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Sample records for models boys identify

  1. Using Discrete Trial Training to Identify Specific Learning Impairments in Boys with Fragile X Syndrome

    Science.gov (United States)

    Hall, Scott S.; Hustyi, Kristin M.; Hammond, Jennifer L.; Hirt, Melissa; Reiss, Allan L.

    2014-01-01

    We examined whether "discrete trial training" (DTT) could be used to identify learning impairments in mathematical reasoning in boys with fragile X syndrome (FXS). Boys with FXS, aged 10-23 years, and age and IQ-matched controls, were trained to match fractions to pie-charts and pie-charts to decimals either on a computer or with a…

  2. Identifiability in stochastic models

    CERN Document Server

    1992-01-01

    The problem of identifiability is basic to all statistical methods and data analysis, occurring in such diverse areas as Reliability Theory, Survival Analysis, and Econometrics, where stochastic modeling is widely used. Mathematics dealing with identifiability per se is closely related to the so-called branch of ""characterization problems"" in Probability Theory. This book brings together relevant material on identifiability as it occurs in these diverse fields.

  3. Modeling Growth in Boys' Aggressive Behavior across Elementary School: Links to Later Criminal Involvement, Conduct Disorder, and Antisocial Personality Disorder

    Science.gov (United States)

    Schaeffer, Cindy M.; Petras, Hanno; Ialongo, Nicholas; Poduska, Jeanne; Kellam, Sheppard

    2003-01-01

    The present study used general growth mixture modeling to identify pathways of antisocial behavior development within an epidemiological sample of urban, primarily African American boys. Teacher-rated aggression, measured longitudinally from 1st to 7th grade, was used to define growth trajectories. Three high-risk trajectories (chronic high,…

  4. Testicular Biopsy for Fertility Preservation in Prepubertal Boys with Cancer: Identifying Preferences for Procedure and Reactions to Disclosure Practices.

    Science.gov (United States)

    Gupta, Abha A; Donen, Rachel M; Sung, Lillian; Boydell, Katherine M; Lo, Kirk C; Stephens, Derek; Pritchard, Sheila; Portwine, Carol; Maloney, Anne Marie; Lorenzo, Armando J

    2016-07-01

    Fertility preservation options are limited in prepubertal boys with cancer. Worldwide there has been growing interest in testicular tissue cryopreservation as a promising experimental strategy to address future infertility. We measured and compared parent, male cancer survivor and provider willingness to accept the risk of testicular biopsy among prepubertal boys with cancer, and identified reactions to disclosure practices. We conducted a multicenter study that included 153 parents of prepubertal boys with cancer, 77 male survivors of childhood cancer and 30 oncology providers. The threshold technique was used to measure subject relative willingness to accept risk of testicular biopsy under 4 different aspects of care, ie chance of infertility, complications from biopsy, development of technology to use tissue and tissue storage cost. A total of 47 in-depth interviews were conducted to identify reactions to disclosure practices. A total of 52 survivors (67%), 22 providers (73%) and 110 parents (72%) selected to have testicular biopsy (vs no biopsy). Median minimum infertility risk to make biopsy worthwhile varied from 25% to 30% among the 3 respondent groups. Interviews revealed that some providers would not offer biopsy in cases of greater perceived risk than benefit, that parents preferred having information regardless of risk of infertility and that nondisclosure elicited adverse feelings from some parents. Parents, survivors and providers were willing to accept risk of prepubertal testicular biopsy. Parental/survivor desire for information and provider decision not to disclose suggest that barriers to information delivery need to be addressed. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  5. Birth Order and Susceptibility to Peer Modeling Influences in Young Boys

    Science.gov (United States)

    Finley, Gordon E.; Cheyne, James A.

    1976-01-01

    Susceptibility to peer modeling influences as a function of birth order was studied by examining the data of 390 boys from kindergarten through third grade who previously had participated in moral transgression experiments. (MS)

  6. Sparse Linear Identifiable Multivariate Modeling

    DEFF Research Database (Denmark)

    Henao, Ricardo; Winther, Ole

    2011-01-01

    and bench-marked on artificial and real biological data sets. SLIM is closest in spirit to LiNGAM (Shimizu et al., 2006), but differs substantially in inference, Bayesian network structure learning and model comparison. Experimentally, SLIM performs equally well or better than LiNGAM with comparable......In this paper we consider sparse and identifiable linear latent variable (factor) and linear Bayesian network models for parsimonious analysis of multivariate data. We propose a computationally efficient method for joint parameter and model inference, and model comparison. It consists of a fully...

  7. Boys Will Be Boys.

    Science.gov (United States)

    Broude, Gwen J.

    1999-01-01

    Many psychologists assert that boys are in dire straits in U.S. society, but in fact, there is no evidence of an emotional or behavioral epidemic for either sex. If there is any truth to the claim that boys are in trouble, it results from practices that foster aggression. It is a mistake to regard either gender as "fragile." (SLD)

  8. Modeling Dexterity Development in 2nd-4th-grade Boys by Means of Active Games

    Directory of Open Access Journals (Sweden)

    C. Марченко

    2017-06-01

    Full Text Available The objective is to optimize the mode of using game for dexterity development in the 2nd-4th-grade boys. Materials & methods: to conduct the experiment, there were eight test groups (n=48 formed in each class. The total number of such test groups was 24. The research relied on the following methods: theoretical analysis and collation of scientific and methodological literature; pedagogical testing; methods of mathematical experiment planning (complete factorial experiment 23; modeling method. Results: the research has determined that to develop dexterity, the 2nd-4th-grade boys need to participate in up to five games. The number of repetitions for the 2nd-3rd-graders is two, and for the 4th-graders – three, with 30–40-second rest intervals. The 2nd-4th-grade boys showed effective development during 40 classes, and the 3rd-grade boys – during 20 classes. After that, we recommend to use other means. The game duration varies from one to two minutes. Conclusions: the analysis of the scientific and methodological literature has revealed that the level of motor readiness, dexterity being one of its main components, largely determines the state of children’s physical and mental health. The research has found that the natural development of coordination abilities in boys aged between 7 and 10 is 22.5–80.0% (56.2% on average. Game actions play a particular role in dexterity development in junior schoolers. The 23 complete factorial experiment made it possible to study the multi-factorial structure of game load for the 2nd-4th-graders; to specify the relations between factors for their use during dexterity development in the 2nd-4th-grade boys in physical education classes. They can serve as an objective tool for the educational process optimization. The given regression equations are models that can be used to determine the optimal game means ratio in the academic process of the 2nd-4th-graders.

  9. Individual differences in boys' and girls' timing and tempo of puberty: modeling development with nonlinear growth models.

    Science.gov (United States)

    Marceau, Kristine; Ram, Nilam; Houts, Renate M; Grimm, Kevin J; Susman, Elizabeth J

    2011-09-01

    Pubertal development is a nonlinear process progressing from prepubescent beginnings through biological, physical, and psychological changes to full sexual maturity. To tether theoretical concepts of puberty with sophisticated longitudinal, analytical models capable of articulating pubertal development more accurately, we used nonlinear mixed-effects models to describe both the timing and tempo of pubertal development in the sample of 364 White boys and 373 White girls measured across 6 years as part of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. Individual differences in timing and tempo were extracted with models of logistic growth. Differential relations emerged for how boys' and girls' timing and tempo of development were related to physical characteristics (body mass index, height, and weight) and psychological outcomes (internalizing problems, externalizing problems, and risky sexual behavior). Timing and tempo are associated in boys but not girls. Pubertal timing and tempo are particularly important for predicting psychological outcomes in girls but only sparsely related to boys' psychological outcomes. Results highlight the importance of considering the nonlinear nature of puberty and expand the repertoire of possibilities for examining important aspects of how and when pubertal processes contribute to development.

  10. Identifiability of PBPK Models with Applications to ...

    Science.gov (United States)

    Any statistical model should be identifiable in order for estimates and tests using it to be meaningful. We consider statistical analysis of physiologically-based pharmacokinetic (PBPK) models in which parameters cannot be estimated precisely from available data, and discuss different types of identifiability that occur in PBPK models and give reasons why they occur. We particularly focus on how the mathematical structure of a PBPK model and lack of appropriate data can lead to statistical models in which it is impossible to estimate at least some parameters precisely. Methods are reviewed which can determine whether a purely linear PBPK model is globally identifiable. We propose a theorem which determines when identifiability at a set of finite and specific values of the mathematical PBPK model (global discrete identifiability) implies identifiability of the statistical model. However, we are unable to establish conditions that imply global discrete identifiability, and conclude that the only safe approach to analysis of PBPK models involves Bayesian analysis with truncated priors. Finally, computational issues regarding posterior simulations of PBPK models are discussed. The methodology is very general and can be applied to numerous PBPK models which can be expressed as linear time-invariant systems. A real data set of a PBPK model for exposure to dimethyl arsinic acid (DMA(V)) is presented to illustrate the proposed methodology. We consider statistical analy

  11. Structural Identifiability of Dynamic Systems Biology Models.

    Science.gov (United States)

    Villaverde, Alejandro F; Barreiro, Antonio; Papachristodoulou, Antonis

    2016-10-01

    A powerful way of gaining insight into biological systems is by creating a nonlinear differential equation model, which usually contains many unknown parameters. Such a model is called structurally identifiable if it is possible to determine the values of its parameters from measurements of the model outputs. Structural identifiability is a prerequisite for parameter estimation, and should be assessed before exploiting a model. However, this analysis is seldom performed due to the high computational cost involved in the necessary symbolic calculations, which quickly becomes prohibitive as the problem size increases. In this paper we show how to analyse the structural identifiability of a very general class of nonlinear models by extending methods originally developed for studying observability. We present results about models whose identifiability had not been previously determined, report unidentifiabilities that had not been found before, and show how to modify those unidentifiable models to make them identifiable. This method helps prevent problems caused by lack of identifiability analysis, which can compromise the success of tasks such as experiment design, parameter estimation, and model-based optimization. The procedure is called STRIKE-GOLDD (STRuctural Identifiability taKen as Extended-Generalized Observability with Lie Derivatives and Decomposition), and it is implemented in a MATLAB toolbox which is available as open source software. The broad applicability of this approach facilitates the analysis of the increasingly complex models used in systems biology and other areas.

  12. Coherence method of identifying signal noise model

    International Nuclear Information System (INIS)

    Vavrin, J.

    1981-01-01

    The noise analysis method is discussed in identifying perturbance models and their parameters by a stochastic analysis of the noise model of variables measured on a reactor. The analysis of correlations is made in the frequency region using coherence analysis methods. In identifying an actual specific perturbance, its model should be determined and recognized in a compound model of the perturbance system using the results of observation. The determination of the optimum estimate of the perturbance system model is based on estimates of related spectral densities which are determined from the spectral density matrix of the measured variables. Partial and multiple coherence, partial transfers, the power spectral densities of the input and output variables of the noise model are determined from the related spectral densities. The possibilities of applying the coherence identification methods were tested on a simple case of a simulated stochastic system. Good agreement was found of the initial analytic frequency filters and the transfers identified. (B.S.)

  13. Exploiting intrinsic fluctuations to identify model parameters.

    Science.gov (United States)

    Zimmer, Christoph; Sahle, Sven; Pahle, Jürgen

    2015-04-01

    Parameterisation of kinetic models plays a central role in computational systems biology. Besides the lack of experimental data of high enough quality, some of the biggest challenges here are identification issues. Model parameters can be structurally non-identifiable because of functional relationships. Noise in measured data is usually considered to be a nuisance for parameter estimation. However, it turns out that intrinsic fluctuations in particle numbers can make parameters identifiable that were previously non-identifiable. The authors present a method to identify model parameters that are structurally non-identifiable in a deterministic framework. The method takes time course recordings of biochemical systems in steady state or transient state as input. Often a functional relationship between parameters presents itself by a one-dimensional manifold in parameter space containing parameter sets of optimal goodness. Although the system's behaviour cannot be distinguished on this manifold in a deterministic framework it might be distinguishable in a stochastic modelling framework. Their method exploits this by using an objective function that includes a measure for fluctuations in particle numbers. They show on three example models, immigration-death, gene expression and Epo-EpoReceptor interaction, that this resolves the non-identifiability even in the case of measurement noise with known amplitude. The method is applied to partially observed recordings of biochemical systems with measurement noise. It is simple to implement and it is usually very fast to compute. This optimisation can be realised in a classical or Bayesian fashion.

  14. Ebola Virus Infection Modelling and Identifiability Problems

    Directory of Open Access Journals (Sweden)

    Van-Kinh eNguyen

    2015-04-01

    Full Text Available The recent outbreaks of Ebola virus (EBOV infections have underlined the impact of the virus as a major threat for human health. Due to the high biosafety classification of EBOV (level 4, basic research is very limited. Therefore, the development of new avenues of thinking to advance quantitative comprehension of the virus and its interaction with the host cells is urgently neededto tackle this lethal disease. Mathematical modelling of the EBOV dynamics can be instrumental to interpret Ebola infection kinetics on quantitative grounds. To the best of our knowledge, a mathematical modelling approach to unravel the interaction between EBOV and the host cells isstill missing. In this paper, a mathematical model based on differential equations is used to represent the basic interactions between EBOV and wild-type Vero cells in vitro. Parameter sets that represent infectivity of pathogens are estimated for EBOV infection and compared with influenza virus infection kinetics. The average infecting time of wild-type Vero cells in EBOV is slower than in influenza infection. Simulation results suggest that the slow infecting time of EBOV could be compensated by its efficient replication. This study reveals several identifiability problems and what kind of experiments are necessary to advance the quantification of EBOV infection. A first mathematical approach of EBOV dynamics and the estimation of standard parametersin viral infections kinetics is the key contribution of this work, paving the way for future modelling work on EBOV infection.

  15. Modeling of Teaching 5th-7th-Grade Boys Physical Exercises

    Directory of Open Access Journals (Sweden)

    Т. Г. Абдулхалікова

    2017-09-01

    Full Text Available The research objective is to determine the effectiveness of orthogonal variants of teaching 5th-7th graders physical exercises. Materials and methods. The participants in the research were boys of the 5th grade (n = 32, 6th grade (n = 40, 7th grade (n = 52. To achieve the tasks set, the research used the following methods: analysis of scientific and methodological literature; pedagogical testing, pedagogical observation, timing of educational tasks; pedagogical experiment, medical and biological research methods; methods of mathematical statistics, methods of mathematical experiment planning. In order to achieve the objective set, the research has studied the effect of different variants of the educational process structure, namely: the number of repetitions (х1 and rest intervals (х2 when learning the technique of performing physical exercises. The research has conducted a complete factor experiment of type 22. According to the experiment plan, the 5th-7th graders were divided into training groups. In total, there were 12 experimental groups organized. Research results. The analysis of the regression equations shows that the teaching of physical exercises to the 5th-7th-grade boys is mostly influenced by rest intervals between repetitions (х2. The number of repetitions (х1 has somewhat less influence. The interaction of these factors is insignificant when teaching physical exercises and becomes much more influential only when teaching a switch leg pull-over exercise (х1х2. Conclusions. To increase the effectiveness of teaching 5th-7th graders physical exercises, it is necessary to shorten rest intervals between repetition to 60 s and to reduce the number of repetitions to six. When teaching boys the switch leg pull-over exercise, rest intervals should be increased to 120 s and the number of repetitions — to twelve.

  16. Exploring a model linking social physique anxiety, drive for muscularity, drive for thinness and self-esteem among adolescent boys and girls.

    Science.gov (United States)

    Brunet, Jennifer; Sabiston, Catherine M; Dorsch, Kim D; McCreary, Donald R

    2010-03-01

    This study examined gender differences on body image measures, and tested a model where self-esteem influences social physique anxiety (SPA), which in turn influences drive for muscularity and drive for thinness in a sample of adolescents (N=329; 58% boys). Multi-group invariance analyses indicated that the measurement and structural models were partially invariant for boys and girls, allowing for gender comparisons. Results indicated that boys reported significantly lower drive for thinness and SPA, and higher drive for muscularity and self-esteem compared to girls. The measurement and structural models were an adequate fit for the total sample. Findings supported the proposed sequence in which self-esteem significantly influenced SPA, and SPA significantly influenced the drives for muscularity and thinness. Interventions aimed at decreasing SPA, by promoting self-esteem, may be helpful in decreasing adolescent boys' and girls' drive for muscularity and thinness. Copyright 2009 Elsevier Ltd. All rights reserved.

  17. Identifying optimal models to represent biochemical systems.

    Directory of Open Access Journals (Sweden)

    Mochamad Apri

    Full Text Available Biochemical systems involving a high number of components with intricate interactions often lead to complex models containing a large number of parameters. Although a large model could describe in detail the mechanisms that underlie the system, its very large size may hinder us in understanding the key elements of the system. Also in terms of parameter identification, large models are often problematic. Therefore, a reduced model may be preferred to represent the system. Yet, in order to efficaciously replace the large model, the reduced model should have the same ability as the large model to produce reliable predictions for a broad set of testable experimental conditions. We present a novel method to extract an "optimal" reduced model from a large model to represent biochemical systems by combining a reduction method and a model discrimination method. The former assures that the reduced model contains only those components that are important to produce the dynamics observed in given experiments, whereas the latter ensures that the reduced model gives a good prediction for any feasible experimental conditions that are relevant to answer questions at hand. These two techniques are applied iteratively. The method reveals the biological core of a model mathematically, indicating the processes that are likely to be responsible for certain behavior. We demonstrate the algorithm on two realistic model examples. We show that in both cases the core is substantially smaller than the full model.

  18. IDENTIFIABILITY VERSUS HETEROGENEITY IN GROUNDWATER MODELING SYSTEMS

    Directory of Open Access Journals (Sweden)

    A M BENALI

    2003-06-01

    Full Text Available Review of history matching of reservoirs parameters in groundwater flow raises the problem of identifiability of aquifer systems. Lack of identifiability means that there exists parameters to which the heads are insensitive. From the guidelines of the study of the homogeneous case, we inspect the identifiability of the distributed transmissivity field of heterogeneous groundwater aquifers. These are derived from multiple realizations of a random function Y = log T  whose probability distribution function is normal. We follow the identifiability of the autocorrelated block transmissivities through the measure of the sensitivity of the local derivatives DTh = (∂hi  ∕ ∂Tj computed for each sample of a population N (0; σY, αY. Results obtained from an analysis of Monte Carlo type suggest that the more a system is heterogeneous, the less it is identifiable.

  19. A Study of Boys' Reading.

    Science.gov (United States)

    Telford, Lesley

    1999-01-01

    Examined how reading attitudes of Year 6 boys in British primary schools were influenced by gender issues, peers, and peer group culture. Found that confidence and experience shown in private reading was at odds with boys' public attitudes in discussion with peers. Suggests that siblings and adults might provide more positive role models for…

  20. Using Persuasion Models to Identify Givers.

    Science.gov (United States)

    Ferguson, Mary Ann; And Others

    1986-01-01

    Assesses the feasibility of and suggests using W. J. McGuire's information processing theory and cognitive response analysis theory in research studies to identify "givers"--those who are likely to contribute money and resources to charities or volunteer to aid philanthropic organizations. (SRT)

  1. Identifying misbehaving models using baseline climate variance

    Science.gov (United States)

    Schultz, Colin

    2011-06-01

    The majority of projections made using general circulation models (GCMs) are conducted to help tease out the effects on a region, or on the climate system as a whole, of changing climate dynamics. Sun et al., however, used model runs from 20 different coupled atmosphere-ocean GCMs to try to understand a different aspect of climate projections: how bias correction, model selection, and other statistical techniques might affect the estimated outcomes. As a case study, the authors focused on predicting the potential change in precipitation for the Murray-Darling Basin (MDB), a 1-million- square- kilometer area in southeastern Australia that suffered a recent decade of drought that left many wondering about the potential impacts of climate change on this important agricultural region. The authors first compared the precipitation predictions made by the models with 107 years of observations, and they then made bias corrections to adjust the model projections to have the same statistical properties as the observations. They found that while the spread of the projected values was reduced, the average precipitation projection for the end of the 21st century barely changed. Further, the authors determined that interannual variations in precipitation for the MDB could be explained by random chance, where the precipitation in a given year was independent of that in previous years.

  2. Identifying nonproportional covariates in the Cox model

    Czech Academy of Sciences Publication Activity Database

    Kraus, David

    2008-01-01

    Roč. 37, č. 4 (2008), s. 617-625 ISSN 0361-0926 R&D Projects: GA AV ČR(CZ) IAA101120604; GA MŠk(CZ) 1M06047; GA ČR(CZ) GD201/05/H007 Institutional research plan: CEZ:AV0Z10750506 Keywords : Cox model * goodness of fit * proportional hazards assumption * time-varying coefficients Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.324, year: 2008

  3. A novel deletion in the thyrotropin Beta-subunit gene identified by array comparative genomic hybridization analysis causes central congenital hypothyroidism in a boy originating from Turkey.

    Science.gov (United States)

    Hermanns, Pia; Couch, Robert; Leonard, Norma; Klotz, Cherise; Pohlenz, Joachim

    2014-01-01

    Isolated central congenital hypothyroidism (ICCH) is rare but important. Most ICCH patients are diagnosed later, which results in severe growth failure and intellectual disability. We describe a boy with ICCH due to a large homozygous TSHβ gene deletion. A 51-day-old male Turkish infant, whose parents were first cousins, was admitted for evaluation of prolonged jaundice. His clinical appearance was compatible with hypothyroidism. Venous thyrotropin (TSH) was undetectably low, with a subsequent low free T4 and a low free T3, suggestive of central hypothyroidism. Using different PCR protocols, we could not amplify both coding exons of the boy's TSHβ gene, which suggested a deletion. An array comparative genomic hybridization (aCGH) using specific probes around the TSHβ gene locus showed him to be homozygous for a 6-kb deletion spanning all exons and parts of the 5' untranslated region of the gene. Infants who are clinically suspected of having hypothyroidism should be evaluated thoroughly, even if their TSH-based screening result is normal. In cases with ICCH and undetectably low TSH serum concentrations, a TSHβ gene deletion should be considered; aCGH should be performed when gene deletions are suspected. In such cases, PCR-based sequencing techniques give negative results.

  4. Physical Activity Levels and Motivational Responses of Boys and Girls: A Comparison of Direct Instruction and Tactical Games Models of Games Teaching in Physical Education

    Science.gov (United States)

    Smith, Lindsey; Harvey, Stephen; Savory, Louise; Fairclough, Stuart; Kozub, Stephen; Kerr, Catherine

    2015-01-01

    The purpose of this study was to independently determine the levels of moderate-to-vigorous physical activity (MVPA) and self-determined motivation of both boys and girls as they participated in prolonged units of invasion games (i.e. 6-12 lessons) through two pedagogical models: direct instruction and the tactical games model (TGM). It was…

  5. Make your Boy surface

    OpenAIRE

    Ogasa, Eiji

    2013-01-01

    This is an introductory article on the Boy surface. Boy found that RP2 can be immersed into R3 and published it 1901. (The image of) the immersion is called the Boy surface after Boy's discovery. We have created a way to construct the Boy surface by using a pair of scissors, a piece of paper, and a strip of scotch tape. In this article we introduce the way.

  6. Identifiability Results for Several Classes of Linear Compartment Models.

    Science.gov (United States)

    Meshkat, Nicolette; Sullivant, Seth; Eisenberg, Marisa

    2015-08-01

    Identifiability concerns finding which unknown parameters of a model can be estimated, uniquely or otherwise, from given input-output data. If some subset of the parameters of a model cannot be determined given input-output data, then we say the model is unidentifiable. In this work, we study linear compartment models, which are a class of biological models commonly used in pharmacokinetics, physiology, and ecology. In past work, we used commutative algebra and graph theory to identify a class of linear compartment models that we call identifiable cycle models, which are unidentifiable but have the simplest possible identifiable functions (so-called monomial cycles). Here we show how to modify identifiable cycle models by adding inputs, adding outputs, or removing leaks, in such a way that we obtain an identifiable model. We also prove a constructive result on how to combine identifiable models, each corresponding to strongly connected graphs, into a larger identifiable model. We apply these theoretical results to several real-world biological models from physiology, cell biology, and ecology.

  7. Boys' Music? School Context and Middle-School Boys' Musical Choices

    Science.gov (United States)

    Bennetts, Kathleen Scott

    2013-01-01

    This article focusses primarily on the findings relating to the musical participation of boys in one Melbourne school. As part of a project that investigated boys' attitudes and participation at fifty-one schools, several contextual features were identified that set "Balton Boys" High School' apart from other participating schools,…

  8. A Note on the Identifiability of Generalized Linear Mixed Models

    DEFF Research Database (Denmark)

    Labouriau, Rodrigo

    2014-01-01

    I present here a simple proof that, under general regularity conditions, the standard parametrization of generalized linear mixed model is identifiable. The proof is based on the assumptions of generalized linear mixed models on the first and second order moments and some general mild regularity...... conditions, and, therefore, is extensible to quasi-likelihood based generalized linear models. In particular, binomial and Poisson mixed models with dispersion parameter are identifiable when equipped with the standard parametrization...

  9. Understanding boys': thinking through boys, masculinity and suicide.

    Science.gov (United States)

    Mac An Ghaill, Mairtin; Haywood, Chris

    2012-02-01

    In the UK, the media are reporting increasing rates of childhood suicide, while highlighting that increasing numbers of pre-adolescent boys (in relation to girls) are diagnosed as mentally ill. In response, academic, professional and political commentators are explaining this as a consequence of gender. One way of doing this has been to apply adult defined understandings of men and masculinities to the attitudes and behaviours of pre-adolescent boys. As a consequence, explanations of these trends point to either 'too much' masculinity, such as an inability to express feelings and seek help, or 'not enough' masculinity that results in isolation and rejection from significant others, such as peer groups. Using a discourse analysis of semi-structured interviews with 28 children aged 9-13 (12 male, 16 females) and 12 school staff at a school in North East England, this article questions the viability of using normative models of masculinity as an explanatory tool for explaining boys' behaviours and suggests that researchers in the field of gender and suicide consider how boys' genders may be constituted differently. We develop this argument in three ways. First, it is argued that studies that use masculinity tend to reduce the formation of gender to the articulation of power across and between men and other men and women. Second, we argue that approaches to understanding boys' behaviours are simplistically grafting masculinity as a conceptual frame onto boy's attitudes and behaviours. In response, we suggest that it is important to re-think how we gender younger boys. The final section focuses specifically on the ways that boys engage in friendships. The significance of this section is that we need to question how notions of communication, integration and isolation, key features of suicide behaviours, are framed through the local production of friendships. Copyright © 2010 Elsevier Ltd. All rights reserved.

  10. Predictors of smoking among the secondary high school boy students based on the health belief model

    Directory of Open Access Journals (Sweden)

    Samira Mohammadi

    2017-01-01

    Full Text Available Background: Smoking is one of the most important risk factors for health and also health problems, such as heart diseases, especially for young people. This study aimed to investigate the effect of factors related to smoking among the secondary high school students in the city of Marivan (Kurdistan-Iran, in 2015, based on the constructs of health belief model (HBM. Methods: This cross-sectional study was conducted in 470 secondary high school students in Marivan in 2015. The samples were selected by random cluster sampling. A question with four sections was used to collect data (demographic questions, knowledge section, attitude section, and questions related to e constructs of HBM. Results: According to the results, the correlation of smoking was stronger with attitude (r = 0.269 and odds ratio = 0.89 but weaker with perceived barriers (r = 0.101. There was not a significant correlation between smoking behavior and knowledge of the harms of smoking (r = −0.005. Moreover, Cues to action was effective predictor of smoking behavior (r = 0.259. Conclusions: The findings of this study show that the prevalence of smoking in the studied sample is somewhat lower than other regions of Iran, but it should be noted that if no interventions are done to prevent smoking in this age group. The findings of the study also showed that the structure of attitudes, self-efficacy, and Cues to action are the strongest predictors of smoking among students. Albeit, attitude was strongest predictor of smoking that shows the prevalence of smoking can be reduced by focusing in this part. Considering the mean age of participants (16/2 ± 0.25 years, that shows the riskiest period for smoking is 16 years and authorities can make change in policies of cigarette selling only for over 18 years.

  11. Delayed puberty in boys

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007695.htm Delayed puberty in boys To use the sharing features on this page, please enable JavaScript. Delayed puberty in boys is when puberty does not begin ...

  12. Supporting Boys as Readers

    Science.gov (United States)

    Serafini, Frank

    2013-01-01

    The challenges associated with boys and reading are focused on such factors as society's lack of focus on literacy skills, parents failings to inspire reading in boys, and internal motivational factors rather than looking at the environments created for reading in and out of school. In this column, several ideas for helping boys develop a…

  13. Structural identifiability analysis of a cardiovascular system model.

    Science.gov (United States)

    Pironet, Antoine; Dauby, Pierre C; Chase, J Geoffrey; Docherty, Paul D; Revie, James A; Desaive, Thomas

    2016-05-01

    The six-chamber cardiovascular system model of Burkhoff and Tyberg has been used in several theoretical and experimental studies. However, this cardiovascular system model (and others derived from it) are not identifiable from any output set. In this work, two such cases of structural non-identifiability are first presented. These cases occur when the model output set only contains a single type of information (pressure or volume). A specific output set is thus chosen, mixing pressure and volume information and containing only a limited number of clinically available measurements. Then, by manipulating the model equations involving these outputs, it is demonstrated that the six-chamber cardiovascular system model is structurally globally identifiable. A further simplification is made, assuming known cardiac valve resistances. Because of the poor practical identifiability of these four parameters, this assumption is usual. Under this hypothesis, the six-chamber cardiovascular system model is structurally identifiable from an even smaller dataset. As a consequence, parameter values computed from limited but well-chosen datasets are theoretically unique. This means that the parameter identification procedure can safely be performed on the model from such a well-chosen dataset. Thus, the model may be considered suitable for use in diagnosis. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  14. An Application Of Receptor Modeling To Identify Airborne Particulate ...

    African Journals Online (AJOL)

    An Application Of Receptor Modeling To Identify Airborne Particulate Sources In Lagos, Nigeria. FS Olise, OK Owoade, HB Olaniyi. Abstract. There have been no clear demarcations between industrial and residential areas of Lagos with focus on industry as the major source. There is need to identify potential source types in ...

  15. Identifiability of Model Properties in Over-Parameterized Model Classes

    DEFF Research Database (Denmark)

    Jaeger, Manfred

    2013-01-01

    Classical learning theory is based on a tight linkage between hypothesis space (a class of function on a domain X), data space (function-value examples (x, f(x))), and the space of queries for the learned model (predicting function values for new examples x). However, in many learning scenarios t...

  16. Identifying the important factors in simulation models with many factors

    NARCIS (Netherlands)

    Bettonvil, B.; Kleijnen, J.P.C.

    1994-01-01

    Simulation models may have many parameters and input variables (together called factors), while only a few factors are really important (parsimony principle). For such models this paper presents an effective and efficient screening technique to identify and estimate those important factors. The

  17. Adolescent Boys, Embodied Heteromasculinities and Sexual Violence

    Science.gov (United States)

    Messerschmidt, James W.

    2017-01-01

    In this paper the author summarizes several life history case studies of adolescent boys who were identified at school as "wimps" and who eventually engaged in various forms of sexual violence. Such boys rarely are--if at all--discussed in the childhood, education and feminist literatures on sexual violence. The life stories reveal the…

  18. The Science of Little Boy

    Science.gov (United States)

    Askew, Jennifer; Gray, Ron

    2017-01-01

    Near the end of World War II, the United States dropped the first nuclear bomb ever used in warfare. The bomb was code named "Little Boy." The fission-type nuclear bomb exploded with the energy equivalent of approximately 13 kilotons of TNT. This article describes a 16 day model-based inquiry (MBI) unit on nuclear chemistry that…

  19. Identifying the connective strength between model parameters and performance criteria

    Directory of Open Access Journals (Sweden)

    B. Guse

    2017-11-01

    Full Text Available In hydrological models, parameters are used to represent the time-invariant characteristics of catchments and to capture different aspects of hydrological response. Hence, model parameters need to be identified based on their role in controlling the hydrological behaviour. For the identification of meaningful parameter values, multiple and complementary performance criteria are used that compare modelled and measured discharge time series. The reliability of the identification of hydrologically meaningful model parameter values depends on how distinctly a model parameter can be assigned to one of the performance criteria. To investigate this, we introduce the new concept of connective strength between model parameters and performance criteria. The connective strength assesses the intensity in the interrelationship between model parameters and performance criteria in a bijective way. In our analysis of connective strength, model simulations are carried out based on a latin hypercube sampling. Ten performance criteria including Nash–Sutcliffe efficiency (NSE, Kling–Gupta efficiency (KGE and its three components (alpha, beta and r as well as RSR (the ratio of the root mean square error to the standard deviation for different segments of the flow duration curve (FDC are calculated. With a joint analysis of two regression tree (RT approaches, we derive how a model parameter is connected to different performance criteria. At first, RTs are constructed using each performance criterion as the target variable to detect the most relevant model parameters for each performance criterion. Secondly, RTs are constructed using each parameter as the target variable to detect which performance criteria are impacted by changes in the values of one distinct model parameter. Based on this, appropriate performance criteria are identified for each model parameter. In this study, a high bijective connective strength between model parameters and performance criteria

  20. National Boy Scout Jamboree

    Science.gov (United States)

    1989-01-01

    This video looks at a NASA sponsored exhibit at the National Boy Scout Jamboree in Fredricksburg, VA. Boy Scouts are shown interacting with NASA researchers and astronauts and touring mockups of Space Station Freedom and Apollo 11. NASA's program to encourage the researchers of tomorrow is detailed.

  1. Turn Your Boys into Readers!

    Science.gov (United States)

    Allyn, Pam

    2011-01-01

    Girls outscore boys in reading proficiency levels; the gender gap is startling and concerning. The myth that boys won't read or that it's not "cool" for boys to love reading plays a big part in how these low levels come to be. Low expectations from teachers, and an assumption that boys prefer physical activity, mean that boys often don't find…

  2. Identifiability and error minimization of receptor model parameters with PET

    International Nuclear Information System (INIS)

    Delforge, J.; Syrota, A.; Mazoyer, B.M.

    1989-01-01

    The identifiability problem and the general framework for experimental design optimization are presented. The methodology is applied to the problem of the receptor-ligand model parameter estimation with dynamic positron emission tomography data. The first attempts to identify the model parameters from data obtained with a single tracer injection led to disappointing numerical results. The possibility of improving parameter estimation using a new experimental design combining an injection of the labelled ligand and an injection of the cold ligand (displacement experiment) has been investigated. However, this second protocol led to two very different numerical solutions and it was necessary to demonstrate which solution was biologically valid. This has been possible by using a third protocol including both a displacement and a co-injection experiment. (authors). 16 refs.; 14 figs

  3. 'Bad boys'' Bodies

    DEFF Research Database (Denmark)

    Skårderud, Finn; Nygren, Pär; Edlund, Birgitta

    2005-01-01

    (n= 196) completed the Eating Disorders Inventory ? Child version (EDI-C). The childcare residents also completed an extended questionnaire, including questions regarding the use of anabolic?andro-genic steroids. Our main ?ndings were high scores on EDI-C symptom scales for boys in the childcare...... resident group; few differences between girls in the two samples; and a high frequency of having used anabolic?androgenic steroids among boys in care. Body-image problems among boys have hitherto been given little attention. The results call for increased efforts in describing and detecting patho...

  4. Concerns Boys Have about Puberty

    Science.gov (United States)

    ... Size Email Print Share Concerns Boys Have About Puberty Page Content Article Body Boys have pubertal concerns ... just part of growing up. Involuntary Erections During puberty, boys get erections spontaneously, without touching their penis ...

  5. Prosocial And Antisocial Boys Together

    Science.gov (United States)

    Feldman, Ronald A.; And Others

    1973-01-01

    It may not help antisocial boys to segregate them, but wouldn't it harm prosocial boys to be integrated with antisocial boys? This study examines both propositions in the light of investigation at a summer camp. (Author)

  6. Modelling the regional application of stakeholder identified land management strategies.

    Science.gov (United States)

    Irvine, B. J.; Fleskens, L.; Kirkby, M. J.

    2012-04-01

    The DESIRE project has trialled a series of sustainable land management (SLM) technologies. These technologies have been identified as being beneficial in mitigating land degradation by local stakeholders from a range of semi-arid study sites. The field results and the qualitative WOCAT technology assessment ftom across the study sites have been used to develop the adapted PESERA SLM model. This paper considers the development of the adapted PESERA SLM model and the potential for applying locally successful SLM technologies across a wider range of climatic and environmental conditions with respect to degradation risk, biomass production and the investment cost interface (PESERA/DESMICE). The integrate PESERA/DESMICE model contributes to the policy debate by providing a biophysical and socio-economic assessment of technology and policy scenarios.

  7. The Relationship between Race and Students' Identified Career Role Models and Perceived Role Model Influence

    Science.gov (United States)

    Karunanayake, Danesh; Nauta, Margaret M.

    2004-01-01

    The authors examined whether college students' race was related to the modal race of their identified career role models, the number of identified career role models, and their perceived influence from such models. Consistent with A. Bandura's (1977, 1986) social learning theory, students tended to have role models whose race was the same as…

  8. Nurturing Environments for Boys and Men of Color with Trauma Exposure.

    Science.gov (United States)

    Graham, Phillip W; Yaros, Anna; Lowe, Ashley; McDaniel, Mark S

    2017-06-01

    Boys and men of color are exposed to traumatic experiences at significantly higher rates than are other demographic groups. To understand and address the mental and behavioral health effects of trauma, including violent incidents, on this population, we review the literature showing the context for, outcomes of, and potential responses to trauma exposure. We present the existing research about the unique challenges and associated negative outcomes for boys and men of color, as well as identify the gaps in the literature. We present the potential nurturing responses by systems such as schools, law enforcement, and communities to trauma-exposed boys and men of color, and we describe evidence-based programs and practices that directly address trauma. Finally, we argue that, rather than using a deficit model, a model of optimal development can be used to understand how to support and protect boys and men of color through nurturing environments.

  9. Adolescent Boys, Embodied Heteromasculinities and Sexual Violence

    Directory of Open Access Journals (Sweden)

    James W. Messerschmidt

    2017-06-01

    Full Text Available In this paper the author summarizes several life history case studies of adolescent boys who were identified at school as “wimps” and who eventually engaged in various forms of sexual violence. Such boys rarely are— if at all—discussed in the childhood, education and feminist literatures on sexual violence. The life stories reveal the interrelationship among inschool bullying, reflexivity, embodied structured action, and the social construction of heteromasculinities in the commission of sexual violence by subordinated boys. The author concludes by considering the implications the research has to the evolving discourses on social scientific conceptualizations of reflexive embodiment and heteromasculinities.

  10. [Anorexia nervosa in boys].

    Science.gov (United States)

    Dalem, I; Piccinin, B; Lerminiaux, D; Ansseau, M

    2000-12-01

    Anorexia nervosa is a severe and potentially fatal disorder that generally affects adolescent girls. However, a small number of boys also suffer from anorexia nervosa. Through an analysis of a series of studies and articles, a synthesis of male anorexia nervosa is offered, with emphasis on the differences of the illness between boys and girls. A clinical case is provided as an illustration of this article.

  11. The Effect of Puberty Health Education based on Health Belief Model on Health Behaviors and Preventive among Teen Boys in Marivan, North West of Iran

    Directory of Open Access Journals (Sweden)

    Rohollah Valizade

    2016-08-01

    Full Text Available Background Maturity and its related sexual and mental changes are one of the most important events in the life of every individual. The purpose of this study was to determine the effect of puberty health education based on Health Belief Model on health behaviors and preventive among students boy first secondary school in Marivan city in 2015. Materials and Methods This research is an experimental intervention study that was conducted in 2015. The study participants were 64 male students of second year of first secondary school boys who were selected randomly with cluster sampling from two schools among 12 schools in first grade of high school in the Marivan city. Totally 32 students were selected randomly in the intervention group in the one of the schools and 32 students in the control group in the other school. The data collection instrument was a questionnaire developed by the researchers based on the health belief model. The validity and reliability of questionnaire was confirmed. Statistical analysis was carried out using SPSS version 17, Chi square, descriptive statistics and independent t-tests. Results Results showed significance differences after educational intervention in the mean scores of awareness, perceived susceptibility, perceived severity, perceived benefits, cues to action and performance in the intervention group (p

  12. Drosophila Cancer Models Identify Functional Differences between Ret Fusions.

    Science.gov (United States)

    Levinson, Sarah; Cagan, Ross L

    2016-09-13

    We generated and compared Drosophila models of RET fusions CCDC6-RET and NCOA4-RET. Both RET fusions directed cells to migrate, delaminate, and undergo EMT, and both resulted in lethality when broadly expressed. In all phenotypes examined, NCOA4-RET was more severe than CCDC6-RET, mirroring their effects on patients. A functional screen against the Drosophila kinome and a library of cancer drugs found that CCDC6-RET and NCOA4-RET acted through different signaling networks and displayed distinct drug sensitivities. Combining data from the kinome and drug screens identified the WEE1 inhibitor AZD1775 plus the multi-kinase inhibitor sorafenib as a synergistic drug combination that is specific for NCOA4-RET. Our work emphasizes the importance of identifying and tailoring a patient's treatment to their specific RET fusion isoform and identifies a multi-targeted therapy that may prove effective against tumors containing the NCOA4-RET fusion. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Simple Model for Identifying Critical Regions in Atrial Fibrillation

    Science.gov (United States)

    Christensen, Kim; Manani, Kishan A.; Peters, Nicholas S.

    2015-01-01

    Atrial fibrillation (AF) is the most common abnormal heart rhythm and the single biggest cause of stroke. Ablation, destroying regions of the atria, is applied largely empirically and can be curative but with a disappointing clinical success rate. We design a simple model of activation wave front propagation on an anisotropic structure mimicking the branching network of heart muscle cells. This integration of phenomenological dynamics and pertinent structure shows how AF emerges spontaneously when the transverse cell-to-cell coupling decreases, as occurs with age, beyond a threshold value. We identify critical regions responsible for the initiation and maintenance of AF, the ablation of which terminates AF. The simplicity of the model allows us to calculate analytically the risk of arrhythmia and express the threshold value of transversal cell-to-cell coupling as a function of the model parameters. This threshold value decreases with increasing refractory period by reducing the number of critical regions which can initiate and sustain microreentrant circuits. These biologically testable predictions might inform ablation therapies and arrhythmic risk assessment.

  14. Rheumatoid arthritis: identifying and characterising polymorphisms using rat models

    Science.gov (United States)

    2016-01-01

    ABSTRACT Rheumatoid arthritis is a chronic inflammatory joint disorder characterised by erosive inflammation of the articular cartilage and by destruction of the synovial joints. It is regulated by both genetic and environmental factors, and, currently, there is no preventative treatment or cure for this disease. Genome-wide association studies have identified ∼100 new loci associated with rheumatoid arthritis, in addition to the already known locus within the major histocompatibility complex II region. However, together, these loci account for only a modest fraction of the genetic variance associated with this disease and very little is known about the pathogenic roles of most of the risk loci identified. Here, we discuss how rat models of rheumatoid arthritis are being used to detect quantitative trait loci that regulate different arthritic traits by genetic linkage analysis and to positionally clone the underlying causative genes using congenic strains. By isolating specific loci on a fixed genetic background, congenic strains overcome the challenges of genetic heterogeneity and environmental interactions associated with human studies. Most importantly, congenic strains allow functional experimental studies be performed to investigate the pathological consequences of natural genetic polymorphisms, as illustrated by the discovery of several major disease genes that contribute to arthritis in rats. We discuss how these advances have provided new biological insights into arthritis in humans. PMID:27736747

  15. A Cypriote boy

    OpenAIRE

    Thomson, John, 1837-1921, photographer

    2003-01-01

    90 x 110 mm. Woodburytype. A half-length portrait of a young boy. The portrait appears in Thomson's 'Through Cyprus with the camera, in the autumn of 1878' (vol.2, London: Sampson Low, Marston, Searle, and Rivington, 1879). Thomson wrote: 'The boy represented in the second picture is the son of the priest of Avgoru [? Avgorou]. The higher dignitaries of the Greek Church are not permitted to marry; but the papa may be wedded, subject to the condition that the union was effected before his...

  16. Modeling secondary accidents identified by traffic shock waves.

    Science.gov (United States)

    Junhua, Wang; Boya, Liu; Lanfang, Zhang; Ragland, David R

    2016-02-01

    The high potential for occurrence and the negative consequences of secondary accidents make them an issue of great concern affecting freeway safety. Using accident records from a three-year period together with California interstate freeway loop data, a dynamic method for more accurate classification based on the traffic shock wave detecting method was used to identify secondary accidents. Spatio-temporal gaps between the primary and secondary accident were proven be fit via a mixture of Weibull and normal distribution. A logistic regression model was developed to investigate major factors contributing to secondary accident occurrence. Traffic shock wave speed and volume at the occurrence of a primary accident were explicitly considered in the model, as a secondary accident is defined as an accident that occurs within the spatio-temporal impact scope of the primary accident. Results show that the shock waves originating in the wake of a primary accident have a more significant impact on the likelihood of a secondary accident occurrence than the effects of traffic volume. Primary accidents with long durations can significantly increase the possibility of secondary accidents. Unsafe speed and weather are other factors contributing to secondary crash occurrence. It is strongly suggested that when police or rescue personnel arrive at the scene of an accident, they should not suddenly block, decrease, or unblock the traffic flow, but instead endeavor to control traffic in a smooth and controlled manner. Also it is important to reduce accident processing time to reduce the risk of secondary accident. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Identifiability of Baranyi model and comparison with empirical ...

    African Journals Online (AJOL)

    In addition, performance of the Baranyi model was compared with those of the empirical modified Gompertz and logistic models and Huang models. Higher values of R2, modeling efficiency and lower absolute values of mean bias error, root mean square error, mean percentage error and chi-square were obtained with ...

  18. Friendship in school-age boys with autism spectrum disorders: A meta-analytic summary and developmental, process-based model.

    Science.gov (United States)

    Mendelson, Jenna L; Gates, Jacquelyn A; Lerner, Matthew D

    2016-06-01

    Friendship-making is considered a well-established domain of deficit for children with autism spectrum disorders (ASD; American Psychiatric Association, 2013), with this population sometimes described as incapable of making friends. However, the majority of children with ASD indicate a desire for friends, and many report having friends. To what degree, then, do youth with ASD succeed in achieving friendships with peers? If and when they do succeed, by what means do these friendships emerge relative to models of typically developing (TD) youths' friendships? To address these questions, we first meta-analyzed the descriptive friendship literature (peer-reported sociometrics, self-report, parent-report) among school-age boys with ASD. Using random effects models, we found that youth with ASD do make friends according to peers and parents (Hedges's g > 2.84). However, self-reported friendship quality (Hedges's g = -1.09) and parent- and peer-reported quantity (Hedges's g friendship in TD youth (Hartup & Stevens, 1997). We then present a model that synthesizes these domains through the construct of social information processing speed, and thereby present the first developmental, process-based model of friendship development among youth with ASD. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. An improved model for identifying influential bloggers on the web ...

    African Journals Online (AJOL)

    The benefits of achieving competitive advantages in a blog community by identify influential blogger have created several research gaps and the popularity of these services has make the problem of identifying the most influential bloggers noteworthy, since its solution can lead to major benefits for the users of this services ...

  20. Predicting the onset of smoking in boys and girls.

    Science.gov (United States)

    Charlton, A; Blair, V

    1989-01-01

    The problem of the high prevalence of smoking among girls and young women is of great concern. In an attempt to identify the factors which influence girls and boys respectively to attempt smoking, the study examines social background, advertising and brand awareness, knowledge, teaching and personal beliefs in conjunction as predictors of smoking. In this study which involved the administration of identical pre- and post-test questionnaires to a sample of boys and girls aged 12 and 13 years, nine variables expressed by never-smokers at pre-test stage were assessed as predictors of immediate future smoking. The two tests were administered 4 months apart to 1125 boys and 1213 girls in northern England. The nine variables included were parental smoking, best friends' smoking, perceived positive values of smoking, perceived negative values of smoking, correct health knowledge, cigarette-brand awareness, having a favourite cigarette advertisement, having a cigarette-brand sponsored sport in four top favourites on television. One group received teaching about smoking between the pre- and post-tests and this was also included as a variable. For boys, no variable investigated had any consistently statistically significant correlation with the uptake of smoking. The most important predictor of smoking for boys, having a best friend who smoked, was significant on application of the chi 2 test (P 0.037), although it was non-significant when included singly in a logistic regression model (0.094); the discrepancy was probably due to the small number of best friends known to smoke. For girls, four variables were found to be significant predictors of smoking when included singly in a logistic regression.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. [Girls are more successful than boys at the university. Gender group differences in models integrating motivational and aggressive components correlated with Test-Anxiety].

    Science.gov (United States)

    Masson, A-M; Hoyois, Ph; Cadot, M; Nahama, V; Petit, F; Ansseau, M

    2004-01-01

    performance value were scored higher in women, self-confidence and procrastination higher in men. Because TASTE didn't discriminate the different components of motivation (performance value referred to intrinsic and extrinsic motivations without precise distinction) we decided to use the MPS (Multidimensional Perfectionism Scale) which gave the opportunity to distinguish SOP (Self Oriented Perfectionism) ie, the self-imposed unrealistic standards with inability to accept faults in order to know and master a subject, that corresponded to intrinsic motivation; SPP (Socially Prescribed Perfectionism) ie, the exaggerated expectancies of others which are subjectively believed as imposed and uncontrollable leading to anxiety, feelings of failure or helplessness, that corresponded to extrinsic motivation; POO (Perfectionism Oriented to Others) ie, the unrealistic demands expected from significant others, which especially characterized males. We assumed that women attached more importance to succeed and submitted more to society exigencies. That way extrinsic and intrinsic motivations were probably more combined unlike men who, dreading a loss of self esteem, tried to avoid failure responsibility in using self handicapping or aggressive behaviours, so separating motivation in an extrinsic part turned to performance value and an intrinsic one more concerned by self confidence and sense of competence with the result that the motivational balance was surely disrupted in case of high competition leading to failure or avoidance. In another previous study we established a structural model illustrating, according to gender, correlations between anxiety, sense of incompetence, self-oriented perfectionism and socially prescribed perfectionism. Self-oriented perfectionism was less correlated to socially prescribed perfectionism in boys than in girls; furthermore especially by those who had never failed, it was negatively correlated to sense of incompetence, thus leading to lower scores of

  2. Boys' Bodies in Early Childhood

    Science.gov (United States)

    Drummond, Murray

    2012-01-01

    This paper is based on qualitative research data from a project investigating early childhood boys' constructions of masculinities in relation to sport, health and the body. The focus group data, with 33 boys, has been collected in each of the boys' first three years at school. It is part of the data that will be collected over eight years with…

  3. Family and personal characteristics of aggressive Nigerian boys: differences from and similarities with Western findings.

    Science.gov (United States)

    Ani, C C; Grantham-McGregor, S

    1998-11-01

    To identify the family and child determinants of aggressive behaviour in Nigerian elementary school boys and to compare the findings with previous ones from Western studies. Forty-seven aggressive boys from four elementary schools in Lagos, Nigeria were compared with 47 matched pro-social boys. Teacher rating and peer nomination were combined to select subjects. The subjects and their parents were given structured questionnaires to obtain information on possible risk factors for aggression. Compared with pro-social boys, it was found that significantly more aggressive boys came from polygamous families and crowded homes, had more siblings, received less parental affection, were more physically punished, less supervised at home, witnessed more domestic conflicts, did poorly at school, had poorer verbal intelligence and attributed malice more readily than pro-social boys. Logistic regression indicated that the independent family predictors of aggression were crowding, little paternal affection, and corporal punishment. The independent child predictors were biased attribution and poor school achievement. Corporal punishment at school was also an independent predictor of aggression. The family and child determinants of aggressive behaviour in Nigeria are similar to those found in Western studies except for the small contribution of family instability and overwhelming influence of corporal punishment in our sample. Models of intervention developed in the West may therefore be cautiously applied to Nigerian children.

  4. Modelling intelligence-led policing to identify its potential

    NARCIS (Netherlands)

    Hengst-Bruggeling, M. den; Graaf, H.A.L.M. de; Scheepstal, P.G.M. van

    2014-01-01

    lntelligence-led policing is a concept of policing that has been applied throughout the world. Despite some encouraging reports, the effect of intelligence-led policing is largely unknown. This paper presents a method with which it is possible to identify intelligence-led policing's potential to

  5. Modelling discontinuous well log signal to identify lithological ...

    Indian Academy of Sciences (India)

    1Indian School of Mines (ISM), Dhanbad 826 004, India. ... new wavelet transform-based algorithm to model the abrupt discontinuous changes from well log data by taking care of ...... the 11th ACM International Conference on Multimedia,.

  6. A Method to Identify Flight Obstacles on Digital Surface Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Min; LIN Xinggang; SUN Shouyu; WANG Youzhi

    2005-01-01

    In modern low-altitude terrain-following guidance, a constructing method of the digital surface model (DSM) is presented in the paper to reduce the threat to flying vehicles of tall surface features for safe flight. The relationship between an isolated obstacle size and the intervals of vertical- and cross-section in the DSM model is established. The definition and classification of isolated obstacles are proposed, and a method for determining such isolated obstacles in the DSM model is given. The simulation of a typical urban district shows that when the vertical- and cross-section DSM intervals are between 3 m and 25 m, the threat to terrain-following flight at low-altitude is reduced greatly, and the amount of data required by the DSM model for monitoring in real time a flying vehicle is also smaller. Experiments show that the optimal results are for an interval of 12.5 m in the vertical- and cross-sections in the DSM model, with a 1:10 000 DSM scale grade.

  7. A preliminary model to identify low-risk MBA applicants

    Directory of Open Access Journals (Sweden)

    CA Bisschoff

    2014-08-01

    The reliability of the discriminant function rates favourably with 71% (MBA in 3 years, 62% (MBA in 4 years and 83% (dropping out of the programme being categorised correctly by the respective discriminant functions. Being a preliminary model, its predictive capabilities need to be verified in practice before it can  be implemented as tool to render assistance in MBA admissions.  The value of this research lies  in the fact that it constitutes a model that could be employed and improved as a predictive tool in an environment where very limited predictive tools exist.  Therefore, although it is by no means a tried and tested model, it sets the scene by supplying a scientific base from which incremental improvements could result.

  8. Identifying Clusters with Mixture Models that Include Radial Velocity Observations

    Science.gov (United States)

    Czarnatowicz, Alexis; Ybarra, Jason E.

    2018-01-01

    The study of stellar clusters plays an integral role in the study of star formation. We present a cluster mixture model that considers radial velocity data in addition to spatial data. Maximum likelihood estimation through the Expectation-Maximization (EM) algorithm is used for parameter estimation. Our mixture model analysis can be used to distinguish adjacent or overlapping clusters, and estimate properties for each cluster.Work supported by awards from the Virginia Foundation for Independent Colleges (VFIC) Undergraduate Science Research Fellowship and The Research Experience @Bridgewater (TREB).

  9. Genome-wide association study to identify potential genetic modifiers in a canine model for Duchenne muscular dystrophy.

    Science.gov (United States)

    Brinkmeyer-Langford, Candice; Balog-Alvarez, Cynthia; Cai, James J; Davis, Brian W; Kornegay, Joe N

    2016-08-22

    Duchenne muscular dystrophy (DMD) causes progressive muscle degeneration, cardiomyopathy and respiratory failure in approximately 1/5,000 boys. Golden Retriever muscular dystrophy (GRMD) resembles DMD both clinically and pathologically. Like DMD, GRMD exhibits remarkable phenotypic variation among affected dogs, suggesting the influence of modifiers. Understanding the role(s) of genetic modifiers of GRMD may identify genes and pathways that also modify phenotypes in DMD and reveal novel therapies. Therefore, our objective in this study was to identify genetic modifiers that affect discrete GRMD phenotypes. We performed a linear mixed-model (LMM) analysis using 16 variably-affected dogs from our GRMD colony (8 dystrophic, 8 non-dystrophic). All of these dogs were either full or half-siblings, and phenotyped for 19 objective, quantitative biomarkers at ages 6 and 12 months. Each biomarker was individually assessed. Gene expression profiles of 59 possible candidate genes were generated for two muscle types: the cranial tibialis and medial head of the gastrocnemius. SNPs significantly associated with GRMD biomarkers were identified on multiple chromosomes (including the X chromosome). Gene expression levels for candidate genes located near these SNPs correlated with biomarker values, suggesting possible roles as GRMD modifiers. The results of this study enhance our understanding of GRMD pathology and represent a first step toward the characterization of GRMD modifiers that may be relevant to DMD pathology. Such modifiers are likely to be useful for DMD treatment development based on their relationships to GRMD phenotypes.

  10. A bibliometric model for identifying emerging research topics

    DEFF Research Database (Denmark)

    Wang, Qi

    2018-01-01

    –1843, 2015), the most serious problems are the lack of an acknowledged definition of emergence and incomplete elaboration of the linkages between the definitions that are used and the indicators that are created. With these issues in mind, this study first adjusts the definition of an emerging technology...... that Rotolo et al. (2015) have proposed to accommodate the analysis. Next, a set of criteria for the identification of emerging topics is proposed according to the adjusted definition and attributes of emergence. Using two sets of parameter values, several emerging research topics are identified. Finally...

  11. Modeling of CPDOs - Identifying Optimal and Implied Leverage

    DEFF Research Database (Denmark)

    Dorn, Jochen

    famous notably by Standard & Poor's rating model error which illustrated that closed-form analytical pricing is necessary in order to evaluate and understand complex derivatives. This article aims to shed a light on CPDOs specific structural enhancements and mechanisms. The author quantifies inherent...... risks and provides a dynamic closed-form pricing formula....

  12. Modeling of CPDOs - Identifying optimal and implied leverage

    DEFF Research Database (Denmark)

    Dorn, Jochen

    2010-01-01

    by Standard & Poor's rating model error which illustrated that closed-form analytical pricing is necessary in order to evaluate and understand complex derivatives. This article aims to shed a light on CPDOs' specific structural enhancements and mechanisms. We quantify inherent risks and provide a dynamic...

  13. A computer model for identifying security system upgrades

    International Nuclear Information System (INIS)

    Lamont, A.

    1988-01-01

    This paper describes a prototype safeguards analysis tool that automatically identifies system weaknesses against an insider adversary and suggest possible upgrades to improve the probability that the adversary will be detected. The tool is based on this premise: as the adversary acts, he or she creates a set of facts that can be detected by safeguards components. Whenever an adversary's planned set of actions create a set of facts which the security personnel would consider irregular or unusual, we can improve the security system by implementing safeguards that detect those facts. Therefore, an intelligent computer program can suggest upgrades to the facility if we construct a knowledge base that contains information about: (1) the facts created by each possible adversary action, (2) the facts that each possible safeguard can detect, and (3) groups of facts which will be considered irregular whenever they occur together. The authors describe the structure of the knowledge base and show how the above information can be represented in it. They also describe the procedures that a computer program can use to identify missing or weak safeguards and to suggest upgrades

  14. Identifying traffic accident black spots with Poisson-Tweedie models

    DEFF Research Database (Denmark)

    Debrabant, Birgit; Halekoh, Ulrich; Bonat, Wagner Hugo

    2018-01-01

    This paper aims at the identification of black spots for traffic accidents, i.e. locations with accident counts beyond what is usual for similar locations, using spatially and temporally aggregated hospital records from Funen, Denmark. Specifically, we apply an autoregressive Poisson-Tweedie model...... considered calendar years and calculated by simulations a probability of p=0.03 for these to be chance findings. Altogether, our results recommend these sites for further investigation and suggest that our simple approach could play a role in future area based traffic accident prevention planning....

  15. Identifying the Source of Misfit in Item Response Theory Models.

    Science.gov (United States)

    Liu, Yang; Maydeu-Olivares, Alberto

    2014-01-01

    When an item response theory model fails to fit adequately, the items for which the model provides a good fit and those for which it does not must be determined. To this end, we compare the performance of several fit statistics for item pairs with known asymptotic distributions under maximum likelihood estimation of the item parameters: (a) a mean and variance adjustment to bivariate Pearson's X(2), (b) a bivariate subtable analog to Reiser's (1996) overall goodness-of-fit test, (c) a z statistic for the bivariate residual cross product, and (d) Maydeu-Olivares and Joe's (2006) M2 statistic applied to bivariate subtables. The unadjusted Pearson's X(2) with heuristically determined degrees of freedom is also included in the comparison. For binary and ordinal data, our simulation results suggest that the z statistic has the best Type I error and power behavior among all the statistics under investigation when the observed information matrix is used in its computation. However, if one has to use the cross-product information, the mean and variance adjusted X(2) is recommended. We illustrate the use of pairwise fit statistics in 2 real-data examples and discuss possible extensions of the current research in various directions.

  16. Identifying missing dictionary entries with frequency-conserving context models

    Science.gov (United States)

    Williams, Jake Ryland; Clark, Eric M.; Bagrow, James P.; Danforth, Christopher M.; Dodds, Peter Sheridan

    2015-10-01

    In an effort to better understand meaning from natural language texts, we explore methods aimed at organizing lexical objects into contexts. A number of these methods for organization fall into a family defined by word ordering. Unlike demographic or spatial partitions of data, these collocation models are of special importance for their universal applicability. While we are interested here in text and have framed our treatment appropriately, our work is potentially applicable to other areas of research (e.g., speech, genomics, and mobility patterns) where one has ordered categorical data (e.g., sounds, genes, and locations). Our approach focuses on the phrase (whether word or larger) as the primary meaning-bearing lexical unit and object of study. To do so, we employ our previously developed framework for generating word-conserving phrase-frequency data. Upon training our model with the Wiktionary, an extensive, online, collaborative, and open-source dictionary that contains over 100 000 phrasal definitions, we develop highly effective filters for the identification of meaningful, missing phrase entries. With our predictions we then engage the editorial community of the Wiktionary and propose short lists of potential missing entries for definition, developing a breakthrough, lexical extraction technique and expanding our knowledge of the defined English lexicon of phrases.

  17. Understanding the Day Cent model: Calibration, sensitivity, and identifiability through inverse modeling

    Science.gov (United States)

    Necpálová, Magdalena; Anex, Robert P.; Fienen, Michael N.; Del Grosso, Stephen J.; Castellano, Michael J.; Sawyer, John E.; Iqbal, Javed; Pantoja, Jose L.; Barker, Daniel W.

    2015-01-01

    The ability of biogeochemical ecosystem models to represent agro-ecosystems depends on their correct integration with field observations. We report simultaneous calibration of 67 DayCent model parameters using multiple observation types through inverse modeling using the PEST parameter estimation software. Parameter estimation reduced the total sum of weighted squared residuals by 56% and improved model fit to crop productivity, soil carbon, volumetric soil water content, soil temperature, N2O, and soil3NO− compared to the default simulation. Inverse modeling substantially reduced predictive model error relative to the default model for all model predictions, except for soil 3NO− and 4NH+. Post-processing analyses provided insights into parameter–observation relationships based on parameter correlations, sensitivity and identifiability. Inverse modeling tools are shown to be a powerful way to systematize and accelerate the process of biogeochemical model interrogation, improving our understanding of model function and the underlying ecosystem biogeochemical processes that they represent.

  18. Developmental Trajectories of Girls' and Boys' Delinquency and Associated Problems

    Science.gov (United States)

    Pepler, Debra J.; Jiang, Depeng; Craig, Wendy M.; Connolly, Jennifer

    2010-01-01

    Developmental trajectories in delinquency through adolescence were studied along with family and peer relationship problems. Drawing from eight waves of data over seven years, we conducted trajectory analyses with a sample of 746 students (402 girls; 344 boys). Analyzing girls and boys together, a five-class model emerged: 60% of the adolescents…

  19. The Non-Fiction Reading Habits of Young Successful Boy Readers: Forming Connections between Masculinity and Reading

    Science.gov (United States)

    Smith, Susannah

    2004-01-01

    The reading experiences of six young successful boy readers were studied over a two-year period. In this article, their non-fiction reading is analysed and ways in which the boys make positive connections between masculinity and reading are identified. The boys' non-fiction reading centres on typical boy interest areas and hobbies (for example,…

  20. Assessing Reliability of Cellulose Hydrolysis Models to Support Biofuel Process Design – Identifiability and Uncertainty Analysis

    DEFF Research Database (Denmark)

    Sin, Gürkan; Meyer, Anne S.; Gernaey, Krist

    2010-01-01

    The reliability of cellulose hydrolysis models is studied using the NREL model. An identifiability analysis revealed that only 6 out of 26 parameters are identifiable from the available data (typical hydrolysis experiments). Attempting to identify a higher number of parameters (as done in the ori......The reliability of cellulose hydrolysis models is studied using the NREL model. An identifiability analysis revealed that only 6 out of 26 parameters are identifiable from the available data (typical hydrolysis experiments). Attempting to identify a higher number of parameters (as done...

  1. Serving Boys through Readers' Advisory

    Science.gov (United States)

    Sullivan, Michael

    2010-01-01

    Based on more than twenty years' experience working to get boys interested in reading, the author now offers his first readers' advisory volume. With an emphasis on nonfiction and the boy-friendly categories of genre fiction, the work offers a wealth of material including: (1) Suggestions for how to booktalk one-on-one as well as in large groups;…

  2. Primary Boys and Hegemonic Masculinities.

    Science.gov (United States)

    Skelton, Christine

    1997-01-01

    Explores the relationships between primary-aged boys, hegemonic masculinities, and sexualized/violent behaviors in the school setting. Shows that hegemonic masculinities vary from school to school and that boys draw upon, negotiate, and reject aspects of the hegemonic masculinity of the school in the process of constructing their masculine…

  3. Boys and Puberty (For Kids)

    Science.gov (United States)

    ... Videos for Educators Search English Español Boys and Puberty KidsHealth / For Kids / Boys and Puberty What's in this article? Why Are Girls Taller ... as you grow up, especially as you reach puberty (say: PYOO-bur-tee), the name for the ...

  4. Creating developmentally auspicious school environments for African American boys.

    Science.gov (United States)

    Barbarin, Oscar A; Chinn, Lisa; Wright, Yamanda F

    2014-01-01

    African American (AA) boys face serious barriers to academic success, many of which are uncommon--or absent--in the lives of AA girls, other children of color, and European American children. In this chapter, we identify nine critical challenges to the successful education of AA boys and review possible solutions. In addition, we evaluate one particular reform, public single-sex schooling, as a possible solution to the challenges facing AA boys. Considering the evidence, we argue that recent efforts to expand the existence of public single-sex schools are rarely grounded in empirical findings. Given the lack of compelling evidence and the high stakes for AA boys, we call for more rigorous evaluations of the outcomes of sex-segregated programs that specifically target AA boys.

  5. Global identifiability of linear compartmental models--a computer algebra algorithm.

    Science.gov (United States)

    Audoly, S; D'Angiò, L; Saccomani, M P; Cobelli, C

    1998-01-01

    A priori global identifiability deals with the uniqueness of the solution for the unknown parameters of a model and is, thus, a prerequisite for parameter estimation of biological dynamic models. Global identifiability is however difficult to test, since it requires solving a system of algebraic nonlinear equations which increases both in nonlinearity degree and number of terms and unknowns with increasing model order. In this paper, a computer algebra tool, GLOBI (GLOBal Identifiability) is presented, which combines the topological transfer function method with the Buchberger algorithm, to test global identifiability of linear compartmental models. GLOBI allows for the automatic testing of a priori global identifiability of general structure compartmental models from general multi input-multi output experiments. Examples of usage of GLOBI to analyze a priori global identifiability of some complex biological compartmental models are provided.

