Validation of the Social Appearance Anxiety Scale: factor, convergent, and divergent validity.
Levinson, Cheri A; Rodebaugh, Thomas L
2011-09-01
The Social Appearance Anxiety Scale (SAAS) was created to assess fear of overall appearance evaluation. Initial psychometric work indicated that the measure had a single-factor structure and exhibited excellent internal consistency, test-retest reliability, and convergent validity. In the current study, the authors further examined the factor, convergent, and divergent validity of the SAAS in two samples of undergraduates. In Study 1 (N = 323), the authors tested the factor structure, convergent, and divergent validity of the SAAS with measures of the Big Five personality traits, negative affect, fear of negative evaluation, and social interaction anxiety. In Study 2 (N = 118), participants completed a body evaluation that included measurements of height, weight, and body fat content. The SAAS exhibited excellent convergent and divergent validity with self-report measures (i.e., self-esteem, trait anxiety, ethnic identity, and sympathy), predicted state anxiety experienced during the body evaluation, and predicted body fat content. In both studies, results confirmed a single-factor structure as the best fit to the data. These results lend additional support for the use of the SAAS as a valid measure of social appearance anxiety.
ERIC Educational Resources Information Center
Cleary, Timothy J.; Dembitzer, Leah; Kettler, Ryan J.
2015-01-01
Using a sample of 348 middle school students, we gathered evidence regarding the internal consistency of scores, as well as the internal factor structure and convergent validity evidence for inferences from a self-report questionnaire called the Self-Regulation Strategy Inventory-Self Report. Confirmatory factor analysis revealed that the fit…
Validation of the Social Appearance Anxiety Scale: Factor, Convergent, and Divergent Validity
ERIC Educational Resources Information Center
Levinson, Cheri A.; Rodebaugh, Thomas L.
2011-01-01
The Social Appearance Anxiety Scale (SAAS) was created to assess fear of overall appearance evaluation. Initial psychometric work indicated that the measure had a single-factor structure and exhibited excellent internal consistency, test-retest reliability, and convergent validity. In the current study, the authors further examined the factor,…
Piker, Erin G; Kaylie, David M; Garrison, Douglas; Tucci, Debara L
2015-01-01
Psychiatric comorbidities, particularly anxiety-related pathologies, are often observed in dizzy patients. The Hospital Anxiety and Depression Scale (HADS) is a widely used self-report instrument used to screen for anxiety and depression in medical outpatient settings. The purpose of this study was to assess the factor structure, internal consistency and convergent validity of the HADS in an unselected group of patients with dizziness. The HADS and the Dizziness Handicap Inventory (DHI) were administered to 205 dizzy patients. An exploratory factor analysis was conducted and indicated a 3-factor structure, inconsistent with the 2-subscale structure (i.e. anxiety and depression) of the HADS. The total scale was found to be internally consistent, and convergent validity, as assessed using the DHI, was acceptable. Overall findings suggest that the HADS should not be used as a tool for psychiatric differential diagnosis, but rather as a helpful screener for general psychiatric distress in the two domains of psychiatric illness most germane in dizzy patients. © 2015 S. Karger AG, Basel.
Le, Minh Thi Hong; Tran, Thach Duc; Holton, Sara; Nguyen, Huong Thanh; Wolfe, Rory; Fisher, Jane
2017-01-01
To assess the internal consistency, latent structure and convergent validity of the Depression, Anxiety and Stress Scale-21 (DASS-21) among adolescents in Vietnam. An anonymous, self-completed questionnaire was conducted among 1,745 high school students in Hanoi, Vietnam between October, 2013 and January, 2014. Confirmatory factor analyses were performed to assess the latent structure of the DASS-21. Factorial invariance between girls and boys was examined. Cronbach alphas and correlation coefficients between DASS-21 factor scores and the domain scores of the Duke Health Profile Adolescent Vietnamese validated version (ADHP-V) were calculated to assess DASS-21 internal consistency and convergent validity. A total of 1,606/ 1,745 (92.6%) students returned the questionnaire. Of those, 1,387 students provided complete DASS-21 data. The scale demonstrated adequate internal consistency (Cronbach α: 0.761 to 0.906). A four-factor model showed the best fit to the data. Items loaded significantly on a common general distress factor, the depression, and the anxiety factors, but few on the stress factor (p<0.05). DASS-21 convergent validity was confirmed with moderate correlation coefficients (-0.47 to -0.66) between its factor scores and the ADHP-V mental health related domains. The DASS-21 is reliable and suitable for use to assess symptoms of common mental health problems, especially depression and anxiety among Vietnamese adolescents. However, its ability in detecting stress among these adolescents may be limited. Further research is warrant to explore these results.
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Mazer, Joseph P.
2017-01-01
The results of this study compile convergent validity evidence for the Student Interest Scale and Student Engagement Scale through associations among emotional support, emotion work, student interest, and engagement. Confirmatory factor analysis indicates that the factor structures of the measures are stable, reliable, and valid. The results…
Tran, Thach Duc; Holton, Sara; Nguyen, Huong Thanh; Wolfe, Rory; Fisher, Jane
2017-01-01
Objectives To assess the internal consistency, latent structure and convergent validity of the Depression, Anxiety and Stress Scale-21 (DASS-21) among adolescents in Vietnam. Method An anonymous, self-completed questionnaire was conducted among 1,745 high school students in Hanoi, Vietnam between October, 2013 and January, 2014. Confirmatory factor analyses were performed to assess the latent structure of the DASS-21. Factorial invariance between girls and boys was examined. Cronbach alphas and correlation coefficients between DASS-21 factor scores and the domain scores of the Duke Health Profile Adolescent Vietnamese validated version (ADHP-V) were calculated to assess DASS-21 internal consistency and convergent validity. Results A total of 1,606/ 1,745 (92.6%) students returned the questionnaire. Of those, 1,387 students provided complete DASS-21 data. The scale demonstrated adequate internal consistency (Cronbach α: 0.761 to 0.906). A four-factor model showed the best fit to the data. Items loaded significantly on a common general distress factor, the depression, and the anxiety factors, but few on the stress factor (p<0.05). DASS-21 convergent validity was confirmed with moderate correlation coefficients (-0.47 to -0.66) between its factor scores and the ADHP-V mental health related domains. Conclusions The DASS-21 is reliable and suitable for use to assess symptoms of common mental health problems, especially depression and anxiety among Vietnamese adolescents. However, its ability in detecting stress among these adolescents may be limited. Further research is warrant to explore these results. PMID:28723909
Bastiaens, Tim; Claes, Laurence; Smits, Dirk; De Clercq, Barbara; De Fruyt, Filip; Rossi, Gina; Vanwalleghem, Dominique; Vermote, Rudi; Lowyck, Benedicte; Claes, Stephan; De Hert, Marc
2016-02-01
The factor structure and the convergent validity of the Personality Inventory for DSM-5 (PID-5), a self-report questionnaire designed to measure personality pathology as advocated in the fifth edition, Section III of Diagnostic and Statistical Manual of Mental Disorders (DSM-5), are already demonstrated in general population samples, but need replication in clinical samples. In 240 Flemish inpatients, we examined the factor structure of the PID-5 by means of exploratory structural equation modeling. Additionally, we investigated differences in PID-5 higher order domain scores according to gender, age and educational level, and explored convergent and discriminant validity by relating the PID-5 with the Dimensional Assessment of Personality Pathology-Basic Questionnaire and by comparing PID-5 scores of inpatients with and without a DSM-IV categorical personality disorder diagnosis. Our results confirmed the original five-factor structure of the PID-5. The reliability and the convergent and discriminant validity of the PID-5 proved to be adequate. Implications for future research are discussed. © The Author(s) 2015.
Factor structure and construct validity of the Anxiety Sensitivity Index among island Puerto Ricans.
Cintrón, Jennifer A; Carter, Michele M; Suchday, Sonia; Sbrocco, Tracy; Gray, James
2005-01-01
The factor structure and convergent and discriminant validity of the Anxiety Sensitivity Index (ASI) were examined among a sample of 275 island Puerto Ricans. Results from a confirmatory factor analysis (CFA) comparing our data to factor solutions commonly reported as representative of European American and Spanish populations indicated a poor fit. A subsequent exploratory factor analysis (EFA) indicated that a two-factor solution (Factor 1, Anxiety Sensitivity; Factor 2, Emotional Concerns) provided the best fit. Correlations between the ASI and anxiety measures were moderately high providing evidence of convergent validity, while correlations between the ASI and BDI were significantly lower providing evidence of discriminant validity. Scores on all measures were positively correlated with acculturation, suggesting that those who ascribe to more traditional Hispanic culture report elevated anxiety.
Psychometric evaluation of the Swedish version of Rosenberg's self-esteem scale.
