez-Abente, G; Polln, M

2005-11-01

179

[Technical problems in the preparation of biopsy samples of the spleen].  

PubMed

Spleen tissue sampling for bioptical examination should be performed after mutual consultation of clinician and pathologist. Clinician should know what is expected from the pathologist. This can influence preparation and sampling method considerably. In a great amount of cases the whole organ is removed. A lab technician is sampling on her own and her contribution to a good result can be either positive or negative. Imprint preparations from the tissue sections can be useful. Specialized examination should be performed in the presence of a pathologist or his co-workers. The active approach of a lab technician can significantly contribute to the value of examined sample of the spleen, of the organ until recently considered to be not important or full of mysteries. PMID:9560894

Jakubovsk, V; Porubsk, J; Trnka, J; Durdk, S; Zajckov, M; Kollrov, E; Balzov, K

1996-02-01

180

The problem of large samples: An activation analysis study of electronic waste material  

Microsoft Academic Search

Large-volume instrumental photon activation analysis (IPAA) was used for the investigation of shredded electronic waste material.\\u000a Sample masses from 1 to 150 grams were analyzed to obtain an estimate of the minimum sample size to be taken to achieve a\\u000a representativeness of the results which is satisfactory for a defined investigation task. Furthermore, the influence of irradiation\\u000a and measurement parameters

C. Segebade; P. Bode; W. Goerner

2007-01-01

181

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

PubMed Central

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

2009-01-01

182

The Linear Sampling Method for Solving the Electromagnetic Inverse Scattering Problem  

Microsoft Academic Search

We consider the inverse scattering problem of determining the shape of an obstaclein R3from a knowledge of the time harmonic incident electromagnetic wave and the far eld patternof the scattered wave with frequency in the resonance region. The approach used is the linearsampling method which does not require a priori knowledge of either the boundary condition or theconnectivity of the

David Colton; Houssem Haddar; Peter Monk

2003-01-01

183

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

ERIC Educational Resources Information Center

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%])

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

2010-01-01

184

Finite-element\\/progressive-lattice-sampling response surface methodology and application to benchmark probability quantification problems  

Microsoft Academic Search

Optimal response surface construction is being investigated as part of Sandia discretionary (LDRD) research into Analytic Nondeterministic Methods. The goal is to achieve an adequate representation of system behavior over the relevant parameter space of a problem with a minimum of computational and user effort. This is important in global optimization and in estimation of system probabilistic response, which are

V. J. Romero; S. D. Bankston

1998-01-01

185

PROBLEMS OF EDUCATIONAL EVALUATION IN PROJECT HEAD START--SAMPLING, DESIGN, AND CONTROL GROUPS.  

ERIC Educational Resources Information Center

CONTRARY TO THE OPINION OF MANY PEOPLE, PROJECT HEADSTART (HS) IS NOT A STABLE AND UNIFORM PROGRAM WHICH DEALS WITH AN EASILY DEFINABLE POPULATION. THERE ARE, THEREFORE, SEVERAL PROBLEMS WHICH EXIST IN CONNECTION WITH EVALUATIVE RESEARCH CONCERNED WITH HS. IN ORDER TO PROVIDE GUIDANCE IN PROGRAM PLANNING, THIS RESEARCH SEEKS TO DESCRIBE POTENTIAL

MCDAVID, JOHN W.

186

Constructivist, Problem-Based Learning Does Work: A Meta-Analysis of Curricular Comparisons Involving a Single Medical School  

ERIC Educational Resources Information Center

Effects of problem-based learning as reported in curricular comparison studies have been shown to be inconsistent over different medical schools. Therefore, we decided to summarize effects of a single well-established problem-based curriculum rather than to add up sometimes-conflicting findings from different problem-based curricula. Effect sizes

Schmidt, Henk G.; van der Molen, Henk T.; te Winkel, Wilco W. R.; Wijnen, Wynand H. F. W.

2009-01-01

187

Gambling behavior subtypes among respondents with gambling-related problems in a population-based sample.  

PubMed

Latent class analysis was used to delineate distinctive subgroups of gamblers and examine whether they differed by demographics and gambling severity. Data from three Canadian provinces focused on respondents who reported at least some risk of problem gambling in the past year (N=1,071). Three latent classes were distinguished: a low on most items group (class 1), a behaviorally conditioned/substance abusing impulsive/emotionally vulnerable (or all types) group (class 2), and a familial-genetic/behaviorally conditioned group (class 3). Gamblers in classes 2 and 3 were most likely to be moderate-risk and problem gamblers. Community-based prevention efforts may need to address each subgroup differently but also according to their characteristics. PMID:21491298

Martins, Silvia S; Ghandour, Lilian A; Storr, Carla L

2011-04-01

188

PROBLEMS WITH A NAFION (TRADE NAME) MEMBRANE DRYER FOR DRYING CHROMATOGRAPHIC SAMPLES  

EPA Science Inventory

A Nafion membrane dryer was used to dry samples of organic gases emitted by vegetation before chromatographic separation to reduce water-related retention time variations on a fused-silica column. The dryer caused rearrangement of several monoterpenes and removed several importan...

189

Magnetic Polarity Stratigraphy: Stochastic Properties of Data, Sampling Problems, and the Evaluation of Interpretations  

Microsoft Academic Search

A statistical model has been derived which can be used either to test the interpretation of a given magnetic stratigraphy or to make time estimates from the paleomagnetic data. The model is based on the presently accepted statistical properties of the earth's magnetic field and the stochastic nature of the paleomagnetic sampling process. Given knowledge of the number of paleomagnetic

Noye M. Johnson; Victor E. McGee

1983-01-01

190

Magnetic polarity stratigraphy: Stochastic properties of data, sampling problems, and the evaluation of interpretations  

Microsoft Academic Search

A statistical model has been derived which can be used either to test the interpretation of a given magnetic stratigraphy or to make time estimates from the paleomagnetic data. The model is based on the presently accepted statistical properties of the earth's magnetic field and the stochastic nature of the paleomagnetic sampling process. Given knowledge of the number of paleomagnetic

Noye M. Johnson; Victor E. McGee

1983-01-01

191

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

PubMed

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

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

2014-01-01

192

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

USGS Publications Warehouse

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.

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

1996-01-01

193

The flavor problem of soybean oil. III. A four-sample, glass laboratory deodorizer  

Microsoft Academic Search

SummaryA glass laboratory deodorizer has been described which permits the simultaneous deodorization of four samples under nearly\\u000a identical conditions of time, temperature, pressure and rate of steam flow. The design includes provision for measuring and\\u000a controlling the steam flow, for preventing bumping, for breaking the vacuum, and for heating and cooling the deodorizer.\\u000a Successful deodorizations have been made in relatively

Arthur W. Schwab; Herbert J. Dutton

1948-01-01

194

Inference Procedures for One Sample and Paired-Data Location Problems  

E-print Network

in the large-sample case z1-/2 is selected from the standard normal distribution. · hypothesis test for H0 : µ = µ0 Reject H0 if X - µ0 s/ n too large (1-sided test against µ > µ0) or if X - µ0 s/ n too large (2-sided test against µ = µ0) · efficiency: High if F is truly normal in shape. Very poor, however, even

Serfling, Robert

195

Non-Erotic Thoughts, Attentional Focus, and Sexual Problems in a Community Sample  

Microsoft Academic Search

According to Barlows model of sexual dysfunction, anxiety in sexual situations leads to attentional focus on sexual performance\\u000a at the expense of erotic cues, which compromises sexual arousal. This negative experience will enhance anxiety in future sexual\\u000a situations, and non-erotic thoughts (NETs) relevant to performance will receive attentional priority. Previous research with\\u000a student samples (Purdon & Holdaway, 2006; Purdon &

Andrea L. Nelson; Christine Purdon

2011-01-01

196

The consolidation characteristics of undisturbed soil samples of deep formations and their application to problems of regional subsidence  

E-print Network

THE CONSOLIDATION CHARACTERISTICS OF UNDISTURBED SOII SAMPLES OF DEEP FORMATIONS AND THEIR APPLICATION TO PROBLEMS OF REGIONAL SUBSIDENCE LYLE ANTHONY WOLFSKILL Submitted to the Graduate School of the Agricultural and Mechanical College... OF REGIONAL SUBSIDENCE LYIZ ANTHONY WOLFSKILL Approved as to style and content hy: (C airman f Committee) (Head of Depar ent) ACKNONLEDGEMENTS The author is sincerely grateful for the tireless and expert leadership provided by Mr. Spencer J. Buchanan...

Wolfskill, Lyle Anthony

2012-06-07

197

Ten-Year Comparisons of Problems and Competencies for National Samples of YouthSelf, Parent, and Teacher Reports  

Microsoft Academic Search

The Youth Self-Report (YSR;Achenbach, 1995),Child Behavior Checklist (CBCL;Achenbach,2001),and Teacher's Report Form (TRF; Achenbach & Rescorla, 2001) were used to compare U.S. national samples of 11- to 18-year-olds assessed in 1989 and 1999. Reports by all informants concurred in showing small improvements in competencies and adaptive functioning and small declines in problems from 1989 to 1999. Correlations of .98 to .99

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

2002-01-01

198

Teacher and parent perceptions of behavior problems among a sample of African American, Hispanic, and non-Hispanic white students.  

PubMed

A multiracial/multiethnic sample of middle school adolescents and their teachers was used to assess whether teacher ratings of student behavior problems varied according to teacher-student racial/ethnic differences and students' perception of teachers' attitudes toward them. No significant mean score differences were found for Hispanic or non-Hispanic white students according to the race/ethnicity of the teachers doing the ratings. However, African American students rated by Hispanic and non-Hispanic white teachers had significantly higher mean total behavior problem scores than African American students rated by African American teachers. Teacher ratings were also compared to those made by parents. The percentage of students rated as cases by teachers but not by parents differed significantly by race/ethnicity of student. Other findings indicated highly significant relationships between student-perceived teacher disparagement and the assignment of high behavior problem scores to students by teachers. PMID:7572829

Zimmerman, R S; Khoury, E L; Vega, W A; Gil, A G; Warheit, G J

1995-04-01

199

Interpersonal problems across restrictive and binge-purge samples: data from a community-based eating disorders clinic.  

PubMed

Contemporary models of eating disorders suggest that interpersonal problems contribute to the maintenance of eating disorders. This study examined whether baseline interpersonal problems differed across eating disorder diagnoses and across eating disorder subtypes ("restrictors" vs. "binge-purge" patients) in a large clinical sample. Patients with a primary eating disorder diagnosis (N=406) completed measures of interpersonal problems, eating disorder symptoms, and mood prior to treatment at a specialist eating disorder clinic. Across the sample, more severe eating disorder psychopathology was associated with significantly greater difficulty socializing. Anorexia Nervosa (AN)/restrictor patients reported significantly greater difficulty socializing than Bulimia Nervosa (BN)/binge-purge patients. AN patients reported significantly greater difficulty on a measure of competitiveness/assertiveness compared to BN and Eating Disorder Not Otherwise Specified patients. All findings were significant after controlling for comorbid depression and anxiety symptoms. Interpersonal problems appear to be unique risk factors for eating disorders. Specific interpersonal mechanisms include difficulties socializing and being assertive, which were most pronounced in AN patients. These findings provide potential avenues for enhancing interventions, such as adjunctive assertiveness training for AN. PMID:25064298

Raykos, Bronwyn C; McEvoy, Peter M; Carter, Olivia; Fursland, Anthea; Nathan, Paula

2014-08-01

200

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

PubMed Central

Children with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for the development of depression, with evidence that peer and academic difficulties mediate predictions of later depression from ADHD. The present study hypothesized that parent-child relationship difficulties may be an additional potential mediator of this association. Academic, peer, and parent-child functioning were tested as mediators of the association of attention problems and depression in two distinctly different, yet complementary samples. Study 1 was a cross-sectional sample of 230 510 year-old children with and without ADHD. Study 2 was a prospective longitudinal sample of 472 youth followed prospectively from birth to age 20 at risk for depression. Despite differences in age, measures, and designs, both studies implicated peer and parent-child problems as unique mediators of depressive symptoms, although academic difficulties did not uniquely mediate the ADHD-depression association. Further, inattention symptoms, but not hyperactivity, predicted depressive symptoms via the disruption of interpersonal functioning. The inclusion of oppositional defiant disorder into models impacted results, and supported its independent role in parent-child problems. Implications include support for interventions that target interpersonal competence, which may effectively reduce the risk of depression among children with ADHD. PMID:24016021

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

2013-01-01

201

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

NASA Technical Reports Server (NTRS)

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.

Tamma, Kumar K.; Namburu, Raju R.

1989-01-01

202

Betweenness Ordering Problem : An Efficient Non-Uniform Sampling Technique for Large Graphs  

E-print Network

Centrality measures, erstwhile popular amongst the sociologists and psychologists, has seen wide and increasing applications across several disciplines of late. In conjunction with the big data problems there came the need to analyze big networks and in this connection, centrality measures became of great interest to the community of mathematicians, computer scientists and physicists. While it is an important question to ask how one can rank vertices based on their importance in a network, there hasn't been a commonly accepted definition, mainly due to the subjectivity of the term "importance". Amongst a plethora of application specific definitions available in the literature to rank the vertices, closeness centrality, betweenness centrality and eigenvector centrality (page-rank) have been the most important and widely applied ones. In the current paper, we formulate a method to determine the betweenness ordering of two vertices without exactly computing their betweenness indices - which is a daunting task fo...

Agarwal, Manas; Chaudhary, Shubham; Iyengar, Sudarshan

2014-01-01

203

Two-stage k-sample designs for the ordered alternative problem.  

PubMed

In preclinical studies and clinical dose-ranging trials, the Jonckheere-Terpstra test is widely used in the assessment of dose-response relationships. Hewett and Spurrier (1979) presented a two-stage analog of the test in the context of large sample sizes. In this paper, we propose an exact test based on Simon's minimax and optimal design criteria originally used in one-arm phase II designs based on binary endpoints. The convergence rate of the joint distribution of the first and second stage test statistics to the limiting distribution is studied, and design parameters are provided for a variety of assumed alternatives. The behavior of the test is also examined in the presence of ties, and the proposed designs are illustrated through application in the planning of a hypercholesterolemia clinical trial. The minimax and optimal two-stage procedures are shown to be preferable as compared with the one-stage procedure because of the associated reduction in expected sample size for given error constraints. PMID:22408050

Shan, Guogen; Hutson, Alan D; Wilding, Gregory E

2012-01-01

204

Mental Health and the Experience of Social Problems Involving Rights: Findings from the United Kingdom and New Zealand  

Microsoft Academic Search

As with general morbidity, psychiatric morbidity has been linked to an array of social problems, with interest in those links heightened by the noted vulnerability of those with mental illness and the cost of mental illness to the economy. Legal rights have a bearing upon many social problems. This study, based on data drawn from surveys of 2,628 adults in

Pascoe Pleasence; Nigel J. Balmer

2009-01-01

205

Genetic and environmental influences on lifetime alcohol-related problems in a volunteer sample of older twins.  

PubMed

Few studies have employed genetically informative designs to study the causes of alcohol-related problems in nonclinical populations. We report patterns of alcohol abuse in a community-based U.S. volunteer sample of 3,049 female and 1,070 male twins aged 50 to 96. Significant gender and age effects were found for self-report measures of current and lifetime alcohol-related problems, with higher prevalence among males and lower frequency among older birth cohorts. Significant associations were found between severity of alcohol abuse (adapted from Feighner criteria) and age of drinking onset, parental history of alcohol problems and, among males, lower educational attainment. Model-fitting analyses based on data from 650 identical and 479 fraternal twin pairs indicate substantial family resemblance for a variety of definitions of lifetime alcohol abuse and alcohol problems. The median estimate of genetic variance across several definitions of alcohol problems was 38.5%, while that for shared environmental influence was 15.5%. Gender heterogeneity was not found for magnitude of genetic and environmental influences, but these comparisons were limited by low statistical power. Findings are discussed with reference to the literature on alcohol abuse among older adults and the genetic epidemiology of alcoholism. PMID:8189739

Prescott, C A; Hewitt, J K; Truett, K R; Heath, A C; Neale, M C; Eaves, L J

1994-03-01

206

A Linear Sampling Method for Near-Field Inverse Problems in Elastodynamics Bojan Guzina, Sylvain Nintcheu Fata, and Andrew Madyarov | Civil Engineering, University of Minnesota  

E-print Network

A Linear Sampling Method for Near-Field Inverse Problems in Elastodynamics Bojan Guzina, Sylvain the frame- work of a linear sampling method. @ Applications Homeland security Environmental remediation Linear sampling method · Fast · No initial guess @ Linear sampling method in literature Acoustics

Guzina, Bojan

207

Looking back into one magazine's online presence raises questions about the problems involved with creating web archives  

NSDL National Science Digital Library

Survey Finds That Libraries Are Interested in Collaborating on Online Projects, but Don't Do It Yethttp://www.theatlantic.com/technology/archive/2012/07/survey-finds-that-libraries-are-interested-in-collaborating-on-online-projects-but-dont-do-it-yet/259486/Neatline helps Map New World of Digital Humanities Scholarshiphttp://www.virginia.edu/uvatoday/newsRelease.php?id=19012Neatlinehttp://neatline.org/Internet Archivehttp://archive.org/index.phpInternet Memory Foundationhttp://internetmemory.org/en/Many people might wonder: "Who is keeping track of old webpages?" It is a question that fascinates many information science specialists, policy types, and those with a penchant for the history of technology. Recently the "Babbage" column in The Economist took a look around to explore the history of that august publication's own webpages. As it turns out, their first website went live in early 1994, and it cost a mere $120. The piece goes on to note that no screen shots actually exist of the world's first web page, which went online on August 6, 1991. Of course, there are many worthy projects that serve to document the early days of the Internet, such as the well-known and rather fun Wayback Machine. It was founded by Brewster Kahle, and it allows users to view the library's archived webpages as they appeared when first published online. On a related note, a recent post on The Atlantic's homepage remarked that while 96% of all libraries surveyed by the Library of Congress wanted to be involved in various web archiving projects, only 23% were actually doing it. Many organizations have some type of archiving project for formal documents, but they lag behind when it comes to archiving social media activities, such as Twitter or Facebook posts. The first link will take visitors to the very fine piece from The Economist which peers into that magazine's early online presence. The second link leads to the aforementioned piece by Robinson Meyer from The Atlantic which reports on collaborations between libraries. Moving on, the third link leads to a story from the University of Virginia about the new Neatline project, which allows interested parties to "merge maps, timelines, archives, and artifacts to create online narratives" for free. The fourth link will take users to the homepage of Neatline. Here they can view sample projects and download the software for their own use. The fifth link will whisk visitors to the homepage of the most remarkable Internet Archive, which contains digitized medieval manuscripts, Grateful Dead shows, and curious industrial films. The final link leads to the homepage of the Internet Memory Foundation, which "actively supports the preservation of the Internet as a new media for heritage and cultural purpose."