  6. Some boys' problems in education

    DEFF Research Database (Denmark)

    Jørgensen, Christian Helms

    2015-01-01

    of education policy. The purpose of this article is to examine this ‘boy problem’ in relation to the dual system of vocational education and training (VET) in Denmark. By considering the gender divisions and the value of the VET programmes on the labour market, it explores what kind of problems boys have......The last two decades have seen an increasing political concern in the high dropout rates and low performance in education of boys compared to girls – at times in the form of a ‘moral panic’. This has also been the case in Denmark where ‘the boy problem’ in education now is placed high on the agenda...... to general education, but social and institutional processes of differentiation in the vocational schools place a significant group of students in a position where they have little chance of completing the programme. In the conclusion, some reflections are made on the effect of a recent reform of VET...

  7. Testicular biopsy in prepubertal boys

    DEFF Research Database (Denmark)

    Faure, Alice; Bouty, Aurore; O'Brien, Mike

    2016-01-01

    No consensus exists regarding the precise role of testicular biopsy in prepubertal boys, although it is considered useful for assessing the potential consequences of undescended testes on fertility. Current scientific knowledge indicates that surgeons should broaden indications for this procedure...... for the preservation of fertility after gonadotoxic chemotherapy - even for prepubertal boys - are emerging. Cryopreservation of testicular tissue samples for the preservation of fertility - although still an experimental method at present - is appealing in this context. In our opinion, testicular biopsy...

  8. Timing of Puberty in Overweight Versus Obese Boys.

    Science.gov (United States)

    Lee, Joyce M; Wasserman, Richard; Kaciroti, Niko; Gebremariam, Achamyeleh; Steffes, Jennifer; Dowshen, Steven; Harris, Donna; Serwint, Janet; Abney, Dianna; Smitherman, Lynn; Reiter, Edward; Herman-Giddens, Marcia E

    2016-02-01

    Studies of the relationship of weight status with timing of puberty in boys have been mixed. This study examined whether overweight and obesity are associated with differences in the timing of puberty in US boys. We reanalyzed recent community-based pubertal data from the American Academy of Pediatrics' Pediatric Research in Office Settings study in which trained clinicians assessed boys 6 to 16 years for height, weight, Tanner stages, testicular volume (TV), and other pubertal variables. We classified children based on BMI as normal weight, overweight, or obese and compared median age at a given Tanner stage or greater by weight class using probit and ordinal probit models and a Bayesian approach. Half of boys (49.9%, n = 1931) were white, 25.8% (n = 1000) were African American, and 24.3% (n = 941) were Hispanic. For genital development in white and African American boys across a variety of Tanner stages, we found earlier puberty in overweight compared with normal weight boys, and later puberty in obese compared with overweight, but no significant differences for Hispanics. For TV (≥3 mL or ≥4 mL), our findings support earlier puberty for overweight compared with normal weight white boys. In a large, racially diverse, community-based sample of US boys, we found evidence of earlier puberty for overweight compared with normal or obese, and later puberty for obese boys compared with normal and overweight boys. Additional studies are needed to understand the possible relationships among race/ethnicity, gender, BMI, and the timing of pubertal development. Copyright © 2016 by the American Academy of Pediatrics.

  9. Three novel approaches to structural identifiability analysis in mixed-effects models.

    Science.gov (United States)

    Janzén, David L I; Jirstrand, Mats; Chappell, Michael J; Evans, Neil D

    2016-05-06

    Structural identifiability is a concept that considers whether the structure of a model together with a set of input-output relations uniquely determines the model parameters. In the mathematical modelling of biological systems, structural identifiability is an important concept since biological interpretations are typically made from the parameter estimates. For a system defined by ordinary differential equations, several methods have been developed to analyse whether the model is structurally identifiable or otherwise. Another well-used modelling framework, which is particularly useful when the experimental data are sparsely sampled and the population variance is of interest, is mixed-effects modelling. However, established identifiability analysis techniques for ordinary differential equations are not directly applicable to such models. In this paper, we present and apply three different methods that can be used to study structural identifiability in mixed-effects models. The first method, called the repeated measurement approach, is based on applying a set of previously established statistical theorems. The second method, called the augmented system approach, is based on augmenting the mixed-effects model to an extended state-space form. The third method, called the Laplace transform mixed-effects extension, is based on considering the moment invariants of the systems transfer function as functions of random variables. To illustrate, compare and contrast the application of the three methods, they are applied to a set of mixed-effects models. Three structural identifiability analysis methods applicable to mixed-effects models have been presented in this paper. As method development of structural identifiability techniques for mixed-effects models has been given very little attention, despite mixed-effects models being widely used, the methods presented in this paper provides a way of handling structural identifiability in mixed-effects models previously not

  10. An effective automatic procedure for testing parameter identifiability of HIV/AIDS models.

    Science.gov (United States)

    Saccomani, Maria Pia

    2011-08-01

    Realistic HIV models tend to be rather complex and many recent models proposed in the literature could not yet be analyzed by traditional identifiability testing techniques. In this paper, we check a priori global identifiability of some of these nonlinear HIV models taken from the recent literature, by using a differential algebra algorithm based on previous work of the author. The algorithm is implemented in a software tool, called DAISY (Differential Algebra for Identifiability of SYstems), which has been recently released (DAISY is freely available on the web site http://www.dei.unipd.it/~pia/ ). The software can be used to automatically check global identifiability of (linear and) nonlinear models described by polynomial or rational differential equations, thus providing a general and reliable tool to test global identifiability of several HIV models proposed in the literature. It can be used by researchers with a minimum of mathematical background.

  11. A simple method for identifying parameter correlations in partially observed linear dynamic models.

    Science.gov (United States)

    Li, Pu; Vu, Quoc Dong

    2015-12-14

    Parameter estimation represents one of the most significant challenges in systems biology. This is because biological models commonly contain a large number of parameters among which there may be functional interrelationships, thus leading to the problem of non-identifiability. Although identifiability analysis has been extensively studied by analytical as well as numerical approaches, systematic methods for remedying practically non-identifiable models have rarely been investigated. We propose a simple method for identifying pairwise correlations and higher order interrelationships of parameters in partially observed linear dynamic models. This is made by derivation of the output sensitivity matrix and analysis of the linear dependencies of its columns. Consequently, analytical relations between the identifiability of the model parameters and the initial conditions as well as the input functions can be achieved. In the case of structural non-identifiability, identifiable combinations can be obtained by solving the resulting homogenous linear equations. In the case of practical non-identifiability, experiment conditions (i.e. initial condition and constant control signals) can be provided which are necessary for remedying the non-identifiability and unique parameter estimation. It is noted that the approach does not consider noisy data. In this way, the practical non-identifiability issue, which is popular for linear biological models, can be remedied. Several linear compartment models including an insulin receptor dynamics model are taken to illustrate the application of the proposed approach. Both structural and practical identifiability of partially observed linear dynamic models can be clarified by the proposed method. The result of this method provides important information for experimental design to remedy the practical non-identifiability if applicable. The derivation of the method is straightforward and thus the algorithm can be easily implemented into a

  12. Identifiability in N-mixture models: a large-scale screening test with bird data.

    Science.gov (United States)

    Kéry, Marc

    2018-02-01

    Binomial N-mixture models have proven very useful in ecology, conservation, and monitoring: they allow estimation and modeling of abundance separately from detection probability using simple counts. Recently, doubts about parameter identifiability have been voiced. I conducted a large-scale screening test with 137 bird data sets from 2,037 sites. I found virtually no identifiability problems for Poisson and zero-inflated Poisson (ZIP) binomial N-mixture models, but negative-binomial (NB) models had problems in 25% of all data sets. The corresponding multinomial N-mixture models had no problems. Parameter estimates under Poisson and ZIP binomial and multinomial N-mixture models were extremely similar. Identifiability problems became a little more frequent with smaller sample sizes (267 and 50 sites), but were unaffected by whether the models did or did not include covariates. Hence, binomial N-mixture model parameters with Poisson and ZIP mixtures typically appeared identifiable. In contrast, NB mixtures were often unidentifiable, which is worrying since these were often selected by Akaike's information criterion. Identifiability of binomial N-mixture models should always be checked. If problems are found, simpler models, integrated models that combine different observation models or the use of external information via informative priors or penalized likelihoods, may help. © 2017 by the Ecological Society of America.

  13. "We don't need no education": Video game preferences, video game motivations, and aggressiveness among adolescent boys of different educational ability levels.

    Science.gov (United States)

    Nije Bijvank, Marije; Konijn, Elly A; Bushman, Brad J

    2012-02-01

    This research focuses on low educational ability as a risk factor for aggression and violent game play. We propose that boys of lower educational ability are more attracted to violent video games than other boys are, and that they are also higher in trait aggressiveness and sensation seeking. Participants were Dutch boys in public schools (N = 830, age-range 11-17). In the Netherlands, standardized tests are used to place students into lower, medium, and higher educational ability groups. Results showed that boys in the lower educational ability group preferred to play violent, stand-alone games, identified more with video game characters, and perceived video games to be more realistic than other boys did. Lower levels of education were also related to higher levels of aggressiveness and sensation seeking. Higher educational ability boys preferred social, multiplayer games. Within a risk and resilience model, boys with lower educational ability are at greater risk for aggression. Copyright © 2011 The Foundation for Professionals in Services for Adolescents. All rights reserved.

  14. Bayesian inference for partially identified models exploring the limits of limited data

    CERN Document Server

    Gustafson, Paul

    2015-01-01

    Introduction Identification What Is against Us? What Is for Us? Some Simple Examples of Partially Identified ModelsThe Road Ahead The Structure of Inference in Partially Identified Models Bayesian Inference The Structure of Posterior Distributions in PIMs Computational Strategies Strength of Bayesian Updating, Revisited Posterior MomentsCredible Intervals Evaluating the Worth of Inference Partial Identification versus Model Misspecification The Siren Call of Identification Comp

  15. Cephalometric norms of Saudi boys

    International Nuclear Information System (INIS)

    Nashashibi, I. A.; Shaikh, H. S.; Sarhan, O. A.

    1990-01-01

    The present study was conducted to establish cephalometric norms of Saudi boys based on the Steiners analysis, and to compare the results of the present study with similar studies conducted on other racial or ethnic groups. For this purpose, fifty-five healthy Saudi boys, with a mean age of 12.04 years, were selected from different schools of Riyadh. Female Saudis were not used for this study due to social restrictions with respect to the Kingdom's customs and traditions. Selection was made on the basis of normal occlusion, balanced and pleasing profile with no obvious facial asymmetry. None of the boys have undergone orthodontic treatment prior to this study. Lateral skull cephaiograms were taken and traced using a standardized technique. Each cephalogram was traced twice with a one week interval by the authors. All angular and linear measurements were calculated to the nearest 0.5 degree and 0.5 mm, respectively. Steiners method of cephalometric analysis was used to establish cephalometric norms. The result of the study demonstrated that the Saudi boys differed from other racial and ethnic groups in some skeletal and dental measurements. Generally, the Saudi boys revealed a more protrusive maxillary apical base and double dental protrusion. (author)

  16. Mediators of Psychological Well-being in Adolescent Boys.

    Science.gov (United States)

    Lubans, David R; Smith, Jordan J; Morgan, Philip J; Beauchamp, Mark R; Miller, Andrew; Lonsdale, Chris; Parker, Philip; Dally, Kerry

    2016-02-01

    The aim of this study was to explore the effect of the Active Teen Leaders Avoiding Screen-time (ATLAS) intervention on psychological well-being in adolescent boys and to examine the potential mediating mechanisms that might explain this effect. ATLAS was evaluated using a cluster randomized controlled trial in 14 secondary schools located in low-income communities (N = 361 adolescent boys, mean age = 12.7 ± .5 years). The 20-week intervention was guided by self-determination theory and involved: professional development for teachers, provision of fitness equipment to schools, enhanced school sport sessions, researcher-led seminars, a smartphone application, and parental strategies for reducing screen time. Assessments were conducted at baseline and immediately post intervention (8 months). Psychological well-being was measured using the Flourishing Scale. Motivational regulations (intrinsic, identified, introjected, controlled, and amotivation) and basic psychological needs (autonomy, competence, and relatedness) in school sport, muscular fitness, resistance training skill competency, and recreational screen time were examined as potential mediating mechanisms of the intervention effect. The intervention effect on well-being was small but statistically significant. Within a multiple mediator model, changes in autonomy needs satisfaction, recreational screen time, and muscular fitness significantly mediated the effect of the intervention on psychological well-being. In addition to the physical health benefits, targeted physical activity programs for adolescent boys may have utility for mental health promotion through the mechanisms of increasing autonomy support and muscular fitness and reducing screen time. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  17. Structural identifiability of cyclic graphical models of biological networks with latent variables.

    Science.gov (United States)

    Wang, Yulin; Lu, Na; Miao, Hongyu

    2016-06-13

    Graphical models have long been used to describe biological networks for a variety of important tasks such as the determination of key biological parameters, and the structure of graphical model ultimately determines whether such unknown parameters can be unambiguously obtained from experimental observations (i.e., the identifiability problem). Limited by resources or technical capacities, complex biological networks are usually partially observed in experiment, which thus introduces latent variables into the corresponding graphical models. A number of previous studies have tackled the parameter identifiability problem for graphical models such as linear structural equation models (SEMs) with or without latent variables. However, the limited resolution and efficiency of existing approaches necessarily calls for further development of novel structural identifiability analysis algorithms. An efficient structural identifiability analysis algorithm is developed in this study for a broad range of network structures. The proposed method adopts the Wright's path coefficient method to generate identifiability equations in forms of symbolic polynomials, and then converts these symbolic equations to binary matrices (called identifiability matrix). Several matrix operations are introduced for identifiability matrix reduction with system equivalency maintained. Based on the reduced identifiability matrices, the structural identifiability of each parameter is determined. A number of benchmark models are used to verify the validity of the proposed approach. Finally, the network module for influenza A virus replication is employed as a real example to illustrate the application of the proposed approach in practice. The proposed approach can deal with cyclic networks with latent variables. The key advantage is that it intentionally avoids symbolic computation and is thus highly efficient. Also, this method is capable of determining the identifiability of each single parameter and

  18. Tuning and Test of Fragmentation Models Based on Identified Particles and Precision Event Shape Data

    CERN Document Server

    Abreu, P; Adye, T; Ajinenko, I; Alekseev, G D; Alemany, R; Allport, P P; Almehed, S; Amaldi, Ugo; Amato, S; Andreazza, A; Andrieux, M L; Antilogus, P; Apel, W D; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barate, R; Barbi, M S; Bardin, Dimitri Yuri; Baroncelli, A; Bärring, O; Barrio, J A; Bartl, Walter; Bates, M J; Battaglia, Marco; Baubillier, M; Baudot, J; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Belous, K S; Benvenuti, Alberto C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Billoir, P; Bloch, D; Blume, M; Bolognese, T; Bonesini, M; Bonivento, W; Booth, P S L; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozzo, M; Branchini, P; Brand, K D; Brenke, T; Brenner, R A; Bricman, C; Brown, R C A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschmann, P; Buys, A; Cabrera, S; Caccia, M; Calvi, M; Camacho-Rozas, A J; Camporesi, T; Canale, V; Canepa, M; Cankocak, K; Cao, F; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Chabaud, V; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chen, M; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Cindro, V; Collins, P; Contreras, J L; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Dahl-Jensen, Erik; Dahm, J; D'Almagne, B; Dam, M; Damgaard, G; Dauncey, P D; Davenport, Martyn; Da Silva, W; Defoix, C; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Brabandere, S; De Clercq, C; La Vaissière, C de; De Lotto, B; De Min, A; De Paula, L S; De Saint-Jean, C; Dijkstra, H; Di Ciaccio, Lucia; Di Diodato, A; Djama, F; Dolbeau, J; Dönszelmann, M; Doroba, K; Dracos, M; Drees, J; Drees, K A; Dris, M; Durand, J D; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fassouliotis, D; Feindt, Michael; Ferrer, A; Fichet, S; Filippas-Tassos, A; Firestone, A; Fischer, P A; Föth, H; Fokitis, E; Fontanelli, F; Formenti, F; Franek, B J; Frenkiel, P; Fries, D E C; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gandelman, M; García, C; García, J; Gaspar, C; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gokieli, R; Golob, B; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Graziani, E; Green, C; Grefrath, A; Gris, P; Grosdidier, G; Grzelak, K; Gumenyuk, S A; Gunnarsson, P; Günther, M; Guy, J; Hahn, F; Hahn, S; Hajduk, Z; Hallgren, A; Hamacher, K; Harris, F J; Hedberg, V; Henriques, R P; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Higón, E; Hilke, Hans Jürgen; Hill, T S; Holmgren, S O; Holt, P J; Holthuizen, D J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, L B; Jönsson, P E; Joram, Christian; Juillot, P; Kaiser, M; Kapusta, F; Karafasoulis, K; Karlsson, M; Karvelas, E; Katsanevas, S; Katsoufis, E C; Keränen, R; Khokhlov, Yu A; Khomenko, B A; Khovanskii, N N; King, B J; Kjaer, N J; Klapp, O; Klein, H; Klovning, A; Kluit, P M; Köne, B; Kokkinias, P; Koratzinos, M; Korcyl, K; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Kreuter, C; Kronkvist, I J; Krumshtein, Z; Krupinski, W; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; Laktineh, I; Lamsa, J; Lanceri, L; Lane, D W; Langefeld, P; Lapin, V; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Legan, C K; Leitner, R; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Libby, J; Liko, D; Lindner, R; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; López, J M; Loukas, D; Lutz, P; Lyons, L; Naughton, J M; Maehlum, G; Mahon, J R; Maio, A; Malmgren, T G M; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Masik, J; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; Medbo, J; Merk, M; Meroni, C; Meyer, S; Meyer, W T; Myagkov, A; Michelotto, M; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Morettini, P; Müller, H; Mulders, M; Mundim, L M; Murray, W J; Muryn, B; Myatt, Gerald; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Neumann, W; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nieuwenhuizen, M; Nikolaenko, V; Niss, P; Nomerotski, A; Normand, Ainsley; Oberschulte-Beckmann, W; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Österberg, K; Ouraou, A; Paganini, P; Paganoni, M; Pagès, P; Pain, R; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Passeri, A; Pegoraro, M; Peralta, L; Pernegger, H; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Petrovykh, M; Phillips, H T; Piana, G; Pierre, F; Plaszczynski, S; Podobrin, O; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Rames, J; Ratoff, P N; Read, A L; Reale, M; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Renton, P B; Resvanis, L K; Richard, F; Richardson, J; Rídky, J; Rinaudo, G; Ripp, I; Romero, A; Roncagliolo, I; Ronchese, P; Roos, L; Rosenberg, E I; Rosso, E; Roudeau, Patrick; Rovelli, T; Rückstuhl, W; Ruhlmann-Kleider, V; Ruiz, A; Rybicki, K; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sahr, O; Sajot, G; Salt, J; Sánchez, J; Sannino, M; Schimmelpfennig, M; Schneider, H; Schwickerath, U; Schyns, M A E; Sciolla, G; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Seitz, A; Sekulin, R L; Serbelloni, L; Shellard, R C; Siegrist, P; Silvestre, R; Simonetti, S; Simonetto, F; Sissakian, A N; Sitár, B; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sokolov, A; Sosnowski, R; Souza-Santos, D; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stanescu, C; Stapnes, Steinar; Stavitski, I; Stevenson, K; Stichelbaut, F; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tavernet, J P; Chikilev, O G; Thomas, J; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Todorova, S; Toet, D Z; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Trischuk, W; Tristram, G; Trombini, A; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tyndel, M; Tzamarias, S; Überschär, B; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; van Apeldoorn, G W; van Dam, P; Van Eldik, J; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Waldner, F; Weierstall, M; Weilhammer, Peter; Weiser, C; Wetherell, Alan M; Wicke, D; Wickens, J H; Wielers, M; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Woschnagg, K; Yip, K; Yushchenko, O P; Zach, F; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zito, M; Zontar, D; Zucchelli, G C; Zumerle, G

    1996-01-01

    Event shape and charged particle inclusive distributions are measured using 750000 decays of the $Z$ to hadrons from the DELPHI detector at LEP. These precise data allow a decisive confrontation with models of the hadronization process. Improved tunings of the JETSET ARIADNE and HERWIG parton shower models and the JETSET matrix element model are obtained by fitting the models to these DELPHI data as well as to identified particle distributions from all LEP experiments. The description of the data distributions by the models is critically reviewed with special importance attributed to identified particles.

  19. Statistical identifiability and convergence evaluation for nonlinear pharmacokinetic models with particle swarm optimization.

    Science.gov (United States)

    Kim, Seongho; Li, Lang

    2014-02-01

    The statistical identifiability of nonlinear pharmacokinetic (PK) models with the Michaelis-Menten (MM) kinetic equation is considered using a global optimization approach, which is particle swarm optimization (PSO). If a model is statistically non-identifiable, the conventional derivative-based estimation approach is often terminated earlier without converging, due to the singularity. To circumvent this difficulty, we develop a derivative-free global optimization algorithm by combining PSO with a derivative-free local optimization algorithm to improve the rate of convergence of PSO. We further propose an efficient approach to not only checking the convergence of estimation but also detecting the identifiability of nonlinear PK models. PK simulation studies demonstrate that the convergence and identifiability of the PK model can be detected efficiently through the proposed approach. The proposed approach is then applied to clinical PK data along with a two-compartmental model. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Identifying Ghanaian Pre-Service Teachers' Readiness for Computer Use: A Technology Acceptance Model Approach

    Science.gov (United States)

    Gyamfi, Stephen Adu

    2016-01-01

    This study extends the technology acceptance model to identify factors that influence technology acceptance among pre-service teachers in Ghana. Data from 380 usable questionnaires were tested against the research model. Utilising the extended technology acceptance model (TAM) as a research framework, the study found that: pre-service teachers'…

  1. Review: To be or not to be an identifiable model. Is this a relevant question in animal science modelling?

    Science.gov (United States)

    Muñoz-Tamayo, R; Puillet, L; Daniel, J B; Sauvant, D; Martin, O; Taghipoor, M; Blavy, P

    2018-04-01

    What is a good (useful) mathematical model in animal science? For models constructed for prediction purposes, the question of model adequacy (usefulness) has been traditionally tackled by statistical analysis applied to observed experimental data relative to model-predicted variables. However, little attention has been paid to analytic tools that exploit the mathematical properties of the model equations. For example, in the context of model calibration, before attempting a numerical estimation of the model parameters, we might want to know if we have any chance of success in estimating a unique best value of the model parameters from available measurements. This question of uniqueness is referred to as structural identifiability; a mathematical property that is defined on the sole basis of the model structure within a hypothetical ideal experiment determined by a setting of model inputs (stimuli) and observable variables (measurements). Structural identifiability analysis applied to dynamic models described by ordinary differential equations (ODEs) is a common practice in control engineering and system identification. This analysis demands mathematical technicalities that are beyond the academic background of animal science, which might explain the lack of pervasiveness of identifiability analysis in animal science modelling. To fill this gap, in this paper we address the analysis of structural identifiability from a practitioner perspective by capitalizing on the use of dedicated software tools. Our objectives are (i) to provide a comprehensive explanation of the structural identifiability notion for the community of animal science modelling, (ii) to assess the relevance of identifiability analysis in animal science modelling and (iii) to motivate the community to use identifiability analysis in the modelling practice (when the identifiability question is relevant). We focus our study on ODE models. By using illustrative examples that include published

  2. Vulnerable girls and dangerous boys

    DEFF Research Database (Denmark)

    Henriksen, Ann-Karina Eske

    2017-01-01

    , and young people’s experiences of confinement. Drawing on Foucauldian power analytics and post-structuralist feminist theory on subjectivity, the study finds that the disciplining practices are gendered to promote working-class masculinity for boys and normative femininity and (hetero)sexuality for girls......, with minorizing effects on some boys and girls. The study provides unique insights from a gender-integrated context for confined young people and supplements scholarship on the gendered logics that underpin interventions operating within the penal–social work nexus....

  3. Extending existing structural identifiability analysis methods to mixed-effects models.

    Science.gov (United States)

    Janzén, David L I; Jirstrand, Mats; Chappell, Michael J; Evans, Neil D

    2018-01-01

    The concept of structural identifiability for state-space models is expanded to cover mixed-effects state-space models. Two methods applicable for the analytical study of the structural identifiability of mixed-effects models are presented. The two methods are based on previously established techniques for non-mixed-effects models; namely the Taylor series expansion and the input-output form approach. By generating an exhaustive summary, and by assuming an infinite number of subjects, functions of random variables can be derived which in turn determine the distribution of the system's observation function(s). By considering the uniqueness of the analytical statistical moments of the derived functions of the random variables, the structural identifiability of the corresponding mixed-effects model can be determined. The two methods are applied to a set of examples of mixed-effects models to illustrate how they work in practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Identifying developmental vascular disruptor compounds using a predictive signature and alternative toxicity models

    Science.gov (United States)

    Identifying Developmental Vascular Disruptor Compounds Using a Predictive Signature and Alternative Toxicity Models Presenting Author: Tamara Tal Affiliation: U.S. EPA/ORD/ISTD, RTP, NC, USA Chemically induced vascular toxicity during embryonic development can result in a wide...

  5. Identifying the Goal, User model and Conditions of Recommender Systems for Formal and Informal Learning

    NARCIS (Netherlands)

    Drachsler, Hendrik; Hummel, Hans; Koper, Rob

    2008-01-01

    Drachsler, H., Hummel, H. G. K., & Koper, R. (2009). Identifying the Goal, User model and Conditions of Recommender Systems for Formal and Informal Learning. Journal of Digital Information, 10(2), 4-24.

  6. Parameter sensitivity and identifiability for a biogeochemical model of hypoxia in the northern Gulf of Mexico

    Science.gov (United States)

    Local sensitivity analyses and identifiable parameter subsets were used to describe numerical constraints of a hypoxia model for bottom waters of the northern Gulf of Mexico. The sensitivity of state variables differed considerably with parameter changes, although most variables ...

  7. Using maximum entropy modeling to identify and prioritize red spruce forest habitat in West Virginia

    Science.gov (United States)

    Nathan R. Beane; James S. Rentch; Thomas M. Schuler

    2013-01-01

    Red spruce forests in West Virginia are found in island-like distributions at high elevations and provide essential habitat for the endangered Cheat Mountain salamander and the recently delisted Virginia northern flying squirrel. Therefore, it is important to identify restoration priorities of red spruce forests. Maximum entropy modeling was used to identify areas of...

  8. Developing a Model for Identifying Students at Risk of Failure in a First Year Accounting Unit

    Science.gov (United States)

    Smith, Malcolm; Therry, Len; Whale, Jacqui

    2012-01-01

    This paper reports on the process involved in attempting to build a predictive model capable of identifying students at risk of failure in a first year accounting unit in an Australian university. Identifying attributes that contribute to students being at risk can lead to the development of appropriate intervention strategies and support…

  9. Dynamical compensation and structural identifiability of biological models: Analysis, implications, and reconciliation.

    Science.gov (United States)

    Villaverde, Alejandro F; Banga, Julio R

    2017-11-01

    The concept of dynamical compensation has been recently introduced to describe the ability of a biological system to keep its output dynamics unchanged in the face of varying parameters. However, the original definition of dynamical compensation amounts to lack of structural identifiability. This is relevant if model parameters need to be estimated, as is often the case in biological modelling. Care should we taken when using an unidentifiable model to extract biological insight: the estimated values of structurally unidentifiable parameters are meaningless, and model predictions about unmeasured state variables can be wrong. Taking this into account, we explore alternative definitions of dynamical compensation that do not necessarily imply structural unidentifiability. Accordingly, we show different ways in which a model can be made identifiable while exhibiting dynamical compensation. Our analyses enable the use of the new concept of dynamical compensation in the context of parameter identification, and reconcile it with the desirable property of structural identifiability.

  10. A Numerical Procedure for Model Identifiability Analysis Applied to Enzyme Kinetics

    DEFF Research Database (Denmark)

    Daele, Timothy, Van; Van Hoey, Stijn; Gernaey, Krist

    2015-01-01

    The proper calibration of models describing enzyme kinetics can be quite challenging. In the literature, different procedures are available to calibrate these enzymatic models in an efficient way. However, in most cases the model structure is already decided on prior to the actual calibration...... and Pronzato (1997) and which can be easily set up for any type of model. In this paper the proposed approach is applied to the forward reaction rate of the enzyme kinetics proposed by Shin and Kim(1998). Structural identifiability analysis showed that no local structural model problems were occurring......) identifiability problems. By using the presented approach it is possible to detect potential identifiability problems and avoid pointless calibration (and experimental!) effort....

  11. A boy with bilateral SUNA

    DEFF Research Database (Denmark)

    Vuković Cvetković, Vlasta; Jensen, Rigmor Højland

    2017-01-01

    secondary causes should be searched for vigorously if there are bilateral symptoms. Despite a number of therapeutic trials, effective management for the majority of SUNA patients is not available at present. Management of SUNA is often difficult. Case We report the case of a young boy with bilateral SUNA...

  12. How Schools Discriminate against Boys.

    Science.gov (United States)

    McGuinness, Diane

    1979-01-01

    Biological differences between the sexes in motor, sensory, and some intellectual abilities are reviewed. The skills that lead to early success in school draw on female talents; as a result, boys are often labeled hyperactive. Journal availability: Human Nature, Inc., Subscriptions Department, P.O. Box 10702, Des Moines, Iowa 50340; single copy…

  13. Why I Teach "Black Boy."

    Science.gov (United States)

    Mahle, Benjamin

    1983-01-01

    Argues that Richard Wright's "Black Boy" is appropriate for ninth-grade students because it combines an exciting story of survival with effective prose, forces readers to try to understand their own experiences in the light of the protagonist's, and intimately involves students in such universal concerns as suffering, violence, and…

  14. A Systematic Approach to Determining the Identifiability of Multistage Carcinogenesis Models.

    Science.gov (United States)

    Brouwer, Andrew F; Meza, Rafael; Eisenberg, Marisa C

    2017-07-01

    Multistage clonal expansion (MSCE) models of carcinogenesis are continuous-time Markov process models often used to relate cancer incidence to biological mechanism. Identifiability analysis determines what model parameter combinations can, theoretically, be estimated from given data. We use a systematic approach, based on differential algebra methods traditionally used for deterministic ordinary differential equation (ODE) models, to determine identifiable combinations for a generalized subclass of MSCE models with any number of preinitation stages and one clonal expansion. Additionally, we determine the identifiable combinations of the generalized MSCE model with up to four clonal expansion stages, and conjecture the results for any number of clonal expansion stages. The results improve upon previous work in a number of ways and provide a framework to find the identifiable combinations for further variations on the MSCE models. Finally, our approach, which takes advantage of the Kolmogorov backward equations for the probability generating functions of the Markov process, demonstrates that identifiability methods used in engineering and mathematics for systems of ODEs can be applied to continuous-time Markov processes. © 2016 Society for Risk Analysis.

  15. Robust global identifiability theory using potentials--Application to compartmental models.

    Science.gov (United States)

    Wongvanich, N; Hann, C E; Sirisena, H R

    2015-04-01

    This paper presents a global practical identifiability theory for analyzing and identifying linear and nonlinear compartmental models. The compartmental system is prolonged onto the potential jet space to formulate a set of input-output equations that are integrals in terms of the measured data, which allows for robust identification of parameters without requiring any simulation of the model differential equations. Two classes of linear and non-linear compartmental models are considered. The theory is first applied to analyze the linear nitrous oxide (N2O) uptake model. The fitting accuracy of the identified models from differential jet space and potential jet space identifiability theories is compared with a realistic noise level of 3% which is derived from sensor noise data in the literature. The potential jet space approach gave a match that was well within the coefficient of variation. The differential jet space formulation was unstable and not suitable for parameter identification. The proposed theory is then applied to a nonlinear immunological model for mastitis in cows. In addition, the model formulation is extended to include an iterative method which allows initial conditions to be accurately identified. With up to 10% noise, the potential jet space theory predicts the normalized population concentration infected with pathogens, to within 9% of the true curve. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Examples of testing global identifiability of biological and biomedical models with the DAISY software.

    Science.gov (United States)

    Saccomani, Maria Pia; Audoly, Stefania; Bellu, Giuseppina; D'Angiò, Leontina

    2010-04-01

    DAISY (Differential Algebra for Identifiability of SYstems) is a recently developed computer algebra software tool which can be used to automatically check global identifiability of (linear and) nonlinear dynamic models described by differential equations involving polynomial or rational functions. Global identifiability is a fundamental prerequisite for model identification which is important not only for biological or medical systems but also for many physical and engineering systems derived from first principles. Lack of identifiability implies that the parameter estimation techniques may not fail but any obtained numerical estimates will be meaningless. The software does not require understanding of the underlying mathematical principles and can be used by researchers in applied fields with a minimum of mathematical background. We illustrate the DAISY software by checking the a priori global identifiability of two benchmark nonlinear models taken from the literature. The analysis of these two examples includes comparison with other methods and demonstrates how identifiability analysis is simplified by this tool. Thus we illustrate the identifiability analysis of other two examples, by including discussion of some specific aspects related to the role of observability and knowledge of initial conditions in testing identifiability and to the computational complexity of the software. The main focus of this paper is not on the description of the mathematical background of the algorithm, which has been presented elsewhere, but on illustrating its use and on some of its more interesting features. DAISY is available on the web site http://www.dei.unipd.it/ approximately pia/. 2010 Elsevier Ltd. All rights reserved.

  17. The Baby TALK Model: An Innovative Approach to Identifying High-Risk Children and Families

    Science.gov (United States)

    Villalpando, Aimee Hilado; Leow, Christine; Hornstein, John

    2012-01-01

    This research report examines the Baby TALK model, an innovative early childhood intervention approach used to identify, recruit, and serve young children who are at-risk for developmental delays, mental health needs, and/or school failure, and their families. The report begins with a description of the model. This description is followed by an…

  18. Modeling Success: Using Preenrollment Data to Identify Academically At-Risk Students

    Science.gov (United States)

    Gansemer-Topf, Ann M.; Compton, Jonathan; Wohlgemuth, Darin; Forbes, Greg; Ralston, Ekaterina

    2015-01-01

    Improving student success and degree completion is one of the core principles of strategic enrollment management. To address this principle, institutional data were used to develop a statistical model to identify academically at-risk students. The model employs multiple linear regression techniques to predict students at risk of earning below a…

  19. Identifying Multiple Levels of Discussion-Based Teaching Strategies for Constructing Scientific Models

    Science.gov (United States)

    Williams, Grant; Clement, John

    2015-01-01

    This study sought to identify specific types of discussion-based strategies that two successful high school physics teachers using a model-based approach utilized in attempting to foster students' construction of explanatory models for scientific concepts. We found evidence that, in addition to previously documented dialogical strategies that…

  20. THE BULLYING PHENOMENON: DIFFERENCES BETWEEN BOYS AND GIRLS

    Directory of Open Access Journals (Sweden)

    Fernanda Silva

    2016-04-01

    Full Text Available The bullying phenomenon is characterized by aggression always unequal power and involves violence. This study aimed to identify the types of bullying (physical, verbal, psychological, material, virtual or sexual more prevalent in this population and compare bullying among adolescent males and females. We used a questionnaire prepared by the researcher. Participants were 309 students, 142 males and 167 females, from 6th to 8th grade from two schools, one state and one municipal. These results show 27% of participants were involved in episodes of bullying and that the most prevalent type of bullying was verbal, being appointed for 92% of girls and 84% boys; followed by psychological, indicated by 70% of girls and 53% boys. Physical bullying, had 46% of female and 44% male reports, the material was mentioned by 27% of girls and 16% boys. On sexual bullying type was greatest difference between the sexes, suffered by 38% of girls and 16% boys. Only 13% of girls and 12% boys, mentioned suffer the virtual bullying. Corroborating research area, in this study the highest percentage of victims were female and different from the literature girls reported being verbally abused more for boys than for girls.

  1. Simultaneous Parameters Identifiability and Estimation of an E. coli Metabolic Network Model

    Directory of Open Access Journals (Sweden)

    Kese Pontes Freitas Alberton

    2015-01-01

    Full Text Available This work proposes a procedure for simultaneous parameters identifiability and estimation in metabolic networks in order to overcome difficulties associated with lack of experimental data and large number of parameters, a common scenario in the modeling of such systems. As case study, the complex real problem of parameters identifiability of the Escherichia coli K-12 W3110 dynamic model was investigated, composed by 18 differential ordinary equations and 35 kinetic rates, containing 125 parameters. With the procedure, model fit was improved for most of the measured metabolites, achieving 58 parameters estimated, including 5 unknown initial conditions. The results indicate that simultaneous parameters identifiability and estimation approach in metabolic networks is appealing, since model fit to the most of measured metabolites was possible even when important measures of intracellular metabolites and good initial estimates of parameters are not available.

  2. Identifiability of tree-child phylogenetic networks under a probabilistic recombination-mutation model of evolution.

    Science.gov (United States)

    Francis, Andrew; Moulton, Vincent

    2018-06-07

    Phylogenetic networks are an extension of phylogenetic trees which are used to represent evolutionary histories in which reticulation events (such as recombination and hybridization) have occurred. A central question for such networks is that of identifiability, which essentially asks under what circumstances can we reliably identify the phylogenetic network that gave rise to the observed data? Recently, identifiability results have appeared for networks relative to a model of sequence evolution that generalizes the standard Markov models used for phylogenetic trees. However, these results are quite limited in terms of the complexity of the networks that are considered. In this paper, by introducing an alternative probabilistic model for evolution along a network that is based on some ground-breaking work by Thatte for pedigrees, we are able to obtain an identifiability result for a much larger class of phylogenetic networks (essentially the class of so-called tree-child networks). To prove our main theorem, we derive some new results for identifying tree-child networks combinatorially, and then adapt some techniques developed by Thatte for pedigrees to show that our combinatorial results imply identifiability in the probabilistic setting. We hope that the introduction of our new model for networks could lead to new approaches to reliably construct phylogenetic networks. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Vertebrae classification models - Validating classification models that use morphometrics to identify ancient salmonid (Oncorhynchus spp.) vertebrae to species

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Using morphometric characteristics of modern salmonid (Oncorhynchus spp.) vertebrae, we have developed classification models to identify salmonid vertebrae to the...

  4. A Bayesian approach to identifying and compensating for model misspecification in population models.

    Science.gov (United States)

    Thorson, James T; Ono, Kotaro; Munch, Stephan B

    2014-02-01

    State-space estimation methods are increasingly used in ecology to estimate productivity and abundance of natural populations while accounting for variability in both population dynamics and measurement processes. However, functional forms for population dynamics and density dependence often will not match the true biological process, and this may degrade the performance of state-space methods. We therefore developed a Bayesian semiparametric state-space model, which uses a Gaussian process (GP) to approximate the population growth function. This offers two benefits for population modeling. First, it allows data to update a specified "prior" on the population growth function, while reverting to this prior when data are uninformative. Second, it allows variability in population dynamics to be decomposed into random errors around the population growth function ("process error") and errors due to the mismatch between the specified prior and estimated growth function ("model error"). We used simulation modeling to illustrate the utility of GP methods in state-space population dynamics models. Results confirmed that the GP model performs similarly to a conventional state-space model when either (1) the prior matches the true process or (2) data are relatively uninformative. However, GP methods improve estimates of the population growth function when the function is misspecified. Results also demonstrated that the estimated magnitude of "model error" can be used to distinguish cases of model misspecification. We conclude with a discussion of the prospects for GP methods in other state-space models, including age and length-structured, meta-analytic, and individual-movement models.

  5. Objective Model Selection for Identifying the Human Feedforward Response in Manual Control.

    Science.gov (United States)

    Drop, Frank M; Pool, Daan M; van Paassen, Marinus Rene M; Mulder, Max; Bulthoff, Heinrich H

    2018-01-01

    Realistic manual control tasks typically involve predictable target signals and random disturbances. The human controller (HC) is hypothesized to use a feedforward control strategy for target-following, in addition to feedback control for disturbance-rejection. Little is known about human feedforward control, partly because common system identification methods have difficulty in identifying whether, and (if so) how, the HC applies a feedforward strategy. In this paper, an identification procedure is presented that aims at an objective model selection for identifying the human feedforward response, using linear time-invariant autoregressive with exogenous input models. A new model selection criterion is proposed to decide on the model order (number of parameters) and the presence of feedforward in addition to feedback. For a range of typical control tasks, it is shown by means of Monte Carlo computer simulations that the classical Bayesian information criterion (BIC) leads to selecting models that contain a feedforward path from data generated by a pure feedback model: "false-positive" feedforward detection. To eliminate these false-positives, the modified BIC includes an additional penalty on model complexity. The appropriate weighting is found through computer simulations with a hypothesized HC model prior to performing a tracking experiment. Experimental human-in-the-loop data will be considered in future work. With appropriate weighting, the method correctly identifies the HC dynamics in a wide range of control tasks, without false-positive results.

  6. Identifying influences on model uncertainty: an application using a forest carbon budget model

    Science.gov (United States)

    James E. Smith; Linda S. Heath

    2001-01-01

    Uncertainty is an important consideration for both developers and users of environmental simulation models. Establishing quantitative estimates of uncertainty for deterministic models can be difficult when the underlying bases for such information are scarce. We demonstrate an application of probabilistic uncertainty analysis that provides for refinements in...

  7. Structural identifiability of systems biology models: a critical comparison of methods.

    Directory of Open Access Journals (Sweden)

    Oana-Teodora Chis

    Full Text Available Analysing the properties of a biological system through in silico experimentation requires a satisfactory mathematical representation of the system including accurate values of the model parameters. Fortunately, modern experimental techniques allow obtaining time-series data of appropriate quality which may then be used to estimate unknown parameters. However, in many cases, a subset of those parameters may not be uniquely estimated, independently of the experimental data available or the numerical techniques used for estimation. This lack of identifiability is related to the structure of the model, i.e. the system dynamics plus the observation function. Despite the interest in knowing a priori whether there is any chance of uniquely estimating all model unknown parameters, the structural identifiability analysis for general non-linear dynamic models is still an open question. There is no method amenable to every model, thus at some point we have to face the selection of one of the possibilities. This work presents a critical comparison of the currently available techniques. To this end, we perform the structural identifiability analysis of a collection of biological models. The results reveal that the generating series approach, in combination with identifiability tableaus, offers the most advantageous compromise among range of applicability, computational complexity and information provided.

  8. Obesity and bullying: different effects for boys and girls.

    Science.gov (United States)

    Griffiths, L J; Wolke, D; Page, A S; Horwood, J P

    2006-02-01

    To investigate whether weight category (underweight, average weight, overweight, and obese) at age 7.5 predicts bullying involvement at 8.5 years. Models were tested separately for boys and girls to investigate gender differences in association patterns. Prospective cohort study in southwest England. Height and weight were measured in children at age 7.5 (n = 8210). BMI (kg/m2) was used to define underweight, average weight, overweight, and obese children, according to British age and gender specific growth reference data. Overt (n = 7083) and relational (n = 6932) bullying behaviour was assessed in children at age 8.5. After adjustment for parental social class, compared to average weight boys, obese boys were 1.66 (95% CI 1.04 to 2.66) times more likely to be overt bullies and 1.54 (1.12 to 2.13) times more likely to be overt victims. Obese girls were 1.53 (1.09 to 2.15) times more likely to be overt victims compared to average weight girls. Obesity is predictive of bullying involvement for both boys and girls. Preadolescent obese boys and girls are more likely to be victims of bullying because they deviate from appearance ideals. Other obese boys are likely to be bullies, presumably because of their physical dominance in the peer group.

  9. Air quality models and unusually large ozone increases: Identifying model failures, understanding environmental causes, and improving modeled chemistry

    Science.gov (United States)

    Couzo, Evan A.

    Several factors combine to make ozone (O3) pollution in Houston, Texas, unique when compared to other metropolitan areas. These include complex meteorology, intense clustering of industrial activity, and significant precursor emissions from the heavily urbanized eight-county area. Decades of air pollution research have borne out two different causes, or conceptual models, of O 3 formation. One conceptual model describes a gradual region-wide increase in O3 concentrations "typical" of many large U.S. cities. The other conceptual model links episodic emissions of volatile organic compounds to spatially limited plumes of high O3, which lead to large hourly increases that have exceeded 100 parts per billion (ppb) per hour. These large hourly increases are known to lead to violations of the federal O 3 standard and impact Houston's status as a non-attainment area. There is a need to further understand and characterize the causes of peak O 3 levels in Houston and simulate them correctly so that environmental regulators can find the most cost-effective pollution controls. This work provides a detailed understanding of unusually large O 3 increases in the natural and modeled environments. First, we probe regulatory model simulations and assess their ability to reproduce the observed phenomenon. As configured for the purpose of demonstrating future attainment of the O3 standard, the model fails to predict the spatially limited O3 plumes observed in Houston. Second, we combine ambient meteorological and pollutant measurement data to identify the most likely geographic origins and preconditions of the concentrated O3 plumes. We find evidence that the O3 plumes are the result of photochemical activity accelerated by industrial emissions. And, third, we implement changes to the modeled chemistry to add missing formation mechanisms of nitrous acid, which is an important radical precursor. Radicals control the chemical reactivity of atmospheric systems, and perturbations to

  10. A Conceptual Model to Identify Intent to Use Chemical-Biological Weapons

    Directory of Open Access Journals (Sweden)

    Mary Zalesny

    2017-10-01

    Full Text Available This paper describes a conceptual model to identify and interrelate indicators of intent of non-state actors to use chemical or biological weapons. The model expands on earlier efforts to understand intent to use weapons of mass destruction by building upon well-researched theories of intent and behavior and focusing on a sub-set of weapons of mass destruction (WMD to account for the distinct challenges of employing different types of WMD in violent acts. The conceptual model is presented as a first, critical step in developing a computational model for assessing the potential for groups to use chemical or biological weapons.

  11. Identified state-space prediction model for aero-optical wavefronts

    Science.gov (United States)

    Faghihi, Azin; Tesch, Jonathan; Gibson, Steve

    2013-07-01

    A state-space disturbance model and associated prediction filter for aero-optical wavefronts are described. The model is computed by system identification from a sequence of wavefronts measured in an airborne laboratory. Estimates of the statistics and flow velocity of the wavefront data are shown and can be computed from the matrices in the state-space model without returning to the original data. Numerical results compare velocity values and power spectra computed from the identified state-space model with those computed from the aero-optical data.

  12. Identifying best-fitting inputs in health-economic model calibration: a Pareto frontier approach.

    Science.gov (United States)

    Enns, Eva A; Cipriano, Lauren E; Simons, Cyrena T; Kong, Chung Yin

    2015-02-01

    To identify best-fitting input sets using model calibration, individual calibration target fits are often combined into a single goodness-of-fit (GOF) measure using a set of weights. Decisions in the calibration process, such as which weights to use, influence which sets of model inputs are identified as best-fitting, potentially leading to different health economic conclusions. We present an alternative approach to identifying best-fitting input sets based on the concept of Pareto-optimality. A set of model inputs is on the Pareto frontier if no other input set simultaneously fits all calibration targets as well or better. We demonstrate the Pareto frontier approach in the calibration of 2 models: a simple, illustrative Markov model and a previously published cost-effectiveness model of transcatheter aortic valve replacement (TAVR). For each model, we compare the input sets on the Pareto frontier to an equal number of best-fitting input sets according to 2 possible weighted-sum GOF scoring systems, and we compare the health economic conclusions arising from these different definitions of best-fitting. For the simple model, outcomes evaluated over the best-fitting input sets according to the 2 weighted-sum GOF schemes were virtually nonoverlapping on the cost-effectiveness plane and resulted in very different incremental cost-effectiveness ratios ($79,300 [95% CI 72,500-87,600] v. $139,700 [95% CI 79,900-182,800] per quality-adjusted life-year [QALY] gained). Input sets on the Pareto frontier spanned both regions ($79,000 [95% CI 64,900-156,200] per QALY gained). The TAVR model yielded similar results. Choices in generating a summary GOF score may result in different health economic conclusions. The Pareto frontier approach eliminates the need to make these choices by using an intuitive and transparent notion of optimality as the basis for identifying best-fitting input sets. © The Author(s) 2014.

  13. Improving the precision of lake ecosystem metabolism estimates by identifying predictors of model uncertainty

    Science.gov (United States)

    Rose, Kevin C.; Winslow, Luke A.; Read, Jordan S.; Read, Emily K.; Solomon, Christopher T.; Adrian, Rita; Hanson, Paul C.

    2014-01-01

    Diel changes in dissolved oxygen are often used to estimate gross primary production (GPP) and ecosystem respiration (ER) in aquatic ecosystems. Despite the widespread use of this approach to understand ecosystem metabolism, we are only beginning to understand the degree and underlying causes of uncertainty for metabolism model parameter estimates. Here, we present a novel approach to improve the precision and accuracy of ecosystem metabolism estimates by identifying physical metrics that indicate when metabolism estimates are highly uncertain. Using datasets from seventeen instrumented GLEON (Global Lake Ecological Observatory Network) lakes, we discovered that many physical characteristics correlated with uncertainty, including PAR (photosynthetically active radiation, 400-700 nm), daily variance in Schmidt stability, and wind speed. Low PAR was a consistent predictor of high variance in GPP model parameters, but also corresponded with low ER model parameter variance. We identified a threshold (30% of clear sky PAR) below which GPP parameter variance increased rapidly and was significantly greater in nearly all lakes compared with variance on days with PAR levels above this threshold. The relationship between daily variance in Schmidt stability and GPP model parameter variance depended on trophic status, whereas daily variance in Schmidt stability was consistently positively related to ER model parameter variance. Wind speeds in the range of ~0.8-3 m s–1 were consistent predictors of high variance for both GPP and ER model parameters, with greater uncertainty in eutrophic lakes. Our findings can be used to reduce ecosystem metabolism model parameter uncertainty and identify potential sources of that uncertainty.

  14. A new approach to hazardous materials transportation risk analysis: decision modeling to identify critical variables.

    Science.gov (United States)

    Clark, Renee M; Besterfield-Sacre, Mary E

    2009-03-01

    We take a novel approach to analyzing hazardous materials transportation risk in this research. Previous studies analyzed this risk from an operations research (OR) or quantitative risk assessment (QRA) perspective by minimizing or calculating risk along a transport route. Further, even though the majority of incidents occur when containers are unloaded, the research has not focused on transportation-related activities, including container loading and unloading. In this work, we developed a decision model of a hazardous materials release during unloading using actual data and an exploratory data modeling approach. Previous studies have had a theoretical perspective in terms of identifying and advancing the key variables related to this risk, and there has not been a focus on probability and statistics-based approaches for doing this. Our decision model empirically identifies the critical variables using an exploratory methodology for a large, highly categorical database involving latent class analysis (LCA), loglinear modeling, and Bayesian networking. Our model identified the most influential variables and countermeasures for two consequences of a hazmat incident, dollar loss and release quantity, and is one of the first models to do this. The most influential variables were found to be related to the failure of the container. In addition to analyzing hazmat risk, our methodology can be used to develop data-driven models for strategic decision making in other domains involving risk.

  15. Achievement in Boys' Schools 2010-12

    Science.gov (United States)

    Wylie, Cathy; Berg, Melanie

    2014-01-01

    This report explores the achievement of school leavers from state and state-integrated boys' schools. The analysis from 2010 to 2012 shows school leavers from state boys' schools had higher qualifications than their male counterparts who attended state co-educational schools. The research was carried out for the Association of Boys' Schools of New…

  16. Relationships Play Primary Role in Boys' Learning

    Science.gov (United States)

    Reichert. Michael; Hawley. Richard

    2013-01-01

    There is a pantheon of literature and popular panic pointing toward the academic ascent of girls and the decline of boys. On the contrary, the reality is different: Boys are learning and succeeding in many places. Two studies find that the places where boys excel have several common characteristics, including teachers who relate to the boys…

  17. Data Mining and Pattern Recognition Models for Identifying Inherited Diseases: Challenges and Implications

    OpenAIRE

    Iddamalgoda, Lahiru; Das, Partha S.; Aponso, Achala; Sundararajan, Vijayaraghava S.; Suravajhala, Prashanth; Valadi, Jayaraman K.

    2016-01-01

    Data mining and pattern recognition methods reveal interesting findings in genetic studies, especially on how the genetic makeup is associated with inherited diseases. Although researchers have proposed various data mining models for biomedical approaches, there remains a challenge in accurately prioritizing the single nucleotide polymorphisms (SNP) associated with the disease. In this commentary, we review the state-of-art data mining and pattern recognition models for identifying inherited ...

  18. Comparison of two model approaches in the Zambezi river basin with regard to model reliability and identifiability

    Directory of Open Access Journals (Sweden)

    H. C. Winsemius

    2006-01-01

    Full Text Available Variations of water stocks in the upper Zambezi river basin have been determined by 2 different hydrological modelling approaches. The purpose was to provide preliminary terrestrial storage estimates in the upper Zambezi, which will be compared with estimates derived from the Gravity Recovery And Climate Experiment (GRACE in a future study. The first modelling approach is GIS-based, distributed and conceptual (STREAM. The second approach uses Lumped Elementary Watersheds identified and modelled conceptually (LEW. The STREAM model structure has been assessed using GLUE (Generalized Likelihood Uncertainty Estimation a posteriori to determine parameter identifiability. The LEW approach could, in addition, be tested for model structure, because computational efforts of LEW are low. Both models are threshold models, where the non-linear behaviour of the Zambezi river basin is explained by a combination of thresholds and linear reservoirs. The models were forced by time series of gauged and interpolated rainfall. Where available, runoff station data was used to calibrate the models. Ungauged watersheds were generally given the same parameter sets as their neighbouring calibrated watersheds. It appeared that the LEW model structure could be improved by applying GLUE iteratively. Eventually, it led to better identifiability of parameters and consequently a better model structure than the STREAM model. Hence, the final model structure obtained better represents the true hydrology. After calibration, both models show a comparable efficiency in representing discharge. However the LEW model shows a far greater storage amplitude than the STREAM model. This emphasizes the storage uncertainty related to hydrological modelling in data-scarce environments such as the Zambezi river basin. It underlines the need and potential for independent observations of terrestrial storage to enhance our understanding and modelling capacity of the hydrological processes. GRACE

  19. Optimal input shaping for Fisher identifiability of control-oriented lithium-ion battery models

    Science.gov (United States)

    Rothenberger, Michael J.

    This dissertation examines the fundamental challenge of optimally shaping input trajectories to maximize parameter identifiability of control-oriented lithium-ion battery models. Identifiability is a property from information theory that determines the solvability of parameter estimation for mathematical models using input-output measurements. This dissertation creates a framework that exploits the Fisher information metric to quantify the level of battery parameter identifiability, optimizes this metric through input shaping, and facilitates faster and more accurate estimation. The popularity of lithium-ion batteries is growing significantly in the energy storage domain, especially for stationary and transportation applications. While these cells have excellent power and energy densities, they are plagued with safety and lifespan concerns. These concerns are often resolved in the industry through conservative current and voltage operating limits, which reduce the overall performance and still lack robustness in detecting catastrophic failure modes. New advances in automotive battery management systems mitigate these challenges through the incorporation of model-based control to increase performance, safety, and lifespan. To achieve these goals, model-based control requires accurate parameterization of the battery model. While many groups in the literature study a variety of methods to perform battery parameter estimation, a fundamental issue of poor parameter identifiability remains apparent for lithium-ion battery models. This fundamental challenge of battery identifiability is studied extensively in the literature, and some groups are even approaching the problem of improving the ability to estimate the model parameters. The first approach is to add additional sensors to the battery to gain more information that is used for estimation. The other main approach is to shape the input trajectories to increase the amount of information that can be gained from input

  20. Inference in partially identified models with many moment inequalities using Lasso

    DEFF Research Database (Denmark)

    Bugni, Federico A.; Caner, Mehmet; Kock, Anders Bredahl

    This paper considers the problem of inference in a partially identified moment (in)equality model with possibly many moment inequalities. Our contribution is to propose a novel two-step new inference method based on the combination of two ideas. On the one hand, our test statistic and critical...

  1. Using neutral models to identify constraints on low-severity fire regimes.

    Science.gov (United States)

    Donald McKenzie; Amy E. Hessl; Lara-Karena B. Kellogg

    2006-01-01

    Climate, topography, fuel loadings, and human activities all affect spatial and temporal patterns of fire occurrence. Because fire is modeled as a stochastic process, for which each fire history is only one realization, a simulation approach is necessary to understand baseline variability, thereby identifying constraints, or forcing functions, that affect fire regimes...

  2. Using Predictive Modelling to Identify Students at Risk of Poor University Outcomes

    Science.gov (United States)

    Jia, Pengfei; Maloney, Tim

    2015-01-01

    Predictive modelling is used to identify students at risk of failing their first-year courses and not returning to university in the second year. Our aim is twofold. Firstly, we want to understand the factors that lead to poor first-year experiences at university. Secondly, we want to develop simple, low-cost tools that would allow universities to…

  3. Identifying biological concepts from a protein-related corpus with a probabilistic topic model

    Directory of Open Access Journals (Sweden)

    Lu Xinghua

    2006-02-01

    Full Text Available Abstract Background Biomedical literature, e.g., MEDLINE, contains a wealth of knowledge regarding functions of proteins. Major recurring biological concepts within such text corpora represent the domains of this body of knowledge. The goal of this research is to identify the major biological topics/concepts from a corpus of protein-related MEDLINE© titles and abstracts by applying a probabilistic topic model. Results The latent Dirichlet allocation (LDA model was applied to the corpus. Based on the Bayesian model selection, 300 major topics were extracted from the corpus. The majority of identified topics/concepts was found to be semantically coherent and most represented biological objects or concepts. The identified topics/concepts were further mapped to the controlled vocabulary of the Gene Ontology (GO terms based on mutual information. Conclusion The major and recurring biological concepts within a collection of MEDLINE documents can be extracted by the LDA model. The identified topics/concepts provide parsimonious and semantically-enriched representation of the texts in a semantic space with reduced dimensionality and can be used to index text.

  4. Structural identifiability analyses of candidate models for in vitro Pitavastatin hepatic uptake.

    Science.gov (United States)

    Grandjean, Thomas R B; Chappell, Michael J; Yates, James W T; Evans, Neil D

    2014-05-01

    In this paper a review of the application of four different techniques (a version of the similarity transformation approach for autonomous uncontrolled systems, a non-differential input/output observable normal form approach, the characteristic set differential algebra and a recent algebraic input/output relationship approach) to determine the structural identifiability of certain in vitro nonlinear pharmacokinetic models is provided. The Organic Anion Transporting Polypeptide (OATP) substrate, Pitavastatin, is used as a probe on freshly isolated animal and human hepatocytes. Candidate pharmacokinetic non-linear compartmental models have been derived to characterise the uptake process of Pitavastatin. As a prerequisite to parameter estimation, structural identifiability analyses are performed to establish that all unknown parameters can be identified from the experimental observations available. Copyright © 2013. Published by Elsevier Ireland Ltd.

  5. Antibiotic Resistances in Livestock: A Comparative Approach to Identify an Appropriate Regression Model for Count Data

    Directory of Open Access Journals (Sweden)

    Anke Hüls

    2017-05-01

    Full Text Available Antimicrobial resistance in livestock is a matter of general concern. To develop hygiene measures and methods for resistance prevention and control, epidemiological studies on a population level are needed to detect factors associated with antimicrobial resistance in livestock holdings. In general, regression models are used to describe these relationships between environmental factors and resistance outcome. Besides the study design, the correlation structures of the different outcomes of antibiotic resistance and structural zero measurements on the resistance outcome as well as on the exposure side are challenges for the epidemiological model building process. The use of appropriate regression models that acknowledge these complexities is essential to assure valid epidemiological interpretations. The aims of this paper are (i to explain the model building process comparing several competing models for count data (negative binomial model, quasi-Poisson model, zero-inflated model, and hurdle model and (ii to compare these models using data from a cross-sectional study on antibiotic resistance in animal husbandry. These goals are essential to evaluate which model is most suitable to identify potential prevention measures. The dataset used as an example in our analyses was generated initially to study the prevalence and associated factors for the appearance of cefotaxime-resistant Escherichia coli in 48 German fattening pig farms. For each farm, the outcome was the count of samples with resistant bacteria. There was almost no overdispersion and only moderate evidence of excess zeros in the data. Our analyses show that it is essential to evaluate regression models in studies analyzing the relationship between environmental factors and antibiotic resistances in livestock. After model comparison based on evaluation of model predictions, Akaike information criterion, and Pearson residuals, here the hurdle model was judged to be the most appropriate

  6. IDENTIFYING OPERATIONAL REQUIREMENTS TO SELECT SUITABLE DECISION MODELS FOR A PUBLIC SECTOR EPROCUREMENT DECISION SUPPORT SYSTEM

    Directory of Open Access Journals (Sweden)

    Mohamed Adil

    2014-10-01

    Full Text Available Public sector procurement should be a transparent and fair process. Strict legal requirements are enforced on public sector procurement to make it a standardised process. To make fair decisions on selecting suppliers, a practical method which adheres to legal requirements is important. The research that is the base for this paper aimed at identifying a suitable Multi-Criteria Decision Analysis (MCDA method for the specific legal and functional needs of the Maldivian Public Sector. To identify such operational requirements, a set of focus group interviews were conducted in the Maldives with public officials responsible for procurement decision making. Based on the operational requirements identified through focus groups, criteria-based evaluation is done on published MCDA methods to identify the suitable methods for e-procurement decision making. This paper describes the identification of the operational requirements and the results of the evaluation to select suitable decision models for the Maldivian context.

  7. Identifying 'unhealthy' food advertising on television: a case study applying the UK Nutrient Profile model.

    Science.gov (United States)

    Jenkin, Gabrielle; Wilson, Nick; Hermanson, Nicole

    2009-05-01

    To evaluate the feasibility of the UK Nutrient Profile (NP) model for identifying 'unhealthy' food advertisements using a case study of New Zealand television advertisements. Four weeks of weekday television from 15.30 hours to 18.30 hours was videotaped from a state-owned (free-to-air) television channel popular with children. Food advertisements were identified and their nutritional information collected in accordance with the requirements of the NP model. Nutrient information was obtained from a variety of sources including food labels, company websites and a national nutritional database. From the 60 h sample of weekday afternoon television, there were 1893 advertisements, of which 483 were for food products or retailers. After applying the NP model, 66 % of these were classified as advertising high-fat, high-salt and high-sugar (HFSS) foods; 28 % were classified as advertising non-HFSS foods; and the remaining 2 % were unclassifiable. More than half (53 %) of the HFSS food advertisements were for 'mixed meal' items promoted by major fast-food franchises. The advertising of non-HFSS food was sparse, covering a narrow range of food groups, with no advertisements for fresh fruit or vegetables. Despite the NP model having some design limitations in classifying real-world televised food advertisements, it was easily applied to this sample and could clearly identify HFSS products. Policy makers who do not wish to completely restrict food advertising to children outright should consider using this NP model for regulating food advertising.

  8. Indistinguishability and identifiability of kinetic models for the MurC reaction in peptidoglycan biosynthesis.

    Science.gov (United States)

    Hattersley, J G; Pérez-Velázquez, J; Chappell, M J; Bearup, D; Roper, D; Dowson, C; Bugg, T; Evans, N D

    2011-11-01

    An important question in Systems Biology is the design of experiments that enable discrimination between two (or more) competing chemical pathway models or biological mechanisms. In this paper analysis is performed between two different models describing the kinetic mechanism of a three-substrate three-product reaction, namely the MurC reaction in the cytoplasmic phase of peptidoglycan biosynthesis. One model involves ordered substrate binding and ordered release of the three products; the competing model also assumes ordered substrate binding, but with fast release of the three products. The two versions are shown to be distinguishable; however, if standard quasi-steady-state assumptions are made distinguishability cannot be determined. Once model structure uniqueness is ensured the experimenter must determine if it is possible to successfully recover rate constant values given the experiment observations, a process known as structural identifiability. Structural identifiability analysis is carried out for both models to determine which of the unknown reaction parameters can be determined uniquely, or otherwise, from the ideal system outputs. This structural analysis forms an integrated step towards the modelling of the full pathway of the cytoplasmic phase of peptidoglycan biosynthesis. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  9. Using cloud models of heartbeats as the entity identifier to secure mobile devices.

    Science.gov (United States)

    Fu, Donglai; Liu, Yanhua

    2017-01-01

    Mobile devices are extensively used to store more private and often sensitive information. Therefore, it is important to protect them against unauthorised access. Authentication ensures that authorised users can use mobile devices. However, traditional authentication methods, such as numerical or graphic passwords, are vulnerable to passive attacks. For example, an adversary can steal the password by snooping from a shorter distance. To avoid these problems, this study presents a biometric approach that uses cloud models of heartbeats as the entity identifier to secure mobile devices. Here, it is identified that these concepts including cloud model or cloud have nothing to do with cloud computing. The cloud model appearing in the study is the cognitive model. In the proposed method, heartbeats are collected by two ECG electrodes that are connected to one mobile device. The backward normal cloud generator is used to generate ECG standard cloud models characterising the heartbeat template. When a user tries to have access to their mobile device, cloud models regenerated by fresh heartbeats will be compared with ECG standard cloud models to determine if the current user can use this mobile device. This authentication method was evaluated from three aspects including accuracy, authentication time and energy consumption. The proposed method gives 86.04% of true acceptance rate with 2.73% of false acceptance rate. One authentication can be done in 6s, and this processing consumes about 2000 mW of power.

  10. Identifying best existing practice for characterization modeling in life cycle impact assessment

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Goedkoop, Mark; Guinée, Jeroen

    2013-01-01

    Purpose: Life cycle impact assessment (LCIA) is a field of active development. The last decade has seen prolific publication of new impact assessment methods covering many different impact categories and providing characterization factors that often deviate from each other for the same substance...... and impact. The LCA standard ISO 14044 is rather general and unspecific in its requirements and offers little help to the LCA practitioner who needs to make a choice. With the aim to identify the best among existing characterization models and provide recommendations to the LCA practitioner, a study...... was performed for the Joint Research Centre of the European Commission (JRC). Methods Existing LCIA methods were collected and their individual characterization models identified at both midpoint and endpoint levels and supplemented with other environmental models of potential use for LCIA. No new developments...

  11. Identifying western yellow-billed cuckoo breeding habitat with a dual modelling approach

    Science.gov (United States)

    Johnson, Matthew J.; Hatten, James R.; Holmes, Jennifer A.; Shafroth, Patrick B.