Eklund, Mona; Bäckström, Martin; Hansson, Lars
2018-04-01
The widely used Rosenberg's self-esteem scale (RSES) has not been evaluated for psychometric properties in Sweden. This study aimed at analyzing its factor structure, internal consistency, criterion, convergent and discriminant validity, sensitivity to change, and whether a four-graded Likert-type response scale increased its reliability and validity compared to a yes/no response scale. People with mental illness participating in intervention studies to (1) promote everyday life balance (N = 223) or (2) remedy self-stigma (N = 103) were included. Both samples completed the RSES and questionnaires addressing quality of life and sociodemographic data. Sample 1 also completed instruments chosen to assess convergent and discriminant validity: self-mastery (convergent validity), level of functioning and occupational engagement (discriminant validity). Confirmatory factor analysis (CFA), structural equation modeling, and conventional inferential statistics were used. Based on both samples, the Swedish RSES formed one factor and exhibited high internal consistency (>0.90). The two response scales were equivalent. Criterion validity in relation to quality of life was demonstrated. RSES could distinguish between women and men (women scoring lower) and between diagnostic groups (people with depression scoring lower). Correlations >0.5 with variables chosen to reflect convergent validity and around 0.2 with variables used to address discriminant validity further highlighted the construct validity of RSES. The instrument also showed sensitivity to change. The Swedish RSES exhibited a one-component factor structure and showed good psychometric properties in terms of good internal consistency, criterion, convergent and discriminant validity, and sensitivity to change. The yes/no and the four-graded Likert-type response scales worked equivalently.
Swineford, Lauren B; Guthrie, Whitney; Thurm, Audrey
2015-12-01
The purpose of this study was to report on the construct, convergent, and divergent validity of the Mullen Scales of Early Learning (MSEL), a widely used test of development for young children. The sample consisted of 399 children with a mean age of 3.38 years (SD = 1.14) divided into a group of children with autism spectrum disorder (ASD) and a group of children not on the autism spectrum, with and without developmental delays. The study used the MSEL and several other measures assessing constructs relevant to the age range--including developmental skills, autism symptoms, and psychopathology symptoms--across multiple methods of assessment. Multiple-group confirmatory factor analyses revealed good overall fit and equal form of the MSEL 1-factor model across the ASD and nonspectrum groups, supporting the construct validity of the MSEL. However, neither full nor partial invariance of factor loadings was established because of the lower loadings in the ASD group compared with the nonspectrum group. Exploratory structural equation modeling revealed that other measures of developmental skills loaded together with the MSEL domain scores on a Developmental Functioning factor, supporting convergent validity of the MSEL. Divergent validity was supported by the lack of loading of MSEL domain scores on Autism Symptoms or Emotion/Behavior Problems factors. Although factor structure and loadings varied across groups, convergent and divergent validity findings were similar in the ASD and nonspectrum samples. Together, these results demonstrate evidence for the construct, convergent, and divergent validity of the MSEL using powerful data-analytic techniques. (c) 2015 APA, all rights reserved).
Ethnicity and Anxiety: A Psychometric Evaluation of the STICSA
ERIC Educational Resources Information Center
Lancaster, Steven L.; Melka, Stephen E.; Klein, Keith P.; Rodriguez, Benjamin F.
2015-01-01
The current study examined the convergent validity and factor structure of the State-Trait Inventory of Cognitive and Somatic Anxiety in a sample of African Americans and European Americans. Validity analyses revealed similar associations; however, the factor analysis failed to support the original factor structure and factorial variance was…
Continuous analogues of matrix factorizations
Townsend, Alex; Trefethen, Lloyd N.
2015-01-01
Analogues of singular value decomposition (SVD), QR, LU and Cholesky factorizations are presented for problems in which the usual discrete matrix is replaced by a ‘quasimatrix’, continuous in one dimension, or a ‘cmatrix’, continuous in both dimensions. Two challenges arise: the generalization of the notions of triangular structure and row and column pivoting to continuous variables (required in all cases except the SVD, and far from obvious), and the convergence of the infinite series that define the cmatrix factorizations. Our generalizations of triangularity and pivoting are based on a new notion of a ‘triangular quasimatrix’. Concerning convergence of the series, we prove theorems asserting convergence provided the functions involved are sufficiently smooth. PMID:25568618
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Andrei, Federica; Smith, Martin M.; Surcinelli, Paola; Baldaro, Bruno; Saklofske, Donald H.
2016-01-01
This study investigated the structure and validity of the Italian translation of the Trait Emotional Intelligence Questionnaire. Data were self-reported from 227 participants. Confirmatory factor analysis supported the four-factor structure of the scale. Hierarchical regressions also demonstrated its incremental validity beyond demographics, the…
Eadeh, Hana-May; Langberg, Joshua M; Molitor, Stephen J; Behrhorst, Katie; Smith, Zoe R; Evans, Steven W
2018-02-01
Parenting stress is common in families with an adolescent with attention-deficit/hyperactivity disorder (ADHD). The Stress Index for Parents of Adolescents (SIPA) was developed to assess parenting stress but has not been validated outside of the original development work. This study examined the factor structure and sources of convergent validity of the SIPA in a sample of adolescents diagnosed with ADHD ( M age = 12.3, N = 327) and their caregivers. Three first-order models, two bifactor models, and one higher order model were evaluated; none met overall model fit criteria but the first-order nine-factor model displayed the best fit. Convergent validity was also assessed and the SIPA adolescent domain was moderately correlated with measures of family impairment and conflict after accounting for ADHD symptom severity. Implications of these findings for use of the SIPA in ADHD samples are discussed along with directions for future research focused on parent stress and ADHD.
The Structure of Intellect, Its Interpretations and Uses.
ERIC Educational Resources Information Center
Meeker, Mary Nacol
Using Guilford's model, the text reviews the structure of the intellect (SOI) and its operations, contents, and products. Those operations and components are further described, including the factors of cognition, memory, evaluation, convergent-production, and divergent-production. For each factor, the figural, symbolic, and semantic dimensions are…
Sharif Nia, Hamid; Pahlevan Sharif, Saeed; Boyle, Christopher; Yaghoobzadeh, Ameneh; Tahmasbi, Bahram; Rassool, G Hussein; Taebei, Mozhgan; Soleimani, Mohammad Ali
2018-04-01
This study aimed to determine the factor structure of the spiritual well-being among a sample of the Iranian veterans. In this methodological research, 211 male veterans of Iran-Iraq warfare completed the Paloutzian and Ellison spiritual well-being scale. Maximum likelihood (ML) with oblique rotation was used to assess domain structure of the spiritual well-being. The construct validity of the scale was assessed using confirmatory factor analysis (CFA), convergent validity, and discriminant validity. Reliability was evaluated with Cronbach's alpha, Theta (θ), and McDonald Omega (Ω) coefficients, intra-class correlation coefficient (ICC), and construct reliability (CR). Results of ML and CFA suggested three factors which were labeled "relationship with God," "belief in fate and destiny," and "life optimism." The ICC, coefficients of the internal consistency, and CR were >.7 for the factors of the scale. Convergent validity and discriminant validity did not fulfill the requirements. The Persian version of spiritual well-being scale demonstrated suitable validity and reliability among the veterans of Iran-Iraq warfare.
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VanVoorhis, Carmen R. Wilson; Blumentritt, Tracie L.
2007-01-01
We examined the internal consistency reliability, convergent and divergent validity, and factor structure of the Beck Depression Inventory-II (BDI-II) in a sample of 131 Mexican American youth. The BDI-II demonstrated excellent internal consistency reliability (alpha = 0.90) and solid convergent and divergent validity with various clinical scales…
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Marsh, Herbert W.; Abduljabbar, Adel Salah; Abu-Hilal, Maher M.; Morin, Alexandre J. S.; Abdelfattah, Faisal; Leung, Kim Chau; Xu, Man K.; Nagengast, Benjamin; Parker, Philip
2013-01-01
For the international Trends in International Mathematics and Science Study (TIMSS2007) math and science motivation scales (self-concept, positive affect, and value), we evaluated the psychometric properties (factor structure, method effects, gender differences, and convergent and discriminant validity) in 4 Arab-speaking countries (Saudi Arabia,…
Delgado, Beatriz; García-Fernández, José M; Martínez-Monteagudo, María C; Inglés, Cándido J; Marzo, Juan C; La Greca, Annette M; Hugon, Mandarine
2018-06-02
School and social anxiety are common problems and have a significant impact on youths' development. Nevertheless, the questionnaires to assess these anxious symptoms in French adolescents have limitations. The aim of this study is to provide a French version of the Social Anxiety Scale for Adolescents (SAS-A) and the School Anxiety Inventory (SAI), analysing their psychometric properties by the factor structure, internal consistency, and convergent validity. The SAS-A and the SAI were collectively administered in a sample of 1011 French adolescents (48.5% boys) ranging in age from 11 to 18 years. Confirmatory factor analyses replicated the previously identified correlated three-factor structure of the SAS-A and the correlated four-factor structure of the SAI. Acceptable internal consistency indexes were found for SAS-A and SAI scores. Correlations supported the convergent validity of the questionnaires' subscales. Overall, results supported the internal consistency and validity of the French versions of the SAS-A and SAI.