Grinnell, Max

2012-07-13

208

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

ERIC Educational Resources Information Center

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

Samp, Jennifer A.; Abbott, Leslie

2011-01-01

209

Development of a branch and price approach involving vertex cloning to solve the maximum weighted independent set problem  

E-print Network

We propose a novel branch-and-price (B&P) approach to solve the maximum weighted independent set problem (MWISP). Our approach uses clones of vertices to create edge-disjoint partitions from vertex-disjoint partitions. We solve the MWISP on sub...

Sachdeva, Sandeep

2006-04-12

210

Global Nonparametric Sufficient Optimality Conditions for Semi-Infinite Discrete Minmax Fractional Programming Problems Involving Generalized (?, ?)-Invex Functions  

Microsoft Academic Search

In this paper, we establish a set of necessary optimality conditions and discuss a fairly large number of sets of global nonparametric sufficient optimality criteria under various generalized (?, ?)-invexity assumptions for a minmax fractional programming problem with infinitely many nonlinear inequality and equality constraints.

G. J. Zalmai; Qinghong Zhang

2007-01-01

211

A Longitudinal Examination of the Relationship between Adolescent Problem Behaviors and Traffic Crash Involvement during Young Adulthood  

Microsoft Academic Search

Previous research examining the relationship between adolescent problem behaviors and young adult traffic outcomes (crashes, convictions, risky driving) has produced differing results. Possible reasons for this may be the heterogeneity of the crash outcomes (from minor fender-benders to fatal crashes), the gender of the driver, and\\/or the age of the driver. The aim of this research was to investigate the

Dorothy J. Begg; Pauline Gulliver

2008-01-01

212

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

ERIC Educational Resources Information Center

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

Mason, W. Alex; Spoth, Richard L.

2011-01-01

213

On Involvement.  

ERIC Educational Resources Information Center

Involvement Ratings In Settings (IRIS), a multi-dimensional non-verbal scale of involvement adaptable to a time-sampling method of data collection, was constructed with the aid of the videotapes of second-grade Follow Through classrooms made by CCEP. Scales were defined through observations of involved and alienated behavior, and the IRIS was

Greene, Michael B.

214

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

NASA Astrophysics Data System (ADS)

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.

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

2000-12-01

215

Negative-energy states in the Dirac-Hartree-Fock problem - The effect of omission of two-electron integrals involving the small component  

NASA Technical Reports Server (NTRS)

The effect of omission of two-electron integrals involving basis functions for the small component of the wavefunction on the eigenvalue spectrum in the Dirac-Hartree-Fock problem is studied. From an analysis of the Fock matrix it is shown that omission of these integrals moves the negative-energy states down, not up. Their complete omission does not give rise to intruder states. The appearance of intruder states occurs when only some of the core integrals are omitted, due to the nature of particular contraction schemes used for the core basis functions. Use of radially localized functions rather than atomic functions alleviates the intruder state problem.

Dyall, Kenneth G.

1992-01-01

216

Psychopathological status, behavior problems, and family adjustment of Kuwaiti children whose fathers were involved in the first gulf war  

Microsoft Academic Search

OBJECTIVES: Following the end of the Gulf War that resulted in the liberation of Kuwait, there are no reports on the impact of veterans' traumatic exposure and posttraumatic stress disorder (PTSD) on their children. We compared the severity of anxiety, depression, deviant behavior and poor family adjustment among the children of a stratified random sample of four groups of Kuwaiti

Fawziyah A Al-Turkait; Jude U Ohaeri

2008-01-01

217

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

PubMed Central

Glucan particles (GPs) are 24 ?m hollow, porous shells composed of 1,3-?-D-glucan that have been effectively used for oral targeteddelivery 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 CD8?- 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 ?-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

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

2014-01-01

218

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

Microsoft Academic Search

Greater empirical attention directed toward gender-sensitive assessment strategies that concentrate on family-specific factors\\u000a is thought to be both timely and necessary, especially with regard to outcome variables associated with mental health and\\u000a substance abuse in at-risk adolescent populations. A sample of 2,646 court-involved adolescents was used to test two competing\\u000a models regarding relationships among disruptive family processes, mental health (as

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

2008-01-01

219

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

NASA Astrophysics Data System (ADS)

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

Sinky, Hussein Mohammed

220

The Child Behavior Checklist, Teacher Report Form and Youth Self Report Problem Scales in a Normative Sample of Croatian Children and Adolescents Aged 7-18  

Microsoft Academic Search

The main goal of this study was to standardize the Child Behavior Checklist (CBCL), Teacher Report Form (TRF) and Youth Self Report (YSR) questionnaire problem scales on a normative random sample of children and adolescents (N=3309) aged 7 to 18 throughout Croatia. The second goal was to compare boys-girls problem scales data and CBCL- TRF-YSR differences in our sample. The

Vlasta Rudan; Ivan Begovac; Lajos Szirovicza; Oleg Filipovi; Milena Sko

221

The Cusp/Core Problem in Galactic Halos: Long-Slit Spectra for a Large Dwarf Galaxy Sample  

E-print Network

We derive inner dark matter halo density profiles for a sample of 165 low-mass galaxies using rotation curves obtained from high-quality, long-slit optical spectra assuming minimal disks and spherical symmetry. For $\\rho(r) \\sim r^{-\\alpha}$ near the galaxy center we measure median inner slopes ranging from $\\alpha_m = 0.22 \\pm 0.08$ to $0.28 \\pm 0.06$ for various subsamples of the data. This is similar to values found by other authors, and in stark contrast to the intrinsic cusps ($\\alpha_{int}\\sim1$) predicted by simulations of halo assembly in cold dark matter (CDM) cosmologies. To elucidate the relationship between $\\alpha_m$ and $\\alpha_{int}$ in our data, we simulate long-slit observations of model galaxies with halo shapes broadly consistent with the CDM paradigm. Simulations with $\\alpha_{int}=1/2$ and 1 recover both the observed distribution of $\\alpha_m$ and correlations between $\\alpha_m$ and primary observational parameters such as distance and disk inclination, whereas those with $\\alpha_{int}=5/4$ are marginally consistent with the data. Conversely, the hypothesis that low-mass galaxies have $\\alpha_{int}=3/2$ is rejected. While the simulations do not imply that the data favor intrinsic cusps over cores, they demonstrate that the discrepancy between $\\alpha_m$ and $\\alpha_{int}\\sim1$ for our sample does not necessarily imply a genuine conflict between our results and CDM predictions: rather, the apparent cusp/core problem may be reconciled by considering the impact of observing and data processing techniques on rotation curves derived from long-slit spectra.

Kristine Spekkens; Riccardo Giovanelli; Martha P. Haynes

2005-02-08

222

The relative effects of maternal and child problems on the quality of attachment: a meta-analysis of attachment in clinical samples.  

PubMed

In this meta-analysis of 34 clinical studies on attachment the hypothesis is tested that maternal problems such as mental illness lead to more deviating attachment classification distributions than child problems such as deafness. A correspondence analysis on 21 North American studies with normal subjects produced a baseline against which the clinical samples could be evaluated. Separate analyses were carried out on studies containing the traditional A, B, C classifications and on studies that also included the recently discovered D or A/C category. Results show that groups with a primary identification of maternal problems show attachment classification distributions highly divergent from the normal distributions, whereas groups with a primary identification of child problems show distributions that are similar to the distributions of normal samples. The introduction of the D or A/C classifications (about 15% in normal samples) reveals an overrepresentation of D or A/C in the child problem groups, but the resulting distribution still is much closer to the normal distributions compared to the samples with maternal problems. In clinical samples, the mother appears to play a more important role than the child in shaping the quality of the infant-mother attachment relationship. PMID:1387067

van Ijzendoorn, M H; Goldberg, S; Kroonenberg, P M; Frenkel, O J

1992-08-01

223

Quantile BEAST (Bootstrap Error-Adjusted Single-Sample Technique) Attacks the False-Sample Problem in Near-Infrared Reflectance Analysis.  

National Technical Information Service (NTIS)

The multiple linear regression approach typically used in near-infrared calibration yields equations in which any amount of reflectance at the analytical wavelengths leads to a corresponding composition value. As a result, when the sample contains a compo...

G. M. Hieftje, R. A. Lodder

1988-01-01

224

Conduct Problem Behaviors in a Stratified Random Sample of Children and Adolescents: New Standardization Data on the Eyberg Child Behavior Inventory  

Microsoft Academic Search

This study presents new standardization data on the Eyberg Child Behavior Inventory (ECBI), a parent-completed measure of conduct-problem behaviors. The ECBI was mailed to the parents of a stratified random sample of 3,600 students in Grades 1 to 12. A total of 1,003 completed ECBIs were returned (28%). Results indicated that the ECBI provides a homogenous measure of conduct-problem behaviors.

G. Leonard Burns; David R. Patterson

1990-01-01

225

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

ERIC Educational Resources Information Center

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

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

2013-01-01

226

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

ERIC Educational Resources Information Center

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,

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

2012-01-01

227

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

Microsoft Academic Search

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;

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

2012-01-01

228

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

PubMed

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

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

2007-03-01

229

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

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

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

2003-01-01

230

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

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

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

2007-01-01

231

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

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

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

2004-01-01

232

BIO 320: Questions from Tests and Problem Sets BIO 564 Students: Consider this document a preview/sample of the ma-  

E-print Network

BIO 320: Questions from Tests and Problem Sets BIO 564 Students: Consider this document a preview/sample of the ma- terial to be discussed and tested during the Spring 2012 semester. 1. A population experiences, or removed. Explain the quantitative concept of a critical population size that emerges when we analyze

Caraco, Thomas

233

The link between ethnicity, social disadvantage and mental health problems in a school-based multiethnic sample of children in the Netherlands.  

PubMed

To investigate to what extent differences in prevalence and types of mental health problems between ethnic minority and majority youth can be explained by social disadvantage. Mental health problems were assessed in a sample of 1,278 schoolchildren (55% Dutch, 32% Moroccan and 13% Turkish; mean age: 12.91.8) using the Strengths and Difficulties Questionnaire self-report and teacher report. Measures of family socioeconomic status, neighbourhood deprivation, perceived discrimination, family structure, repeating a school year, housing stability and neighbourhood urbanization were used as indicators of social disadvantage, based on which a cumulative index was created. Ethnic minority youth had more externalizing and fewer internalizing problems than majority youth. Perceived discrimination and living in an unstable social environment were associated with mental health problems, independent of ethnicity. A dose-response relationship was found between social disadvantage and mental health problems. The adjusted odds ratio for mental health problems was 4.16 (95% CI 2.49-6.94) for more than four compared with zero indicators of social disadvantage. Social disadvantage was more common in ethnic minority than in majority youth, explaining part of the differences in prevalence of mental health problems. Ethnic minority youth in the Netherlands have a different profile of mental health problems than majority youth. In all ethnic groups, the risk of mental health problems increases with the degree of social disadvantage. The higher prevalence of externalizing problems among ethnic minority youth is explained partly by their disadvantaged social position. The findings suggest that social factors associated with ethnicity are likely to explain mental health problems in ethnic groups. PMID:24927803

Adriaanse, Marcia; Veling, Wim; Doreleijers, Theo; van Domburgh, Lieke

2014-11-01

234

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

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

2014-01-01

235

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

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

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

2011-01-01

236

Prevalence of aggression and fear-related behavioral problems in a sample of Argentine Dogos in Italy  

Microsoft Academic Search

The Argentine Dogo breed is identified frequently as potentially dangerous in worldwide legislation. To investigate the prevalence of problem behaviors in this breed, 94 Argentine Dogo owners provided information on aggressive and fearful behaviors shown by their dogs (83 males, 98 females) in a questionnaire. The results were consistent with the origin of the Argentine Dogo (i.e., descending from fighting

Silvana Diverio; Gabriella Tami; Antonino Barone

2008-01-01

237

Reasons for drinking in relation to problem drinking behavior in a sample of Japanese high school students.  

PubMed

To clarify reasons for drinking in relation to problem drinking behavior, 494 male students, aged 15 to 18 years old and attending high schools in Tokyo, Japan, were examined by self-rating questionnaires including the Kuriharna Alcoholism Screening Test (KAST). Three hundred and forty-two students (69%) completed the questionnaires, of whom 143 indicated that they were current drinkers of alcohol (42% of respondents). Of the 143,16 (11%) reported, through the KAST, experience of problem drinking behavior. A factor analysis of 36 reasons for drinking identified 5 factors: Escapism, Sociability, Tension Reduction, Acting Like a Man, and Enjoyment/Home. A logistic regression analysis showed that drinking because of Escapism, Sociability, and Tension Reduction was significantly related to problem drinking behavior. Also, there was significant correlation between the 3 factors and the number of KAST items experienced by the 143 respondents. Our findings suggest that the factors of Escapism, Sociability, and Tension Reduction lead to problem drinking in Japanese high school students. PMID:16250684

Yokoyama, K; Nishikitani, M; Araki, S

1999-01-01

238

Gender-Related Quality of Parent-Child Interactions and Early Adolescent Problem BehaviorsExploratory Study With Midwestern Samples  

Microsoft Academic Search

This article reports two exploratory studies testing a model guided by a social interactional perspective, positing an inverse relation between the quality of parent-child interactions and adolescent problem behaviors. It addresses mixed findings in the literature related to gender differences. Study 1 uses cross-sectional survey data from midwestern parents with either a boy (n = 377) or a girl (n

Richard Spoth; Tricia Neppl; Catherine Goldberg-Lillehoj; Tony Jung; Suhasini Ramisetty-Mikler

2006-01-01

239

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

Microsoft Academic Search

Fast Track is a multisite, multicomponent preventive intervention for young children at high risk for long-term antisocial behavior. Based on a comprehensive developmental model, intervention included a universal-level classroom program plus social skills training, academic tutoring, parent training, and home visiting to improve competencies and reduce problems in a high-risk group of children selected in kindergarten. At the end of

1999-01-01

240

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

ERIC Educational Resources Information Center

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

Hove, Oddbjorn; Havik, Odd E.

2008-01-01

241

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

NASA Technical Reports Server (NTRS)

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

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

1975-01-01

242

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

Microsoft Academic Search

From an original sample of 2454 participants free of self-reported psychological distress, 1463 workers completed a 15-month follow-up. Baseline measures included exposure to job demands, decision latitude, social support and need for recovery. Psychological distress was assessed using the General Health Questionnaire at baseline and at follow-up. The findings showed that medium and high exposure to job demands and social

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

2011-01-01

243

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

Microsoft Academic Search

Responses to Life Satisfaction Scale for Problem Youth (LSSPY) items were exam- ined 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 life\\/dating, use of drugs, use of alcohol, money\\/material possessions, transportation,

Brad Donohue; Gordon Teichner; Nathan Azrin; Noah Weintraub; Thomas A. Crum; Leah Murphy

2003-01-01

244

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

Microsoft Academic Search

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 life\\/dating, use of drugs, use of alcohol, money\\/material possessions, transportation, control

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

2003-01-01

245

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

Microsoft Academic Search

This is the first study to examine the relation between rape and substance use problems in college women as a function of three legally recognized forms of rape: forcible, incapacitated, and substance-facilitated rape. Data were collected via structured telephone interview with a large national sample of college women aged 1834years (n=1980). Lifetime prevalence of any type of rape was 11.3%

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

2009-01-01

246

The concerned significant others of people with gambling problems in a national representative sample in Sweden - a 1 year follow-up study  

PubMed Central

Background Research into the impact of problem gambling on close social networks is scarce with the majority of studies only including help-seeking populations. To date only one study has examined concerned significant others (CSOs) from an epidemiological perspective and it did not consider gender. The aim of this study is to examine the health, social support, and financial situations of CSOs in a Swedish representative sample and to examine gender differences. Methods A population study was conducted in Sweden in 2008/09 (n?=?15,000, response rate 63%). Respondents were defined as CSOs if they reported that someone close to them currently or previously had problems with gambling. The group of CSOs was further examined in a 1-year follow up (weighted response rate 74% from the 8,165 respondents in the original sample). Comparisons were also made between those defined as CSOs only at baseline (47.7%, n?=?554) and those defined as CSOs at both time points. Results In total, 18.2% of the population were considered CSOs, with no difference between women and men. Male and female CSOs experienced, to a large extent, similar problems including poor mental health, risky alcohol consumption, economic hardship, and arguments with those closest to them. Female CSOs reported less social support than other women and male CSOs had more legal problems and were more afraid of losing their jobs than other men. One year on, several problems remained even if some improvements were found. Both male and female CSOs reported more negative life events in the 1year follow-up. Conclusions Although some relationships are unknown, including between the CSOs and the individuals with gambling problems and the causal relationships between being a CSO and the range of associated problems, the results of this study indicate that gambling problems not only affect the gambling individual and their immediate close family but also the wider social network. A large proportion of the population can be defined as a CSO, half of whom are men. While male and female CSOs share many common problems, there are gender differences which need to be considered in prevention and treatment. PMID:24261955

2013-01-01

247

Problem Solving  

NSDL National Science Digital Library

Problem solving is the thought processes involved in solving a problem. It is both a means of developing students' knowledge of mathematics and a critical outcome of a good mathematics education. A mathematical problem, as distinct from an exercise, requires the solver to search for a method for solving the problem rather than following a set procedure. Mathematical problem solving, therefore, requires an understanding of relevant concepts, procedures, and strategies. To become good problem solvers, students need many opportunities to formulate questions, model problem situations in a variety of ways, generalize mathematical relationships, and solve problems in both mathematical and everyday contexts.