    2017-01-01

    The western population of the yellow-billed cuckoo (Coccyzus americanus) was recently listed as threatened under the federal Endangered Species Act. Yellow-billed cuckoo conservation efforts require the identification of features and area requirements associated with high quality, riparian forest habitat at spatial scales that range from nest microhabitat to landscape, as well as lower-suitability areas that can be enhanced or restored. Spatially explicit models inform conservation efforts by increasing ecological understanding of a target species, especially at landscape scales. Previous yellow-billed cuckoo modelling efforts derived plant-community maps from aerial photography, an expensive and oftentimes inconsistent approach. Satellite models can remotely map vegetation features (e.g., vegetation density, heterogeneity in vegetation density or structure) across large areas with near perfect repeatability, but they usually cannot identify plant communities. We used aerial photos and satellite imagery, and a hierarchical spatial scale approach, to identify yellow-billed cuckoo breeding habitat along the Lower Colorado River and its tributaries. Aerial-photo and satellite models identified several key features associated with yellow-billed cuckoo breeding locations: (1) a 4.5 ha core area of dense cottonwood-willow vegetation, (2) a large native, heterogeneously dense forest (72 ha) around the core area, and (3) moderately rough topography. The odds of yellow-billed cuckoo occurrence decreased rapidly as the amount of tamarisk cover increased or when cottonwood-willow vegetation was limited. We achieved model accuracies of 75–80% in the project area the following year after updating the imagery and location data. The two model types had very similar probability maps, largely predicting the same areas as high quality habitat. While each model provided unique information, a dual-modelling approach provided a more complete picture of yellow-billed cuckoo habitat

  12. Identifying and quantifying energy savings on fired plant using low cost modelling techniques

    International Nuclear Information System (INIS)

    Tucker, Robert; Ward, John

    2012-01-01

    Research highlights: → Furnace models based on the zone method for radiation calculation are described. → Validated steady-state and transient models have been developed. → We show how these simple models can identify the best options for saving energy. → High emissivity coatings predicted to give performance enhancement on a fired heater. → Optimal heat recovery strategies on a steel reheating furnace are predicted. -- Abstract: Combustion in fired heaters, boilers and furnaces often accounts for the major energy consumption on industrial processes. Small improvements in efficiency can result in large reductions in energy consumption, CO 2 emissions, and operating costs. This paper will describe some useful low cost modelling techniques based on the zone method to help identify energy saving opportunities on high temperature fuel-fired process plant. The zone method has for many decades, been successfully applied to small batch furnaces through to large steel-reheating furnaces, glass tanks, boilers and fired heaters on petrochemical plant. Zone models can simulate both steady-state furnace operation and more complex transient operation typical of a production environment. These models can be used to predict thermal efficiency and performance, and more importantly, to assist in identifying and predicting energy saving opportunities from such measures as: ·Improving air/fuel ratio and temperature controls. ·Improved insulation. ·Use of oxygen or oxygen enrichment. ·Air preheating via flue gas heat recovery. ·Modification to furnace geometry and hearth loading. There is also increasing interest in the application of refractory coatings for increasing surface radiation in fired plant. All of the techniques can yield savings ranging from a few percent upwards and can deliver rapid financial payback, but their evaluation often requires robust and reliable models in order to increase confidence in making financial investment decisions. This paper gives

  13. Using exploratory regression to identify optimal driving factors for cellular automaton modeling of land use change.

    Science.gov (United States)

    Feng, Yongjiu; Tong, Xiaohua

    2017-09-22

    Defining transition rules is an important issue in cellular automaton (CA)-based land use modeling because these models incorporate highly correlated driving factors. Multicollinearity among correlated driving factors may produce negative effects that must be eliminated from the modeling. Using exploratory regression under pre-defined criteria, we identified all possible combinations of factors from the candidate factors affecting land use change. Three combinations that incorporate five driving factors meeting pre-defined criteria were assessed. With the selected combinations of factors, three logistic regression-based CA models were built to simulate dynamic land use change in Shanghai, China, from 2000 to 2015. For comparative purposes, a CA model with all candidate factors was also applied to simulate the land use change. Simulations using three CA models with multicollinearity eliminated performed better (with accuracy improvements about 3.6%) than the model incorporating all candidate factors. Our results showed that not all candidate factors are necessary for accurate CA modeling and the simulations were not sensitive to changes in statistically non-significant driving factors. We conclude that exploratory regression is an effective method to search for the optimal combinations of driving factors, leading to better land use change models that are devoid of multicollinearity. We suggest identification of dominant factors and elimination of multicollinearity before building land change models, making it possible to simulate more realistic outcomes.

  14. Genome-Wide Expression Profiling of Five Mouse Models Identifies Similarities and Differences with Human Psoriasis

    Science.gov (United States)

    Swindell, William R.; Johnston, Andrew; Carbajal, Steve; Han, Gangwen; Wohn, Christian; Lu, Jun; Xing, Xianying; Nair, Rajan P.; Voorhees, John J.; Elder, James T.; Wang, Xiao-Jing; Sano, Shigetoshi; Prens, Errol P.; DiGiovanni, John; Pittelkow, Mark R.; Ward, Nicole L.; Gudjonsson, Johann E.

    2011-01-01

    Development of a suitable mouse model would facilitate the investigation of pathomechanisms underlying human psoriasis and would also assist in development of therapeutic treatments. However, while many psoriasis mouse models have been proposed, no single model recapitulates all features of the human disease, and standardized validation criteria for psoriasis mouse models have not been widely applied. In this study, whole-genome transcriptional profiling is used to compare gene expression patterns manifested by human psoriatic skin lesions with those that occur in five psoriasis mouse models (K5-Tie2, imiquimod, K14-AREG, K5-Stat3C and K5-TGFbeta1). While the cutaneous gene expression profiles associated with each mouse phenotype exhibited statistically significant similarity to the expression profile of psoriasis in humans, each model displayed distinctive sets of similarities and differences in comparison to human psoriasis. For all five models, correspondence to the human disease was strong with respect to genes involved in epidermal development and keratinization. Immune and inflammation-associated gene expression, in contrast, was more variable between models as compared to the human disease. These findings support the value of all five models as research tools, each with identifiable areas of convergence to and divergence from the human disease. Additionally, the approach used in this paper provides an objective and quantitative method for evaluation of proposed mouse models of psoriasis, which can be strategically applied in future studies to score strengths of mouse phenotypes relative to specific aspects of human psoriasis. PMID:21483750

  15. Poor Facial Affect Recognition among Boys with Duchenne Muscular Dystrophy

    Science.gov (United States)

    Hinton, V. J.; Fee, R. J.; De Vivo, D. C.; Goldstein, E.

    2007-01-01

    Children with Duchenne or Becker muscular dystrophy (MD) have delayed language and poor social skills and some meet criteria for Pervasive Developmental Disorder, yet they are identified by molecular, rather than behavioral, characteristics. To determine whether comprehension of facial affect is compromised in boys with MD, children were given a…

  16. Tumor xenograft modeling identifies an association between TCF4 loss and breast cancer chemoresistance

    Directory of Open Access Journals (Sweden)

    Gorka Ruiz de Garibay

    2018-05-01

    Full Text Available Understanding the mechanisms of cancer therapeutic resistance is fundamental to improving cancer care. There is clear benefit from chemotherapy in different breast cancer settings; however, knowledge of the mutations and genes that mediate resistance is incomplete. In this study, by modeling chemoresistance in patient-derived xenografts (PDXs, we show that adaptation to therapy is genetically complex and identify that loss of transcription factor 4 (TCF4; also known as ITF2 is associated with this process. A triple-negative BRCA1-mutated PDX was used to study the genetics of chemoresistance. The PDX was treated in parallel with four chemotherapies for five iterative cycles. Exome sequencing identified few genes with de novo or enriched mutations in common among the different therapies, whereas many common depleted mutations/genes were observed. Analysis of somatic mutations from The Cancer Genome Atlas (TCGA supported the prognostic relevance of the identified genes. A mutation in TCF4 was found de novo in all treatments, and analysis of drug sensitivity profiles across cancer cell lines supported the link to chemoresistance. Loss of TCF4 conferred chemoresistance in breast cancer cell models, possibly by altering cell cycle regulation. Targeted sequencing in chemoresistant tumors identified an intronic variant of TCF4 that may represent an expression quantitative trait locus associated with relapse outcome in TCGA. Immunohistochemical studies suggest a common loss of nuclear TCF4 expression post-chemotherapy. Together, these results from tumor xenograft modeling depict a link between altered TCF4 expression and breast cancer chemoresistance.

  17. Identifying and Classifying Mobile Business Models Based on Meta-Synthesis Approach

    Directory of Open Access Journals (Sweden)

    Porrandokht Niroomand

    2012-03-01

    Full Text Available The appearance of mobile has provided unique opportunities and fields through the development and creation of businesses and has been able to create the new job opportunities. The current research tries to familiarize entrepreneures who are running the businesses especially in the area of mobile services with business models. These business models can familiarize them for implementing the new ideas and designs since they can enter to business market. Searching in many papers shows that there are no propitiated papers and researches that can identify, categorize and analyze the mobile business models. Consequently, this paper involves innovation. The first part of this paper presents the review about the concepts and theories about the different mobile generations, the mobile commerce and business models. Afterwards, 92 models are compared, interpreted, translated and combined using 33 papers, books based on two different criteria that are expert criterion and kind of product criterion. In the classification of models according to models that are presented by experts, the models are classified based on criteria such as business fields, business partners, the rate of dynamism, the kind of activity, the focus areas, the mobile generations, transparency, the type of operator activities, marketing and advertisements. The models that are classified based on the kind of product have been analyzed and classified at four different areas of mobile commerce including the content production, technology (software and hardware, network and synthetic.

  18. Evaluating predictive models for solar energy growth in the US states and identifying the key drivers

    Science.gov (United States)

    Chakraborty, Joheen; Banerji, Sugata

    2018-03-01

    Driven by a desire to control climate change and reduce the dependence on fossil fuels, governments around the world are increasing the adoption of renewable energy sources. However, among the US states, we observe a wide disparity in renewable penetration. In this study, we have identified and cleaned over a dozen datasets representing solar energy penetration in each US state, and the potentially relevant socioeconomic and other factors that may be driving the growth in solar. We have applied a number of predictive modeling approaches - including machine learning and regression - on these datasets over a 17-year period and evaluated the relative performance of the models. Our goals were: (1) identify the most important factors that are driving the growth in solar, (2) choose the most effective predictive modeling technique for solar growth, and (3) develop a model for predicting next year’s solar growth using this year’s data. We obtained very promising results with random forests (about 90% efficacy) and varying degrees of success with support vector machines and regression techniques (linear, polynomial, ridge). We also identified states with solar growth slower than expected and representing a potential for stronger growth in future.

  19. Methodology for identifying parameters for the TRNSYS model Type 210 - wood pellet stoves and boilers

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Tomas; Fiedler, Frank; Nordlander, Svante

    2006-05-15

    This report describes a method how to perform measurements on boilers and stoves and how to identify parameters from the measurements for the boiler/stove-model TRNSYS Type 210. The model can be used for detailed annual system simulations using TRNSYS. Experience from measurements on three different pellet stoves and four boilers were used to develop this methodology. Recommendations for the set up of measurements are given and the required combustion theory for the data evaluation and data preparation are given. The data evaluation showed that the uncertainties are quite large for the measured flue gas flow rate and for boilers and stoves with high fraction of energy going to the water jacket also the calculated heat rate to the room may have large uncertainties. A methodology for the parameter identification process and identified parameters for two different stoves and three boilers are given. Finally the identified models are compared with measured data showing that the model generally agreed well with measured data during both stationary and dynamic conditions.

  20. EARLY CHILDHOOD PREDICTORS OF LOW-INCOME BOYS' PATHWAYS TO ANTISOCIAL BEHAVIOR IN CHILDHOOD, ADOLESCENCE, AND EARLY ADULTHOOD.

    Science.gov (United States)

    Shaw, Daniel S; Gilliam, Mary

    2017-01-01

    Guided by a bridging model of pathways leading to low-income boys' early starting and persistent trajectories of antisocial behavior, the current article reviews evidence supporting the model from early childhood through early adulthood. Using primarily a cohort of 310 low-income boys of families recruited from Women, Infants, and Children Nutrition Supplement centers in a large metropolitan area followed from infancy to early adulthood and a smaller cohort of boys and girls followed through early childhood, we provide evidence supporting the critical role of parenting, maternal depression, and other proximal family risk factors in early childhood that are prospectively linked to trajectories of parent-reported conduct problems in early and middle childhood, youth-reported antisocial behavior during adolescence and early adulthood, and court-reported violent offending in adolescence. The findings are discussed in terms of the need to identify at-risk boys in early childhood and methods and platforms for engaging families in healthcare settings not previously used to implement preventive mental health services. © 2016 Michigan Association for Infant Mental Health.

  1. The Brilliance of Black Boys: Cultivating School Success in the Early Grades

    Science.gov (United States)

    Wright, Brian L.

    2018-01-01

    This much-needed book will help schools and, by extension, society to better understand and identify the promise, potential, and possibilities of Black boys. Drawing from their wealth of experience in early childhood education, the authors present an asset- and strengths-based view of educating Black boys. This positive approach enables…

  2. Boys as Writers: Perspectives on the Learning and Teaching of Writing in Three Primary Schools

    Science.gov (United States)

    Edwards, Gillian; Jones, Jane

    2018-01-01

    Boys' attitude to writing is widely perceived as an issue in English primary and secondary schools. Prior research has identified a link between negative attitudes to writing and lower achievement and raised the issue of the stereotyping of boys as underachievers in literacy. The study reported here suggests that if we are to understand the…

  3. A Study of Scientometric Methods to Identify Emerging Technologies via Modeling of Milestones

    Energy Technology Data Exchange (ETDEWEB)

    Abercrombie, Robert K [ORNL; Udoeyop, Akaninyene W [ORNL; Schlicher, Bob G [ORNL

    2012-01-01

    This work examines a scientometric model that tracks the emergence of an identified technology from initial discovery (via original scientific and conference literature), through critical discoveries (via original scientific, conference literature and patents), transitioning through Technology Readiness Levels (TRLs) and ultimately on to commercial application. During the period of innovation and technology transfer, the impact of scholarly works, patents and on-line web news sources are identified. As trends develop, currency of citations, collaboration indicators, and on-line news patterns are identified. The combinations of four distinct and separate searchable on-line networked sources (i.e., scholarly publications and citation, patents, news archives, and online mapping networks) are assembled to become one collective network (a dataset for analysis of relations). This established network becomes the basis from which to quickly analyze the temporal flow of activity (searchable events) for the example subject domain we investigated.

  4. Use of model plant hosts to identify Pseudomonas aeruginosa virulence factors

    Science.gov (United States)

    Rahme, Laurence G.; Tan, Man-Wah; Le, Long; Wong, Sandy M.; Tompkins, Ronald G.; Calderwood, Stephen B.; Ausubel, Frederick M.

    1997-01-01

    We used plants as an in vivo pathogenesis model for the identification of virulence factors of the human opportunistic pathogen Pseudomonas aeruginosa. Nine of nine TnphoA mutant derivatives of P. aeruginosa strain UCBPP-PA14 that were identified in a plant leaf assay for less pathogenic mutants also exhibited significantly reduced pathogenicity in a burned mouse pathogenicity model, suggesting that P. aeruginosa utilizes common strategies to infect both hosts. Seven of these nine mutants contain TnphoA insertions in previously unknown genes. These results demonstrate that an alternative nonvertebrate host of a human bacterial pathogen can be used in an in vivo high throughput screen to identify novel bacterial virulence factors involved in mammalian pathogenesis. PMID:9371831

  5. Modelling Creativity: Identifying Key Components through a Corpus-Based Approach.

    Science.gov (United States)

    Jordanous, Anna; Keller, Bill

    2016-01-01

    Creativity is a complex, multi-faceted concept encompassing a variety of related aspects, abilities, properties and behaviours. If we wish to study creativity scientifically, then a tractable and well-articulated model of creativity is required. Such a model would be of great value to researchers investigating the nature of creativity and in particular, those concerned with the evaluation of creative practice. This paper describes a unique approach to developing a suitable model of how creative behaviour emerges that is based on the words people use to describe the concept. Using techniques from the field of statistical natural language processing, we identify a collection of fourteen key components of creativity through an analysis of a corpus of academic papers on the topic. Words are identified which appear significantly often in connection with discussions of the concept. Using a measure of lexical similarity to help cluster these words, a number of distinct themes emerge, which collectively contribute to a comprehensive and multi-perspective model of creativity. The components provide an ontology of creativity: a set of building blocks which can be used to model creative practice in a variety of domains. The components have been employed in two case studies to evaluate the creativity of computational systems and have proven useful in articulating achievements of this work and directions for further research.

  6. Identify High-Quality Protein Structural Models by Enhanced K-Means.

    Science.gov (United States)

    Wu, Hongjie; Li, Haiou; Jiang, Min; Chen, Cheng; Lv, Qiang; Wu, Chuang

    2017-01-01

    Background. One critical issue in protein three-dimensional structure prediction using either ab initio or comparative modeling involves identification of high-quality protein structural models from generated decoys. Currently, clustering algorithms are widely used to identify near-native models; however, their performance is dependent upon different conformational decoys, and, for some algorithms, the accuracy declines when the decoy population increases. Results. Here, we proposed two enhanced K -means clustering algorithms capable of robustly identifying high-quality protein structural models. The first one employs the clustering algorithm SPICKER to determine the initial centroids for basic K -means clustering ( SK -means), whereas the other employs squared distance to optimize the initial centroids ( K -means++). Our results showed that SK -means and K -means++ were more robust as compared with SPICKER alone, detecting 33 (59%) and 42 (75%) of 56 targets, respectively, with template modeling scores better than or equal to those of SPICKER. Conclusions. We observed that the classic K -means algorithm showed a similar performance to that of SPICKER, which is a widely used algorithm for protein-structure identification. Both SK -means and K -means++ demonstrated substantial improvements relative to results from SPICKER and classical K -means.

  7. A computational technique to identify the optimal stiffness matrix for a discrete nuclear fuel assembly model

    International Nuclear Information System (INIS)

    Park, Nam-Gyu; Kim, Kyoung-Joo; Kim, Kyoung-Hong; Suh, Jung-Min

    2013-01-01

    Highlights: ► An identification method of the optimal stiffness matrix for a fuel assembly structure is discussed. ► The least squares optimization method is introduced, and a closed form solution of the problem is derived. ► The method can be expanded to the system with the limited number of modes. ► Identification error due to the perturbed mode shape matrix is analyzed. ► Verification examples show that the proposed procedure leads to a reliable solution. -- Abstract: A reactor core structural model which is used to evaluate the structural integrity of the core contains nuclear fuel assembly models. Since the reactor core consists of many nuclear fuel assemblies, the use of a refined fuel assembly model leads to a considerable amount of computing time for performing nonlinear analyses such as the prediction of seismic induced vibration behaviors. The computational time could be reduced by replacing the detailed fuel assembly model with a simplified model that has fewer degrees of freedom, but the dynamic characteristics of the detailed model must be maintained in the simplified model. Such a model based on an optimal design method is proposed in this paper. That is, when a mass matrix and a mode shape matrix are given, the optimal stiffness matrix of a discrete fuel assembly model can be estimated by applying the least squares minimization method. The verification of the method is completed by comparing test results and simulation results. This paper shows that the simplified model's dynamic behaviors are quite similar to experimental results and that the suggested method is suitable for identifying reliable mathematical model for fuel assemblies

  8. Discriminant analysis method to determine the power of the boys 11-12 year

    Directory of Open Access Journals (Sweden)

    Mirosława Cieślicka

    2016-10-01

    Full Text Available Purpose: To determine the model of power in boys 11-12 years old. Material and methods: To achieve the objectives, the following methods: analysis of scientific literature, statistical methods for analysis of results. The study involved 35 boys 11 year (n = 35 and 32 boys 12 year (n = 32. Results: Analysis of the results shows that the statistical significance of differences in the test results of boys 11 and 12 years there has been research jump from the place of execution and the amount of squats (the amount of execution time (p <0.001, p <0. Conclusions: Structural factors discriminant function suggest that more attention is paid to training of speed and endurance, the more likely to increase the force to prepare the boys. The canonical discriminant function can  be used to assess and forecast the development of motor skills in boys.

  9. Comprehensive analyses of ventricular myocyte models identify targets exhibiting favorable rate dependence.

    Directory of Open Access Journals (Sweden)

    Megan A Cummins

    2014-03-01

    Full Text Available Reverse rate dependence is a problematic property of antiarrhythmic drugs that prolong the cardiac action potential (AP. The prolongation caused by reverse rate dependent agents is greater at slow heart rates, resulting in both reduced arrhythmia suppression at fast rates and increased arrhythmia risk at slow rates. The opposite property, forward rate dependence, would theoretically overcome these parallel problems, yet forward rate dependent (FRD antiarrhythmics remain elusive. Moreover, there is evidence that reverse rate dependence is an intrinsic property of perturbations to the AP. We have addressed the possibility of forward rate dependence by performing a comprehensive analysis of 13 ventricular myocyte models. By simulating populations of myocytes with varying properties and analyzing population results statistically, we simultaneously predicted the rate-dependent effects of changes in multiple model parameters. An average of 40 parameters were tested in each model, and effects on AP duration were assessed at slow (0.2 Hz and fast (2 Hz rates. The analysis identified a variety of FRD ionic current perturbations and generated specific predictions regarding their mechanisms. For instance, an increase in L-type calcium current is FRD when this is accompanied by indirect, rate-dependent changes in slow delayed rectifier potassium current. A comparison of predictions across models identified inward rectifier potassium current and the sodium-potassium pump as the two targets most likely to produce FRD AP prolongation. Finally, a statistical analysis of results from the 13 models demonstrated that models displaying minimal rate-dependent changes in AP shape have little capacity for FRD perturbations, whereas models with large shape changes have considerable FRD potential. This can explain differences between species and between ventricular cell types. Overall, this study provides new insights, both specific and general, into the determinants of

  10. Identifying influential data points in hydrological model calibration and their impact on streamflow predictions

    Science.gov (United States)

    Wright, David; Thyer, Mark; Westra, Seth

    2015-04-01

    Highly influential data points are those that have a disproportionately large impact on model performance, parameters and predictions. However, in current hydrological modelling practice the relative influence of individual data points on hydrological model calibration is not commonly evaluated. This presentation illustrates and evaluates several influence diagnostics tools that hydrological modellers can use to assess the relative influence of data. The feasibility and importance of including influence detection diagnostics as a standard tool in hydrological model calibration is discussed. Two classes of influence diagnostics are evaluated: (1) computationally demanding numerical "case deletion" diagnostics; and (2) computationally efficient analytical diagnostics, based on Cook's distance. These diagnostics are compared against hydrologically orientated diagnostics that describe changes in the model parameters (measured through the Mahalanobis distance), performance (objective function displacement) and predictions (mean and maximum streamflow). These influence diagnostics are applied to two case studies: a stage/discharge rating curve model, and a conceptual rainfall-runoff model (GR4J). Removing a single data point from the calibration resulted in differences to mean flow predictions of up to 6% for the rating curve model, and differences to mean and maximum flow predictions of up to 10% and 17%, respectively, for the hydrological model. When using the Nash-Sutcliffe efficiency in calibration, the computationally cheaper Cook's distance metrics produce similar results to the case-deletion metrics at a fraction of the computational cost. However, Cooks distance is adapted from linear regression with inherit assumptions on the data and is therefore less flexible than case deletion. Influential point detection diagnostics show great potential to improve current hydrological modelling practices by identifying highly influential data points. The findings of this

  11. Identifying mechanisms that structure ecological communities by snapping model parameters to empirically observed tradeoffs.

    Science.gov (United States)

    Thomas Clark, Adam; Lehman, Clarence; Tilman, David

    2018-04-01

    Theory predicts that interspecific tradeoffs are primary determinants of coexistence and community composition. Using information from empirically observed tradeoffs to augment the parametrisation of mechanism-based models should therefore improve model predictions, provided that tradeoffs and mechanisms are chosen correctly. We developed and tested such a model for 35 grassland plant species using monoculture measurements of three species characteristics related to nitrogen uptake and retention, which previous experiments indicate as important at our site. Matching classical theoretical expectations, these characteristics defined a distinct tradeoff surface, and models parameterised with these characteristics closely matched observations from experimental multi-species mixtures. Importantly, predictions improved significantly when we incorporated information from tradeoffs by 'snapping' characteristics to the nearest location on the tradeoff surface, suggesting that the tradeoffs and mechanisms we identify are important determinants of local community structure. This 'snapping' method could therefore constitute a broadly applicable test for identifying influential tradeoffs and mechanisms. © 2018 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  12. Computational modeling identifies key gene regulatory interactions underlying phenobarbital-mediated tumor promotion

    Science.gov (United States)

    Luisier, Raphaëlle; Unterberger, Elif B.; Goodman, Jay I.; Schwarz, Michael; Moggs, Jonathan; Terranova, Rémi; van Nimwegen, Erik

    2014-01-01

    Gene regulatory interactions underlying the early stages of non-genotoxic carcinogenesis are poorly understood. Here, we have identified key candidate regulators of phenobarbital (PB)-mediated mouse liver tumorigenesis, a well-characterized model of non-genotoxic carcinogenesis, by applying a new computational modeling approach to a comprehensive collection of in vivo gene expression studies. We have combined our previously developed motif activity response analysis (MARA), which models gene expression patterns in terms of computationally predicted transcription factor binding sites with singular value decomposition (SVD) of the inferred motif activities, to disentangle the roles that different transcriptional regulators play in specific biological pathways of tumor promotion. Furthermore, transgenic mouse models enabled us to identify which of these regulatory activities was downstream of constitutive androstane receptor and β-catenin signaling, both crucial components of PB-mediated liver tumorigenesis. We propose novel roles for E2F and ZFP161 in PB-mediated hepatocyte proliferation and suggest that PB-mediated suppression of ESR1 activity contributes to the development of a tumor-prone environment. Our study shows that combining MARA with SVD allows for automated identification of independent transcription regulatory programs within a complex in vivo tissue environment and provides novel mechanistic insights into PB-mediated hepatocarcinogenesis. PMID:24464994

  13. Identifying Mechanical Properties of Viscoelastic Materials in Time Domain Using the Fractional Zener Model

    Directory of Open Access Journals (Sweden)

    Ana Paula Delowski Ciniello

    Full Text Available Abstract The present paper aims at presenting a methodology for characterizing viscoelastic materials in time domain, taking into account the fractional Zener constitutive model and the influence of temperature through Williams, Landel, and Ferry’s model. To that effect, a set of points obtained experimentally through uniaxial tensile tests with different constant strain rates is considered. The approach is based on the minimization of the quadratic relative distance between the experimental stress-strain curves and the corresponding ones given by the theoretical model. In order to avoid the local minima in the process of optimization, a hybrid technique based on genetic algorithms and non-linear programming techniques is used. The methodology is applied in the characterization of two different commercial viscoelastic materials. The results indicate that the proposed methodology is effective in identifying thermorheologically simple viscoelastic materials.

  14. A mouse model of alcoholic liver fibrosis-associated acute kidney injury identifies key molecular pathways

    International Nuclear Information System (INIS)

    Furuya, Shinji; Chappell, Grace A.; Iwata, Yasuhiro; Uehara, Takeki; Kato, Yuki; Kono, Hiroshi; Bataller, Ramon; Rusyn, Ivan

    2016-01-01

    Clinical data strongly indicate that acute kidney injury (AKI) is a critical complication in alcoholic hepatitis, an acute-on-chronic form of liver failure in patients with advanced alcoholic fibrosis. Development of targeted therapies for AKI in this setting is hampered by the lack of an animal model. To enable research into molecular drivers and novel therapies for fibrosis- and alcohol-associated AKI, we aimed to combine carbon tetrachloride (CCl 4 )-induced fibrosis with chronic intra-gastric alcohol feeding. Male C57BL/6J mice were administered a low dose of CCl 4 (0.2 ml/kg 2 × week/6 weeks) followed by alcohol intragastrically (up to 25 g/kg/day for 3 weeks) and with continued CCl 4 . We observed that combined treatment with CCl 4 and alcohol resulted in severe liver injury, more pronounced than using each treatment alone. Importantly, severe kidney injury was evident only in the combined treatment group. This mouse model reproduced distinct pathological features consistent with AKI in human alcoholic hepatitis. Transcriptomic analysis of kidneys revealed profound effects in the combined treatment group, with enrichment for damage-associated pathways, such as apoptosis, inflammation, immune-response and hypoxia. Interestingly, Havcr1 and Lcn2, biomarkers of AKI, were markedly up-regulated. Overall, this study established a novel mouse model of fibrosis- and alcohol-associated AKI and identified key mechanistic pathways. - Highlights: • Acute kidney injury (AKI) is a critical complication in alcoholic hepatitis • We developed a novel mouse model of fibrosis- and alcohol-associated AKI • This model reproduces key molecular and pathological features of human AKI • This animal model can help identify new targeted therapies for alcoholic hepatitis

  15. Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Markus; Eichbaum, Kathrin [Department of Ecosystem Analysis, Institute for Environmental Research,ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Kammann, Ulrike [Thünen-Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg (Germany); Hudjetz, Sebastian [Department of Ecosystem Analysis, Institute for Environmental Research,ABBt – Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Cofalla, Catrina [Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Buchinger, Sebastian; Reifferscheid, Georg [Federal Institute of Hydrology (BFG), Department G3: Biochemistry, Ecotoxicology, Am Mainzer Tor 1, 56068 Koblenz (Germany); Schüttrumpf, Holger [Institute of Hydraulic Engineering and Water Resources Management, RWTH Aachen University, Mies-van-der-Rohe-Straße 1, 52056 Aachen (Germany); Preuss, Thomas [Department of Environmental Biology and Chemodynamics, Institute for Environmental Research,ABBt- Aachen Biology and Biotechnology, RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); and others

    2014-07-01

    Highlights: • A PBTK model for trout was coupled with a sediment equilibrium partitioning model. • The influence of physical exercise on pollutant uptake was studies using the model. • Physical exercise during flood events can increase the level of biliary metabolites. • Cardiac output and effective respiratory volume were identified as relevant factors. • These confounding factors need to be considered also for bioconcentration studies. - Abstract: As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24 °C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios.

  16. Applying complexity theory: A primer for identifying and modeling firm anomalies

    Directory of Open Access Journals (Sweden)

    Arch G. Woodside

    2018-01-01

    Full Text Available This essay elaborates on the usefulness of embracing complexity theory, modeling outcomes rather than directionality, and modeling complex rather than simple outcomes in strategic management. Complexity theory includes the tenet that most antecedent conditions are neither sufficient nor necessary for the occurrence of a specific outcome. Identifying a firm by individual antecedents (i.e., non-innovative versus highly innovative, small versus large size in sales or number of employees, or serving local versus international markets provides shallow information in modeling specific outcomes (e.g., high sales growth or high profitability—even if directional analyses (e.g., regression analysis, including structural equation modeling indicates that the independent (main effects of the individual antecedents relate to outcomes directionally—because firm (case anomalies almost always occur to main effects. Examples: a number of highly innovative firms have low sales while others have high sales and a number of non-innovative firms have low sales while others have high sales. Breaking-away from the current dominant logic of directionality testing—null hypotheses statistic testing (NHST—to embrace somewhat precise outcome testing (SPOT is necessary for extracting highly useful information about the causes of anomalies—associations opposite to expected and “statistically significant” main effects. The study of anomalies extends to identifying the occurrences of four-corner strategy outcomes: firms doing well in favorable circumstances, firms doing badly in favorable circumstances, firms doing well in unfavorable circumstances, and firms doing badly in unfavorable circumstances. Models of four-corner strategy outcomes advances strategic management beyond the current dominant logic of directional modeling of single outcomes.

  17. A mouse model of alcoholic liver fibrosis-associated acute kidney injury identifies key molecular pathways

    Energy Technology Data Exchange (ETDEWEB)

    Furuya, Shinji; Chappell, Grace A.; Iwata, Yasuhiro [Department of Veterinary Integrative Biosciences, Texas A& M University, College Station, TX (United States); Uehara, Takeki; Kato, Yuki [Laboratory of Veterinary Pathology, Osaka Prefecture University, Osaka (Japan); Kono, Hiroshi [First Department of Surgery, University of Yamanashi, Yamanashi (Japan); Bataller, Ramon [Division of Gastroenterology & Hepatology, Department of Medicine, University of North Carolina, Chapel Hill, NC (United States); Rusyn, Ivan, E-mail: irusyn@tamu.edu [Department of Veterinary Integrative Biosciences, Texas A& M University, College Station, TX (United States)

    2016-11-01

    Clinical data strongly indicate that acute kidney injury (AKI) is a critical complication in alcoholic hepatitis, an acute-on-chronic form of liver failure in patients with advanced alcoholic fibrosis. Development of targeted therapies for AKI in this setting is hampered by the lack of an animal model. To enable research into molecular drivers and novel therapies for fibrosis- and alcohol-associated AKI, we aimed to combine carbon tetrachloride (CCl{sub 4})-induced fibrosis with chronic intra-gastric alcohol feeding. Male C57BL/6J mice were administered a low dose of CCl{sub 4} (0.2 ml/kg 2 × week/6 weeks) followed by alcohol intragastrically (up to 25 g/kg/day for 3 weeks) and with continued CCl{sub 4}. We observed that combined treatment with CCl{sub 4} and alcohol resulted in severe liver injury, more pronounced than using each treatment alone. Importantly, severe kidney injury was evident only in the combined treatment group. This mouse model reproduced distinct pathological features consistent with AKI in human alcoholic hepatitis. Transcriptomic analysis of kidneys revealed profound effects in the combined treatment group, with enrichment for damage-associated pathways, such as apoptosis, inflammation, immune-response and hypoxia. Interestingly, Havcr1 and Lcn2, biomarkers of AKI, were markedly up-regulated. Overall, this study established a novel mouse model of fibrosis- and alcohol-associated AKI and identified key mechanistic pathways. - Highlights: • Acute kidney injury (AKI) is a critical complication in alcoholic hepatitis • We developed a novel mouse model of fibrosis- and alcohol-associated AKI • This model reproduces key molecular and pathological features of human AKI • This animal model can help identify new targeted therapies for alcoholic hepatitis.

  18. Physiologically-based toxicokinetic models help identifying the key factors affecting contaminant uptake during flood events

    International Nuclear Information System (INIS)

    Brinkmann, Markus; Eichbaum, Kathrin; Kammann, Ulrike; Hudjetz, Sebastian; Cofalla, Catrina; Buchinger, Sebastian; Reifferscheid, Georg; Schüttrumpf, Holger; Preuss, Thomas

    2014-01-01

    Highlights: • A PBTK model for trout was coupled with a sediment equilibrium partitioning model. • The influence of physical exercise on pollutant uptake was studies using the model. • Physical exercise during flood events can increase the level of biliary metabolites. • Cardiac output and effective respiratory volume were identified as relevant factors. • These confounding factors need to be considered also for bioconcentration studies. - Abstract: As a consequence of global climate change, we will be likely facing an increasing frequency and intensity of flood events. Thus, the ecotoxicological relevance of sediment re-suspension is of growing concern. It is vital to understand contaminant uptake from suspended sediments and relate it to effects in aquatic biota. Here we report on a computational study that utilizes a physiologically based toxicokinetic model to predict uptake, metabolism and excretion of sediment-borne pyrene in rainbow trout (Oncorhynchus mykiss). To this end, data from two experimental studies were compared with the model predictions: (a) batch re-suspension experiments with constant concentration of suspended particulate matter at two different temperatures (12 and 24 °C), and (b) simulated flood events in an annular flume. The model predicted both the final concentrations and the kinetics of 1-hydroxypyrene secretion into the gall bladder of exposed rainbow trout well. We were able to show that exhaustive exercise during exposure in simulated flood events can lead to increased levels of biliary metabolites and identified cardiac output and effective respiratory volume as the two most important factors for contaminant uptake. The results of our study clearly demonstrate the relevance and the necessity to investigate uptake of contaminants from suspended sediments under realistic exposure scenarios

  19. The Early Eocene equable climate problem: can perturbations of climate model parameters identify possible solutions?

    Science.gov (United States)

    Sagoo, Navjit; Valdes, Paul; Flecker, Rachel; Gregoire, Lauren J

    2013-10-28

    Geological data for the Early Eocene (56-47.8 Ma) indicate extensive global warming, with very warm temperatures at both poles. However, despite numerous attempts to simulate this warmth, there are remarkable data-model differences in the prediction of these polar surface temperatures, resulting in the so-called 'equable climate problem'. In this paper, for the first time an ensemble with a perturbed climate-sensitive model parameters approach has been applied to modelling the Early Eocene climate. We performed more than 100 simulations with perturbed physics parameters, and identified two simulations that have an optimal fit with the proxy data. We have simulated the warmth of the Early Eocene at 560 ppmv CO2, which is a much lower CO2 level than many other models. We investigate the changes in atmospheric circulation, cloud properties and ocean circulation that are common to these simulations and how they differ from the remaining simulations in order to understand what mechanisms contribute to the polar warming. The parameter set from one of the optimal Early Eocene simulations also produces a favourable fit for the last glacial maximum boundary climate and outperforms the control parameter set for the present day. Although this does not 'prove' that this model is correct, it is very encouraging that there is a parameter set that creates a climate model able to simulate well very different palaeoclimates and the present-day climate. Interestingly, to achieve the great warmth of the Early Eocene this version of the model does not have a strong future climate change Charney climate sensitivity. It produces a Charney climate sensitivity of 2.7(°)C, whereas the mean value of the 18 models in the IPCC Fourth Assessment Report (AR4) is 3.26(°)C±0.69(°)C. Thus, this value is within the range and below the mean of the models included in the AR4.

  20. Markov and semi-Markov switching linear mixed models used to identify forest tree growth components.

    Science.gov (United States)

    Chaubert-Pereira, Florence; Guédon, Yann; Lavergne, Christian; Trottier, Catherine

    2010-09-01

    Tree growth is assumed to be mainly the result of three components: (i) an endogenous component assumed to be structured as a succession of roughly stationary phases separated by marked change points that are asynchronous among individuals, (ii) a time-varying environmental component assumed to take the form of synchronous fluctuations among individuals, and (iii) an individual component corresponding mainly to the local environment of each tree. To identify and characterize these three components, we propose to use semi-Markov switching linear mixed models, i.e., models that combine linear mixed models in a semi-Markovian manner. The underlying semi-Markov chain represents the succession of growth phases and their lengths (endogenous component) whereas the linear mixed models attached to each state of the underlying semi-Markov chain represent-in the corresponding growth phase-both the influence of time-varying climatic covariates (environmental component) as fixed effects, and interindividual heterogeneity (individual component) as random effects. In this article, we address the estimation of Markov and semi-Markov switching linear mixed models in a general framework. We propose a Monte Carlo expectation-maximization like algorithm whose iterations decompose into three steps: (i) sampling of state sequences given random effects, (ii) prediction of random effects given state sequences, and (iii) maximization. The proposed statistical modeling approach is illustrated by the analysis of successive annual shoots along Corsican pine trunks influenced by climatic covariates. © 2009, The International Biometric Society.

  1. Scoping review identifies significant number of knowledge translation theories, models and frameworks with limited use.

    Science.gov (United States)

    Strifler, Lisa; Cardoso, Roberta; McGowan, Jessie; Cogo, Elise; Nincic, Vera; Khan, Paul A; Scott, Alistair; Ghassemi, Marco; MacDonald, Heather; Lai, Yonda; Treister, Victoria; Tricco, Andrea C; Straus, Sharon E

    2018-04-13

    To conduct a scoping review of knowledge translation (KT) theories, models and frameworks that have been used to guide dissemination or implementation of evidence-based interventions targeted to prevention and/or management of cancer or other chronic diseases. We used a comprehensive multistage search process from 2000-2016, which included traditional bibliographic database searching, searching using names of theories, models and frameworks, and cited reference searching. Two reviewers independently screened the literature and abstracted data. We found 596 studies reporting on the use of 159 KT theories, models or frameworks. A majority (87%) of the identified theories, models or frameworks were used in five or fewer studies, with 60% used once. The theories, models and frameworks were most commonly used to inform planning/design, implementation and evaluation activities, and least commonly used to inform dissemination and sustainability/scalability activities. Twenty-six were used across the full implementation spectrum (from planning/design to sustainability/scalability) either within or across studies. All were used for at least individual-level behavior change, while 48% were used for organization-level, 33% for community-level and 17% for system-level change. We found a significant number of KT theories, models and frameworks with a limited evidence base describing their use. Copyright © 2018. Published by Elsevier Inc.

  2. Helping boys at-risk of criminal activity: qualitative results of a multi-component intervention

    Directory of Open Access Journals (Sweden)

    Brennan Erin

    2011-05-01

    Full Text Available Abstract Background This qualitative study examines parent and child experiences of participation in a multi-component community-based program aimed at reducing offending behaviour, and increasing social competence in boys 6 to 11 years old in Hamilton, Ontario, Canada. The program builds on the concept of crime prevention through social development, and includes structured groups for the identified boy, parents, and siblings. Methods A sample of 35 families participating in the multi-component program took part in the qualitative study. Individual interviews with the boys, parents and siblings asked about changes in themselves, relationships with family and peers, and school after the group. Interviews were taped, transcribed and content analysis was used to code and interpret the data. Results Parents reported improvement in parenting skills and attainment of more effective communication skills, particularly with their children. Parents also found the relationships they formed with other parents in the program and the advice that they gained to be beneficial. Boys who participated in the program also benefited, with both parents and boys reporting improvements in boys' anger management skills, social skills, impulse control, and ability to recognize potentially volatile situations. Both parents and boys described overall improvement in family relationships and school-related success. Conclusions The qualitative data revealed that parents and boys participating in the multi-component program perceived improvements in a number of specific areas, including social competence of the boys. This has not been demonstrated as clearly in other evaluations of the program.

  3. Biodiversity and Climate Modeling Workshop Series: Identifying gaps and needs for improving large-scale biodiversity models

    Science.gov (United States)

    Weiskopf, S. R.; Myers, B.; Beard, T. D.; Jackson, S. T.; Tittensor, D.; Harfoot, M.; Senay, G. B.

    2017-12-01

    At the global scale, well-accepted global circulation models and agreed-upon scenarios for future climate from the Intergovernmental Panel on Climate Change (IPCC) are available. In contrast, biodiversity modeling at the global scale lacks analogous tools. While there is great interest in development of similar bodies and efforts for international monitoring and modelling of biodiversity at the global scale, equivalent modelling tools are in their infancy. This lack of global biodiversity models compared to the extensive array of general circulation models provides a unique opportunity to bring together climate, ecosystem, and biodiversity modeling experts to promote development of integrated approaches in modeling global biodiversity. Improved models are needed to understand how we are progressing towards the Aichi Biodiversity Targets, many of which are not on track to meet the 2020 goal, threatening global biodiversity conservation, monitoring, and sustainable use. We brought together biodiversity, climate, and remote sensing experts to try to 1) identify lessons learned from the climate community that can be used to improve global biodiversity models; 2) explore how NASA and other remote sensing products could be better integrated into global biodiversity models and 3) advance global biodiversity modeling, prediction, and forecasting to inform the Aichi Biodiversity Targets, the 2030 Sustainable Development Goals, and the Intergovernmental Platform on Biodiversity and Ecosystem Services Global Assessment of Biodiversity and Ecosystem Services. The 1st In-Person meeting focused on determining a roadmap for effective assessment of biodiversity model projections and forecasts by 2030 while integrating and assimilating remote sensing data and applying lessons learned, when appropriate, from climate modeling. Here, we present the outcomes and lessons learned from our first E-discussion and in-person meeting and discuss the next steps for future meetings.

  4. Modeling strategy to identify patients with primary immunodeficiency utilizing risk management and outcome measurement.

    Science.gov (United States)

    Modell, Vicki; Quinn, Jessica; Ginsberg, Grant; Gladue, Ron; Orange, Jordan; Modell, Fred

    2017-06-01

    This study seeks to generate analytic insights into risk management and probability of an identifiable primary immunodeficiency defect. The Jeffrey Modell Centers Network database, Jeffrey Modell Foundation's 10 Warning Signs, the 4 Stages of Testing Algorithm, physician-reported clinical outcomes, programs of physician education and public awareness, the SPIRIT® Analyzer, and newborn screening, taken together, generates P values of less than 0.05%. This indicates that the data results do not occur by chance, and that there is a better than 95% probability that the data are valid. The objectives are to improve patients' quality of life, while generating significant reduction of costs. The advances of the world's experts aligned with these JMF programs can generate analytic insights as to risk management and probability of an identifiable primary immunodeficiency defect. This strategy reduces the uncertainties related to primary immunodeficiency risks, as we can screen, test, identify, and treat undiagnosed patients. We can also address regional differences and prevalence, age, gender, treatment modalities, and sites of care, as well as economic benefits. These tools support high net benefits, substantial financial savings, and significant reduction of costs. All stakeholders, including patients, clinicians, pharmaceutical companies, third party payers, and government healthcare agencies, must address the earliest possible precise diagnosis, appropriate intervention and treatment, as well as stringent control of healthcare costs through risk assessment and outcome measurement. An affected patient is entitled to nothing less, and stakeholders are responsible to utilize tools currently available. Implementation offers a significant challenge to the entire primary immunodeficiency community.

  5. Video incident analysis of concussions in boys' high school lacrosse.

    Science.gov (United States)

    Lincoln, Andrew E; Caswell, Shane V; Almquist, Jon L; Dunn, Reginald E; Hinton, Richard Y

    2013-04-01

    Boys' lacrosse has one of the highest rates of concussion among boys' high school sports. A thorough understanding of injury mechanisms and game situations associated with concussions in boys' high school lacrosse is necessary to target injury prevention efforts. To characterize common game-play scenarios and mechanisms of injury associated with concussions in boys' high school lacrosse using game video. Descriptive epidemiological study. In 25 public high schools of a single school system, 518 boys' lacrosse games were videotaped by trained videographers during the 2008 and 2009 seasons. Video of concussion incidents was examined to identify game characteristics and injury mechanisms using a lacrosse-specific coding instrument. A total of 34 concussions were captured on video. All concussions resulted from player-to-player bodily contact. Players were most often injured when contact was unanticipated or players were defenseless (n = 19; 56%), attempting to pick up a loose ball (n = 16; 47%), and/or ball handling (n = 14; 41%). Most frequently, the striking player's head (n = 27; 79%) was involved in the collision, and the struck player's head was the initial point of impact in 20 incidents (59%). In 68% (n = 23) of cases, a subsequent impact with the playing surface occurred immediately after the initial impact. A penalty was called in 26% (n = 9) of collisions. Player-to-player contact was the mechanism for all concussions. Most commonly, injured players were unaware of the pending contact, and the striking player used his head to initiate contact. Further investigation of preventive measures such as education of coaches and officials and enforcement of rules designed to prevent intentional head-to-head contact is warranted to reduce the incidence of concussions in boys' lacrosse.

  6. "I am happy that God made me a boy": Zambian adolescent boys' perceptions about growing into manhood.

    Science.gov (United States)

    Dahlbäck, Elisabeth; Makelele, Patrick; Phillimon, Ndubani; Bawa, Yamba; Bergtröm, Staffan; Ransjö-Arvidson, Anna-Berit

    2003-04-01

    Adolescence is a period of transition during which a person is neither considered a child nor an adult. As little is known about adolescent boys' perceptions, norms, role models and gender relations that influence their male identity and behaviour, this qualitative study was conducted. Data were drawn from seven FGDs and twelve mails of adolescent boys (15-19 years old) residing in two townships outside Lusaka and Kitwe in Zambia. Findings show that growing up to a man entails a certain level of ambiguity and contradictory perceptions in terms of supposedly appropriate social and sexual behaviour but indicates a few alternatives. Based on the findings, we recommend that the information gap, misconceptions and anxiety among boys regarding their male identity should be addressed. The respondents suggested that an educational programme that will pay due attention to their needs and answer their questions should be designed and implemented with active involvement of male adolescent peers.

  7. A molecular systems approach to modelling human skin pigmentation: identifying underlying pathways and critical components.

    Science.gov (United States)

    Raghunath, Arathi; Sambarey, Awanti; Sharma, Neha; Mahadevan, Usha; Chandra, Nagasuma

    2015-04-29

    Ultraviolet radiations (UV) serve as an environmental stress for human skin, and result in melanogenesis, with the pigment melanin having protective effects against UV induced damage. This involves a dynamic and complex regulation of various biological processes that results in the expression of melanin in the outer most layers of the epidermis, where it can exert its protective effect. A comprehensive understanding of the underlying cross talk among different signalling molecules and cell types is only possible through a systems perspective. Increasing incidences of both melanoma and non-melanoma skin cancers necessitate the need to better comprehend UV mediated effects on skin pigmentation at a systems level, so as to ultimately evolve knowledge-based strategies for efficient protection and prevention of skin diseases. A network model for UV-mediated skin pigmentation in the epidermis was constructed and subjected to shortest path analysis. Virtual knock-outs were carried out to identify essential signalling components. We describe a network model for UV-mediated skin pigmentation in the epidermis. The model consists of 265 components (nodes) and 429 directed interactions among them, capturing the manner in which one component influences the other and channels information. Through shortest path analysis, we identify novel signalling pathways relevant to pigmentation. Virtual knock-outs or perturbations of specific nodes in the network have led to the identification of alternate modes of signalling as well as enabled determining essential nodes in the process. The model presented provides a comprehensive picture of UV mediated signalling manifesting in human skin pigmentation. A systems perspective helps provide a holistic purview of interconnections and complexity in the processes leading to pigmentation. The model described here is extensive yet amenable to expansion as new data is gathered. Through this study, we provide a list of important proteins essential

  8. Identifying the effects of parameter uncertainty on the reliability of riverbank stability modelling

    Science.gov (United States)

    Samadi, A.; Amiri-Tokaldany, E.; Darby, S. E.

    2009-05-01

    Bank retreat is a key process in fluvial dynamics affecting a wide range of physical, ecological and socioeconomic issues in the fluvial environment. To predict the undesirable effects of bank retreat and to inform effective measures to prevent it, a wide range of bank stability models have been presented in the literature. These models typically express bank stability by defining a factor of safety as the ratio of driving and resisting forces acting on the incipient failure block. These forces are affected by a range of controlling factors that include such aspects as the bank profile (bank height and angle), the geotechnical properties of the bank materials, as well as the hydrological status of the riverbanks. In this paper we evaluate the extent to which uncertainties in the parameterization of these controlling factors feed through to influence the reliability of the resulting bank stability estimate. This is achieved by employing a simple model of riverbank stability with respect to planar failure (which is the most common type of bank stability model) in a series of sensitivity tests and Monte Carlo analyses to identify, for each model parameter, the range of values that induce significant changes in the simulated factor of safety. These identified parameter value ranges are compared to empirically derived parameter uncertainties to determine whether they are likely to confound the reliability of the resulting bank stability calculations. Our results show that parameter uncertainties are typically high enough that the likelihood of generating unreliable predictions is typically very high (> ˜ 80% for predictions requiring a precision of < ± 15%). Because parameter uncertainties are derived primarily from the natural variability of the parameters, rather than measurement errors, much more careful attention should be paid to field sampling strategies, such that the parameter uncertainties and consequent prediction unreliabilities can be quantified more

  9. Gaussian Graphical Models Identify Networks of Dietary Intake in a German Adult Population.

    Science.gov (United States)

    Iqbal, Khalid; Buijsse, Brian; Wirth, Janine; Schulze, Matthias B; Floegel, Anna; Boeing, Heiner

    2016-03-01

    Data-reduction methods such as principal component analysis are often used to derive dietary patterns. However, such methods do not assess how foods are consumed in relation to each other. Gaussian graphical models (GGMs) are a set of novel methods that can address this issue. We sought to apply GGMs to derive sex-specific dietary intake networks representing consumption patterns in a German adult population. Dietary intake data from 10,780 men and 16,340 women of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort were cross-sectionally analyzed to construct dietary intake networks. Food intake for each participant was estimated using a 148-item food-frequency questionnaire that captured the intake of 49 food groups. GGMs were applied to log-transformed intakes (grams per day) of 49 food groups to construct sex-specific food networks. Semiparametric Gaussian copula graphical models (SGCGMs) were used to confirm GGM results. In men, GGMs identified 1 major dietary network that consisted of intakes of red meat, processed meat, cooked vegetables, sauces, potatoes, cabbage, poultry, legumes, mushrooms, soup, and whole-grain and refined breads. For women, a similar network was identified with the addition of fried potatoes. Other identified networks consisted of dairy products and sweet food groups. SGCGMs yielded results comparable to those of GGMs. GGMs are a powerful exploratory method that can be used to construct dietary networks representing dietary intake patterns that reveal how foods are consumed in relation to each other. GGMs indicated an apparent major role of red meat intake in a consumption pattern in the studied population. In the future, identified networks might be transformed into pattern scores for investigating their associations with health outcomes. © 2016 American Society for Nutrition.

  10. Chiropractic management using a brain-based model of care for a 15-year-old adolescent boy with migraine headaches and behavioral and learning difficulties: a case report

    Science.gov (United States)

    Kuhn, Kurt W.; Cambron, Jerrilyn

    2013-01-01

    Objective The purpose of this report is to describe chiropractic management, using a brain-based model of care, of a teen who had migraine headaches and several social and learning difficulties. Clinical features A 15-year-old adolescent boy with a chronic history of migraines and more than 10 years of learning and behavioral difficulties, including attention-deficit/hyperactivity disorder, obsessive compulsive disorder, and Tourette syndrome, presented for chiropractic care. Intervention and outcome The patient received spinal manipulation and was given home physical coordination activities that were contralateral to the side of the involved basal ganglia and ipsilateral to the involved cerebellum, along with interactive metronome training. Quantitative changes were noted in neurological soft signs, tests of variables of attention Conners’ Parent Rating Scale, the California Achievement Test, grade point, and reduction of medications. The patient reported qualitative improvements in tics, attention, reading, vision, health, relationships with his peers and his family, and self-esteem. Conclusion The patient with migraine headaches and learning difficulties responded well to the course of chiropractic care. This study suggests that there may be value in a brain-based model of care in the chiropractic management of conditions that are beyond musculoskeletal in nature. PMID:24396330

  11. Mathematical modeling identifies optimum lapatinib dosing schedules for the treatment of glioblastoma patients.

    Directory of Open Access Journals (Sweden)

    Shayna Stein

    2018-01-01

    Full Text Available Human primary glioblastomas (GBM often harbor mutations within the epidermal growth factor receptor (EGFR. Treatment of EGFR-mutant GBM cell lines with the EGFR/HER2 tyrosine kinase inhibitor lapatinib can effectively induce cell death in these models. However, EGFR inhibitors have shown little efficacy in the clinic, partly because of inappropriate dosing. Here, we developed a computational approach to model the in vitro cellular dynamics of the EGFR-mutant cell line SF268 in response to different lapatinib concentrations and dosing schedules. We then used this approach to identify an effective treatment strategy within the clinical toxicity limits of lapatinib, and developed a partial differential equation modeling approach to study the in vivo GBM treatment response by taking into account the heterogeneous and diffusive nature of the disease. Despite the inability of lapatinib to induce tumor regressions with a continuous daily schedule, our modeling approach consistently predicts that continuous dosing remains the best clinically feasible strategy for slowing down tumor growth and lowering overall tumor burden, compared to pulsatile schedules currently known to be tolerated, even when considering drug resistance, reduced lapatinib tumor concentrations due to the blood brain barrier, and the phenotypic switch from proliferative to migratory cell phenotypes that occurs in hypoxic microenvironments. Our mathematical modeling and statistical analysis platform provides a rational method for comparing treatment schedules in search for optimal dosing strategies for glioblastoma and other cancer types.

  12. Identifying Variability in Mental Models Within and Between Disciplines Caring for the Cardiac Surgical Patient.

    Science.gov (United States)

    Brown, Evans K H; Harder, Kathleen A; Apostolidou, Ioanna; Wahr, Joyce A; Shook, Douglas C; Farivar, R Saeid; Perry, Tjorvi E; Konia, Mojca R

    2017-07-01

    The cardiac operating room is a complex environment requiring efficient and effective communication between multiple disciplines. The objectives of this study were to identify and rank critical time points during the perioperative care of cardiac surgical patients, and to assess variability in responses, as a correlate of a shared mental model, regarding the importance of these time points between and within disciplines. Using Delphi technique methodology, panelists from 3 institutions were tasked with developing a list of critical time points, which were subsequently assigned to pause point (PP) categories. Panelists then rated these PPs on a 100-point visual analog scale. Descriptive statistics were expressed as percentages, medians, and interquartile ranges (IQRs). We defined low response variability between panelists as an IQR ≤ 20, moderate response variability as an IQR > 20 and ≤ 40, and high response variability as an IQR > 40. Panelists identified a total of 12 PPs. The PPs identified by the highest number of panelists were (1) before surgical incision, (2) before aortic cannulation, (3) before cardiopulmonary bypass (CPB) initiation, (4) before CPB separation, and (5) at time of transfer of care from operating room (OR) to intensive care unit (ICU) staff. There was low variability among panelists' ratings of the PP "before surgical incision," moderate response variability for the PPs "before separation from CPB," "before transfer from OR table to bed," and "at time of transfer of care from OR to ICU staff," and high response variability for the remaining 8 PPs. In addition, the perceived importance of each of these PPs varies between disciplines and between institutions. Cardiac surgical providers recognize distinct critical time points during cardiac surgery. However, there is a high degree of variability within and between disciplines as to the importance of these times, suggesting an absence of a shared mental model among disciplines caring for

  13. Framing black boys: parent, teacher, and student narratives of the academic lives of black boys.

    Science.gov (United States)

    Rowley, Stephanie J; Ross, Latisha; Lozada, Fantasy T; Williams, Amber; Gale, Adrian; Kurtz-Costes, Beth

    2014-01-01

    The discourse on Black boys tends to suggest that Black boys are in complete peril. We begin with evidence that Black boys are excelling in certain contexts (i.e., in certain states, in certain schools, and in certain courses). We then discuss the ways in which the narratives used by parents, teachers, and Black boys themselves may serve to further reinforce views that Black boys are beyond hope. Research on Black parents suggests that they tend to view their sons as vulnerable and have lower expectations for sons than for daughters. Studies of teachers show that they tend to view Black boys as unteachable, as social problems, and as scary. Research on Black boys shows that they are sometimes complicit in supporting these narratives by engaging in negative or ste reotypical behavior. We also include recent research that includes counter-narratives of Black boys. We end with suggestions for future research.

  14. A stochastic model for identifying differential gene pair co-expression patterns in prostate cancer progression

    Directory of Open Access Journals (Sweden)

    Mao Yu

    2009-07-01

    Full Text Available Abstract Background The identification of gene differential co-expression patterns between cancer stages is a newly developing method to reveal the underlying molecular mechanisms of carcinogenesis. Most researches of this subject lack an algorithm useful for performing a statistical significance assessment involving cancer progression. Lacking this specific algorithm is apparently absent in identifying precise gene pairs correlating to cancer progression. Results In this investigation we studied gene pair co-expression change by using a stochastic process model for approximating the underlying dynamic procedure of the co-expression change during cancer progression. Also, we presented a novel analytical method named 'Stochastic process model for Identifying differentially co-expressed Gene pair' (SIG method. This method has been applied to two well known prostate cancer data sets: hormone sensitive versus hormone resistant, and healthy versus cancerous. From these data sets, 428,582 gene pairs and 303,992 gene pairs were identified respectively. Afterwards, we used two different current statistical methods to the same data sets, which were developed to identify gene pair differential co-expression and did not consider cancer progression in algorithm. We then compared these results from three different perspectives: progression analysis, gene pair identification effectiveness analysis, and pathway enrichment analysis. Statistical methods were used to quantify the quality and performance of these different perspectives. They included: Re-identification Scale (RS and Progression Score (PS in progression analysis, True Positive Rate (TPR in gene pair analysis, and Pathway Enrichment Score (PES in pathway analysis. Our results show small values of RS and large values of PS, TPR, and PES; thus, suggesting that gene pairs identified by the SIG method are highly correlated with cancer progression, and highly enriched in disease-specific pathways. From

  15. Parent-Child Relationships of Boys in Different Offending Trajectories: A Developmental Perspective

    Science.gov (United States)

    Keijsers, Loes; Loeber, Rolf; Branje, Susan; Meeus, Wim

    2012-01-01

    Background: This study tested the theoretical assumption that transformations of parent-child relationships in late childhood and adolescence would differ for boys following different offending trajectories. Methods: Using longitudinal multiinformant data of 503 boys (ages 7-19), we conducted Growth Mixture Modeling to extract offending…

  16. Identifying the Minimum Model Features to Replicate Historic Morphodynamics of a Juvenile Delta

    Science.gov (United States)

    Czapiga, M. J.; Parker, G.

    2017-12-01

    We introduce a quasi-2D morphodynamic delta model that improves on past models that require many simplifying assumptions, e.g. a single channel representative of a channel network, fixed channel width, and spatially uniform deposition. Our model is useful for studying long-term progradation rates of any generic micro-tidal delta system with specification of: characteristic grain size, input water and sediment discharges and basin morphology. In particular, we relax the assumption of a single, implicit channel sweeping across the delta topset in favor of an implicit channel network. This network, coupled with recent research on channel-forming Shields number, quantitative assessments of the lateral depositional length of sand (corresponding loosely to levees) and length between bifurcations create a spatial web of deposition within the receiving basin. The depositional web includes spatial boundaries for areas infilling with sands carried as bed material load, as well as those filling via passive deposition of washload mud. Our main goal is to identify the minimum features necessary to accurately model the morphodynamics of channel number, width, depth, and overall delta progradation rate in a juvenile delta. We use the Wax Lake Delta in Louisiana as a test site due to its rapid growth in the last 40 years. Field data including topset/island bathymetry, channel bathymetry, topset/island width, channel width, number of channels, and radial topset length are compiled from US Army Corps of Engineers data for 1989, 1998, and 2006. Additional data is extracted from a DEM from 2015. These data are used as benchmarks for the hindcast model runs. The morphology of Wax Lake Delta is also strongly affected by a pre-delta substrate that acts as a lower "bedrock" boundary. Therefore, we also include closures for a bedrock-alluvial transition and an excess shear rate-law incision model to estimate bedrock incision. The model's framework is generic, but inclusion of individual

  17. Can Predictive Modeling Identify Head and Neck Oncology Patients at Risk for Readmission?

    Science.gov (United States)

    Manning, Amy M; Casper, Keith A; Peter, Kay St; Wilson, Keith M; Mark, Jonathan R; Collar, Ryan M

    2018-05-01

    Objective Unplanned readmission within 30 days is a contributor to health care costs in the United States. The use of predictive modeling during hospitalization to identify patients at risk for readmission offers a novel approach to quality improvement and cost reduction. Study Design Two-phase study including retrospective analysis of prospectively collected data followed by prospective longitudinal study. Setting Tertiary academic medical center. Subjects and Methods Prospectively collected data for patients undergoing surgical treatment for head and neck cancer from January 2013 to January 2015 were used to build predictive models for readmission within 30 days of discharge using logistic regression, classification and regression tree (CART) analysis, and random forests. One model (logistic regression) was then placed prospectively into the discharge workflow from March 2016 to May 2016 to determine the model's ability to predict which patients would be readmitted within 30 days. Results In total, 174 admissions had descriptive data. Thirty-two were excluded due to incomplete data. Logistic regression, CART, and random forest predictive models were constructed using the remaining 142 admissions. When applied to 106 consecutive prospective head and neck oncology patients at the time of discharge, the logistic regression model predicted readmissions with a specificity of 94%, a sensitivity of 47%, a negative predictive value of 90%, and a positive predictive value of 62% (odds ratio, 14.9; 95% confidence interval, 4.02-55.45). Conclusion Prospectively collected head and neck cancer databases can be used to develop predictive models that can accurately predict which patients will be readmitted. This offers valuable support for quality improvement initiatives and readmission-related cost reduction in head and neck cancer care.

  18. Probing the dynamics of identified neurons with a data-driven modeling approach.

    Directory of Open Access Journals (Sweden)

    Thomas Nowotny

    2008-07-01

    Full Text Available In controlling animal behavior the nervous system has to perform within the operational limits set by the requirements of each specific behavior. The implications for the corresponding range of suitable network, single neuron, and ion channel properties have remained elusive. In this article we approach the question of how well-constrained properties of neuronal systems may be on the neuronal level. We used large data sets of the activity of isolated invertebrate identified cells and built an accurate conductance-based model for this cell type using customized automated parameter estimation techniques. By direct inspection of the data we found that the variability of the neurons is larger when they are isolated from the circuit than when in the intact system. Furthermore, the responses of the neurons to perturbations appear to be more consistent than their autonomous behavior under stationary conditions. In the developed model, the constraints on different parameters that enforce appropriate model dynamics vary widely from some very tightly controlled parameters to others that are almost arbitrary. The model also allows predictions for the effect of blocking selected ionic currents and to prove that the origin of irregular dynamics in the neuron model is proper chaoticity and that this chaoticity is typical in an appropriate sense. Our results indicate that data driven models are useful tools for the in-depth analysis of neuronal dynamics. The better consistency of responses to perturbations, in the real neurons as well as in the model, suggests a paradigm shift away from measuring autonomous dynamics alone towards protocols of controlled perturbations. Our predictions for the impact of channel blockers on the neuronal dynamics and the proof of chaoticity underscore the wide scope of our approach.

  19. Data Mining and Pattern Recognition Models for Identifying Inherited Diseases: Challenges and Implications.

    Science.gov (United States)

    Iddamalgoda, Lahiru; Das, Partha S; Aponso, Achala; Sundararajan, Vijayaraghava S; Suravajhala, Prashanth; Valadi, Jayaraman K

    2016-01-01

    Data mining and pattern recognition methods reveal interesting findings in genetic studies, especially on how the genetic makeup is associated with inherited diseases. Although researchers have proposed various data mining models for biomedical approaches, there remains a challenge in accurately prioritizing the single nucleotide polymorphisms (SNP) associated with the disease. In this commentary, we review the state-of-art data mining and pattern recognition models for identifying inherited diseases and deliberate the need of binary classification- and scoring-based prioritization methods in determining causal variants. While we discuss the pros and cons associated with these methods known, we argue that the gene prioritization methods and the protein interaction (PPI) methods in conjunction with the K nearest neighbors' could be used in accurately categorizing the genetic factors in disease causation.

  20. Data mining and Pattern Recognizing Models for Identifying Inherited Diseases: Challenges and Implications

    Directory of Open Access Journals (Sweden)

    Lahiru Iddamalgoda

    2016-08-01

    Full Text Available Data mining and pattern recognition methods reveal interesting findings in genetic studies, especially on how genetic makeup is associated with inherited diseases. Although researchers have proposed various data mining models for biomedical approaches, there remains a challenge in accurately determining the responsible genetic factors for prioritizing the single nucleotide polymorphisms (SNP associated with the disease. In this commentary, we review the state-of-art data mining and pattern recognition models for identifying inherited diseases and deliberate the need of binary classification and scoring based prioritization methods for determining causal variants. While we discuss the pros and cons associated with these methods known, we argue that the gene prioritization methods and the protein interaction (PPI methods in conjunction with the K nearest neighbors’ could be used in accurately categorizing the genetic factors in disease causation

  1. Staphylococcus aureus virulence factors identified by using a high-throughput Caenorhabditis elegans-killing model.

    Science.gov (United States)

    Begun, Jakob; Sifri, Costi D; Goldman, Samuel; Calderwood, Stephen B; Ausubel, Frederick M

    2005-02-01

    Staphylococcus aureus is an important human pathogen that is also able to kill the model nematode Caenorhabditis elegans. We constructed a 2,950-member Tn917 transposon insertion library in S. aureus strain NCTC 8325. Twenty-one of these insertions exhibited attenuated C. elegans killing, and of these, 12 contained insertions in different genes or chromosomal locations. Ten of these 12 insertions showed attenuated killing phenotypes when transduced into two different S. aureus strains, and 5 of the 10 mutants correspond to genes that have not been previously identified in signature-tagged mutagenesis studies. These latter five mutants were tested in a murine renal abscess model, and one mutant harboring an insertion in nagD exhibited attenuated virulence. Interestingly, Tn917 was shown to have a very strong bias for insertions near the terminus of DNA replication.