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He, Jian-Ping; Burstein, Marcy; Schmitz, Anja; Merikangas, Kathleen R.
2013-01-01
The Strengths and Difficulties Questionnaire (SDQ) is one of the most commonly used instruments for screening psychopathology in children and adolescents. This study evaluated the hypothesized five-factor structure of the SDQ and examined its convergent validity against comprehensive clinical diagnostic assessments. Data were derived from the…
Young Children's Psychological Selves: Convergence with Maternal Reports of Child Personality
ERIC Educational Resources Information Center
Brown, Geoffrey L.; Mangelsdorf, Sarah C.; Agathen, Jean M.; Ho, Moon-Ho
2008-01-01
The present research examined five-year-old children's psychological self-concepts. Non-linear factor analysis was used to model the latent structure of the children's self-view questionnaire (CSVQ; Eder, 1990), a measure of children's self-concepts. The coherence and reliability of the emerging factor structure indicated that young children are…
NASA Astrophysics Data System (ADS)
Fan, Xiao-Ning; Zhi, Bo
2017-07-01
Uncertainties in parameters such as materials, loading, and geometry are inevitable in designing metallic structures for cranes. When considering these uncertainty factors, reliability-based design optimization (RBDO) offers a more reasonable design approach. However, existing RBDO methods for crane metallic structures are prone to low convergence speed and high computational cost. A unilevel RBDO method, combining a discrete imperialist competitive algorithm with an inverse reliability strategy based on the performance measure approach, is developed. Application of the imperialist competitive algorithm at the optimization level significantly improves the convergence speed of this RBDO method. At the reliability analysis level, the inverse reliability strategy is used to determine the feasibility of each probabilistic constraint at each design point by calculating its α-percentile performance, thereby avoiding convergence failure, calculation error, and disproportionate computational effort encountered using conventional moment and simulation methods. Application of the RBDO method to an actual crane structure shows that the developed RBDO realizes a design with the best tradeoff between economy and safety together with about one-third of the convergence speed and the computational cost of the existing method. This paper provides a scientific and effective design approach for the design of metallic structures of cranes.
A Second-Order Confirmatory Factor Analysis of the Moral Distress Scale-Revised for Nurses.
Sharif Nia, Hamid; Shafipour, Vida; Allen, Kelly-Ann; Heidari, Mohammad Reza; Yazdani-Charati, Jamshid; Zareiyan, Armin
2017-01-01
Moral distress is a growing problem for healthcare professionals that may lead to dissatisfaction, resignation, or occupational burnout if left unattended, and nurses experience different levels of this phenomenon. This study aims to investigate the factor structure of the Persian version of the Moral Distress Scale-Revised in intensive care and general nurses. This methodological research was conducted with 771 nurses from eight hospitals in the Mazandaran Province of Iran in 2017. Participants completed the Moral Distress Scale-Revised, data collected, and factor structure assessed using the construct, convergent, and divergent validity methods. The reliability of the scale was assessed using internal consistency (Cronbach's alpha, Theta, and McDonald's omega coefficients) and construct reliability. Ethical considerations: This study was approved by the Ethics Committee of Mazandaran University of Medical Sciences. The exploratory factor analysis ( N = 380) showed that the Moral Distress Scale-Revised has five factors: lack of professional competence at work, ignoring ethical issues and patient conditions, futile care, carrying out the physician's orders without question and unsafe care, and providing care under personal and organizational pressures, which explained 56.62% of the overall variance. The confirmatory factor analysis ( N = 391) supported the five-factor solution and the second-order latent factor model. The first-order model did not show a favorable convergent and divergent validity. Ultimately, the Moral Distress Scale-Revised was found to have a favorable internal consistency and construct reliability. The Moral Distress Scale-Revised was found to be a multidimensional construct. The data obtained confirmed the hypothesis of the factor structure model with a latent second-order variable. Since the convergent and divergent validity of the scale were not confirmed in this study, further assessment is necessary in future studies.
Yokoyama, Ken Daigoro; Pollock, David D
2012-01-01
Functional modification of regulatory proteins can affect hundreds of genes throughout the genome, and is therefore thought to be almost universally deleterious. This belief, however, has recently been challenged. A potential example comes from transcription factor SP1, for which statistical evidence indicates that motif preferences were altered in eutherian mammals. Here, we set out to discover possible structural and theoretical explanations, evaluate the role of selection in SP1 evolution, and discover effects on coregulatory proteins. We show that SP1 motif preferences were convergently altered in birds as well as mammals, inducing coevolutionary changes in over 800 regulatory regions. Structural and phylogenic evidence implicates a single causative amino acid replacement at the same SP1 position along both lineages. Furthermore, paralogs SP3 and SP4, which coregulate SP1 target genes through competitive binding to the same sites, have accumulated convergent replacements at the homologous position multiple times during eutherian and bird evolution, presumably to preserve competitive binding. To determine plausibility, we developed and implemented a simple model of transcription factor and binding site coevolution. This model predicts that, in contrast to prevailing beliefs, even small selective benefits per locus can drive concurrent fixation of transcription factor and binding site mutants under a broad range of conditions. Novel binding sites tend to arise de novo, rather than by mutation from ancestral sites, a prediction substantiated by SP1-binding site alignments. Thus, multiple lines of evidence indicate that selection has driven convergent evolution of transcription factors along with their binding sites and coregulatory proteins.
Yokoyama, Ken Daigoro; Pollock, David D.
2012-01-01
Functional modification of regulatory proteins can affect hundreds of genes throughout the genome, and is therefore thought to be almost universally deleterious. This belief, however, has recently been challenged. A potential example comes from transcription factor SP1, for which statistical evidence indicates that motif preferences were altered in eutherian mammals. Here, we set out to discover possible structural and theoretical explanations, evaluate the role of selection in SP1 evolution, and discover effects on coregulatory proteins. We show that SP1 motif preferences were convergently altered in birds as well as mammals, inducing coevolutionary changes in over 800 regulatory regions. Structural and phylogenic evidence implicates a single causative amino acid replacement at the same SP1 position along both lineages. Furthermore, paralogs SP3 and SP4, which coregulate SP1 target genes through competitive binding to the same sites, have accumulated convergent replacements at the homologous position multiple times during eutherian and bird evolution, presumably to preserve competitive binding. To determine plausibility, we developed and implemented a simple model of transcription factor and binding site coevolution. This model predicts that, in contrast to prevailing beliefs, even small selective benefits per locus can drive concurrent fixation of transcription factor and binding site mutants under a broad range of conditions. Novel binding sites tend to arise de novo, rather than by mutation from ancestral sites, a prediction substantiated by SP1-binding site alignments. Thus, multiple lines of evidence indicate that selection has driven convergent evolution of transcription factors along with their binding sites and coregulatory proteins. PMID:23019068
ERIC Educational Resources Information Center
Ansell, Emily B.; Pincus, Aaron L.
2004-01-01
Research investigating the structural convergence of the Interpersonal Circumplex (IPC; Wiggins, 1979, 1995) with the Five Factor Model (FFM; Costa & McCrae, 1992) of personality has predominantly focused on the traits of Agreeableness and Extraversion. The characteristics of the other three FFM traits: Neuroticism, Openness, and Conscientiousness…
Structural convergence properties of amorphous InGaZnO4 from simulated liquid-quench methods.
Buchanan, Jacob C; Fast, Dylan B; Hanken, Benjamin E; Mustard, Thomas J L; Laurita, Geneva; Chiang, Tsung-Han; Keszler, Douglas A; Subramanian, Mas A; Wager, John F; Dolgos, Michelle R; Rustad, James R; Cheong, Paul Ha-Yeon
2017-11-14
The study of structural properties of amorphous structures is complicated by the lack of long-range order and necessitates the use of both cutting-edge computer modeling and experimental techniques. With regards to the computer modeling, many questions on convergence arise when trying to assess the accuracy of a simulated system. What cell size maximizes the accuracy while remaining computationally efficient? More importantly, does averaging multiple smaller cells adequately describe features found in bulk amorphous materials? How small is too small? The aims of this work are: (1) to report a newly developed set of pair potentials for InGaZnO 4 and (2) to explore the effects of structural parameters such as simulation cell size and numbers on the structural convergence of amorphous InGaZnO 4 . The total number of formula units considered over all runs is found to be the critical factor in convergence as long as the cell considered contains a minimum of circa fifteen formula units. There is qualitative agreement between these simulations and X-ray total scattering data - peak trends and locations are consistently reproduced while intensities are weaker. These new IGZO pair potentials are a valuable starting point for future structural refinement efforts.