K-12 Outreach,

248

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 105, NO. E9, PAGES 22,48722,506, SEPTEMBER 25TH Issues involved in a Martian sample return: Integrity  

E-print Network

for components that come into contact with the samples. The adverse effects of temperature on the samples dead bacteria on the outbound spacecraft and materials that come into contact with the samples during are explored, and it is demonstrated that heat sterilization or undue temperature increases in transit

249

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

NASA Astrophysics Data System (ADS)

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.

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

250

The problem of sampling on built heritage: a preliminary study of a new non-invasive method.  

PubMed

The relevance of a risk assessment of the built heritage was clearly justified due to the fact that it acts as a pollutant repository and hazardous pollutants have the capacity to penetrate into materials. However, the limitation of the sampling processes due to the high value of the built heritage makes a correct evaluation difficult. For that reason, in the present work, the potential of agar gels as non-invasive samplers of built heritage deterioration products, like crusts and patinas, was evaluated. Different gels of agar and Carbopol (as control gel) were applied on these built surfaces considering several factors: the treatment time, the effectiveness of the addition of EDTA (ethylenediaminetetraacetic acid, C10H16N2O8) and its concentration and the use of a buffer at pH7.5. All these factors were evaluated in order to determine the capacity of these gels as sampling systems under non-controlled atmospheric conditions. The results obtained in the assays were evaluated by visual examination, by evolution of pH and by the most important techniques used in the risk assessment analysis of the built heritage (Raman spectroscopy, scanning electron microscope (SEM)/energy dispersive X-ray (EDX) and inductively coupled plasma mass spectrometry (ICP-MS)). In this evaluation, the agar gels showed an intrinsic capacity as sampler with respect to the gel Carbopol and thus, the best option between the studied gels consisted on agar gels with 2% of EDTA and the longest application time. On the whole, the agar gels showed an interesting potential as non-invasive samplers of built heritage deterioration materials which should be studied more in depth. PMID:24946700

Prieto-Taboada, N; Isca, C; Martnez-Arkarazo, I; Casoli, A; Olazabal, M A; Arana, G; Madariaga, J M

2014-11-01

251

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

SciTech Connect

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.

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

2008-08-01

252

Mechanisms Linking Stressful Life Events and Mental Health Problems in a Prospective, Community-Based Sample of Adolescents  

PubMed Central

Purpose Stressful life events represent potent risk factors for the development of internalizing symptoms among adolescents. However the mechanisms linking stress to adolescent psychopathology remain inadequately understood. This study examined the role of emotion dysregulation as a mechanism linking stress to changes in internalizing symptoms among adolescents. Methods This study used a short-term longitudinal design. Stressful life events were assessed in a large diverse sample of adolescents (N = 1065), and emotion dysregulation and symptomatology outcomes were assessed at two subsequent time points. Structural equation modeling was used to examine the role of emotion dysregulation as a mediator of the association between stress and subsequent changes in internalizing symptoms. Results Emotion dysregulation mediated the relationship between stressful life events and changes in internalizing symptoms over time. Sobels test indicated a significant indirect effect of stressful life events on subsequent symptoms of depression (z = 5.05, p < .001) and anxiety (z = 4.95, p < .001) through emotion dysregulation. Conclusions Stressful life events appear to disrupt the adaptive processing of emotion among adolescents. Emotion dysregulation represents an intrapersonal mechanism linking stress to poor mental health outcomes. The implications for preventive interventions are discussed. PMID:19167664

McLaughlin, Katie A.; Hatzenbuehler, Mark L.

2010-01-01

253

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

PubMed

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

Tripodi, Stephen J; Pettus-Davis, Carrie

2013-01-01

254

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)

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.

Neal, Clive R.

2000-09-01

255

Anabolic-Androgenic Steroid Use and Involvement in Violent Behavior in a Nationally Representative Sample of Young Adult Males in the United States  

PubMed Central

We examined the effects of anabolic-androgenic steroid use on serious violent behavior. Multivariate models based on data from the National Longitudinal Study of Adolescent Health (N = 6823) were used to examine the association between lifetime and past-year self-reported anabolic-androgenic steroid use and involvement in violent acts. Compared with individuals who did not use steroids, young adult males who used anabolic-androgenic steroids reported greater involvement in violent behaviors after we controlled for the effects of key demographic variables, previous violent behavior, and polydrug use. PMID:18923108

Vaughn, Michael G.; DeLisi, Matt; Wright, John Paul

2008-01-01

256

Prevalence of sexual problems in Portugal: results of a population-based study using a stratified sample of men aged 18 to 70 years.  

PubMed

Despite the use of different methodologies, target populations, and clinical definitions of sexual problems, recent epidemiological studies have shown that the occurrence of sexual difficulties is a very common experience among men from the general population regardless of their age. The objective of this study was to present epidemiological data on the prevalence of sexual difficulties in a community sample of 650 sexually active Portuguese men, stratified by age, marital status, and educational level. Participants completed a self-reported questionnaire assessing sexual function in the previous four weeks (International Index of Erectile Function). Results showed that sexual difficulties were relatively common among this sample. Rapid ejaculation was the most frequently reported sexual difficulty (23.2%), followed by erectile difficulties (10.2%), orgasm problems (8.2%), and low desire (2.9%) in the previous four weeks. With the exception of rapid ejaculation, all categories showed age-specific prevalence rates, with sexual difficulties increasing gradually in men above age 45. Age was a significant predictor of all sexual difficulties except rapid ejaculation, and lower educational levels were related to orgasm difficulties. Findings are consistent with the majority of epidemiological studies indicating a high prevalence of sexual difficulties among men in the general population and highlight the importance and the need to implement sexual health promotion programs in the target population. PMID:23573897

Quinta Gomes, Ana Lusa; Nobre, Pedro J

2014-01-01

257

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)

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.

Allen, Arthur William

258

Risk and Protective Factors Among African American Adolescent Males That Predict Adult Involvement in the Criminal Justice System: Evidence From a National Sample  

Microsoft Academic Search

The current study examined risk and protective factors in adolescence that predicted involvement in the criminal justice system among young adult African American men. Participants (n= 2,274) drawn from the National Longitudinal Study of Adolescent Health were adolescents (1119 years, M = 15) at Wave 1 and young adults (1827, M = 22) at Wave 3. We examined how racial

Danelle Stevens-Watkins; Scott L. Graves

2011-01-01

259

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

PubMed

In antibiotic residue analyses the first step of screening is just as important as the following steps. Screening methods need to be quick and inexpensive, but above all sensitive enough to detect the antibiotic residue at or below the maximum residue limit (MRL). In the case of a positive result, the next step is conducted and further methods are used for confirmation. MRLs stated in European Union Regulation 37/2010 for tetracyclines in raw milk are: 100gkg(-1) for tetracycline, 100gkg(-1) for oxytetracycline, 100gkg(-1) for chlortetracycline and no limit for doxycycline because it is prohibited for use in animals from which milk is produced for human consumption. The current five-plate microbiological screening method for the detection of antibiotic residues in raw milk was found to be simple and inexpensive, but not specific, sensitive and reliable enough to detect tetracycline at MRL in routine raw milk screening procedures. Spiking samples with tetracycline at the MRL level and applying them on Bacillus cereus ATCC 11778 microbiological plates often gave false-negative results, indicating that tetracyclines may have to be inactivated or masked. Tetracyclines seem to bind to a certain component in milk. Consequently, when applying samples to the B. cereus microbiological plate the antibiotic cannot inhibit the growth of B. cereus which disables the formation of inhibition zones on the test plate. After adding the appropriate amount of citric acid into the milk samples, we solved the problem of false-negative results. During the validation 79 samples of milk were spiked with tetracyclines at different concentrations: 100gkg(-1) for tetracycline, 100gkg(-1) for oxytetracycline, 80gkg(-1) for chlortetracycline and 30gkg(-1) for doxycycline. Concentrations used in the validation matched the requirements for MRLs (they were either at or below the MRLs) stated in European Union Regulation 37/2010. The sensitivity of the validation was 100%. PMID:25230820

Raspor Lain?ek, P; Biasizzo, M; Henigman, U; Dolenc, J; Kirbi, A

2014-11-01

260

Bed Death and Other Lesbian Sexual Problems Unraveled: A Qualitative Study of the Sexual Health of Lesbian Women Involved in a Relationship  

Microsoft Academic Search

Objectives: To shed light on lesbian bed death among lesbian women. To explore the wishes and expectations of lesbian women with respect to healthcare professionals.Methods: Semi-structured interviews with 30 self-identified lesbian women. The interviews were audio recorded. Three researchers classified and analyzed the most important themes.Results: The women indicated few sexual problems except for bed death, a quasi-complete cessation of

K. A. W. L. van Rosmalen-Nooijens; C. M. Vergeer; A. L. M. Lagro-Janssen

2008-01-01

261

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

PubMed Central

Changes in histamine storage in the oxyntic mucosa of duodenal ulcer patients and their reversal by vagotomy and the histamine H2-antagonist cimetidine supported the hypothesis that histamine could be a causal factor in peptic ulcer pathogenesis. The specificity of these findings was impaired by problems in biopsy taking, however, and in the preparative steps before measuring the actual histamine contents in all parts of the gastric mucosa and in the duodenum. A prospective trial was carried out in 190 patients to identify these sources of bias and to overcome them by appropriate study designs. Usually a direct correlation was found between weight of biopsy and mucosal histamine content. This problem was solved by selecting a biopsy forceps producing smaller variations in sample size, by limiting the time of cold ischaemia to four to five minutes only and by taking three biopsy specimens for each single histamine value. The actual histamine content of mucosal biopsies remained constant for about four to five minutes only. The 'disappearance' rate was faster in control subjects than in duodenal ulcer patients. Hence by variation of the cold ischaemia time any artefacts of differences between mucosal histamine levels in controls and duodenal ulcer patients could be produced. Using the optimised sample taking procedure mucosal histamine contents of several gastric regions and the duodenal bulb were measured in 24 patients with duodenal ulcer, after selective proximal vagotomy without drainage and in control subjects without any stomach disease (randomised controlled trial). The histamine content was lower in all parts of the upper gastrointestinal tract in duodenal ulcer patients than in controls and was raised again in all regions after selective proximal vagotomy. As the most likely hypothesis it is suggested that vagal reflexes with afferent fibres coming from the oxyntic mucosa stimulate histamine release in duodenal ulcer patients by efferent peptidergic neurones to all parts of the stomach and the duodenum where the ulcer lesion is situated. PMID:3905529

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

1985-01-01

262

An examination of the underlying influence of temperament and problem behaviors on drinking behaviors in a sample of adult offspring of alcoholics.  

PubMed

The present study investigated the potential mediating influence of childhood and early adolescent temperament and problem behaviors on the relation between parental alcoholism and adult drinking behaviors in a sample of 153 offspring of alcoholics and their controls. The influence of the alcoholic parent's and the offspring's gender on this relation was also assessed. Both gender of the parent and gender of the offspring were found to have important differential effects. More specifically, individuals with an alcoholic father consumed more alcohol, were more concerned about their drinking, and were more concerned about the possibility of developing a drinking problem than those without an alcoholic father. In contrast, no significant relations emerged between maternal alcoholism and drinking behaviors. Gender differences among the offspring were also observed, with males drinking more frequently to "get high" and scoring higher on the MAST than females. Finally, gregariousness was found to significantly mediate the relation between paternal alcoholism and frequency of drinking to "get high" and frequency of drinking to "get drunk" for males. Possible explanations regarding the differential results pertaining to gender and the lack of significant findings concerning mediation are discussed. PMID:7942244

Ohannessian, C M; Hesselbrock, V M

1994-01-01

263

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

PubMed Central

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

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

2011-01-01

264

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

PubMed

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

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

2014-02-01

265

Participation in research involving novel sampling and study designs to identify acute HIV-1 infection among minority men who have sex with men.  

PubMed

HIV-1 infection disproportionally affects African-American and Latino men who have sex with men (MSM). Their inclusion in biomedical and behavioral research is critical to understanding and addressing HIV vulnerability. Using focus groups, we sought to understand the perceptions related to participating in biomedical research of acute/recent HIV-1 infection (AHI) using complex sampling and data collection methods to reach this hidden group at highest risk of acquiring and transmitting HIV. Given the potential impact of AHI on HIV transmission in MSM, it is important to understand this intersection for HIV prevention, care, and treatment purposes. The aim of this study was to understand how recruitment and data collection methods affect AHI research participation willingness particularly among MSM of color. Findings suggest that major barriers to research participation with complex sampling to identify AHI and intensive risk behavior collection such as diary methods are lack of anonymity, partner disclosure, and study fatigue. The authors explore implications for future study designs and development based on these findings. PMID:23305688

Rodriguez, Kristina; Castor, Delivette; Mah, Timothy L; Cook, Stephanie H; Auguiste, Lex M; Halkitis, Perry N; Markowitz, Marty

2013-01-01

266

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

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

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

2013-01-01

267

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?  

Microsoft Academic Search

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

Arthur William Allen

1998-01-01

268

Predicting child behavior problems in maritally violent families  

Microsoft Academic Search

Previous research indicates that children from violent marriages are more likely to suffer from conduct problems and\\/or anxiety disorders than children from nonviolent, satisfactory marriages. However, knowledge regarding specific factors present in violent marriages relating to child problems is limited. The present study examined the relationships involving interspousal aggression, parent-child aggression, and child behavior problems in a sample of 45

Ernest N. Jouriles; Julian Barling; K. Daniel O'Leary

1987-01-01

269

Reflections on meta-analyses involving trials stopped early for benefit: is there a problem and if so, what is it?  

PubMed

We review controversies associated with randomized controlled trials (RCTs) stopped early for apparent benefit (truncated RCTs or tRCTs) and present our groups' perspective. Long-established theory, simulations and recent empirical evidence demonstrate that tRCTs will on average overestimate treatment effects, and this overestimation may be large, particularly when tRCTs have small number of events. Theoretical considerations and simulations demonstrate that on average, meta-analyses of RCTs with appropriate stopping rules will lead to only trivial overestimation of treatment effects. However, tRCTs will disproportionally contribute to meta-analytic estimates when tRCTs occur early in the sequence of trials with few subsequent studies, publication of nontruncated RCTs is delayed, there is publication bias, or tRCTs result in a 'freezing' effect in which 'correcting' trials are never undertaken. To avoid applying overestimates of effect to clinical decision-making, clinicians should view the results of individual tRCTs with small sample sizes and small number of events with skepticism. Pooled effects from meta-analyses including tRCTs are likely to overestimate effect when there is a substantial difference in effect estimates between the tRCTs and the nontruncated RCTs, and in which the tRCTs have a substantial weight in the meta-analysis despite themselves having a relatively small number of events. Such circumstances call for sensitivity analyses omitting tRCTs. PMID:22170891

Bassler, Dirk; Montori, Victor M; Briel, Matthias; Glasziou, Paul; Walter, Stephen D; Ramsay, Tim; Guyatt, Gordon

2013-04-01

270

Three-Year Course of Behavioral\\/Emotional Problems in a National Sample of 4- to 16-Year-Olds: 3. Predictors of Signs of Disturbance  

Microsoft Academic Search

We tested parent-reported family variables, problems, competencies, and stress as predictors of (a) academic problems, (b) school behavior problems, (c) receipt of mental health services, (d) child's need for additional help, (e) suicidal behavior, (f) police contacts, and (g) the sum of these 6 outcomes. Included in the study were 995 cases manifesting at least 1 sign of disturbance (from

Catherine Stanger; Thomas M. Achenbach; Stephanie H. McConaughy

1993-01-01

271

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

PubMed Central

Background Little is known about the stability of behavioural and developmental problems as children develop from infants to toddlers in the general population. Therefore, we investigated behavioural profiles at two time points and determined whether behaviours are stable during early development. Methods Parents of 4,237 children completed questionnaires with 62 items about externalizing, internalizing, and social-communicative behaviour when the children were 1415 and 3637 months old. Factor mixture modelling identified five homogeneous profiles at both time points: three with relatively normal behaviour or with mild/moderate problems, one with clear communication and interaction problems, and another with pronounced negative and demanding behaviour. Results More than 85% of infants with normal behaviour or mild problems at 1415 months were reported to behave relatively typically as toddlers at 3637 months. A similar percentage of infants with moderate communication problems outgrew their problems by the time they were toddlers. However, infants with severe problems had mild to severe problems as toddlers, and did not show completely normal behaviour. Improvement over time occurred more often in children with negative and demanding behaviour than in children with communication and interaction problems. The former showed less homotypic continuity than the latter. Conclusions Negative and demanding behaviour is more often transient and a less specific predictor of problems in toddlerhood than communication and interaction problems. PMID:25061477

2014-01-01

272

Fundamental problems in color vision. I. The principle governing changes in hue, saturation, and lightness of non-selective samples in chromatic illumination  

Microsoft Academic Search

Non-selective samples in chromatic illumination have been shown to exhibit the color of the illuminant, the color of the after-image complementary to the illuminant, or achromaticity, depending upon the relation of the reflectance of the sample to the adaptation reflectance. Change of background has been found sufficient to shift the color of a sample from the illuminant color to achromaticity

H. Helson

1938-01-01

273

Some inverse problems involving conditional expectations  

Microsoft Academic Search

Let ([Omega], F, P) be a probability space, let H be a sub-[sigma]-algebra of F, and let Y be positive and H-measurable with E[Y] = 1. We discuss the structure of the convex set CE(Y; H) = {X [set membership, variant] pF: Y = E[XH]} of random variables whose conditional expectation given H is the prescribed Y. Several characterizations of

A. F. Karr

1981-01-01

274

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

PubMed Central

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

2013-01-01

275

Toddler behavioral problems and parent-child interaction in an inner-city early intervention sample: Implications for assessment and intervention  

Microsoft Academic Search

Behavior problems among very young children referred for early intervention services are a common concern. Given that serious problems tend to persist over time, placing children at risk for later personal and social maladjustment, it is important to identify early maladaptive patterns and intervene effectively. Several evolving contemporary developmental formulations that draw on empirical findings converge on the importance of

Jessica Linnell Hopkins

2001-01-01

276

Family Involvement.  