  2. A Simple Model to Identify Risk of Sarcopenia and Physical Disability in HIV-Infected Patients.

    Science.gov (United States)

    Farinatti, Paulo; Paes, Lorena; Harris, Elizabeth A; Lopes, Gabriella O; Borges, Juliana P

    2017-09-01

    Farinatti, P, Paes, L, Harris, EA, Lopes, GO, and Borges, JP. A simple model to identify risk of sarcopenia and physical disability in HIV-infected patients. J Strength Cond Res 31(9): 2542-2551, 2017-Early detection of sarcopenia might help preventing muscle loss and disability in HIV-infected patients. This study proposed a model for estimating appendicular skeletal muscle mass (ASM) to calculate indices to identify "sarcopenia" (SA) and "risk for disability due to sarcopenia" (RSA) in patients with HIV. An equation to estimate ASM was developed in 56 patients (47.2 ± 6.9 years), with a cross-validation sample of 24 patients (48.1 ± 6.6 years). The model validity was determined by calculating, in both samples: (a) Concordance between actual vs. estimated ASM; (b) Correlations between actual/estimated ASM vs. peak torque (PT) and total work (TW) during isokinetic knee extension/flexion; (c) Agreement of patients classified with SA and RSA. The predictive equation was ASM (kg) = 7.77 (sex; F = 0/M = 1) + 0.26 (arm circumference; cm) + 0.38 (thigh circumference; cm) + 0.03 (Body Mass Index; kg·m) - 8.94 (R = 0.74; Radj = 0.72; SEE = 3.13 kg). Agreement between actual vs. estimated ASM was confirmed in validation (t = 0.081/p = 0.94; R = 0.86/p < 0.0001) and cross-validation (t = 0.12/p = 0.92; R = 0.87/p < 0.0001) samples. Regression characteristics in cross-validation sample (Radj = 0.80; SEE = 3.65) and PRESS (RPRESS = 0.69; SEEPRESS = 3.35) were compatible with the original model. Percent agreements for the classification of SA and RSA from indices calculated using actual and estimated ASM were of 87.5% and 77.2% (gamma correlations 0.72-1.0; p < 0.04) in validation, and 95.8% and 75.0% (gamma correlations 0.98-0.97; p < 0.001) in cross-validation sample, respectively. Correlations between actual/estimated ASM vs. PT (range 0.50-0.73, p ≤ 0.05) and TW (range 0.59-0.74, p ≤ 0.05) were similar in both samples. In conclusion, our model correctly estimated ASM

  3. Sensitivity of Ocean Reflectance Inversion Models for Identifying and Discriminating Between Phytoplankton Functional Groups

    Science.gov (United States)

    Werdell, P. Jeremy; Ooesler, Collin S.

    2012-01-01

    The daily, synoptic images provided by satellite ocean color instruments provide viable data streams for observing changes in the biogeochemistrY of marine ecosystems. Ocean reflectance inversion models (ORMs) provide a common mechanism for inverting the "color" of the water observed a satellite into marine inherent optical properties (lOPs) through a combination of empiricism and radiative transfer theory. lOPs, namely the spectral absorption and scattering characteristics of ocean water and its dissolved and particulate constituents, describe the contents of the upper ocean, information critical for furthering scientific understanding of biogeochemical oceanic processes. Many recent studies inferred marine particle sizes and discriminated between phytoplankton functional groups using remotely-sensed lOPs. While all demonstrated the viability of their approaches, few described the vertical distributions of the water column constituents under consideration and, thus, failed to report the biophysical conditions under which their model performed (e.g., the depth and thickness of the phytoplankton bloom(s)). We developed an ORM to remotely identifY Noctiluca miliaris and other phytoplankton functional types using satellite ocean color data records collected in the northern Arabian Sea. Here, we present results from analyses designed to evaluate the applicability and sensitivity of the ORM to varied biophysical conditions. Specifically, we: (1) synthesized a series of vertical profiles of spectral inherent optical properties that represent a wide variety of bio-optical conditions for the northern Arabian Sea under aN Miliaris bloom; (2) generated spectral remote-sensing reflectances from these profiles using Hydrolight; and, (3) applied the ORM to the synthesized reflectances to estimate the relative concentrations of diatoms and N Miliaris for each example. By comparing the estimates from the inversion model to those from synthesized vertical profiles, we were able to

  4. DESCARTES' RULE OF SIGNS AND THE IDENTIFIABILITY OF POPULATION DEMOGRAPHIC MODELS FROM GENOMIC VARIATION DATA.

    Science.gov (United States)

    Bhaskar, Anand; Song, Yun S

    2014-01-01

    The sample frequency spectrum (SFS) is a widely-used summary statistic of genomic variation in a sample of homologous DNA sequences. It provides a highly efficient dimensional reduction of large-scale population genomic data and its mathematical dependence on the underlying population demography is well understood, thus enabling the development of efficient inference algorithms. However, it has been recently shown that very different population demographies can actually generate the same SFS for arbitrarily large sample sizes. Although in principle this nonidentifiability issue poses a thorny challenge to statistical inference, the population size functions involved in the counterexamples are arguably not so biologically realistic. Here, we revisit this problem and examine the identifiability of demographic models under the restriction that the population sizes are piecewise-defined where each piece belongs to some family of biologically-motivated functions. Under this assumption, we prove that the expected SFS of a sample uniquely determines the underlying demographic model, provided that the sample is sufficiently large. We obtain a general bound on the sample size sufficient for identifiability; the bound depends on the number of pieces in the demographic model and also on the type of population size function in each piece. In the cases of piecewise-constant, piecewise-exponential and piecewise-generalized-exponential models, which are often assumed in population genomic inferences, we provide explicit formulas for the bounds as simple functions of the number of pieces. Lastly, we obtain analogous results for the "folded" SFS, which is often used when there is ambiguity as to which allelic type is ancestral. Our results are proved using a generalization of Descartes' rule of signs for polynomials to the Laplace transform of piecewise continuous functions.

  5. DESCARTES’ RULE OF SIGNS AND THE IDENTIFIABILITY OF POPULATION DEMOGRAPHIC MODELS FROM GENOMIC VARIATION DATA1

    Science.gov (United States)

    Bhaskar, Anand; Song, Yun S.

    2016-01-01

    The sample frequency spectrum (SFS) is a widely-used summary statistic of genomic variation in a sample of homologous DNA sequences. It provides a highly efficient dimensional reduction of large-scale population genomic data and its mathematical dependence on the underlying population demography is well understood, thus enabling the development of efficient inference algorithms. However, it has been recently shown that very different population demographies can actually generate the same SFS for arbitrarily large sample sizes. Although in principle this nonidentifiability issue poses a thorny challenge to statistical inference, the population size functions involved in the counterexamples are arguably not so biologically realistic. Here, we revisit this problem and examine the identifiability of demographic models under the restriction that the population sizes are piecewise-defined where each piece belongs to some family of biologically-motivated functions. Under this assumption, we prove that the expected SFS of a sample uniquely determines the underlying demographic model, provided that the sample is sufficiently large. We obtain a general bound on the sample size sufficient for identifiability; the bound depends on the number of pieces in the demographic model and also on the type of population size function in each piece. In the cases of piecewise-constant, piecewise-exponential and piecewise-generalized-exponential models, which are often assumed in population genomic inferences, we provide explicit formulas for the bounds as simple functions of the number of pieces. Lastly, we obtain analogous results for the “folded” SFS, which is often used when there is ambiguity as to which allelic type is ancestral. Our results are proved using a generalization of Descartes’ rule of signs for polynomials to the Laplace transform of piecewise continuous functions. PMID:28018011

  6. Growing Boys: Implementing a Boys' Empowerment Group in an Afterschool Program

    Science.gov (United States)

    Hall, Georgia; Charmaraman, Linda

    2011-01-01

    The process of establishing a healthy male identity can be difficult for many boys. The limited definitions of masculinity available to boys and men are generally characterized by competition, repression of fear and emotion, and physical and emotional strength. Boys of color and those of lower economic status tend to encounter even fewer healthy…

  7. To Be a Boy, To Be a Reader: Engaging Teen and Preteen Boys in Active Literacy.

    Science.gov (United States)

    Brozo, William G.

    When it comes to reading, teen and preteen boys are the most difficult students. This book addresses the growing concern among middle and high school teachers about boys' lack of literacy growth and independent reading. The book makes the case that boys are in the greatest need of help with literacy instruction and stresses the importance of…

  8. An Allometric Modelling Approach to Identify the Optimal Body Shape Associated with, and Differences between Brazilian and Peruvian Youth Motor Performance.

    Directory of Open Access Journals (Sweden)

    Simonete Silva

    Full Text Available Children from developed and developing countries differ in their body size and shape due to marked differences across their life history caused by social, economic and cultural differences which are also linked to their motor performance (MP. We used allometric models to identify size/shape characteristics associated with MP tests between Brazilian and Peruvian schoolchildren. A total of 4,560 subjects, 2,385 girls and 2,175 boys aged 9-15 years were studied. Height and weight were measured; biological maturation was estimated with the maturity offset technique; MP measures included the 12 minute run (12MR, handgrip strength (HG, standing long jump (SLJ and the shuttle run speed (SR tests; physical activity (PA was assessed using the Baecke questionnaire. A multiplicative allometric model was adopted to adjust for body size differences across countries. Reciprocal ponderal index (RPI was found to be the most suitable body shape indicator associated with the 12MR, SLJ, HG and SR performance. A positive maturation offset parameter was also associated with a better performance in SLJ, HG and SR tests. Sex differences were found in all motor tests. Brazilian youth showed better scores in MP than their Peruvian peers, even when controlling for their body size differences The current study identified the key body size associated with four body mass-dependent MP tests. Biological maturation and PA were associated with strength and motor performance. Sex differences were found in all motor tests, as well as across countries favoring Brazilian children even when accounting for their body size/shape differences.

  9. An Allometric Modelling Approach to Identify the Optimal Body Shape Associated with, and Differences between Brazilian and Peruvian Youth Motor Performance

    Science.gov (United States)

    Silva, Simonete; Bustamante, Alcibíades; Nevill, Alan; Katzmarzyk, Peter T.; Freitas, Duarte; Prista, António; Maia, José

    2016-01-01

    Children from developed and developing countries differ in their body size and shape due to marked differences across their life history caused by social, economic and cultural differences which are also linked to their motor performance (MP). We used allometric models to identify size/shape characteristics associated with MP tests between Brazilian and Peruvian schoolchildren. A total of 4,560 subjects, 2,385 girls and 2,175 boys aged 9–15 years were studied. Height and weight were measured; biological maturation was estimated with the maturity offset technique; MP measures included the 12 minute run (12MR), handgrip strength (HG), standing long jump (SLJ) and the shuttle run speed (SR) tests; physical activity (PA) was assessed using the Baecke questionnaire. A multiplicative allometric model was adopted to adjust for body size differences across countries. Reciprocal ponderal index (RPI) was found to be the most suitable body shape indicator associated with the 12MR, SLJ, HG and SR performance. A positive maturation offset parameter was also associated with a better performance in SLJ, HG and SR tests. Sex differences were found in all motor tests. Brazilian youth showed better scores in MP than their Peruvian peers, even when controlling for their body size differences The current study identified the key body size associated with four body mass-dependent MP tests. Biological maturation and PA were associated with strength and motor performance. Sex differences were found in all motor tests, as well as across countries favoring Brazilian children even when accounting for their body size/shape differences. PMID:26939118

  10. An Allometric Modelling Approach to Identify the Optimal Body Shape Associated with, and Differences between Brazilian and Peruvian Youth Motor Performance.

    Science.gov (United States)

    Silva, Simonete; Bustamante, Alcibíades; Nevill, Alan; Katzmarzyk, Peter T; Freitas, Duarte; Prista, António; Maia, José

    2016-01-01

    Children from developed and developing countries differ in their body size and shape due to marked differences across their life history caused by social, economic and cultural differences which are also linked to their motor performance (MP). We used allometric models to identify size/shape characteristics associated with MP tests between Brazilian and Peruvian schoolchildren. A total of 4,560 subjects, 2,385 girls and 2,175 boys aged 9-15 years were studied. Height and weight were measured; biological maturation was estimated with the maturity offset technique; MP measures included the 12 minute run (12MR), handgrip strength (HG), standing long jump (SLJ) and the shuttle run speed (SR) tests; physical activity (PA) was assessed using the Baecke questionnaire. A multiplicative allometric model was adopted to adjust for body size differences across countries. Reciprocal ponderal index (RPI) was found to be the most suitable body shape indicator associated with the 12MR, SLJ, HG and SR performance. A positive maturation offset parameter was also associated with a better performance in SLJ, HG and SR tests. Sex differences were found in all motor tests. Brazilian youth showed better scores in MP than their Peruvian peers, even when controlling for their body size differences The current study identified the key body size associated with four body mass-dependent MP tests. Biological maturation and PA were associated with strength and motor performance. Sex differences were found in all motor tests, as well as across countries favoring Brazilian children even when accounting for their body size/shape differences.

  11. Parallel approach to identifying the well-test interpretation model using a neurocomputer

    Science.gov (United States)

    May, Edward A., Jr.; Dagli, Cihan H.

    1996-03-01

    The well test is one of the primary diagnostic and predictive tools used in the analysis of oil and gas wells. In these tests, a pressure recording device is placed in the well and the pressure response is recorded over time under controlled flow conditions. The interpreted results are indicators of the well's ability to flow and the damage done to the formation surrounding the wellbore during drilling and completion. The results are used for many purposes, including reservoir modeling (simulation) and economic forecasting. The first step in the analysis is the identification of the Well-Test Interpretation (WTI) model, which determines the appropriate solution method. Mis-identification of the WTI model occurs due to noise and non-ideal reservoir conditions. Previous studies have shown that a feed-forward neural network using the backpropagation algorithm can be used to identify the WTI model. One of the drawbacks to this approach is, however, training time, which can run into days of CPU time on personal computers. In this paper a similar neural network is applied using both a personal computer and a neurocomputer. Input data processing, network design, and performance are discussed and compared. The results show that the neurocomputer greatly eases the burden of training and allows the network to outperform a similar network running on a personal computer.

  12. Targetable vulnerabilities in T- and NK-cell lymphomas identified through preclinical models.

    Science.gov (United States)

    Ng, Samuel Y; Yoshida, Noriaki; Christie, Amanda L; Ghandi, Mahmoud; Dharia, Neekesh V; Dempster, Joshua; Murakami, Mark; Shigemori, Kay; Morrow, Sara N; Van Scoyk, Alexandria; Cordero, Nicolas A; Stevenson, Kristen E; Puligandla, Maneka; Haas, Brian; Lo, Christopher; Meyers, Robin; Gao, Galen; Cherniack, Andrew; Louissaint, Abner; Nardi, Valentina; Thorner, Aaron R; Long, Henry; Qiu, Xintao; Morgan, Elizabeth A; Dorfman, David M; Fiore, Danilo; Jang, Julie; Epstein, Alan L; Dogan, Ahmet; Zhang, Yanming; Horwitz, Steven M; Jacobsen, Eric D; Santiago, Solimar; Ren, Jian-Guo; Guerlavais, Vincent; Annis, D Allen; Aivado, Manuel; Saleh, Mansoor N; Mehta, Amitkumar; Tsherniak, Aviad; Root, David; Vazquez, Francisca; Hahn, William C; Inghirami, Giorgio; Aster, Jon C; Weinstock, David M; Koch, Raphael

    2018-05-22

    T- and NK-cell lymphomas (TCL) are a heterogenous group of lymphoid malignancies with poor prognosis. In contrast to B-cell and myeloid malignancies, there are few preclinical models of TCLs, which has hampered the development of effective therapeutics. Here we establish and characterize preclinical models of TCL. We identify multiple vulnerabilities that are targetable with currently available agents (e.g., inhibitors of JAK2 or IKZF1) and demonstrate proof-of-principle for biomarker-driven therapies using patient-derived xenografts (PDXs). We show that MDM2 and MDMX are targetable vulnerabilities within TP53-wild-type TCLs. ALRN-6924, a stapled peptide that blocks interactions between p53 and both MDM2 and MDMX has potent in vitro activity and superior in vivo activity across 8 different PDX models compared to the standard-of-care agent romidepsin. ALRN-6924 induced a complete remission in a patient with TP53-wild-type angioimmunoblastic T-cell lymphoma, demonstrating the potential for rapid translation of discoveries from subtype-specific preclinical models.

  13. Hidden Markov model approach for identifying the modular framework of the protein backbone.

    Science.gov (United States)

    Camproux, A C; Tuffery, P; Chevrolat, J P; Boisvieux, J F; Hazout, S

    1999-12-01

    The hidden Markov model (HMM) was used to identify recurrent short 3D structural building blocks (SBBs) describing protein backbones, independently of any a priori knowledge. Polypeptide chains are decomposed into a series of short segments defined by their inter-alpha-carbon distances. Basically, the model takes into account the sequentiality of the observed segments and assumes that each one corresponds to one of several possible SBBs. Fitting the model to a database of non-redundant proteins allowed us to decode proteins in terms of 12 distinct SBBs with different roles in protein structure. Some SBBs correspond to classical regular secondary structures. Others correspond to a significant subdivision of their bounding regions previously considered to be a single pattern. The major contribution of the HMM is that this model implicitly takes into account the sequential connections between SBBs and thus describes the most probable pathways by which the blocks are connected to form the framework of the protein structures. Validation of the SBBs code was performed by extracting SBB series repeated in recoding proteins and examining their structural similarities. Preliminary results on the sequence specificity of SBBs suggest promising perspectives for the prediction of SBBs or series of SBBs from the protein sequences.

  14. A model-based approach to identify binding sites in CLIP-Seq data.

    Directory of Open Access Journals (Sweden)

    Tao Wang

    Full Text Available Cross-linking immunoprecipitation coupled with high-throughput sequencing (CLIP-Seq has made it possible to identify the targeting sites of RNA-binding proteins in various cell culture systems and tissue types on a genome-wide scale. Here we present a novel model-based approach (MiClip to identify high-confidence protein-RNA binding sites from CLIP-seq datasets. This approach assigns a probability score for each potential binding site to help prioritize subsequent validation experiments. The MiClip algorithm has been tested in both HITS-CLIP and PAR-CLIP datasets. In the HITS-CLIP dataset, the signal/noise ratios of miRNA seed motif enrichment produced by the MiClip approach are between 17% and 301% higher than those by the ad hoc method for the top 10 most enriched miRNAs. In the PAR-CLIP dataset, the MiClip approach can identify ∼50% more validated binding targets than the original ad hoc method and two recently published methods. To facilitate the application of the algorithm, we have released an R package, MiClip (http://cran.r-project.org/web/packages/MiClip/index.html, and a public web-based graphical user interface software (http://galaxy.qbrc.org/tool_runner?tool_id=mi_clip for customized analysis.

  15. C. elegans model identifies genetic modifiers of alpha-synuclein inclusion formation during aging.

    Directory of Open Access Journals (Sweden)

    Tjakko J van Ham

    2008-03-01

    Full Text Available Inclusions in the brain containing alpha-synuclein are the pathological hallmark of Parkinson's disease, but how these inclusions are formed and how this links to disease is poorly understood. We have developed a C. elegans model that makes it possible to monitor, in living animals, the formation of alpha-synuclein inclusions. In worms of old age, inclusions contain aggregated alpha- synuclein, resembling a critical pathological feature. We used genome-wide RNA interference to identify processes involved in inclusion formation, and identified 80 genes that, when knocked down, resulted in a premature increase in the number of inclusions. Quality control and vesicle-trafficking genes expressed in the ER/Golgi complex and vesicular compartments were overrepresented, indicating a specific role for these processes in alpha-synuclein inclusion formation. Suppressors include aging-associated genes, such as sir-2.1/SIRT1 and lagr-1/LASS2. Altogether, our data suggest a link between alpha-synuclein inclusion formation and cellular aging, likely through an endomembrane-related mechanism. The processes and genes identified here present a framework for further study of the disease mechanism and provide candidate susceptibility genes and drug targets for Parkinson's disease and other alpha-synuclein related disorders.

  16. Use of artificial intelligence to identify cardiovascular compromise in a model of hemorrhagic shock.

    Science.gov (United States)

    Glass, Todd F; Knapp, Jason; Amburn, Philip; Clay, Bruce A; Kabrisky, Matt; Rogers, Steven K; Garcia, Victor F

    2004-02-01

    To determine whether a prototype artificial intelligence system can identify volume of hemorrhage in a porcine model of controlled hemorrhagic shock. Prospective in vivo animal model of hemorrhagic shock. Research foundation animal surgical suite; computer laboratories of collaborating industry partner. Nineteen, juvenile, 25- to 35-kg, male and female swine. Anesthetized animals were instrumented for arterial and systemic venous pressure monitoring and blood sampling, and a splenectomy was performed. Following a 1-hr stabilization period, animals were hemorrhaged in aliquots to 10, 20, 30, 35, 40, 45, and 50% of total blood volume with a 10-min recovery between each aliquot. Data were downloaded directly from a commercial monitoring system into a proprietary PC-based software package for analysis. Arterial and venous blood gas values, glucose, and cardiac output were collected at specified intervals. Electrocardiogram, electroencephalogram, mixed venous oxygen saturation, temperature (core and blood), mean arterial pressure, pulmonary artery pressure, central venous pressure, pulse oximetry, and end-tidal CO(2) were continuously monitored and downloaded. Seventeen of 19 animals (89%) died as a direct result of hemorrhage. Stored data streams were analyzed by the prototype artificial intelligence system. For this project, the artificial intelligence system identified and compared three electrocardiographic features (R-R interval, QRS amplitude, and R-S interval) from each of nine unknown samples of the QRS complex. We found that the artificial intelligence system, trained on only three electrocardiographic features, identified hemorrhage volume with an average accuracy of 91% (95% confidence interval, 84-96%). These experiments demonstrate that an artificial intelligence system, based solely on the analysis of QRS amplitude, R-R interval, and R-S interval of an electrocardiogram, is able to accurately identify hemorrhage volume in a porcine model of lethal

  17. Identifying the decision to be supported: a review of papers from environmental modelling and software

    Science.gov (United States)

    Sojda, Richard S.; Chen, Serena H.; El Sawah, Sondoss; Guillaume, Joseph H.A.; Jakeman, A.J.; Lautenbach, Sven; McIntosh, Brian S.; Rizzoli, A.E.; Seppelt, Ralf; Struss, Peter; Voinov, Alexey; Volk, Martin

    2012-01-01

    Two of the basic tenets of decision support system efforts are to help identify and structure the decisions to be supported, and to then provide analysis in how those decisions might be best made. One example from wetland management would be that wildlife biologists must decide when to draw down water levels to optimise aquatic invertebrates as food for breeding ducks. Once such a decision is identified, a system or tool to help them make that decision in the face of current and projected climate conditions could be developed. We examined a random sample of 100 papers published from 2001-2011 in Environmental Modelling and Software that used the phrase “decision support system” or “decision support tool”, and which are characteristic of different sectors. In our review, 41% of the systems and tools related to the water resources sector, 34% were related to agriculture, and 22% to the conservation of fish, wildlife, and protected area management. Only 60% of the papers were deemed to be reporting on DSS. This was based on the papers reviewed not having directly identified a specific decision to be supported. We also report on the techniques that were used to identify the decisions, such as formal survey, focus group, expert opinion, or sole judgment of the author(s). The primary underlying modelling system, e.g., expert system, agent based model, Bayesian belief network, geographical information system (GIS), and the like was categorised next. Finally, since decision support typically should target some aspect of unstructured decisions, we subjectively determined to what degree this was the case. In only 23% of the papers reviewed, did the system appear to tackle unstructured decisions. This knowledge should be useful in helping workers in the field develop more effective systems and tools, especially by being exposed to the approaches in different, but related, disciplines. We propose that a standard blueprint for reporting on DSS be developed for

  18. A Fuzzy Computing Model for Identifying Polarity of Chinese Sentiment Words.

    Science.gov (United States)

    Wang, Bingkun; Huang, Yongfeng; Wu, Xian; Li, Xing

    2015-01-01

    With the spurt of online user-generated contents on web, sentiment analysis has become a very active research issue in data mining and natural language processing. As the most important indicator of sentiment, sentiment words which convey positive and negative polarity are quite instrumental for sentiment analysis. However, most of the existing methods for identifying polarity of sentiment words only consider the positive and negative polarity by the Cantor set, and no attention is paid to the fuzziness of the polarity intensity of sentiment words. In order to improve the performance, we propose a fuzzy computing model to identify the polarity of Chinese sentiment words in this paper. There are three major contributions in this paper. Firstly, we propose a method to compute polarity intensity of sentiment morphemes and sentiment words. Secondly, we construct a fuzzy sentiment classifier and propose two different methods to compute the parameter of the fuzzy classifier. Thirdly, we conduct extensive experiments on four sentiment words datasets and three review datasets, and the experimental results indicate that our model performs better than the state-of-the-art methods.

  19. Predictive model identifies key network regulators of cardiomyocyte mechano-signaling.

    Directory of Open Access Journals (Sweden)

    Philip M Tan

    2017-11-01

    Full Text Available Mechanical strain is a potent stimulus for growth and remodeling in cells. Although many pathways have been implicated in stretch-induced remodeling, the control structures by which signals from distinct mechano-sensors are integrated to modulate hypertrophy and gene expression in cardiomyocytes remain unclear. Here, we constructed and validated a predictive computational model of the cardiac mechano-signaling network in order to elucidate the mechanisms underlying signal integration. The model identifies calcium, actin, Ras, Raf1, PI3K, and JAK as key regulators of cardiac mechano-signaling and characterizes crosstalk logic imparting differential control of transcription by AT1R, integrins, and calcium channels. We find that while these regulators maintain mostly independent control over distinct groups of transcription factors, synergy between multiple pathways is necessary to activate all the transcription factors necessary for gene transcription and hypertrophy. We also identify a PKG-dependent mechanism by which valsartan/sacubitril, a combination drug recently approved for treating heart failure, inhibits stretch-induced hypertrophy, and predict further efficacious pairs of drug targets in the network through a network-wide combinatorial search.

  20. A Fuzzy Computing Model for Identifying Polarity of Chinese Sentiment Words

    Directory of Open Access Journals (Sweden)

    Bingkun Wang

    2015-01-01

    Full Text Available With the spurt of online user-generated contents on web, sentiment analysis has become a very active research issue in data mining and natural language processing. As the most important indicator of sentiment, sentiment words which convey positive and negative polarity are quite instrumental for sentiment analysis. However, most of the existing methods for identifying polarity of sentiment words only consider the positive and negative polarity by the Cantor set, and no attention is paid to the fuzziness of the polarity intensity of sentiment words. In order to improve the performance, we propose a fuzzy computing model to identify the polarity of Chinese sentiment words in this paper. There are three major contributions in this paper. Firstly, we propose a method to compute polarity intensity of sentiment morphemes and sentiment words. Secondly, we construct a fuzzy sentiment classifier and propose two different methods to compute the parameter of the fuzzy classifier. Thirdly, we conduct extensive experiments on four sentiment words datasets and three review datasets, and the experimental results indicate that our model performs better than the state-of-the-art methods.

  1. Identifying potential misfit items in cognitive process of learning engineering mathematics based on Rasch model

    International Nuclear Information System (INIS)

    Ataei, Sh; Mahmud, Z; Khalid, M N

    2014-01-01

    The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.

  2. A Fuzzy Computing Model for Identifying Polarity of Chinese Sentiment Words

    Science.gov (United States)

    Huang, Yongfeng; Wu, Xian; Li, Xing

    2015-01-01

    With the spurt of online user-generated contents on web, sentiment analysis has become a very active research issue in data mining and natural language processing. As the most important indicator of sentiment, sentiment words which convey positive and negative polarity are quite instrumental for sentiment analysis. However, most of the existing methods for identifying polarity of sentiment words only consider the positive and negative polarity by the Cantor set, and no attention is paid to the fuzziness of the polarity intensity of sentiment words. In order to improve the performance, we propose a fuzzy computing model to identify the polarity of Chinese sentiment words in this paper. There are three major contributions in this paper. Firstly, we propose a method to compute polarity intensity of sentiment morphemes and sentiment words. Secondly, we construct a fuzzy sentiment classifier and propose two different methods to compute the parameter of the fuzzy classifier. Thirdly, we conduct extensive experiments on four sentiment words datasets and three review datasets, and the experimental results indicate that our model performs better than the state-of-the-art methods. PMID:26106409

  3. Theoretical and Numerical Modeling of Transport of Land Use-Specific Fecal Source Identifiers

    Science.gov (United States)

    Bombardelli, F. A.; Sirikanchana, K. J.; Bae, S.; Wuertz, S.

    2008-12-01

    Microbial contamination in coastal and estuarine waters is of particular concern to public health officials. In this work, we advocate that well-formulated and developed mathematical and numerical transport models can be combined with modern molecular techniques in order to predict continuous concentrations of microbial indicators under diverse scenarios of interest, and that they can help in source identification of fecal pollution. As a proof of concept, we present initially the theory, numerical implementation and validation of one- and two-dimensional numerical models aimed at computing the distribution of fecal source identifiers in water bodies (based on Bacteroidales marker DNA sequences) coming from different land uses such as wildlife, livestock, humans, dogs or cats. These models have been developed to allow for source identification of fecal contamination in large bodies of water. We test the model predictions using diverse velocity fields and boundary conditions. Then, we present some preliminary results of an application of a three-dimensional water quality model to address the source of fecal contamination in the San Pablo Bay (SPB), United States, which constitutes an important sub-embayment of the San Francisco Bay. The transport equations for Bacteroidales include the processes of advection, diffusion, and decay of Bacteroidales. We discuss the validation of the developed models through comparisons of numerical results with field campaigns developed in the SPB. We determine the extent and importance of the contamination in the bay for two decay rates obtained from field observations, corresponding to total host-specific Bacteroidales DNA and host-specific viable Bacteroidales cells, respectively. Finally, we infer transport conditions in the SPB based on the numerical results, characterizing the fate of outflows coming from the Napa, Petaluma and Sonoma rivers.

  4. More Boys Wanted in Upstate New York

    Science.gov (United States)

    Robinson, Matt

    2010-01-01

    In spite of the popularity of TV shows like "American Idol" and "Glee," it can still be hard to convince boys that singing is cool. Therefore, choir directors who would like more boys to join their groups have their work cut out for them. Erin Belanger, music teacher at Stockbridge Valley central School in Munnsville, New York…

  5. Are Boys Discriminated in Swedish High Schools?

    Science.gov (United States)

    Hinnerich, Bjorn Tyrefors; Hoglin, Erik; Johannesson, Magnus

    2011-01-01

    Girls typically have higher grades than boys in school and recent research suggests that part of this gender difference may be due to discrimination of boys in grading. We rigorously test this in a field experiment where a random sample of the same tests in the Swedish language is subject to blind and non-blind grading. The non-blind test score is…

  6. Body Talk for Parents of Boys.

    Science.gov (United States)

    Stubbs, Margaret L.

    This pamphlet, targeted to boys' parents, discusses issues surrounding puberty. The introduction discusses education about menstruation and girls' and boys' attitudes towards it. Suggestions are offered for discussing menstruation with one's son. Suggestions focus on timing of introducing the topic; which parent takes responsibility for menstrual…

  7. Serotonergic contribution to boys' behavioral regulation.

    Science.gov (United States)

    Nantel-Vivier, Amélie; Pihl, Robert O; Young, Simon N; Parent, Sophie; Bélanger, Stacey Ageranioti; Sutton, Rachel; Dubois, Marie-Eve; Tremblay, Richard E; Séguin, Jean R

    2011-01-01

    Animal and human adult studies reveal a contribution of serotonin to behavior regulation. Whether these findings apply to children is unclear. The present study investigated serotonergic functioning in boys with a history of behavior regulation difficulties through a double-blind, acute tryptophan supplementation procedure. Participants were 23 boys (age 10 years) with a history of elevated physical aggression, recruited from a community sample. Eleven were given a chocolate milkshake supplemented with 500 mg tryptophan, and 12 received a chocolate milkshake without tryptophan. Boys engaged in a competitive reaction time game against a fictitious opponent, which assessed response to provocation, impulsivity, perspective taking, and sharing. Impulsivity was further assessed through a Go/No-Go paradigm. A computerized emotion recognition task and a staged instrumental help incident were also administered. Boys, regardless of group, responded similarly to high provocation by the fictitious opponent. However, boys in the tryptophan group adjusted their level of responding optimally as a function of the level of provocation, whereas boys in the control group significantly decreased their level of responding towards the end of the competition. Boys in the tryptophan group tended to show greater perspective taking, tended to better distinguish facial expressions of fear and happiness, and tended to provide greater instrumental help to the experimenter. The present study provides initial evidence for the feasibility of acute tryptophan supplementation in children and some effect of tryptophan supplementation on children's behaviors. Further studies are warranted to explore the potential impact of increased serotonergic functioning on boys' dominant and affiliative behaviors.

  8. Kernel density surface modelling as a means to identify significant concentrations of vulnerable marine ecosystem indicators.

    Directory of Open Access Journals (Sweden)

    Ellen Kenchington

    Full Text Available The United Nations General Assembly Resolution 61/105, concerning sustainable fisheries in the marine ecosystem, calls for the protection of vulnerable marine ecosystems (VME from destructive fishing practices. Subsequently, the Food and Agriculture Organization (FAO produced guidelines for identification of VME indicator species/taxa to assist in the implementation of the resolution, but recommended the development of case-specific operational definitions for their application. We applied kernel density estimation (KDE to research vessel trawl survey data from inside the fishing footprint of the Northwest Atlantic Fisheries Organization (NAFO Regulatory Area in the high seas of the northwest Atlantic to create biomass density surfaces for four VME indicator taxa: large-sized sponges, sea pens, small and large gorgonian corals. These VME indicator taxa were identified previously by NAFO using the fragility, life history characteristics and structural complexity criteria presented by FAO, along with an evaluation of their recovery trajectories. KDE, a non-parametric neighbour-based smoothing function, has been used previously in ecology to identify hotspots, that is, areas of relatively high biomass/abundance. We present a novel approach of examining relative changes in area under polygons created from encircling successive biomass categories on the KDE surface to identify "significant concentrations" of biomass, which we equate to VMEs. This allows identification of the VMEs from the broader distribution of the species in the study area. We provide independent assessments of the VMEs so identified using underwater images, benthic sampling with other gear types (dredges, cores, and/or published species distribution models of probability of occurrence, as available. For each VME indicator taxon we provide a brief review of their ecological function which will be important in future assessments of significant adverse impact on these habitats here

  9. Development of a model system to identify differences in spring and winter oat.

    Science.gov (United States)

    Chawade, Aakash; Lindén, Pernilla; Bräutigam, Marcus; Jonsson, Rickard; Jonsson, Anders; Moritz, Thomas; Olsson, Olof

    2012-01-01

    Our long-term goal is to develop a Swedish winter oat (Avena sativa). To identify molecular differences that correlate with winter hardiness, a winter oat model comprising of both non-hardy spring lines and winter hardy lines is needed. To achieve this, we selected 294 oat breeding lines, originating from various Russian, German, and American winter oat breeding programs and tested them in the field in south- and western Sweden. By assaying for winter survival and agricultural properties during four consecutive seasons, we identified 14 breeding lines of different origins that not only survived the winter but also were agronomically better than the rest. Laboratory tests including electrolytic leakage, controlled crown freezing assay, expression analysis of the AsVrn1 gene and monitoring of flowering time suggested that the American lines had the highest freezing tolerance, although the German lines performed better in the field. Finally, six lines constituting the two most freezing tolerant lines, two intermediate lines and two spring cultivars were chosen to build a winter oat model system. Metabolic profiling of non-acclimated and cold acclimated leaf tissue samples isolated from the six selected lines revealed differential expression patterns of 245 metabolites including several sugars, amino acids, organic acids and 181 hitherto unknown metabolites. The expression patterns of 107 metabolites showed significant interactions with either a cultivar or a time-point. Further identification, characterisation and validation of these metabolites will lead to an increased understanding of the cold acclimation process in oats. Furthermore, by using the winter oat model system, differential sequencing of crown mRNA populations would lead to identification of various biomarkers to facilitate winter oat breeding.

  10. Experimentally Identify the Effective Plume Chimney over a Natural Draft Chimney Model

    Science.gov (United States)

    Rahman, M. M.; Chu, C. M.; Tahir, A. M.; Ismail, M. A. bin; Misran, M. S. bin; Ling, L. S.

    2017-07-01

    The demands of energy are in increasing order due to rapid industrialization and urbanization. The researchers and scientists are working hard to improve the performance of the industry so that the energy consumption can be reduced significantly. Industries like power plant, timber processing plant, oil refinery, etc. performance mainly depend on the cooling tower chimney’s performance, either natural draft or forced draft. Chimney is used to create sufficient draft, so that air can flow through it. Cold inflow or flow reversal at chimney exit is one of the main identified problems that may alter the overall plant performance. The presence Effective Plume Chimney (EPC) is an indication of cold inflow free operation of natural draft chimney. Different mathematical model equations are used to estimate the EPC height over the heat exchanger or hot surface. In this paper, it is aim to identify the EPC experimentally. In order to do that, horizontal temperature profiling is done at the exit of the chimneys of face area 0.56m2, 1.00m2 and 2.25m2. A wire mesh screen is installed at chimneys exit to ensure cold inflow chimney operation. It is found that EPC exists in all modified chimney models and the heights of EPC varied from 1 cm to 9 cm. The mathematical models indicate that the estimated heights of EPC varied from 1 cm to 2.3 cm. Smoke test is also conducted to ensure the existence of EPC and cold inflow free option of chimney. Smoke test results confirmed the presence of EPC and cold inflow free operation of chimney. The performance of the cold inflow free chimney is increased by 50% to 90% than normal chimney.

  11. Identifying the Basal Ganglia network model markers for medication-induced impulsivity in Parkinson's disease patients.

    Directory of Open Access Journals (Sweden)

    Pragathi Priyadharsini Balasubramani

    Full Text Available Impulsivity, i.e. irresistibility in the execution of actions, may be prominent in Parkinson's disease (PD patients who are treated with dopamine precursors or dopamine receptor agonists. In this study, we combine clinical investigations with computational modeling to explore whether impulsivity in PD patients on medication may arise as a result of abnormalities in risk, reward and punishment learning. In order to empirically assess learning outcomes involving risk, reward and punishment, four subject groups were examined: healthy controls, ON medication PD patients with impulse control disorder (PD-ON ICD or without ICD (PD-ON non-ICD, and OFF medication PD patients (PD-OFF. A neural network model of the Basal Ganglia (BG that has the capacity to predict the dysfunction of both the dopaminergic (DA and the serotonergic (5HT neuromodulator systems was developed and used to facilitate the interpretation of experimental results. In the model, the BG action selection dynamics were mimicked using a utility function based decision making framework, with DA controlling reward prediction and 5HT controlling punishment and risk predictions. The striatal model included three pools of Medium Spiny Neurons (MSNs, with D1 receptor (R alone, D2R alone and co-expressing D1R-D2R. Empirical studies showed that reward optimality was increased in PD-ON ICD patients while punishment optimality was increased in PD-OFF patients. Empirical studies also revealed that PD-ON ICD subjects had lower reaction times (RT compared to that of the PD-ON non-ICD patients. Computational modeling suggested that PD-OFF patients have higher punishment sensitivity, while healthy controls showed comparatively higher risk sensitivity. A significant decrease in sensitivity to punishment and risk was crucial for explaining behavioral changes observed in PD-ON ICD patients. Our results highlight the power of computational modelling for identifying neuronal circuitry implicated in learning

  12. Identifying the Basal Ganglia network model markers for medication-induced impulsivity in Parkinson's disease patients.

    Science.gov (United States)

    Balasubramani, Pragathi Priyadharsini; Chakravarthy, V Srinivasa; Ali, Manal; Ravindran, Balaraman; Moustafa, Ahmed A

    2015-01-01

    Impulsivity, i.e. irresistibility in the execution of actions, may be prominent in Parkinson's disease (PD) patients who are treated with dopamine precursors or dopamine receptor agonists. In this study, we combine clinical investigations with computational modeling to explore whether impulsivity in PD patients on medication may arise as a result of abnormalities in risk, reward and punishment learning. In order to empirically assess learning outcomes involving risk, reward and punishment, four subject groups were examined: healthy controls, ON medication PD patients with impulse control disorder (PD-ON ICD) or without ICD (PD-ON non-ICD), and OFF medication PD patients (PD-OFF). A neural network model of the Basal Ganglia (BG) that has the capacity to predict the dysfunction of both the dopaminergic (DA) and the serotonergic (5HT) neuromodulator systems was developed and used to facilitate the interpretation of experimental results. In the model, the BG action selection dynamics were mimicked using a utility function based decision making framework, with DA controlling reward prediction and 5HT controlling punishment and risk predictions. The striatal model included three pools of Medium Spiny Neurons (MSNs), with D1 receptor (R) alone, D2R alone and co-expressing D1R-D2R. Empirical studies showed that reward optimality was increased in PD-ON ICD patients while punishment optimality was increased in PD-OFF patients. Empirical studies also revealed that PD-ON ICD subjects had lower reaction times (RT) compared to that of the PD-ON non-ICD patients. Computational modeling suggested that PD-OFF patients have higher punishment sensitivity, while healthy controls showed comparatively higher risk sensitivity. A significant decrease in sensitivity to punishment and risk was crucial for explaining behavioral changes observed in PD-ON ICD patients. Our results highlight the power of computational modelling for identifying neuronal circuitry implicated in learning, and its

  13. Identifying the environmental factors that effect within canopy BVOC loss using a multilevel canopy model

    Science.gov (United States)

    Chan, W. S.; Fuentes, J. D.; Lerdau, M.

    2010-12-01

    This presentation will provide research findings to evaluate the hypothesis that the loss of biogenic volatile organic compound (BVOC) within plant canopies is dynamic and depends on factors such as plant canopy architecture (height and leaf area distribution), atmospheric turbulence, concentration of oxidants (OH, O3, NO3), and the reactivity of BVOC species. Results will be presented from a new one dimensional, multilevel canopy model that couples algorithms for canopy microclimate, leaf physiology, BVOC emission, turbulent transport, and atmospheric chemistry to investigate the relative importance of factors that impact BVOC loss within a forest canopy. Model sensitivity tests will be presented and discussed to identify factors driving canopy loss. Results show isoprene and monoterpene canopy losses as high as 9 and 18%, respectively, for tall canopies during the daytime. We hypothesize that canopy height and wind speed (i.e. canopy residence time) may be the most important in dictating within-canopy loss. This work will reduce the error in bottom-up flux estimates of BVOCs and ultimately improve parameterizations of BVOC sources in air quality models by accounting for within canopy processes.

  14. A model for genetic and epigenetic regulatory networks identifies rare pathways for transcription factor induced pluripotency

    Science.gov (United States)

    Artyomov, Maxim; Meissner, Alex; Chakraborty, Arup

    2010-03-01

    Most cells in an organism have the same DNA. Yet, different cell types express different proteins and carry out different functions. This is because of epigenetic differences; i.e., DNA in different cell types is packaged distinctly, making it hard to express certain genes while facilitating the expression of others. During development, upon receipt of appropriate cues, pluripotent embryonic stem cells differentiate into diverse cell types that make up the organism (e.g., a human). There has long been an effort to make this process go backward -- i.e., reprogram a differentiated cell (e.g., a skin cell) to pluripotent status. Recently, this has been achieved by transfecting certain transcription factors into differentiated cells. This method does not use embryonic material and promises the development of patient-specific regenerative medicine, but it is inefficient. The mechanisms that make reprogramming rare, or even possible, are poorly understood. We have developed the first computational model of transcription factor-induced reprogramming. Results obtained from the model are consistent with diverse observations, and identify the rare pathways that allow reprogramming to occur. If validated, our model could be further developed to design optimal strategies for reprogramming and shed light on basic questions in biology.

  15. Identifying the Correlation between Water Quality Data and LOADEST Model Behavior in Annual Sediment Load Estimations

    Directory of Open Access Journals (Sweden)

    Youn Shik Park

    2016-08-01

    Full Text Available Water quality samples are typically collected less frequently than flow since water quality sampling is costly. Load Estimator (LOADEST, provided by the United States Geological Survey, is used to predict water quality concentration (or load on days when flow data are measured so that the water quality data are sufficient for annual pollutant load estimation. However, there is a need to identify water quality data requirements for accurate pollutant load estimation. Measured daily sediment data were collected from 211 streams. Estimated annual sediment loads from LOADEST and subsampled data were compared to the measured annual sediment loads (true load. The means of flow for calibration data were correlated to model behavior. A regression equation was developed to compute the required mean of flow in calibration data to best calibrate the LOADEST regression model coefficients. LOADEST runs were performed to investigate the correlation between the mean flow in calibration data and model behaviors as daily water quality data were subsampled. LOADEST calibration data used sediment concentration data for flows suggested by the regression equation. Using the mean flow calibrated by the regression equation reduced errors in annual sediment load estimation from −39.7% to −10.8% compared to using all available data.

  16. Modelling categorical data to identify factors influencing concern for the natural environment in Iran.

    Science.gov (United States)

    Parizanganeh, Abdolhossein; Lakhan, V Chris; Yazdani, Mahmoud; Ahmad, Sajid R

    2011-10-01

    Loglinear modelling techniques were used to identify the interactions and interrelationships underlying categorical environmental concern data collected from 9062 respondents in Iran. After fitting various loglinear models to the data, the most parsimonious model highlighted that a combination of interacting factors, namely educational attainment, age, gender, and residential location were responsible for influencing personal concern for the environment. Although high educational attainment had a close correspondence with high concern for the environment the loglinear results, when visualized with a geographical information system, demonstrated wide spatial variations in educational attainment and concern for the environment. Nearly two-thirds of the respondents were not highly educated, and were therefore not highly concerned for the environment. The finding that both rural and urban male and female respondents in the 15-24 years age category, with 10-12 years of education, had the strongest interaction with personal concern for the environment could be beneficial for policy planners to utilize education as the primary instrument to enhance environmental governance and prospects for sustainable development. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Identifying model pollutants to investigate biodegradation of hazardous XOCs in WWTPs

    Energy Technology Data Exchange (ETDEWEB)

    Press-Kristensen, Kaare; Ledin, Anna; Schmidt, Jens Ejbye; Henze, Mogens [Department of Environment and Resources, Technical University of Denmark Building 115, 2800 Lyngby (Denmark)

    2007-02-01

    Xenobiotic organic compounds (XOCs) in wastewater treatment plant (WWTP) effluents might cause toxic effects in ecosystems. Several investigations have emphasized biodegradation as an important removal mechanism to reduce pollution with XOCs from WWTP effluents. The aim of the study was to design a screening tool to identify and select hazardous model pollutants for the further investigation of biodegradation in WWTPs. The screening tool consists of three criteria: The XOC is present in WWTP effluents, the XOC constitutes an intolerable risk in drinking water or the environment, and the XOC is expected to be biodegradable in WWTPs. The screening tool was tested on bisphenol A (BPA), carbamazepine (CBZ), di(2ethylhexyl)-phthalate (DEHP), 17{beta}-estradiol (E2), estrone (E1), 17{alpha}-ethinyloetradiol (EE2), ibuprofen, naproxen, nonylphenol (NP), and octylphenol (OP). BPA, DEHP, E2, E1, EE2, and NP passed all criteria in the screening tool and were selected as model pollutants. OP did not pass the filter and was rejected as model pollutant. CBZ, ibuprofen, and naproxen were not finally evaluated due to insufficient data. (author)

  18. Serum AMH levels are lower in healthy boys who develop pubertal gynaecomastia

    DEFF Research Database (Denmark)

    Mieritz, Mikkel G.; Hagen, Casper P.; Almstrup, Kristian

    2015-01-01

    Background: Pubertal gynaecomastia is thought to be a clinical sign of an oestrogen-androgen imbalance, affecting up to 60% of boys. In most cases no underlying endocrinopathy can be identified. In boys, Anti-mullerian hormone (AMH) is produced by immature Sertoli cells and circulating level...... decreases as testosterone increases during pubertal maturation. In a previous cross sectional study we found significant lower levels of AMH in boys with pubertal gynaecomastia (Mieritz et al., Clin Endocrinol, 2013). Objective and hypotheses: To investigate serum AMH levels and genetic polymorphisms...... in boys with or without gynaecomastia. Method: 99 healthy Danish boys (aged 5.8-16.4 years) were followed in a prospective cohort over 8 years with semi-annual examinations (total examinations, n=951), including breast palpations and blood samples. Serum AMH concentrations were analysed by immunoassay...

  19. Prediction equation for lower limbs lean soft tissue in circumpubertal boys using anthropometry and biological maturation.

    Directory of Open Access Journals (Sweden)

    João Valente-dos-Santos

    Full Text Available Lean soft tissue (LST, a surrogate of skeletal muscle mass, is largely limited to appendicular body regions. Simple and accurate methods to estimate lower limbs LST are often used in attempts to partition out the influence of body size on performance outputs. The aim of the current study was to develop and cross-validate a new model to predict lower limbs LST in boys aged 10-13 years, using dual-energy X-ray absorptiometry (DXA as the reference method. Total body and segmental (lower limbs composition were assessed with a Hologic Explorer-W QDR DXA scanner in a cross-sectional sample of 75 Portuguese boys (144.8±6.4 cm; 40.2±9.0 kg. Skinfolds were measured at the anterior and posterior mid-thigh, and medial calf. Circumferences were measured at the proximal, mid and distal thigh. Leg length was estimated as stature minus sitting height. Current stature expressed as a percentage of attained predicted mature stature (PMS was used as an estimate of biological maturity status. Backward proportional allometric models were used to identify the model with the best statistical fit: ln (lower limbs LST  = 0.838× ln (body mass +0.476× ln (leg length - 0.135× ln (mid-thigh circumference - 0.053× ln (anterior mid-thigh skinfold - 0.098× ln (medial calf skinfold - 2.680+0.010× (percentage of attained PMS (R = 0.95. The obtained equation was cross-validated using the predicted residuals sum of squares statistics (PRESS method (R2PRESS = 0.90. Deming repression analysis between predicted and current lower limbs LST showed a standard error of estimation of 0.52 kg (95% limits of agreement: 0.77 to -1.27 kg. The new model accurately predicts lower limbs LST in circumpubertal boys.

  20. Identifying generalized Fitzhugh-Nagumo equation from a numerical solution of Hodgkin-Huxley model

    Directory of Open Access Journals (Sweden)

    Nikola V. Georgiev

    2003-01-01

    Full Text Available An analytic time series in the form of numerical solution (in an appropriate finite time interval of the Hodgkin-Huxley current clamped (HHCC system of four differential equations, well known in the neurophysiology as an exact empirical model of excitation of a giant axon of Loligo, is presented. Then we search for a second-order differential equation of generalized Fitzhugh-Nagumo (GFN type, having as a solution the given single component (action potential of the numerical solution. The given time series is used as a basis for reconstructing orders, powers, and coefficients of the polynomial right-hand sides of GFN equation approximately governing the process of action potential. For this purpose, a new geometrical method for determining phase space dimension of the unknown dynamical system (GFN equation and a specific modification of least squares method for identifying unknown coefficients are developed and applied.

  1. A modified Leslie-Gower predator-prey interaction model and parameter identifiability

    Science.gov (United States)

    Tripathi, Jai Prakash; Meghwani, Suraj S.; Thakur, Manoj; Abbas, Syed

    2018-01-01

    In this work, bifurcation and a systematic approach for estimation of identifiable parameters of a modified Leslie-Gower predator-prey system with Crowley-Martin functional response and prey refuge is discussed. Global asymptotic stability is discussed by applying fluctuation lemma. The system undergoes into Hopf bifurcation with respect to parameters intrinsic growth rate of predators (s) and prey reserve (m). The stability of Hopf bifurcation is also discussed by calculating Lyapunov number. The sensitivity analysis of the considered model system with respect to all variables is performed which also supports our theoretical study. To estimate the unknown parameter from the data, an optimization procedure (pseudo-random search algorithm) is adopted. System responses and phase plots for estimated parameters are also compared with true noise free data. It is found that the system dynamics with true set of parametric values is similar to the estimated parametric values. Numerical simulations are presented to substantiate the analytical findings.

  2. Effect of Friction-Induced Nonlinearity on OMA-Identified Dynamic Characteristics of Offshore Platform Models

    DEFF Research Database (Denmark)

    Friis, Tobias; Orfanos, Antonios; Katsanos, Evangelos

    The identification of the modal characteristics of engineering systems under operational conditions is commonly conducted with the use of the Operational Modal Analysis (OMA), being a class of useful tools employed within various fields of structural, mechanical as well as marine and naval...... engineering. The current OMA methods have been advanced on the basis of two fundamental, though, restrictive assumptions: (i) linearity and (ii) stationarity. Nevertheless, there are several applications that are inherently related to various nonlinear mechanisms, which, in turn, violate the two cornerstones...... of OMA and hence, question its robustness and efficiency. Along these lines, the current study addresses the effect of friction-induced nonlinearity on OMA-identified dynamic characteristics of an experimental set up consisting of a pair of reduced scale offshore platform models that are connected...

  3. Identifying bubble collapse in a hydrothermal system using hiddden Markov models

    Science.gov (United States)

    Dawson, Phillip B.; Benitez, M.C.; Lowenstern, Jacob B.; Chouet, Bernard A.

    2012-01-01

    Beginning in July 2003 and lasting through September 2003, the Norris Geyser Basin in Yellowstone National Park exhibited an unusual increase in ground temperature and hydrothermal activity. Using hidden Markov model theory, we identify over five million high-frequency (>15 Hz) seismic events observed at a temporary seismic station deployed in the basin in response to the increase in hydrothermal activity. The source of these seismic events is constrained to within ~100 m of the station, and produced ~3500–5500 events per hour with mean durations of ~0.35–0.45 s. The seismic event rate, air temperature, hydrologic temperatures, and surficial water flow of the geyser basin exhibited a marked diurnal pattern that was closely associated with solar thermal radiance. We interpret the source of the seismicity to be due to the collapse of small steam bubbles in the hydrothermal system, with the rate of collapse being controlled by surficial temperatures and daytime evaporation rates.

  4. Effective spreading from multiple leaders identified by percolation in the susceptible-infected-recovered (SIR) model

    Science.gov (United States)

    Ji, Shenggong; Lü, Linyuan; Yeung, Chi Ho; Hu, Yanqing

    2017-07-01

    Social networks constitute a new platform for information propagation, but its success is crucially dependent on the choice of spreaders who initiate the spreading of information. In this paper, we remove edges in a network at random and the network segments into isolated clusters. The most important nodes in each cluster then form a set of influential spreaders, such that news propagating from them would lead to extensive coverage and minimal redundancy. The method utilizes the similarities between the segmented networks before percolation and the coverage of information propagation in each social cluster to obtain a set of distributed and coordinated spreaders. Our tests of implementing the susceptible-infected-recovered model on Facebook and Enron email networks show that this method outperforms conventional centrality-based methods in terms of spreadability and coverage redundancy. The suggested way of identifying influential spreaders thus sheds light on a new paradigm of information propagation in social networks.

  5. Fractal based modelling and analysis of electromyography (EMG) to identify subtle actions.

    Science.gov (United States)

    Arjunan, Sridhar P; Kumar, Dinesh K

    2007-01-01

    The paper reports the use of fractal theory and fractal dimension to study the non-linear properties of surface electromyogram (sEMG) and to use these properties to classify subtle hand actions. The paper reports identifying a new feature of the fractal dimension, the bias that has been found to be useful in modelling the muscle activity and of sEMG. Experimental results demonstrate that the feature set consisting of bias values and fractal dimension of the recordings is suitable for classification of sEMG against the different hand gestures. The scatter plots demonstrate the presence of simple relationships of these features against the four hand gestures. The results indicate that there is small inter-experimental variation but large inter-subject variation. This may be due to differences in the size and shape of muscles for different subjects. The possible applications of this research include use in developing prosthetic hands, controlling machines and computers.

  6. A Hidden Markov Movement Model for rapidly identifying behavioral states from animal tracks

    DEFF Research Database (Denmark)

    Whoriskey, Kim; Auger-Méthé, Marie; Albertsen, Christoffer Moesgaard

    2017-01-01

    by fitting it to real tracks from a grey seal, lake trout, and blue shark, as well as to simulated data. 4. The HMMM is a fast and reliable tool for making meaningful inference from animal movement data that is ideally suited for ecologists who want to use the popular DCRWS implementation for highly accurate......1. Electronic telemetry is frequently used to document animal movement through time. Methods that can identify underlying behaviors driving specific movement patterns can help us understand how and why animals use available space, thereby aiding conservation and management efforts. For aquatic...... animal tracking data with significant measurement error, a Bayesian state-space model called the first-Difference Correlated Random Walk with Switching (DCRWS) has often been used for this purpose. However, for aquatic animals, highly accurate tracking data of animal movement are now becoming more common...

  7. Unitary input DEA model to identify beef cattle production systems typologies

    Directory of Open Access Journals (Sweden)

    Eliane Gonçalves Gomes

    2012-08-01

    Full Text Available The cow-calf beef production sector in Brazil has a wide variety of operating systems. This suggests the identification and the characterization of homogeneous regions of production, with consequent implementation of actions to achieve its sustainability. In this paper we attempted to measure the performance of 21 livestock modal production systems, in their cow-calf phase. We measured the performance of these systems, considering husbandry and production variables. The proposed approach is based on data envelopment analysis (DEA. We used unitary input DEA model, with apparent input orientation, together with the efficiency measurements generated by the inverted DEA frontier. We identified five modal production systems typologies, using the isoefficiency layers approach. The results showed that the knowledge and the processes management are the most important factors for improving the efficiency of beef cattle production systems.

  8. Parent-identified barriers to pediatric health care: a process-oriented model.

    Science.gov (United States)

    Sobo, Elisa J; Seid, Michael; Reyes Gelhard, Leticia

    2006-02-01

    To further understand barriers to care as experienced by health care consumers, and to demonstrate the importance of conjoining qualitative and quantitative health services research. Transcripts from focus groups conducted in San Diego with English- and Spanish-speaking parents of children with special health care needs. Participants were asked about the barriers to care they had experienced or perceived, and their strategies for overcoming these barriers. Using elementary anthropological discourse analysis techniques, a process-based conceptual model of the parent experience was devised. The analysis revealed a parent-motivated model of barriers to care that enriched our understanding of quantitative findings regarding the population from which the focus group sample was drawn. Parent-identified barriers were grouped into the following six temporally and spatially sequenced categories: necessary skills and prerequisites for gaining access to the system; realizing access once it is gained; front office experiences; interactions with physicians; system arbitrariness and fragmentation; outcomes that affect future interaction with the system. Key to the successful navigation of the system was parents' functional biomedical acculturation; this construct likens the biomedical health services system to a cultural system within which all parents/patients must learn to function competently. Qualitative analysis of focus group data enabled a deeper understanding of barriers to care--one that went beyond the traditional association of marker variables with poor outcomes ("what") to reveal an understanding of the processes by which parents experience the health care system ("how,"why") and by which disparities may arise. Development of such process-oriented models furthers the provision of patient-centered care and the creation of interventions, programs, and curricula to enhance such care. Qualitative discourse analysis, for example using this project's widely applicable

  9. A spatial modeling approach to identify potential butternut restoration sites in Mammoth Cave National Park

    Science.gov (United States)

    Thompson, L.M.; Van Manen, F.T.; Schlarbaum, S.E.; DePoy, M.

    2006-01-01

    Incorporation of disease resistance is nearly complete for several important North American hardwood species threatened by exotic fungal diseases. The next important step toward species restoration would be to develop reliable tools to delineate ideal restoration sites on a landscape scale. We integrated spatial modeling and remote sensing techniques to delineate potential restoration sites for Butternut (Juglans cinerea L.) trees, a hardwood species being decimated by an exotic fungus, in Mammoth Cave National Park (MCNP), Kentucky. We first developed a multivariate habitat model to determine optimum Butternut habitats within MCNP. Habitat characteristics of 54 known Butternut locations were used in combination with eight topographic and land use data layers to calculate an index of habitat suitability based on Mahalanobis distance (D2). We used a bootstrapping technique to test the reliability of model predictions. Based on a threshold value for the D2 statistic, 75.9% of the Butternut locations were correctly classified, indicating that the habitat model performed well. Because Butternut seedlings require extensive amounts of sunlight to become established, we used canopy cover data to refine our delineation of favorable areas for Butternut restoration. Areas with the most favorable conditions to establish Butternut seedlings were limited to 291.6 ha. Our study provides a useful reference on the amount and location of favorable Butternut habitat in MCNP and can be used to identify priority areas for future Butternut restoration. Given the availability of relevant habitat layers and accurate location records, our approach can be applied to other tree species and areas. ?? 2006 Society for Ecological Restoration International.

  10. Ocean Heat and Carbon Uptake in Transient Climate Change: Identifying Model Uncertainty

    Science.gov (United States)

    Romanou, Anastasia; Marshall, John

    2015-01-01

    Global warming on decadal and centennial timescales is mediated and ameliorated by the oceansequestering heat and carbon into its interior. Transient climate change is a function of the efficiency by whichanthropogenic heat and carbon are transported away from the surface into the ocean interior (Hansen et al. 1985).Gregory and Mitchell (1997) and Raper et al. (2002) were the first to identify the importance of the ocean heat uptakeefficiency in transient climate change. Observational estimates (Schwartz 2012) and inferences from coupledatmosphere-ocean general circulation models (AOGCMs; Gregory and Forster 2008; Marotzke et al. 2015), suggest thatocean heat uptake efficiency on decadal timescales lies in the range 0.5-1.5 W/sq m/K and is thus comparable to theclimate feedback parameter (Murphy et al. 2009). Moreover, the ocean not only plays a key role in setting the timing ofwarming but also its regional patterns (Marshall et al. 2014), which is crucial to our understanding of regional climate,carbon and heat uptake, and sea-level change. This short communication is based on a presentation given by A.Romanou at a recent workshop, Oceans Carbon and Heat Uptake: Uncertainties and Metrics, co-hosted by US CLIVARand OCB. As briefly reviewed below, we have incomplete but growing knowledge of how ocean models used in climatechange projections sequester heat and carbon into the interior. To understand and thence reduce errors and biases inthe ocean component of coupled models, as well as elucidate the key mechanisms at work, in the final section we outlinea proposed model intercomparison project named FAFMIP. In FAFMIP, coupled integrations would be carried out withprescribed overrides of wind stress and freshwater and heat fluxes acting at the sea surface.

  11. A Flexible, Efficient Binomial Mixed Model for Identifying Differential DNA Methylation in Bisulfite Sequencing Data

    Science.gov (United States)

    Lea, Amanda J.

    2015-01-01

    Identifying sources of variation in DNA methylation levels is important for understanding gene regulation. Recently, bisulfite sequencing has become a popular tool for investigating DNA methylation levels. However, modeling bisulfite sequencing data is complicated by dramatic variation in coverage across sites and individual samples, and because of the computational challenges of controlling for genetic covariance in count data. To address these challenges, we present a binomial mixed model and an efficient, sampling-based algorithm (MACAU: Mixed model association for count data via data augmentation) for approximate parameter estimation and p-value computation. This framework allows us to simultaneously account for both the over-dispersed, count-based nature of bisulfite sequencing data, as well as genetic relatedness among individuals. Using simulations and two real data sets (whole genome bisulfite sequencing (WGBS) data from Arabidopsis thaliana and reduced representation bisulfite sequencing (RRBS) data from baboons), we show that our method provides well-calibrated test statistics in the presence of population structure. Further, it improves power to detect differentially methylated sites: in the RRBS data set, MACAU detected 1.6-fold more age-associated CpG sites than a beta-binomial model (the next best approach). Changes in these sites are consistent with known age-related shifts in DNA methylation levels, and are enriched near genes that are differentially expressed with age in the same population. Taken together, our results indicate that MACAU is an efficient, effective tool for analyzing bisulfite sequencing data, with particular salience to analyses of structured populations. MACAU is freely available at www.xzlab.org/software.html. PMID:26599596

  12. Inhibitors of Mycobacterium marinum virulence identified in a Dictyostelium discoideum host model.

    Directory of Open Access Journals (Sweden)

    Hajer Ouertatani-Sakouhi

    Full Text Available Tuberculosis remains one of the major threats to public health worldwide. Given the prevalence of multi drug resistance (MDR in Mycobacterium tuberculosis strains, there is a strong need to develop new anti-mycobacterial drugs with modes of action distinct from classical antibiotics. Inhibitors of mycobacterial virulence might target new molecular processes and may represent a potential new therapeutic alternative. In this study, we used a Dictyostelium discoideum host model to assess virulence of Mycobacterium marinum and to identify compounds inhibiting mycobacterial virulence. Among 9995 chemical compounds, we selected 12 inhibitors of mycobacterial virulence that do not inhibit mycobacterial growth in synthetic medium. Further analyses revealed that 8 of them perturbed functions requiring an intact mycobacterial cell wall such as sliding motility, bacterial aggregation or cell wall permeability. Chemical analogs of two compounds were analyzed. Chemical modifications altered concomitantly their effect on sliding motility and on mycobacterial virulence, suggesting that the alteration of the mycobacterial cell wall caused the loss of virulence. We characterized further one of the selected compounds and found that it inhibited the ability of mycobacteria to replicate in infected cells. Together these results identify new antimycobacterial compounds that represent new tools to unravel the molecular mechanisms controlling mycobacterial pathogenicity. The isolation of compounds with anti-virulence activity is the first step towards developing new antibacterial treatments.

  13. Testing job typologies and identifying at-risk subpopulations using factor mixture models.

    Science.gov (United States)

    Keller, Anita C; Igic, Ivana; Meier, Laurenz L; Semmer, Norbert K; Schaubroeck, John M; Brunner, Beatrice; Elfering, Achim

    2017-10-01

    Research in occupational health psychology has tended to focus on the effects of single job characteristics or various job characteristics combined into 1 factor. However, such a variable-centered approach does not account for the clustering of job attributes among groups of employees. We addressed this issue by using a person-centered approach to (a) investigate the occurrence of different empirical constellations of perceived job stressors and resources and (b) validate the meaningfulness of profiles by analyzing their association with employee well-being and performance. We applied factor mixture modeling to identify profiles in 4 large samples consisting of employees in Switzerland (Studies 1 and 2) and the United States (Studies 3 and 4). We identified 2 profiles that spanned the 4 samples, with 1 reflecting a combination of relatively low stressors and high resources (P1) and the other relatively high stressors and low resources (P3). The profiles differed mainly in terms of their organizational and social aspects. Employees in P1 reported significantly higher mean levels of job satisfaction, performance, and general health, and lower means in exhaustion compared with P3. Additional analyses showed differential relationships between job attributes and outcomes depending on profile membership. These findings may benefit organizational interventions as they show that perceived work stressors and resources more strongly influence satisfaction and well-being in particular profiles. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  14. A model-based approach for identifying signatures of ancient balancing selection in genetic data.

    Science.gov (United States)

    DeGiorgio, Michael; Lohmueller, Kirk E; Nielsen, Rasmus

    2014-08-01

    While much effort has focused on detecting positive and negative directional selection in the human genome, relatively little work has been devoted to balancing selection. This lack of attention is likely due to the paucity of sophisticated methods for identifying sites under balancing selection. Here we develop two composite likelihood ratio tests for detecting balancing selection. Using simulations, we show that these methods outperform competing methods under a variety of assumptions and demographic models. We apply the new methods to whole-genome human data, and find a number of previously-identified loci with strong evidence of balancing selection, including several HLA genes. Additionally, we find evidence for many novel candidates, the strongest of which is FANK1, an imprinted gene that suppresses apoptosis, is expressed during meiosis in males, and displays marginal signs of segregation distortion. We hypothesize that balancing selection acts on this locus to stabilize the segregation distortion and negative fitness effects of the distorter allele. Thus, our methods are able to reproduce many previously-hypothesized signals of balancing selection, as well as discover novel interesting candidates.