Burns, G Leonard; Walsh, James A; Servera, Mateu; Lorenzo-Seva, Urbano; Cardo, Esther; Rodríguez-Fornells, Antoni
2013-01-01
Exploratory structural equation modeling (SEM) was applied to a multiple indicator (26 individual symptom ratings) by multitrait (ADHD-IN, ADHD-HI and ODD factors) by multiple source (mothers, fathers and teachers) model to test the invariance, convergent and discriminant validity of the Child and Adolescent Disruptive Behavior Inventory with 872 Thai adolescents and the ADHD Rating Scale-IV and ODD scale of the Disruptive Behavior Inventory with 1,749 Spanish children. Most of the individual ADHD/ODD symptoms showed convergent and discriminant validity with the loadings and thresholds being invariant over mothers, fathers and teachers in both samples (the three latent factor means were higher for parents than teachers). The ADHD-IN, ADHD-HI and ODD latent factors demonstrated convergent and discriminant validity between mothers and fathers within the two samples. Convergent and discriminant validity between parents and teachers for the three factors was either absent (Thai sample) or only partial (Spanish sample). The application of exploratory SEM to a multiple indicator by multitrait by multisource model should prove useful for the evaluation of the construct validity of the forthcoming DSM-V ADHD/ODD rating scales.
Mandracchia, Jon T; Morgan, Robert D
2011-12-01
The Measure of Offender Thinking Styles (MOTS) was originally developed to examine the structure of dysfunctional thinking exhibited by criminal offenders. In the initial investigation, a three-factor model of criminal thinking was obtained using the MOTS. These factors included dysfunctional thinking characterized as Control, Cognitive Immaturity, and Egocentrism. In the present investigation, the stability of the three-factor model was examined with a confirmatory factor analysis of the revised version of the MOTS (i.e., MOTS-R). In addition, the internal consistency, test-retest reliability, and convergent validity of the MOTS-R were examined. Results indicated that the three-factor model of criminal thinking was supported. In addition, the MOTS-R demonstrated reliability and convergent validity with other measures of criminal thinking and attitudes. Overall, it appears that the MOTS-R may prove to be a valuable tool for use with an offender population, particularly because of the simple, intuitive structure of dysfunctional thinking that it represents.
Factor structure and psychometric properties of the Fertility Problem Inventory–Short Form
Zurlo, Maria Clelia; Cattaneo Della Volta, Maria Franscesca; Vallone, Federica
2017-01-01
The study analyses factor structure and psychometric properties of the Italian version of the Fertility Problem Inventory–Short Form. A sample of 206 infertile couples completed the Italian version of Fertility Problem Inventory (46 items) with demographics, State Anxiety Scale of State-Trait Anxiety Inventory (Form Y), Edinburgh Depression Scale and Dyadic Adjustment Scale, used to assess convergent and discriminant validity. Confirmatory factor analysis was unsatisfactory (comparative fit index = 0.87; Tucker-Lewis Index = 0.83; root mean square error of approximation = 0.17), and Cronbach’s α (0.95) revealed a redundancy of items. Exploratory factor analysis was carried out deleting cross-loading items, and Mokken scale analysis was applied to verify the items homogeneity within the reduced subscales of the questionnaire. The Fertility Problem Inventory–Short Form consists of 27 items, tapping four meaningful and reliable factors. Convergent and discriminant validity were confirmed. Findings indicated that the Fertility Problem Inventory–Short Form is a valid and reliable measure to assess infertility-related stress dimensions. PMID:29379625
ERIC Educational Resources Information Center
Zimmermann, Gregoire; Mahaim, Elodie Biermann; Mantzouranis, Gregory; Genoud, Philippe A.; Crocetti, Elisabetta
2012-01-01
The purpose of this study was to evaluate the factor structure and the reliability of the French versions of the Identity Style Inventory (ISI-3) and the Utrecht-Management of Identity Commitments Scale (U-MICS) in a sample of college students (N = 457, 18-25 years old). Confirmatory factor analyses confirmed the hypothesized three-factor solution…
Merz, Erin L; Kwakkenbos, Linda; Carrier, Marie-Eve; Gholizadeh, Shadi; Mills, Sarah D; Fox, Rina S; Jewett, Lisa R; Williamson, Heidi; Harcourt, Diana; Assassi, Shervin; Furst, Daniel E; Gottesman, Karen; Mayes, Maureen D; Moss, Tim P; Thombs, Brett D; Malcarne, Vanessa L
2018-01-01
Objective Valid measures of appearance concern are needed in systemic sclerosis (SSc), a rare, disfiguring autoimmune disease. The Derriford Appearance Scale-24 (DAS-24) assesses appearance-related distress related to visible differences. There is uncertainty regarding its factor structure, possibly due to its scoring method. Design Cross-sectional survey. Setting Participants with SSc were recruited from 27 centres in Canada, the USA and the UK. Participants who self-identified as having visible differences were recruited from community and clinical settings in the UK. Participants Two samples were analysed (n=950 participants with SSc; n=1265 participants with visible differences). Primary and secondary outcome measures The DAS-24 factor structure was evaluated using two scoring methods. Convergent validity was evaluated with measures of social interaction anxiety, depression, fear of negative evaluation, social discomfort and dissatisfaction with appearance. Results When items marked by respondents as ‘not applicable’ were scored as 0, per standard DAS-24 scoring, a one-factor model fit poorly; when treated as missing data, the one-factor model fit well. Convergent validity analyses revealed strong correlations that were similar across scoring methods. Conclusions Treating ‘not applicable’ responses as missing improved the measurement model, but did not substantively influence practical inferences that can be drawn from DAS-24 scores. Indications of item redundancy and poorly performing items suggest that the DAS-24 could be improved and potentially shortened. PMID:29511009
The Self-Description Inventory+, Part 1: Factor Structure and Convergent Validity Analyses
2013-07-01
measures 12 scales of personality. The current report examines the possibility of replacing the EQ with a Five Factor Model ( FFM ) measure of...Checklist. Our results show that the SDI + has scales that are intercorrelated in a manner consistent with the FFM (Experiment 1), a factor structure...met the criteria showing it to be an FFM instrument, we will conduct concurrent validity research to determine if the SDI+ has greater predictive
Crawford, John R; Henry, Julie D
2003-06-01
To provide UK normative data for the Depression Anxiety and Stress Scale (DASS) and test its convergent, discriminant and construct validity. Cross-sectional, correlational and confirmatory factor analysis (CFA). The DASS was administered to a non-clinical sample, broadly representative of the general adult UK population (N = 1,771) in terms of demographic variables. Competing models of the latent structure of the DASS were derived from theoretical and empirical sources and evaluated using confirmatory factor analysis. Correlational analysis was used to determine the influence of demographic variables on DASS scores. The convergent and discriminant validity of the measure was examined through correlating the measure with two other measures of depression and anxiety (the HADS and the sAD), and a measure of positive and negative affectivity (the PANAS). The best fitting model (CFI =.93) of the latent structure of the DASS consisted of three correlated factors corresponding to the depression, anxiety and stress scales with correlated error permitted between items comprising the DASS subscales. Demographic variables had only very modest influences on DASS scores. The reliability of the DASS was excellent, and the measure possessed adequate convergent and discriminant validity Conclusions: The DASS is a reliable and valid measure of the constructs it was intended to assess. The utility of this measure for UK clinicians is enhanced by the provision of large sample normative data.
ERIC Educational Resources Information Center
Macmann, Gregg M.; Barnett, David W.
1994-01-01
Describes exploratory and confirmatory analyses of verbal-performance procedures to illustrate concepts and procedures for analysis of correlated factors. Argues that, based on convergent and discriminant validity criteria, factors should have higher correlations with variables that they purport to measure than with other variables. Discusses…
Further development of the talent development environment questionnaire for sport.
Li, Chunxiao; Wang, Chee Keng John; Pyun, Do Young; Martindale, Russell
2015-01-01
Given the significance of monitoring the critical environmental factors that facilitate athlete performance, this two-phase research aimed to validate and refine the revised talent development environment questionnaire (TDEQ). The TDEQ is a multidimensional self-report scale that assesses talented athletes' environmental experiences. Study 1 (the first phase) involved the examination of the revised TDEQ through an exploratory factor analysis (n = 363). This exploratory investigation identified a 28-item five-factor structure (i.e., TDEQ-5) with adequate internal consistency. Study 2 (the second phase) examined the factorial structure of the TDEQ-5, including convergent validity, discriminant validity, and group invariance (i.e., gender and sports type). The second phase was carried out with 496 talented athletes through the application of confirmatory factor analyses and multigroup invariance tests. The results supported the convergent validity, discriminant validity, and group invariance of the TDEQ-5. In conclusion, the TDEQ-5 with 25 items appears to be a reliable and valid scale for use in talent development environments.