ERIC Educational Resources Information Center

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

Liontos, Lynn Balster

1992-01-01

277

Problem Solving  

Microsoft Academic Search

This paper proposes, characterizes and outlines the benefits of a new computer level specifically for multi-agent problem solvers. This level is called the cooperation knowledge level and involves describing and developing richer and more explicit models of common social phenomena. We then focus on one particular form of social interaction in which groups of agents decide they wish to work

Nick Jennings

1967-01-01

278

Influence of early regulatory problems in infants on their development at 12 months: a longitudinal study in a high-risk sample  

PubMed Central

Background This study examined the extent to which regulatory problems in infants at 4 and 6months influence childhood development at 12months. The second aim of the study was to examine the influence maternal distress has on 4-month-old childrens subsequent development as well as gender differences with regard to regulatory problems and development. Methods 153 mother-child dyads enrolled in the family support research project Nobody slips through the net constituted the comparison group. These families faced psychosocial risks (e.g. poverty, excessive demands on the mother, and mental health disorders of the mother, measured with the risk screening instrument Heidelberger Belastungsskala - HBS) and maternal stress, determined with the Parental Stress Index (PSI-SF). The childrens developmental levels and possible early regulatory problems were evaluated by means of the Ages and Stages Questionnaires (ASQ) and a German questionnaire assessing problems of excessive crying along with sleeping and feeding difficulties (SFS). Results A statistically significant but only low, inverse association between excessive crying, whining and sleep problems at 4 and 6months and the social development of one-year-olds (accounting for 5% and 8% of the variance respectively) was found. Feeding problems had no effect on development. Although regulatory problems in infants were accompanied by increased maternal stress level, these did not serve as a predictor of the childs social development at 12months. One-year-old girls reached a higher level of development in social and fine motor skills. No gender differences were found with regard to regulatory problems, nor any moderating effect of gender on the relation between regulatory problems and level of development. Conclusions Our results reinforce existing knowledge pertaining to the transactional association between regulatory problems in infants, maternal distress and dysfunctionality of mother-child interactions. They also provide evidence of a slight but distinct negative influence of crying and sleeping problems on childrens subsequent social development. Easily accessible support services provided by family health visitors (particularly to the so-called at-risk families) are strongly recommended to help prevent the broadening of childrens early regulatory problems into other areas of behavior. PMID:24119426

2013-01-01

279

Two-stage sampling in surveys to substantiate freedom from disease  

Microsoft Academic Search

Disease in livestock populations tends to cluster at the herd level. In order to account for thisand to overcome the problems of simple random sampling from a very large populationlarge-scale livestock surveys usually involve two-stage sampling. However, the use of two-stage sampling presents particular problems for sample-size calculation and analysis. We developed a probability formula for two-stage sampling, initially based

Angus R. Cameron; F. Chris Baldock

1998-01-01

280

Parent Involvement  

E-print Network

To be successful, a 4-H program must have parent involvement. Although 4-H leaders and Extension agents may interest young people in becoming members, they need the parents' goodwill and support to keep them interested, enthusiastic and active. Here...

Howard, Jeff W.

2005-05-10

281

Message Length Estimators, Probabilistic Sampling and Optimal Prediction  

E-print Network

applicable. Sampling involves creating a stochastic process that visits each model in the model space to perform optimal Bayesian prediction (OBP), also known as Bayesian model averaging which involves making's optimal universal search [5] approach for classes of inversion problems exists, its application

Davidson, Ian

282

Involving people.  

PubMed

A suite of resources from National Voices, the leading coalition of health and social care charities in England, aims to support commissioners and providers to access, understand and make use of the best evidence for various approaches to involving people in their own health and health care. PMID:25167121

2014-08-28

283

A Survey of Perception, Knowledge, Awareness, and attitude in Regard to Environmental Problems in a Sample of two Different Social Groups in Jakarta, Indonesia  

Microsoft Academic Search

A quantitative study was conducted in 1998 to investigate differences in perception, knowledge, awareness, and attitude with regard to environmental problems between educated and community groups and to identify human-dimension factors to improve public perception, knowledge, awareness, and attitude in relation to global environmental conservation concerns in developing countries. Educated and community groups in Jakarta were interviewed, and data obtained

Sigit Sudarmadi; Shosuke Suzuki; Tomoyuki Kawada; Herawati Netti; Soeharsono Soemantri; A. Tri Tugaswati

2001-01-01

284

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

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

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

2013-01-01

285

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

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

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

2014-01-01

286

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

PubMed Central

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

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

2013-01-01

287

Heart Problems  

NSDL National Science Digital Library

In this section we will review the major heart problems that you may encounter. Objectives -Understand the possible complications related to your heart -Identify resources that are available for Cardiology Cardiac Compromise 1. Chest pain results from ischemia 2. Ischemic heart disease involves decreased blood flow to the heart. 3. If blood flow is not restored, the tissue dies. Heart pumping with electrical activity Atherosclerosis 1. Materials build up inside blood vessels. 2. ...

Joey

2008-10-15

288

Monte Carlo Sampling Methods  

Microsoft Academic Search

In this chapter we discuss Monte Carlo sampling methods for solving large scale stochastic programming problems. We concentrate on the exterior approach where a random sample is generated outside of an optimization procedure, and then the constructed, so-called sample average approximation (SAA), problem is solved by an appropriate deterministic algorithm. We study statistical properties of the obtained SAA estimators. The

Alexander Shapiro

2003-01-01

289

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

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

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

2012-01-01

290

HIV Problem Space  

NSDL National Science Digital Library

This problem space enables investigators to explore data from a published study by Markham et al on HIV evolution within individual patients. The study involved 15 injection drug users in Baltimore, Maryland (USA) who became infected with HIV between 1989 and 1992. Patients came in at approximately six-month intervals ("visits") to have blood samples taken. From these samples, the researchers extracted and sequenced multiple copies of proviral DNA. Patients' CD4 counts were also measured at each visit to assess their level of immune function. In this problem space, you will have access to the following materials: * background information on HIV/AIDS, * the original Markham et al. reference and other primary literature, * viral sequences from each visit of each patient, * patients' CD4 counts at each visit, * phylogenetic trees of the virus sequences from each patient, * a phylogenetic tree of each patient's starting consensus viral sequence, * a published activity using this data from the book Microbes Count!, * and additional materials prepared by other users of the problem space. You can use this data to explore a number of different questions. Here are a few general questions to get you started: * Does the virus evolve the same way in different patients? * Are there any specific mutations that cause rapid immune decline? * What types of natural selection might be influencing HIV evolution? * Is HIV being transmitted between patients after initial infection?

Anton Weisstein (Truman State University;Biology); Samuel Donovan (University of Pittsburgh;)

2005-12-16

291

Distribution of chemical elements in Vaccinium myrtillus (blueberry) basic problems for representative sampling of plants for multi-element analysis in ecosystems  

Microsoft Academic Search

To get more information about establishing a representative sampling program for multi-element analysis in ecosystems, leaves and fruits ofVaccinium myrtillus were investigated for special criteria of seasonal and interherd fluctuations in elemental distribution within a forest ecosystem. Eleven chemical elements were quantitatively determined by AES\\/ICP. The interherd variances in elemental compositions of different stands ofVaccinium myrtillus (leaves) are between 12%

Bernd Markert

1989-01-01

292

The Role of Marital Discord and Parenting in Relations between Parental Problem Drinking and Child Adjustment  

ERIC Educational Resources Information Center

Background: Research suggests that children exposed to parental drinking problems are at risk for maladjustment. However, the potential impact of drinking problems in a community sample and the processes involved in the relationship between parental drinking and child outcomes have rarely been examined. Method: A community sample of 235 mothers

Keller, Peggy S.; Cummings, E. Mark; Davies, Patrick T.

2005-01-01

293

Influence of Sampling in Radiation Therapy Treatment Design  

Microsoft Academic Search

\\u000a Computer-based optimization simulations have made significant contributions to the improvement of intensity modulated radiation\\u000a therapy (IMRT) treatment planning. Large amounts of data are typically involved in radiation therapy optimization problems.\\u000a Regardless the formulation used, the problem size is always the biggest challenge to overcome. The most common strategy to\\u000a address this problem is sampling which may have a significant impact

Humberto Rocha; Joana Dias; Brigida C. Ferreira; Maria do Carmo Lopes

294

Statistical distribution sampling  

NASA Technical Reports Server (NTRS)

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

Johnson, E. S.

1975-01-01

295

The relations among cumulative risk, parenting, and behavior problems during early childhood  

Microsoft Academic Search

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 was utilized to examine longitudinal relations among these constructs, with results supporting an indirect effect

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

2008-01-01

296

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

ERIC Educational Resources Information Center

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

Beckman, Linda; Hagquist, Curt; Hellstrom, Lisa

2012-01-01

297

Sampling SIM: Sampling Distributions  

NSDL National Science Digital Library

Created by authors Beth Chance, Bob delMas and Joan Garfield, this webpage provides instructions for teaching sampling distributions using Sampling SIM software. It includes information regarding prerequisite knowledge, common misconceptions, and objectives, as well as links to an activity and a pre/post-test. This is a fairly comprehensive overview of the tools need for sampling distributions. The eight part structure employed by the authors is quite useful in assessing students knowledge gained through this activity.

Chance, Beth; Delmas, Bob; Garfield, Joan

2009-03-16

298

Chorionic villus sampling  

MedlinePLUS

Chorionic villus sampling (CVS) is a test done on some pregnant women. The test is done to screen your baby for ... 10 to 12 weeks of pregnancy. Chorionic villus sampling does not detect: Neural tube defects (these involve ...

299

Conversion Word Problems  

NSDL National Science Digital Library

This ready-to-print work sheet presents students with three problems, and in order to solve them, students must convert between smaller and larger units and use all four mathematical operations. There are a total of seven questions involving these three problems, and the conversions which students must undertake involve dollars and cents, pounds and ounces, grams and kilograms, and centimeters and meters.

Molik, Nancy

2004-01-01

300

Atmospheric Sciences: Problems and Applications.  

National Technical Information Service (NTIS)

This report attempts to summarize the types of problems that are encountered in atmospheric research and to show why such problems are indeed scientific problems of an involved and complex nature, yet, for the most part, solvable, providing sufficient att...

1977-01-01

301

Sampling and Sample Preparation  

NASA Astrophysics Data System (ADS)

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.

Morawicki, Rubn O.

302

PROBLEM SOLVING FOR ENGINEERING  

E-print Network

formulas which is not sufficient for difficult problems The Formula-Memorizing Approach: High school 1. I feel that problem-solving courses I feel that problem-solving courses involve memorizing lots is between 0 ­ 18, you favour the formula-memorizing approach If your score is between 19 ­ 36, you favour

303

Constructing Cooperative Logic Problems  

ERIC Educational Resources Information Center

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

Munakata, Mika

2005-01-01

304

Musculoskeletal involvement in sarcoidosis.  

PubMed

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 Lfgren'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-?, 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

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

2014-01-01

305

32 CFR 651.36 - Public involvement.  

...ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Assessment 651.36 Public involvement. (a) The involvement...and individuals in the development of EAs and EISs enhances collaborative issue identification and problem solving. Such...

2014-07-01

306

32 CFR 651.36 - Public involvement.  

Code of Federal Regulations, 2011 CFR

...ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Assessment 651.36 Public involvement. (a) The involvement...and individuals in the development of EAs and EISs enhances collaborative issue identification and problem solving. Such...

2011-07-01

307

32 CFR 651.36 - Public involvement.  

Code of Federal Regulations, 2013 CFR

...ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Assessment 651.36 Public involvement. (a) The involvement...and individuals in the development of EAs and EISs enhances collaborative issue identification and problem solving. Such...

2013-07-01

308

32 CFR 651.36 - Public involvement.  

Code of Federal Regulations, 2012 CFR

...ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Assessment 651.36 Public involvement. (a) The involvement...and individuals in the development of EAs and EISs enhances collaborative issue identification and problem solving. Such...

2012-07-01

309

Consensual norms regarding patient involvement  

Microsoft Academic Search

A stratified sample of 72 nurses, physicians and members of the general public met together in small tripartite dialogue groups each month for 20 months, in order to mutually identify health care behaviors that effectively involve patients in their own health care. Content analysis of 200 hours of verbatim transcripts from the dialogue sessions yielded 1245 patient involvement behaviors. These

Sandra J. Weiss

1986-01-01

310

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 ...

311

Adversarial Geospatial Abduction Problems.  

National Technical Information Service (NTIS)

Geospatial abduction problems (GAPs) involve the inference of a set of locations that best explain' a given set of locations of observations. For example, the observations might include locations where a serial killer committed murders or where insurgents...

J. P. Dickerson, P. Shakarian, V. S. Subrahmanian

2011-01-01

312

Sparse Sampling Action Values Initialized by a Compact Representation Technique  

Microsoft Academic Search

Most of the techniques proposed for problems involving mobile robots are specified in terms of optimal control of Markov decision processes (MDPs). However, the state space dimension explosion makes such tabular MDP-based solutions unfeasible. As an alternative to this, a planning technique based on sparse sampling (SSA) of simulated instances of a MDP model has been suggested. Because the execution

Celeny F. Alves; Esther L. Colombini; Carlos H. C. Ribeiro

2007-01-01

313

Stratospheric CCN sampling program  

NASA Astrophysics Data System (ADS)

Two one liter grab samples of stratospheric aerosol were returned from each of six U-2 sampling missions. Cloud condensation nuclei (CCN) spectra from each sample were obtained. Interest was centered on the effects of volcanic activity. Spurious particle generation was found to be a serious problem in container 9 LFT and a much smaller problem in container 9 RT. Initial studies of an option for improved sample containers and values were completed. A CCN spectrometer, able to operate at an internal pressure of 300 mb, was designed.

Rogers, C. F.; Hudson, J. G.

1982-01-01

314

Stoke's Law Problem Set  

NSDL National Science Digital Library

This is a problem set that involves the calculation of velocities from a Reynolds number, determination of Stoke's Law applicability, and calculation of settling velocities for a variety of grain sizes and materials. This can be used in conjunction with a lab but is itself just a problem set.

Headley, Rachel

315

What Is Problem Solving?  

ERIC Educational Resources Information Center

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

Martinez, Michael E.

1998-01-01

316

Closest-Point Problems  

Microsoft Academic Search

A number of seemingly unrelated problems involving the proximity of N points in the plane are studied, such as finding a Euclidean minimum spanning tree, the smallest circle enclosing the set, k nearest and farthest neighbors, the two closest points, and a proper straight-line triangulation. For most of the problems considered a lower bound of O(N log N) is shown.

Michael Ian Shamos; Dan Hoey

1975-01-01

317

Problem-solving variability in older spouses: how is it linked to problem-, person-, and couple-characteristics?  

PubMed

Problem-solving does not take place in isolation and often involves social others such as spouses. Using repeated daily life assessments from 98 older spouses (M age = 72 years; M marriage length = 42 years), the present study examined theoretical notions from social-contextual models of coping regarding (a) the origins of problem-solving variability and (b) associations between problem-solving and specific problem-, person-, and couple- characteristics. Multilevel models indicate that the lion's share of variability in everyday problem-solving is located at the level of the problem situation. Importantly, participants reported more proactive emotion regulation and collaborative problem-solving for social than nonsocial problems. We also found person-specific consistencies in problem-solving. That is, older spouses high in Neuroticism reported more problems across the study period as well as less instrumental problem-solving and more passive emotion regulation than older spouses low in Neuroticism. Contrary to expectations, relationship satisfaction was unrelated to problem-solving in the present sample. Results are in line with the stress and coping literature in demonstrating that everyday problem-solving is a dynamic process that has to be viewed in the broader context in which it occurs. Our findings also complement previous laboratory-based work on everyday problem-solving by underscoring the benefits of examining everyday problem-solving as it unfolds in spouses' own environment. PMID:21707180

Hoppmann, Christiane A; Blanchard-Fields, Fredda

2011-09-01

318

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

Microsoft Academic Search

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

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

2011-01-01

319

Fibonacci's Triangle: A Vehicle for Problem Solving.  

ERIC Educational Resources Information Center

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)

Ouellette, Hugh

1979-01-01

320

Finite Sampling Models  

NSDL National Science Digital Library

Created by Kyle Siegrist of the University of Alabama-Huntsville, this is an online, interactive lesson on finite sampling models. The lesson provides examples, exercises, and applets that include hypergeometric distribution, multivariate hypergeometric distribution, order statistics, the matching problem, the birthday problem, and the coupon collector problem. This is the twelfth of seventeen different lessons created by Siegrist. This site is structured much like an online textbook.

Siegrist, Kyle

2009-02-27

321

Interpreting anonymous DNA samples from mass disasters - probabilistic forensic inference using genetic markers  

Microsoft Academic Search

Motivation: The problem of identifying victims in a mass disa- ster using DNA fingerprints involves a scale of computation that requires efficient and accurate algorithms. In a typical scenario there are hundreds of samples taken from remains that must be matched to the pedigrees of the alleged victim's surviving relatives. Moreover the samples are often degraded due to heat and

Tien-ho Lin; Eugene W. Myers; Eric P. Xing

2006-01-01

322

Personality, Perceived Luck and Gambling Attitudes as Predictors of Gambling Involvement  

Microsoft Academic Search

A quantitative observational study was undertaken to examine the relationship between individual factors and level of gambling\\u000a involvement, in particular problem gambling (PG). The specific factors under study were personality, perceived luck, and attitudes\\u000a towards gambling. A sample of university students (N=185) completed a battery of questionnaires, consisting of the 16PF, Canadian Problem Gambling Index, Belief in Good Luck\\u000a Scale

Jamie Chiu; Lance Storm

2010-01-01

323

Sampling Error  

NSDL National Science Digital Library

This one page article, created by Statistics Canada, describes the meaning behind random sampling error. It points our the relationship of the random sampling error with the sample size, population size, variability of the characteristic, sampling plan, and measuring sampling error. While brief, this provides valuable information and also links users to additional resources concerning statistics.