  15. A model-based approach for identifying signatures of ancient balancing selection in genetic data.

    Directory of Open Access Journals (Sweden)

    Michael DeGiorgio

    2014-08-01

    Full Text Available While much effort has focused on detecting positive and negative directional selection in the human genome, relatively little work has been devoted to balancing selection. This lack of attention is likely due to the paucity of sophisticated methods for identifying sites under balancing selection. Here we develop two composite likelihood ratio tests for detecting balancing selection. Using simulations, we show that these methods outperform competing methods under a variety of assumptions and demographic models. We apply the new methods to whole-genome human data, and find a number of previously-identified loci with strong evidence of balancing selection, including several HLA genes. Additionally, we find evidence for many novel candidates, the strongest of which is FANK1, an imprinted gene that suppresses apoptosis, is expressed during meiosis in males, and displays marginal signs of segregation distortion. We hypothesize that balancing selection acts on this locus to stabilize the segregation distortion and negative fitness effects of the distorter allele. Thus, our methods are able to reproduce many previously-hypothesized signals of balancing selection, as well as discover novel interesting candidates.

  16. Challenges of implementing collaborative models of decision making with trans-identified patients.

    Science.gov (United States)

    Dewey, Jodie M

    2015-10-01

    Factors health providers face during the doctor-patient encounter both impede and assist the development of collaborative models of treatment. I investigated decision making among medical and therapeutic professionals who work with trans-identified patients to understand factors that might impede or facilitate the adoption of the collaborative decision-making model in their clinical work. Following a grounded theory approach, I collected and analysed data from semi-structured interviews with 10 U.S. physicians and 10 U.S. mental health professionals. Doctors and therapists often desire collaboration with their patients but experience dilemmas in treating the trans-identified patients. Dilemmas include lack of formal education, little to no institutional support and inconsistent understanding and application of the main documents used by professionals treating trans-patients. Providers face considerable risk in providing unconventional treatments due to the lack of institutional and academic support relating to the treatment for trans-people, and the varied interpretation and application of the diagnostic and treatment documents used in treating trans-people. To address this risk, the relationship with the patient becomes crucial. However, trust, a component required for collaboration, is thwarted when the patients feel obliged to present in ways aligned with these documents in order to receive desired treatments. When trust cannot be established, medical and mental health providers can and do delay or deny treatments, resulting in the imbalance of power between patient and provider. The documents created to assist in treatment actually thwart professional desire to work collaboratively with patients. © 2013 John Wiley & Sons Ltd.

  17. Lifetime Traumatic Experiences and Leisure Physical Inactivity among Adolescent Boys.

    Science.gov (United States)

    Malinauskas, Romualdas; Malinauskiene, Vilija; Malinauskas, Mindaugas

    2018-03-01

    The aim of this study was to examine the associations between lifetime traumatic experiences and leisure physical inactivity among adolescent boys and to determine to what extent those associations are mediated by posttraumatic stress symptoms, unhealthy behaviors (smoking, alcohol use), the daily consumption of fresh fruit, and sense of coherence. A self-administered questionnaire combining 3 instruments measured leisure physical activity level (Godin and Shephard), symptoms of posttraumatic stress (IES-revised), lifetime traumatic experiences, sense of coherence (SOC-13, from Antonovsky), and behavioral and dietary patterns in a representative sample of eighth grade boys from a number of Kaunas, Lithuania, secondary schools (N = 885; response rate 88.6%). Fifty-six point eight percent of boys had experienced at least 1 lifetime traumatic event, with a 20.5% prevalence of PTS symptoms, and 5.4% were inactive during leisure time. In the logistic regression models, leisure physical inactivity was associated with lifetime traumatic experiences (adjusted OR = 2.33; 95% CI: 1.09-4.98). Sense of coherence and posttraumatic stress symptoms did not mediate those associations. Less-than-daily consumption of fresh fruit showed an independent effect, while smoking and weekly consumption of alcohol did not. Consistent associations between lifetime traumatic experiences and leisure physical inactivity among adolescent boys indicate that the presence of lifetime traumatic events should be taken into account when employing intervention and prevention programs on unhealthy lifestyles (physical inactivity, smoking, and alcohol).

  18. Regulatory activity based risk model identifies survival of stage II and III colorectal carcinoma.

    Science.gov (United States)

    Liu, Gang; Dong, Chuanpeng; Wang, Xing; Hou, Guojun; Zheng, Yu; Xu, Huilin; Zhan, Xiaohui; Liu, Lei

    2017-11-17

    Clinical and pathological indicators are inadequate for prognosis of stage II and III colorectal carcinoma (CRC). In this study, we utilized the activity of regulatory factors, univariate Cox regression and random forest for variable selection and developed a multivariate Cox model to predict the overall survival of Stage II/III colorectal carcinoma in GSE39582 datasets (469 samples). Patients in low-risk group showed a significant longer overall survival and recurrence-free survival time than those in high-risk group. This finding was further validated in five other independent datasets (GSE14333, GSE17536, GSE17537, GSE33113, and GSE37892). Besides, associations between clinicopathological information and risk score were analyzed. A nomogram including risk score was plotted to facilitate the utilization of risk score. The risk score model is also demonstrated to be effective on predicting both overall and recurrence-free survival of chemotherapy received patients. After performing Gene Set Enrichment Analysis (GSEA) between high and low risk groups, we found that several cell-cell interaction KEGG pathways were identified. Funnel plot results showed that there was no publication bias in these datasets. In summary, by utilizing the regulatory activity in stage II and III colorectal carcinoma, the risk score successfully predicts the survival of 1021 stage II/III CRC patients in six independent datasets.

  19. A preclinical model for identifying rats at risk of alcohol use disorder

    KAUST Repository

    Jadhav, Kshitij S.; Magistretti, Pierre J.; Halfon, Olivier; Augsburger, Marc; Boutrel, Benjamin

    2017-01-01

    Alcohol use is one of the world's leading causes of death and disease, although only a small proportion of individuals develop persistent alcohol use disorder (AUD). The identification of vulnerable individuals prior to their chronic intoxication remains of highest importance. We propose here to adapt current methodologies for identifying rats at risk of losing control over alcohol intake by modeling diagnostic criteria for AUD: Inability to abstain during a signaled period of reward unavailability, increased motivation assessed in a progressive effortful task and persistent alcohol intake despite aversive foot shocks. Factor analysis showed that these three addiction criteria loaded on one underlying construct indicating that they represent a latent construct of addiction trait. Further, not only vulnerable rats displayed higher ethanol consumption, and higher preference for ethanol over sweetened solutions, but they also exhibited pre-existing higher anxiety as compared to resilient rats. In conclusion, the present preclinical model confirms that development of an addiction trait not only requires prolonged exposure to alcohol, but also depends on endophenotype like anxiety that predispose a minority of individuals to lose control over alcohol consumption.

  20. A preclinical model for identifying rats at risk of alcohol use disorder

    KAUST Repository

    Jadhav, Kshitij S.

    2017-08-21

    Alcohol use is one of the world\\'s leading causes of death and disease, although only a small proportion of individuals develop persistent alcohol use disorder (AUD). The identification of vulnerable individuals prior to their chronic intoxication remains of highest importance. We propose here to adapt current methodologies for identifying rats at risk of losing control over alcohol intake by modeling diagnostic criteria for AUD: Inability to abstain during a signaled period of reward unavailability, increased motivation assessed in a progressive effortful task and persistent alcohol intake despite aversive foot shocks. Factor analysis showed that these three addiction criteria loaded on one underlying construct indicating that they represent a latent construct of addiction trait. Further, not only vulnerable rats displayed higher ethanol consumption, and higher preference for ethanol over sweetened solutions, but they also exhibited pre-existing higher anxiety as compared to resilient rats. In conclusion, the present preclinical model confirms that development of an addiction trait not only requires prolonged exposure to alcohol, but also depends on endophenotype like anxiety that predispose a minority of individuals to lose control over alcohol consumption.

  1. Predictive Modelling to Identify Near-Shore, Fine-Scale Seabird Distributions during the Breeding Season.

    Science.gov (United States)

    Warwick-Evans, Victoria C; Atkinson, Philip W; Robinson, Leonie A; Green, Jonathan A

    2016-01-01

    During the breeding season seabirds are constrained to coastal areas and are restricted in their movements, spending much of their time in near-shore waters either loafing or foraging. However, in using these areas they may be threatened by anthropogenic activities such as fishing, watersports and coastal developments including marine renewable energy installations. Although many studies describe large scale interactions between seabirds and the environment, the drivers behind near-shore, fine-scale distributions are not well understood. For example, Alderney is an important breeding ground for many species of seabird and has a diversity of human uses of the marine environment, thus providing an ideal location to investigate the near-shore fine-scale interactions between seabirds and the environment. We used vantage point observations of seabird distribution, collected during the 2013 breeding season in order to identify and quantify some of the environmental variables affecting the near-shore, fine-scale distribution of seabirds in Alderney's coastal waters. We validate the models with observation data collected in 2014 and show that water depth, distance to the intertidal zone, and distance to the nearest seabird nest are key predictors in the distribution of Alderney's seabirds. AUC values for each species suggest that these models perform well, although the model for shags performed better than those for auks and gulls. While further unexplained underlying localised variation in the environmental conditions will undoubtedly effect the fine-scale distribution of seabirds in near-shore waters we demonstrate the potential of this approach in marine planning and decision making.

  2. Predictive Modelling to Identify Near-Shore, Fine-Scale Seabird Distributions during the Breeding Season.

    Directory of Open Access Journals (Sweden)

    Victoria C Warwick-Evans

    Full Text Available During the breeding season seabirds are constrained to coastal areas and are restricted in their movements, spending much of their time in near-shore waters either loafing or foraging. However, in using these areas they may be threatened by anthropogenic activities such as fishing, watersports and coastal developments including marine renewable energy installations. Although many studies describe large scale interactions between seabirds and the environment, the drivers behind near-shore, fine-scale distributions are not well understood. For example, Alderney is an important breeding ground for many species of seabird and has a diversity of human uses of the marine environment, thus providing an ideal location to investigate the near-shore fine-scale interactions between seabirds and the environment. We used vantage point observations of seabird distribution, collected during the 2013 breeding season in order to identify and quantify some of the environmental variables affecting the near-shore, fine-scale distribution of seabirds in Alderney's coastal waters. We validate the models with observation data collected in 2014 and show that water depth, distance to the intertidal zone, and distance to the nearest seabird nest are key predictors in the distribution of Alderney's seabirds. AUC values for each species suggest that these models perform well, although the model for shags performed better than those for auks and gulls. While further unexplained underlying localised variation in the environmental conditions will undoubtedly effect the fine-scale distribution of seabirds in near-shore waters we demonstrate the potential of this approach in marine planning and decision making.

  3. Novel modeling of combinatorial miRNA targeting identifies SNP with potential role in bone density.

    Directory of Open Access Journals (Sweden)

    Claudia Coronnello

    Full Text Available MicroRNAs (miRNAs are post-transcriptional regulators that bind to their target mRNAs through base complementarity. Predicting miRNA targets is a challenging task and various studies showed that existing algorithms suffer from high number of false predictions and low to moderate overlap in their predictions. Until recently, very few algorithms considered the dynamic nature of the interactions, including the effect of less specific interactions, the miRNA expression level, and the effect of combinatorial miRNA binding. Addressing these issues can result in a more accurate miRNA:mRNA modeling with many applications, including efficient miRNA-related SNP evaluation. We present a novel thermodynamic model based on the Fermi-Dirac equation that incorporates miRNA expression in the prediction of target occupancy and we show that it improves the performance of two popular single miRNA target finders. Modeling combinatorial miRNA targeting is a natural extension of this model. Two other algorithms show improved prediction efficiency when combinatorial binding models were considered. ComiR (Combinatorial miRNA targeting, a novel algorithm we developed, incorporates the improved predictions of the four target finders into a single probabilistic score using ensemble learning. Combining target scores of multiple miRNAs using ComiR improves predictions over the naïve method for target combination. ComiR scoring scheme can be used for identification of SNPs affecting miRNA binding. As proof of principle, ComiR identified rs17737058 as disruptive to the miR-488-5p:NCOA1 interaction, which we confirmed in vitro. We also found rs17737058 to be significantly associated with decreased bone mineral density (BMD in two independent cohorts indicating that the miR-488-5p/NCOA1 regulatory axis is likely critical in maintaining BMD in women. With increasing availability of comprehensive high-throughput datasets from patients ComiR is expected to become an essential

  4. Bright boys the making of information technology

    CERN Document Server

    Green, Tom

    2010-01-01

    Everything has a beginning. None was more profound-and quite as unexpected-than Information Technology. Here for the first time is the untold story of how our new age came to be and the bright boys who made it happen. What began on the bare floor of an old laundry building eventually grew to rival in size the Manhattan Project. The unexpected consequence of that journey was huge---what we now know as Information Technology. For sixty years the bright boys have been totally anonymous while their achievements have become a way of life for all of us. "Bright Boys" brings them home. By 1950 they'd

  5. Identifying autism early: The Toddlers at Risk of Autism Clinic model.

    Science.gov (United States)

    Davis, Tessa; Clifton, Deirdre; Papadopoulos, Con

    2015-07-01

    This paper describes the Toddlers at Risk of Autism Clinic (TRAC), which utilises the Social Attention and Communication Study (SACS) and/or Autism Detection in Early Childhood (ADEC) play-based assessments to facilitate the early diagnosis of autism. A retrospective audit was conducted of all 42 children assessed over a 3-year period in the TRAC. A semi-structured interview and play-based assessment (SACS and ADEC) were used to aid experienced clinicians in diagnosing autism. Intervention was recommended, and families were routinely followed up. Analysis was conducted on the tools used, the outcomes of assessment, diagnosis and stability of diagnosis on follow-up. During this period, 35 boys and 7 girls were assessed, with a mean age of 25 months. The average waiting time for clinic was 11.6 weeks. Twenty-five patients were diagnosed with autism; 90.5% of toddlers given an initial diagnosis retained that diagnosis at follow-up. Out of the 17 children who were not diagnosed with autism in the TRAC, one child was later diagnosed with autism. Experienced clinicians can use the SACS and/or ADEC to assist with a Diagnostic and Statistical Manual diagnosis of autism in toddlers. © 2015 The Authors. Journal of Paediatrics and Child Health © 2015 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  6. Full field optical coherence tomography can identify spermatogenesis in a rodent sertoli-cell only model.

    Science.gov (United States)

    Ramasamy, Ranjith; Sterling, Joshua; Manzoor, Maryem; Salamoon, Bekheit; Jain, Manu; Fisher, Erik; Li, Phillip S; Schlegel, Peter N; Mukherjee, Sushmita

    2012-01-01

    Microdissection testicular sperm extraction (micro-TESE) has replaced conventional testis biopsies as a method of choice for obtaining sperm for in vitro fertilization for men with nonobstructive azoospermia. A technical challenge of micro-TESE is that the low magnification inspection of the tubules with a surgical microscope is insufficient to definitively identify sperm-containing tubules, necessitating tissue removal and cytologic assessment. Full field optical coherence tomography (FFOCT) uses white light interference microscopy to generate quick high-resolution tomographic images of fresh (unprocessed and unstained) tissue. Furthermore, by using a nonlaser safe light source (150 W halogen lamp) for tissue illumination, it ensures that the sperm extracted for in vitro fertilization are not photo-damaged or mutagenized. A focal Sertoli-cell only rodent model was created with busulfan injection in adult rats. Ex vivo testicular tissues from both normal and busulfan-treated rats were imaged with a commercial modified FFOCT system, Light-CT™, and the images were correlated with gold standard hematoxylin and eosin staining. Light-CT™ identified spermatogenesis within the seminiferous tubules in freshly excised testicular tissue, without the use of exogenous contrast or fixation. Normal adult rats exhibited tubules with uniform size and shape (diameter 328 ±11 μm). The busulfan-treated animals showed marked heterogeneity in tubular size and shape (diameter 178 ± 35 μm) and only 10% contained sperm within the lumen. FFOCT has the potential to facilitate real-time visualization of spermatogenesis in humans, and aid in micro-TESE for men with infertility.

  7. Identifying co-targets to fight drug resistance based on a random walk model

    Directory of Open Access Journals (Sweden)

    Chen Liang-Chun

    2012-01-01

    Full Text Available Abstract Background Drug resistance has now posed more severe and emergent threats to human health and infectious disease treatment. However, wet-lab approaches alone to counter drug resistance have so far still achieved limited success due to less knowledge about the underlying mechanisms of drug resistance. Our approach apply a heuristic search algorithm in order to extract active network under drug treatment and use a random walk model to identify potential co-targets for effective antibacterial drugs. Results We use interactome network of Mycobacterium tuberculosis and gene expression data which are treated with two kinds of antibiotic, Isoniazid and Ethionamide as our test data. Our analysis shows that the active drug-treated networks are associated with the trigger of fatty acid metabolism and synthesis and nicotinamide adenine dinucleotide (NADH-related processes and those results are consistent with the recent experimental findings. Efflux pumps processes appear to be the major mechanisms of resistance but SOS response is significantly up-regulation under Isoniazid treatment. We also successfully identify the potential co-targets with literature confirmed evidences which are related to the glycine-rich membrane, adenosine triphosphate energy and cell wall processes. Conclusions With gene expression and interactome data supported, our study points out possible pathways leading to the emergence of drug resistance under drug treatment. We develop a computational workflow for giving new insights to bacterial drug resistance which can be gained by a systematic and global analysis of the bacterial regulation network. Our study also discovers the potential co-targets with good properties in biological and graph theory aspects to overcome the problem of drug resistance.

  8. Behavioural patterns of conflict resolution strategies in preschool boys with language impairment in comparison with boys with typical language development.

    Science.gov (United States)

    Horowitz, Laura; Jansson, Liselotte; Ljungberg, Tomas; Hedenbro, Monica

    2005-01-01

    Children with language impairment (LI) experience social difficulties, including conflict management. This paper is therefore motivated to examine behavioural processes guiding preschool peer conflict progression, which ultimately contributes to overall development. To describe behavioural sequences in conflicts between children with typically developing language (TL) and between children with LI. Attention is particularly focused on the conflict resolution strategy reconciliation, i.e. friendly contact between former opponents shortly following conflict termination. It is hypothesized that children with LI, with weaker language skills, experience difficulties attaining effective reconciliation. Unstructured play of 11 boys with LI (4-7-years-old), at a specialized language preschool, and 20 TL boys (4-6-years-old), at mainstream preschools, were video filmed. Conflicts were identified and recorded according to a validated coding system. Recorded conflict details included behavioural sequences constituting conflict cause (conflict period) and in the post-conflict period, reconciliatory behaviours that were classified into six 'categories' (Invitation to play, Body contact, Object offer, Verbal apology, Self-ridicule, Cognition, i.e. offering privileges/negotiating) and the verbal character of accepted behaviours were determined. The mean proportion of individual target children's conflicts in which specific behavioural sequences had occurred were calculated and thereafter compared between and within the groups. Boys with LI reconcile fewer conflicts than TL boys (LI: 47.3 +/- 4.5%; TL: 63.6 +/- 2.0%). Contributory factors include the occurrence of conflicts caused by aberrance, i.e. conflicts initiated by inappropriate behavioural play intensities (i.e. 'a pillow fight' where one partner swings so intensively the other partner cannot participate as a player in the game) and protests that are no longer directed to the opponent within reciprocal exchanges, but

  9. Probing molecular mechanisms of the Hsp90 chaperone: biophysical modeling identifies key regulators of functional dynamics.

    Directory of Open Access Journals (Sweden)

    Anshuman Dixit

    Full Text Available Deciphering functional mechanisms of the Hsp90 chaperone machinery is an important objective in cancer biology aiming to facilitate discovery of targeted anti-cancer therapies. Despite significant advances in understanding structure and function of molecular chaperones, organizing molecular principles that control the relationship between conformational diversity and functional mechanisms of the Hsp90 activity lack a sufficient quantitative characterization. We combined molecular dynamics simulations, principal component analysis, the energy landscape model and structure-functional analysis of Hsp90 regulatory interactions to systematically investigate functional dynamics of the molecular chaperone. This approach has identified a network of conserved regions common to the Hsp90 chaperones that could play a universal role in coordinating functional dynamics, principal collective motions and allosteric signaling of Hsp90. We have found that these functional motifs may be utilized by the molecular chaperone machinery to act collectively as central regulators of Hsp90 dynamics and activity, including the inter-domain communications, control of ATP hydrolysis, and protein client binding. These findings have provided support to a long-standing assertion that allosteric regulation and catalysis may have emerged via common evolutionary routes. The interaction networks regulating functional motions of Hsp90 may be determined by the inherent structural architecture of the molecular chaperone. At the same time, the thermodynamics-based "conformational selection" of functional states is likely to be activated based on the nature of the binding partner. This mechanistic model of Hsp90 dynamics and function is consistent with the notion that allosteric networks orchestrating cooperative protein motions can be formed by evolutionary conserved and sparsely connected residue clusters. Hence, allosteric signaling through a small network of distantly connected

  10. Are boys discriminated in Swedish high schools?

    DEFF Research Database (Denmark)

    Hinnerich, Bjørn Tyrefors; Höglin, Erik; Johannesson, Magnus

    2011-01-01

    Girls typically have higher grades than boys in school and recent research suggests that part of this gender difference may be due to discrimination of boys in grading.Werigorously test this in a field experiment where a random sample of the same tests in the Swedish language is subject to blind...... and non-blind grading. The non-blind test score is on average 15% lower for boys than for girls. Blind grading lowers the average grades with 13%, indicating that personal ties and/or grade inflation are important in non-blind grading. But we find no evidence of discrimination against boys in grading....... The point estimate of the discrimination effect is close to zero with a 95% confidence interval of±4.5% of the average non-blind grade....

  11. Minimizing embarrassment: boys' experiences of pubertal changes.

    Science.gov (United States)

    Flaming, D; Morse, J M

    1991-01-01

    As very little is known about boys' subjective and emotional experiences when going through puberty, the qualitative research method of grounded theory was used in this study to address the question: "What is the experience of the physical maturational changes in male adolescents?" A Basic Social Psychological Process emerged, Minimizing Embarrassment, with four stages: waiting for the change, noticing the change, dealing with the change, and feeling comfortable with the change. Boys developed expectations from listening to others, by looking at older males, and by wondering and imagining what the changes would eventually be like for them. After developing these expectations, they compared their physical changes to others and to their own expectations. If the boys felt they were different from their peers, they worried about this difference. They used strategies such as avoiding, pretending, and joking to avoid embarrassment or to deal with embarrassing situations. If the boys felt they were "normal," they accepted the fact that they were maturing properly.

  12. Boys' boarding school management: understanding the choice ...

    African Journals Online (AJOL)

    Maggard,. 1976). Kotler ... positioning strategy for a secondary boys' boarding school should seek to match its .... (in this case, the attributes parents consider important in boarding school selection), ..... Marketing for Hospitality and Tourism (3rd ed).

  13. Serotonergic contribution to boys' behavioral regulation.

    Directory of Open Access Journals (Sweden)

    Amélie Nantel-Vivier

    Full Text Available Animal and human adult studies reveal a contribution of serotonin to behavior regulation. Whether these findings apply to children is unclear. The present study investigated serotonergic functioning in boys with a history of behavior regulation difficulties through a double-blind, acute tryptophan supplementation procedure.Participants were 23 boys (age 10 years with a history of elevated physical aggression, recruited from a community sample. Eleven were given a chocolate milkshake supplemented with 500 mg tryptophan, and 12 received a chocolate milkshake without tryptophan. Boys engaged in a competitive reaction time game against a fictitious opponent, which assessed response to provocation, impulsivity, perspective taking, and sharing. Impulsivity was further assessed through a Go/No-Go paradigm. A computerized emotion recognition task and a staged instrumental help incident were also administered.Boys, regardless of group, responded similarly to high provocation by the fictitious opponent. However, boys in the tryptophan group adjusted their level of responding optimally as a function of the level of provocation, whereas boys in the control group significantly decreased their level of responding towards the end of the competition. Boys in the tryptophan group tended to show greater perspective taking, tended to better distinguish facial expressions of fear and happiness, and tended to provide greater instrumental help to the experimenter.The present study provides initial evidence for the feasibility of acute tryptophan supplementation in children and some effect of tryptophan supplementation on children's behaviors. Further studies are warranted to explore the potential impact of increased serotonergic functioning on boys' dominant and affiliative behaviors.

  14. Little Boy replication: justification and construction

    International Nuclear Information System (INIS)

    Malenfant, R.E.

    1984-01-01

    A reconstruction of the Little Boy weapon allowed experiments to evaluate yield, leakage measurements for comparison with calculations, and phenomenological measurements to evaluate various in-situ dosimeters. The reconstructed weapon was operated at sustained delayed critical at the Los Alamos Critical Assembly Facility. The present experiments provide a wealth of information to benchmark calculations and demonstrate that the 1965 measurements on the Ichiban assembly (a spherical mockup of Little Boy) were in error. 5 references, 2 figures

  15. Little Boy replication: justification and construction

    International Nuclear Information System (INIS)

    Malenfant, R.E.

    1984-01-01

    A reconstruction of the Little Boy weapon allowed experiments to evaluate yield, leakage measurements for comparison with calculations, and phenomenological measurements to evaluate various in-situ dosimeters. The reconstructed weapon was operated at sustained delayed critical at the Los Alamos Critical Assembly Facility. The present experiments provide a wealth of information to benchmark calculations and demonstrate that the 1965 measurements on the Ichiban assembly (a spherical mockup of Little Boy) were in error

  16. Using language models to identify relevant new information in inpatient clinical notes.

    Science.gov (United States)

    Zhang, Rui; Pakhomov, Serguei V; Lee, Janet T; Melton, Genevieve B

    2014-01-01

    Redundant information in clinical notes within electronic health record (EHR) systems is ubiquitous and may negatively impact the use of these notes by clinicians, and, potentially, the efficiency of patient care delivery. Automated methods to identify redundant versus relevant new information may provide a valuable tool for clinicians to better synthesize patient information and navigate to clinically important details. In this study, we investigated the use of language models for identification of new information in inpatient notes, and evaluated our methods using expert-derived reference standards. The best method achieved precision of 0.743, recall of 0.832 and F1-measure of 0.784. The average proportion of redundant information was similar between inpatient and outpatient progress notes (76.6% (SD=17.3%) and 76.7% (SD=14.0%), respectively). Advanced practice providers tended to have higher rates of redundancy in their notes compared to physicians. Future investigation includes the addition of semantic components and visualization of new information.

  17. Identifying bubble collapse in a hydrothermal system using hidden Markov models

    Science.gov (United States)

    Dawson, P.B.; Benitez, M.C.; Lowenstern, J. B.; Chouet, B.A.

    2012-01-01

    Beginning in July 2003 and lasting through September 2003, the Norris Geyser Basin in Yellowstone National Park exhibited an unusual increase in ground temperature and hydrothermal activity. Using hidden Markov model theory, we identify over five million high-frequency (>15Hz) seismic events observed at a temporary seismic station deployed in the basin in response to the increase in hydrothermal activity. The source of these seismic events is constrained to within ???100 m of the station, and produced ???3500-5500 events per hour with mean durations of ???0.35-0.45s. The seismic event rate, air temperature, hydrologic temperatures, and surficial water flow of the geyser basin exhibited a marked diurnal pattern that was closely associated with solar thermal radiance. We interpret the source of the seismicity to be due to the collapse of small steam bubbles in the hydrothermal system, with the rate of collapse being controlled by surficial temperatures and daytime evaporation rates. copyright 2012 by the American Geophysical Union.

  18. Sensitivity analysis of the STICS-MACRO model to identify cropping practices reducing pesticides losses.

    Science.gov (United States)

    Lammoglia, Sabine-Karen; Makowski, David; Moeys, Julien; Justes, Eric; Barriuso, Enrique; Mamy, Laure

    2017-02-15

    STICS-MACRO is a process-based model simulating the fate of pesticides in the soil-plant system as a function of agricultural practices and pedoclimatic conditions. The objective of this work was to evaluate the influence of crop management practices on water and pesticide flows in contrasted environmental conditions. We used the Morris screening sensitivity analysis method to identify the most influential cropping practices. Crop residues management and tillage practices were shown to have strong effects on water percolation and pesticide leaching. In particular, the amount of organic residues added to soil was found to be the most influential input. The presence of a mulch could increase soil water content so water percolation and pesticide leaching. Conventional tillage was also found to decrease pesticide leaching, compared to no-till, which is consistent with many field observations. The effects of the soil, crop and climate conditions tested in this work were less important than those of cropping practices. STICS-MACRO allows an ex ante evaluation of cropping systems and agricultural practices, and of the related pesticides environmental impacts. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Model for selecting quality standards for a salad bar through identifying elements of customer satisfaction.

    Science.gov (United States)

    Ouellet, D; Norback, J P

    1993-11-01

    Continuous quality improvement is the new requirement of the Joint Commission on Accreditation of Healthcare Organizations. This means that meeting quality standards will not be enough. Dietitians will need to improve those standards and the way they are selected. Because quality is defined in terms of the customers, all quality improvement projects must start by defining what customers want. Using a salad bar as an example, this article presents and illustrates a technique developed in Japan to identify which elements in a product or service will satisfy or dissatisfy consumers. Using a model and a questionnaire format developed by Kano and coworkers, 273 students were surveyed to classify six quality elements of a salad bar. Four elements showed a dominant "must-be" characteristic: food freshness, labeling of the dressings, no spills in the food, and no spills on the salad bar. The two other elements (food easy to reach and food variety) showed a dominant one-dimensional characteristic. By better understanding consumer perceptions of quality elements, foodservice managers can select quality standards that focus on what really matters to their consumers.

  20. A mouse model of hereditary coproporphyria identified in an ENU mutagenesis screen

    Directory of Open Access Journals (Sweden)

    Ashlee J. Conway

    2017-08-01

    Full Text Available A genome-wide ethyl-N-nitrosourea (ENU mutagenesis screen in mice was performed to identify novel regulators of erythropoiesis. Here, we describe a mouse line, RBC16, which harbours a dominantly inherited mutation in the Cpox gene, responsible for production of the haem biosynthesis enzyme, coproporphyrinogen III oxidase (CPOX. A premature stop codon in place of a tryptophan at amino acid 373 results in reduced mRNA expression and diminished protein levels, yielding a microcytic red blood cell phenotype in heterozygous mice. Urinary and faecal porphyrins in female RBC16 heterozygotes were significantly elevated compared with that of wild-type littermates, particularly coproporphyrinogen III, whereas males were biochemically normal. Attempts to induce acute porphyric crises were made using fasting and phenobarbital treatment on females. While fasting had no biochemical effect on RBC16 mice, phenobarbital caused significant elevation of faecal coproporphyrinogen III in heterozygous mice. This is the first known investigation of a mutagenesis mouse model with genetic and biochemical parallels to hereditary coproporphyria.

  1. Novel expressed sequences identified in a model of androgen independent prostate cancer

    Directory of Open Access Journals (Sweden)

    Jones Steven JM

    2007-01-01

    Full Text Available Abstract Background Prostate cancer is the most frequently diagnosed cancer in American men, and few effective treatment options are available to patients who develop hormone-refractory prostate cancer. The molecular changes that occur to allow prostate cells to proliferate in the absence of androgens are not fully understood. Results Subtractive hybridization experiments performed with samples from an in vivo model of hormonal progression identified 25 expressed sequences representing novel human transcripts. Intriguingly, these 25 sequences have small open-reading frames and are not highly conserved through evolution, suggesting many of these novel expressed sequences may be derived from untranslated regions of novel transcripts or from non-coding transcripts. Examination of a large metalibrary of human Serial Analysis of Gene Expression (SAGE tags demonstrated that only three of these novel sequences had been previously detected. RT-PCR experiments confirmed that the 6 sequences tested were expressed in specific human tissues, as well as in clinical samples of prostate cancer. Further RT-PCR experiments for five of these fragments indicated they originated from large untranslated regions of unannotated transcripts. Conclusion This study underlines the value of using complementary techniques in the annotation of the human genome. The tissue-specific expression of 4 of the 6 clones tested indicates the expression of these novel transcripts is tightly regulated, and future work will determine the possible role(s these novel transcripts may play in the progression of prostate cancer.

  2. Identifying overrepresented concepts in gene lists from literature: a statistical approach based on Poisson mixture model

    Directory of Open Access Journals (Sweden)

    Zhai Chengxiang

    2010-05-01

    Full Text Available Abstract Background Large-scale genomic studies often identify large gene lists, for example, the genes sharing the same expression patterns. The interpretation of these gene lists is generally achieved by extracting concepts overrepresented in the gene lists. This analysis often depends on manual annotation of genes based on controlled vocabularies, in particular, Gene Ontology (GO. However, the annotation of genes is a labor-intensive process; and the vocabularies are generally incomplete, leaving some important biological domains inadequately covered. Results We propose a statistical method that uses the primary literature, i.e. free-text, as the source to perform overrepresentation analysis. The method is based on a statistical framework of mixture model and addresses the methodological flaws in several existing programs. We implemented this method within a literature mining system, BeeSpace, taking advantage of its analysis environment and added features that facilitate the interactive analysis of gene sets. Through experimentation with several datasets, we showed that our program can effectively summarize the important conceptual themes of large gene sets, even when traditional GO-based analysis does not yield informative results. Conclusions We conclude that the current work will provide biologists with a tool that effectively complements the existing ones for overrepresentation analysis from genomic experiments. Our program, Genelist Analyzer, is freely available at: http://workerbee.igb.uiuc.edu:8080/BeeSpace/Search.jsp

  3. “I Am Happy that God Made Me a Boy”: Zambian Adolescent Boys ...

    African Journals Online (AJOL)

    ... adolescent boys\\' perceptions, norms, role models and gender relations that ... we recommend that the information gap, misconceptions and anxiety among ... The respondents suggested that an educational programme that will pay due ...

  4. Using multi-state markov models to identify credit card risk

    Directory of Open Access Journals (Sweden)

    Daniel Evangelista Régis

    2016-06-01

    Full Text Available Abstract The main interest of this work is to analyze the application of multi-state Markov models to evaluate credit card risk by investigating the characteristics of different state transitions in client-institution relationships over time, thereby generating score models for various purposes. We also used logistic regression models to compare the results with those obtained using multi-state Markov models. The models were applied to an actual database of a Brazilian financial institution. In this application, multi-state Markov models performed better than logistic regression models in predicting default risk, and logistic regression models performed better in predicting cancellation risk.

  5. An uncertainty inclusive un-mixing model to identify tracer non-conservativeness

    Science.gov (United States)

    Sherriff, Sophie; Rowan, John; Franks, Stewart; Fenton, Owen; Jordan, Phil; hUallacháin, Daire Ó.

    2015-04-01

    sensitive screening technique than assessing target values against source data. Non-conservative behaviour was identified in field data however only at a significant degree of corruption. Whilst further testing is required to determine the impact of individual and combined uncertainty components on synthetic, controlled experiments and field data, this study provides a framework for future assessment of uncertainty in un-mixing models.

  6. Simultaneous Video-EEG-ECG Monitoring to Identify Neurocardiac Dysfunction in Mouse Models of Epilepsy.

    Science.gov (United States)

    Mishra, Vikas; Gautier, Nicole M; Glasscock, Edward

    2018-01-29

    In epilepsy, seizures can evoke cardiac rhythm disturbances such as heart rate changes, conduction blocks, asystoles, and arrhythmias, which can potentially increase risk of sudden unexpected death in epilepsy (SUDEP). Electroencephalography (EEG) and electrocardiography (ECG) are widely used clinical diagnostic tools to monitor for abnormal brain and cardiac rhythms in patients. Here, a technique to simultaneously record video, EEG, and ECG in mice to measure behavior, brain, and cardiac activities, respectively, is described. The technique described herein utilizes a tethered (i.e., wired) recording configuration in which the implanted electrode on the head of the mouse is hard-wired to the recording equipment. Compared to wireless telemetry recording systems, the tethered arrangement possesses several technical advantages such as a greater possible number of channels for recording EEG or other biopotentials; lower electrode costs; and greater frequency bandwidth (i.e., sampling rate) of recordings. The basics of this technique can also be easily modified to accommodate recording other biosignals, such as electromyography (EMG) or plethysmography for assessment of muscle and respiratory activity, respectively. In addition to describing how to perform the EEG-ECG recordings, we also detail methods to quantify the resulting data for seizures, EEG spectral power, cardiac function, and heart rate variability, which we demonstrate in an example experiment using a mouse with epilepsy due to Kcna1 gene deletion. Video-EEG-ECG monitoring in mouse models of epilepsy or other neurological disease provides a powerful tool to identify dysfunction at the level of the brain, heart, or brain-heart interactions.

  7. Identifying Future Training Technology Opportunities Using Career Field Models and Simulations

    National Research Council Canada - National Science Library

    Bennett, Jr., Winston; Stone, Brice; Turner, Kathryn; Ruck, Hendrick W

    2002-01-01

    ... itself. This report presents results from a recent application of a career field education and training planning simulation capability to identify cost-effective opportunities for the introduction...

  8. Evaluation of current prediction models for Lynch syndrome: updating the PREMM5 model to identify PMS2 mutation carriers.

    Science.gov (United States)

    Goverde, A; Spaander, M C W; Nieboer, D; van den Ouweland, A M W; Dinjens, W N M; Dubbink, H J; Tops, C J; Ten Broeke, S W; Bruno, M J; Hofstra, R M W; Steyerberg, E W; Wagner, A

    2018-07-01

    Until recently, no prediction models for Lynch syndrome (LS) had been validated for PMS2 mutation carriers. We aimed to evaluate MMRpredict and PREMM5 in a clinical cohort and for PMS2 mutation carriers specifically. In a retrospective, clinic-based cohort we calculated predictions for LS according to MMRpredict and PREMM5. The area under the operator receiving characteristic curve (AUC) was compared between MMRpredict and PREMM5 for LS patients in general and for different LS genes specifically. Of 734 index patients, 83 (11%) were diagnosed with LS; 23 MLH1, 17 MSH2, 31 MSH6 and 12 PMS2 mutation carriers. Both prediction models performed well for MLH1 and MSH2 (AUC 0.80 and 0.83 for PREMM5 and 0.79 for MMRpredict) and fair for MSH6 mutation carriers (0.69 for PREMM5 and 0.66 for MMRpredict). MMRpredict performed fair for PMS2 mutation carriers (AUC 0.72), while PREMM5 failed to discriminate PMS2 mutation carriers from non-mutation carriers (AUC 0.51). The only statistically significant difference between PMS2 mutation carriers and non-mutation carriers was proximal location of colorectal cancer (77 vs. 28%, p PMS2 mutation carriers (AUC 0.77) and overall (AUC 0.81 vs. 0.72). We validated these results in an external cohort of 376 colorectal cancer patients, including 158 LS patients. MMRpredict and PREMM5 cannot adequately identify PMS2 mutation carriers. Adding location of colorectal cancer to PREMM5 may improve the performance of this model, which should be validated in larger cohorts.

  9. Specification Search for Identifying the Correct Mean Trajectory in Polynomial Latent Growth Models

    Science.gov (United States)

    Kim, Minjung; Kwok, Oi-Man; Yoon, Myeongsun; Willson, Victor; Lai, Mark H. C.

    2016-01-01

    This study investigated the optimal strategy for model specification search under the latent growth modeling (LGM) framework, specifically on searching for the correct polynomial mean or average growth model when there is no a priori hypothesized model in the absence of theory. In this simulation study, the effectiveness of different starting…

  10. Study of Psycho-Social Factors Affecting Traffic Accidents Among Young Boys in Tehran.

    Science.gov (United States)

    Javadi, Seyyed Mohammad Hossein; Fekr Azad, Hossein; Tahmasebi, Siyamak; Rafiei, Hassan; Rahgozar, Mehdi; Tajlili, Alireza

    2015-07-01

    Unprecedented growth of fatalities due to traffic accidents in the recent years has raised great concerns and efforts of authorities in order to identify and control the causes of these accidents. In the present study, the contribution of psychological, social, demographic, environmental and behavioral factors on traffic accidents was studied for young boys in Tehran, emphasizing the importance of psychosocial factors. The design of the present study was quantitative (correlational) in which a sample population including 253 boys from Tehran (Iran) with an age range of 18 to 24 who had been referred to insurance institutions, hospitals, correctional facilities as well as prisons, were selected using stratified cluster sampling during the year 2013.The subjects completed the following questionnaires: demographic, general health, lifestyle, Manchester Driving Behavior Questionnaire (MDBQ), young parenting, and NEO-Five Factor Inventory (NEO-FFI). For data analysis, descriptive statistics, correlation coefficient, and inferential statistics including simultaneous regression, stepwise regression, and structural equations modeling were used. The findings indicated that in the psychosocial model of driving behavior (including lapses, mistakes, and intentional violations) and accidents, psychological factors, depression (P scope of these factors links accidents to other social issues and damages.

  11. Identifying students’ mental models of sound propagation: The role of conceptual blending in understanding conceptual change

    Directory of Open Access Journals (Sweden)

    Zdeslav Hrepic

    2010-09-01

    Full Text Available We investigated introductory physics students’ mental models of sound propagation. We used a phenomenographic method to analyze the data in the study. In addition to the scientifically accepted Wave model, students used the “Entity” model to describe the propagation of sound. In this latter model sound is a self-standing entity, different from the medium through which it propagates. All other observed alternative models contain elements of both Entity and Wave models, but at the same time are distinct from each of the constituent models. We called these models “hybrid” or “blend” models. We discuss how students use these models in various contexts before and after instruction and how our findings contribute to the understanding of conceptual change. Implications of our findings for teaching are summarized.

  12. Finding identifiable parameter combinations in nonlinear ODE models and the rational reparameterization of their input-output equations.

    Science.gov (United States)

    Meshkat, Nicolette; Anderson, Chris; Distefano, Joseph J

    2011-09-01

    When examining the structural identifiability properties of dynamic system models, some parameters can take on an infinite number of values and yet yield identical input-output data. These parameters and the model are then said to be unidentifiable. Finding identifiable combinations of parameters with which to reparameterize the model provides a means for quantitatively analyzing the model and computing solutions in terms of the combinations. In this paper, we revisit and explore the properties of an algorithm for finding identifiable parameter combinations using Gröbner Bases and prove useful theoretical properties of these parameter combinations. We prove a set of M algebraically independent identifiable parameter combinations can be found using this algorithm and that there exists a unique rational reparameterization of the input-output equations over these parameter combinations. We also demonstrate application of the procedure to a nonlinear biomodel. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Identifying Student and Teacher Difficulties in Interpreting Atomic Spectra Using a Quantum Model of Emission and Absorption of Radiation

    Science.gov (United States)

    Savall-Alemany, Francisco; Domènech-Blanco, Josep Lluís; Guisasola, Jenaro; Martínez-Torregrosa, Joaquín

    2016-01-01

    Our study sets out to identify the difficulties that high school students, teachers, and university students encounter when trying to explain atomic spectra. To do so, we identify the key concepts that any quantum model for the emission and absorption of electromagnetic radiation must include to account for the gas spectra and we then design two…

  14. Why Should Secondary Schools Take Working with Boys Seriously?

    Science.gov (United States)

    Jackson, David; Salisbury, Jonathan

    1996-01-01

    Addresses boys' disruptive behavior in the classroom, teachers' resignation to it, and why schools need to work with boys as a matter of importance to enhancing gender work in schools. The limitations of using sex role theory in approaching gender work with boys are highlighted, and teaching methods for harnessing boys' spontaneous interests in…

  15. Modelling Favourability for Invasive Species Encroachment to Identify Areas of Native Species Vulnerability

    OpenAIRE

    Romero, David; Báez, José C.; Ferri-Yáñez, Francisco; Bellido, Jesús J.; Real, Raimundo

    2014-01-01

    We assessed the vulnerability of the native Mediterranean pond turtle to encroachment by the invasive red-eared slider in southern Spain. We first obtained an ecogeographical favourability model for the Mediterranean pond turtle. We then modelled the presence/absence of the red-eared slider in the Mediterranean pond turtle range and obtained an encroachment favourability model. We also obtained a favourability model for the red-eared slider using the ecogeographical favourability for the Medi...

  16. Identifying and Quantifying Emergent Behavior Through System of Systems Modeling and Simulation

    Science.gov (United States)

    2015-09-01

    the similarities and differences between Agent Based Modeling ( ABM ) and Equation Based Modeling (EBM). Both modeling approaches “simulate a system by...entities. For the latter difference, EBM focuses on the system level observables, while ABM defines behaviors at the individual agent level and observes...EMERGENT BEHAVIOR THROUGH SYSTEM OF SYSTEMS MODELING AND SIMULATION by Mary Ann Cummings September 2015 Dissertation Supervisor: Man-Tak Shing

  17. Model trees for identifying exceptional players in the NHL and NBA draft

    OpenAIRE

    Liu, Yejia

    2018-01-01

    Drafting players is crucial for a team’s success. We describe a data-driven interpretable approach for assessing prospects in the National Hockey League and National Basketball Association. Previous approaches have built a predictive model based on player features, or derived performance predictions from comparable players. Our work develops model tree learning, which incorporates strengths of both model-based and cohort-based approaches. A model tree partitions the feature space according to...

  18. Fiction and reality in the modelling world - Balance between simplicity and complexity, calibration and identifiability, verification and falsification

    DEFF Research Database (Denmark)

    Harremoës, P.; Madsen, H.

    1999-01-01

    Where is the balance between simplicity and complexity in model prediction of urban drainage structures? The calibration/verification approach to testing of model performance gives an exaggerated sense of certainty. Frequently, the model structure and the parameters are not identifiable by calibr......Where is the balance between simplicity and complexity in model prediction of urban drainage structures? The calibration/verification approach to testing of model performance gives an exaggerated sense of certainty. Frequently, the model structure and the parameters are not identifiable...... by calibration/verification on the basis of the data series available, which generates elements of sheer guessing - unless the universality of the model is be based on induction, i.e. experience from the sum of all previous investigations. There is a need to deal more explicitly with uncertainty...

  19. Pubertal development timing in urban Chinese boys.

    Science.gov (United States)

    Ma, H-M; Chen, S-K; Chen, R-M; Zhu, C; Xiong, F; Li, T; Wang, W; Liu, G-L; Luo, X-P; Liu, L; Du, M-L

    2011-10-01

    We describe current pubertal development in healthy urban Chinese boys. A cross-sectional study of the pubertal development of 18,807 urban Chinese boys aged from 3.50 to 18.49years was conducted between 2003 and 2005. Testicular volume was evaluated with a Prader orchidometer. Pubic hair development was assessed according to the Tanner method. Data on spermarche were collected using the status quo method. Probit analysis was used to calculate the median age and 95% CI at different stages of testicular development, pubic hair development and spermarche. By age 9, 12.99% of the boys had a testicular volume of 4mL or greater. The median age of onset of puberty defined as the age at attainment of testicular volume of 4mL or greater was 10.55 (95% CI 10.27-10.79) years. The median age for onset of pubic hair development (PH(2) ) and spermarche was 12.78 (95%CI 12.67-12.89) years and 14.05 (95%CI 13.80-14.32) years, respectively. Pubertal onset in urban Chinese boys is earlier than currently used clinical norms but their pubic hair development occurs relatively late in comparison with the reported data from numerous other countries. There is also evidence of a secular trend towards an earlier age of spermarche since 1979 in Chinese urban boys. © 2011 The Authors. International Journal of Andrology © 2011 European Academy of Andrology.

  20. Unsuspected urological anomalies in asymptomatic cryptorchid boys

    International Nuclear Information System (INIS)

    Pappis, C.H.; Argianas, S.A.; Bousgas, D.; Athanasiades, E.; Pendeli Children's Hospital, Athens

    1988-01-01

    In a period of 6 years 144 asymptomatic boys with cryptorchidism, of mean age 7 ± SD 3.5 years, underwent orchiopexy. None of these boys referred to a history of a known urological anomaly, urinary tract infection haematuria, palpable mass in the renal region, bladder extrophy, epispadias, hypospadias or anorectal malformation. On the third day after orchiopexy an intravenous pyelography was done in every boy following testicular protection against irradiation. Ultrasonic investigation was not available at that time. There were minor urological abnormalities in 36 (25%) boys and major ones in 8 (5.5%) boys. A major anomaly is defined as one resulting in significant loss of renal substance (one case of single kidney and three cases of unilateral renal hypoplasia), or requiring surgical correction for conservation of the renal substance (one case of ureterocele, two cases of pelviureteric stenosis and one case of vesicoureteric stenosis with ipsilateral hydronephrosis). The unsuspected major urological abnormalities are usually ipsilateral to the more undescended testis. They may be associated with a hernia and are more frequent in bilateral cryptorchidism. In conclusion we encourage the routine use of IVP, or ultrasonic investigation or dynamic renal scanning (99 mTc -DTPA), if it is possible, in all patients undergoing orchiopexy for the detection of an unsuspected major renal anomaly. (orig.)

  1. Foot Structure in Boys with Down Syndrome

    Directory of Open Access Journals (Sweden)

    Ewa Puszczałowska-Lizis

    2017-01-01

    Full Text Available Introduction and Aim. Down syndrome (DS is associated with numerous developmental abnormalities, some of which cause dysfunctions of the posture and the locomotor system. The analysis of selected features of the foot structure in boys with DS versus their peers without developmental disorders is done. Materials and Methods. The podoscopic examination was performed on 30 boys with DS aged 14-15 years. A control group consisted of 30 age- and gender-matched peers without DS. Results. The feet of boys with DS are flatter compared to their healthy peers. The hallux valgus angle is not the most important feature differentiating the shape of the foot in the boys with DS and their healthy peers. In terms of the V toe setting, healthy boys had poorer results. Conclusions. Specialized therapeutic treatment in individuals with DS should involve exercises to increase the muscle strength around the foot joints, enhancing the stabilization in the joints and proprioception. Introducing orthotics and proper footwear is also important. It is also necessary to monitor the state of the foot in order to modify undertaken therapies.

  2. Academic Competence and Social Adjustment of Boys with Learning Disabilities and Boys with Behavior Disorders.

    Science.gov (United States)

    Margalit, Malka

    1989-01-01

    Comparison of 31 elementary grade boys with learning disabilities and 52 boys with behavior disorders who either did or did not also display hyperactive behavior found significant differences between groups on the Classroom Behavior Inventory in three areas: Hostility versus Consideration, Extroversion versus Introversion, and Independence versus…

  3. Successful Boys and Literacy: Are "Literate Boys" Challenging or Repackaging Hegemonic Masculinity?

    Science.gov (United States)

    Skelton, Christine; Francis, Becky

    2011-01-01

    The National Assessment of Educational Progress statistics show that boys are underachieving in literacy compared to girls. Attempts to redress the problem in various Global North countries and particularly Australia and the United Kingdom have failed to make any impact. However, there are boys who are doing well in literacy. The aim of this…

  4. A comparative study to identify a suitable model of ownership for Iran football pro league clubs

    Directory of Open Access Journals (Sweden)

    Saeed Amirnejad

    2018-01-01

    Full Text Available Today the government ownership of the professional football clubs is absolutely illogical view point. Most of sports clubs are conducted by private sector using different models of ownership all over the world. In Iran, government credits benefit was main reason that the professional sport was firstly developed by government firms and organizations. Therefore, the sports team ownership is without the professionalization standards. The present comparative study was to examine the different football club ownership structures of the top leagues and the current condition of Iran football pro league ownership and then present a suitable ownership structure of Iran football clubs to leave behind the government club ownership. Among the initial 120 scientific texts, the thirty two cases including papers, books and reports were found relevant to this study. We studied the ownership prominence and several football club models of ownership focused on stock listing model of ownership, private investor model of ownership, supporter trust model of ownership and Japan partnership model of ownership; theoretical concepts, empirical studies, main findings, strengths and weaknesses were covered in analysis procedure. According to various models of ownership in leagues and the models’ productivity in football clubs, each model of ownership considering national environmental, economic, social conditions has strengths and weaknesses. So, we cannot present a definite model of ownership for Iran football pro league clubs due to different micro-environments of Iran clubs. We need a big planning to provide a supporter-investor mixed model of ownership to Iranian clubs. Considering strengths and weaknesses in the models of ownership as well as the micro and macro environment of Iran football clubs, German model and Japan partnership model are offered as suitable ones to probable new model of ownership in Iran pro league clubs. Consequently, more studies are required

  5. Identifiability of parameters and behaviour of the MCMC chains: a case study using the reaction norm model

    DEFF Research Database (Denmark)

    Shariati, M M; Korsgaard, I R; Sorensen, D

    2009-01-01

    model with unknown covariates (RNUC) is a model in which unknown environmental effects can be inferred jointly with the remaining parameters. The problem of identifiability of parameters at the level of the likelihood and the associated behaviour of MCMC chains were discussed using the RNUC...... as fixed and there are other fixed factors in the model, the contrasts involving environmental effects, the variance of environmental sensitivities (genetic slopes) and the residual variance are the only identifiable parameters. These different identifiability scenarios were generated by changing...... as an example. It was shown theoretically that when environmental effects (covariates) are considered as random effects, estimable functions of the fixed effects, (co)variance components and genetic effects are identifiable as well as the environmental effects. When the environmental effects are treated...

  6. Heightened emotional sensitivity intensifies associations between relational aggression and victimization among girls but not boys: a longitudinal study.

    Science.gov (United States)

    Zimmer-Gembeck, Melanie J; Duffy, Amanda L

    2014-08-01

    Founded in the social process model, the aim of this study was to identify whether the associations of relational aggression with concurrent and subsequent relational victimization differed depending on early adolescents' personal vulnerabilities and gender. The vulnerabilities of interest were social-information processing variables that convey greater emotional sensitivity, including rejection sensitivity, fear of negative evaluation, and avoidance of intimacy. Participants were 358 early adolescents (176 boys, 178 girls) aged 9 to 13 years. Relational aggression and victimization were assessed via peer nominations, whereas the three indicators of emotional sensitivity were assessed via self-report. Overall, results revealed greater relational aggression at Time 1 to be associated with greater relational victimization at both Time 1 and Time 2. However, this finding was qualified by both emotional sensitivity and gender. When considered separately, girls who were relationally aggressive and emotionally sensitive were at increased risk of victimization at both assessment points. In contrast, no link was found between relational aggression and victimization for boys, although relational vulnerabilities did have unique associations with boys' relational victimization. These findings have implications for our understanding of relational aggression and victimization, as well as for the development of interventions aimed at reducing these problems.

  7. It’s harder for boys?

    DEFF Research Database (Denmark)

    LeRoux-Rutledge, Emily; A. Guerlain, Madeleine; B Andersen, Louise

    2015-01-01

    This study examines whether children in rural Zimbabwe have differing representations of their HIV/AIDS-affected peers based on the gender of those peers. A group of 128 children (58 boys, 70 girls) aged 10–14 participated in a draw-and-write exercise, in which they were asked to tell the story......, or to a culture of gender inequality facing HIV/AIDS affected girls – which pays more attention to male suffering than to female suffering....... of either an HIV/AIDS-affected girl child, or an HIV/AIDS-affected boy child. Stories were inductively thematically coded, and then a post hoc statistical analysis was conducted to see if there were differences in the themes that emerged in stories about girls versus stories about boys. The results showed...

  8. Identifying the optimal supply temperature in district heating networks - A modelling approach

    DEFF Research Database (Denmark)

    Mohammadi, Soma; Bojesen, Carsten

    2014-01-01

    of this study is to develop a model for thermo-hydraulic calculation of low temperature DH system. The modelling is performed with emphasis on transient heat transfer in pipe networks. The pseudo-dynamic approach is adopted to model the District Heating Network [DHN] behaviour which estimates the temperature...... dynamically while the flow and pressure are calculated on the basis of steady state conditions. The implicit finite element method is applied to simulate the transient temperature behaviour in the network. Pipe network heat losses, pressure drop in the network and return temperature to the plant...... are calculated in the developed model. The model will serve eventually as a basis to find out the optimal supply temperature in an existing DHN in later work. The modelling results are used as decision support for existing DHN; proposing possible modifications to operate at optimal supply temperature....

  9. Urinary phthalate excretion in 555 healthy Danish boys with and without pubertal gynaecomastia

    DEFF Research Database (Denmark)

    Mieritz, Mikkel G; Frederiksen, Hanne; Sørensen, Kaspar

    2012-01-01

    Pubertal gynaecomastia is a clinical sign of an oestrogen-androgen imbalance, which occurs in 40-60% of adolescent Caucasian boys. In most cases no underlying endocrinopathy can be identified. A recent study reports higher plasma phthalate levels in Turkish boys with pubertal gynaecomastia....... Therefore, we asked whether there was an association between concurrent measures of urinary phthalate metabolites and pubertal timing as well as the presence of gynaecomastia in otherwise healthy boys. We studied a total of 555 healthy boys (age 6.07-19.83 years) as part of the COPENHAGEN Puberty Study....... Anthropometry and pubertal stages (PH1-6 and G1-5) were evaluated, and the presence of gynaecomastia was assessed. Non-fasting blood samples were analysed for serum testosterone and morning urine samples were analysed for the total content of 12 phthalate metabolites (MEP, MnBP, MiBP, MBzP, MEHP, MEHHP, MEOHP...

  10. Mothers of boys with gender identity disorder: a comparison of matched controls.

    Science.gov (United States)

    Marantz, S; Coates, S

    1991-03-01

    This pilot study compared mothers of boys with gender identity disorder (GID) with mothers of normal boys to determine whether differences in psychopathology and child-rearing attitudes and practices could be identified. Results of the Diagnostic Interview for Borderlines and the Beck Depression Inventory revealed that mothers of boys with GID had more symptoms of depression and more often met the criteria for Borderline Personality Disorder than the controls. Fifty-three percent of the mothers of boys with GID compared with only 6% of controls met the diagnosis for Borderline Personality Disorder on the Diagnostic Interview for Borderlines or had symptoms of depression on the Beck Depression Inventory. Results of the Summers and Walsh Symbiosis Scale suggested that mothers of probands had child-rearing attitudes and practices that encouraged symbiosis and discouraged the development of autonomy.

  11. Nothing Else Matters: Model-Agnostic Explanations By Identifying Prediction Invariance

    OpenAIRE

    Ribeiro, Marco Tulio; Singh, Sameer; Guestrin, Carlos

    2016-01-01

    At the core of interpretable machine learning is the question of whether humans are able to make accurate predictions about a model's behavior. Assumed in this question are three properties of the interpretable output: coverage, precision, and effort. Coverage refers to how often humans think they can predict the model's behavior, precision to how accurate humans are in those predictions, and effort is either the up-front effort required in interpreting the model, or the effort required to ma...

  12. Consistent robustness analysis (CRA) identifies biologically relevant properties of regulatory network models.

    Science.gov (United States)

    Saithong, Treenut; Painter, Kevin J; Millar, Andrew J

    2010-12-16

    A number of studies have previously demonstrated that "goodness of fit" is insufficient in reliably classifying the credibility of a biological model. Robustness and/or sensitivity analysis is commonly employed as a secondary method for evaluating the suitability of a particular model. The results of such analyses invariably depend on the particular parameter set tested, yet many parameter values for biological models are uncertain. Here, we propose a novel robustness analysis that aims to determine the "common robustness" of the model with multiple, biologically plausible parameter sets, rather than the local robustness for a particular parameter set. Our method is applied to two published models of the Arabidopsis circadian clock (the one-loop [1] and two-loop [2] models). The results reinforce current findings suggesting the greater reliability of the two-loop model and pinpoint the crucial role of TOC1 in the circadian network. Consistent Robustness Analysis can indicate both the relative plausibility of different models and also the critical components and processes controlling each model.

  13. Structure modeling of all identified G protein-coupled receptors in the human genome.

    Science.gov (United States)

    Zhang, Yang; Devries, Mark E; Skolnick, Jeffrey

    2006-02-01

    G protein-coupled receptors (GPCRs), encoded by about 5% of human genes, comprise the largest family of integral membrane proteins and act as cell surface receptors responsible for the transduction of endogenous signal into a cellular response. Although tertiary structural information is crucial for function annotation and drug design, there are few experimentally determined GPCR structures. To address this issue, we employ the recently developed threading assembly refinement (TASSER) method to generate structure predictions for all 907 putative GPCRs in the human genome. Unlike traditional homology modeling approaches, TASSER modeling does not require solved homologous template structures; moreover, it often refines the structures closer to native. These features are essential for the comprehensive modeling of all human GPCRs when close homologous templates are absent. Based on a benchmarked confidence score, approximately 820 predicted models should have the correct folds. The majority of GPCR models share the characteristic seven-transmembrane helix topology, but 45 ORFs are predicted to have different structures. This is due to GPCR fragments that are predominantly from extracellular or intracellular domains as well as database annotation errors. Our preliminary validation includes the automated modeling of bovine rhodopsin, the only solved GPCR in the Protein Data Bank. With homologous templates excluded, the final model built by TASSER has a global C(alpha) root-mean-squared deviation from native of 4.6 angstroms, with a root-mean-squared deviation in the transmembrane helix region of 2.1 angstroms. Models of several representative GPCRs are compared with mutagenesis and affinity labeling data, and consistent agreement is demonstrated. Structure clustering of the predicted models shows that GPCRs with similar structures tend to belong to a similar functional class even when their sequences are diverse. These results demonstrate the usefulness and robustness

  14. Structure modeling of all identified G protein-coupled receptors in the human genome.

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2006-02-01

    Full Text Available G protein-coupled receptors (GPCRs, encoded by about 5% of human genes, comprise the largest family of integral membrane proteins and act as cell surface receptors responsible for the transduction of endogenous signal into a cellular response. Although tertiary structural information is crucial for function annotation and drug design, there are few experimentally determined GPCR structures. To address this issue, we employ the recently developed threading assembly refinement (TASSER method to generate structure predictions for all 907 putative GPCRs in the human genome. Unlike traditional homology modeling approaches, TASSER modeling does not require solved homologous template structures; moreover, it often refines the structures closer to native. These features are essential for the comprehensive modeling of all human GPCRs when close homologous templates are absent. Based on a benchmarked confidence score, approximately 820 predicted models should have the correct folds. The majority of GPCR models share the characteristic seven-transmembrane helix topology, but 45 ORFs are predicted to have different structures. This is due to GPCR fragments that are predominantly from extracellular or intracellular domains as well as database annotation errors. Our preliminary validation includes the automated modeling of bovine rhodopsin, the only solved GPCR in the Protein Data Bank. With homologous templates excluded, the final model built by TASSER has a global C(alpha root-mean-squared deviation from native of 4.6 angstroms, with a root-mean-squared deviation in the transmembrane helix region of 2.1 angstroms. Models of several representative GPCRs are compared with mutagenesis and affinity labeling data, and consistent agreement is demonstrated. Structure clustering of the predicted models shows that GPCRs with similar structures tend to belong to a similar functional class even when their sequences are diverse. These results demonstrate the usefulness

  15. Continuous agglomerate model for identifying the solute- indifferent part of colloid nanoparticle's surface charge

    International Nuclear Information System (INIS)

    Alfimov, A V; Aryslanova, E M; Chivilikhin, S A

    2016-01-01

    This work proposes an explicit analytical model for the surface potential of a colloidal nano-agglomerate. The model predicts that when an agglomerate reaches a certain critical size, its surface potential becomes independent of the agglomerate radius. The model also provides a method for identifying and quantifying the solute-indifferent charge in nanocolloids, that allows to assess the stability of toxicologically significant parameters of the system. (paper)

  16. Intervention effects from a social marketing campaign to promote HPV vaccination in preteen boys.

    Science.gov (United States)

    Cates, Joan R; Diehl, Sandra J; Crandell, Jamie L; Coyne-Beasley, Tamera

    2014-07-16

    Adoption of human papillomavirus (HPV) vaccination in the US has been slow. In 2011, HPV vaccination of boys was recommended by CDC for routine use at ages 11-12. We conducted and evaluated a social marketing intervention with parents and providers to stimulate HPV vaccination among preteen boys. We targeted parents and providers of 9-13 year old boys in a 13 county NC region. The 3-month intervention included distribution of HPV vaccination posters and brochures to all county health departments plus 194 enrolled providers; two radio PSAs; and an online CME training. A Cox proportional hazards model was fit using NC immunization registry data to examine whether vaccination rates in 9-13 year old boys increased during the intervention period in targeted counties compared to control counties (n=15) with similar demographics. To compare with other adolescent vaccines, similar models were fit for HPV vaccination in girls and meningococcal and Tdap vaccination of boys in the same age range. Moderating effects of age, race, and Vaccines for Children (VFC) eligibility on the intervention were considered. The Cox model showed an intervention effect (β=0.29, HR=1.34, p=.0024), indicating that during the intervention the probability of vaccination increased by 34% in the intervention counties relative to the control counties. Comparisons with HPV vaccination in girls and Tdap and meningococcal vaccination in boys suggest a unique boost for HPV vaccination in boys during the intervention. Model covariates of age, race and VFC eligibility were all significantly associated with vaccination rates (pmarketing techniques can encourage parents and health care providers to vaccinate preteen boys against HPV. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Cryptorchidism in boys with imperforate anus

    DEFF Research Database (Denmark)

    Cortes, Dina; Thorup, J M; Nielsen, Ole Henrik

    1995-01-01

    In a retrospective study of the case reports of 136 boys who were operated on for an imperforate anus and who survived at least 18 months, cryptorchidism was the most common associated anomaly, involving 26 cases (19%). The higher the level of the anorectal malformations, the higher was the incid......In a retrospective study of the case reports of 136 boys who were operated on for an imperforate anus and who survived at least 18 months, cryptorchidism was the most common associated anomaly, involving 26 cases (19%). The higher the level of the anorectal malformations, the higher...

  18. Identifying parasitic current pathways in CIGS solar cells by modelling dark J-V response

    NARCIS (Netherlands)

    Williams, B.L.; Smit, S.; Kniknie, B.J.; Bakker, K.J.; Keuning, W.; Kessels, W.M.M.; Schropp, R.E.I.; Creatore, M.

    2015-01-01

    An equivalent circuit model, which allows for the presence of three types of shunting pathways, has been developed to describe the dark J-V characteristics in CIGS solar cells. Excellent agreement between the model and experimental data was apparent throughout a temperature range of 183-323K.

  19. Half-trek criterion for generic identifiability of linear structural equation models

    NARCIS (Netherlands)

    Foygel, R.; Draisma, J.; Drton, M.

    2012-01-01

    A linear structural equation model relates random variables of interest and corresponding Gaussian noise terms via a linear equation system. Each such model can be represented by a mixed graph in which directed edges encode the linear equations, and bidirected edges indicate possible correlations

  20. Half-trek criterion for generic identifiability of linear structural equation models

    NARCIS (Netherlands)

    Foygel, R.; Draisma, J.; Drton, M.

    2011-01-01

    A linear structural equation model relates random variables of interest and corresponding Gaussian noise terms via a linear equation system. Each such model can be represented by a mixed graph in which directed edges encode the linear equations, and bidirected edges indicate possible correlations

  1. Soft computing model for optimized siRNA design by identifying off target possibilities using artificial neural network model.