The Disgust Scale: Item Analysis, Factor Structure, and Suggestions for Refinement
ERIC Educational Resources Information Center
Olatunji, Bunmi O.; Williams, Nathan L.; Tolin, David F.; Abramowitz, Jonathan S.; Sawchuk, Craig N.; Lohr, Jeffrey M.; Elwood, Lisa S.
2007-01-01
In the 4 studies presented (N = 1,939), a converging set of analyses was conducted to evaluate the item adequacy, factor structure, reliability, and validity of the Disgust Scale (DS; J. Haidt, C. McCauley, & P. Rozin, 1994). The results suggest that 7 items (i.e., Items 2, 7, 8, 21, 23, 24, and 25) should be considered for removal from the DS.…
Gunn, Sarah; Burgess, Gerald H; Maltby, John
2018-04-30
To explore the factor structure of the UK Functional Independence Measure and Functional Assessment Measure (FIM+FAM) among focal and diffuse acquired brain injury patients. Criterion standard. A National Health Service acute acquired brain injury inpatient rehabilitation hospital. Referred sample of N=447 adults admitted for inpatient treatment following an acquired brain injury significant enough to justify intensive inpatient neurorehabilitation INTERVENTION: Not applicable. Functional Independence Measure and Functional Assessment Measure. Exploratory factor analysis suggested a 2-factor structure to FIM+FAM scores, among both focal-proximate and diffuse-proximate acquired brain injury aetiologies. Confirmatory factor analysis suggested a 3-factor bifactor structure presented the best fit of the FIM+FAM score data across both aetiologies. However, across both analyses, a convergence was found towards a general factor, demonstrated by high correlations between factors in the exploratory factor analysis, and by a general factor explaining the majority of the variance in scores on confirmatory factor analysis. Our findings suggested that although factors describing specific functional domains can be derived from FIM+FAM item scores, there is a convergence towards a single factor describing overall functioning. This single factor informs the specific group factors (eg, motor, psychosocial, and communication function) after brain injury. Further research into the comparative value of the general and group factors as evaluative/prognostic measures is indicated. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
The reasons for betel-quid chewing scale: assessment of factor structure, reliability, and validity
2014-01-01
Background Despite the fact that betel-quid is one of the most commonly used psychoactive substances worldwide and a major risk-factor for head-and-neck cancer incidence and mortality globally, currently no standardized instrument is available to assess the reasons why individuals chew betel-quid. A measure to assess reasons for chewing betel-quid could help researchers and clinicians develop prevention and treatment strategies. In the current study, we sought to develop and evaluate a self-report instrument for assessing the reasons for chewing betel quid which contributes toward the goal of developing effective interventions to reduce betel quid chewing in vulnerable populations. Methods The current study assessed the factor structure, reliability and convergent validity of the Reasons for Betel-quid Chewing Scale (RBCS), a newly developed 10 item measure adapted from several existing “reasons for smoking” scales. The measure was administered to 351 adult betel-quid chewers in Guam. Results Confirmatory factor analysis of this measure revealed a three factor structure: reinforcement, social/cultural, and stimulation. Further tests revealed strong support for the internal consistency and convergent validity of this three factor measure. Conclusion The goal of designing an intervention to reduce betel-quid chewing necessitates an understanding of why chewers chew; the current study makes considerable contributions towards that objective. PMID:24889863
The reasons for betel-quid chewing scale: assessment of factor structure, reliability, and validity.
Little, Melissa A; Pokhrel, Pallav; Murphy, Kelle L; Kawamoto, Crissy T; Suguitan, Gil S; Herzog, Thaddeus A
2014-06-03
Despite the fact that betel-quid is one of the most commonly used psychoactive substances worldwide and a major risk-factor for head-and-neck cancer incidence and mortality globally, currently no standardized instrument is available to assess the reasons why individuals chew betel-quid. A measure to assess reasons for chewing betel-quid could help researchers and clinicians develop prevention and treatment strategies. In the current study, we sought to develop and evaluate a self-report instrument for assessing the reasons for chewing betel quid which contributes toward the goal of developing effective interventions to reduce betel quid chewing in vulnerable populations. The current study assessed the factor structure, reliability and convergent validity of the Reasons for Betel-quid Chewing Scale (RBCS), a newly developed 10 item measure adapted from several existing "reasons for smoking" scales. The measure was administered to 351 adult betel-quid chewers in Guam. Confirmatory factor analysis of this measure revealed a three factor structure: reinforcement, social/cultural, and stimulation. Further tests revealed strong support for the internal consistency and convergent validity of this three factor measure. The goal of designing an intervention to reduce betel-quid chewing necessitates an understanding of why chewers chew; the current study makes considerable contributions towards that objective.
Large Covariance Estimation by Thresholding Principal Orthogonal Complements
Fan, Jianqing; Liao, Yuan; Mincheva, Martina
2012-01-01
This paper deals with the estimation of a high-dimensional covariance with a conditional sparsity structure and fast-diverging eigenvalues. By assuming sparse error covariance matrix in an approximate factor model, we allow for the presence of some cross-sectional correlation even after taking out common but unobservable factors. We introduce the Principal Orthogonal complEment Thresholding (POET) method to explore such an approximate factor structure with sparsity. The POET estimator includes the sample covariance matrix, the factor-based covariance matrix (Fan, Fan, and Lv, 2008), the thresholding estimator (Bickel and Levina, 2008) and the adaptive thresholding estimator (Cai and Liu, 2011) as specific examples. We provide mathematical insights when the factor analysis is approximately the same as the principal component analysis for high-dimensional data. The rates of convergence of the sparse residual covariance matrix and the conditional sparse covariance matrix are studied under various norms. It is shown that the impact of estimating the unknown factors vanishes as the dimensionality increases. The uniform rates of convergence for the unobserved factors and their factor loadings are derived. The asymptotic results are also verified by extensive simulation studies. Finally, a real data application on portfolio allocation is presented. PMID:24348088
Large Covariance Estimation by Thresholding Principal Orthogonal Complements.
Fan, Jianqing; Liao, Yuan; Mincheva, Martina
2013-09-01
This paper deals with the estimation of a high-dimensional covariance with a conditional sparsity structure and fast-diverging eigenvalues. By assuming sparse error covariance matrix in an approximate factor model, we allow for the presence of some cross-sectional correlation even after taking out common but unobservable factors. We introduce the Principal Orthogonal complEment Thresholding (POET) method to explore such an approximate factor structure with sparsity. The POET estimator includes the sample covariance matrix, the factor-based covariance matrix (Fan, Fan, and Lv, 2008), the thresholding estimator (Bickel and Levina, 2008) and the adaptive thresholding estimator (Cai and Liu, 2011) as specific examples. We provide mathematical insights when the factor analysis is approximately the same as the principal component analysis for high-dimensional data. The rates of convergence of the sparse residual covariance matrix and the conditional sparse covariance matrix are studied under various norms. It is shown that the impact of estimating the unknown factors vanishes as the dimensionality increases. The uniform rates of convergence for the unobserved factors and their factor loadings are derived. The asymptotic results are also verified by extensive simulation studies. Finally, a real data application on portfolio allocation is presented.
ERIC Educational Resources Information Center
Miller, Joshua D.; Gaughan, Eric T.; Pryor, Lauren R.
2008-01-01
There are several self-report measures of psychopathy, most of which use a two-factor structure. There is debate regarding the convergence of these factors, particularly with regard to Factor 1 (F1), which is related to the interpersonal and affective aspects of psychopathy; Factor 2 (F2) is related to the social deviance associated with…
Helle, Ashley C; Trull, Timothy J; Widiger, Thomas A; Mullins-Sweatt, Stephanie N
2017-07-01
An alternative model for personality disorders is included in Section III (Emerging Models and Measures) of Diagnostic and Statistical Manual of Mental Disorders, (5th ed.; DSM-5). The DSM-5 dimensional trait model is an extension of the Five-Factor Model (FFM; American Psychiatric Association, 2013). The Personality Inventory for DSM-5 (PID-5) assesses the 5 domains and 25 traits in the alternative model. The current study expands on recent research to examine the relationship of the PID-5 with an interview measure of the FFM. The Structured Interview for the Five Factor Model of Personality (SIFFM) assesses the 5 bipolar domains and 30 facets of the FFM. Research has indicated that the SIFFM captures maladaptive aspects of personality (as well as adaptive). The SIFFM, NEO PI-R, and PID-5 were administered to participants to examine their respective convergent and discriminant validity. Results provide evidence for the convergence of the 2 models using self-report and interview measures of the FFM. Clinical implications and future directions are discussed, particularly a call for the development of a structured interview for the assessment of the DSM-5 dimensional trait model. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Convergent and Discriminant Validity of the Five Factor Form and the Sliderbar Inventory.