2009-01-07

324

Aliasing-Point Sampling Theory  

NSDL National Science Digital Library

A qualitative introduction to point sampling theory and how it applies to the problem of aliasing in computer graphics and some solutions to the problem. There are only images and html pages in this section.

2007-01-20

325

A model for routing problem in quay management problem  

NASA Astrophysics Data System (ADS)

Quadratic Assignment Problem (QAP), like Vehicle Routing Problem, is one of those optimization problems that interests many researchers in the last decades. The Quay Management Problem is a specific problem which could be presented as a QAP which involves a double assignment of customers and products toward loading positions using lifting trucks. This study focuses on the routing problem while delivering the customers' demands. In this problem, lifting trucks will route around the storage sections to collect the products then deliver to the customers who are assigned to specific loading positions. The objective of minimizing the residence time for each customer is sought. This paper presents the problem and the proposed model.

Zirour, Mourad; Oughalime, Ahmed; Liong, Choong-Yeun; Ismail, Wan Rosmanira; Omar, Khairuddin

2014-06-01

326

Identifying viable "need-solution pairs": Problem solving without problem formulation  

E-print Network

Problem-solving research, and formal problem-solving practice as well, begins with the assumption that a problem has been identified or formulated for solving. The problem-solving process then involves a search for a ...

von Hippel, Eric A.

2013-11-27

327

The relations among cumulative risk, parenting, and behavior problems during early childhood  

PubMed Central

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 was utilized to examine longitudinal relations among these constructs, with results supporting an indirect effect of cumulative risk on externalizing and internalizing problems through nurturant and involved parenting. Conclusion Results highlight the importance of cumulative risk during early childhood, and particularly the effect that the level of contextual risk can have on the parenting context during this developmental period. PMID:18665880

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

2009-01-01

328

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

PubMed

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

Chung, Stephen W C; Chan, Benny T P

2010-07-16

329

Execution of Multidisciplinary Design Optimization Approaches on Common Test Problems  

NASA Technical Reports Server (NTRS)

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.

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

1997-01-01

330

National Sample Assessment Protocols  

ERIC Educational Resources Information Center

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,

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

2012-01-01

331

Sampling the Ocean Floor  

NSDL National Science Digital Library

In this lesson, students take samples from an unseen model of the ocean floor and try to accurately describe its composition. It will introduce the students to the limitations of sampling and the problem of obtaining representative samples of sea floor sediments. The lesson can also be an introduction to a study of geological oceanography or local geology. Younger children can use symbols or icons to keep track of the different sediment types as they sample, and make graphs of the total numbers of each type of sediment. Older students can compute percentages and compare the accuracy of each sample group to the actual composition of the ocean floor.

332

Problems in Remarriage  

Microsoft Academic Search

This study explored the problems in remarriages which remained intact and those which ended in divorce to determine differences in the seriousness of problems with step\\/children and whether the redivorced reported greater disagreement on key issues. The effects of gender and family structure on marital consensus were explored also. Using a matched sample of 26 remarried and redivorced individuals, the

Kay Pasley; Mark G. Koch; Marilyn Ihinger-Tallman

1994-01-01

333

Snowball Sampling  

Microsoft Academic Search

An $s$ stage $k$ name snowball sampling procedure is defined as follows: A random sample of individuals is drawn from a given finite population. (The kind of random sample will be discussed later in this section.) Each individual in the sample is asked to name $k$ different individuals in the population, where $k$ is a specified integer; for example, each

Leo A. Goodman

1961-01-01

334

Slice sampling  

Microsoft Academic Search

Markov chain sampling methods that adapt to characteristics of the distribution being sampled can be constructed using the principle that one can ample from a distribution by sampling uniformly from the region under\\u000athe plot of its density function. A Markov chain that converges to this uniform distribution can be constructed by alternating uniform sampling in the vertical direction with

Radford M. Neal

2003-01-01

335

Nonprobability Sampling  

NSDL National Science Digital Library

This site, created by author William M.K. Trochim, describes numerous methods of nonprobability sampling, including accidental, haphazard or convenience sampling and many other types of purposive methods. Some of these purposive methods he describes are: modal instance, expert, quota, heterogeneity, and snowball sampling. Overall, this is a good, albeit brief, overview of the subject of nonprobability sampling.

Trochim, William M.

2008-12-12

336

Problem drinkers and their problems  

PubMed Central

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

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

1981-01-01

337

Sampling Distribution of Sample Means  

NSDL National Science Digital Library

This applet generates a graph of the sampling distribution of sample means and displays the probabilities associated with that distribution. Users enter the mean and standard deviation of the source population and the size of the samples. The applet also calculates the standard error of the sample means.

Lowry, Richard

2009-01-08

338

Sampling Distributions  

NSDL National Science Digital Library

This applet simulates and plots the sampling distribution of various statistics (i.e. mean, standard deviation, variance). The applet allows the user to specify the population distribution, sample size, and statistic. An animated sample from the population is shown and the statistic is plotted. This can be repeated to produce the sampling distribution of the statistic. After the sampling distribution is plotted it can be compared to a normal distribution by overlaying a normal curve. These features make it useful for introducing students in a first course to the idea of a sampling distribution. The site also includes instructions and exercises.

Lane, David M.

2009-11-26

339

Sampling diffusive transition paths  

SciTech Connect

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.

F. Miller III, Thomas; Predescu, Cristian

2006-10-12

340

Parent Predictors of Changes in Child Behavior Problems  

PubMed Central

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 childrens 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

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

2013-01-01

341

Capillary sample  

MedlinePLUS

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

342

Classic Problems  

NSDL National Science Digital Library

Classic problems from the Ask Dr. Math FAQ (Frequently Asked Questions) files, including: age word problems, birthday probability, boy or girl?, camel and bananas, coin problems, doubling pennies, grazing animals, liars and truthtellers, the missing dollar, Monty Hall (three doors), three houses three utilities, the Tower of Hanoi, two trains, two trains and a fly, and working together.

Forum, Math; Math Forum; Ask Dr. Math FAQ

2002-01-01

343

Probability Sampling  

NSDL National Science Digital Library

This site, created by author William M.K. Trochim, describes in detail five different types of random sampling. Some of these types include: simple random, stratified random, systematic random, cluster random, multi-stage sampling. The author provides examples, definitions, and the procedures behind the methods. Overall, this site provides a nice overview of probability sampling.

Trochim, William M.

2008-12-30

344

Early onset and recent drug use among children of parents with alcohol problems: data from a national epidemiologic survey  

Microsoft Academic Search

There is good evidence that children of parents with alcohol problems have more drug involvement, plus related mental health and behavioral problems. In this study, we sought to estimate the degree to which these children might be more likely to initiate drug use precociously. A sample of 2888 parentchild pairs was identified within public data files of the National Household

Isidore S Obot; F. A Wagner; James C Anthony

2001-01-01

345

Random Samples  

NSDL National Science Digital Library

Created by Kyle Siegrist of the University of Alabama-Huntsville, this is an online, interactive lesson on random samples. The author provides examples, exercises, and applets concerning many different topics. Some of these include: sample mean, law of large numbers, sample variance, partial sums, central limit theorem, special properties of normal samples, order statistics, and sample covariance and correlation. Additionally, the author provides links to external resources for students wanting to engage further with the topic. This is simply one of seventeen lessons. They are all easily accessible as the author has formatted his site much like an online textbook.

Siegrist, Kyle

2009-02-18

346

Quantum rejection sampling  

E-print Network

Rejection sampling is a well-known method to sample from a target distribution, given the ability to sample from a given distribution. The method has been first formalized by von Neumann (1951) and has many applications in classical computing. We define a quantum analogue of rejection sampling: given a black box producing a coherent superposition of (possibly unknown) quantum states with some amplitudes, the problem is to prepare a coherent superposition of the same states, albeit with different target amplitudes. The main result of this paper is a tight characterization of the query complexity of this quantum state generation problem. We exhibit an algorithm, which we call quantum rejection sampling, and analyze its cost using semidefinite programming. Our proof of a matching lower bound is based on the automorphism principle which allows to symmetrize any algorithm over the automorphism group of the problem. Our main technical innovation is an extension of the automorphism principle to continuous groups that arise for quantum state generation problems where the oracle encodes unknown quantum states, instead of just classical data. Furthermore, we illustrate how quantum rejection sampling may be used as a primitive in designing quantum algorithms, by providing three different applications. We first show that it was implicitly used in the quantum algorithm for linear systems of equations by Harrow, Hassidim and Lloyd. Secondly, we show that it can be used to speed up the main step in the quantum Metropolis sampling algorithm by Temme et al.. Finally, we derive a new quantum algorithm for the hidden shift problem of an arbitrary Boolean function and relate its query complexity to "water-filling" of the Fourier spectrum.

Maris Ozols; Martin Roetteler; Jrmie Roland

2011-03-14

347

Lunar Sample Quarantine & Sample Curation  

NASA Technical Reports Server (NTRS)

The main goal of this presentation is to discuss some of the responsibility of the lunar sample quarantine project. The responsibilities are: flying the mission safely, and on schedule, protect the Earth from biohazard, and preserve scientific integrity of samples.

Allton, Judith H.

2000-01-01

348

32 CFR 651.36 - Public involvement.  

Code of Federal Regulations, 2010 CFR

...organizations, and individuals in the development of EAs and EISs enhances collaborative issue identification and problem solving. Such involvement demonstrates that the Army is committed to open decision-making and builds the necessary...

2010-07-01

349

Astronauts' menu problem.  

NASA Technical Reports Server (NTRS)

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.

Lesso, W. G.; Kenyon, E.

1972-01-01

350

Trace ratio problem revisited.  

PubMed

Dimensionality reduction is an important issue in many machine learning and pattern recognition applications, and the trace ratio (TR) problem is an optimization problem involved in many dimensionality reduction algorithms. Conventionally, the solution is approximated via generalized eigenvalue decomposition due to the difficulty of the original problem. However, prior works have indicated that it is more reasonable to solve it directly than via the conventional way. In this brief, we propose a theoretical overview of the global optimum solution to the TR problem via the equivalent trace difference problem. Eigenvalue perturbation theory is introduced to derive an efficient algorithm based on the Newton-Raphson method. Theoretical issues on the convergence and efficiency of our algorithm compared with prior literature are proposed, and are further supported by extensive empirical results. PMID:19304481

Jia, Yangqing; Nie, Feiping; Zhang, Changshui

2009-04-01

351

Genetic Algorithms for Cutting Stock Problems: With and Without Contiguity  

Microsoft Academic Search

A number of optimisation problems involve the optimal grouping of a finite set of items into a number of categories subject to one or more constraints. Such problems raise interesting issues in mapping solutions in genetic algorithms. These problems range from the knapsack problem to bin packing and cutting stock problems. This paper describes research involving cutting stock problems. Results

Robert Hinterding; Lutfar Khan

1994-01-01

352

Weekly Problems  

NSDL National Science Digital Library

This is an archive of previous problems from "Math by the Month", a regular department of Teaching Children Mathematics Journal from NCTM for K-5 teachers that features activities organized by grades K-2 and grades 3-5 and usually based on a theme associated with the particular month. Activities and problems posed are classroom-tested with an inquiry or problem-solving orientation.

2011-01-01

353

Problems on Divisibility of Binomial Coefficients  

ERIC Educational Resources Information Center

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

Osler, Thomas J.; Smoak, James

2004-01-01

354

Teaching Problem Solving to College Students  

ERIC Educational Resources Information Center

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

Malouff, John M.

2011-01-01

355

Word Problems: Simple Interest  

NSDL National Science Digital Library

This site explains to students the concept of simple interest, the four variables involved, and the formula for calculating simple interest. There is an example problem and two practice questions with hints and two more for students to take on individually. Students may check their answers when they are finished.

Taylor, Sharon

2005-01-01

356

Adversarial Geospatial Abduction Problems  

Microsoft Academic Search

Geospatial Abduction Problems (GAPs) involve the inference of a set of locations that best explain a given set of locations of observations. For example, the observations might include locations where a serial killer committed murders or where insurgents carried out Improvised Explosive Device (IED) attacks. In both these cases, we would like to infer a set of locations that explain

Paulo Shakarian; John P. Dickerson; V. S. Subrahmanian

2012-01-01

357

Selectivity Problems in Quasi-Experimental Studies  

Microsoft Academic Search

Selectivity problems can occur whenever one tries to estimate population parameters from a nonrandom sample. The sample may be nonrandom because only individuals with certain characteristics are selected into the sample (sample selection), or because individuals participate voluntarily in the sample (self-selection). Selective samples can also occur because individuals fall out of the sample for various reasons, despite an initial

Bengt Muthen; Karl G. Jreskog

1983-01-01

358

The Urban Involvement of Higher Education.  

ERIC Educational Resources Information Center

Urban problems are enormously varied and they are related to every field of teaching and research in universities. There are few areas of liberal and professional training where the interests of the university and the needs of the city do not interrelate. It was to help answer these problems that the Urban Involvement of Higher Education

Wachman, Melvin

359

Sampling Development  

ERIC Educational Resources Information Center

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

Adolph, Karen E.; Robinson, Scott R.

2011-01-01

360

Sampling Bias  

NSDL National Science Digital Library

Students will complete this activity in conjunction with an introductory statistics lesson about the importance of samples. Students will use the Oregon Reference Map and use the data to find basic statistics about samples with the help of spreadsheet software. This resource includes both a teaching guide and student lesson.

Longo, L.

2011-09-16

361

Emerging drug problems in Asia  

PubMed Central

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

Bart, Gavin

2014-01-01

362

Parking Problem  

ERIC Educational Resources Information Center

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

Foster, Colin

2012-01-01

363

Problem Solving  

NSDL National Science Digital Library

This page of videos is designed to showcase classrooms in which the NCTM Process Standards are evident. Scroll to video #48, Problem Solving, and select the "VoD" box to view this half-hour video. It includes 13 classroom excerpts from lessons that illustrate students investigating and learning mathematics through problem solving. Teachers share their approaches and observations.

Boston, Wgbh

1997-01-01

364

Effects of Family Involvement on Length of Stay and Treatment Completion Rates with Cocaine and Alcohol Abusers  

Microsoft Academic Search

Substance abuse is a problem of national concern. This study sought to replicate and further develop findings from a previous study that found cocaine abusers continued in and completed treatment less frequently than alcohol abusers, and that family involvement may influence continuation in and completion of treatment for both cocaine and alcohol abusers.A sample of 99 primary cocaine abusers and

Deni Carise

2000-01-01

365

Gubernatorial Involvement in Education.  

ERIC Educational Resources Information Center

This research on 12 States' gubernatorial involvement in State educational policy formation investigates four functional stages of that involvement--issue definition, proposal formulation, support mobilization, and decision enactment. Drawing on the Educational Governance Project information and interviews, a gubernatorial involvement index was

Hines, Edward R.

366

Sampling versus Blocking  

E-print Network

The idea of blocking in configuration space has played an important role in the development of the RG ideas. However, despite being half a century old and having had a huge intellectual impact, generic numerical methods to perform blocking for lattice models have progressed more slowly than sampling methods. Blocking may be essential to deal with near conformal situations. Typically, blocking methods have smaller statistical errors but larger systematic errors than sampling methods. This situation is evolving with recent developments based on the Tensor RG (TRG) method. We report recent results for spin and gauge lattice models obtained with this new method regarding searches for fixed points, calculations of critical exponents and resolutions of sign problems. An interesting model for comparison is the 2-dimensional O(2) model with a chemical potential which has a sign problem with conventional Monte Carlo but allows sampling with the worm algorithm and blocking with various TRG formulations. We compare the ...

Meurice, Yannick; Unmuth-Yockey, Judah; Yang, Li-Ping; Zou, Haiyuan

2014-01-01

367

Young children's ability to solve spatial problems involving a choice  

Microsoft Academic Search

When do young children become able to make an adequate choice between two alternatives based on spatial information? Children of 20, 30, and 40 months of age were either presented with two objects with different cross-sections and one aperture, or one object and two different apertures. In each trial there was one objectaperture match and the task was to find

Helena rnkloo; Claes von Hofsten

2009-01-01

368

Experiment Problems for Introductory Physics Labs  

Microsoft Academic Search

Experiment problems are an important part of Ohio State University's new laboratory program for the calculus-based introductory physics course. Students solve a problem involving laboratory apparatus, often using inexpensive toys. The problems may be poorly defined, require planned solutions before trying the experiments, and involve multiple parts and multiple concepts. Students decide what quantities to measure in order to satisfactorily

Alan van Heuvelen

1997-01-01

369

Coal Sampling  

NSDL National Science Digital Library

This USGS publication explains the use of fluxes for preparation of coal for elemental analysis. The material would be useful to supplement textbooks concerning sample preparation and may be helpful in designing an XRF laboratory experiment.

Golightly, D. W.; Simon, Frederick Otto, 1939-

2011-03-29

370

Orbit/deorbit analysis for the Mars rover sample return mission  

NASA Technical Reports Server (NTRS)

Four astrodynamic problems involved in a combined Mars rover and surface sample return mission projected for the early 1990s are explored. Two of the problems are associated with the satisfaction of the specific mission requirements at Mars, calling for the initial orbit entered into at Mars to be highly eccentric and to have a very low periapsis altitude (about 250 km). The problem of placing an areosynchronous communications satellite in orbit around Mars is then discussed. Finally, the problem of deorbiting to a specified landing site from a highly eccentric orbit is considered.

Penzo, Paul A.

1988-01-01

371

Fluidic sampling  

SciTech Connect

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.

Houck, E.D.

1992-04-20

372

The problem of pain.  

PubMed

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

Nicholson, Keith; Martelli, Michael F

2004-01-01

373

Problem Solving  

NSDL National Science Digital Library

Students are introduced to a systematic procedure for solving problems through a demonstration and then the application of the method to an everyday activity. The unit project is introduced to provide relevance to subsequent lessons.