    Science.gov (United States)

    Murali, Reena; John, Philips George; Peter S, David

    2015-05-15

    The ability of small interfering RNA (siRNA) to do posttranscriptional gene regulation by knocking down targeted genes is an important research topic in functional genomics, biomedical research and in cancer therapeutics. Many tools had been developed to design exogenous siRNA with high experimental inhibition. Even though considerable amount of work has been done in designing exogenous siRNA, design of effective siRNA sequences is still a challenging work because the target mRNAs must be selected such that their corresponding siRNAs are likely to be efficient against that target and unlikely to accidentally silence other transcripts due to sequence similarity. In some cases, siRNAs may tolerate mismatches with the target mRNA, but knockdown of genes other than the intended target could make serious consequences. Hence to design siRNAs, two important concepts must be considered: the ability in knocking down target genes and the off target possibility on any nontarget genes. So before doing gene silencing by siRNAs, it is essential to analyze their off target effects in addition to their inhibition efficacy against a particular target. Only a few methods have been developed by considering both efficacy and off target possibility of siRNA against a gene. In this paper we present a new design of neural network model with whole stacking energy (ΔG) that enables to identify the efficacy and off target effect of siRNAs against target genes. The tool lists all siRNAs against a particular target with their inhibition efficacy and number of matches or sequence similarity with other genes in the database. We could achieve an excellent performance of Pearson Correlation Coefficient (R=0. 74) and Area Under Curve (AUC=0.906) when the threshold of whole stacking energy is ≥-34.6 kcal/mol. To the best of the author's knowledge, this is one of the best score while considering the "combined efficacy and off target possibility" of siRNA for silencing a gene. The proposed model

  2. Identifying parasitic current pathways in CIGS solar cells by modelling dark J-V response

    NARCIS (Netherlands)

    Williams, B.L.; Smit, S.; Kniknie, B.J.; Bakker, K.; Keuning, W.; Schropp, R.E.I.; Creatore, M.; Kessels, W.M.M.

    2015-01-01

    The non-uniform presence of shunting defects is a significant cause of poor reproducibility across large-area solar cells, or from batch-to-batch for small area cells, but the most commonly used value for shunt parameterisation (the shunt resistance) fails to identify the cause for shunting. Here,

  3. Identifying Pedophiles "Eligible" for Community Notification under Megan's Law: A Multivariate Model for Actuarially Anchored Decisions.

    Science.gov (United States)

    Pallone, Nathaniel J.; Hennessy, James J.; Voelbel, Gerald T.

    1998-01-01

    A scientifically sound methodology for identifying offenders about whose presence the community should be notified is demonstrated. A stepwise multiple regression was calculated among incarcerated pedophiles (N=52) including both psychological and legal data; a precision-weighted equation produced 90.4% "true positives." This methodology can be…

  4. Identifying Professional Teaching Standards Using Rasch Model Analysis: The Case of Northern Cyprus

    Science.gov (United States)

    Alibaba Erden, Hale; Özer, Bekir

    2013-01-01

    Problem Statement: The Teacher's-Act defined for the state-school teachers of North Cyprus shows that teachers are not selected according to any specific standards. In North Cyprus, apart from the exam topics defined at the teacher's exam regulations, there is not any kind of identified standard for teachers. Training qualified teachers based upon…

  5. Consensus QSAR model for identifying novel H5N1 inhibitors.

    Science.gov (United States)

    Sharma, Nitin; Yap, Chun Wei

    2012-08-01

    Due to the importance of neuraminidase in the pathogenesis of influenza virus infection, it has been regarded as the most important drug target for the treatment of influenza. Resistance to currently available drugs and new findings related to structure of the protein requires novel neuraminidase 1 (N1) inhibitors. In this study, a consensus QSAR model with defined applicability domain (AD) was developed using published N1 inhibitors. The consensus model was validated using an external validation set. The model achieved high sensitivity, specificity, and overall accuracy along with low false positive rate (FPR) and false discovery rate (FDR). The performance of model on the external validation set and training set were comparable, thus it was unlikely to be overfitted. The low FPR and low FDR will increase its accuracy in screening large chemical libraries. Screening of ZINC library resulted in 64,772 compounds as probable N1 inhibitors, while 173,674 compounds were defined to be outside the AD of the consensus model. The advantage of the current model is that it was developed using a large and diverse dataset and has a defined AD which prevents its use on compounds that it is not capable of predicting. The consensus model developed in this study is made available via the free software, PaDEL-DDPredictor.

  6. Identifying abnormal connectivity in patients using Dynamic Causal Modelling of fMRI responses.

    Directory of Open Access Journals (Sweden)

    Mohamed L Seghier

    2010-08-01

    Full Text Available Functional imaging studies of brain damaged patients offer a unique opportunity to understand how sensori-motor and cognitive tasks can be carried out when parts of the neural system that support normal performance are no longer available. In addition to knowing which regions a patient activates, we also need to know how these regions interact with one another, and how these inter-regional interactions deviate from normal. Dynamic Causal Modelling (DCM offers the opportunity to assess task-dependent interactions within a set of regions. Here we review its use in patients when the question of interest concerns the characterisation of abnormal connectivity for a given pathology. We describe the currently available implementations of DCM for fMRI responses, varying from the deterministic bilinear models with one-state equation to the stochastic nonlinear models with two-state equations. We also highlight the importance of the new Bayesian model selection and averaging tools that allow different plausible models to be compared at the single subject and group level. These procedures allow inferences to be made at different levels of model selection, from features (model families to connectivity parameters. Following a critical review of previous DCM studies that investigated abnormal connectivity we propose a systematic procedure that will ensure more flexibility and efficiency when using DCM in patients. Finally, some practical and methodological issues crucial for interpreting or generalising DCM findings in patients are discussed.

  7. Identifying anti-growth factors for human cancer cell lines through genome-scale metabolic modeling

    DEFF Research Database (Denmark)

    Ghaffari, Pouyan; Mardinoglu, Adil; Asplund, Anna

    2015-01-01

    Human cancer cell lines are used as important model systems to study molecular mechanisms associated with tumor growth, hereunder how genomic and biological heterogeneity found in primary tumors affect cellular phenotypes. We reconstructed Genome scale metabolic models (GEMs) for eleven cell lines...... based on RNA-Seq data and validated the functionality of these models with data from metabolite profiling. We used cell line-specific GEMs to analyze the differences in the metabolism of cancer cell lines, and to explore the heterogeneous expression of the metabolic subsystems. Furthermore, we predicted...... for inhibition of cell growth may provide leads for the development of efficient cancer treatment strategies....

  8. Examining the Possibilities of Identifying and Modeling Correlations between Product Families and Business Processes

    DEFF Research Database (Denmark)

    Jepsen, Allan Dam; Hvam, Lars

    2010-01-01

    In order for companies to make well founded decisions on the product family makeup, an understanding of the correlation between the complexity of the product family and business processes is required, though it is often not available. This paper investigates the potential of using the Product...... Variant Master (PVM) modeling technique and Process Flow Charts in combination, to analyze the correlation between complexity in product families and business processes. The approach is based on a visual modeling of the product assortment and the business processes. It is hypothesized that the combined...... use of the modeling techniques can allow for analysis and communication of the product family and business processes; as well as the connections between the two, with the potential of creating a single combined model. A case from a Danish industrial company is used for the purpose of the investigation...

  9. Potential uses of genetic geological modelling to identify new uranium provinces

    International Nuclear Information System (INIS)

    Finch, W.I.

    1982-01-01

    Genetic-geological modelling is the placing of the various processes of the development of a uranium province into distinct stages that are ordered chronologically and made part of a matrix with corresponding geologic evidence. The models can be applied to a given region by using one of several methods to determine a numerical favorability rating. Two of the possible methods, geologic decision analysis and an oil-and-gas type of play analysis, are briefly described. Simplified genetic models are given for environments of the quartz-pebble conglomerate, unconformity-related vein, and sandstone types of deposits. Comparison of the genetic models of these three sedimentary-related environments reveals several common attributes that may define a general uranium province environment

  10. Accuracy of topographic index models at identifying ephemeral gully trajectories on agricultural fields

    Science.gov (United States)

    Sheshukov, Aleksey Y.; Sekaluvu, Lawrence; Hutchinson, Stacy L.

    2018-04-01

    Topographic index (TI) models have been widely used to predict trajectories and initiation points of ephemeral gullies (EGs) in agricultural landscapes. Prediction of EGs strongly relies on the selected value of critical TI threshold, and the accuracy depends on topographic features, agricultural management, and datasets of observed EGs. This study statistically evaluated the predictions by TI models in two paired watersheds in Central Kansas that had different levels of structural disturbances due to implemented conservation practices. Four TI models with sole dependency on topographic factors of slope, contributing area, and planform curvature were used in this study. The observed EGs were obtained by field reconnaissance and through the process of hydrological reconditioning of digital elevation models (DEMs). The Kernel Density Estimation analysis was used to evaluate TI distribution within a 10-m buffer of the observed EG trajectories. The EG occurrence within catchments was analyzed using kappa statistics of the error matrix approach, while the lengths of predicted EGs were compared with the observed dataset using the Nash-Sutcliffe Efficiency (NSE) statistics. The TI frequency analysis produced bi-modal distribution of topographic indexes with the pixels within the EG trajectory having a higher peak. The graphs of kappa and NSE versus critical TI threshold showed similar profile for all four TI models and both watersheds with the maximum value representing the best comparison with the observed data. The Compound Topographic Index (CTI) model presented the overall best accuracy with NSE of 0.55 and kappa of 0.32. The statistics for the disturbed watershed showed higher best critical TI threshold values than for the undisturbed watershed. Structural conservation practices implemented in the disturbed watershed reduced ephemeral channels in headwater catchments, thus producing less variability in catchments with EGs. The variation in critical thresholds for all

  11. Boys Are Victims, Too: The Influence of Perpetrators' Age and Gender in Sexual Coercion Against Boys.

    Science.gov (United States)

    Miller, Jacqueline A; Smith, Edward A; Caldwell, Linda L; Mathews, Catherine; Wegner, Lisa

    2018-06-01

    Sexual coercion among adolescent boys in South Africa is an underresearched topic despite the frequency of such events. Although quantitative research has illuminated the prevalence of sexual coercion toward boys, it has provided little understanding of the context of sexual coercion for adolescent boys. Given the often severe consequences of sexual coercion, it is important to further understand these experiences to inform prevention efforts. The current study aims to provide a more nuanced understanding of the context of sexual coercion. Data come from the baseline assessment for a translational research evaluation of a school-based intervention. The current study focuses on a subset of early and middle adolescent boys who reported experiencing sexual coercion ( n = 223). Analyses examine boys' reports of their perpetrators' characteristics and details about the sexual coercion encounter. Logistic regression is used to examine how coercion tactics used by the perpetrator differs depending on the perpetrator's age and gender. Eighth-grade boys were most likely to report that their perpetrator was a similar-aged female and that perpetrator's age played a particularly important role in what tactics were used. Adult perpetrators were more likely to use physical force, threaten them, harass them electronically, and drink or use drugs at the time. Results provide important insight into boys' experiences of sexual coercion that have implications for both future research and intervention efforts. Although much research is needed on the topic, intervention programs should recognize that both male and female adolescents can be victim and perpetrator.

  12. An Integrated Model for Identifying Linkages Between the Management of Fuel Treatments, Fire and Ecosystem Services

    Science.gov (United States)

    Bart, R. R.; Anderson, S.; Moritz, M.; Plantinga, A.; Tague, C.

    2015-12-01

    Vegetation fuel treatments (e.g. thinning, prescribed burning) are a frequent tool for managing fire-prone landscapes. However, predicting how fuel treatments may affect future wildfire risk and associated ecosystem services, such as forest water availability and streamflow, remains a challenge. This challenge is in part due to the large range of conditions under which fuel treatments may be implemented, as response is likely to vary with species type, rates of vegetation regrowth, meteorological conditions and physiographic properties of the treated site. It is also due to insufficient understanding of how social factors such as political pressure, public demands and economic constraints affect fuel management decisions. To examine the feedbacks between ecological and social dimensions of fuel treatments, we present an integrated model that links a biophysical model that simulates vegetation and hydrology (RHESSys), a fire spread model (WMFire) and an empirical fuel treatment model that accounts for agency decision-making. We use this model to investigate how management decisions affect landscape fuel loads, which in turn affect fire severity and ecosystem services, which feedback to management decisions on fuel treatments. We hypothesize that this latter effect will be driven by salience theory, which predicts that fuel treatments are more likely to occur following major wildfire events. The integrated model provides a flexible framework for answering novel questions about fuel treatments that span social and ecological domains, areas that have previously been treated separately.

  13. Identifying and Evaluating the Relationships that Control a Land Surface Model's Hydrological Behavior

    Science.gov (United States)

    Koster, Randal D.; Mahanama, Sarith P.

    2012-01-01

    The inherent soil moisture-evaporation relationships used in today 's land surface models (LSMs) arguably reflect a lot of guesswork given the lack of contemporaneous evaporation and soil moisture observations at the spatial scales represented by regional and global models. The inherent soil moisture-runoff relationships used in the LSMs are also of uncertain accuracy. Evaluating these relationships is difficult but crucial given that they have a major impact on how the land component contributes to hydrological and meteorological variability within the climate system. The relationships, it turns out, can be examined efficiently and effectively with a simple water balance model framework. The simple water balance model, driven with multi-decadal observations covering the conterminous United States, shows how different prescribed relationships lead to different manifestations of hydrological variability, some of which can be compared directly to observations. Through the testing of a wide suite of relationships, the simple model provides estimates for the underlying relationships that operate in nature and that should be operating in LSMs. We examine the relationships currently used in a number of different LSMs in the context of the simple water balance model results and make recommendations for potential first-order improvements to these LSMs.

  14. A prediction model to identify hospitalised, older adults with reduced physical performance

    DEFF Research Database (Denmark)

    Bruun, Inge H; Maribo, Thomas; Nørgaard, Birgitte

    2017-01-01

    of discharge, health systems could offer these patients additional therapy to maintain or improve health and prevent institutionalisation or readmission. The principle aim of this study was to identify predictors for persisting, reduced physical performance in older adults following acute hospitalisation......BACKGROUND: Identifying older adults with reduced physical performance at the time of hospital admission can significantly affect patient management and trajectory. For example, such patients could receive targeted hospital interventions such as routine mobilisation. Furthermore, at the time...... admission, falls, physical activity level, self-rated health, use of a walking aid before admission, number of prescribed medications, 30s-CST, and the De Morton Mobility Index. RESULTS: A total of 78 (67%) patients improved in physical performance in the interval between admission and follow-up assessment...

  15. Objective Model Selection for Identifying the Human Feedforward Response in Manual Control

    OpenAIRE

    Drop, F.M.; Pool, D.M.; van Paassen, M.M.; Mulder, M.; Bülthoff, Heinrich H.

    2017-01-01

    Realistic manual control tasks typically involve predictable target signals and random disturbances. The human controller (HC) is hypothesized to use a feedforward control strategy for target-following, in addition to feedback control for disturbance-rejection. Little is known about human feedforward control, partly because common system identification methods have difficulty in identifying whether, and (if so) how, the HC applies a feedforward strategy. In this paper, an identification proce...

  16. A Model for Data Citation in Astronomical Research Using Digital Object Identifiers (DOIs)

    Science.gov (United States)

    Novacescu, Jenny; Peek, Joshua E. G.; Weissman, Sarah; Fleming, Scott W.; Levay, Karen; Fraser, Elizabeth

    2018-05-01

    Standardizing and incentivizing the use of digital object identifiers (DOIs) to aggregate and identify both data analyzed and data generated by a research project will advance the field of astronomy to match best practices in other research fields like geoscience and medicine. An increase in the use of DOIs will prepare the discipline for changing expectations among funding agencies and publishers, who increasingly expect accurate and thorough data citation to accompany scientific outputs. The use of DOIs ensures a robust, sustainable, and interoperable approach to data citation in which due credit is given to the researchers and institutions who produce and maintain the primary data. We describe in this work the advantages of DOIs for data citation and best practices for integrating a DOI service in an astronomical archive. We report on a pilot project carried out in collaboration with AAS journals. During the course of the 1.5-year long pilot, over 75% of submitting authors opted to use the integrated DOI service to clearly identify data analyzed during their research project when prompted at the time of paper submission.

  17. Identifying optimal agricultural countermeasure strategies for a hypothetical contamination scenario using the strategy model

    International Nuclear Information System (INIS)

    Cox, G.; Beresford, N.A.; Alvarez-Farizo, B.; Oughton, D.; Kis, Z.; Eged, K.; Thorring, H.; Hunt, J.; Wright, S.; Barnett, C.L.; Gil, J.M.; Howard, B.J.; Crout, N.M.J.

    2005-01-01

    A spatially implemented model designed to assist the identification of optimal countermeasure strategies for radioactively contaminated regions is described. Collective and individual ingestion doses for people within the affected area are estimated together with collective exported ingestion dose. A range of countermeasures are incorporated within the model, and environmental restrictions have been included as appropriate. The model evaluates the effectiveness of a given combination of countermeasures through a cost function which balances the benefit obtained through the reduction in dose with the cost of implementation. The optimal countermeasure strategy is the combination of individual countermeasures (and when and where they are implemented) which gives the lowest value of the cost function. The model outputs should not be considered as definitive solutions, rather as interactive inputs to the decision making process. As a demonstration the model has been applied to a hypothetical scenario in Cumbria (UK). This scenario considered a published nuclear power plant accident scenario with a total deposition of 1.7 x 10 14 , 1.2 x 10 13 , 2.8 x 10 10 and 5.3 x 10 9 Bq for Cs-137, Sr-90, Pu-239/240 and Am-241, respectively. The model predicts that if no remediation measures were implemented the resulting collective dose would be approximately 36 000 person-Sv (predominantly from 137 Cs) over a 10-year period post-deposition. The optimal countermeasure strategy is predicted to avert approximately 33 000 person-Sv at a cost of approximately pound 160 million. The optimal strategy comprises a mixture of ploughing, AFCF (ammonium-ferric hexacyano-ferrate) administration, potassium fertiliser application, clean feeding of livestock and food restrictions. The model recommends specific areas within the contaminated area and time periods where these measures should be implemented

  18. Visual perception of procedural textures: identifying perceptual dimensions and predicting generation models.

    Science.gov (United States)

    Liu, Jun; Dong, Junyu; Cai, Xiaoxu; Qi, Lin; Chantler, Mike

    2015-01-01

    Procedural models are widely used in computer graphics for generating realistic, natural-looking textures. However, these mathematical models are not perceptually meaningful, whereas the users, such as artists and designers, would prefer to make descriptions using intuitive and perceptual characteristics like "repetitive," "directional," "structured," and so on. To make up for this gap, we investigated the perceptual dimensions of textures generated by a collection of procedural models. Two psychophysical experiments were conducted: free-grouping and rating. We applied Hierarchical Cluster Analysis (HCA) and Singular Value Decomposition (SVD) to discover the perceptual features used by the observers in grouping similar textures. The results suggested that existing dimensions in literature cannot accommodate random textures. We therefore utilized isometric feature mapping (Isomap) to establish a three-dimensional perceptual texture space which better explains the features used by humans in texture similarity judgment. Finally, we proposed computational models to map perceptual features to the perceptual texture space, which can suggest a procedural model to produce textures according to user-defined perceptual scales.

  19. Visual perception of procedural textures: identifying perceptual dimensions and predicting generation models.

    Directory of Open Access Journals (Sweden)

    Jun Liu

    Full Text Available Procedural models are widely used in computer graphics for generating realistic, natural-looking textures. However, these mathematical models are not perceptually meaningful, whereas the users, such as artists and designers, would prefer to make descriptions using intuitive and perceptual characteristics like "repetitive," "directional," "structured," and so on. To make up for this gap, we investigated the perceptual dimensions of textures generated by a collection of procedural models. Two psychophysical experiments were conducted: free-grouping and rating. We applied Hierarchical Cluster Analysis (HCA and Singular Value Decomposition (SVD to discover the perceptual features used by the observers in grouping similar textures. The results suggested that existing dimensions in literature cannot accommodate random textures. We therefore utilized isometric feature mapping (Isomap to establish a three-dimensional perceptual texture space which better explains the features used by humans in texture similarity judgment. Finally, we proposed computational models to map perceptual features to the perceptual texture space, which can suggest a procedural model to produce textures according to user-defined perceptual scales.

  20. Boy George Helsingi-Tallinna geikruiisil

    Index Scriptorium Estoniae

    2006-01-01

    Angel Café & Gayclub ja firmade Tallink ja Madrenalin Ltd korraldatavast geikruiisist Lovebot 2006 (30. apr.-1. mai), kus show-programmi peaesinejateks briti laulja Boy Gerry ja ameerika laulja Sherry Vine (Sherry Vine kontsert ka 29. apr. Tallinnas Angeli klubis)

  1. Gender and Boys' Singing in Early Childhood

    Science.gov (United States)

    Hall, Clare

    2005-01-01

    This article derives from a research project investigating the singing behaviour of a group of Australian boys in their first year of school. The project showed that the genesis of the "missing male" trend in singing at school may be occurring in early childhood. The impact of hegemonic masculinity in early childhood is explored here by…

  2. Preadolescent Girls' and Boys' Virtual MUD Play

    Science.gov (United States)

    Calvert, Sandra L.; Strouse, Gabrielle A.; Strong, Bonnie L.; Huffaker, David A.; Lai, Sean

    2009-01-01

    Same and opposite-sex pairs of preadolescents interacted twice in a MUD, a virtual domain where they created characters known as avatars and socially interacted with one another. Boys interacted primarily through rapid scene shifts and playful exchanges; girls interacted with one another through written dialogue. Opposite-sex pairs lagged behind…

  3. Brucellosis: unusual presentations in two adolescent boys

    Energy Technology Data Exchange (ETDEWEB)

    Piampiano, P.; McLeary, M.; Young, L.W. [Dept. of Radiology, Division of Pediatric Radiology, Loma Linda University Children' s Hospital, Loma Linda, CA (United States); Janner, D. [Div. of Pediatric Infectious Disease, Loma Linda University Medical Center and Children' s Hospital, Loma Linda, CA (United States)

    2000-05-01

    Two boys presented with variable signs and symptoms of infectious disease that challenged diagnosis. One of the two patients had aortic valve vegetations and lower extremity aneurysms, and the other had calvarial osteomyelitis, epidural abscess, pleural effusions, and pulmonary nodules. Only after a battery of bacterial and fungal agglutination tests was the unsuspected diagnosis made in each of brucellosis from Brucella canis. (orig.)

  4. Cervical Synovial Sarcoma In a Young Boy

    African Journals Online (AJOL)

    Synovial sarcomas comprise about 8% of all tumours of somatic soft-tissues, and are the most common sar- comas of the 'hands and feet. Occasionally they may occur in the trunk, but they have rarely been reported in the neck. We present a case of cervical soft-tissue mass pro- ducing symptoms in a 12-year-old-boy.

  5. With Boys and Girls in Mind

    Science.gov (United States)

    Gurian, Michael; Stevens, Kathy

    2004-01-01

    New positron emission tomography (PET) and MRI technologies, which allow looking inside the brains, show that the brains of boys and girls differ both structurally and functionally that profoundly affect the human learning. These gender differences in the brain are corroborated in males and females throughout the world and do not differ…

  6. Brucellosis: unusual presentations in two adolescent boys

    International Nuclear Information System (INIS)

    Piampiano, P.; McLeary, M.; Young, L.W.; Janner, D.

    2000-01-01

    Two boys presented with variable signs and symptoms of infectious disease that challenged diagnosis. One of the two patients had aortic valve vegetations and lower extremity aneurysms, and the other had calvarial osteomyelitis, epidural abscess, pleural effusions, and pulmonary nodules. Only after a battery of bacterial and fungal agglutination tests was the unsuspected diagnosis made in each of brucellosis from Brucella canis. (orig.)

  7. Expansion of the Kano model to identify relevant customer segments and functional requirements

    DEFF Research Database (Denmark)

    Atlason, Reynir Smari; Stefansson, Arnaldur Smari; Wietz, Miriam

    2017-01-01

    The Kano model of customer satisfaction has been widely used to analyse perceived needs of customers. The model provides product developers valuable information about if, and then how much a given functional requirement (FR) will impact customer satisfaction if implemented within a product, system...... or a service. A current limitation of the Kano model is that it does not allow developers to visualise which combined sets of FRs would provide the highest satisfaction between different customer segments. In this paper, a stepwise method to address this particular shortcoming is presented. First......, a traditional Kano analysis is conducted for the different segments of interest. Second, for each FR, relationship functions are integrated between x=0 and x=1. Third, integrals are inserted into a combination matrix crossing segments and FRs, where FRs with the highest sum across the chosen segments...

  8. Identifying musical pieces from fMRI data using encoding and decoding models.

    Science.gov (United States)

    Hoefle, Sebastian; Engel, Annerose; Basilio, Rodrigo; Alluri, Vinoo; Toiviainen, Petri; Cagy, Maurício; Moll, Jorge

    2018-02-02

    Encoding models can reveal and decode neural representations in the visual and semantic domains. However, a thorough understanding of how distributed information in auditory cortices and temporal evolution of music contribute to model performance is still lacking in the musical domain. We measured fMRI responses during naturalistic music listening and constructed a two-stage approach that first mapped musical features in auditory cortices and then decoded novel musical pieces. We then probed the influence of stimuli duration (number of time points) and spatial extent (number of voxels) on decoding accuracy. Our approach revealed a linear increase in accuracy with duration and a point of optimal model performance for the spatial extent. We further showed that Shannon entropy is a driving factor, boosting accuracy up to 95% for music with highest information content. These findings provide key insights for future decoding and reconstruction algorithms and open new venues for possible clinical applications.

  9. Very high resolution regional climate model simulations over Greenland: Identifying added value

    DEFF Research Database (Denmark)

    Lucas-Picher, P.; Wulff-Nielsen, M.; Christensen, J.H.

    2012-01-01

    models. However, the bias between the simulations and the few available observations does not reduce with higher resolution. This is partly explained by the lack of observations in regions where the higher resolution is expected to improve the simulated climate. The RCM simulations show......This study presents two simulations of the climate over Greenland with the regional climate model (RCM) HIRHAM5 at 0.05° and 0.25° resolution driven at the lateral boundaries by the ERA-Interim reanalysis for the period 1989–2009. These simulations are validated against observations from...... that the temperature has increased the most in the northern part of Greenland and at lower elevations over the period 1989–2009. Higher resolution increases the relief variability in the model topography and causes the simulated precipitation to be larger on the coast and smaller over the main ice sheet compared...

  10. Identifying Radiology's Place in the Expanding Landscape of Episode Payment Models.

    Science.gov (United States)

    Rosenkrantz, Andrew B; Hirsch, Joshua A; Allen, Bibb; Harvey, H Benjamin; Nicola, Gregory N

    2017-07-01

    The current fee-for-service system for health care reimbursement in the United Stated is argued to encourage fragmented care delivery and a lack of accountability that predisposes to insufficient focus on quality as well as unnecessary or duplicative resource utilization. Episode payment models (EPMs) seek to improve coordination by linking payments for all services related to a patient's condition or procedure, thereby improving quality and efficiency of care. The CMS Innovation Center has implemented a broadening array of EPMs. Early models with relevance to radiologists include Bundled Payment for Care Improvement (involving 48 possible clinical conditions), Comprehensive Care for Joint Replacement (involving knee and hip replacement), and the Oncology Care Model (involving chemotherapy). In July 2016, CMS expanded the range of EPMs through three new models with mandatory hospital participation addressing inpatient and 90-day postdischarge care for acute myocardial infarction, coronary artery bypass graft, and surgical hip and femur fracture treatment. Moreover, some of the EPMs include tracks that allow participating entities to qualify as an Advanced Alternative Payment Model under the Medicare Access and CHIP Reauthorization Act (MACRA), reaping the associated reporting and payment benefits. Even though none of the available EPMs are radiology specific, the models will nevertheless likely influence reimbursements for some radiologists. Thus, radiologists should partner with hospitals and other specialties in care coordination through these episode-based initiatives, thereby having opportunities to apply their imaging expertise to help lower spending while improving quality and overall levels of health. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  11. Heterogeneity among Peer-Rejected Boys across Middle Childhood: Developmental Pathways of Social Behavior.

    Science.gov (United States)

    Haselager, Gerbert J. T.; Cillessen, Antonius H. N.; Van Lieshout, Cornelius F. M.; Riksen-Walraven, J. Marianne A.; Hartup, Willard W.

    2002-01-01

    This longitudinal study identified subgroups of rejected boys with different developmental pathways of aggression and prosocial behavior during middle childhood. Four subgroups were identified associated with different patterns of sociometric acceptance and rejection over time and with social emotional adjustment in the last measurement wave.…

  12. Circular RNA Profiling and Bioinformatic Modeling Identify Its Regulatory Role in Hepatic Steatosis.

    Science.gov (United States)

    Guo, Xing-Ya; He, Chong-Xin; Wang, Yu-Qin; Sun, Chao; Li, Guang-Ming; Su, Qing; Pan, Qin; Fan, Jian-Gao

    2017-01-01

    Circular RNAs (circRNAs) exhibit a wide range of physiological and pathological activities. To uncover their role in hepatic steatosis, we investigated the expression profile of circRNAs in HepG2-based hepatic steatosis induced by high-fat stimulation. Differentially expressed circRNAs were subjected to validation using QPCR and functional analyses using principal component analysis, hierarchical clustering, target prediction, gene ontology (GO), and pathway annotation, respectively. Bioinformatic integration established the circRNA-miRNA-mRNA regulatory network so as to identify the mechanisms underlying circRNAs' metabolic effect. Here we reported that hepatic steatosis was associated with a total of 357 circRNAs. Enrichment of transcription-related GOs, especially GO: 0006355, GO: 004589, GO: 0045944, GO: 0045892, and GO: 0000122, demonstrated their specific actions in transcriptional regulation. Lipin 1 (LPIN1) was recognized to mediate the transcriptional regulatory effect of circRNAs on metabolic pathways. circRNA-miRNA-mRNA network further identified the signaling cascade of circRNA_021412/miR-1972/LPIN1, which was characterized by decreased level of circRNA_021412 and miR-1972-based inhibition of LPIN1. LPIN1-induced downregulation of long chain acyl-CoA synthetases (ACSLs) expression finally resulted in the hepatosteatosis. These findings identify circRNAs to be important regulators of hepatic steatosis. Transcription-dependent modulation of metabolic pathways may underlie their effects, partially by the circRNA_021412/miR-1972/LPIN1 signaling.

  13. Identifying the determinants of South Africa's extensive and intensive trade margins: A gravity model approach

    OpenAIRE

    Matthee, Marianne; Santana-Gallego, Maria

    2017-01-01

    Background: The significance of the paper is twofold. Firstly, it adds to the small but growing body of literature focusing on the decomposition of South Africa’s export growth. Secondly, it identifies the determinants of the intensive and extensive margins of South Africa’s exports – a topic that (as far as the authors are concerned) has not been explored before. Aim: This paper aims to investigate a wide range of market access determinants that affect South Africa’s export growth along ...

  14. On the identifiability of the Hill-1948 model with one uniaxial tensile test

    Science.gov (United States)

    Bertin, Morgan; Hild, François; Roux, Stéphane

    2017-06-01

    A uniaxial experiment is performed on an ultra-thin specimen made of 17-7 precipitation hardened stainless steel. An anti-wrinkling setup allows for the characterization of the mechanical behavior with Integrated Digital Image Correlation (IDIC). The result shows that a single uniaxial experiment investigated via IDIC possesses enough data (and even more) to characterize a complete anisotropic elastoplastic model.

  15. Extrapolation of model tests measurements of whipping to identify the dimensioning sea states for container ships

    DEFF Research Database (Denmark)

    Storhaug, Gaute; Andersen, Ingrid Marie Vincent

    2015-01-01

    to small storms. Model tests of three container ships have been carried out in different sea states under realistic assumptions. Preliminary extrapolation of the measured data suggested that moderate storms are dimensioning when whipping is included due to higher maximum speed in moderate storms...

  16. Identifying at-risk employees: A behavioral model for predicting potential insider threats

    Energy Technology Data Exchange (ETDEWEB)

    Greitzer, Frank L.; Kangas, Lars J.; Noonan, Christine F.; Dalton, Angela C.

    2010-09-01

    A psychosocial model was developed to assess an employee’s behavior associated with an increased risk of insider abuse. The model is based on case studies and research literature on factors/correlates associated with precursor behavioral manifestations of individuals committing insider crimes. In many of these crimes, managers and other coworkers observed that the offenders had exhibited signs of stress, disgruntlement, or other issues, but no alarms were raised. Barriers to using such psychosocial indicators include the inability to recognize the signs and the failure to record the behaviors so that they could be assessed by a person experienced in psychosocial evaluations. We have developed a model using a Bayesian belief network with the help of human resources staff, experienced in evaluating behaviors in staff. We conducted an experiment to assess its agreement with human resources and management professionals, with positive results. If implemented in an operational setting, the model would be part of a set of management tools for employee assessment that can raise an alarm about employees who pose higher insider threat risks. In separate work, we combine this psychosocial model’s assessment with computer workstation behavior to raise the efficacy of recognizing an insider crime in the making.

  17. Identifying and Modeling Dynamic Preference Evolution in Multipurpose Water Resources Systems

    Science.gov (United States)

    Mason, E.; Giuliani, M.; Castelletti, A.; Amigoni, F.

    2018-04-01

    Multipurpose water systems are usually operated on a tradeoff of conflicting operating objectives. Under steady state climatic and socioeconomic conditions, such tradeoff is supposed to represent a fair and/or efficient preference. Extreme variability in external forcing might affect water operators' risk aversion and force a change in her/his preference. Properly accounting for these shifts is key to any rigorous retrospective assessment of the operator's behaviors, and to build descriptive models for projecting the future system evolution. In this study, we explore how the selection of different preferences is linked to variations in the external forcing. We argue that preference selection evolves according to recent, extreme variations in system performance: underperforming in one of the objectives pushes the preference toward the harmed objective. To test this assumption, we developed a rational procedure to simulate the operator's preference selection. We map this selection onto a multilateral negotiation, where multiple virtual agents independently optimize different objectives. The agents periodically negotiate a compromise policy for the operation of the system. Agents' attitudes in each negotiation step are determined by the recent system performance measured by the specific objective they maximize. We then propose a numerical model of preference dynamics that implements a concept from cognitive psychology, the availability bias. We test our modeling framework on a synthetic lake operated for flood control and water supply. Results show that our model successfully captures the operator's preference selection and dynamic evolution driven by extreme wet and dry situations.

  18. Effective Drug Delivery in Diffuse Intrinsic Pontine Glioma : A Theoretical Model to Identify Potential Candidates

    NARCIS (Netherlands)

    El-Khouly, Fatma E; van Vuurden, Dannis G; Stroink, Thom; Hulleman, Esther; Kaspers, Gertjan J L; Hendrikse, N Harry; Veldhuijzen van Zanten, Sophie E M

    2017-01-01

    Despite decades of clinical trials for diffuse intrinsic pontine glioma (DIPG), patient survival does not exceed 10% at two years post-diagnosis. Lack of benefit from systemic chemotherapy may be attributed to an intact bloodbrain barrier (BBB). We aim to develop a theoretical model including

  19. Using the Dynamic Model to Identify Stages of Teacher Skills in Assessment

    Science.gov (United States)

    Christoforidou, Margarita; Xirafidou, Elisavet

    2014-01-01

    The article presents the results of two cross-sectional studies that investigate teachers' skills in using various techniques of assessment in mathematics by taking into account the four phases of assessment. The five dimensions of the dynamic model are also taken into account in proposing a framework for measuring teacher skills in assessment.…

  20. Kronecker-ARX models in identifying (2D) spatial-temporal systems

    NARCIS (Netherlands)

    Sinquin, B.; Verhaegen, M.H.G.; Dochain, Denis; Henrion, Didier; Peaucelle, Dimitri

    2017-01-01

    In this paper we address the identification of (2D) spatial-temporal dynamical systems governed by the Vector Auto-Regressive (VAR) form. The coefficient-matrices of the VAR model are parametrized as sums of Kronecker products. When the number of terms in the sum is small compared to the size of

  1. A Systematic Approach for Identifying Level-1 Error Covariance Structures in Latent Growth Modeling

    Science.gov (United States)

    Ding, Cherng G.; Jane, Ten-Der; Wu, Chiu-Hui; Lin, Hang-Rung; Shen, Chih-Kang

    2017-01-01

    It has been pointed out in the literature that misspecification of the level-1 error covariance structure in latent growth modeling (LGM) has detrimental impacts on the inferences about growth parameters. Since correct covariance structure is difficult to specify by theory, the identification needs to rely on a specification search, which,…

  2. A business planning model to identify new safety net clinic locations.

    Science.gov (United States)

    Langabeer, James; Helton, Jeffrey; DelliFraine, Jami; Dotson, Ebbin; Watts, Carolyn; Love, Karen

    2014-01-01

    Community health clinics serving the poor and underserved are geographically expanding due to changes in U.S. health care policy. This paper describes the experience of a collaborative alliance of health care providers in a large metropolitan area who develop a conceptual and mathematical decision model to guide decisions on expanding its network of community health clinics. Community stakeholders participated in a collaborative process that defined constructs they deemed important in guiding decisions on the location of community health clinics. This collaboration also defined key variables within each construct. Scores for variables within each construct were then totaled and weighted into a community-specific optimal space planning equation. This analysis relied entirely on secondary data available from published sources. The model built from this collaboration revolved around the constructs of demand, sustainability, and competition. It used publicly available data defining variables within each construct to arrive at an optimal location that maximized demand and sustainability and minimized competition. This is a model that safety net clinic planners and community stakeholders can use to analyze demographic and utilization data to optimize capacity expansion to serve uninsured and Medicaid populations. Communities can use this innovative model to develop a locally relevant clinic location-planning framework.

  3. Method for identifying process reuse opportunities to enhance the operating model

    CSIR Research Space (South Africa)

    De Vries, M

    2011-12-01

    Full Text Available the volatility of strategy and suggests the use of an operating model (OM), which is a commitment to a way of doing business. The OM creates a company-wide vision for process standardization and data centralization and guides decisions about how a company...

  4. Early Generalized Overgrowth in Boys With Autism

    Science.gov (United States)

    Chawarska, Katarzyna; Campbell, Daniel; Chen, Lisha; Shic, Frederick; Klin, Ami; Chang, Joseph

    2016-01-01

    Context Multiple studies have reported an overgrowth in head circumference (HC) in the first year of life in autism. However, it is unclear whether this phenomenon is independent of overall body growth and whether it is associated with specific social or cognitive features. Objectives To examine the trajectory of early HC growth in autism compared with control groups; to assess whether HC growth in autism is independent of height and weight growth during infancy; and to examine HC growth from birth to 24 months in relationship to social, verbal, cognitive, and adaptive functioning levels. Design Retrospective study. Setting A specialized university-based clinic. Participants Boys diagnosed as having autistic disorder (n=64), pervasive developmental disorder–not otherwise specified (n=34), global developmental delay (n=13), and other developmental problems (n=18) and typically developing boys (n=55). Main Outcome Measures Age-related changes in HC, height, and weight between birth and age 24 months; measures of social, verbal, and cognitive functioning at age 2 years. Results Compared with typically developing controls, boys with autism were significantly longer by age 4.8 months, had a larger HC by age 9.5 months, and weighed more by age 11.4 months (P=.05 for all). None of the other clinical groups showed a similar overgrowth pattern. Boys with autism who were in the top 10% of overall physical size in infancy exhibited greater severity of social deficits (P=.009) and lower adaptive functioning (P=.03). Conclusions Boys with autism experienced accelerated HC growth in the first year of life. However, this phenomenon reflected a generalized process affecting other morphologic features, including height and weight. The study highlights the importance of studying factors that influence not only neuronal development but also skeletal growth in autism. PMID:21969460

  5. Behavioral aggressiveness in boys with sexual precocity

    Directory of Open Access Journals (Sweden)

    Bindu Kulshreshtha

    2012-01-01

    Full Text Available Background: Some boys with sexual precocity are known to have behavioral problems like increased physical and verbal aggression and school and social maladjustments. It is believed to be due to premature androgen exposure. However, it is not clear why only some develop this problem, difference in etiology could be one explanation. Aim: The aim of the study is to assess behavioral aggression in boys with sexual precocity due to different disorders. Materials and Methods: Seven children, ages three to seven years, were enrolled for this study. Two were diagnosed to have congenital adrenal hyperplasia (CAH, three had testotoxicosis, while two had central precocious puberty. Parents of children with precocious puberty underwent the (CASP questionnaire (children′s aggression scale-parent version. Results: Testosterone levels were high in all patients. Parents denied any history of physical or verbal aggression in the two boys with CAH. Their CASP rating was 0. In contrast, the CASP ratings in the two boys with testotoxicosis and the two with precocious puberty for five domains ranged from 3.1 - 24.2, 2.6 - 8.3,1-5.6,0 - 7.1, and 0 - 1, respectively. In the present study, increased aggression was seen among all the patients with testotoxicosis and both with precocious puberty. In contrast, there were no symptoms of either increased verbal or physical aggression in either of the two patients with CAH. Conclusions: The hormonal milieu in the boys with CAH versus those with sexual precocity due to other causes differed in terms of cortisol and androgen precursors. The androgen excess in CAH children was a consequence of cortisol deficiency. It is possible that cortisol sufficiency is required for androgen-mediated behavioral effects.

  6. Hybrid Cubature Kalman filtering for identifying nonlinear models from sampled recording: Estimation of neuronal dynamics.

    Science.gov (United States)

    Madi, Mahmoud K; Karameh, Fadi N

    2017-01-01

    Kalman filtering methods have long been regarded as efficient adaptive Bayesian techniques for estimating hidden states in models of linear dynamical systems under Gaussian uncertainty. Recent advents of the Cubature Kalman filter (CKF) have extended this efficient estimation property to nonlinear systems, and also to hybrid nonlinear problems where by the processes are continuous and the observations are discrete (continuous-discrete CD-CKF). Employing CKF techniques, therefore, carries high promise for modeling many biological phenomena where the underlying processes exhibit inherently nonlinear, continuous, and noisy dynamics and the associated measurements are uncertain and time-sampled. This paper investigates the performance of cubature filtering (CKF and CD-CKF) in two flagship problems arising in the field of neuroscience upon relating brain functionality to aggregate neurophysiological recordings: (i) estimation of the firing dynamics and the neural circuit model parameters from electric potentials (EP) observations, and (ii) estimation of the hemodynamic model parameters and the underlying neural drive from BOLD (fMRI) signals. First, in simulated neural circuit models, estimation accuracy was investigated under varying levels of observation noise (SNR), process noise structures, and observation sampling intervals (dt). When compared to the CKF, the CD-CKF consistently exhibited better accuracy for a given SNR, sharp accuracy increase with higher SNR, and persistent error reduction with smaller dt. Remarkably, CD-CKF accuracy shows only a mild deterioration for non-Gaussian process noise, specifically with Poisson noise, a commonly assumed form of background fluctuations in neuronal systems. Second, in simulated hemodynamic models, parametric estimates were consistently improved under CD-CKF. Critically, time-localization of the underlying neural drive, a determinant factor in fMRI-based functional connectivity studies, was significantly more accurate

  7. Identifying data gaps and prioritizing restoration strategies for Fremont cottonwood using linked geomorphic and population models

    Science.gov (United States)

    Harper, E. B.; Stella, J. C.; Fremier, A. K.

    2009-12-01

    Fremont cottonwood (Populus fremontii) is an important component of semi-arid riparian ecosystems throughout western North America, but its populations are in decline due to flow regulation. Achieving a balance between human resource needs and riparian ecosystem function requires a mechanistic understanding of the multiple geomorphic and biological factors affecting tree recruitment and survival, including the timing and magnitude of river flows, and the concomitant influence on suitable habitat creation and mortality from scour and sedimentation burial. Despite a great deal of empirical research on some components of the system, such as factors affecting cottonwood recruitment, other key components are less studied. Yet understanding the relative influence of the full suite of physical and life-history drivers is critical to modeling whole-population dynamics under changing environmental conditions. We addressed these issues for the Fremont cottonwood population along the Sacramento River, CA using a sensitivity analysis approach to quantify uncertainty in parameters on the outcomes of a patch-based, dynamic population model. Using a broad range of plausible values for 15 model parameters that represent key physical, biological and climatic components of the ecosystem, we ran 1,000 population simulations that consisted of a subset of 14.3 million possible combinations of parameter estimates to predict the frequency of patch colonization and total forest habitat predicted to occur under current hydrologic conditions after 175 years. Results indicate that Fremont cottonwood populations are highly sensitive to the interactions among flow regime, sedimentation rate and the depth of the capillary fringe (Fig. 1). Estimates of long-term floodplain sedimentation rate would substantially improve model accuracy. Spatial variation in sediment texture was also important to the extent that it determines the depth of the capillary fringe, which regulates the availability of

  8. Hybrid Cubature Kalman filtering for identifying nonlinear models from sampled recording: Estimation of neuronal dynamics

    Science.gov (United States)

    2017-01-01

    Kalman filtering methods have long been regarded as efficient adaptive Bayesian techniques for estimating hidden states in models of linear dynamical systems under Gaussian uncertainty. Recent advents of the Cubature Kalman filter (CKF) have extended this efficient estimation property to nonlinear systems, and also to hybrid nonlinear problems where by the processes are continuous and the observations are discrete (continuous-discrete CD-CKF). Employing CKF techniques, therefore, carries high promise for modeling many biological phenomena where the underlying processes exhibit inherently nonlinear, continuous, and noisy dynamics and the associated measurements are uncertain and time-sampled. This paper investigates the performance of cubature filtering (CKF and CD-CKF) in two flagship problems arising in the field of neuroscience upon relating brain functionality to aggregate neurophysiological recordings: (i) estimation of the firing dynamics and the neural circuit model parameters from electric potentials (EP) observations, and (ii) estimation of the hemodynamic model parameters and the underlying neural drive from BOLD (fMRI) signals. First, in simulated neural circuit models, estimation accuracy was investigated under varying levels of observation noise (SNR), process noise structures, and observation sampling intervals (dt). When compared to the CKF, the CD-CKF consistently exhibited better accuracy for a given SNR, sharp accuracy increase with higher SNR, and persistent error reduction with smaller dt. Remarkably, CD-CKF accuracy shows only a mild deterioration for non-Gaussian process noise, specifically with Poisson noise, a commonly assumed form of background fluctuations in neuronal systems. Second, in simulated hemodynamic models, parametric estimates were consistently improved under CD-CKF. Critically, time-localization of the underlying neural drive, a determinant factor in fMRI-based functional connectivity studies, was significantly more accurate

  9. Trace Metal Bioremediation: Assessment of Model Components from Laboratory and Field Studies to Identify Critical Variables

    International Nuclear Information System (INIS)

    Peter Jaffe; Herschel Rabitz

    2003-01-01

    The objective of this project was to gain an insight into the modeling support needed for the understanding, design, and operation of trace metal/radionuclide bioremediation. To achieve this objective, a workshop was convened to discuss the elements such a model should contain. A ''protomodel'' was developed, based on the recommendations of the workshop, and was used to perform sensitivity analysis as well as some preliminary simulations in support for bioremediation test experiments at UMTRA sites. To simulate the numerous biogeochemical processes that will occur during the bioremediation of uranium contaminated aquifers, a time-dependent one-dimensional reactive transport model has been developed. The model consists of a set of coupled, steady state mass balance equations, accounting for advection, diffusion, dispersion, and a kinetic formulation of the transformations affecting an organic substrate, electron acceptors, corresponding reduced species, and uranium. This set of equations is solved numerically, using a finite element scheme. The redox conditions of the domain are characterized by estimating the pE, based on the concentrations of the dominant terminal electron acceptor and its corresponding reduced specie. This pE and the concentrations of relevant species are passed to a modified version of MINTEQA2, which calculates the speciation and solubilities of the species of interest. Kinetics of abiotic reactions are described as being proportional to the difference between the actual and equilibrium concentration. A global uncertainty assessment, determined by Random Sampling High Dimensional Model Representation (RS-HDMR), was performed to attain a phenomenological understanding of the origins of output variability and to suggest input parameter refinements as well as to provide guidance for field experiments to improve the quality of the model predictions. Results indicated that for the usually high nitrate contents found ate many DOE sites, overall

  10. Optimizing the molecular diagnosis of CDKL5 gene-related epileptic encephalopathy in boys.

    Science.gov (United States)

    Mei, Davide; Darra, Francesca; Barba, Carmen; Marini, Carla; Fontana, Elena; Chiti, Laura; Parrini, Elena; Dalla Bernardina, Bernardo; Guerrini, Renzo

    2014-11-01

    Mutations involving the cyclin-dependent kinase-like 5 (CDKL5) gene cause an early onset epileptic encephalopathy (EE) with severe neurologic impairment and a skewed 12:1 female-to-male ratio. To date, 18 mutations have been described in boys. We analyzed our cohort of boys with early onset EE to assess the diagnostic yield of our molecular approach. We studied 74 boys who presented early onset severe seizures, including infantile spasms and developmental delay, in the setting of EE, using Sanger sequencing, next-generation sequencing (NGS) and multiplex ligation-dependent probe amplification (MLPA). We identified alterations involving CDKL5 in four boys (5.4%) using NGS in one and MLPA in three. Three of four mutations were indicative of somatic mosaicism. CDKL5 gene mutations accounted for 5.4% of boys with early onset EE. Somatic mosaic mutations might be even more represented than germline mutations, probably because their less deleterious effect enhances viability of the male embryo. The molecular approach used for CDKL5 screening remarkably influences the diagnostic yield in boys. Diagnosis is optimized by Sanger sequencing combined with array-based methods or MLPA; alternatively, NGS targeted resequencing designed to also detect copy number alterations, may be performed. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

  11. Combining multivariate analysis and monosaccharide composition modeling to identify plant cell wall variations by Fourier Transform Near Infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Smith-Moritz Andreia M

    2011-08-01

    Full Text Available Abstract We outline a high throughput procedure that improves outlier detection in cell wall screens using FT-NIR spectroscopy of plant leaves. The improvement relies on generating a calibration set from a subset of a mutant population by taking advantage of the Mahalanobis distance outlier scheme to construct a monosaccharide range predictive model using PLS regression. This model was then used to identify specific monosaccharide outliers from the mutant population.

  12. Explaining academic-track boys' underachievement in language grades: Not a lack of aptitude but students' motivational beliefs and parents' perceptions?

    Science.gov (United States)

    Heyder, Anke; Kessels, Ursula; Steinmayr, Ricarda

    2017-06-01

    Boys earn lower grades in languages than girls. The expectancy-value model by Eccles et al. (, A series of books in psychology. Achievement and achievement motives. Psychological and sociological approaches, W.H. Freeman, San Francisco, CA, 76) is a comprehensive theoretical model for explaining gender differences in educational outcomes. In the past, most studies have focused on girls' disadvantage in math and science and on the role of the students' motivational beliefs. We aimed to explain boys' lower language grades by applying the expectancy-value model while taking into account students' motivational beliefs as well as their aptitude, prior achievement, and socializers' beliefs. In addition, we aimed at exploring the incremental contribution of each potential mediator. Five hundred and twenty German students (age M = 17 years; 58% female) and 374 parents (age M = 47 years). Student-reported ability self-concept (ASC) and task values, parents' perceptions of students' ability, students' prior achievement as reported by schools, and students' verbal intelligence test scores were all tested as mediators of the effect of gender on grades in German while controlling for parents' socioeconomic status. Single-mediator models and a multiple-mediator model were estimated using structural equation modelling. All variables proved to be relevant for explaining boys' underachievement in language grades. Whereas students' ASC, task values, prior achievement, and parents' perceptions mediated the gender effect, verbal intelligence was identified as a suppressor variable increasing the gender effect. Our results challenge the stereotypic belief that boys' lower grades are due to lower verbal aptitude. Rather, students' motivational beliefs and parents' perceptions seem critical factors. Implications for both future research and practice are discussed. © 2017 The British Psychological Society.

  13. A New Algorithm for Identifying Cis-Regulatory Modules Based on Hidden Markov Model

    Directory of Open Access Journals (Sweden)

    Haitao Guo

    2017-01-01

    Full Text Available The discovery of cis-regulatory modules (CRMs is the key to understanding mechanisms of transcription regulation. Since CRMs have specific regulatory structures that are the basis for the regulation of gene expression, how to model the regulatory structure of CRMs has a considerable impact on the performance of CRM identification. The paper proposes a CRM discovery algorithm called ComSPS. ComSPS builds a regulatory structure model of CRMs based on HMM by exploring the rules of CRM transcriptional grammar that governs the internal motif site arrangement of CRMs. We test ComSPS on three benchmark datasets and compare it with five existing methods. Experimental results show that ComSPS performs better than them.

  14. A New Algorithm for Identifying Cis-Regulatory Modules Based on Hidden Markov Model

    Science.gov (United States)

    2017-01-01

    The discovery of cis-regulatory modules (CRMs) is the key to understanding mechanisms of transcription regulation. Since CRMs have specific regulatory structures that are the basis for the regulation of gene expression, how to model the regulatory structure of CRMs has a considerable impact on the performance of CRM identification. The paper proposes a CRM discovery algorithm called ComSPS. ComSPS builds a regulatory structure model of CRMs based on HMM by exploring the rules of CRM transcriptional grammar that governs the internal motif site arrangement of CRMs. We test ComSPS on three benchmark datasets and compare it with five existing methods. Experimental results show that ComSPS performs better than them. PMID:28497059

  15. Improving probabilistic prediction of daily streamflow by identifying Pareto optimal approaches for modelling heteroscedastic residual errors

    Science.gov (United States)

    David, McInerney; Mark, Thyer; Dmitri, Kavetski; George, Kuczera

    2017-04-01

    This study provides guidance to hydrological researchers which enables them to provide probabilistic predictions of daily streamflow with the best reliability and precision for different catchment types (e.g. high/low degree of ephemerality). Reliable and precise probabilistic prediction of daily catchment-scale streamflow requires statistical characterization of residual errors of hydrological models. It is commonly known that hydrological model residual errors are heteroscedastic, i.e. there is a pattern of larger errors in higher streamflow predictions. Although multiple approaches exist for representing this heteroscedasticity, few studies have undertaken a comprehensive evaluation and comparison of these approaches. This study fills this research gap by evaluating 8 common residual error schemes, including standard and weighted least squares, the Box-Cox transformation (with fixed and calibrated power parameter, lambda) and the log-sinh transformation. Case studies include 17 perennial and 6 ephemeral catchments in Australia and USA, and two lumped hydrological models. We find the choice of heteroscedastic error modelling approach significantly impacts on predictive performance, though no single scheme simultaneously optimizes all performance metrics. The set of Pareto optimal schemes, reflecting performance trade-offs, comprises Box-Cox schemes with lambda of 0.2 and 0.5, and the log scheme (lambda=0, perennial catchments only). These schemes significantly outperform even the average-performing remaining schemes (e.g., across ephemeral catchments, median precision tightens from 105% to 40% of observed streamflow, and median biases decrease from 25% to 4%). Theoretical interpretations of empirical results highlight the importance of capturing the skew/kurtosis of raw residuals and reproducing zero flows. Recommendations for researchers and practitioners seeking robust residual error schemes for practical work are provided.

  16. Effective Drug Delivery in Diffuse Intrinsic Pontine Glioma: A Theoretical Model to Identify Potential Candidates

    Directory of Open Access Journals (Sweden)

    Fatma E. El-Khouly

    2017-10-01

    Full Text Available Despite decades of clinical trials for diffuse intrinsic pontine glioma (DIPG, patient survival does not exceed 10% at two years post-diagnosis. Lack of benefit from systemic chemotherapy may be attributed to an intact bloodbrain barrier (BBB. We aim to develop a theoretical model including relevant physicochemical properties in order to review whether applied chemotherapeutics are suitable for passive diffusion through an intact BBB or whether local administration via convection-enhanced delivery (CED may increase their therapeutic potential. Physicochemical properties (lipophilicity, molecular weight, and charge in physiological environment of anticancer drugs historically and currently administered to DIPG patients, that affect passive diffusion over the BBB, were included in the model. Subsequently, the likelihood of BBB passage of these drugs was ascertained, as well as their potential for intratumoral administration via CED. As only non-molecularly charged, lipophilic, and relatively small sized drugs are likely to passively diffuse through the BBB, out of 51 drugs modeled, only 8 (15%—carmustine, lomustine, erlotinib, vismodegib, lenalomide, thalidomide, vorinostat, and mebendazole—are theoretically qualified for systemic administration in DIPG. Local administration via CED might create more therapeutic options, excluding only positively charged drugs and drugs that are either prodrugs and/or only available as oral formulation. A wide variety of drugs have been administered systemically to DIPG patients. Our model shows that only few are likely to penetrate the BBB via passive diffusion, which may partly explain the lack of efficacy. Drug distribution via CED is less dependent on physicochemical properties and may increase the therapeutic options for DIPG.

  17. Identifying spikes and seasonal components in electricity spot price data: A guide to robust modeling

    International Nuclear Information System (INIS)

    Janczura, Joanna; Trück, Stefan; Weron, Rafał; Wolff, Rodney C.

    2013-01-01

    An important issue in fitting stochastic models to electricity spot prices is the estimation of a component to deal with trends and seasonality in the data. Unfortunately, estimation routines for the long-term and short-term seasonal pattern are usually quite sensitive to extreme observations, known as electricity price spikes. Improved robustness of the model can be achieved by (a) filtering the data with some reasonable procedure for outlier detection, and then (b) using estimation and testing procedures on the filtered data. In this paper we examine the effects of different treatments of extreme observations on model estimation and on determining the number of spikes (outliers). In particular we compare results for the estimation of the seasonal and stochastic components of electricity spot prices using either the original or filtered data. We find significant evidence for a superior estimation of both the seasonal short-term and long-term components when the data have been treated carefully for outliers. Overall, our findings point out the substantial impact the treatment of extreme observations may have on these issues and, therefore, also on the pricing of electricity derivatives like futures and option contracts. An added value of our study is the ranking of different filtering techniques used in the energy economics literature, suggesting which methods could be and which should not be used for spike identification. - Highlights: • First comprehensive study on the impact of spikes on seasonal pattern estimation • The effects of different treatments of spikes on model estimation are examined. • Cleaning spot prices for outliers yields superior estimates of the seasonal pattern. • Removing outliers provides better parameter estimates for the stochastic process. • Rankings of filtering techniques suggested in the literature are provided

  18. Diagnosing observed characteristics of the wet season across Africa to identify deficiencies in climate model simulations

    Science.gov (United States)

    Dunning, C.; Black, E.; Allan, R. P.

    2017-12-01

    The seasonality of rainfall over Africa plays a key role in determining socio-economic impacts for agricultural stakeholders, influences energy supply from hydropower, affects the length of the malaria transmission season and impacts surface water supplies. Hence, failure or delays of these rains can lead to significant socio-economic impacts. Diagnosing and interpreting interannual variability and long-term trends in seasonality, and analysing the physical driving mechanisms, requires a robust definition of African precipitation seasonality, applicable to both observational datasets and model simulations. Here we present a methodology for objectively determining the onset and cessation of multiple wet seasons across the whole of Africa. Compatibility with known physical drivers of African rainfall, consistency with indigenous methods, and generally strong agreement between satellite-based rainfall data sets confirm that the method is capturing the correct seasonal progression of African rainfall. Application of this method to observational datasets reveals that over East Africa cessation of the short rains is 5 days earlier in La Nina years, and the failure of the rains and subsequent humanitarian disaster is associated with shorter as well as weaker rainy seasons over this region. The method is used to examine the representation of the seasonality of African precipitation in CMIP5 model simulations. Overall, atmosphere-only and fully coupled CMIP5 historical simulations represent essential aspects of the seasonal cycle; patterns of seasonal progression of the rainy season are captured, for the most part mean model onset/ cessation dates agree with mean observational dates to within 18 days. However, unlike the atmosphere-only simulations, the coupled simulations do not capture the biannual regime over the southern West African coastline, linked to errors in Gulf of Guinea Sea Surface Temperature. Application to both observational and climate model datasets, and

  19. Habitat suitability models of mountain ungulates: identifying potential areas for conservation

    Czech Academy of Sciences Publication Activity Database

    Paudel, Prakash K.; Hais, M.; Kindlmann, Pavel

    2015-01-01

    Roč. 54, apr (2015), s. 37 ISSN 1021-5506 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk LC06073; GA ČR GB14-36098G Institutional support: RVO:67179843 Keywords : capricornis thar * habitat model * Midhills * Muntiacus muntjak * Naemorhedus goral * Nepal Subject RIV: EH - Ecology, Behaviour Impact factor: 0.885, year: 2015

  20. Data mining and Pattern Recognizing Models for Identifying Inherited Diseases: Challenges and Implications

    OpenAIRE

    Lahiru Iddamalgoda; Partha Sarathi Das; Partha Sarathi Das; Achala Aponso; Vijayaraghava Seshadri Sundararajan; Prashanth Suravajhala; Prashanth Suravajhala; Prashanth Suravajhala; Jayaraman K Valadi

    2016-01-01

    Data mining and pattern recognition methods reveal interesting findings in genetic studies, especially on how genetic makeup is associated with inherited diseases. Although researchers have proposed various data mining models for biomedical approaches, there remains a challenge in accurately determining the responsible genetic factors for prioritizing the single nucleotide polymorphisms (SNP) associated with the disease. In this commentary, we review the state-of-art data mining and pattern r...

  1. Structural equation modeling identifies markers of damage and function in the aging male Fischer 344 rat.

    Science.gov (United States)

    Grunz-Borgmann, Elizabeth A; Nichols, LaNita A; Wiedmeyer, Charles E; Spagnoli, Sean; Trzeciakowski, Jerome P; Parrish, Alan R

    2016-06-01

    The male Fischer 344 rat is an established model to study progressive renal dysfunction that is similar, but not identical, to chronic kidney disease (CKD) in humans. These studies were designed to assess age-dependent alterations in renal structure and function at late-life timepoints, 16-24 months. Elevations in BUN and plasma creatinine were not significant until 24 months, however, elevations in the more sensitive markers of function, plasma cystatin C and proteinuria, were detectable at 16 and 18 months, respectively. Interestingly, cystatin C levels were not corrected by caloric restriction. Urinary Kim-1, a marker of CKD, was elevated as early as 16 months. Klotho gene expression was significantly decreased at 24 months, but not at earlier timepoints. Alterations in renal structure, glomerulosclerosis and tubulointerstitial fibrosis, were noted at 16 months, with little change from 18 to 24 months. Tubulointerstitial inflammation was increased at 16 months, and remained similar from 18 to 24 months. A SEM (structural equation modeling) model of age-related renal dysfunction suggests that proteinuria is a marker of renal damage, while urinary Kim-1 is a marker of both damage and function. Taken together, these results demonstrate that age-dependent nephropathy begins as early as 16 months and progresses rapidly over the next 8 months. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Implant supported prosthesis in an edentulous boy with Hypohidrotic Ectodermal Dysplasia - "A happy boy"

    DEFF Research Database (Denmark)

    Gjørup, Hans; Nyhuus, Lone; Buhl, Jytte

    2009-01-01

    region. 3. At the age of 10 years a new set of dentures were made. This time the upper denture was made as an overdenture supported and retained by 4 implants and a Dolder bar. The surgical procedure included bone grafting from the anterior ramus mandibulae. The boy's subjective judgement of his oral......Implant supported prosthesis in an edentulous boy with Hypohidrotic Ectodermal Dysplasia - "A happy boy". Authors; Gjoerup,H1; Nyhuus,L2; Buhl,J3. 1) Center for Oral Health in Rare Conditions, Aarhus University Hospital 2) Prosthodontic Department, the Dental School, Aarhus University 3) Department...... by the patient and his family. Case presentation The boy was untreated until the age of 5 years. His oral functions were compromised in relation to speech and psychosocial aspects. In the following 6 years, he underwent prosthodontic treatment in three phases. 1. At the age of 5 years a set of complete dentures...

  3. Boy-lovers and their influence on boys: distorted research and anecdotal observations.

    Science.gov (United States)

    Brongersma, E

    1990-01-01

    A wide experience with boy-lovers has convinced the author that one can often learn more about them from reading some excellent novels than from so-called scientific studies. All too often research is unreliable because (1) it assumes pedosexual activity is a positive indicator of pedophilia; (2) no distinction is drawn between pseudo-pedophiles and real pedophiles; (3) no difference is recognized between boys and girls as partners; and (4) it is highly distorted by bias. Representative samples for research cannot be drawn from members of boy-love organizations. The incidence of violence is very low in pedophile contacts with boys. The influence can be strong in lasting relationships; it can be either wholesome or unwholesome. Within a relationship, sex is usually only a secondary element, although it can be important in sexual instruction and education. The impact of the law, the hostility of parents and the problem of the partners' inequality are discussed.

  4. Identifiability of large-scale non-linear dynamic network models applied to the ADM1-case study.

    Science.gov (United States)

    Nimmegeers, Philippe; Lauwers, Joost; Telen, Dries; Logist, Filip; Impe, Jan Van

    2017-06-01

    In this work, both the structural and practical identifiability of the Anaerobic Digestion Model no. 1 (ADM1) is investigated, which serves as a relevant case study of large non-linear dynamic network models. The structural identifiability is investigated using the probabilistic algorithm, adapted to deal with the specifics of the case study (i.e., a large-scale non-linear dynamic system of differential and algebraic equations). The practical identifiability is analyzed using a Monte Carlo parameter estimation procedure for a 'non-informative' and 'informative' experiment, which are heuristically designed. The model structure of ADM1 has been modified by replacing parameters by parameter combinations, to provide a generally locally structurally identifiable version of ADM1. This means that in an idealized theoretical situation, the parameters can be estimated accurately. Furthermore, the generally positive structural identifiability results can be explained from the large number of interconnections between the states in the network structure. This interconnectivity, however, is also observed in the parameter estimates, making uncorrelated parameter estimations in practice difficult. Copyright © 2017. Published by Elsevier Inc.

  5. Improving probabilistic prediction of daily streamflow by identifying Pareto optimal approaches for modeling heteroscedastic residual errors

    Science.gov (United States)

    McInerney, David; Thyer, Mark; Kavetski, Dmitri; Lerat, Julien; Kuczera, George

    2017-03-01

    Reliable and precise probabilistic prediction of daily catchment-scale streamflow requires statistical characterization of residual errors of hydrological models. This study focuses on approaches for representing error heteroscedasticity with respect to simulated streamflow, i.e., the pattern of larger errors in higher streamflow predictions. We evaluate eight common residual error schemes, including standard and weighted least squares, the Box-Cox transformation (with fixed and calibrated power parameter λ) and the log-sinh transformation. Case studies include 17 perennial and 6 ephemeral catchments in Australia and the United States, and two lumped hydrological models. Performance is quantified using predictive reliability, precision, and volumetric bias metrics. We find the choice of heteroscedastic error modeling approach significantly impacts on predictive performance, though no single scheme simultaneously optimizes all performance metrics. The set of Pareto optimal schemes, reflecting performance trade-offs, comprises Box-Cox schemes with λ of 0.2 and 0.5, and the log scheme (λ = 0, perennial catchments only). These schemes significantly outperform even the average-performing remaining schemes (e.g., across ephemeral catchments, median precision tightens from 105% to 40% of observed streamflow, and median biases decrease from 25% to 4%). Theoretical interpretations of empirical results highlight the importance of capturing the skew/kurtosis of raw residuals and reproducing zero flows. Paradoxically, calibration of λ is often counterproductive: in perennial catchments, it tends to overfit low flows at the expense of abysmal precision in high flows. The log-sinh transformation is dominated by the simpler Pareto optimal schemes listed above. Recommendations for researchers and practitioners seeking robust residual error schemes for practical work are provided.