Rojas, Stephanie L; Widiger, Thomas A
2018-03-01
Existing measures of the five factor model (FFM) of personality are generally, if not exclusively, unipolar in their assessment of maladaptive variants of the FFM domains. However, two recently developed measures, the Five Factor Form (FFF) and the Sliderbar Inventory (SI), include items that assess for maladaptive variants at both poles of each item. This structure is unique among existing measures of personality and personality disorder, although there is a historical, infrequently used Stone Personality Trait Schema (SPTS) that had also included this item structure. To facilitate an exploration of their convergent and discriminant validity, the SI and SPTS items were reorganized into FFM scales. The convergent and discriminant validity of the FFF, SI-FFM, and SPTS-FFM scales was considered in a sample of 450 adults with current or a history of mental health treatment. The FFF, SI-FFM, and SPTS-FFM were also compared with respect to their relationship with FFM domains. Finally, the FFF items and SI-FFM scales were tested with respect to their relationship with measures of maladaptive variants of both high and low agreeableness and conscientiousness. The implications of the results are discussed with respect to the assessment of maladaptive personality functioning, and suggestions for future research are provided.
Lalanne, Christophe; Chassany, Olivier; Carrieri, Patrizia; Marcellin, Fabienne; Armstrong, Andrew R; Lert, France; Spire, Bruno; Dray-Spira, Rosemary; Duracinsky, Martin
2016-04-01
To identify a simplified factor structure for the PROQOL-human immunodeficiency virus (HIV) questionnaire to improve the measurement of the health-related quality of life (HRQL) of HIV-positive patients in clinical care and research settings. HRQL data were collected using the eight-dimension PROQOL-HIV questionnaire from 2,537 patients (VESPA2 study). Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) validated a simpler four-factor structure and assessed measurement invariance (MI). Multigroup analysis assessed the effect of sex, age, and antiretroviral therapy (ART) on the resulting factor scores. Correlations with symptom and Short Form (SF)-12 self-reports assessed convergent validity. Item analysis, EFA, and CFAs confirmed the validity [comparative fit index (CFI), 0.948; root mean square error of approximation, 0.064] and reliability (α's ≥ 0.8) of four dimensions: physical health and symptoms, health concerns and mental distress, social and intimate relationships, and treatment-related impact. Strong MI was demonstrated across sex and age (decrease in CFI <0.01). A multiple-cause multiple-indicator model indicated that HRQL correlated as expected with sex, age, and the ART status. Correlations of HRQL, symptom reports, and SF-12 scores evidenced convergent validity criterion. The simplified factor structure and scoring scheme for PROQOL-HIV will allow clinicians to monitor with greater reliability the HRQL of patients in clinical care and research settings. Copyright © 2016 Elsevier Inc. All rights reserved.
How counterfactuals of Red-Queen theory shed light on science and its historiography.
Dagg, Joachim L
2017-08-01
A historical episode of evolutionary theory, which has lead to the Red Queen theory of the evolutionary maintenance of sex, includes two striking contingencies. These are used to explore alternative what-if scenarios, in order to test some common opinions about such counterfactuals. This sheds new light on the nature of science and its historiography. One counterfactual leads to an unexpected convergence of its result to that of the actual science but, nevertheless, differs in its causal structure. The other diverges towards an incompatible alternative, but this requires further contingent choices that also diverge from actual science. The convergence in the first counterfactual is due to a horizontal transfer of knowledge. Similar transfers of knowledge are typical for innovations of actual science. This suggests that contingent choices can merge as well as fork research traditions both in actual research and counterfactual history. Neither the paths of the actual history of science nor those of its counterfactual alternatives will form a tree of exclusively diverging bifurcations, but a network instead. Convergencies in counterfactuals may, therefore, be due to the web-structure of science as much as to the aims of the historians in question. Furthermore, the difference in causal structure between the actual science and its convergent counterfactual might become diagnostic for external factors rather than internal aims forcing a historian towards convergence. Copyright © 2017 Elsevier Ltd. All rights reserved.
Nelis, Sabine; Holmes, Emily A.; Griffith, James W.; Raes, Filip
2015-01-01
The Spontaneous Use of Imagery Scale (SUIS) is used to measure the tendency to use visual mental imagery in daily life. Its psychometric properties were evaluated in three independent samples (total N = 1297). We evaluated the internal consistency and test-retest reliability of the questionnaire. We also examined the structure of the items using exploratory and confirmatory factor analysis. Moreover, correlations with other imagery questionnaires provided evidence about convergent validity. The SUIS had acceptable reliability and convergent validity. Exploratory and confirmatory factor analysis revealed that a unidimensional structure fit the data, suggesting that the SUIS indeed measures a general use of mental imagery in daily life. Future research can further investigate and improve the psychometric properties of the SUIS. Moreover, the SUIS could be useful to determine how imagery relates to e.g. psychopathology. PMID:26290615
Mucci, A; Galderisi, S; Merlotti, E; Rossi, A; Rocca, P; Bucci, P; Piegari, G; Chieffi, M; Vignapiano, A; Maj, M
2015-07-01
The Brief Negative Symptom Scale (BNSS) was developed to address the main limitations of the existing scales for the assessment of negative symptoms of schizophrenia. The initial validation of the scale by the group involved in its development demonstrated good convergent and discriminant validity, and a factor structure confirming the two domains of negative symptoms (reduced emotional/verbal expression and anhedonia/asociality/avolition). However, only relatively small samples of patients with schizophrenia were investigated. Further independent validation in large clinical samples might be instrumental to the broad diffusion of the scale in clinical research. The present study aimed to examine the BNSS inter-rater reliability, convergent/discriminant validity and factor structure in a large Italian sample of outpatients with schizophrenia. Our results confirmed the excellent inter-rater reliability of the BNSS (the intraclass correlation coefficient ranged from 0.81 to 0.98 for individual items and was 0.98 for the total score). The convergent validity measures had r values from 0.62 to 0.77, while the divergent validity measures had r values from 0.20 to 0.28 in the main sample (n=912) and in a subsample without clinically significant levels of depression and extrapyramidal symptoms (n=496). The BNSS factor structure was supported in both groups. The study confirms that the BNSS is a promising measure for quantifying negative symptoms of schizophrenia in large multicenter clinical studies. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Chan, Kin Sun
2018-01-01
Objectives This study aimed to evaluate the internal consistency, reliability, convergent validity, known-group comparisons, and structural validity of the Chinese version of Fear of Intimacy with Helping Professionals (C–FIS–HP) scale in Macau. Methods A cross-sectional design was used on a sample of 593 older people in 6 health centers. We used Chinese version of Exercise of Self-Care Agency Scale (C-ESCAS) and Morisky 4-item medication adherence scale to evaluate self-care actions and medication adherence. The internal consistency and reliability of C–FIS–HP were analyzed using the Spearman-Brown split-half reliability, Cronbach’s alpha, and test–retest reliability. Convergent validity was tested the construct of C–FIS–HP and self-care actions. Known-group comparisons differentiated predefined groups in an expected direction. Two separated samples were used to test the structural validity. An exploratory factor analysis (EFA) tested the factor structure of C–FISHP using the principal axis factoring. A confirmatory factor analysis (CFA) was further conducted to confirm the factor structure constructed in the prior EFA. Results The C–FIS–HP had a Spearman-Brown split-half coefficient, Cronbach’s alpha, and intraclass correlation coefficient of 0.96, 0.93, and 0.96, respectively. Convergent validity was satisfactory with significantly correlations between the C-FIS-HP and C-ESCAS. C–FIS–HP to differentiate the differences between high-, moderate-, and low- medication adherence groups. EFA demonstrated a two-factor structure among 297 older people. A first-order CFA was performed to confirm the construct dimensionality of C–FIS–HP with satisfactory fit indices (NFI = 0.92; IFI = 0.95; TLI = 0.94; CFI = 0.95 and RMSEA = 0.07) among 296 older people. Conclusions C–FIS–HP is a reliable and valid test for assessing helping relationships in older Chinese people. Health professionals can use C–FIS–HP as a clinical tool to assess the comfort level of patients in a helping relationship, and use this information to develop culturally sensitive therapeutic interventions and treatment plans. Further studies need to be conducted concerning the different psychometric properties, as well as the application of C–FIS–HP in various regions. PMID:29795563
ERIC Educational Resources Information Center
Yang, Hongfei; Hai, Tang
2015-01-01
The psychometrics of the Chinese Solution-Focused Inventory (CSFI) was studied in Chinese college students. Confirmatory factor analysis confirmed the 3-factor structure. All subscales showed good reliability and convergent and incremental validity. Results of hierarchical regression analyses indicated that the 3 subscales accounted for additional…
A Five-Factor Measure of Schizotypal Personality Traits
ERIC Educational Resources Information Center
Edmundson, Maryanne; Lynam, Donald R.; Miller, Joshua D.; Gore, Whitney L.; Widiger, Thomas A.
2011-01-01
The current study provides convergent, discriminant, and incremental validity data for a new measure of schizotypy from the perspective of the five-factor model (FFM) of general personality structure. Nine schizotypy scales were constructed as maladaptive variants of respective facets of the FFM (e.g., Aberrant Ideas as a maladaptive variant of…
ERIC Educational Resources Information Center
Olatunji, Bunmi O.; Broman-Fulks, Joshua J.