Office Of Educational Partnerships

374

Foot Problems  

MedlinePLUS

Foot Problems Basic Facts & Information Foot pain and foot disorders are common complaints among older people. Foot ... to exercise and keep fit. Structure of the Foot Each of your feet contains 26 bones, 33 ...

375

Erection problems  

MedlinePLUS

... use recreational drugs? What is your state of mind? Are you stressed, depressed, or anxious? Are you having relationship problems? You may have a number of different tests to help find the cause, ...

376

Urination Problems  

MedlinePLUS

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

377

Shoulder Problems  

MedlinePLUS

... involving the arms, or the effects of the aging process on shoulder movement over many years, may ... Rotator cuff tendons often become inflamed from overuse, aging, or a fall on an outstretched hand or ...

378

Assessing psychopathological problems of children and adolescents from 3 to 17years in a nationwide representative sample: results of the German health interview and examination survey for children and adolescents (KiGGS)  

Microsoft Academic Search

BackgroundReliable information on the prevalence of mental health problems in children and adolescents in the general population in\\u000a Germany is scarce. With the German health and examination survey for children and adolescents (KiGGS) data is available for\\u000a the first time on psychopathological problems for the complete age range from 3 to 17years.\\u000a \\u000a \\u000a \\u000a ObjectivesTo estimate prevalence rates for several groups with

Heike Hlling; Brbel-Maria Kurth; Aribert Rothenberger; Andreas Becker; Robert Schlack

2008-01-01

379

Sampling apparatus  

DOEpatents

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.

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

1989-01-01

380

Small-sample brain mapping: sparse recovery on spatially correlated designs with randomization and clustering  

E-print Network

Small-sample brain mapping: sparse recovery on spatially correlated designs with randomization Abstract Functional neuroimaging can measure the brain's response to an external stimulus. It is used to perform brain mapping: identi- fying from these observations the brain re- gions involved. This problem

Kaski, Samuel

381

Minimax control of switching systems under sampling  

SciTech Connect

We consider a general class of systems subject to two types of uncertainty: a continuous deterministic uncertainty that affects the system dynamics, and a discrete stochastic uncertainty that leads to jumps in the system structure at random times, with the latter described by a continuous-time finite state Markov chain. When only sampled values of the system state is available to the controller, along with perfect measurements on the state of the Markov chain, we obtain a characterization of minimax controllers, which involves the solutions of two finite sets of coupled PDE`s, and a finite dimensional compensator. For the linear-quadratic case, a complete characterization is given in terms of coupled generalized Riccati equations, which also provides the solution to a particular H{infinity} optimal control problem with randomly switching system structure and sampled state measurements.

Basar, T. [Univ. of Illinois, Urbana, IL (United States)

1994-12-31

382

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...

2010-06-04

383

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...

2010-06-04

384

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...

2010-06-04

385

Transitions Into and Out of Intercollegiate Athletic Involvement and Risky Drinking  

PubMed Central

Objective: Cross-sectional data show that college athletes consume more alcohol and experience more general alcohol-related problems than those not participating in athletics. To our knowledge, the current study is the first to use a longitudinal design to examine the extent to which the course of drinking and alcohol-related problems relates to involvement in intercollegiate athletics, including transitioning into and out of athletic involvement. Method: Participants were drawn from a sample of 3,720 college students from the Intensive Multivariate Prospective Alcohol College-Transitions Study who completed a survey every semester through their fourth year. Four groups were created based on athletic involvement status at baseline (freshman year) and follow-up (senior year): nonathlete, nonathlete (no reported athletic involvement at either time point), nonathlete, athlete (nonathlete at freshman year, athlete at senior year), athlete, nonathlete (athlete at freshman year, nonathlete at senior year), and athlete, athlete (athlete at freshman year, athlete at senior year). Results: A series of repeated measures analyses were then conducted to test for developmental differences among the athlete groups involving alcohol consumption and alcohol-related problems. Although findings differed as a function of alcohol outcome and comparison among various groups with differing athletic involvement, the general pattern of results showed that individuals who were more athletically involved demonstrated sharper increases in problem drinking (i.e., heavy drinking, frequency of intoxication, alcohol-related problems) during the college years. Conclusions: These findings highlight the apparent risk associated with participation in intercollegiate athletics on college drinking. PMID:23200147

Cadigan, Jennifer M.; Littlefield, Andrew K.; Martens, Matthew P.; Sher, Kenneth J.

2013-01-01

386

STATISTICAL APPROACH TO TESTS INVOLVING PHYLOGENIES  

Microsoft Academic Search

This chapter reviews statistical testing involving phylogenies. We present both the classical framework with the use of sampling distributions involving the bootstrap and permutation tests and the Bayesian approach using posterior distributions. We give some examples of direct tests for deciding whether the data support a given tree or trees that share a particular property, comparative analyses using tests that

Susan Holmes

387

Respiratory problems in advanced cancer  

Microsoft Academic Search

Respiratory problems are an important issue in the palliative care setting, not only from a diagnostic and therapeutic point of view but also from emotion-related aspects involving both the patients and their families and also caregivers. In this paper we consider some of the most common respiratory problems, such as dyspnea, infections, hemoptysis, hiccup. A review of the literature was

Carla Ripamonti; Flavio Fusco

2002-01-01

388

Problem Solving, Scaffolding and Learning  

ERIC Educational Resources Information Center

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

Lin, Shih-Yin

2012-01-01

389

Broadcast Search in Problem Solving: Attracting Solutions From the Periphery  

Microsoft Academic Search

The purpose of this study is to explore an alternative mechanism of problem solving that focuses on broadcasting problems to diverse and peripheral problem solvers, what I call broadcast search. Broadcasting problems is a radical departure from traditional problem solving as it involves problem holders engaging in as little problem-solving as possible - instead they attempt to interest a heterogeneous

Karim R. Lakhani

2006-01-01

390

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

ERIC Educational Resources Information Center

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

Cosler, Norma, Ed.

391

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

ERIC Educational Resources Information Center

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

Cosler, Norma, Ed.

392

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

ERIC Educational Resources Information Center

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.

Cosler, Norma, Ed.

393

Games and gambling involvement among casino patrons.  

PubMed

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

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

2013-06-01

394

Word Problems: A "Meme" for Our Times.  

ERIC Educational Resources Information Center

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)

Leamnson, Robert N.

1996-01-01

395

The Problem of Managing a Strategic Reserve.  

ERIC Educational Resources Information Center

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)

Cole, David; And Others

1986-01-01

396

Session Four: Communication II, Problem-Solving,  

E-print Network

/Skills: 1. Parents will learn how to use family meetings to promote effective parent-child communication 2 practice problem solving in our group. Group Exercise Solve a problem involving a child of someone

397

Illicit drug use, alcohol use and problem drinking among infrequent and frequent road ragers  

Microsoft Academic Search

The purpose of this paper is to investigate the relationships between illicit drug and alcohol use, problem drinking, and road rage. Particular attention is devoted to the association between these behaviors and frequent involvement in road rage activities. The data are taken from the 2002 Centre for Addiction and Mental Health (CAMH) Monitor, a representative telephone survey with a sample

Jennifer E. Butters; Reginald G. Smart; Robert E. Mann; Mark Asbridge

2005-01-01

398

Using the bootstrap to estimate mean squared error and select smoothing parameter in nonparametric problems  

Microsoft Academic Search

We describe a bootstrap method for estimating mean squared error and smoothing parameter in nonparametric problems. The method involves using a resample of smaller size than the original sample. There are many applications, which are illustrated using the special cases of nonparametric density estimation, nonparametric regression, and tail parameter estimation.

Peter Hall

1990-01-01

399

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

ERIC Educational Resources Information Center

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

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

2004-01-01

400

Genes Involved in Atherosclerosis  

Microsoft Academic Search

Atherosclerosis is a multifactorial disease that involves several genes and proteins. The purpose of this article is to focus on the arterial wall and to review lipoprotein receptors, growth factors, cytokines, chemokines, matrix metalloproteinases, adhesion molecules, and apoptosis genes and their involvement in atherogenesis.

Johanna Laukkanen; Seppo Yl-Herttuala

2002-01-01

401

Mixed variational inequalities and economic equilibrium problems  

Microsoft Academic Search

We consider rather broad classes of general economic equilibrium problems and oligopolistic equilibrium problems which can be formulated as mixed variational inequality problems. Such problems involve a continuous mapping and a convex, but not necessarily differentiable function. We present existence and\\u000auniqueness results of solutions under weakened $P$ -type assumptions on the cost mapping. They enable us to establish new

I. V. Konnov; E. O. Volotskaya

2002-01-01

402

Solving the Bargaining Problem  

E-print Network

, racial minorities, governments, multinational corporations, banks, and universities. I have written textbooks for introductory sociology,social problems, criminology, family, and sport. And, I have penned essays on ethics, values, violence, crime... capitalism, interlocking ownership among 'the major 'banks, and domestic and international corporate social expenditures. Currently, I am involved in an ongoing project with David R. Simon analyzing crimes by the powerful. This research centers on crimes...

Schellenberg, James A.

1990-01-01

403

Heat Problems.  

ERIC Educational Resources Information Center

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)

Connors, G. Patrick

404

Redesigning problem solving component in General Physics course.  

NASA Astrophysics Data System (ADS)

Problem-based learning has been widely used in teaching introductory/general physics courses for a long time. The role of problem-solving sessions in the learning process is absolutely critical: they give the students an opportunity to learn how to apply both newly and previously acquired knowledge to practical situations, how to put together different strategies and portions of material, and much more. Unfortunately, the traditional format used for the problem solving sessions is not very accommodative for the goal: large class sizes and limited time often force instructors to spend most of the time solving sample problems in front of the class, which leaves the students with the role of passive observers. In this work, we will discuss how one can involve the students in the process of active learning using collaborative strategies and principles of cognitive apprenticeship.

Shakov, Jerry; McGuire, Jim

2007-04-01

405

Annealed Importance Sampling Reversible Jump MCMC algorithms  

SciTech Connect

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.

Karagiannis, Georgios; Andrieu, Christophe

2013-03-20

406

Natural History of Alcohol Dependence and Remission Events for a Native American Sample*  

PubMed Central

Objective Examining the progression of a disorder cross-culturally may help distinguish elements common to addictions from those that are differentially shaped by culture. This study sought to construct a combined sequence of both problem emergence and recovery efforts with Native Americans. Method In a cross-sectional sample, 44 adult Native Americans (61% men) who had resolved alcohol dependence completed face-to-face interviews at a research center. The Alcohol Related Behaviors Survey and the Change Effort Card-sorts along with measures of alcohol involvement and current quality of life were administered. Results This samples sequence of alcohol-related events was compared to that reported for Jellineks historical while male sample (rs = .46, p = .001), a recent Navajo sample (rs = .33, p = .024), and a recent Mission Indian sample (rs = .28, p = 24). This samples sequence of change efforts was compared to that in the Navajo sample (rs = .33, p = .182). Conclusions Despite the small sample size precluding generalizability, there was greater concordance between this intertribal sample and Jellineks while male sample than between this sample and a Mission Indian sample, indicating both cross-cultural and intracultural variation. In addition, change efforts begin during the development of alcohol problems rather than waiting until the person hits bottom, as suggested by previous research. Integrating the pathology of substance-use disorders with the process of resolving those disorders extends our understanding of the course of alcohol dependence. PMID:16847535

Venner, Kamilla L.; Feldstein, Sarah W.

2010-01-01

407

Problem Set 1 Solutions GFD1 Winter 2011 P. Rhines, A.Gray out: Friday 7 Jan 2011 back: Friday 1. Suppose we heat a small sample of dry air confined in a  

E-print Network

Jan 1. Suppose we heat a small sample of dry air confined in a cylinder. o Calculate the change column acts like the small air volumes in part one above...so the answer will be the same. But in thermal energy for a temperature rise T if the volume is held constant. Now, suppose the lid

408

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

PubMed

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

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

2014-09-01

409

Doctors' involvement in torture.  

PubMed

Doctors from both non-democratic and democratic countries are involved in torture. The majority of doctors involved in torture are doctors at risk. Doctors at risk might compromise their ethical duty towards patients for the following possible reasons: individual factors (such as career, economic or ideological reasons), threats, orders from a higher ranking officer, political initiatives, working in atrocity-producing situations or dual loyalty. In dual loyalty conflicts, factors that might compromise doctors' ethical obligations towards detainees/patients are: ideological totalitarianism, moral disengagement, victim blame, patriotism, individual factors or threats. Another important reason why doctors are involved in torture is that not all doctors are trained in addressing human rights issues of detainees. Torture survivors report that they have experienced doctors' involvement in torture and doctors themselves report that they have been involved in torture. Testimonies from both torture survivors and doctors demonstrate that the most common way doctors are involved is in the diagnosis/medical examination of torture survivors/prisoners. And it is common before, during and after torture. Both torture survivors and doctors state that doctors are involved during torture by treatment and direct participation. Doctors also falsify journals, certificates and reports. When doctors are involved in torture it has devastating consequences for both torture survivors and doctors. The consequences for the survivors can be mistrust of doctors, avoidance of seeking doctors' help and nightmares involving doctors. Mistrust and avoidance of doctors could be especially fatal to the survivor, as it could mean a survivor who is ill may not seek medical attention. When the unambiguous role of the doctor as the protector and helper of people is questioned, it affects the medical profession all over the world. PMID:19491477

Jesper, Sonntag

2008-01-01

410

Persistence in Problem Solving  

NSDL National Science Digital Library

In this 5-minute video third grade teacher Jean Saul demonstrates how she uses problem solving tasks to create a classroom climate that fosters persistence, independence, responsibility, and risk-taking. Students are asked to find three different methods for solving each problem and to record them on a Choose Three Ways graphic organizer. Through collaboration and presentation of their work to peers, students develop math language and discourse skills. A side bar provides reflection questions. Supporting materials include a transcript of the video (doc), the graphic organizer (doc), and two samples of student work (pdf).

2012-01-01

411

Alcohol Problems  

Microsoft Academic Search

\\u000a Alcohol problems can be broadly defined as negative consequences that people experience as a result of their use of alcohol.\\u000a People may drink alcohol for a number of reasons: to promote feelings of relaxation, to increase feelings of sociability,\\u000a to elevate mood, to conform to social expectations, or to reduce feelings of stress (Anonymous, 2000). Information from the\\u000a US National

David C. Hodgins; Katherine Diskin; Jonathan N. Stea

412

Problem Set 1 GFD1 Winter 2011 P. Rhines, A.Gray out: Friday 7 Jan 2011 back: Friday 14 Jan 1. Suppose we heat a small sample of dry air confined in a cylinder.  

E-print Network

. Suppose we heat a small sample of dry air confined in a cylinder. o Calculate the change in thermal energy and at T on the pressure-volume (p-v) plane, and show the curve representing the process followed by the air captured for a temperature rise T if the volume is held constant. Now, suppose the lid of the cylinder is free to rise

413

Anatomy of the Selection Problem  

Microsoft Academic Search

This article considers anew the problem of estimating a regression E(y|x) when realizations of (y, x) are sampled randomly but y is observed selectively. The central issue is the failure of the sampling process to identify E(y|x). The problem faced by the researcher is to find correct prior restrictions which, when combined with the data, identify the regression. Two kinds

Charles F. Manski

1989-01-01

414

Sports Participation and Problem Alcohol Use  

PubMed Central

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

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

2014-01-01

415

Calculation of complex equilibria involving vaporization into vacuum  

NASA Technical Reports Server (NTRS)

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.

Paule, R. C.

1974-01-01

416

Cardiac involvement in leptospirosis.  

PubMed

Leptospirosis is a neglected global disease with significant morbidity and mortality. Cardiac complications such as chest pain, arrhythmias, pulmonary oedema and refractory shock have been reported in patients with severe disease. However, the frequency and extent of cardiac involvement in leptospirosis, are under-reported and poorly understood. Multiple factors may contribute to clinical manifestations that suggest cardiac involvement, causing diagnostic confusion. A variety of electrocardiographic changes occur in leptospirosis, with atrial fibrillation, atrioventricular conduction blocks and non-specific ventricular repolarization abnormalities being the most common. Electrolyte abnormalities are likely to contribute to electrocardiographic changes; direct effects on Na(+)-K(+)-Cl(-) transporters in the renal tubules have been postulated. Echocardiographic evidence of myocardial dysfunction has not been adequately demonstrated. The diagnostic value of cardiac biomarkers is unknown. Histopathological changes in the myocardium have been clearly shown, with myocardial inflammation and vasculitis present in postmortem studies. Nonetheless, the pathophysiology of cardiac involvement in leptospirosis is poorly understood. Cardiac involvement, demonstrated electrocardiographically or clinically, tends to predict poor outcome. No specific therapies are available to prevent or treat cardiac involvement in leptospirosis; current management is based on correction of deranged homeostasis and supportive therapy. Evidence suggests that direct myocardial damage occurs in patients with severe leptospirosis, and further studies are recommended to elucidate its pathophysiology, clinical features and contribution to overall prognosis, and to identify appropriate diagnostic investigations and specific therapies. PMID:22818758

Navinan, Mitrakrishnan Rayno; Rajapakse, Senaka

2012-09-01

417

No Problem with Problem Solving  

ERIC Educational Resources Information Center

Having used the DfES "Problem Solving" pack in a variety of school and centre-based applications, the author taught some of the lessons to classes of children and also observed lessons from the pack being taught to classes from Y1 to Y6. The lessons are part of a series of materials from the Primary National Strategy designed to help all staff

Kurta, Jon

2006-01-01

418

Problems without Numbers--At First  

ERIC Educational Resources Information Center

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

Hewitt, Paul G.

2006-01-01

419

Medical problems of musicians.  

PubMed

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

Lockwood, A H

1989-01-26

420

Involving Divorced Parents.  

ERIC Educational Resources Information Center

In divorced families, the noncustodial parent is usually as important to the child as the residential parent. Schools should avoid actions that cause parental conflict, place one parent in a sole decision-making role, or deny a parent's access to information or involvement. School responsibilities governing routine correspondence, cyclical and

Tarriff, Harold M.; Levine, Valerie

1993-01-01

421

Getting Parents Involved.  