  6. Identifying perceptions of academic reform in pharmacy using a four-frame organizational change model.

    Science.gov (United States)

    Bajis, Dalia; Chaar, Betty; Basheti, Iman A; Moles, Rebekah

    2017-11-10

    In an ever-changing environment, pharmacy education is in the race to catch up and excel to produce competent pharmacists. Examining academic institutions, including schools of pharmacy, their internal systems and framework, it seems appropriate to view these institutions using multiple lenses. Bolman and Deal conceptualized a method to examine organizations using four constructs (structural, human resource, political, and symbolic). The Eastern Mediterranean Region (EMR), with deep-rooted pharmacy education and practice was the setting for this research. To explore factors affecting academic reform in undergraduate pharmacy education in the EMR from stakeholders' and students' perspectives; and to apply Bolman and Deal's four-frame organizational change model to explore how these issues might be viewed. A multiple-method approach was employed and involved collecting, analyzing and integrating qualitative semi-structured interview data with open-ended questions in a survey. Cross-sector stakeholder sample from various EMR countries was recruited and interviewed. Final year pharmacy students from one school of pharmacy in Jordan were surveyed. Emergent themes were indicative that academic reform was addressed by all frames of the Bolman and Deal model. Structural and political frames received substantial weighing pointing to the importance of curricular reform, collaboration and leadership. A need for skillful and role-model teaching academic staff was highlighted, and in harmony with the human resource frame. Issues within the symbolic frame were readily apparent in the data and spanned the other three frames in relation to heritage, customs and cultural barriers. Issues pertinent to academic reform in pharmacy were presented. Viewing change in pharmacy schools from multiple perspectives highlighted the need for structural changes to pharmacy programs, human resource management, political will, leadership, and collaboration. The importance of understanding cultural

  7. Generalizability of the Disease State Index Prediction Model for Identifying Patients Progressing from Mild Cognitive Impairment to Alzheimer's Disease

    NARCIS (Netherlands)

    Hall, A.; Munoz-Ruiz, M.; Mattila, J.; Koikkalainen, J.; Tsolaki, M.; Mecocci, P.; Kloszewska, I.; Vellas, B.; Lovestone, S.; Visser, P.J.; Lotjonen, J.; Soininen, H.

    2015-01-01

    Background: The Disease State Index (DSI) prediction model measures the similarity of patient data to diagnosed stable and progressive mild cognitive impairment (MCI) cases to identify patients who are progressing to Alzheimer's disease. Objectives: We evaluated how well the DSI generalizes across

  8. Explaining Variance and Identifying Predictors of Children's Communication via a Multilevel Model of Single-Case Design Research: Brief Report

    Science.gov (United States)

    Ottley, Jennifer Riggie; Ferron, John M.; Hanline, Mary Frances

    2016-01-01

    The purpose of this study was to explain the variability in data collected from a single-case design study and to identify predictors of communicative outcomes for children with developmental delays or disabilities (n = 4). Using SAS® University Edition, we fit multilevel models with time nested within children. Children's level of baseline…

  9. Methods and Measures: Growth Mixture Modeling--A Method for Identifying Differences in Longitudinal Change among Unobserved Groups

    Science.gov (United States)

    Ram, Nilam; Grimm, Kevin J.

    2009-01-01

    Growth mixture modeling (GMM) is a method for identifying multiple unobserved sub-populations, describing longitudinal change within each unobserved sub-population, and examining differences in change among unobserved sub-populations. We provide a practical primer that may be useful for researchers beginning to incorporate GMM analysis into their…

  10. Phenotypic Screening Identifies Modulators of Amyloid Precursor Protein Processing in Human Stem Cell Models of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Philip W. Brownjohn

    2017-04-01

    Full Text Available Summary: Human stem cell models have the potential to provide platforms for phenotypic screens to identify candidate treatments and cellular pathways involved in the pathogenesis of neurodegenerative disorders. Amyloid precursor protein (APP processing and the accumulation of APP-derived amyloid β (Aβ peptides are key processes in Alzheimer's disease (AD. We designed a phenotypic small-molecule screen to identify modulators of APP processing in trisomy 21/Down syndrome neurons, a complex genetic model of AD. We identified the avermectins, commonly used as anthelmintics, as compounds that increase the relative production of short Aβ peptides at the expense of longer, potentially more toxic peptides. Further studies demonstrated that this effect is not due to an interaction with the core γ-secretase responsible for Aβ production. This study demonstrates the feasibility of phenotypic drug screening in human stem cell models of Alzheimer-type dementia, and points to possibilities for indirectly modulating APP processing, independently of γ-secretase modulation. : In this article, Livesey and colleagues perform a phenotypic drug screen in a human stem cell model of Alzheimer's disease. The anthelminthic avermectins are identified as a family of compounds that increase the production of short Aβ peptides over longer more toxic Aβ forms. The effect is analogous to existing γ-secretase modulators, but is independent of the core γ-secretase complex. Keywords: neural stem cells, Alzheimer's disease, phenotypic screening, iPSCs, human neurons, dementia, Down syndrome, amyloid beta, ivermectin, selamectin

  11. 3D finite compartment modeling of formation and healing of bruises may identify methods for age determination of bruises

    NARCIS (Netherlands)

    Stam, B.; van Gemert, M.J.C.; van Leeuwen, T.G.; Aalders, M.C.G.

    2010-01-01

    Simulating the spatial and temporal behavior of bruises may identify methods that allow accurate age determination of bruises to assess child abuse. We developed a numerical 3D model to simulate the spatial kinetics of hemoglobin and bilirubin during the formation and healing of bruises. Using this

  12. Utilizing a logic model to identify clinical research problems: a lesson from philosophy of science

    Directory of Open Access Journals (Sweden)

    Collins CR

    2016-10-01

    Full Text Available Cynthia R Collins School of Nursing, College of Social Sciences, Loyola University, New Orleans, LA, USA Abstract: Communication and decision making in the health care workplace often involve finding solutions to ill-structured problems in uncertain, dynamic environments influenced by the competing interests of multiple stakeholders. In this environment, doctoral-prepared nurses who practice as administrators, policy makers, or advanced practice practitioners are often compelled to make important decisions based upon evaluating the merit of colleagues’ proposals against some desired organizational or population outcome. Of equal importance is the nurse leader’s own capacity to construct a compelling argument or proposal that will drive the organization forward to meet the evolving needs for quality health care. Where do we learn the skills necessary to foster this kind of critical thinking in our professional communications? The author suggests that one teaching–learning approach can be found through the thoughtful application of the work of British philosopher Steven Toulmin. Toulmin defined a model for both the analysis and derivation of logical arguments or proposals that can be readily learned and applied for use in health care systems. This model posits that a substantive argument or claim can be evaluated based on the assumptions it presumes (warrants and the strength of the evidence base (backing. Several of the social science professions have adapted Toulmin’s model to generate analysis and creative solutions to complex or emergent problems. The author proposes that an application of this model be included in the pedagogy of doctoral level Philosophy of Science or Nursing Theory courses. The Toulmin process often provides the doctoral student or novice researcher with their first real learning experience in defining the scope and inherent challenges of framing a clinical issue to be the focus of their scholarly translational

  13. Identifiability study of the proteins degradation model, based on ADM1, using simultaneous batch experiments

    DEFF Research Database (Denmark)

    Flotats, X.; Palatsi, J.; Ahring, Birgitte Kiær

    2006-01-01

    are not inhibiting the hydrolysis process. The ADM1 model adequately expressed the consecutive steps of hydrolysis and acidogenesis, with estimated kinetic values corresponding to a fast acidogenesis and slower hydrolysis. The hydrolysis was found to be the rate limiting step of anaerobic degradation. Estimation...... of yield coefficients based on the relative initial slopes of VFA profiles obtained in a simple batch experiment produced satisfactory results. From the identification study, it was concluded that it is possible to determine univocally the related kinetic parameter values for protein degradation...... if the evolution of amino acids is measured in simultaneous batch experiments, with different initial protein and amino acids concentrations....

  14. Investigation of gender role behaviors in boys with hypospadias: comparative study with unaffected boys and girls.

    Science.gov (United States)

    Sung, Ji Yean; Han, Sang Won; Chung, Kyong-Mee; Lee, Hyeyoung; Cho, Sang Hee

    2014-10-01

    The purpose of the study was (1) to investigate gender role behaviors of boys with hypospadias compared with groups of unaffected boys and girls using parental reports and direct observations; and (2) to directly observe effects of socialization (mothers' presence) on children's gender role behaviors. Ages of 19 children with hypospadias ranged from 3 to 7 years, and each of them were matched to controls of unaffected boys and girls by age. All the children participated with their mothers. Children's gender role behaviors and their mothers' behaviors were evaluated using an observation coding system. Mothers also completed questionnaires regarding their children's gender role behaviors. Results indicated no atypical gender role behavior for the boys with hypospadias and no direct effects of socialization on their gender role behaviors. However, differences were found in negative communicative behaviors between boys with hypospadias and unaffected boys, suggesting a possible role of socialization. © The Author 2014. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Prevalence of consistent condom use with various types of sex partners and associated factors among money boys in Changsha, China.

    Science.gov (United States)

    Wang, Lian-Hong; Yan, Jin; Yang, Guo-Li; Long, Shuo; Yu, Yong; Wu, Xi-Lin

    2015-04-01

    Money boys with inconsistent condom use (less than 100% of the time) are at high risk of infection by human immunodeficiency virus (HIV) or sexually transmitted infection (STI), but relatively little research has examined their risk behaviors. We investigated the prevalence of consistent condom use (100% of the time) and associated factors among money boys. A cross-sectional study using a structured questionnaire was conducted among money boys in Changsha, China, between July 2012 and January 2013. Independent variables included socio-demographic data, substance abuse history, work characteristics, and self-reported HIV and STI history. Dependent variables included the consistent condom use with different types of sex partners. Among the participants, 82.4% used condoms consistently with male clients, 80.2% with male sex partners, and 77.1% with female sex partners in the past 3 months. A multiple stepwise logistic regression model identified four statistically significant factors associated with lower likelihoods of consistent condom use with male clients: age group, substance abuse, lack of an "employment" arrangement, and having no HIV test within the prior 6 months. In a similar model, only one factor associated significantly with lower likelihoods of consistent condom use with male sex partners was identified in multiple stepwise logistic regression analyses: having no HIV test within the prior six months. As for female sex partners, two significant variables were statistically significant in the multiple stepwise logistic regression analysis: having no HIV test within the prior 6 months and having STI history. Interventions which are linked with more realistic and acceptable HIV prevention methods are greatly warranted and should increase risk awareness and the behavior of consistent condom use in both commercial and personal relationship. © 2015 International Society for Sexual Medicine.

  16. Identifying a predictive model for response to atypical antipsychotic monotherapy treatment in south Indian schizophrenia patients.

    Science.gov (United States)

    Gupta, Meenal; Moily, Nagaraj S; Kaur, Harpreet; Jajodia, Ajay; Jain, Sanjeev; Kukreti, Ritushree

    2013-08-01

    Atypical antipsychotic (AAP) drugs are the preferred choice of treatment for schizophrenia patients. Patients who do not show favorable response to AAP monotherapy are subjected to random prolonged therapeutic treatment with AAP multitherapy, typical antipsychotics or a combination of both. Therefore, prior identification of patients' response to drugs can be an important step in providing efficacious and safe therapeutic treatment. We thus attempted to elucidate a genetic signature which could predict patients' response to AAP monotherapy. Our logistic regression analyses indicated the probability that 76% patients carrying combination of four SNPs will not show favorable response to AAP therapy. The robustness of this prediction model was assessed using repeated 10-fold cross validation method, and the results across n-fold cross-validations (mean accuracy=71.91%; 95%CI=71.47-72.35) suggest high accuracy and reliability of the prediction model. Further validations of these results in large sample sets are likely to establish their clinical applicability. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Identifying the characteristic of SundaParahiyangan landscape for a model of sustainable agricultural landscape

    Science.gov (United States)

    Dahlan, M. Z.; Nurhayati, H. S. A.; Mugnisjah, W. Q.

    2017-10-01

    This study was an explorative study of the various forms of traditional ecological knowledge (TEK) of Sundanese people in the context of sustainable agriculture. The qualitative method was used to identify SundaParahiyangan landscape by using Rapid Participatory Rural Appraisal throughsemi-structured interviews, focus group discussions, and field survey. The Landscape Characteristic Assessment and Community Sustainability Assessment were used to analyze the characteristic of landscape to achieve the sustainable agricultural landscape criteria proposed by US Department of Agriculture. The results revealed that the SundaParahiyangan agricultural landscape has a unique characteristic as a result of the long-term adaptation of agricultural society to theirlandscape through a learning process for generations. In general, this character was reflected in the typical of Sundanese’s agroecosystems such as forest garden, mixed garden, paddy field, and home garden. In addition, concept of kabuyutan is one of the TEKs related to understanding and utilization of landscape has been adapted on revitalizing the role of landscape surrounding the agroecosystem as the buffer zone by calculating and designating protected areas. To support the sustainability of production area, integrated practices of agroforestry with low-external-input and sustainable agriculture (LEISA) system can be applied in utilizing and managing agricultural resources.

  18. Pluripotent cell models of fanconi anemia identify the early pathological defect in human hemoangiogenic progenitors.

    Science.gov (United States)

    Suzuki, Naoya M; Niwa, Akira; Yabe, Miharu; Hira, Asuka; Okada, Chihiro; Amano, Naoki; Watanabe, Akira; Watanabe, Ken-Ichiro; Heike, Toshio; Takata, Minoru; Nakahata, Tatsutoshi; Saito, Megumu K

    2015-04-01

    Fanconi anemia (FA) is a disorder of genomic instability characterized by progressive bone marrow failure (BMF), developmental abnormalities, and an increased susceptibility to cancer. Although various consequences in hematopoietic stem/progenitor cells have been attributed to FA-BMF, the quest to identify the initial pathological event is still ongoing. To address this issue, we established induced pluripotent stem cells (iPSCs) from fibroblasts of six patients with FA and FANCA mutations. An improved reprogramming method yielded iPSC-like colonies from all patients, and iPSC clones were propagated from two patients. Quantitative evaluation of the differentiation ability demonstrated that the differentiation propensity toward the hematopoietic and endothelial lineages is already defective in early hemoangiogenic progenitors. The expression levels of critical transcription factors were significantly downregulated in these progenitors. These data indicate that the hematopoietic consequences in FA patients originate from the early hematopoietic stage and highlight the potential usefulness of iPSC technology for elucidating the pathogenesis of FA-BMF. ©AlphaMed Press.

  19. Efficient genome-wide association in biobanks using topic modeling identifies multiple novel disease loci.

    Science.gov (United States)

    McCoy, Thomas H; Castro, Victor M; Snapper, Leslie A; Hart, Kamber L; Perlis, Roy H

    2017-08-31

    Biobanks and national registries represent a powerful tool for genomic discovery, but rely on diagnostic codes that may be unreliable and fail to capture the relationship between related diagnoses. We developed an efficient means of conducting genome-wide association studies using combinations of diagnostic codes from electronic health records (EHR) for 10845 participants in a biobanking program at two large academic medical centers. Specifically, we applied latent Dirichilet allocation to fit 50 disease topics based on diagnostic codes, then conducted genome-wide common-variant association for each topic. In sensitivity analysis, these results were contrasted with those obtained from traditional single-diagnosis phenome-wide association analysis, as well as those in which only a subset of diagnostic codes are included per topic. In meta-analysis across three biobank cohorts, we identified 23 disease-associated loci with p<1e-15, including previously associated autoimmune disease loci. In all cases, observed significant associations were of greater magnitude than for single phenome-wide diagnostic codes, and incorporation of less strongly-loading diagnostic codes enhanced association. This strategy provides a more efficient means of phenome-wide association in biobanks with coded clinical data.

  20. Using ensemble models to identify and apportion heavy metal pollution sources in agricultural soils on a local scale

    International Nuclear Information System (INIS)

    Wang, Qi; Xie, Zhiyi; Li, Fangbai

    2015-01-01

    This study aims to identify and apportion multi-source and multi-phase heavy metal pollution from natural and anthropogenic inputs using ensemble models that include stochastic gradient boosting (SGB) and random forest (RF) in agricultural soils on the local scale. The heavy metal pollution sources were quantitatively assessed, and the results illustrated the suitability of the ensemble models for the assessment of multi-source and multi-phase heavy metal pollution in agricultural soils on the local scale. The results of SGB and RF consistently demonstrated that anthropogenic sources contributed the most to the concentrations of Pb and Cd in agricultural soils in the study region and that SGB performed better than RF. - Highlights: • Ensemble models including stochastic gradient boosting and random forest are used. • The models were verified by cross-validation and SGB performed better than RF. • Heavy metal pollution sources on a local scale are identified and apportioned. • Models illustrate good suitability in assessing sources in local-scale agricultural soils. • Anthropogenic sources contributed most to soil Pb and Cd pollution in our case. - Multi-source and multi-phase pollution by heavy metals in agricultural soils on a local scale were identified and apportioned.

  1. A method to identify energy efficiency measures for factory systems based on qualitative modeling

    CERN Document Server

    Krones, Manuela

    2017-01-01

    Manuela Krones develops a method that supports factory planners in generating energy-efficient planning solutions. The method provides qualitative description concepts for factory planning tasks and energy efficiency knowledge as well as an algorithm-based linkage between these measures and the respective planning tasks. Its application is guided by a procedure model which allows a general applicability in the manufacturing sector. The results contain energy efficiency measures that are suitable for a specific planning task and reveal the roles of various actors for the measures’ implementation. Contents Driving Concerns for and Barriers against Energy Efficiency Approaches to Increase Energy Efficiency in Factories Socio-Technical Description of Factory Planning Tasks Description of Energy Efficiency Measures Case Studies on Welding Processes and Logistics Systems Target Groups Lecturers and Students of Industrial Engineering, Production Engineering, Environmental Engineering, Mechanical Engineering Practi...

  2. Bayesian distributed lag interaction models to identify perinatal windows of vulnerability in children's health.

    Science.gov (United States)

    Wilson, Ander; Chiu, Yueh-Hsiu Mathilda; Hsu, Hsiao-Hsien Leon; Wright, Robert O; Wright, Rosalind J; Coull, Brent A

    2017-07-01

    Epidemiological research supports an association between maternal exposure to air pollution during pregnancy and adverse children's health outcomes. Advances in exposure assessment and statistics allow for estimation of both critical windows of vulnerability and exposure effect heterogeneity. Simultaneous estimation of windows of vulnerability and effect heterogeneity can be accomplished by fitting a distributed lag model (DLM) stratified by subgroup. However, this can provide an incomplete picture of how effects vary across subgroups because it does not allow for subgroups to have the same window but different within-window effects or to have different windows but the same within-window effect. Because the timing of some developmental processes are common across subpopulations of infants while for others the timing differs across subgroups, both scenarios are important to consider when evaluating health risks of prenatal exposures. We propose a new approach that partitions the DLM into a constrained functional predictor that estimates windows of vulnerability and a scalar effect representing the within-window effect directly. The proposed method allows for heterogeneity in only the window, only the within-window effect, or both. In a simulation study we show that a model assuming a shared component across groups results in lower bias and mean squared error for the estimated windows and effects when that component is in fact constant across groups. We apply the proposed method to estimate windows of vulnerability in the association between prenatal exposures to fine particulate matter and each of birth weight and asthma incidence, and estimate how these associations vary by sex and maternal obesity status in a Boston-area prospective pre-birth cohort study. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Atmospheric reaction systems as null-models to identify structural traces of evolution in metabolism.

    Directory of Open Access Journals (Sweden)

    Petter Holme

    Full Text Available The metabolism is the motor behind the biological complexity of an organism. One problem of characterizing its large-scale structure is that it is hard to know what to compare it to. All chemical reaction systems are shaped by the same physics that gives molecules their stability and affinity to react. These fundamental factors cannot be captured by standard null-models based on randomization. The unique property of organismal metabolism is that it is controlled, to some extent, by an enzymatic machinery that is subject to evolution. In this paper, we explore the possibility that reaction systems of planetary atmospheres can serve as a null-model against which we can define metabolic structure and trace the influence of evolution. We find that the two types of data can be distinguished by their respective degree distributions. This is especially clear when looking at the degree distribution of the reaction network (of reaction connected to each other if they involve the same molecular species. For the Earth's atmospheric network and the human metabolic network, we look into more detail for an underlying explanation of this deviation. However, we cannot pinpoint a single cause of the difference, rather there are several concurrent factors. By examining quantities relating to the modular-functional organization of the metabolism, we confirm that metabolic networks have a more complex modular organization than the atmospheric networks, but not much more. We interpret the more variegated modular arrangement of metabolism as a trace of evolved functionality. On the other hand, it is quite remarkable how similar the structures of these two types of networks are, which emphasizes that the constraints from the chemical properties of the molecules has a larger influence in shaping the reaction system than does natural selection.

  4. 3D geostatistical modelling for identifying sinkhole disaster potential zones around the Verkhnekamskoye potash deposit (Russia)

    Science.gov (United States)

    Royer, J. J.; Litaudon, J.; Filippov, L. O.; Lyubimova, T.; Maximovich, N.

    2017-07-01

    This work results from a cooperative scientific program between the Perm State University (Russia) and the University of Lorraine (France). Its objectives are to integrate modern 3D geomodeling in order to improve sustainable mining extraction, especially for predicting and avoiding the formation of sinkholes disaster potential zones. Systematic exploration drill holes performed in the Verkhnekamskoye potash deposit (Perm region, Russia) have been used to build a comprehensive 3D model for better understanding the spatial repartition of the ore quality (geometallurgy). A precise modelling of the mineralized layers allows an estimation of the in-situ ore reserves after interpolating by kriging the potassium (K) and magnesium (Mg) contents at the node of a regular centred grid (over a million cells). Total resources in potassium vary according to the cut-off between 4.7Gt @ 16.1 % K2O; 0.32 % MgCl2 for a cut-off grade at 13.1% K2O and 2.06 Gt @ 18.2 % K2O; 0.32 % MgCl2 at a cut-off of 16.5% K2O. Most of reserves are located in the KPI, KPII and KPIII layers, the KPI being the richest, and KPIII the largest in terms of tonnage. A systematic study of the curvature calculated along the roof of the mineralized layers points out the location of potential main faults which play a major role in the formation of sinkhole during exploitation. A risk map is then derived from this attribute.

  5. Identifying HIV most-at-risk groups in Malawi for targeted interventions. A classification tree model.

    Science.gov (United States)

    Emina, Jacques B O; Madise, Nyovani; Kuepie, Mathias; Zulu, Eliya M; Ye, Yazoume

    2013-05-28

    To identify HIV-socioeconomic predictors as well as the most-at-risk groups of women in Malawi. A cross-sectional survey. Malawi The study used a sample of 6395 women aged 15-49 years from the 2010 Malawi Health and Demographic Surveys. Individual HIV status: positive or not. Findings from the Pearson χ(2) and χ(2) Automatic Interaction Detector analyses revealed that marital status is the most significant predictor of HIV. Women who are no longer in union and living in the highest wealth quintiles households constitute the most-at-risk group, whereas the less-at-risk group includes young women (15-24) never married or in union and living in rural areas. In the light of these findings, this study recommends: (1) that the design and implementation of targeted interventions should consider the magnitude of HIV prevalence and demographic size of most-at-risk groups. Preventive interventions should prioritise couples and never married people aged 25-49 years and living in rural areas because this group accounts for 49% of the study population and 40% of women living with HIV in Malawi; (2) with reference to treatment and care, higher priority must be given to promoting HIV test, monitoring and evaluation of equity in access to treatment among women in union disruption and never married or women in union aged 30-49 years and living in urban areas; (3) community health workers, households-based campaign, reproductive-health services and reproductive-health courses at school could be used as canons to achieve universal prevention strategy, testing, counselling and treatment.

  6. Identifying models of HIV care and treatment service delivery in Tanzania, Uganda, and Zambia using cluster analysis and Delphi survey.

    Science.gov (United States)

    Tsui, Sharon; Denison, Julie A; Kennedy, Caitlin E; Chang, Larry W; Koole, Olivier; Torpey, Kwasi; Van Praag, Eric; Farley, Jason; Ford, Nathan; Stuart, Leine; Wabwire-Mangen, Fred

    2017-12-06

    Organization of HIV care and treatment services, including clinic staffing and services, may shape clinical and financial outcomes, yet there has been little attempt to describe different models of HIV care in sub-Saharan Africa (SSA). Information about the relative benefits and drawbacks of different models could inform the scale-up of antiretroviral therapy (ART) and associated services in resource-limited settings (RLS), especially in light of expanded client populations with country adoption of WHO's test and treat recommendation. We characterized task-shifting/task-sharing practices in 19 diverse ART clinics in Tanzania, Uganda, and Zambia and used cluster analysis to identify unique models of service provision. We ran descriptive statistics to explore how the clusters varied by environmental factors and programmatic characteristics. Finally, we employed the Delphi Method to make systematic use of expert opinions to ensure that the cluster variables were meaningful in the context of actual task-shifting of ART services in SSA. The cluster analysis identified three task-shifting/task-sharing models. The main differences across models were the availability of medical doctors, the scope of clinical responsibility assigned to nurses, and the use of lay health care workers. Patterns of healthcare staffing in HIV service delivery were associated with different environmental factors (e.g., health facility levels, urban vs. rural settings) and programme characteristics (e.g., community ART distribution or integrated tuberculosis treatment on-site). Understanding the relative advantages and disadvantages of different models of care can help national programmes adapt to increased client load, select optimal adherence strategies within decentralized models of care, and identify differentiated models of care for clients to meet the growing needs of long-term ART patients who require more complicated treatment management.

  7. Predictive risk modelling under different data access scenarios: who is identified as high risk and for how long?

    Science.gov (United States)

    Johnson, Tracy L; Kaldor, Jill; Sutherland, Kim; Humphries, Jacob; Jorm, Louisa R; Levesque, Jean-Frederic

    2018-01-01

    Objective This observational study critically explored the performance of different predictive risk models simulating three data access scenarios, comparing: (1) sociodemographic and clinical profiles; (2) consistency in high-risk designation across models; and (3) persistence of high-risk status over time. Methods Cross-sectional health survey data (2006–2009) for more than 260 000 Australian adults 45+ years were linked to longitudinal individual hospital, primary care, pharmacy and mortality data. Three risk models predicting acute emergency hospitalisations were explored, simulating conditions where data are accessed through primary care practice management systems, or through hospital-based electronic records, or through a hypothetical ‘full’ model using a wider array of linked data. High-risk patients were identified using different risk score thresholds. Models were reapplied monthly for 24 months to assess persistence in high-risk categorisation. Results The three models displayed similar statistical performance. Three-quarters of patients in the high-risk quintile from the ‘full’ model were also identified using the primary care or hospital-based models, with the remaining patients differing according to age, frailty, multimorbidity, self-rated health, polypharmacy, prior hospitalisations and imminent mortality. The use of higher risk prediction thresholds resulted in lower levels of agreement in high-risk designation across models and greater morbidity and mortality in identified patient populations. Persistence of high-risk status varied across approaches according to updated information on utilisation history, with up to 25% of patients reassessed as lower risk within 1 year. Conclusion/implications Small differences in risk predictors or risk thresholds resulted in comparatively large differences in who was classified as high risk and for how long. Pragmatic predictive risk modelling design decisions based on data availability or projected

  8. Video game use in boys with autism spectrum disorder, ADHD, or typical development.

    Science.gov (United States)

    Mazurek, Micah O; Engelhardt, Christopher R

    2013-08-01

    The study objectives were to examine video game use in boys with autism spectrum disorder (ASD) compared with those with ADHD or typical development (TD) and to examine how specific symptoms and game features relate to problematic video game use across groups. Participants included parents of boys (aged 8-18) with ASD (n = 56), ADHD (n = 44), or TD (n = 41). Questionnaires assessed daily hours of video game use, in-room video game access, video game genres, problematic video game use, ASD symptoms, and ADHD symptoms. Boys with ASD spent more time than did boys with TD playing video games (2.1 vs 1.2 h/d). Both the ASD and ADHD groups had greater in-room video game access and greater problematic video game use than the TD group. Multivariate models showed that inattentive symptoms predicted problematic game use for both the ASD and ADHD groups; and preferences for role-playing games predicted problematic game use in the ASD group only. Boys with ASD spend much more time playing video games than do boys with TD, and boys with ASD and ADHD are at greater risk for problematic video game use than are boys with TD. Inattentive symptoms, in particular, were strongly associated with problematic video game use for both groups, and role-playing game preferences may be an additional risk factor for problematic video game use among children with ASD. These findings suggest a need for longitudinal research to better understand predictors and outcomes of video game use in children with ASD and ADHD.

  9. Who is most affected by prenatal alcohol exposure: Boys or girls?

    Science.gov (United States)

    May, Philip A; Tabachnick, Barbara; Hasken, Julie M; Marais, Anna-Susan; de Vries, Marlene M; Barnard, Ronel; Joubert, Belinda; Cloete, Marise; Botha, Isobel; Kalberg, Wendy O; Buckley, David; Burroughs, Zachary R; Bezuidenhout, Heidre; Robinson, Luther K; Manning, Melanie A; Adnams, Colleen M; Seedat, Soraya; Parry, Charles D H; Hoyme, H Eugene

    2017-08-01

    To examine outcomes among boys and girls that are associated with prenatal alcohol exposure. Boys and girls with fetal alcohol spectrum disorders (FASD) and randomly-selected controls were compared on a variety of physical and neurobehavioral traits. Sex ratios indicated that heavy maternal binge drinking may have significantly diminished viability to birth and survival of boys postpartum more than girls by age seven. Case control comparisons of a variety of physical and neurobehavioral traits at age seven indicate that both sexes were affected similarly for a majority of variables. However, alcohol-exposed girls had significantly more dysmorphology overall than boys and performed significantly worse on non-verbal IQ tests than males. A three-step sequential regression analysis, controlling for multiple covariates, further indicated that dysmorphology among girls was significantly more associated with five maternal drinking variables and three distal maternal risk factors. However, the overall model, which included five associated neurobehavioral measures at step three, was not significant (p=0.09, two-tailed test). A separate sequential logistic regression analysis of predictors of a FASD diagnosis, however, indicated significantly more negative outcomes overall for girls than boys (Nagelkerke R 2 =0.42 for boys and 0.54 for girls, z=-2.9, p=0.004). Boys and girls had mostly similar outcomes when prenatal alcohol exposure was linked to poor physical and neurocognitive development. Nevertheless, sex ratios implicate lower viability and survival of males by first grade, and girls have more dysmorphology and neurocognitive impairment than boys resulting in a higher probability of a FASD diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Why Are Girls Less Physically Active than Boys? Findings from the LOOK Longitudinal Study.

    Science.gov (United States)

    Telford, Rohan M; Telford, Richard D; Olive, Lisa S; Cochrane, Thomas; Davey, Rachel

    2016-01-01

    A gender-based disparity in physical activity (PA) among youth, whereby girls are less active than boys is a persistent finding in the literature. A greater understanding of the mechanisms underlying this difference has potential to guide PA intervention strategies. Data were collected at age 8 and 12 years (276 boys, 279 girls) from 29 schools as part of the LOOK study. Multilevel linear models were fitted separately for boys and girls to examine effects of individual, family and environmental level correlates on pedometer measured PA. Cardio-respiratory fitness (multi-stage run), percent fat (DEXA), eye-hand coordination (throw and catch test) and perceived competence in physical education (questionnaire) were used as individual level correlates. At the family level, parent's support and education (questionnaire) were used. School attended and extracurricular sport participation were included as environmental level correlates. Girls were 19% less active than boys (9420 vs 11360 steps/day, pgirls was associated with weaker influences at the school and family levels and through lower participation in extracurricular sport. School attended explained some of the variation in boys PA (8.4%) but not girls. Girls compared to boys had less favourable individual attributes associated with PA at age 8 years, including 18% lower cardio-respiratory fitness (3.5 vs 4.2, pphysical education (7.7 vs 8.4, pboys but not girls. Girls PA was less favourably influenced by socio-ecological factors at the individual, family, school and environmental levels. These factors are potentially modifiable suggesting the gap in PA between boys and girls can be reduced. Strategies aiming to increase PA should be multicomponent and take into consideration that pathways to increasing PA are likely to differ among boys and girls.

  11. Morphing Literacy: Boys Reshaping Their School-Based Literacy Practices

    Science.gov (United States)

    Blair, Heather A.; Stanford, Kathy

    2004-01-01

    Details about a two-year ethnographic case study research in middle school boys to understand school literacy are presented. The study revealed that boys resist many school-based practices by transforming the assigned literacy work.

  12. Sexual orientation disparities in eating disorder symptoms among adolescent boys and girls in the UK.

    Science.gov (United States)

    Calzo, Jerel P; Austin, S Bryn; Micali, Nadia

    2018-03-17

    Much of the research on sexual orientation disparities in eating disorder behaviors has been conducted in the USA, Canada, and Australia. Data on the associations of sexual orientation and eating disorder symptoms among adolescents in the UK are lacking. Participants were children from the Avon Longitudinal Study of Parents and Children, a youth cohort born 1991-1992 (n = 5048; 53% female; 12% sexual minority). Sexual orientation was assessed at 16 years. Eating disorder symptoms were assessed at 14 and 16 years. Multivariable regression models (adjusting for BMI, ethnicity, socioeconomic status) examined associations between sexual orientation and (1) odds of past-year purging and binge eating, and (2) mean differences in body dissatisfaction, pressure to increase muscularity (boys only), and Dutch Eating Behavior Questionnaire subscales. At age 14, gay and bisexual boys and mostly heterosexual girls reported greater body dissatisfaction than their same-gender heterosexual peers. All sexual minority boys and mostly heterosexual girls reported greater mean dysfunctional eating behaviors than their same-gender heterosexual peers. At age 16, gay and bisexual boys had 12.5 times the odds of heterosexual boys of binge eating; mostly heterosexual boys had over three times the odds of reporting binge eating. Sexual minority girls had over twice the odds of heterosexual girls of purging and binge eating. By mid-adolescence, sexual minority youth in the UK had elevated risk for eating disorder symptoms, suggesting the need for early prevention efforts.

  13. The juggling paradigm: a novel social neuroscience approach to identify neuropsychophysiological markers of team mental models.

    Science.gov (United States)

    Filho, Edson; Bertollo, Maurizio; Robazza, Claudio; Comani, Silvia

    2015-01-01

    Since the discovery of the mirror neuron system in the 1980s, little, if any, research has been devoted to the study of interactive motor tasks (Goldman, 2012). Scientists interested in the neuropsychophysiological markers of joint motor action have relied on observation paradigms and passive tasks rather than dynamic paradigms and interactive tasks (Konvalinka and Roepstorff, 2012). Within this research scenario, we introduce a novel research paradigm that uses cooperative juggling as a platform to capture peripheral (e.g., skin conductance, breathing and heart rates, electromyographic signals) and central neuropsychophysiological (e.g., functional connectivity within and between brains) markers underlying the notion of team mental models (TMM). We discuss the epistemological and theoretical grounds of a cooperative juggling paradigm, and propose testable hypotheses on neuropsychophysiological markers underlying TMM. Furthermore, we present key methodological concerns that may influence peripheral responses as well as single and hyperbrain network configurations during joint motor action. Preliminary findings of the paradigm are highlighted. We conclude by delineating avenues for future research.

  14. Constraint based modeling of metabolism allows finding metabolic cancer hallmarks and identifying personalized therapeutic windows.

    Science.gov (United States)

    Bordel, Sergio

    2018-04-13

    In order to choose optimal personalized anticancer treatments, transcriptomic data should be analyzed within the frame of biological networks. The best known human biological network (in terms of the interactions between its different components) is metabolism. Cancer cells have been known to have specific metabolic features for a long time and currently there is a growing interest in characterizing new cancer specific metabolic hallmarks. In this article it is presented a method to find personalized therapeutic windows using RNA-seq data and Genome Scale Metabolic Models. This method is implemented in the python library, pyTARG. Our predictions showed that the most anticancer selective (affecting 27 out of 34 considered cancer cell lines and only 1 out of 6 healthy mesenchymal stem cell lines) single metabolic reactions are those involved in cholesterol biosynthesis. Excluding cholesterol biosynthesis, all the considered cell lines can be selectively affected by targeting different combinations (from 1 to 5 reactions) of only 18 metabolic reactions, which suggests that a small subset of drugs or siRNAs combined in patient specific manners could be at the core of metabolism based personalized treatments.

  15. The oldest magnetic record in our solar system identified using nanometric imaging and numerical modeling.

    Science.gov (United States)

    Shah, Jay; Williams, Wyn; Almeida, Trevor P; Nagy, Lesleis; Muxworthy, Adrian R; Kovács, András; Valdez-Grijalva, Miguel A; Fabian, Karl; Russell, Sara S; Genge, Matthew J; Dunin-Borkowski, Rafal E

    2018-03-21

    Recordings of magnetic fields, thought to be crucial to our solar system's rapid accretion, are potentially retained in unaltered nanometric low-Ni kamacite (~ metallic Fe) grains encased within dusty olivine crystals, found in the chondrules of unequilibrated chondrites. However, most of these kamacite grains are magnetically non-uniform, so their ability to retain four-billion-year-old magnetic recordings cannot be estimated by previous theories, which assume only uniform magnetization. Here, we demonstrate that non-uniformly magnetized nanometric kamacite grains are stable over solar system timescales and likely the primary carrier of remanence in dusty olivine. By performing in-situ temperature-dependent nanometric magnetic measurements using off-axis electron holography, we demonstrate the thermal stability of multi-vortex kamacite grains from the chondritic Bishunpur meteorite. Combined with numerical micromagnetic modeling, we determine the stability of the magnetization of these grains. Our study shows that dusty olivine kamacite grains are capable of retaining magnetic recordings from the accreting solar system.

  16. Mixed models identify physic nut genotypes adapted to environments with different phosphorus availability.

    Science.gov (United States)

    Teodoro, P E; Laviola, B G; Martins, L D; Amaral, J F T; Rodrigues, W N

    2016-08-19

    The aim of this study was to screen physic nut (Jatropha curcas) genotypes that differ in their phosphorous (P) use, using mixed models. The experiment was conducted in a greenhouse located in the experimental area of the Centro de Ciências Agrárias of the Universidade Federal do Espírito Santo, in Alegre, ES, Brazil. The experiment was arranged in a randomized block design, using a 10 x 3-factorial scheme, including ten physic nut genotypes and two environments that differed in their levels of soil P availability (10 and 60 mg/dm 3 ), each with four replications. After 100 days of cultivation, we evaluated the plant height, stem diameter, root volume, root dry matter, aerial part dry matter, total dry matter, as well as the efficiency of absorption, and use. The parameters were estimated for combined selection while considering the studied parameters: stability and adaptability for both environments were obtained using the harmonic mean of the relative performance of the predicted genotypic values. High genotype by environment interactions were observed for most physic nut traits, indicating considerable influences of P availability on the phenotypic value. The genotype Paraíso simultaneously presented high adaptability and stability for aerial part dry matter, total dry matter, and P translocation efficiency. The genotype CNPAE-C2 showed a positive response to P fertilization by increasing both the total and aerial part dry matter.

  17. The juggling paradigm: a novel social neuroscience approach to identify neuropsychophysiological markers of team mental models

    Directory of Open Access Journals (Sweden)

    Edson eFilho

    2015-06-01

    Full Text Available Since the discovery of the mirror neuron system in the 1990s, little, if any, research has been devoted to the study of interactive motor tasks (Goldman, 2012. Scientists interested in the neuropsychophysiological markers of joint motor action have relied on observation paradigms and passive tasks rather than dynamic paradigms and interactive tasks (Konvalinka and Roepstorff, 2012. Within this research scenario, we introduce a novel research paradigm that uses cooperative juggling as a platform to capture peripheral (e.g., skin conductance, breathing and heart rates, electromyographic signals and central neuropsychophysiological (e.g., functional connectivity within and between brains markers underlying the conceptual notion of team mental models (TMM. We discuss the epistemological and theoretical grounds of a cooperative juggling paradigm, and propose testable hypotheses on neuropsychophysiological markers underlying TMM. Furthermore, we present key methodological concerns that may influence peripheral responses as well as single and hyperbrain network configurations during joint motor action. Preliminary findings of the paradigm are highlighted. We conclude by delineating avenues for future research.

  18. Spatial Interaction Modeling to Identify Potentially Exposed Populations during RDD or IND Terrorism Incidents

    International Nuclear Information System (INIS)

    Regens, J.L.; Gunter, J.T.; Gupta, S.

    2009-01-01

    Homeland Security Presidential Directive no.5 (HSPD-5) Management of Domestic Incidents and Department of Homeland Security (DHS) Planning Guidance for Protection and Recovery Following Radiological Dispersal Device (RDD) and Improvised Nuclear Device (IND) Incidents underscore the need to delineate radiological emergency guidance applicable to remedial action and recovery following an RDD or IND incident. Rapid delineation of the population potentially exposed to ionizing radiation from fallout during terrorist incidents involving RDDs or low-yield nuclear devices (≤ 20 KT) is necessary for effective medical response and incident management as part of the recovery process. This paper illustrates the application of spatial interaction models to allocate population data for a representative U.S. urban area (≅1.3M people; 1,612.27 km 2 area) at a geographical scale relevant for accurately estimating risk given dose concentrations. Estimated total dose equivalents (TEDE) are calculated for isopleths moving away from the detonation point for typical release scenarios. Population is estimated within the TEDE zones using Euclidean distances between zip code polygon centroids generated in ArcGIS version 9.1 with distance decay determined by regression analysis to apportion origin-destination pairs to a population count and density matrix on a spatial basis for daytime and night-time release scenarios. (authors)

  19. Random Forests Are Able to Identify Differences in Clotting Dynamics from Kinetic Models of Thrombin Generation.

    Science.gov (United States)

    Arumugam, Jayavel; Bukkapatnam, Satish T S; Narayanan, Krishna R; Srinivasa, Arun R

    2016-01-01

    Current methods for distinguishing acute coronary syndromes such as heart attack from stable coronary artery disease, based on the kinetics of thrombin formation, have been limited to evaluating sensitivity of well-established chemical species (e.g., thrombin) using simple quantifiers of their concentration profiles (e.g., maximum level of thrombin concentration, area under the thrombin concentration versus time curve). In order to get an improved classifier, we use a 34-protein factor clotting cascade model and convert the simulation data into a high-dimensional representation (about 19000 features) using a piecewise cubic polynomial fit. Then, we systematically find plausible assays to effectively gauge changes in acute coronary syndrome/coronary artery disease populations by introducing a statistical learning technique called Random Forests. We find that differences associated with acute coronary syndromes emerge in combinations of a handful of features. For instance, concentrations of 3 chemical species, namely, active alpha-thrombin, tissue factor-factor VIIa-factor Xa ternary complex, and intrinsic tenase complex with factor X, at specific time windows, could be used to classify acute coronary syndromes to an accuracy of about 87.2%. Such a combination could be used to efficiently assay the coagulation system.

  20. Random Forests Are Able to Identify Differences in Clotting Dynamics from Kinetic Models of Thrombin Generation.

    Directory of Open Access Journals (Sweden)

    Jayavel Arumugam

    Full Text Available Current methods for distinguishing acute coronary syndromes such as heart attack from stable coronary artery disease, based on the kinetics of thrombin formation, have been limited to evaluating sensitivity of well-established chemical species (e.g., thrombin using simple quantifiers of their concentration profiles (e.g., maximum level of thrombin concentration, area under the thrombin concentration versus time curve. In order to get an improved classifier, we use a 34-protein factor clotting cascade model and convert the simulation data into a high-dimensional representation (about 19000 features using a piecewise cubic polynomial fit. Then, we systematically find plausible assays to effectively gauge changes in acute coronary syndrome/coronary artery disease populations by introducing a statistical learning technique called Random Forests. We find that differences associated with acute coronary syndromes emerge in combinations of a handful of features. For instance, concentrations of 3 chemical species, namely, active alpha-thrombin, tissue factor-factor VIIa-factor Xa ternary complex, and intrinsic tenase complex with factor X, at specific time windows, could be used to classify acute coronary syndromes to an accuracy of about 87.2%. Such a combination could be used to efficiently assay the coagulation system.

  1. Tiny changes in local order identify the cluster formation threshold in model fluids with competing interactions.

    Science.gov (United States)

    Bomont, Jean-Marc; Costa, Dino; Bretonnet, Jean-Louis

    2017-06-14

    We use Monte Carlo simulations to carry out a thorough analysis of structural correlations arising in a relatively dense fluid of rigid spherical particles with prototype competing interactions (short-range attractive and long-range repulsive two-Yukawa model). As the attraction strength increases, we show that the local density of the fluid displays a tiny reversal of trend within specific ranges of interparticle distances, whereupon it decreases first and increases afterwards, passing through a local minimum. Particles involved in this trend display, accordingly, distinct behaviours: for a sufficiently weak attraction, they seem to contribute to the long-wave oscillations typically heralding the formation of patterns in such fluids; for a stronger attraction, after the reversal of the local density has occurred, they form an outer shell of neighbours stabilizing the existing aggregation seeds. Following the increment of attraction, precisely in correspondence of the local density reversal, the local peak developed in the structure factor at small wavevectors markedly rises, signalling-in agreement with recent structural criteria-the onset of a clustered state. A detailed cluster analysis of microscopic configurations fully validates this picture.

  2. Achondroplasia and enchondromatosis: report of three boys

    Energy Technology Data Exchange (ETDEWEB)

    Numakura, Chikahiko [Yamagata University School of Medicine, Department of Pediatrics, Yamagata (Japan); Tokyo Metropolitan Kiyose Children' s Hospital, Endocrinology and Metabolism Unit, Tokyo (Japan); Kobayashi, Hironori [Shimane University School of Medicine, Department of Pediatrics, Shimane (Japan); Hasegawa, Yukihiro [Tokyo Metropolitan Kiyose Children' s Hospital, Endocrinology and Metabolism Unit, Tokyo (Japan); Adachi, Masanori [Kanagawa Children' s Medical Center, Department of Endocrinology and Metabolism, Clinical Research Institute, Kanagawa (Japan); Kim, Ok Hwa [Ajou University Hospital, Department of Radiology, Seoul (Korea); Nishimura, Gen [Tokyo Metropolitan Kiyose Children' s Hospital, Department of Radiology, Tokyo (Japan)

    2007-06-15

    We report on three boys suffering from achondroplasia concurrent with enchondromatosis-like metaphyseal changes. Two boys who were examined by molecular analysis harbored a mutation of FGFR3, which occurs in most achondroplastic individuals. Given the prevalence of achondroplasia and enchondromatosis, the metaphyseal changes in these patients are less likely to represent the coincidence of both disorders, but rather to result from a rare consequence of the FGFR3 mutation. Impaired FGFs/FGFR3 signaling pathway in achondroplasia inhibits chondrocytic proliferation, which accounts for most characteristics of achondroplasia. On the other hand, it causes conflicting biological consequences that can suppress or stimulate chondrocytic maturation. In a small subset of achondroplastic individuals, the suppression of chondrocytic maturation may outweigh the stimulation, which leads to cartilaginous overgrowth into the metaphysis, eventually causing the metaphyseal dysplasia found in the present patients. (orig.)

  3. Achondroplasia and enchondromatosis: report of three boys

    International Nuclear Information System (INIS)

    Numakura, Chikahiko; Kobayashi, Hironori; Hasegawa, Yukihiro; Adachi, Masanori; Kim, Ok Hwa; Nishimura, Gen

    2007-01-01

    We report on three boys suffering from achondroplasia concurrent with enchondromatosis-like metaphyseal changes. Two boys who were examined by molecular analysis harbored a mutation of FGFR3, which occurs in most achondroplastic individuals. Given the prevalence of achondroplasia and enchondromatosis, the metaphyseal changes in these patients are less likely to represent the coincidence of both disorders, but rather to result from a rare consequence of the FGFR3 mutation. Impaired FGFs/FGFR3 signaling pathway in achondroplasia inhibits chondrocytic proliferation, which accounts for most characteristics of achondroplasia. On the other hand, it causes conflicting biological consequences that can suppress or stimulate chondrocytic maturation. In a small subset of achondroplastic individuals, the suppression of chondrocytic maturation may outweigh the stimulation, which leads to cartilaginous overgrowth into the metaphysis, eventually causing the metaphyseal dysplasia found in the present patients. (orig.)

  4. Netduino home automation projects for lazy boys

    CERN Document Server

    Cavanagh, Matt

    2013-01-01

    Netduino Home Automation Projects for Lazy Boys is written in a practical and friendly style. Reading this book will be an experience full of fun and learning as well.This book is ideally suited for someone who is interested in home automation, has some experience in C#, and has used a Netduino before but wants to explore more advanced topics. However, the book starts from the very basics so it can be picked up even by novices.

  5. Modelling elderly cardiac patients decision making using Cognitive Work Analysis: identifying requirements for patient decision aids.

    Science.gov (United States)

    Dhukaram, Anandhi Vivekanandan; Baber, Chris

    2015-06-01

    Patients make various healthcare decisions on a daily basis. Such day-to-day decision making can have significant consequences on their own health, treatment, care, and costs. While decision aids (DAs) provide effective support in enhancing patient's decision making, to date there have been few studies examining patient's decision making process or exploring how the understanding of such decision processes can aid in extracting requirements for the design of DAs. This paper applies Cognitive Work Analysis (CWA) to analyse patient's decision making in order to inform requirements for supporting self-care decision making. This study uses focus groups to elicit information from elderly cardiovascular disease (CVD) patients concerning a range of decision situations they face on a daily basis. Specifically, the focus groups addressed issues related to the decision making of CVD in terms of medication compliance, pain, diet and exercise. The results of these focus groups are used to develop high level views using CWA. CWA framework decomposes the complex decision making problem to inform three approaches to DA design: one design based on high level requirements; one based on a normative model of decision-making for patients; and the third based on a range of heuristics that patients seem to use. CWA helps in extracting and synthesising decision making from different perspectives: decision processes, work organisation, patient competencies and strategies used in decision making. As decision making can be influenced by human behaviour like skills, rules and knowledge, it is argued that patients require support to different types of decision making. This paper also provides insights for designers in using CWA framework for the design of effective DAs to support patients in self-management. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. The hierarchy-by-interval approach to identifying important models that need improvement in severe-accident simulation codes

    International Nuclear Information System (INIS)

    Heames, T.J.; Khatib-Rahbar, M.; Kelly, J.E.

    1995-01-01

    The hierarchy-by-interval (HBI) methodology was developed to determine an appropriate phenomena identification and ranking table for an independent peer review of severe-accident computer codes. The methodology is described, and the results of a specific code review are presented. Use of this systematic and structured approach ensures that important code models that need improvement are identified and prioritized, which allows code sponsors to more effectively direct limited resources in future code development. In addition, critical phenomenological areas that need more fundamental work, such as experimentation, are identified

  7. A microcomputer-based model for identifying urban and suburban roadways with critical large truck accident rates

    International Nuclear Information System (INIS)

    Brogan, J.D.; Cashwell, J.W.

    1992-01-01

    This paper presents an overview of techniques for merging highway accident record and roadway inventory files and employing the combined data set to identify spots or sections on highway facilities in urban and suburban areas with unusually high large truck accident rates. A statistical technique, the rate/quality control method, is used to calculate a critical rate for each location of interest. This critical rate may then be compared to the location's actual accident rate to identify locations for further study. Model enhancements and modifications are described to enable the technique to be employed in the evaluation of routing alternatives for the transport of radioactive material

  8. [Psychosocial disadvantages in incarcerated girls and boys].

    Science.gov (United States)

    Plattner, Belinda; Bessler, Cornelia; Vogt, Gunnar; Linhart, Susanne; Thun-Hohenstein, Leonhard; Aebi, Marcel

    2016-01-01

    Longitudinal studies found that criminal behavior in juveniles often concurs with neighborhood disadvantage and family dysfunction, especially in girls. In this study we assessed the psychosocial background in incarcerated juveniles and analyzed the data for each gender separately. The Multidimensional Clinical Screening Inventory for delinquent juveniles (MCSI) was used to assess school history, psychiatric history, family background, abuse and neglect and motive for crime. The sample consisted of 294 juveniles (46 females and 248 males). Innerfamilial abuse/neglect was reported by 91% (girls) and 79% (boys). 76% (girls) and 88% (boys) reported school-problems. 57% (girls) and 29% (boys) reported to have recieved psychiatric pretreatment. In girls we found significantly higher prevalence rates for parental divorce, incarceration of mother, abuse/neglect and psychiatric pretreatment. Significantly more girls reported a co-occurrence of school-problems and experiences of separation and loss and abuse (65.2% vs. 46.4%, χ²=5.51, df=1, p<.05). Incarcerated juveniles, especially females, are and have been exposed to multiple psychosocial burdens. Therefore it is necessary to implement prevention programs for psychosocially stressed families. Forensic intervention in and after detention has to include a family centered approach.

  9. Boys in India challenge gender stereotypes.

    Science.gov (United States)

    1998-01-01

    This article discusses CEDPA's Better Life Options Program in India. The program was initiated in 1987 to challenge gender inequities. The program offers over 400,000 girls a chance to develop skills and self-confidence for increasing their options in education, social mobility, work, health, and family and community roles. CEDPA's partner, Prerana, offers an integrated program that provides literacy training, vocational skills, after-school tutoring, health education, and family life education for about 600 girls/year. Vocational training includes nontraditional skills, such as video production and electronics. Prerana established a parallel program in 1994 for boys and young men that aims to change attitudes about girls and women and traditional gender roles. The program offers vocational skills, such as cooking and candle-making. Family life education teaches gender awareness and provides counseling and services for reproductive health. The Prerana program emphasizes men's shared responsibility in parenthood and sexual behavior, shared contribution to family income, health and nutrition, and prevention of violence against women. Since 1994, the program has included 1200 boys in 6 villages in New Delhi. Boys' enrollment is increasing; several young men have volunteered to become depot holders of contraceptive supplies in their villages. For example, one young man who was part of the Prerana program went on to be a depot holder and then a family planning promoter and counselor. He interacts with both young and older men. His contributions were well received by his village.

  10. Boys' Friendships during Adolescence: Intimacy, Desire, and Loss

    Science.gov (United States)

    Way, Niobe

    2013-01-01

    Longitudinal, mixed method research on friendships, conducted over the past two decades with Black, Latino, Asian, and European American boys, reveals three themes: (1) the importance for boys of being able to share their secrets with their close friends; (2) the importance of close friendships for boys' mental health; and (3) the loss of but…

  11. The Psychoeducational Profile of Boys with Klinefelter Syndrome.

    Science.gov (United States)

    Rovet, Joanne; And Others

    1996-01-01

    This article integrates the literature on intelligence and achievement outcomes in boys with Klinefelter syndrome (KS). It reports results of a study following 36 boys with KS and 33 sibling controls. Boys with KS demonstrated verbal cognitive deficits and significant underachievement in reading, spelling, and arithmetic, which increased with age.…

  12. Finiteness Marking in Boys with Fragile X Syndrome

    Science.gov (United States)

    Sterling, Audra M.; Rice, Mabel L.; Warren, Steven F.

    2012-01-01

    Purpose: The current study investigated finiteness marking (e.g., he walk "s", he walk "ed") in boys with fragile X syndrome (FXS); the boys were grouped based on receptive vocabulary (i.e., borderline, impaired). Method: Twenty-one boys with the full mutation of fragile X, between the ages of 8 and 16 years participated. The…

  13. On finding and using identifiable parameter combinations in nonlinear dynamic systems biology models and COMBOS: a novel web implementation.

    Science.gov (United States)

    Meshkat, Nicolette; Kuo, Christine Er-zhen; DiStefano, Joseph

    2014-01-01

    Parameter identifiability problems can plague biomodelers when they reach the quantification stage of development, even for relatively simple models. Structural identifiability (SI) is the primary question, usually understood as knowing which of P unknown biomodel parameters p1,…, pi,…, pP are-and which are not-quantifiable in principle from particular input-output (I-O) biodata. It is not widely appreciated that the same database also can provide quantitative information about the structurally unidentifiable (not quantifiable) subset, in the form of explicit algebraic relationships among unidentifiable pi. Importantly, this is a first step toward finding what else is needed to quantify particular unidentifiable parameters of interest from new I-O experiments. We further develop, implement and exemplify novel algorithms that address and solve the SI problem for a practical class of ordinary differential equation (ODE) systems biology models, as a user-friendly and universally-accessible web application (app)-COMBOS. Users provide the structural ODE and output measurement models in one of two standard forms to a remote server via their web browser. COMBOS provides a list of uniquely and non-uniquely SI model parameters, and-importantly-the combinations of parameters not individually SI. If non-uniquely SI, it also provides the maximum number of different solutions, with important practical implications. The behind-the-scenes symbolic differential algebra algorithms are based on computing Gröbner bases of model attributes established after some algebraic transformations, using the computer-algebra system Maxima. COMBOS was developed for facile instructional and research use as well as modeling. We use it in the classroom to illustrate SI analysis; and have simplified complex models of tumor suppressor p53 and hormone regulation, based on explicit computation of parameter combinations. It's illustrated and validated here for models of moderate complexity, with

  14. Evaluation of current prediction models for Lynch syndrome: updating the PREMM5 model to identify PMS2 mutation carriers

    NARCIS (Netherlands)

    A. Goverde (Anne); M.C.W. Spaander (Manon); D. Nieboer (Daan); A.M.W. van den Ouweland (Ans); W.N.M. Dinjens (Winand); H.J. Dubbink (Erik Jan); C. Tops (Cmj); S.W. Ten Broeke (Sanne W.); M.J. Bruno (Marco); R.M.W. Hofstra (Robert); E.W. Steyerberg (Ewout); A. Wagner (Anja)

    2017-01-01

    textabstractUntil recently, no prediction models for Lynch syndrome (LS) had been validated for PMS2 mutation carriers. We aimed to evaluate MMRpredict and PREMM5 in a clinical cohort and for PMS2 mutation carriers specifically. In a retrospective, clinic-based cohort we calculated predictions for

  15. A multi-timescale estimator for battery state of charge and capacity dual estimation based on an online identified model

    International Nuclear Information System (INIS)

    Wei, Zhongbao; Zhao, Jiyun; Ji, Dongxu; Tseng, King Jet

    2017-01-01

    Highlights: •SOC and capacity are dually estimated with online adapted battery model. •Model identification and state dual estimate are fully decoupled. •Multiple timescales are used to improve estimation accuracy and stability. •The proposed method is verified with lab-scale experiments. •The proposed method is applicable to different battery chemistries. -- Abstract: Reliable online estimation of state of charge (SOC) and capacity is critically important for the battery management system (BMS). This paper presents a multi-timescale method for dual estimation of SOC and capacity with an online identified battery model. The model parameter estimator and the dual estimator are fully decoupled and executed with different timescales to improve the model accuracy and stability. Specifically, the model parameters are online adapted with the vector-type recursive least squares (VRLS) to address the different variation rates of them. Based on the online adapted battery model, the Kalman filter (KF)-based SOC estimator and RLS-based capacity estimator are formulated and integrated in the form of dual estimation. Experimental results suggest that the proposed method estimates the model parameters, SOC, and capacity in real time with fast convergence and high accuracy. Experiments on both lithium-ion battery and vanadium redox flow battery (VRB) verify the generality of the proposed method on multiple battery chemistries. The proposed method is also compared with other existing methods on the computational cost to reveal its superiority for practical application.

  16. Integrating modelling and phenotyping approaches to identify and screen complex traits - Illustration for transpiration efficiency in cereals.

    Science.gov (United States)

    Chenu, K; van Oosterom, E J; McLean, G; Deifel, K S; Fletcher, A; Geetika, G; Tirfessa, A; Mace, E S; Jordan, D R; Sulman, R; Hammer, G L

    2018-02-21

    Following advances in genetics, genomics, and phenotyping, trait selection in breeding is limited by our ability to understand interactions within the plants and with their environments, and to target traits of most relevance for the target population of environments. We propose an integrated approach that combines insights from crop modelling, physiology, genetics, and breeding to identify traits valuable for yield gain in the target population of environments, develop relevant high-throughput phenotyping platforms, and identify genetic controls and their values in production environments. This paper uses transpiration efficiency (biomass produced per unit of water used) as an example of a complex trait of interest to illustrate how the approach can guide modelling, phenotyping, and selection in a breeding program. We believe that this approach, by integrating insights from diverse disciplines, can increase the resource use efficiency of breeding programs for improving yield gains in target populations of environments.

  17. Modeling Aerobic Carbon Source Degradation Processes using Titrimetric Data and Combined Respirometric-Titrimetric Data: Structural and Practical Identifiability

    DEFF Research Database (Denmark)

    Gernaey, Krist; Petersen, B.; Dochain, D.

    2002-01-01

    The structural and practical identifiability of a model for description of respirometric-titrimetric data derived from aerobic batch substrate degradation experiments of a CxHyOz carbon source with activated sludge was evaluated. The model processes needed to describe titrimetric data included su...... the initial substrate concentration S-S(O) is known. The values found correspond to values reported in literature, but, interestingly, also seem able to reflect the occurrence of storage processes when pulses of acetate and dextrose are added. (C) 2002 Wiley Periodicals, Inc....

  18. Promoter-enhancer interactions identified from Hi-C data using probabilistic models and hierarchical topological domains.

    Science.gov (United States)

    Ron, Gil; Globerson, Yuval; Moran, Dror; Kaplan, Tommy

    2017-12-21

    Proximity-ligation methods such as Hi-C allow us to map physical DNA-DNA interactions along the genome, and reveal its organization into topologically associating domains (TADs). As the Hi-C data accumulate, computational methods were developed for identifying domain borders in multiple cell types and organisms. Here, we present PSYCHIC, a computational approach for analyzing Hi-C data and identifying promoter-enhancer interactions. We use a unified probabilistic model to segment the genome into domains, which we then merge hierarchically and fit using a local background model, allowing us to identify over-represented DNA-DNA interactions across the genome. By analyzing the published Hi-C data sets in human and mouse, we identify hundreds of thousands of putative enhancers and their target genes, and compile an extensive genome-wide catalog of gene regulation in human and mouse. As we show, our predictions are highly enriched for ChIP-seq and DNA accessibility data, evolutionary conservation, eQTLs and other DNA-DNA interaction data.

  19. Identifying extensions required by RUP (Rational Unified Process) to comply with CMM (Capability Maturity Model) levels 2 and 3

    OpenAIRE

    Manzoni, Lisandra Vielmo; Price, Roberto Tom

    2003-01-01

    This paper describes an assessment of the Rational Unified Process (RUP) based on the Capability Maturity Model (CMM). For each key practice (KP) identified in each key process area (KPA) of CMM levels 2 and 3, the Rational Unified Process was assessed to determine whether it satisfied the KP or not. For each KPA, the percentage of the key practices supported was calculated, and the results were tabulated. The report includes considerations about the coverage of each key process area, describ...

  20. Systemic Thinking and Requisite Holism in Mastering Logistics Risks: the Model for Identifying Risks in Organisations and Supply Chain

    OpenAIRE

    Borut Jereb; Teodora Ivanuša; Bojan Rosi

    2013-01-01

    Risks in logistic processes represent one of the major issues in supply chain management nowadays. Every organization strives for success, and uninterrupted operations are the key factors in achieving this goal, which cannot be achieved without efficient risk management. In the scope of supply chain risk research, we identified some key issues in the field, the major issue being the lack of standardization and models, which can make risk management in an organization easier and more efficient...

  1. The Boy Problem: Many Boys Think School Is Stupid and Reading Stinks--Is There a Remedy?

    Science.gov (United States)

    Sax, Leonard

    2007-01-01

    The gender issue is relevant to classroom learning in more ways than one. Increasingly in the United States, young boys are saying that school is stupid and they do not like to read. This phenomenon cuts across all demographic groups: it affects affluent white boys in the suburbs no less than it affects black boys in low-income neighborhoods. In…

  2. Genome-wide significant localization for working and spatial memory: Identifying genes for psychosis using models of cognition.

    Science.gov (United States)

    Knowles, Emma E M; Carless, Melanie A; de Almeida, Marcio A A; Curran, Joanne E; McKay, D Reese; Sprooten, Emma; Dyer, Thomas D; Göring, Harald H; Olvera, Rene; Fox, Peter; Almasy, Laura; Duggirala, Ravi; Kent, Jack W; Blangero, John; Glahn, David C

    2014-01-01

    It is well established that risk for developing psychosis is largely mediated by the influence of genes, but identifying precisely which genes underlie that risk has been problematic. Focusing on endophenotypes, rather than illness risk, is one solution to this problem. Impaired cognition is a well-established endophenotype of psychosis. Here we aimed to characterize the genetic architecture of cognition using phenotypically detailed models as opposed to relying on general IQ or individual neuropsychological measures. In so doing we hoped to identify genes that mediate cognitive ability, which might also contribute to psychosis risk. Hierarchical factor models of genetically clustered cognitive traits were subjected to linkage analysis followed by QTL region-specific association analyses in a sample of 1,269 Mexican American individuals from extended pedigrees. We identified four genome wide significant QTLs, two for working and two for spatial memory, and a number of plausible and interesting candidate genes. The creation of detailed models of cognition seemingly enhanced the power to detect genetic effects on cognition and provided a number of possible candidate genes for psychosis. © 2013 Wiley Periodicals, Inc.

  3. Inverse modelling of fluvial sediment connectivity identifies characteristics and spatial distribution of sediment sources in a large river network.

    Science.gov (United States)

    Schmitt, R. J. P.; Bizzi, S.; Kondolf, G. M.; Rubin, Z.; Castelletti, A.