2007-01-01
Disgust sensitivity has recently been implicated as a specific vulnerability factor for several anxiety-related disorders. However, it is not clear whether disgust sensitivity is a dimensional or categorical phenomenon. The present study examined the latent structure of disgust by applying three taxometric procedures (maximum eigenvalue, mean…
Comparing short forms of the Social Interaction Anxiety Scale and the Social Phobia Scale.
Carleton, R Nicholas; Thibodeau, Michel A; Weeks, Justin W; Teale Sapach, Michelle J N; McEvoy, Peter M; Horswill, Samantha C; Heimberg, Richard G
2014-12-01
The Social Interaction Anxiety Scale (SIAS) and the Social Phobia Scale (SPS; Mattick & Clarke, 1998) are companion scales developed to measure anxiety in social interaction and performance situations, respectively. The measures have strong discriminant and convergent validity; however, their factor structures remain debated, and furthermore, the combined administration length (i.e., 39 items) can be prohibitive for some settings. There have been 4 attempts to assess the factor structures of the scales and reduce the item content: the 14-item Social Interaction Phobia Scale (SIPS; Carleton et al., 2009), the 12-item SIAS-6/SPS-6 (Peters, Sunderland, Andrews, Rapee, & Mattick, 2012), the 21-item abbreviated SIAS/SPS (ASIAS/ASPS; Kupper & Denollet, 2012), and the 12-item Readability SIAS and SPS (RSIAS/RSPS; Fergus, Valentiner, McGrath, Gier-Lonsway, & Kim, 2012). The current study compared the short forms on (a) factor structure, (b) ability to distinguish between clinical and non-clinical populations, (c) sensitivity to change following therapy, and (d) convergent validity with related measures. Participants included 3,607 undergraduate students (55% women) and 283 patients with social anxiety disorder (43% women). Results of confirmatory factor analyses, sensitivity analyses, and correlation analyses support the robust utility of items in the SIPS and the SPS-6 and SIAS-6 relative to the other short forms; furthermore, the SIPS and the SPS-6 and SIAS-6 were also supported by convergent validity analyses within the undergraduate sample. The RSIAS/RSPS and the ASIAS/ASPS were least supported, based on the current results and the principle of parsimony. Accordingly, researchers and clinicians should consider carefully which of the short forms will best suit their needs. (c) 2014 APA, all rights reserved.
ERIC Educational Resources Information Center
Samuel, Douglas B.; Mullins-Sweatt, Stephanie N.; Widiger, Thomas A.
2013-01-01
The Five-Factor Model Rating Form (FFMRF) is a one-page measure designed to provide an efficient assessment of the higher order domains of the Five Factor Model (FFM) as well as the more specific, lower order facets proposed by McCrae and Costa. Although previous research has suggested that the FFMRF's assessment of the lower order facets converge…
Factor structure and validity of the Depression, Anxiety and Stress Scale-21 in Swedish translation.
Alfonsson, S; Wallin, E; Maathz, P
2017-03-01
WHAT IS KNOWN ON THE SUBJECT?: The Depression, Anxiety and Stress Scale-21 (DASS-21) is a widely used measurement for psychological symptoms and distress. Some previous studies have shown that the DASS-21 can accurately measure symptoms of anxiety, depression and stress, while other studies have indicated that the DASS-21 mainly measures overall distress. The factor structure of the DASS-21 is important and debated since if affects interpretations of findings. WHAT DOES THIS PAPER ADD TO EXISTING KNOWLEDGE?: In this study, the DASS-21 was translated into Swedish and evaluated in three diverse samples. The DASS-21 subscales of Depression and Anxiety correlated significantly with corresponding criteria instruments. The DASS-21 Stress subscale showed more diverse associations with psychological distress. The analyses supported a bifactor model of the DASS-21 with three specific factors of depression, anxiety and stress as well as a general distress factor. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: The results show that the DASS-21 may be used to measure unique symptoms of depression, anxiety and, with some caveat, stress as well as overall psychological distress. This study confirms that the DASS-21 is theoretically sound instrument that is feasible for both research and clinical practice. The DASS-21 can be an accessible tool for screening and evaluation in first-line mental health services. Introduction There is a constant need for theoretically sound and valid self-report instruments for measuring psychological distress. Previous studies have shown that the Depression, Anxiety and Stress Scale-21 (DASS-21) is theoretically sound, but there have been some inconsistent results regarding its factor structure. Aims The aim of the present study was to investigate and elucidate the factor structure and convergent validity of the DASS-21. Methods A total of 624 participants recruited from student, primary care and psychotherapy populations. The factor structure of the DASS-21 was assessed by confirmatory factor analyses and the convergent validity by investigating its unique correlations with other psychiatric instruments. Results A bifactor structure with depression, anxiety, stress and a general factor provided the best fit indices for the DASS-21. The convergent validity was adequate for the Depression and Anxiety subscales but more ambiguous for the Stress subscale. Discussion The present study overall supports the validity and factor structure of the DASS-21. Implications for practice The DASS-21 can be used to measure symptoms of depression and anxiety as well as overall distress. It can be useful for mental health nurses, and other first-line psychiatric professionals, in need of a short, feasible and valid instrument in everyday care. © 2017 John Wiley & Sons Ltd.
Ehrhart, Mark G.; Torres, Elisa M.; Finn, Natalie K.; Roesch, Scott C.
2016-01-01
There have been recent calls for pragmatic measures to assess factors that influence evidence-based practice (EBP) implementation processes and outcomes. The Implementation Leadership Scale (ILS) is a brief and efficient measure that can be used for research or organizational development purposes to assess leader behaviors and actions that actively support effective EBP implementation. The ILS was developed and validated in mental health settings. This study validates the ILS factor structure with providers in alcohol and other drug (AOD) use treatment agencies. Participants were 323 service providers working in 72 workgroups from three AOD use treatment agencies. Confirmatory factor analyses and reliability analyses were conducted to examine the psychometric properties of the ILS. Convergent and discriminant validity were also assessed. Confirmatory factor analyses demonstrated good fit to the hypothesized first and second order factor structure. Internal consistency reliability was excellent. Convergent and discriminant validity was supported. The ILS psychometric characteristics, reliability, and validity were supported in AOD use treatment agencies. The ILS is a brief and pragmatic measure that can be used for research and practice to assess leadership for EBP implementation in AOD use treatment agencies. PMID:27431044
Aarons, Gregory A; Ehrhart, Mark G; Torres, Elisa M; Finn, Natalie K; Roesch, Scott C
2016-09-01
There have been recent calls for pragmatic measures to assess factors that influence evidence-based practice (EBP) implementation processes and outcomes. The Implementation Leadership Scale (ILS) is a brief and efficient measure that can be used for research or organizational development purposes to assess leader behaviors and actions that actively support effective EBP implementation. The ILS was developed and validated in mental health settings. This study validates the ILS factor structure with providers in alcohol and other drug (AOD) use treatment agencies. Participants were 323 service providers working in 72 workgroups from three AOD use treatment agencies. Confirmatory factor analyses and reliability analyses were conducted to examine the psychometric properties of the ILS. Convergent and discriminant validity were also assessed. Confirmatory factor analyses demonstrated good fit to the hypothesized first and second order factor structure. Internal consistency reliability was excellent. Convergent and discriminant validity was supported. The ILS psychometric characteristics, reliability, and validity were supported in AOD use treatment agencies. The ILS is a brief and pragmatic measure that can be used for research and practice to assess leadership for EBP implementation in AOD use treatment agencies. Copyright © 2016 Elsevier Inc. All rights reserved.
Did Convergent Protein Evolution Enable Phytoplasmas to Generate 'Zombie Plants'?
Rümpler, Florian; Gramzow, Lydia; Theißen, Günter; Melzer, Rainer
2015-12-01
Phytoplasmas are pathogenic bacteria that reprogram plant development such that leaf-like structures instead of floral organs develop. Infected plants are sterile and mainly serve to propagate phytoplasmas and thus have been termed 'zombie plants'. The developmental reprogramming relies on specific interactions of the phytoplasma protein SAP54 with a small subset of MADS-domain transcription factors. Here, we propose that SAP54 folds into a structure that is similar to that of the K-domain, a protein-protein interaction domain of MADS-domain proteins. We suggest that undergoing convergent structural and sequence evolution, SAP54 evolved to mimic the K-domain. Given the high specificity of resulting developmental alterations, phytoplasmas might be used to study flower development in genetically intractable plants. Copyright © 2015 Elsevier Ltd. All rights reserved.