ERIC Educational Resources Information Center

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

Butts, Vickie; Finch, Patty A.

1985-01-01

422

Kidney involvement in systemic sclerosis.  

PubMed

Kidney involvement in systemic sclerosis (SSc) is primarily manifested by scleroderma renal crisis (SRC). Formerly, it was the most severe complication in scleroderma and was the most frequent cause of death in these patients. More than 30years ago, with the development of angiotensin converting enzyme (ACE) inhibitors, SRC became a very treatable complication of scleroderma. Although there are still many patients who do not survive and have poor outcomes, early diagnosis of renal crisis and prompt therapeutic intervention can achieve excellent outcomes. Renal abnormalities independent of renal crisis have been noted, but can usually be attributed to other problems. Further understanding of the pathogenesis of renal disease in scleroderma may lead to additional improvement in the therapy of renal crisis and perhaps the disease in general. This chapter reviews the pathogenesis, clinical setting, and therapy of this serious complication of SSc. PMID:25174767

Steen, Virginia D

2014-10-01

423

Principles for Sampling Airborne Radioactivity from Stacks  

SciTech Connect

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.

Glissmeyer, John A.

2010-10-18

424

Conformational sampling via a self-regulating effective energy surface.  

PubMed

The difficulty of efficiently sampling the phase space of complex systems with rough energy surfaces is well known. Typical solutions to the problem involve accelerating the crossing of barriers, but such methods often have the secondary problem that the low-energy states of interest are inadequately sampled, unless the parameters of the search algorithm are modified as the system evolves. A method is presented to improve the sampling with particular emphasis on the low-energy conformations, which make the most important contributions to the thermodynamics of the system. The algorithm proposed here samples the details of the minima, while easily surmounting barriers. This is achieved by introducing a self-regulating sampling variable which depends on the current state of the system. Two replicas of the system are introduced and the sampling variable is treated as a particle coupled to the physical system. The method is illustrated with a simple model system and is applied to the realistic example of barrier crossing in a protein-ligand complex. PMID:16689598

Bitetti-Putzer, Ryan; Dinner, Aaron R; Yang, Wei; Karplus, Martin

2006-05-01

425

Conformational sampling via a self-regulating effective energy surface  

NASA Astrophysics Data System (ADS)

The difficulty of efficiently sampling the phase space of complex systems with rough energy surfaces is well known. Typical solutions to the problem involve accelerating the crossing of barriers, but such methods often have the secondary problem that the low-energy states of interest are inadequately sampled, unless the parameters of the search algorithm are modified as the system evolves. A method is presented to improve the sampling with particular emphasis on the low-energy conformations, which make the most important contributions to the thermodynamics of the system. The algorithm proposed here samples the details of the minima, while easily surmounting barriers. This is achieved by introducing a self-regulating sampling variable which depends on the current state of the system. Two replicas of the system are introduced and the sampling variable is treated as a particle coupled to the physical system. The method is illustrated with a simple model system and is applied to the realistic example of barrier crossing in a protein-ligand complex.

Bitetti-Putzer, Ryan; Dinner, Aaron R.; Yang, Wei; Karplus, Martin

2006-05-01

426

Solving Satisfiability and Implication Problems in Database Systems  

E-print Network

conjunctive inequalities are important and widely encountered database problems that need to be efficientlySolving Satisfiability and Implication Problems in Database Systems SHA GUO, WEI SUN, and MARK A. WEISS Florida International University Satisfiability, implication, and equivalence problems involving

Weiss, Mark Allen

427

Mental Health and Substance Abuse Services to Parents of Children Involved with Child Welfare: A Study of Racial and Ethnic Differences for American Indian Parents  

Microsoft Academic Search

American Indian (AI) parents of children involved with child welfare were compared to White, Black and Hispanic parents on\\u000a mental health and substance abuse problems and access to treatment. Data came from the National Study of Child and Adolescent\\u000a Well-Being, a longitudinal study of a nationally representative sample of children aged 014years involved with child welfare.\\u000a Weighted statistics provided population

Anne M. Libby; Heather D. Orton; Richard P. Barth; Mary Bruce Webb; Barbara J. Burns; Patricia A. Wood; Paul Spicer

2007-01-01

428

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

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

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

2007-01-01

429

Measuring the prevalence of sector-specific problem gambling: a study of casino patrons.  

PubMed

This study is the first attempt to measure the prevalence of problem gambling attributable to a specific sector of the gambling industry. One thousand, one hundred and five casino patrons in 40 casinos in the UK were interviewed, face-to-face. Respondents were screened for problem gambling using a multiple response version of DSM-IV (DSM-IV-MR). The study found support for Eadington's (1988) hypothesis, that UK casinos could be largely sustained by regular players, among whom the prevalence of problem gambling is high. The study also found support for the hypothesis that, to the extent different gambling sectors are patronised by demographically different client groups, so the problem gamblers associated with them will reflect these client groups. The problem gamblers among the regular casino patrons were demographically distinct from the problem gamblers in the sample who showed a preference for other gambling forms. Other key findings support those found in other jurisdictions. Sector-specific prevalence studies may be the next step forward in epidemiological research on problem gambling. They have the major advantage of netting significantly more problem gamblers from much smaller samples than similar studies in the general population. They also have the potential to reveal the proportion of problem gamblers attributable to each sector, along with their demographic characteristics. Such information would result in more specific information being available for regulators seeking to minimise the social impact of problem gambling and those involved in the development of prevention and treatment strategies. PMID:14634320

Fisher, S

2000-01-01

430

7 CFR 800.81 - Sample requirements; general.  

...GENERAL REGULATIONS Inspection Methods and Procedures 800.81 ...new sample involves a change in method of sampling. (b) Representative sample...appropriate, from the time of sampling or receipt until the...

2014-01-01

431

Religious involvement and the forgiving personality.  

PubMed

The relationship between religious involvement and forgiveness was assessed in three samples of Western Europeans living in a social environment dominated by the Catholic tradition. The samples comprised nonbelievers/nonattendees, believers/nonattendees, believers/regular attendees, and religious people. Age and religious involvement were shown to affect the willingness to forgive in an interactive way: The effect of religious involvement was stronger for the elderly group. We also found that what made the difference in the willingness to forgive was mainly the social commitment to religion (attendance in church and the taking of vows), not mere personal beliefs. In addition, age and religious involvement were found to affect blockage towards forgiveness in an additive way. PMID:12597235

Mullet, Etienne; Barros, Jos; Frongia, Loredana; Usa, Veronica; Neto, Flix; Shafighi, Sheila Rivire

2003-02-01

432

Test of association between GABRA2 (SNP rs279871) and adolescent conduct/alcohol use disorders utilizing a sample of clinic referred youth with serious substance and conduct problems, controls and available first degree relatives  

PubMed Central

Recent findings have linked the GABRA2 gene with antisocial personality disorder and alcohol dependence (AD) in adults and conduct disorder (CD), but not AD symptoms, in children and adolescents. We sought to replicate previous findings and test for an association between a single nucleotide polymorphism (SNP) in the GABRA2 gene (rs279871) and CD among adolescents. Methods Adolescent patients (n=371), 13-18 years old, were recruited from a university substance abuse treatment program. Patient siblings (n=245), parents of patients (n=355), adolescent controls (n=185), siblings of controls (n=163) and parents of controls (n=263) were included in these analyses (total sample n=1,582). Case-control (using only Caucasian and Hispanic probands) and family-based association tests were completed to test for association between rs279871 and several a priori CD and AD phenotypes. Results For case-control association tests, rs279871 was significantly associated with CD (p=0.02) but not AD phenotypes; the result did not survive strict correction for multiple testing. All family-based association tests were non-significant (CD p=0.48; CD symptom count age corrected within sex p=0.91; AD p=0.84; alcohol use disorder p=0.52). Conclusions Consistent with previous findings, the results do not support the association between GABRA2 SNP rs279871 and AD in adolescents. Our results also do not support an association between rs279871 and CD; the study limitations are reviewed. PMID:19783384

Sakai, Joseph T.; Stallings, Michael C.; Crowley, Thomas J.; Gelhorn, Heather L.; McQueen, Matthew B.; Ehringer, Marissa A.

2010-01-01

433

Cosmological Constant Problems and Renormalization Group  

E-print Network

The Cosmological Constant Problem emerges when Quantum Field Theory is applied to the gravitational theory, due to the enormous magnitude of the induced energy of the vacuum. The unique known solution of this problem involves an extremely precise fine-tuning of the vacuum counterpart. We review a few of the existing approaches to this problem based on the account of the quantum (loop) effects and pay special attention to the ones involving the renormalization group.

Ilya L. Shapiro; Joan Sola

2006-11-08

434

Whippo Problem Space  

NSDL National Science Digital Library

The investigations listed here are not intended to be an inclusive list of possibilities but instead represent a first pass at some different ways that beginning researchers might fruitfully engage with this problem space. Some of these investigations could be supported with data found in this problem space while others would involve seeking additional resources. Our hope in listing these ideas is that both faculty and students will be stimulated to engage in research, curriculum development, or other types of scholarship that can be shared with this community. Our overarching goal is to support biology teaching and learning that more closely reflects the ways that biologists work with data to develop arguments and test hypotheses.

Sam Donovan (University of Pittsburgh;)

2004-06-26

435

Sparse grid collocation schemes for stochastic natural convection problems  

SciTech Connect

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.

Ganapathysubramanian, Baskar [Materials Process Design and Control Laboratory, Sibley School of Mechanical and Aerospace Engineering, 188 Frank H.T. Rhodes Hall, Cornell University, Ithaca, NY 14853-3801 (United States); Zabaras, Nicholas [Materials Process Design and Control Laboratory, Sibley School of Mechanical and Aerospace Engineering, 188 Frank H.T. Rhodes Hall, Cornell University, Ithaca, NY 14853-3801 (United States)]. E-mail: zabaras@cornell.edu

2007-07-01

436

Neurological involvement in legionellosis  

PubMed Central

A study of the clinical, electrophysiological and biochemical features of 16 patients with legionellosis has been performed. Evidence of central and peripheral nervous system involvement has been found in the majority of patients. This is characterised by confusion out of keeping with the degree of toxic or metabolic upset, signs of anterior midline cerebellar dysfunction, grossly elevated creatinine kinase of skeletal muscle origin, and a subclinical peripheral neuropathy. PMID:7119829

Weir, AI; Bone, I; Kennedy, DH

1982-01-01

437

Locker Problem  

NSDL National Science Digital Library

A classroom activity (also called 1000 Lockers) aligned to the NCTM and California Standards, to be explored through the use of manipulatives and a ClarisWorks spreadsheet. Students then look for patterns and write the answer algebraically. The problem: imagine you are at a school that still has student lockers. There are 1000 lockers, all shut and unlocked, and 1000 students. Suppose the first student goes along the row and opens every other locker. The second student then goes along and shuts every other locker beginning with number 2. The third student changes the state of every third locker beginning with number 3. (If the locker is open the student shuts it, and if the locker is closed the student opens it.) The fourth student changes the state of every fourth locker beginning with number 4. Imagine that this continues until the thousand students have followed the pattern with the thousand lockers. At the end, which lockers will be open and which will be closed? Why? A a href= /alejandre/frisbie/locker.html teacher lesson plan/a is provided.

Forum, Math; Alejandre, Suzanne

2001-01-01

438

The Yo-Yo Problem  

NSDL National Science Digital Library

In this math lesson, learners explore linear patterns, write a pattern in symbolic form, and solve linear equations using algebra tiles, symbolic manipulation, and a graphing calculator. The lesson begins with the presentation of the yo-yo problem. Then learners complete a hands-on activity involving a design created with pennies. Algebra tiles are introduced next as learners practice solving linear equations. Finally, learners return to solving the yo-yo problem.

Pbs

2012-01-01

439

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

Microsoft Academic Search

The purpose of this study was to examine archival data from an outpatient clinic serving children with autism spectrum disorders\\u000a to investigate the occurrence of problem behavior functions in this sample. Results indicated that social reinforcement (e.g.,\\u000a attention from others) was involved in maintaining problem behavior for the majority of cases, suggesting that these children\\u000a lacked socially appropriate responses to

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

2009-01-01

440

The Relationship Between Post-Traumatic Stress Symptoms and Substance Use Among Adolescents Involved with Child Welfare: Implications for Emerging Adulthood  

Microsoft Academic Search

The purpose of the present study was to examine the role of posttraumatic stress symptoms (PTSS) in predicting substance use\\u000a and substance-related problems in a sample of older youth and emerging adults involved with child welfare. The sample was\\u000a drawn from the Maltreatment and Adolescent Pathways (MAP) longitudinal study (Wekerle et al. 2009). Participants were 253 youth and emerging adults

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

441

Patterns of Organized Activity Participation in Urban, Early AdolescentsAssociations With Academic Achievement, Problem Behaviors, and Perceived Adult Support  

Microsoft Academic Search

This study examines patterns of organized activity and their concurrent association with academic achievement, problem behavior, and perceived adult support in a sample of urban, early adolescent, middle school students (mean age = 13.01; N = 2,495). Cluster analyses yielded six activity profiles: an uninvolved group ( n = 775, 31.1%), a multiply involved group (n = 247, 9.9%), a

Aaron Metzger; Hugh F. Crean; Emma L. Forbes-Jones

2009-01-01

442

Improved separation techniques for the characterization of radioactive waste samples  

SciTech Connect

Analysts have routinely used organic solvent extractions and precipitation techniques to remove matrix constituents which interfere with the characterization of radioactive waste samples. Problems with these traditional techniques involve the production of organic waste and time consuming steps. Extraction chromatography using recently developed resins manufactured by Eichrom Industries provides accuracy comparable to traditional techniques while reducing waste and time. Three types of Eichrom resins were evaluated on samples from radioactive waste tanks at the Department of Energy`s (DOE) Oak Ridge National Laboratory (ORNL) for the analysis of the inorganic EPA target analyte elements, radioactive strontium, and radioactive technetium. Results show that extraction chromatography may be successfully applied to the characterization of DOE radioactive waste samples similar to those at ORNL, providing high efficiency, reduced waste production, and safety benefits.

Meeks, A.M.; Keller, J.M.; Giaquinto, J.M.; Ross, T.

1994-12-31

443

Sample Sizes for Usability Studies: Additional Considerations  

Microsoft Academic Search

ABSTRACT Recently, Virzi (1992) presented data that support three claims regarding sample sizes for usability studies. The claims were (1) observing four or five participants will allow a usability practitioner to discover 80% of a product's usability problems, (2) observing additional participants will reveal fewer and fewer new usability problems, and (3) more severe usability problems are easier to detect

James R. Lewis

444

Acceptance sampling using judgmental and randomly selected samples  

SciTech Connect

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.

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

2010-09-01

445

Endocannabinoid involvement in endometriosis.  

PubMed

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. Herein, using a rat model, we found that CB1 cannabinoid receptors are expressed on both the somata and fibers of both the sensory and sympathetic neurons that innervate endometriosis's abnormal growths. We further found that CB1 receptor agonists decrease, whereas CB1 receptor antagonists increase, endometriosis-associated hyperalgesia. Together these findings suggest that the endocannabinoid system contributes to mechanisms underlying both the peripheral innervation of the abnormal growths and the pain associated with endometriosis, thereby providing a novel approach for the development of badly-needed new treatments. PMID:20833475

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

2010-12-01

446

There are solutions to problems.  

PubMed

In these times of health care reform and change there are an increasing number of problems in the health care workplace that health care managers must face. Solving problems successfully is important for survival of the manager and for smooth delivery of care. The challenge of solving problems can be faced by a systematic response that includes having faith in oneself, clearly defining the problem, not jumping to conclusions, considering the overall goal, getting staff involved as soon as possible, reviewing all possible options for obtaining results, developing a plan of action, selecting a strategic time to take action, conveying appropriate urgency about the problem, having faith in colleagues and staff, implementing the plan, using resources available, and evaluating the outcome as well as the process. PMID:10747464

Davidhizar, R E; Bowen, M

1999-09-01

447

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

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

448

Generativity and Social Involvement among African Americans and White Adults  

Microsoft Academic Search

The study examined the relation between generativity and social involvement in a sample of 253 community adults, approximately half African American and half White, between the ages of 34 and 65 years. For the sample as a whole, individual differences in generativity were positively asociated with social support from family and friends, involvement in religious activities, and political participation, and

Holly M. Hart; Dan P. McAdams; Barton J. Hirsch; Jack J. Bauer

2001-01-01

449

Stages in Adolescent Involvement in Drug Use  

Microsoft Academic Search

Two longitudinal surveys based on random samples of high school students in New York State indicate four stages in the sequence of involvement with drugs: beer or wine, or both; cigarettes or hard liquor; marihuana; and other illicit drugs. The legal drugs are necessary intermediates between nonuse and marihuana. Whereas 27 percent of high school students who smoke and drink

Denise Kandel

1975-01-01

450

Screening for problem drinking  

Microsoft Academic Search

OBJECTIVE: To compare self-administered versions of three questionnaires for detecting heavy and problem drinking: the CAGE, the Alcohol\\u000a Use Disorders Identification Test (AUDIT), and an augmented version of the CAGE.\\u000a \\u000a \\u000a DESIGN: Cross-sectional surveys.\\u000a \\u000a \\u000a \\u000a \\u000a SETTING: Three Department of Veterans Affairs general medical clinics.\\u000a \\u000a \\u000a \\u000a \\u000a PATIENTS: Random sample of consenting male outpatients who consumed at least 5 drinks over the past year (drinkers).

Katharine A. Bradley; Kristen R. Bush; Mary B. McDonell; Timothy Malone; Stephan D. Fihn

1998-01-01

451

Rock Samples and Geochemistry Analyses  

NSDL National Science Digital Library

In this lab set students use field work to collect a granite sample which will be prepared for whole-rock analyses through ICP-AES, AAS, and XRF methodologies, as well as mineral concentrations and thin sections for microprobe. The bulk of these exercices involve sample and data manipulation and also include some open-ended questions as comparisons between mineral and whole-rock composition, different kind of data presentation in geochemistry, and limitations and applicability of distinct analytical methodologies.