    2016-12-01

    Field and laboratory evidence indicates that the spatial distribution of transport in both alluvial and bedrock rivers is an adaptation to sediment supply. Sediment supply, in turn, depends on spatial distribution and properties (e.g., grain sizes and supply rates) of individual sediment sources. Analyzing the distribution of transport capacity in a river network could hence clarify the spatial distribution and properties of sediment sources. Yet, challenges include a) identifying magnitude and spatial distribution of transport capacity for each of multiple grain sizes being simultaneously transported, and b) estimating source grain sizes and supply rates, both at network scales. Herein, we approach the problem of identifying the spatial distribution of sediment sources and the resulting network sediment fluxes in a major, poorly monitored tributary (80,000 km2) of the Mekong. Therefore, we apply the CASCADE modeling framework (Schmitt et al. (2016)). CASCADE calculates transport capacities and sediment fluxes for multiple grainsizes on the network scale based on remotely-sensed morphology and modelled hydrology. CASCADE is run in an inverse Monte Carlo approach for 7500 random initializations of source grain sizes. In all runs, supply of each source is inferred from the minimum downstream transport capacity for the source grain size. Results for each realization are compared to sparse available sedimentary records. Only 1 % of initializations reproduced the sedimentary record. Results for these realizations revealed a spatial pattern in source supply rates, grain sizes, and network sediment fluxes that correlated well with map-derived patterns in lithology and river-morphology. Hence, we propose that observable river hydro-morphology contains information on upstream source properties that can be back-calculated using an inverse modeling approach. Such an approach could be coupled to more detailed models of hillslope processes in future to derive integrated models

  4. Machine learning models identify molecules active against the Ebola virus in vitro [version 3; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Sean Ekins

    2017-01-01

    Full Text Available The search for small molecule inhibitors of Ebola virus (EBOV has led to several high throughput screens over the past 3 years. These have identified a range of FDA-approved active pharmaceutical ingredients (APIs with anti-EBOV activity in vitro and several of which are also active in a mouse infection model. There are millions of additional commercially-available molecules that could be screened for potential activities as anti-EBOV compounds. One way to prioritize compounds for testing is to generate computational models based on the high throughput screening data and then virtually screen compound libraries. In the current study, we have generated Bayesian machine learning models with viral pseudotype entry assay and the EBOV replication assay data. We have validated the models internally and externally. We have also used these models to computationally score the MicroSource library of drugs to select those likely to be potential inhibitors. Three of the highest scoring molecules that were not in the model training sets, quinacrine, pyronaridine and tilorone, were tested in vitro and had EC50 values of 350, 420 and 230 nM, respectively. Pyronaridine is a component of a combination therapy for malaria that was recently approved by the European Medicines Agency, which may make it more readily accessible for clinical testing. Like other known antimalarial drugs active against EBOV, it shares the 4-aminoquinoline scaffold. Tilorone, is an investigational antiviral agent that has shown a broad array of biological activities including cell growth inhibition in cancer cells, antifibrotic properties, α7 nicotinic receptor agonist activity, radioprotective activity and activation of hypoxia inducible factor-1. Quinacrine is an antimalarial but also has use as an anthelmintic. Our results suggest data sets with less than 1,000 molecules can produce validated machine learning models that can in turn be utilized to identify novel EBOV inhibitors in

  5. Machine learning models identify molecules active against the Ebola virus in vitro [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Sean Ekins

    2015-10-01

    Full Text Available The search for small molecule inhibitors of Ebola virus (EBOV has led to several high throughput screens over the past 3 years. These have identified a range of FDA-approved active pharmaceutical ingredients (APIs with anti-EBOV activity in vitro and several of which are also active in a mouse infection model. There are millions of additional commercially-available molecules that could be screened for potential activities as anti-EBOV compounds. One way to prioritize compounds for testing is to generate computational models based on the high throughput screening data and then virtually screen compound libraries. In the current study, we have generated Bayesian machine learning models with viral pseudotype entry assay and the EBOV replication assay data. We have validated the models internally and externally. We have also used these models to computationally score the MicroSource library of drugs to select those likely to be potential inhibitors. Three of the highest scoring molecules that were not in the model training sets, quinacrine, pyronaridine and tilorone, were tested in vitro and had EC50 values of 350, 420 and 230 nM, respectively. Pyronaridine is a component of a combination therapy for malaria that was recently approved by the European Medicines Agency, which may make it more readily accessible for clinical testing. Like other known antimalarial drugs active against EBOV, it shares the 4-aminoquinoline scaffold. Tilorone, is an investigational antiviral agent that has shown a broad array of biological activities including cell growth inhibition in cancer cells, antifibrotic properties, α7 nicotinic receptor agonist activity, radioprotective activity and activation of hypoxia inducible factor-1. Quinacrine is an antimalarial but also has use as an anthelmintic. Our results suggest data sets with less than 1,000 molecules can produce validated machine learning models that can in turn be utilized to identify novel EBOV inhibitors in

  6. Machine learning models identify molecules active against the Ebola virus in vitro [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Sean Ekins

    2016-01-01

    Full Text Available The search for small molecule inhibitors of Ebola virus (EBOV has led to several high throughput screens over the past 3 years. These have identified a range of FDA-approved active pharmaceutical ingredients (APIs with anti-EBOV activity in vitro and several of which are also active in a mouse infection model. There are millions of additional commercially-available molecules that could be screened for potential activities as anti-EBOV compounds. One way to prioritize compounds for testing is to generate computational models based on the high throughput screening data and then virtually screen compound libraries. In the current study, we have generated Bayesian machine learning models with viral pseudotype entry assay and the EBOV replication assay data. We have validated the models internally and externally. We have also used these models to computationally score the MicroSource library of drugs to select those likely to be potential inhibitors. Three of the highest scoring molecules that were not in the model training sets, quinacrine, pyronaridine and tilorone, were tested in vitro and had EC50 values of 350, 420 and 230 nM, respectively. Pyronaridine is a component of a combination therapy for malaria that was recently approved by the European Medicines Agency, which may make it more readily accessible for clinical testing. Like other known antimalarial drugs active against EBOV, it shares the 4-aminoquinoline scaffold. Tilorone, is an investigational antiviral agent that has shown a broad array of biological activities including cell growth inhibition in cancer cells, antifibrotic properties, α7 nicotinic receptor agonist activity, radioprotective activity and activation of hypoxia inducible factor-1. Quinacrine is an antimalarial but also has use as an anthelmintic. Our results suggest data sets with less than 1,000 molecules can produce validated machine learning models that can in turn be utilized to identify novel EBOV inhibitors in

  7. Global sensitivity analysis for identifying important parameters of nitrogen nitrification and denitrification under model uncertainty and scenario uncertainty

    Science.gov (United States)

    Chen, Zhuowei; Shi, Liangsheng; Ye, Ming; Zhu, Yan; Yang, Jinzhong

    2018-06-01

    Nitrogen reactive transport modeling is subject to uncertainty in model parameters, structures, and scenarios. By using a new variance-based global sensitivity analysis method, this paper identifies important parameters for nitrogen reactive transport with simultaneous consideration of these three uncertainties. A combination of three scenarios of soil temperature and two scenarios of soil moisture creates a total of six scenarios. Four alternative models describing the effect of soil temperature and moisture content are used to evaluate the reduction functions used for calculating actual reaction rates. The results show that for nitrogen reactive transport problem, parameter importance varies substantially among different models and scenarios. Denitrification and nitrification process is sensitive to soil moisture content status rather than to the moisture function parameter. Nitrification process becomes more important at low moisture content and low temperature. However, the changing importance of nitrification activity with respect to temperature change highly relies on the selected model. Model-averaging is suggested to assess the nitrification (or denitrification) contribution by reducing the possible model error. Despite the introduction of biochemical heterogeneity or not, fairly consistent parameter importance rank is obtained in this study: optimal denitrification rate (Kden) is the most important parameter; reference temperature (Tr) is more important than temperature coefficient (Q10); empirical constant in moisture response function (m) is the least important one. Vertical distribution of soil moisture but not temperature plays predominant role controlling nitrogen reaction. This study provides insight into the nitrogen reactive transport modeling and demonstrates an effective strategy of selecting the important parameters when future temperature and soil moisture carry uncertainties or when modelers face with multiple ways of establishing nitrogen

  8. Systemic Thinking and Requisite Holism in Mastering Logistics Risks: the Model for Identifying Risks in Organisations and Supply Chain

    Directory of Open Access Journals (Sweden)

    Bojan Rosi

    2013-02-01

    Full Text Available Risks in logistic processes represent one of the major issues in supply chain management nowadays. Every organization strives for success, and uninterrupted operations are the key factors in achieving this goal, which cannot be achieved without efficient risk management. In the scope of supply chain risk research, we identified some key issues in the field, the major issue being the lack of standardization and models, which can make risk management in an organization easier and more efficient. Consequently, we developed a model, which captures and identifies risks in an organization and its supply chain. It is in accordance with the general risk management standard – ISO 31000, and incorporates some relevant recent findings from general and supply chain risk management, especially from the viewpoint of public segmentation. This experimental catalogue (which is also published online can serve as a checklist and a starting point of supply chain risk management in organizations. Its main idea is cooperation between experts from the area in order to compile an ever-growing list of possible risks and to provide an insight in the model and its value in practice, for which reason input and opinions of anyone who uses our model are greatly appreciated and included in the catalogue.

  9. Identifying sources of methane sampled in the Arctic using δ13C in CH4 and Lagrangian particle dispersion modelling.

    Science.gov (United States)

    Cain, Michelle; France, James; Pyle, John; Warwick, Nicola; Fisher, Rebecca; Lowry, Dave; Allen, Grant; O'Shea, Sebastian; Illingworth, Samuel; Jones, Ben; Gallagher, Martin; Welpott, Axel; Muller, Jennifer; Bauguitte, Stephane; George, Charles; Hayman, Garry; Manning, Alistair; Myhre, Catherine Lund; Lanoisellé, Mathias; Nisbet, Euan

    2016-04-01

    An airmass of enhanced methane was sampled during a research flight at ~600 m to ~2000 m altitude between the North coast of Norway and Svalbard on 21 July 2012. The largest source of methane in the summertime Arctic is wetland emissions. Did this enhancement in methane come from wetland emissions? The airmass was identified through continuous methane measurements using a Los Gatos fast greenhouse gas analyser on board the UK's BAe-146 Atmospheric Research Aircraft (ARA) as part of the MAMM (Methane in the Arctic: Measurements and Modelling) campaign. A Lagrangian particle dispersion model (the UK Met Office's NAME model) was run backwards to identify potential methane source regions. This was combined with a methane emission inventory to create "pseudo observations" to compare with the aircraft observations. This modelling was used to constrain the δ13C CH4 wetland source signature (where δ13C CH4 is the ratio of 13C to 12C in methane), resulting in a most likely signature of -73‰ (±4‰7‰). The NAME back trajectories suggest a methane source region of north-western Russian wetlands, and -73‰ is consistent with in situ measurements of wetland methane at similar latitudes in Scandinavia. This analysis has allowed us to study emissions from remote regions for which we do not have in situ observations, giving us an extra tool in the determination of the isotopic source variation of global methane emissions.

  10. [A successful attempt with a consulting service for boys].

    Science.gov (United States)

    Gottlieb, C; Christiansen, I; Von Segebaden, C; Wiksten-Almströmer, M

    1998-08-05

    As adolescence is a critical period of development, and as boys are less inclined than girls to approach the school facility for adolescent counselling, segregated consulting hours were introduced for boys to attract those with problems. The frequency of consultations by boys increased by 25 per cent, and 70 per cent of the boys reported a preference for the segregated consulting hours; 75 per cent appreciated the absence of girls from the waiting room; and of the 42 per cent with special preferences regarding the gender of the staff encountered, half reported preferring a man. Most of the boys presented with defined problems, though many revealed other problems, often relating to sexuality, in the course of consultation. The availability of segregated consulting hours for boys with adolescent problems is important, and often the only way to reach young boys who need help.

  11. Overdiagnosis of ADHD in boys: Stereotype impact on neuropsychological assessment.

    Science.gov (United States)

    Fresson, Megan; Meulemans, Thierry; Dardenne, Benoit; Geurten, Marie

    2018-02-12

    There is vigorous debate regarding the possibility that ADHD is overdiagnosed in boys. We investigated the impact of the gender stereotype depicting boys as inattentive and impulsive on neuropsychological assessment (observation of psychology students and child's cognitive performance). In experiment 1, after the stereotype was activated, psychology students rated a "boy," a "girl," or a "child" on a behavioral assessment scale. In experiment 2, 103 children (boys and girls) completed neuropsychological tasks under stereotype threat or neutral conditions. The gender stereotype led psychology students to assess a child's behaviors more negatively if they thought the child was a boy. Boys' performance on one cognitive score declined following stereotype threat. Regression path analyses suggested moderation by stigma consciousness. Additionally, there were mediating and suppressing (through stereotype endorsement) effects. Our results suggest that the gender stereotype might contribute to the overdiagnosis of ADHD in boys.

  12. The Repudiation of Single-Sex Education: Boys' Schools in the Soviet Union, 1943-1954

    Science.gov (United States)

    Ewing, E. Thomas

    2006-01-01

    This article examines the 11-year Soviet experiment with boys' schools as a way to cast new light on scholarly research and public debates about single-sex education. Drawing on archival and published materials by educators who described school conditions, identified problems, suggested reforms, and evaluated remedies, the author argues that…

  13. Implications of Boy Scout group use of public lands for natural resource managers: a regional comparison

    Science.gov (United States)

    Gail A. Vander Stoep

    1992-01-01

    Resource managers can apply group-specific rather than generic communications and management strategies to different public land user groups. This study compares use patterns of one user group, Boy Scout troops, from two regions of the United States. It identifies their public land use patterns, activities, needs, and motivations. Results can be used by resource...

  14. I wish I were a warrior: Effects of violent video games on adolescent boys

    NARCIS (Netherlands)

    Konijn, E.A.; Nije Bijvank, M.; Bushman, B.J.

    2007-01-01

    This study tested the hypothesis that violent video games are especially likely to increase aggression when players identify with violent game characters. Dutch adolescent boys with low education ability (N = 112) were randomly assigned to play a realistic or fantasy violent or nonviolent video

  15. Emo Gay Boys and Subculture: Postpunk Queer Youth and (Re)thinking Images of Masculinity

    Science.gov (United States)

    Peters, Brian M.

    2010-01-01

    This is an exploration of gay youth subculture and emo boys. The study is a mesh of findings and related theoretical understandings about gay emo subculture, masculinities, style, and alternative gay youth. This study looks at gay male teenagers who identify with emo, a movement that stems from music and aesthetics creating a particular visual for…

  16. A measurement model of perinatal stressors: identifying risk for postnatal emotional distress in mothers of high-risk infants.

    Science.gov (United States)

    DeMier, R L; Hynan, M T; Hatfield, R F; Varner, M W; Harris, H B; Manniello, R L

    2000-01-01

    A measurement model of perinatal stressors was first evaluated for reliability and then used to identify risk factors for postnatal emotional distress in high-risk mothers. In Study 1, six measures (gestational age of the baby, birthweight, length of the baby's hospitalization, a postnatal complications rating for the infant, and Apgar scores at 1 and 5 min) were obtained from chart reviews of preterm births at two different hospitals. Confirmatory factor analyses revealed that the six measures could be accounted for by three factors: (a) Infant Maturity, (b) Apgar Ratings, and (c) Complications. In Study 2, a modified measurement model indicated that Infant Maturity and Complications were significant predictors of postnatal emotional distress in an additional sample of mothers. This measurement model may also be useful in predicting (a) other measures of psychological distress in parents, and (b) measures of cognitive and motor development in infants.

  17. Prenatal phthalate exposure and reduced masculine play in boys.

    Science.gov (United States)

    Swan, S H; Liu, F; Hines, M; Kruse, R L; Wang, C; Redmon, J B; Sparks, A; Weiss, B

    2010-04-01

    Foetal exposure to antiandrogens alters androgen-sensitive development in male rodents, resulting in less male-typical behaviour. Foetal phthalate exposure is also associated with male reproductive development in humans, but neurodevelopmental outcomes have seldom been examined in relation to phthalate exposure. To assess play behaviour in relation to phthalate metabolite concentration in prenatal urine samples, we recontacted participants in the Study for Future Families whose phthalate metabolites had been measured in mid-pregnancy urine samples. Mothers completed a questionnaire including the Pre-School Activities Inventory, a validated instrument used to assess sexually dimorphic play behaviour. We examined play behaviour scores (masculine, feminine and composite) in relationship to (log(10)) phthalate metabolite concentrations in mother's urine separately for boys (N = 74) and girls (N = 71). Covariates (child's age, mother's age and education and parental attitude towards atypical play choices) were controlled using multivariate regression models. Concentrations of dibutyl phthalate metabolites, mono-n-butyl phthalate (MnBP) and mono-isobutyl phthalate (MiBP) and their sum, were associated with a decreased (less masculine) composite score in boys (regression coefficients -4.53,-3.61 and -4.20, p = 0.01, 0.07 and 0.04 for MnBP, MiBP and their sum respectively). Concentrations of two urinary metabolites of di(2-ethylhexyl) phthalate (DEHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and the sum of these DEHP metabolites plus mono(2-ethylhexyl) phthalate were associated with a decreased masculine score (regression coefficients -3.29,-2.94 and -3.18, p = 0.02, 0.04 and 0.04) for MEHHP, MEOHP and the sum respectively. No strong associations were seen between behaviour and urinary concentrations of any other phthalate metabolites in boys, or between girls' scores and any metabolites. These data, although based on

  18. Do maize models capture the impacts of heat and drought stresses on yield? Using algorithm ensembles to identify successful approaches.

    Science.gov (United States)

    Jin, Zhenong; Zhuang, Qianlai; Tan, Zeli; Dukes, Jeffrey S; Zheng, Bangyou; Melillo, Jerry M

    2016-09-01

    Stresses from heat and drought are expected to increasingly suppress crop yields, but the degree to which current models can represent these effects is uncertain. Here we evaluate the algorithms that determine impacts of heat and drought stress on maize in 16 major maize models by incorporating these algorithms into a standard model, the Agricultural Production Systems sIMulator (APSIM), and running an ensemble of simulations. Although both daily mean temperature and daylight temperature are common choice of forcing heat stress algorithms, current parameterizations in most models favor the use of daylight temperature even though the algorithm was designed for daily mean temperature. Different drought algorithms (i.e., a function of soil water content, of soil water supply to demand ratio, and of actual to potential transpiration ratio) simulated considerably different patterns of water shortage over the growing season, but nonetheless predicted similar decreases in annual yield. Using the selected combination of algorithms, our simulations show that maize yield reduction was more sensitive to drought stress than to heat stress for the US Midwest since the 1980s, and this pattern will continue under future scenarios; the influence of excessive heat will become increasingly prominent by the late 21st century. Our review of algorithms in 16 crop models suggests that the impacts of heat and drought stress on plant yield can be best described by crop models that: (i) incorporate event-based descriptions of heat and drought stress, (ii) consider the effects of nighttime warming, and (iii) coordinate the interactions among multiple stresses. Our study identifies the proficiency with which different model formulations capture the impacts of heat and drought stress on maize biomass and yield production. The framework presented here can be applied to other modeled processes and used to improve yield predictions of other crops with a wide variety of crop models. © 2016 John

  19. Electrolyzed-water generator 'SaniBoy'; Eisei jokinsuik kyokyu sochi 'SaniBoy'

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, M; Kakiuchi, H; Muto, K [Fuji Electric Co. Ltd., Tokyo (Japan)

    2000-03-10

    In the food industry, injuries due to food poisoning have been increasing. Especially the mass outbreak of food poisoning by Escherichia coli such as O-157 in 1996 gave warning on the importance of food sanitation management. Public efforts such as the Hazard Analysis and Critical Control Point (HACCP) system have been made to prevent food poisoning. Recently, disinfection made by electrolyzing water with some salt added has attracted attention. Fuji Electric has developed the generator 'SaniBoy' that produces weak alkaline electrolyzed water without wasting water. The environment-friendly 'SaniBoy' will contribute to sanitation in various fields. (author)

  20. Calibrating and Validating a Simulation Model to Identify Drivers of Urban Land Cover Change in the Baltimore, MD Metropolitan Region

    Directory of Open Access Journals (Sweden)

    Claire Jantz

    2014-09-01

    Full Text Available We build upon much of the accumulated knowledge of the widely used SLEUTH urban land change model and offer advances. First, we use SLEUTH’s exclusion/attraction layer to identify and test different urban land cover change drivers; second, we leverage SLEUTH’s self-modification capability to incorporate a demographic model; and third, we develop a validation procedure to quantify the influence of land cover change drivers and assess uncertainty. We found that, contrary to our a priori expectations, new development is not attracted to areas serviced by existing or planned water and sewer infrastructure. However, information about where population and employment growth is likely to occur did improve model performance. These findings point to the dominant role of centrifugal forces in post-industrial cities like Baltimore, MD. We successfully developed a demographic model that allowed us to constrain the SLEUTH model forecasts and address uncertainty related to the dynamic relationship between changes in population and employment and urban land use. Finally, we emphasize the importance of model validation. In this work the validation procedure played a key role in rigorously assessing the impacts of different exclusion/attraction layers and in assessing uncertainty related to population and employment forecasts.

  1. A model to identify mathematics topics in MXit lingo to provide tutors quick access to supporting documentation

    Directory of Open Access Journals (Sweden)

    Laurie Butgereit

    2011-11-01

    Full Text Available Dr MathTM is a mobile, online tutoring system where learners can use MXitTM on their mobile phones to receive help with their mathematics homework from volunteer tutors. These conversations between learners and Dr Math are held in MXit lingo. MXit lingo is a heavily abbreviated, English-like language that is evolving between users of mobile phones that communicate using MXit. The Dr Math project has been running since January 2007 and uses volunteer tutors who are mostly university students who readily understand and use MXit lingo. However, due to the large number of simultaneous conversations that the tutors are often involved in and the diversity of topics discussed, it would often be beneficial to provide assistance regarding the mathematics topic to the tutors. This article explains how the μ model identifies the mathematics topic in the conversation. The model identifies appropriate mathematics topics in just over 75% of conversations in a corpus of conversations identified to be about mathematics topics in the school curriculum.

  2. Clustering of transcriptional profiles identifies changes to insulin signaling as an early event in a mouse model of Alzheimer's disease.

    Science.gov (United States)

    Jackson, Harriet M; Soto, Ileana; Graham, Leah C; Carter, Gregory W; Howell, Gareth R

    2013-11-25

    Alzheimer's disease affects more than 35 million people worldwide but there is no known cure. Age is the strongest risk factor for Alzheimer's disease but it is not clear how age-related changes impact the disease. Here, we used a mouse model of Alzheimer's disease to identify age-specific changes that occur prior to and at the onset of traditional Alzheimer-related phenotypes including amyloid plaque formation. To identify these early events we used transcriptional profiling of mouse brains combined with computational approaches including singular value decomposition and hierarchical clustering. Our study identifies three key events in early stages of Alzheimer's disease. First, the most important drivers of Alzheimer's disease onset in these mice are age-specific changes. These include perturbations of the ribosome and oxidative phosphorylation pathways. Second, the earliest detectable disease-specific changes occur to genes commonly associated with the hypothalamic-adrenal-pituitary (HPA) axis. These include the down-regulation of genes relating to metabolism, depression and appetite. Finally, insulin signaling, in particular the down-regulation of the insulin receptor substrate 4 (Irs4) gene, may be an important event in the transition from age-related changes to Alzheimer's disease specific-changes. A combination of transcriptional profiling combined with computational analyses has uncovered novel features relevant to Alzheimer's disease in a widely used mouse model and offers avenues for further exploration into early stages of AD.

  3. Neutron dosimetry of the Little Boy device

    International Nuclear Information System (INIS)

    Pederson, R.A.; Plassmann, E.A.

    1984-01-01

    Neutron dose rates at several angular locations and at distances out to 0.5 mile have been measured during critical operation of the Little Boy replica. We used modified remmetes and thermoluminescent dosimetry techniques for the measurements. The present status of our analysis is presented including estimates of the neutron-dose-relaxation length in air and the variation of the neutron-to-gamma-ray dose ratio with distance from the replica. These results are preliminary and are subject to detector calibration measurements

  4. Sensational inventions by girls and boys

    International Nuclear Information System (INIS)

    Wang, Yeon Jung

    1999-05-01

    This book introduces the interesting and original inventions invented by girls and boys. These are the titles of the inventions : an antenna ruler, muscular strength machine with spring, items to remove sticky matter for advertisement, chair ladder for the disabled, useful control box for feeding bees, a portable carriage for dogs, a lid of ashtray, hot-air balloon using solar power, toy cannon for reports, hard badminton racket, tv cable and a distributor which are easy to install, device for car automatic parking, a cleanser for vegetables.

  5. Boys and girls who reason well mathematically.

    Science.gov (United States)

    Stanley, J C

    1993-01-01

    Since 1971 the Study of Mathematically Precocious Youth (SMPY) at Johns Hopkins University has pioneered in discovery of and provision of educational help for 12-year-old boys and girls who reason better mathematically than 99% of other 12-year-olds. SMPY originated widespread searches for such youths and special academic classes for them outside the regular school system. A regional talent search, verbal as well as mathematical, now covers all 50 states of the USA, and many varied residential summer programmes are offered across the country. These have provided educational facilitation for many thousands, and have encouraged greater curricular flexibility in schools and better articulation of in-school with out-of-school learning experiences. From the first talent search conducted by SMPY in 1972, it became obvious that boys tend to score considerably higher than girls on the College Board Scholastic Aptitude Test-Mathematical (SAT-M), a test intended mainly for college-bound 17- and 18-year-olds. This difference was reported in 1974 but attracted little attention until a controversial report in 1980 stimulated research on sex differences in various aspects of mathematics. Here I describe a study of sex differences over 10 years on 14 College Board high school achievement tests, which are taken (three usually) by bright 17- and 18-year-olds seeking admission to the USA's selective colleges and universities. Among the high scores on the European history test the ratio of males to females was greatest, 6:1. The next most sex-differentiating test was physics, 2.9:1, followed by elementary-level mathematics (mainly algebra and geometry), 2.5:1. Other ratios favouring males were, in 1991, chemistry (2.4:1), American history (2.1:1), biology (1.8:1), precalculus mathematics (1.6:1), Latin (1.6:1), French (1.4:1), modern Hebrew (1.1:1) and German (1.02:1). Tests in which more females were high scorers were literature (1.26:1), English composition (1.05:1) and Spanish (1

  6. Sensational inventions by girls and boys

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yeon Jung

    1999-05-15

    This book introduces the interesting and original inventions invented by girls and boys. These are the titles of the inventions : an antenna ruler, muscular strength machine with spring, items to remove sticky matter for advertisement, chair ladder for the disabled, useful control box for feeding bees, a portable carriage for dogs, a lid of ashtray, hot-air balloon using solar power, toy cannon for reports, hard badminton racket, tv cable and a distributor which are easy to install, device for car automatic parking, a cleanser for vegetables.

  7. Do correlates of HPV vaccine initiation differ between adolescent boys and girls?

    Science.gov (United States)

    Gilkey, Melissa B; Moss, Jennifer L; McRee, Annie-Laurie; Brewer, Noel T

    2012-09-07

    Guidelines now recommend that adolescents routinely receive human papillomavirus (HPV) vaccine. Because little is known about uptake among boys, we assessed HPV vaccine initiation in a population-based sample of adolescent boys and girls. We analyzed weighted data from 751 parents who reported on an 11- to 17-year-old son or daughter for the 2010 North Carolina Child Health Assessment and Monitoring Program survey. Stratified multivariate logistic regression analyses identified correlates of HPV vaccine initiation separately for boys and girls. Only 14% of sons had received one or more doses of HPV vaccine compared to 44% of daughters (pvaccine initiation correlated with age and having received meningococcal vaccine. Among sons, initiation of HPV vaccine was lower for those living in high income households (odds ratio [OR]=0.22, 95% CI, 0.09-0.53) and higher for those whose race was neither white nor black (OR=3.26, 95% CI, 1.06-10.04). When asked to give the main reason for not vaccinating their child against HPV, parents of unvaccinated sons were more likely than those of daughters to report not getting a provider's recommendation or not being aware that the vaccine was available for their child, but less likely to report concern about safety (pHPV vaccine. HPV vaccine correlates and concerns varied for parents of boys and girls. To improve very low levels of uptake among boys, providers should recommend HPV vaccine concomitant with other adolescent vaccines. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Big boys and little girls: gender, acculturation, and weight among young children of immigrants.

    Science.gov (United States)

    Van Hook, Jennifer; Baker, Elizabeth

    2010-06-01

    Previous research fails to find a consistent association between obesity and acculturation for children. We theorize that social isolation shelters children of immigrants from the U.S."obesiogenic" environment, but this protective effect is offset by immigrant parents' limited capacity to identify and manage this health risk in the United States. We further theorize that these factors affect boys more than girls. We use data from over 20,000 children in the Early Childhood Longitudinal Study Kindergarten Cohort and find that boys whose parents were raised outside the United States weighed more and gained weight faster than any other group. However, within this group, sons of low English-proficient parents gained weight more slowly than sons of English-proficient parents. The results thus suggest that two dimensions of low acculturation--foreign place of socialization and social iiolation--affect children's weight gain in opposite directions and are more important for boys than girls.

  9. Facial affect interpretation in boys with attention deficit/hyperactivity disorder.

    Science.gov (United States)

    Boakes, Jolee; Chapman, Elaine; Houghton, Stephen; West, John

    2008-01-01

    Recent studies have produced mixed evidence of impairments in facial affect interpretation for children with attention deficit/hyperactivity disorder (ADHD). This study investigated the presence and nature of such impairments across different stimulus formats. Twenty-four boys with ADHD and 24 age-matched comparison boys completed a 72-trial task that included facial expressions of happiness, sadness, fear, anger, surprise, and disgust. Three versions of each expression were used: a static version, a dynamic version, and a dynamic version presented within a relevant situational context. Expressions were also presented in one of two portrayal modes (cartoon versus real-life). Results indicated significant impairments for boys with ADHD on two of the six emotions (fear and disgust), which were consistent across stimulus formats. Directions for further research to identify mediating factors in the expression of such impairments in children with ADHD are discussed.

  10. Protein-protein interaction networks identify targets which rescue the MPP+ cellular model of Parkinson’s disease

    Science.gov (United States)

    Keane, Harriet; Ryan, Brent J.; Jackson, Brendan; Whitmore, Alan; Wade-Martins, Richard

    2015-11-01

    Neurodegenerative diseases are complex multifactorial disorders characterised by the interplay of many dysregulated physiological processes. As an exemplar, Parkinson’s disease (PD) involves multiple perturbed cellular functions, including mitochondrial dysfunction and autophagic dysregulation in preferentially-sensitive dopamine neurons, a selective pathophysiology recapitulated in vitro using the neurotoxin MPP+. Here we explore a network science approach for the selection of therapeutic protein targets in the cellular MPP+ model. We hypothesised that analysis of protein-protein interaction networks modelling MPP+ toxicity could identify proteins critical for mediating MPP+ toxicity. Analysis of protein-protein interaction networks constructed to model the interplay of mitochondrial dysfunction and autophagic dysregulation (key aspects of MPP+ toxicity) enabled us to identify four proteins predicted to be key for MPP+ toxicity (P62, GABARAP, GBRL1 and GBRL2). Combined, but not individual, knockdown of these proteins increased cellular susceptibility to MPP+ toxicity. Conversely, combined, but not individual, over-expression of the network targets provided rescue of MPP+ toxicity associated with the formation of autophagosome-like structures. We also found that modulation of two distinct proteins in the protein-protein interaction network was necessary and sufficient to mitigate neurotoxicity. Together, these findings validate our network science approach to multi-target identification in complex neurological diseases.

  11. Using Range-Wide Abundance Modeling to Identify Key Conservation Areas for the Micro-Endemic Bolson Tortoise (Gopherus flavomarginatus.

    Directory of Open Access Journals (Sweden)

    Cinthya A Ureña-Aranda

    Full Text Available A widespread biogeographic pattern in nature is that population abundance is not uniform across the geographic range of species: most occurrence sites have relatively low numbers, whereas a few places contain orders of magnitude more individuals. The Bolson tortoise Gopherus flavomarginatus is endemic to a small region of the Chihuahuan Desert in Mexico, where habitat deterioration threatens this species with extinction. In this study we combined field burrows counts and the approach for modeling species abundance based on calculating the distance to the niche centroid to obtain range-wide abundance estimates. For the Bolson tortoise, we found a robust, negative relationship between observed burrows abundance and distance to the niche centroid, with a predictive capacity of 71%. Based on these results we identified four priority areas for the conservation of this microendemic and threatened tortoise. We conclude that this approach may be a useful approximation for identifying key areas for sampling and conservation efforts in elusive and rare species.

  12. Integrative analysis of functional genomic annotations and sequencing data to identify rare causal variants via hierarchical modeling

    Directory of Open Access Journals (Sweden)

    Marinela eCapanu

    2015-05-01

    Full Text Available Identifying the small number of rare causal variants contributing to disease has beena major focus of investigation in recent years, but represents a formidable statisticalchallenge due to the rare frequencies with which these variants are observed. In thiscommentary we draw attention to a formal statistical framework, namely hierarchicalmodeling, to combine functional genomic annotations with sequencing data with theobjective of enhancing our ability to identify rare causal variants. Using simulations weshow that in all configurations studied, the hierarchical modeling approach has superiordiscriminatory ability compared to a recently proposed aggregate measure of deleteriousness,the Combined Annotation-Dependent Depletion (CADD score, supportingour premise that aggregate functional genomic measures can more accurately identifycausal variants when used in conjunction with sequencing data through a hierarchicalmodeling approach

  13. ApicoAP: the first computational model for identifying apicoplast-targeted proteins in multiple species of Apicomplexa.

    Directory of Open Access Journals (Sweden)

    Gokcen Cilingir

    Full Text Available Most of the parasites of the phylum Apicomplexa contain a relict prokaryotic-derived plastid called the apicoplast. This organelle is important not only for the survival of the parasite, but its unique properties make it an ideal drug target. The majority of apicoplast-associated proteins are nuclear encoded and targeted post-translationally to the organellar lumen via a bipartite signaling mechanism that requires an N-terminal signal and transit peptide (TP. Attempts to define a consensus motif that universally identifies apicoplast TPs have failed.In this study, we propose a generalized rule-based classification model to identify apicoplast-targeted proteins (ApicoTPs that use a bipartite signaling mechanism. Given a training set specific to an organism, this model, called ApicoAP, incorporates a procedure based on a genetic algorithm to tailor a discriminating rule that exploits the known characteristics of ApicoTPs. Performance of ApicoAP is evaluated for four labeled datasets of Plasmodium falciparum, Plasmodium yoelii, Babesia bovis, and Toxoplasma gondii proteins. ApicoAP improves the classification accuracy of the published dataset for P. falciparum to 94%, originally 90% using PlasmoAP.We present a parametric model for ApicoTPs and a procedure to optimize the model parameters for a given training set. A major asset of this model is that it is customizable to different parasite genomes. The ApicoAP prediction software is available at http://code.google.com/p/apicoap/ and http://bcb.eecs.wsu.edu.

  14. COMPARATIVE INDICATORS OF THE PHYSICAL DEVELOPMENT OF BOYS IN REPUBLIC OF DAGESTAN IN THE VARIOUS ECO-GEOGRAPHICAL ZONES

    Directory of Open Access Journals (Sweden)

    K. G. Kamalov

    2015-01-01

    Full Text Available Abstract:Purpose. The examination of the comparative aspect of the physical parameters of the boys in the pre - and puberty in different ecological zones (EZ of the Republic of Dagestan (RD: mountain, foothills and plains of the taxiway.Materials and Methods. The study in 3 eco-geographic zones of the Republic of Dagestan in 2641 a boy aged 11 to 17 years. Inclusion criteria were: age of onset of puberty and the completion of 11-17 years, male gender and residence in the territory (extragenital diseases. We compared the following anthropometric indicators: height, weight, body mass index.Results and conclusions. The analysing of the physical parameters of development in different areas of extragenital diseases RD identifies the following pattern: the lowest height and weight were boys living in the foothills of the taxiway. Their peers living in highland and lowland extragenital diseases taxiway growth were similar and statistically significant differences were found statistically significant differences are particularly evident with 13-14 years in boys from foothills of RD, especially when compared with their peers plain COPIES. Thus, the overall physical development of boys RD closes to those boys Russia, although the tendency to reduce them was determined. Comparative physical development of boys in various extragenital diseases RD, the worst performance demonstrated teenagers from foothill extragenital diseases.

  15. Identifying the default mode network structure using dynamic causal modeling on resting-state functional magnetic resonance imaging.

    Science.gov (United States)

    Di, Xin; Biswal, Bharat B

    2014-02-01

    The default mode network is part of the brain structure that shows higher neural activity and energy consumption when one is at rest. The key regions in the default mode network are highly interconnected as conveyed by both the white matter fiber tracing and the synchrony of resting-state functional magnetic resonance imaging signals. However, the causal information flow within the default mode network is still poorly understood. The current study used the dynamic causal modeling on a resting-state fMRI data set to identify the network structure underlying the default mode network. The endogenous brain fluctuations were explicitly modeled by Fourier series at the low frequency band of 0.01-0.08Hz, and those Fourier series were set as driving inputs of the DCM models. Model comparison procedures favored a model wherein the MPFC sends information to the PCC and the bilateral inferior parietal lobule sends information to both the PCC and MPFC. Further analyses provide evidence that the endogenous connectivity might be higher in the right hemisphere than in the left hemisphere. These data provided insight into the functions of each node in the DMN, and also validate the usage of DCM on resting-state fMRI data. © 2013.

  16. [Analysis of dietary pattern and diabetes mellitus influencing factors identified by classification tree model in adults of Fujian].

    Science.gov (United States)

    Yu, F L; Ye, Y; Yan, Y S

    2017-05-10

    Objective: To find out the dietary patterns and explore the relationship between environmental factors (especially dietary patterns) and diabetes mellitus in the adults of Fujian. Methods: Multi-stage sampling method were used to survey residents aged ≥18 years by questionnaire, physical examination and laboratory detection in 10 disease surveillance points in Fujian. Factor analysis was used to identify the dietary patterns, while logistic regression model was applied to analyze relationship between dietary patterns and diabetes mellitus, and classification tree model was adopted to identify the influencing factors for diabetes mellitus. Results: There were four dietary patterns in the population, including meat, plant, high-quality protein, and fried food and beverages patterns. The result of logistic analysis showed that plant pattern, which has higher factor loading of fresh fruit-vegetables and cereal-tubers, was a protective factor for non-diabetes mellitus. The risk of diabetes mellitus in the population at T2 and T3 levels of factor score were 0.727 (95 %CI: 0.561-0.943) times and 0.736 (95 %CI : 0.573-0.944) times higher, respectively, than those whose factor score was in lowest quartile. Thirteen influencing factors and eleven group at high-risk for diabetes mellitus were identified by classification tree model. The influencing factors were dyslipidemia, age, family history of diabetes, hypertension, physical activity, career, sex, sedentary time, abdominal adiposity, BMI, marital status, sleep time and high-quality protein pattern. Conclusion: There is a close association between dietary patterns and diabetes mellitus. It is necessary to promote healthy and reasonable diet, strengthen the monitoring and control of blood lipids, blood pressure and body weight, and have good lifestyle for the prevention and control of diabetes mellitus.

  17. Boys Growing Up: Understanding Boys' Sexual Health Education and Its Implications for Attitude Change.

    Science.gov (United States)

    Walker, B. M.; Kushner, S.

    Recent research has begun to examine heterosexual male behavior and the early experiences of masculinity. This pilot research project used naturalistic inquiry methodologies to investigate the experience and education of boys/young men in relation to matters of sexual health and masculinity and to develop an understanding of the relationship among…

  18. Salivary testosterone concentrations in pubertal ICSI boys compared with spontaneously conceived boys

    NARCIS (Netherlands)

    Belva, F.; Bonduelle, M.; Schiettecatte, J.; Tournaye, H.; Painter, R. C.; Devroey, P.; de Schepper, J.

    2011-01-01

    BACKGROUND: To date, no data exist about Leydig cell function of pubertal boys born after ICSI. To evaluate a potential risk of gonadal dysfunction in children born from fathers with compromised fertility, testicular function was assessed by the measurement of salivary testosterone. METHODS: Morning

  19. Art, Boys, and the Boy Scout Movement: Lord Baden-Powell

    Science.gov (United States)

    Chalmers, F. Graeme; Dancer, Andrea A.

    2007-01-01

    Robert Stephenson Smyth Baden-Powell (1857-1941), founder of the Boy Scout Movement in 1907, was a British military hero during the Boer War. Within an ethos and era of empire-building, athleticism, soldier-heroes and the pursuit of "manliness," Baden-Powell valued the arts and adapted his artistic skill to his wartime and Scouting activities. His…

  20. Using ensemble models to identify and apportion heavy metal pollution sources in agricultural soils on a local scale.

    Science.gov (United States)

    Wang, Qi; Xie, Zhiyi; Li, Fangbai

    2015-11-01

    This study aims to identify and apportion multi-source and multi-phase heavy metal pollution from natural and anthropogenic inputs using ensemble models that include stochastic gradient boosting (SGB) and random forest (RF) in agricultural soils on the local scale. The heavy metal pollution sources were quantitatively assessed, and the results illustrated the suitability of the ensemble models for the assessment of multi-source and multi-phase heavy metal pollution in agricultural soils on the local scale. The results of SGB and RF consistently demonstrated that anthropogenic sources contributed the most to the concentrations of Pb and Cd in agricultural soils in the study region and that SGB performed better than RF. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Modelling the existing Irish energy-system to identify future energy costs and the maximum wind penetration feasible

    DEFF Research Database (Denmark)

    Connolly, D.; Lund, Henrik; Mathiesen, Brian Vad

    2010-01-01

    energy- system to future energy costs by considering future fuel prices, CO2 prices, and different interest rates. The final investigation identifies the maximum wind penetration feasible on the 2007 Irish energy- system from a technical and economic perspective, as wind is the most promising fluctuating...... for the existing Irish energy-system is approximately 30% from both a technical and economic perspective based on 2020 energy prices. Future studies will use the model developed in this study to show that higher wind penetrations can be achieved if the existing energy-system is modified correctly. Finally...... renewable resource available in Ireland. It is concluded that the reference model simulates the Irish energy-system accurately, the annual fuel costs for Ireland’s energy could increase by approximately 58% from 2007 to 2020 if a business-as-usual scenario is followed, and the optimum wind penetration...

  2. Developing Predictive Models for Algal Bloom Occurrence and Identifying Factors Controlling their Occurrence in the Charlotte County and Surroundings

    Science.gov (United States)

    Karki, S.; Sultan, M.; Elkadiri, R.; Chouinard, K.

    2017-12-01

    Numerous occurrences of harmful algal blooms (Karenia Brevis) were reported from Southwest Florida along the coast of Charlotte County, Florida. We are developing data-driven (remote sensing, field, and meteorological data) models to accomplish the following: (1) identify the factors controlling bloom development, (2) forecast bloom occurrences, and (3) make recommendations for monitoring variables that are found to be most indicative of algal bloom occurrences and for identifying optimum locations for monitoring stations. To accomplish these three tasks we completed/are working on the following steps. Firstly, we developed an automatic system for downloading and processing of ocean color data acquired through MODIS Terra and MODIS Aqua products using SeaDAS ocean color processing software. Examples of extracted variables include: chlorophyll a (OC3M), chlorophyll a Generalized Inherent Optical Property (GIOP), chlorophyll a Garver-Siegel- Maritorena (GSM), sea surface temperature (SST), Secchi disk depth, euphotic depth, turbidity index, wind direction and speed, colored dissolved organic material (CDOM). Secondly we are developing a GIS database and a web-based GIS to host the generated remote sensing-based products in addition to relevant meteorological and field data. Examples of the meteorological and field inputs include: precipitation amount and rates, concentrations of nitrogen, phosphorous, fecal coliform and Dissolved Oxygen (DO). Thirdly, we are constructing and validating a multivariate regression model and an artificial neural network model to simulate past algal bloom occurrences using the compiled archival remote sensing, meteorological, and field data. The validated model will then be used to predict the timing and location of algal bloom occurrences. The developed system, upon completion, could enhance the decision making process, improve the citizen's quality of life, and strengthen the local economy.

  3. A data-driven modeling approach to identify disease-specific multi-organ networks driving physiological dysregulation.

    Directory of Open Access Journals (Sweden)

    Warren D Anderson

    2017-07-01

    Full Text Available Multiple physiological systems interact throughout the development of a complex disease. Knowledge of the dynamics and connectivity of interactions across physiological systems could facilitate the prevention or mitigation of organ damage underlying complex diseases, many of which are currently refractory to available therapeutics (e.g., hypertension. We studied the regulatory interactions operating within and across organs throughout disease development by integrating in vivo analysis of gene expression dynamics with a reverse engineering approach to infer data-driven dynamic network models of multi-organ gene regulatory influences. We obtained experimental data on the expression of 22 genes across five organs, over a time span that encompassed the development of autonomic nervous system dysfunction and hypertension. We pursued a unique approach for identification of continuous-time models that jointly described the dynamics and structure of multi-organ networks by estimating a sparse subset of ∼12,000 possible gene regulatory interactions. Our analyses revealed that an autonomic dysfunction-specific multi-organ sequence of gene expression activation patterns was associated with a distinct gene regulatory network. We analyzed the model structures for adaptation motifs, and identified disease-specific network motifs involving genes that exhibited aberrant temporal dynamics. Bioinformatic analyses identified disease-specific single nucleotide variants within or near transcription factor binding sites upstream of key genes implicated in maintaining physiological homeostasis. Our approach illustrates a novel framework for investigating the pathogenesis through model-based analysis of multi-organ system dynamics and network properties. Our results yielded novel candidate molecular targets driving the development of cardiovascular disease, metabolic syndrome, and immune dysfunction.

  4. HPA Axis Function Alters Development of Working Memory in Boys with FXS

    Science.gov (United States)

    Scherr, Jessica F.; Hahn, Laura J.; Hooper, Stephen R.; Hatton, Deborah; Roberts, Jane E.

    2016-01-01

    The present study examines verbal working memory over time in boys with fragile X syndrome (FXS) compared to nonverbal mental-age (NVMA) matched, typically developing (TD) boys. Concomitantly, the relationship between cortisol—a physiological marker for stress—and verbal working memory performance over time is examined to understand the role of physiological mechanisms in cognitive development in FXS. Participants were assessed between one and three times over a 2-year time frame using two verbal working memory tests that differ in complexity: memory for words and auditory working memory with salivary cortisol collected at the beginning and end of each assessment. Multilevel modeling results indicate specific deficits over time on the memory for words task in boys with FXS compared to TD controls that is exacerbated by elevated baseline cortisol. Similar increasing rates of growth over time were observed for boys with FXS and TD controls on the more complex auditory working memory task, but only boys with FXS displayed an association of increased baseline cortisol and lower performance. This study highlights the benefit of investigations of how dynamic biological and cognitive factors interact and influence cognitive development over time. PMID:26760450

  5. Do Motives to Undertake Physical Activity Relate to Physical Activity in Adolescent Boys and Girls?

    Science.gov (United States)

    Kopcakova, Jaroslava; Veselska, Zuzana Dankulincova; Geckova, Andrea Madarasova; Kalman, Michal; van Dijk, Jitse P; Reijneveld, Sijmen A

    2015-07-08

    Low levels of physical activity (PA) during adolescence contribute to obesity and poor health outcomes in adolescence, and these associations endure into adulthood. The aim of this study was to assess the associations between motives for PA and the level of PA among adolescent boys and girls. We obtained data regarding motives for PA and frequency of PA in 2010 via the Health Behavior in School-aged Children cross-sectional study in the Czech and Slovak Republics (n = 9018, mean age = 13.6, 49% boys). Respondents answered questions about their motives for PA and the frequency of their PA. Motives for PA were assessed using 13 items, which were structured in four groups. We explored the association between the motives for PA and sufficient PA using univariate and multivariate logistic regression models adjusted for age, and separately for boys and girls. "Good child" motives and Achievement motives were significantly associated with sufficient PA among both boys and girls. Health motives were associated with sufficient PA only among boys, and Social motives were associated with sufficient PA only among girls. Motives for PA were associated with the level of PA, and this association was partially gender dependent. These gender differences should be considered in interventions focusing on enhancement of PA.

  6. Cycling peak power in obese and lean 6- to 8-year-old girls and boys.

    Science.gov (United States)

    Aucouturier, Julien; Lazaar, Nordine; Doré, Eric; Meyer, Martine; Ratel, Sebastien; Duché, Pascale

    2007-06-01

    The purpose of this study was to investigate the possible effect of the difference in percentage body fat (%BF) and fat-free mass (FFM) on cycling peak power (CPP) in 6- to 8-year-old obese and lean untrained girls and boys. Obese (35 girls, 35 boys) and lean (35 girls, 35 boys) children were measured for obesity, %BF, calculated from skinfold measurements. FFM was calculated as body mass (BM) minus body fat. A force-velocity test on a cycle ergometer was used to measure CPP. CPP was related to anthropometric variables using standard and allometric models. CPP in absolute terms was higher in obese children than in lean children irrespective of gender. BM-related CPP was significantly lower in obese children than in lean ones, whereas no effect of obesity appeared on FFM-related CPP. Velocity at CPP (Vopt) was significantly lower and force at CPP (Fopt) was significantly higher in girls than in boys. Muscle power production was unaffected by obesity in children. Low BM-related CPP could explain the difficulty of taking up physical activities that are body-mass related in obese children. Gender difference for Vopt and Fopt shows that girls and boys may have different maturation patterns affecting CPP.

  7. Modelling the existing Irish energy-system to identify future energy costs and the maximum wind penetration feasible

    International Nuclear Information System (INIS)

    Connolly, D.; Leahy, M.; Lund, H.; Mathiesen, B.V.

    2010-01-01

    In this study a model of the Irish energy-system was developed using EnergyPLAN based on the year 2007, which was then used for three investigations. The first compares the model results with actual values from 2007 to validate its accuracy. The second illustrates the exposure of the existing Irish energy-system to future energy costs by considering future fuel prices, CO 2 prices, and different interest rates. The final investigation identifies the maximum wind penetration feasible on the 2007 Irish energy-system from a technical and economic perspective, as wind is the most promising fluctuating renewable resource available in Ireland. It is concluded that the reference model simulates the Irish energy-system accurately, the annual fuel costs for Ireland's energy could increase by approximately 58% from 2007 to 2020 if a business-as-usual scenario is followed, and the optimum wind penetration for the existing Irish energy-system is approximately 30% from both a technical and economic perspective based on 2020 energy prices. Future studies will use the model developed in this study to show that higher wind penetrations can be achieved if the existing energy-system is modified correctly. Finally, these results are not only applicable to Ireland, but also represent the issues facing many other countries. (author)

  8. Disruption of TCA Cycle and Glutamate Metabolism Identified by Metabolomics in an In Vitro Model of Amyotrophic Lateral Sclerosis.

    Science.gov (United States)

    Veyrat-Durebex, Charlotte; Corcia, Philippe; Piver, Eric; Devos, David; Dangoumau, Audrey; Gouel, Flore; Vourc'h, Patrick; Emond, Patrick; Laumonnier, Frédéric; Nadal-Desbarats, Lydie; Gordon, Paul H; Andres, Christian R; Blasco, Hélène

    2016-12-01

    This study aims to develop a cellular metabolomics model that reproduces the pathophysiological conditions found in amyotrophic lateral sclerosis in order to improve knowledge of disease physiology. We used a co-culture model combining the motor neuron-like cell line NSC-34 and the astrocyte clone C8-D1A, with each over-expressing wild-type or G93C mutant human SOD1, to examine amyotrophic lateral sclerosis (ALS) physiology. We focused on the effects of mutant human SOD1 as well as oxidative stress induced by menadione on intracellular metabolism using a metabolomics approach through gas chromatography coupled with mass spectrometry (GC-MS) analysis. Preliminary non-supervised analysis by Principal Component Analysis (PCA) revealed that cell type, genetic environment, and time of culture influenced the metabolomics profiles. Supervised analysis using orthogonal partial least squares discriminant analysis (OPLS-DA) on data from intracellular metabolomics profiles of SOD1 G93C co-cultures produced metabolites involved in glutamate metabolism and the tricarboxylic acid cycle (TCA) cycle. This study revealed the feasibility of using a metabolomics approach in a cellular model of ALS. We identified potential disruption of the TCA cycle and glutamate metabolism under oxidative stress, which is consistent with prior research in the disease. Analysis of metabolic alterations in an in vitro model is a novel approach to investigation of disease physiology.

  9. Identifying the effects of parameter uncertainty on the reliability of modeling the stability of overhanging, multi-layered, river banks

    Science.gov (United States)

    Samadi, A.; Amiri-Tokaldany, E.; Davoudi, M. H.; Darby, S. E.

    2011-11-01

    Composite river banks consist of a basal layer of non-cohesive material overlain by a cohesive layer of fine-grained material. In such banks, fluvial erosion of the lower, non-cohesive, layer typically occurs at a much higher rate than erosion of the upper part of the bank. Consequently, such banks normally develop a cantilevered bank profile, with bank retreat of the upper part of the bank taking place predominantly by the failure of these cantilevers. To predict the undesirable impacts of this type of bank retreat, a number of bank stability models have been presented in the literature. These models typically express bank stability by defining a factor of safety as the ratio of resisting and driving forces acting on the incipient failure block. These forces are affected by a range of controlling factors that include such aspects as the overhanging block geometry, and the geotechnical properties of the bank materials. In this paper, we introduce a new bank stability relation (for shear-type cantilever failures) that considers the hydrological status of cantilevered riverbanks, while beam-type failures are analyzed using a previously proposed relation. We employ these stability models to evaluate the effects of parameter uncertainty on the reliability of riverbank stability modeling of overhanging banks. This is achieved by employing a simple model of overhanging failure with respect to shear and beam failure mechanisms in a series of sensitivity tests and Monte Carlo analyses to identify, for each model parameter, the range of values that induce significant changes in the simulated factor of safety. The results show that care is required in parameterising (i) the geometrical shape of the overhanging-block and (ii) the bank material cohesion and unit weight, as predictions of bank stability are sensitive to variations of these factors.

  10. Reports of child sexual abuse of boys and girls: Longitudinal trends over a 20-year period in Victoria, Australia.

    Science.gov (United States)

    Mathews, Ben; Bromfield, Leah; Walsh, Kerryann; Cheng, Qinglu; Norman, Rosana E

    2017-04-01

    Although prevalence studies show girls are more frequently sexually abused than boys, a significant proportion of boys also experience child sexual abuse (CSA). The challenges for public policy are amplified for boys due to less developed public and professional sensitisation to boys' experiences, conceptions of masculinity, and less research on boys including into reporting trends and outcomes. We conducted a 20-year longitudinal time-trend analysis of government data to identify reporting trends and report outcomes for CSA in Victoria, Australia from 1993 to 2012. We stratified by child gender and reporter status. Results indicate a new sensitisation to CSA, especially for boys, although this trend was not stable. Marked change occurred in the last five years, likely influenced by major social and political events. Comparison over time revealed that from 1993 to 2012, the rate of reporting of boys increased 2.6-fold whereas there was a 1.5-fold increase for girls. Comparing genders, with regards to rate of reporting, in 1993, the sex ratio of girls to boys was 2:1, while by 2012 this ratio changed to 1.14:1. Reports by police and other mandated reporters accounted for the majority of the increase in reports over the 20-year period, suggesting unequal sensitisation. Positive report outcomes (i.e. substantiations, findings of harm, and referral to services) increased twelve-fold for boys, and nearly five-fold for girls, indicating the increased levels of reports were based in actual clinical need. Most of this increase occurred from 2009 to 2012, influenced by a compound of social, political and agency-related factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Prospective validation of a predictive model that identifies homeless people at risk of re-presentation to the emergency department.

    Science.gov (United States)

    Moore, Gaye; Hepworth, Graham; Weiland, Tracey; Manias, Elizabeth; Gerdtz, Marie Frances; Kelaher, Margaret; Dunt, David

    2012-02-01

    To prospectively evaluate the accuracy of a predictive model to identify homeless people at risk of representation to an emergency department. A prospective cohort analysis utilised one month of data from a Principal Referral Hospital in Melbourne, Australia. All visits involving people classified as homeless were included, excluding those who died. Homelessness was defined as living on the streets, in crisis accommodation, in boarding houses or residing in unstable housing. Rates of re-presentation, defined as the total number of visits to the same emergency department within 28 days of discharge from hospital, were measured. Performance of the risk screening tool was assessed by calculating sensitivity, specificity, positive and negative predictive values and likelihood ratios. Over the study period (April 1, 2009 to April 30, 2009), 3298 presentations from 2888 individuals were recorded. The homeless population accounted for 10% (n=327) of all visits and 7% (n=211) of all patients. A total of 90 (43%) homeless people re-presented to the emergency department. The predictive model included nine variables and achieved 98% (CI, 0.92-0.99) sensitivity and 66% (CI, 0.57-0.74) specificity. The positive predictive value was 68% and the negative predictive value was 98%. The positive likelihood ratio 2.9 (CI, 2.2-3.7) and the negative likelihood ratio was 0.03 (CI, 0.01-0.13). The high emergency department re-presentation rate for people who were homeless identifies unresolved psychosocial health needs. The emergency department remains a vital access point for homeless people, particularly after hours. The risk screening tool is key to identify medical and social aspects of a homeless patient's presentation to assist early identification and referral. Copyright © 2012 College of Emergency Nursing Australasia Ltd. Published by Elsevier Ltd. All rights reserved.

  12. Identifying Generalizable Image Segmentation Parameters for Urban Land Cover Mapping through Meta-Analysis and Regression Tree Modeling

    Directory of Open Access Journals (Sweden)

    Brian A. Johnson

    2018-01-01

    Full Text Available The advent of very high resolution (VHR satellite imagery and the development of Geographic Object-Based Image Analysis (GEOBIA have led to many new opportunities for fine-scale land cover mapping, especially in urban areas. Image segmentation is an important step in the GEOBIA framework, so great time/effort is often spent to ensure that computer-generated image segments closely match real-world objects of interest. In the remote sensing community, segmentation is frequently performed using the multiresolution segmentation (MRS algorithm, which is tuned through three user-defined parameters (the scale, shape/color, and compactness/smoothness parameters. The scale parameter (SP is the most important parameter and governs the average size of generated image segments. Existing automatic methods to determine suitable SPs for segmentation are scene-specific and often computationally intensive, so an approach to estimating appropriate SPs that is generalizable (i.e., not scene-specific could speed up the GEOBIA workflow considerably. In this study, we attempted to identify generalizable SPs for five common urban land cover types (buildings, vegetation, roads, bare soil, and water through meta-analysis and nonlinear regression tree (RT modeling. First, we performed a literature search of recent studies that employed GEOBIA for urban land cover mapping and extracted the MRS parameters used, the image properties (i.e., spatial and radiometric resolutions, and the land cover classes mapped. Using this data extracted from the literature, we constructed RT models for each land cover class to predict suitable SP values based on the: image spatial resolution, image radiometric resolution, shape/color parameter, and compactness/smoothness parameter. Based on a visual and quantitative analysis of results, we found that for all land cover classes except water, relatively accurate SPs could be identified using our RT modeling results. The main advantage of our

  13. Taste perception and sensory sensitivity: Relationship to feeding problems in boys with Barth Syndrome.

    Science.gov (United States)

    Reynolds, Stacey; Kreider, Consuelo M; Meeley, Lauren E; Bendixen, Roxanna M

    2015-03-01

    Feeding problems are common in boys with Barth syndrome and may contribute to the population's propensity for growth delay and muscle weakness. The purpose of this study was to quantify and describe these feeding issues and examine altered taste perception and sensory sensitivity as contributing factors. A cross-sectional, two-group comparison design was used to examine feeding preferences and behaviors, chemical taste perception, and sensory sensitivities in fifty boys with (n=24) and without (n=26) Barth ages 4-17 years. Taste perception was measured using chemical test strips saturated with phenylthiocarbamide (PTC) and sodium benzoate (NaB). Feeding problems were documented by parents using a Food Inventory, while sensory sensitivities were recorded using a Short Sensory Profile. Boys with Barth differed significantly from typical peers with regards to problem feeding behaviors. For boys with Barth, food refusal and food selectivity were identified as being present in 50% the sample, while 70% of had identified problems related to gagging or swallowing foods. About half of all Barth families noted that their child's eating habits did not match the family's and that separate meals were often prepared. As demonstrated in previous research, about 50% of boys with Barth demonstrated probable or definite differences in taste/smell sensitivity, which was significantly higher than controls. On tests of chemical taste perception, boys with Barth were significantly more likely to be supertasters to PTC and non-tasters to NaB. Taster-status did not directly relate to the presence of feeding problems, however, taste/smell sensitivity did significantly relate to food selectivity by type and texture. Results indicate feeding problems in at least 50-70% of boys with Barth syndrome, and suggest that behaviors are often present before 6 months of age. Differences in taste perception may influence dietary choices in boys with Barth, particularly their craving of salty foods

  14. HPV vaccination acceptability in young boys

    Directory of Open Access Journals (Sweden)

    Giancarlo Tisi

    2013-09-01

    Full Text Available PURPOSE: The aim of this study was to evaluate the comprehension and acceptance of HPV vaccination in parents of adolescent boys aged 11 to 15 years. METHODS: A cross-sectional survey was conducted by means of questionnaires sent directly to the homes of all families with young males aged between 11 and 15, residents of three municipalities of the Province of Brescia, Italy. The documentation also contained an informative leaflet summarizing the HPV-related disease characteristics, the burden of disease and the available strategies for prevention and treatment, illustrating the rationale of vaccination and describing the project and its phases. The questionnaire included questions on demographic data, acceptance and motivations for HPV vaccination. The collected data was analyzed using descriptive statistics. At the end of the study, parents who received the questionnaires were also offered the possibility of vaccinating their male sons for free. RESULTS: From a total of 1072 questionnaires sent, 161 where returned from the three selected municipalities (average response rate 15%; 97% of adolescent males involved in the study were Italian and 91% Catholic; 97% of parents declared themselves to be willing to vaccinate their sons: the principal motivation given (92% was prevention of the disease, cancerous or not, related to viral infection. Among the respondents not willing to vaccinate their sons, the motivation was lack of information about the vaccine and the disease. At the end of the study, around 71 boys were vaccinated. DISCUSSION: To our knowledge, this is the first survey in Italy exclusively conducted on parents of adolescent males about the acceptability and feasibility of vaccination against HPV: a very high percentage of respondents was favorable to accept the vaccination for their sons, the main motivation being the fact that parents considered protecting their sons from HPV-related diseases highly important. Of the 161 boys

  15. Why Are Girls Less Physically Active than Boys? Findings from the LOOK Longitudinal Study.

    Directory of Open Access Journals (Sweden)

    Rohan M Telford

    Full Text Available A gender-based disparity in physical activity (PA among youth, whereby girls are less active than boys is a persistent finding in the literature. A greater understanding of the mechanisms underlying this difference has potential to guide PA intervention strategies.Data were collected at age 8 and 12 years (276 boys, 279 girls from 29 schools as part of the LOOK study. Multilevel linear models were fitted separately for boys and girls to examine effects of individual, family and environmental level correlates on pedometer measured PA. Cardio-respiratory fitness (multi-stage run, percent fat (DEXA, eye-hand coordination (throw and catch test and perceived competence in physical education (questionnaire were used as individual level correlates. At the family level, parent's support and education (questionnaire were used. School attended and extracurricular sport participation were included as environmental level correlates.Girls were 19% less active than boys (9420 vs 11360 steps/day, p<0.001, 95%CI [1844, 2626]. Lower PA among girls was associated with weaker influences at the school and family levels and through lower participation in extracurricular sport. School attended explained some of the variation in boys PA (8.4% but not girls. Girls compared to boys had less favourable individual attributes associated with PA at age 8 years, including 18% lower cardio-respiratory fitness (3.5 vs 4.2, p<0.001, CI [0.5,0.9], 44% lower eye-hand coordination (11.0 vs 17.3, p<0.001, CI [5.1,9.0], higher percent body fat (28% vs 23%, p<0.001, CI [3.5,5.7] and 9% lower perceived competence in physical education (7.7 vs 8.4, p<0.001, CI [0.2,0.9]. Participation in extracurricular sport at either age 8 or 12 years was protective against declines in PA over time among boys but not girls.Girls PA was less favourably influenced by socio-ecological factors at the individual, family, school and environmental levels. These factors are potentially modifiable suggesting

  16. Identifying the preferred subset of enzymatic profiles in nonlinear kinetic metabolic models via multiobjective global optimization and Pareto filters.

    Directory of Open Access Journals (Sweden)

    Carlos Pozo

    Full Text Available Optimization models in metabolic engineering and systems biology focus typically on optimizing a unique criterion, usually the synthesis rate of a metabolite of interest or the rate of growth. Connectivity and non-linear regulatory effects, however, make it necessary to consider multiple objectives in order to identify useful strategies that balance out different metabolic issues. This is a fundamental aspect, as optimization of maximum yield in a given condition may involve unrealistic values in other key processes. Due to the difficulties associated with detailed non-linear models, analysis using stoichiometric descriptions and linear optimization methods have become rather popular in systems biology. However, despite being useful, these approaches fail in capturing the intrinsic nonlinear nature of the underlying metabolic systems and the regulatory signals involved. Targeting more complex biological systems requires the application of global optimization methods to non-linear representations. In this work we address the multi-objective global optimization of metabolic networks that are described by a special class of models based on the power-law formalism: the generalized mass action (GMA representation. Our goal is to develop global optimization methods capable of efficiently dealing with several biological criteria simultaneously. In order to overcome the numerical difficulties of dealing with multiple criteria in the optimization, we propose a heuristic approach based on the epsilon constraint method that reduces the computational burden of generating a set of Pareto optimal alternatives, each achieving a unique combination of objectives values. To facilitate the post-optimal analysis of these solutions and narrow down their number prior to being tested in the laboratory, we explore the use of Pareto filters that identify the preferred subset of enzymatic profiles. We demonstrate the usefulness of our approach by means of a case study

  17. Identifying the preferred subset of enzymatic profiles in nonlinear kinetic metabolic models via multiobjective global optimization and Pareto filters.

    Science.gov (United States)

    Pozo, Carlos; Guillén-Gosálbez, Gonzalo; Sorribas, Albert; Jiménez, Laureano

    2012-01-01

    Optimization models in metabolic engineering and systems biology focus typically on optimizing a unique criterion, usually the synthesis rate of a metabolite of interest or the rate of growth. Connectivity and non-linear regulatory effects, however, make it necessary to consider multiple objectives in order to identify useful strategies that balance out different metabolic issues. This is a fundamental aspect, as optimization of maximum yield in a given condition may involve unrealistic values in other key processes. Due to the difficulties associated with detailed non-linear models, analysis using stoichiometric descriptions and linear optimization methods have become rather popular in systems biology. However, despite being useful, these approaches fail in capturing the intrinsic nonlinear nature of the underlying metabolic systems and the regulatory signals involved. Targeting more complex biological systems requires the application of global optimization methods to non-linear representations. In this work we address the multi-objective global optimization of metabolic networks that are described by a special class of models based on the power-law formalism: the generalized mass action (GMA) representation. Our goal is to develop global optimization methods capable of efficiently dealing with several biological criteria simultaneously. In order to overcome the numerical difficulties of dealing with multiple criteria in the optimization, we propose a heuristic approach based on the epsilon constraint method that reduces the computational burden of generating a set of Pareto optimal alternatives, each achieving a unique combination of objectives values. To facilitate the post-optimal analysis of these solutions and narrow down their number prior to being tested in the laboratory, we explore the use of Pareto filters that identify the preferred subset of enzymatic profiles. We demonstrate the usefulness of our approach by means of a case study that optimizes the

  18. Evaluating Boy Scout Geology Education, A Pilot Study

    Science.gov (United States)

    Hintz, R. S.; Thomson, B.

    2008-12-01

    This study investigated geology knowledge acquisition by Boy Scouts through use of the Boy Scout Geology Merit Handbook. In this study, boys engaged in hands-on interactive learning following the requirements set forth in the Geology Merit Badge Handbook. The purposes of this study were to determine the amount of geology content knowledge engendered in adolescent males through the use of the Geology Merit Badge Handbook published by the Boy Scouts of America; to determine if single sex, activity oriented, free-choice learning programs can be effective in promoting knowledge development in young males; and to determine if boys participating in the Scouting program believed their participation helped them succeed in school. Members of a local Boy Scout Troop between the ages of 11 and 18 were invited to participate in a Geology Merit Badge program. Boys who did not already possess the badge were allowed to self-select participation. The boys' content knowledge of geology, rocks, and minerals was pre- and post-tested. Boys were interviewed about their school and Scouting experiences; whether they believed their Scouting experiences and work in Merit Badges contributed to their success in school. Contributing educational theories included single-sex education, informal education with free-choice learning, learning styles, hands-on activities, and the social cognitive theory concept of self-efficacy. Boys who completed this study seemed to possess a greater knowledge of geology than they obtained in school. If boys who complete the Boy Scout Geology Merit Badge receive additional geological training, their field experiences and knowledge acquired through this learning experience will be beneficial, and a basis for continued scaffolding of geologic knowledge.

  19. Bone Density in Peripubertal Boys with Autism Spectrum Disorders

    Science.gov (United States)

    Neumeyer, Ann M.; Gates, Amy; Ferrone, Christine; Lee, Hang; Misra, Madhusmita

    2013-01-01

    We determined whether bone mineral density (BMD) is lower in boys with autism spectrum disorders (ASD) than controls, and also assessed variables that may affect BMD in ASD. BMD was measured using dual energy X-ray absorptiometry (DXA) in 18 boys with ASD and 19 controls 8-14 years old. Boys with ASD had lower BMD Z-scores at the spine, hip and…

  20. Aspirations, Progress and Perceptions of Boys from a Single Sex School Following the Changeover to Coeducation

    Science.gov (United States)

    Yates, Shirley M.

    2004-01-01

    Career and further education aspirations, educational progress and perceptions of the learning environment were measured annually over three years in primary and secondary boys from a single sex non-government school, following the changeover to coeducation. Hierarchical Linear Modelling analyses revealed the significant role played by the career…