Lourdes, Maria R.

452

Optimizing patient involvement in quality improvement  

PubMed Central

IntroductionPatient and public involvement in healthcare planning, service development and health-related research has received significant attention. However, evidence about the role of patient involvement in quality improvement work is more limited. We aimed to characterize patient involvement in three improvement projects and to identify strengths and weaknesses of contrasting approaches. MethodsThree case study quality improvement projects were purposively sampled from a broader programme. We used an ethnographic approach involving 126 in-depth interviews, 12?weeks of non-participant observations and documentary analysis. Data analysis was based on the constant comparative method. ResultsThe three projects differed in the ways they involved patients in their quality improvement work, including their rationales for including patients. We characterized three very different models of patient involvement, which were each influenced by project context. Patients played distinctive roles across the three projects, acting in some cases as intermediaries between the wider patient community and clinicians, and sometimes undertaking persuasive work to convince clinicians of the need for change. We identified specific strategies that can be used to help ensure that patient involvement works most effectively and that the enthusiasm of patients to make a difference is not dissipated. ConclusionPatient involvement in quality improvement work needs careful management to realize its full potential. PMID:23374430

Armstrong, Natalie; Herbert, Georgia; Aveling, Emma-Louise; Dixon-Woods, Mary; Martin, Graham

2013-01-01

453

Two problems in finite elasticity  

Microsoft Academic Search

Some materials encountered in nature and used in engineering exhibit mechanical effects which cannot be adequately explained by classical linear elastic theories. For example, rubber is an elastic material that undergoes large elastic deformations, and therefore renders a non-linear mechanical behavior. An analytical investigation dealing with the problem of static deformation of such materials therefore involves highly non-linear equations leading

Himanshuki Nilmini Padukka Withana

2009-01-01

454

Ocular involvement in scleroderma.  

PubMed

Thirty-eight patients with scleroderma (progressive systemic sclerosis) without renal failure were subjected to detailed clinical ophthalmic assessment. Abnormalities were frequent. However, many of these, including lens opacities, vitreous frosting, and arteriosclerotic changes, were considered to be age-related, and there were various incidental changes. Posterior subcapsular lens opacities in one patient were probably corticosteroid-induced. Changes related to scleroderma included eyelid abnormalities (stiffness or tightness in 11, telangiectasia in 8), deficient tear secretion (14 cases), and conjunctival abnormalities (injection 19 cases, vascular sludging 27 cases). Iris light reflux (6 cases) was possibly related to scleroderma. The changes related to scleroderma occurred in the 3 types classified according to the extent of skin involvement. PMID:526467

West, R H; Barnett, A J

1979-12-01

455

The worldwide "wildfire" problem.  

PubMed

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

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

2013-03-01

456

Young adults talk about their problems.  

PubMed

This study aims to explore how young adults in psychotherapy and young adults in general describe their problems and how their problem formulations change over time. Two matched samples from longitudinal prospective studies were compared using thematic analysis. Semi-structured, in-depth interviews were conducted at baseline, 1.5 years after termination of psychotherapy (N=12) in the clinical sample and 3 years after baseline in the non clinical sample (N=12). Inductive thematic analysis revealed six themes: problems associated with oneself, family, intimate relationships, sense of belonging, occupation, and social roles. The psychotherapy sample was characterized by problems with oneself closely related to other problematic areas, at both pre-treatment and at follow-up 1.5 years after termination, while problematic sense of belonging was a general theme only prior to psychotherapy. However, they were less troubled by their problems after psychotherapy. Problems with oneself decreased considerably in the non-clinical sample, while problems with intimate relationships were twice as frequent at follow-up. In the psychotherapy sample, the initial experience of being passively trapped within their problems was transformed into an experience of being an active agent in their own life. However, considerable differences between the psychotherapy sample and non-clinical sample still persisted at follow-up. PMID:21323672

Jacobsson, Gunnel; Tysklind, Fredrik; Werbart, Andrzej

2011-06-01

457

Experiment Problems for Introductory Physics Labs*  

NASA Astrophysics Data System (ADS)

Experiment problems are an important part of Ohio State University's new laboratory program for the calculus-based introductory physics course. Students solve a problem involving laboratory apparatus, often using inexpensive toys. The problems may be poorly defined, require planned solutions before trying the experiments, and involve multiple parts and multiple concepts. Students decide what quantities to measure in order to satisfactorily complete the experiment and must justify approximations. Several examples will be provided including a multipart Hot Wheels experiment that is analyzed by students during the last mechanics lab. The use of the problems in a lecture setting will also be demonstrated.

van Heuvelen, Alan

1997-04-01

458

Improved sample size determination for attributes and variables sampling  

SciTech Connect

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.

Stirpe, D.; Picard, R.R.

1985-01-01

459

Convergence of Sequential Sampling Policies for Bayesian Information Collection Problems  

E-print Network

Test the policy with monte carlo simulation on a collection of test cases. 3 If it performs badly, go with monte carlo simulation on a collection of test cases. 3 If the policy performs badly, go back to step 1, deciding which types of measurement to make as we go. e.g., We decide sequentially where to measure

Keinan, Alon

460

Solving Multistage Asset Investment Problems by the Sample ...  

E-print Network

Consider now the power utility function U(z) ? z?/?, with ? ? 1, ? = 0 (in that case U(z) .... conditions, the SAA estimators are consistent in the sense that they converge with probability one to ..... want to find a feasible decision, uj, to node j

2005-06-27

461

Marital discord and child behavior problems in a nonclinic sample  

Microsoft Academic Search

Mothers' evaluations of their marital relationship and of their children's behavior at home and teachers' ratings of the children's behavior in school were obtained using well-established measures. While an association was found between ratings of marital discord and children's problematic behavior, the relation was a fairly weak one. The present findings are discussed in comparison to the results of other

Robert E. Emery; K. Daniel O'Leary

1984-01-01

462

Using Biweights in the Two-Sample Problem.  

National Technical Information Service (NTIS)

It is proposed to replace the usual Student's-t statistic which tests for equality of means of two distributions and to construct a confidence interval for the difference by a biweight-'t' statistic. The biweight-'t' is a ratio of the difference of the bi...

K. Kafadar

1979-01-01

463

Sequential Requests and the Problem of Message Sampling.  

ERIC Educational Resources Information Center

S. Jackson and S. Jacobs's criticism of "single message" designs in communication research served as a framework for a study that examined the differences between various sequential request paradigms. The study sought to answer the following questions: (1) What were the most naturalistic request sequences assured to replicate "foot-in-the-door"

Cantrill, James Gerard

464

New approach to the fault location problem using synchronized sampling  

E-print Network

Error (%): RL Line Model Based Algorithm, f, = 12KHz 47 III Fault Location Error (%): RL Line Model Based Algorithm, f, = 8KHz 48 IV Fault Location Error (%): RL Line Model Based Algorithm, f, = 6KHz 49 V Fault Location Error (%): Traveling Wave... Based Algorithm, f, = 24KHz VI Fault Location Error (%): Traveling Wave Based Algorithm, f, = 12KHz 53 VII Fault Location Error (%): Traveling Wave Based Algorithm, f, = 8KHz 54 VIII Fault Location Error (%): Traveling Wave Based Algorithm, f, = 6...

Mrkic, Jasna

2012-06-07

465

E#ciently Determine the Starting Sample Size for Progressive Sampling  

E-print Network

E#ciently Determine the Starting Sample Size for Progressive Sampling Baohua Gu # Bing Liu, how to set the starting sample size for PS is still an open problem. We show that an improper starting sample size can still make PS expensive in computation due to running the learning algorithm on a large

Liu, Bing

466

Skeletal muscle tuberculosis simultaneously involving multiple sites.  

PubMed

Tuberculosis (TB) continues to be a public health problem in both developing and industrialized countries. TB of the skeletal muscle is very rare. We present a case of the simultaneous involvement of skeletal muscles in multiple sites in an 11-year-old immune-competent female patient. All physicians should have adequate knowledge of TB and awareness of its atypical presentations to ensure the proper management of such patients. PMID:22561909

Neogi, Devdatta S; Bandekar, Shivanand M; Chawla, Lokesh

2013-03-01

467

Economics of Carbon Sequestration Projects Involving Smallholders  

Microsoft Academic Search

\\u000a Afforestation and reforestation projects have the potential to help mitigate global warming by acting as sinks for CO2. However, participation in carbon-sink projects may be constrained by high costs. This problem may be particularly severe\\u000a for projects involving smallholders in developing countries. Of particular concern are the transaction costs incurred in developing\\u000a projects and measuring, certifying, and selling the carbon-sequestration

Oscar Cacho

468

Applying Employee Involvement in Schools.  

ERIC Educational Resources Information Center

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

Mohrman, Susan Albers; And Others

1992-01-01

469

ADJOINT BASED SAMPLING METHODS FOR ELECTROMAGNETIC SCATTERING  

E-print Network

ADJOINT BASED SAMPLING METHODS FOR ELECTROMAGNETIC SCATTERING H. EGGER, M. HANKE, C. SCHNEIDER, J of sampling methods, based on solutions of certain adjoint problems. This adjoint ap- proach does not require and all dipole direc- tions simultaneously; thus several limitations of standard sampling methods

Hanke-Bourgeois, Martin

470

On near-uniform URL sampling  

Microsoft Academic Search

We consider the problem of sampling URLs uniformly at random from the Web. A tool for sampling URLs uniformly can be used to estimate various properties of Web pages, such as the fraction of pages in various Internet domains or written in various languages. Moreover, uniform URL sampling can be used to determine the sizes of various search engines relative

Monika Rauch Henzinger; Allan Heydon; Michael Mitzenmacher; Marc Najork

2000-01-01

471

AEROSOL SAMPLING INLETS AND INHALABLE PARTICLES  

EPA Science Inventory

The problem of sampling aerosols from the ambient atmosphere has been considered from a theoretical point of view. Following a review of the various samplers and inlets used in ambient sampling, the factors contributing to high sampling efficiency for large particles are discusse...

472

[Endocrine involvement in immunotherapy].  

PubMed

Thyroid dysfunction and abnormalities in corticosteroid regulation were observed after clinical use of cytokines (IL2, IFN alpha), molecules with immunostimulating properties. Interleukin 2 administration induces hypothyroidism often associated with anti-thyroglobulin and anti-thyroid microsomal antibody. All these features recall Hashimoto's thyroiditis. Frequency of thyroid dysfunction during immunotherapy varies according to authors between 20 and 40 percent of all patients treated. A correlation between thyroid dysfunction and response to IL2 therapy was reported. Hypothyroidism and hyperthyroidism with development of anti-TSH receptor antibody are observed after IFN alpha administration. An auto-immune aetiology of these thyroid side effects was suggested because fine needle aspirates of the thyroid of these patients, when available, revealed a mixed cellular infiltrate with lymphocytes and histiocytes and immunocytochemical staining showed strong HLA-DR expression of all thyrocytes. Involvement of lymphokine activated killer (LAK) or direct effect of cytokines on thyroid are also possible. After intravenous injection of IL2, a marked increase in ACTH levels occurred, peaking at 4 hour with a comparable peak in cortisol level at 5 hour. Expression of IL2-Receptor in pituitary cells suggests a direct action of IL2 on anterior pituitary. Nevertheless, indirect action of IL2 via induction of other cytokines or possible secretion of ACTH by activated lymphocytes, cannot be ruled out. Testosterone serum levels decreased significantly after IL2 or IFN alpha administration. It is noteworthy that these endocrine effects induced by cytokines may modulate the clinical efficacy of these substances underlying the bi-directional communication between the immune and endocrine system. PMID:7755342

Tartour, E; Schlumberger, M; Dorval, T; Baudin, E; Fridman, W H

1995-01-01

473

Health literacy, numeracy, and other characteristics associated with hospitalized patients' preferences for involvement in decision making.  

PubMed

Little research has examined the association of health literacy and numeracy with patients' preferred involvement in the problem-solving and decision-making process in the hospital. Using a sample of 1,249 patients hospitalized with cardiovascular disease from the Vanderbilt Inpatient Cohort Study (VICS), we assessed patients' preferred level of involvement using responses to two scenarios of differing symptom severity from the Problem-Solving Decision-Making Scale. Using multivariable modeling, we determined the relationship of health literacy, subjective numeracy, and other patient characteristics with preferences for involvement in decisions, and how this differed by scenario. The authors found that patients with higher levels of health literacy desired more participation in the problem-solving and decision-making process, as did patients with higher subjective numeracy skills, greater educational attainment, female gender, less perceived social support, or greater health care system distrust (p<.05 for each predictor in multivariable models). Patients also preferred to participate more in the decision-making process when the hypothetical symptom they were experiencing was less severe (i.e., they deferred more to their physician when the hypothetical symptom was more severe). These findings underscore the role that patient characteristics, especially health literacy and numeracy, play in decisional preferences among hospitalized patients. PMID:25315582

Goggins, Kathryn M; Wallston, Kenneth A; Nwosu, Samuel; Schildcrout, Jonathan S; Castel, Liana; Kripalani, Sunil; For The Vanderbilt Inpatient Cohort Study Vics

2014-10-01

474

Religious involvement and mortality: A meta-analytic review  

Microsoft Academic Search

A meta-analysis of data (mm 42 independent samples examining the association of a measure of religious involvement and all-cause mortality is reported. Religious involvement was significantly associated with lower mortality (odds ratio = 1.29; 95% confidence interval: 1.20-1.39), indicating that people high in religious involvement were more likely to be alive at follow-up than people lower in religious involve- ment.

Michael E. McCullough; William T. Hoyt; David B. Larson; Harold G. Koenig; Carl Thoresen

2000-01-01

475

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 ...

476

Sample preparation in alkaline media  

NASA Astrophysics Data System (ADS)

The use of tetramethylammonium hydroxide, tertiary amines and strongly alkaline reagents for sample treatment involving extraction and digestion procedures is discussed in this review. The preparation of slurries is also discussed. Based on literature data, alkaline media offer a good alternative for sample preparation involving an appreciable group of analytes in different types of samples. These reagents are also successfully employed in tailored speciation procedures wherein there is a critical dependence on maintenance of chemical forms. The effects of these reagents on measurements performed using spectroanalytical techniques are discussed. Several undesirable effects on transport and atomization processes necessitate use of the method of standard additions to obtain accurate results. It is also evident that alkaline media can improve the performance of techniques such as inductively coupled plasma mass spectrometry and accessories, such as autosamplers coupled to graphite furnace atomic absorption spectrometers.

Nbrega, Joaquim A.; Santos, Mirian C.; de Sousa, Rafael A.; Cadore, Solange; Barnes, Ramon M.; Tatro, Mark

2006-05-01

477

Stochastic Transportation-Inventory Network Design Problem  

E-print Network

In this paper, we study the stochastic transportation-inventory network design problem involving one supplier and multiple retailers. Each retailer faces some uncertain demand. Due to this uncertainty, some amount of safety ...

Shu, Jia

478

A systematic approach to representative sampling in the environment  

SciTech Connect

In environmental sampling, samples are taken for the purpose of solving a problem in a target population. The problem may not be correctly solved if bias is present in the samples, in the measurement of the samples, and/or in the use of the sample data to make conclusions about the population. This paper discusses a systematic approach which considers all these potential sources of bias when attempting to obtain a representative set of samples for making inference about the population.

Chai, E.Y. [Shell Development Co., Houston, TX (United States)

1996-12-31

479

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

PubMed

For decades there have been two young driver concepts: the 'young driver problem' where the driver cohort represents a key problem for road safety; and the 'problem young driver' where a sub-sample of drivers represents the greatest road safety problem. Given difficulties associated with identifying and then modifying the behaviour of the latter group, broad countermeasures such as graduated driver licensing (GDL) have generally been relied upon to address the young driver problem. GDL evaluations reveal general road safety benefits for young drivers, yet they continue to be overrepresented in fatality and injury statistics. Therefore it is timely for researchers to revisit the 'problem young driver' concept to assess its potential countermeasure implications. This is particularly relevant within the context of broader countermeasures that have been designed to address the 'young driver problem' Personal characteristics, behaviours and attitudes of 378 Queensland novice drivers aged 17-25 years were explored during their pre-, Learner and Provisional 1 (intermediate) licence as part of a larger longitudinal project. Self-reported risky driving was measured by the Behaviour of Young Novice Drivers Scale (BYNDS), and five subscale scores were used to cluster the drivers into three groups (high risk n=49, medium risk n=163, low risk n=166). High risk 'problem young drivers' were characterised by greater self-reported pre-Licence driving, unsupervised Learner driving, and speeding, driving errors, risky driving exposure, crash involvement, and offence detection during the Provisional period. Medium risk drivers were also characterised by more risky road use than the low risk group. Interestingly problem young drivers appear to have some insight into their high-risk driving, since they report significantly greater intentions to bend road rules in future driving. The results suggest that tailored intervention efforts may need to target problem young drivers within the context of broad countermeasures such as GDL which address the young driver problem in general. Experiences such as crash-involvement could be used to identify these drivers as a preintervention screening measure. PMID:23792613

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

2013-10-01

480

Physics Suite Peer Instruction Problems: Dynamics  

NSDL National Science Digital Library

This website contains a series of peer instruction problems on dynamics, designed to be solved in a classroom setting. The problems are presented with a qualitative (usually multiple choice) question that is carefully constructed to engage student difficulties with fundamental concepts. Students consider the problem individually and contribute their answers using personal response systems (clickers). Students then confer with their cooperative groups and vote again on the correct response. Topics covered include force, acceleration, normal force, friction, tension, and motion in two dimensions. This problem set is part of the Physics Suite collection, containing sample problems, peer instruction problems, and alternative homework sets.

Redish, Edward F.

2008-08-11

481

Physics Suite Peer Instruction Problems: Rotational Motion  

NSDL National Science Digital Library

This website contains a series of peer instruction problems on rotational motion, designed to be solved in a classroom setting. The problems are presented with a qualitative que