Grid Convergence for Turbulent Flows(Invited)
NASA Technical Reports Server (NTRS)
Diskin, Boris; Thomas, James L.; Rumsey, Christopher L.; Schwoppe, Axel
2015-01-01
A detailed grid convergence study has been conducted to establish accurate reference solutions corresponding to the one-equation linear eddy-viscosity Spalart-Allmaras turbulence model for two dimensional turbulent flows around the NACA 0012 airfoil and a flat plate. The study involved three widely used codes, CFL3D (NASA), FUN3D (NASA), and TAU (DLR), and families of uniformly refined structured grids that differ in the grid density patterns. Solutions computed by different codes on different grid families appear to converge to the same continuous limit, but exhibit different convergence characteristics. The grid resolution in the vicinity of geometric singularities, such as a sharp trailing edge, is found to be the major factor affecting accuracy and convergence of discrete solutions, more prominent than differences in discretization schemes and/or grid elements. The results reported for these relatively simple turbulent flows demonstrate that CFL3D, FUN3D, and TAU solutions are very accurate on the finest grids used in the study, but even those grids are not sufficient to conclusively establish an asymptotic convergence order.
Mills, Sarah D; Kwakkenbos, Linda; Carrier, Marie-Eve; Gholizadeh, Shadi; Fox, Rina S; Jewett, Lisa R; Gottesman, Karen; Roesch, Scott C; Thombs, Brett D; Malcarne, Vanessa L
2018-01-17
Systemic sclerosis (SSc) is an autoimmune disease that can cause disfiguring changes in appearance. This study examined the structural validity, internal consistency reliability, convergent validity, and measurement equivalence of the Social Appearance Anxiety Scale (SAAS) across SSc disease subtypes. Patients enrolled in the Scleroderma Patient-centered Intervention Network Cohort completed the SAAS and measures of appearance-related concerns and psychological distress. Confirmatory factor analysis (CFA) was used to examine the structural validity of the SAAS. Multiple-group CFA was used to determine if SAAS scores can be compared across patients with limited and diffuse disease subtypes. Cronbach's alpha was used to examine internal consistency reliability. Correlations of SAAS scores with measures of body image dissatisfaction, fear of negative evaluation, social anxiety, and depression were used to examine convergent validity. SAAS scores were hypothesized to be positively associated with all convergent validity measures, with correlations significant and moderate to large in size. A total of 938 patients with SSc were included. CFA supported a one-factor structure (CFI: .92; SRMR: .04; RMSEA: .08), and multiple-group CFA indicated that the scalar invariance model best fit the data. Internal consistency reliability was good in the total sample (α = .96) and in disease subgroups. Overall, evidence of convergent validity was found with measures of body image dissatisfaction, fear of negative evaluation, social anxiety, and depression. The SAAS can be reliably and validly used to assess fear of appearance evaluation in patients with SSc, and SAAS scores can be meaningfully compared across disease subtypes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
ERIC Educational Resources Information Center
Cramer, Robert J.; Burks, Alixandra C.; Golom, Frank D.; Stroud, Caroline H.; Graham, James L.
2017-01-01
We tested the psychometric properties of the Lesbian, Gay, and Bisexual Identity Scale. Findings included (1) a three-factor structure (i.e., Negative Identity, Identity Uncertainty, Identity Superiority); (2) less positive identities among HIV-positive persons, African Americans, males, and bisexuals; and (3) convergent patterns with subjective…
ERIC Educational Resources Information Center
Mayer, Matthew J.
2010-01-01
The 1995-2005 School Crime Supplement datasets were analyzed using structural equation modeling. Converging evidence across multiple analyses suggests that secure school building policies may not be systematically linked to school disorder and may be more a reactive measure in response to other concerns. Most importantly, measures of incivility…
[Factor structure validity of the social capital scale used at baseline in the ELSA-Brasil study].
Souto, Ester Paiva; Vasconcelos, Ana Glória Godoi; Chor, Dora; Reichenheim, Michael E; Griep, Rosane Härter
2016-07-21
This study aims to analyze the factor structure of the Brazilian version of the Resource Generator (RG) scale, using baseline data from the Brazilian Longitudinal Health Study in Adults (ELSA-Brasil). Cross-validation was performed in three random subsamples. Exploratory factor analysis using exploratory structural equation models was conducted in the first two subsamples to diagnose the factor structure, and confirmatory factor analysis was used in the third to corroborate the model defined by the exploratory analyses. Based on the 31 initial items, the model with the best fit included 25 items distributed across three dimensions. They all presented satisfactory convergent validity (values greater than 0.50 for the extracted variance) and precision (values greater than 0.70 for compound reliability). All factor correlations were below 0.85, indicating full discriminative factor validity. The RG scale presents acceptable psychometric properties and can be used in populations with similar characteristics.
Gourounti, K; Anagnostopoulos, F; Vaslamatzis, G
2011-10-01
to examine the psychometric properties of the Fertility Problem Inventory (FPI) originally developed by Newton et al. (1999); as there are no data concerning the factorial structure of the FPI, a special focus is placed on construct validity through factor analysis. public hospital in Athens, Greece. a cross-sectional study. 108 women undergoing fertility treatment with in-vitro fertilisation. the FPI was 'forward-backward' translated from English to Greek. The translated instrument was then administered to a set of infertile women for pilot testing. Principal axis factoring with promax rotation was used to test the factor structure of the FPI. Measures of anxiety State Trait Anxiety Inventory, depression (Center for Epidemiologic Studies--Depression Scale) and mood states Profile of Mood States were used to assess the convergent validity of the FPI. Cronbach's α was used to measure internal consistency of the FPI scales. exploratory factor analysis suggested four factors. The majority of relationship and sexual concern items grouped into one solid factor, named 'spousal concern'. The original scales of social concern, need for parenthood and rejection of childfree lifestyle were reproduced after rearranging nine cross-loading items. Construct validity was confirmed by computing correlations between the derived FPI scales and conceptually similar constructions of anxiety, depression and mood states. Internal consistency reliability was satisfactory. the FPI was found to have a relatively stable factor structure and satisfactory reliability, and convergent and discriminant validity. The FPI may enable researchers and clinicians to apply a reliable measure that focuses on various/many dimensions of infertility-related stress. Copyright © 2010 Elsevier Ltd. All rights reserved.
From rifting to subduction: the role of inheritance in the Wilson Cycle
NASA Astrophysics Data System (ADS)
Beaussier, Stéphane; Gerya, Taras; Burg, Jean-Pierre
2017-04-01
The Wilson Cycle entails that oceans close and reopen. This cycle is a fundamental principle in plate tectonics, inferring continuity from divergence to convergence and that continental rifting takes place along former suture zones. This view questions the role of inherited structures at each stage of the Wilson Cycle. Using the 3D thermo-mechanical code, I3ELVIS (Gerya and Yuen 2007) we present a high-resolution continuous model of the Wilson cycle from continental rifting, breakup and oceanic spreading to convergence and spontaneous subduction initiation. Therefore, all lateral and longitudinal structures of the lithospheres are generated self-consistently and are consequences of the initial continental structure, tectono-magmatic inheritance and material rheology. In the models, subduction systematically initiates off-ridge and is controlled by the convergence-induced swelling of the ridge. Geometry and dynamics of the developing off-ridge subduction is controlled by four main factors: (1) the obliquity of the ridge with respect to the convergence direction; (2) fluid-induced weakening of the oceanic crust; (3) irregularity of ridge and margins inherited from rifting and spreading; (4) strain localization at transform faults formed during ocean floor spreading. Further convergence can lead to obduction of the oceanic crust and segments of ridge after the oceanic lithosphere is entrained into subduction. We show that the main parameters controlling the occurrence and geometry of obducted ophiolite are the convergence rate and the inherited structure of the passive margins and ridge. Our numerical experiments results show the essential role played by inheritance during the Wilson Cycle and are consistent with nature observations such as the tectonic history of the Oman subduction-obduction system. REFERENCES Gerya, T. V., and D. A. Yuen. 2007: "Robust Characteristics Method for Modelling Multiphase Visco-Elasto-Plastic Thermo-Mechanical Problems, Physics of the Earth and Planetary Interiors, 163 (1-4), 83-105.
Sailamul, Pachaya; Jang, Jaeson; Paik, Se-Bum
2017-12-01
Correlated neural activities such as synchronizations can significantly alter the characteristics of spike transfer between neural layers. However, it is not clear how this synchronization-dependent spike transfer can be affected by the structure of convergent feedforward wiring. To address this question, we implemented computer simulations of model neural networks: a source and a target layer connected with different types of convergent wiring rules. In the Gaussian-Gaussian (GG) model, both the connection probability and the strength are given as Gaussian distribution as a function of spatial distance. In the Uniform-Constant (UC) and Uniform-Exponential (UE) models, the connection probability density is a uniform constant within a certain range, but the connection strength is set as a constant value or an exponentially decaying function, respectively. Then we examined how the spike transfer function is modulated under these conditions, while static or synchronized input patterns were introduced to simulate different levels of feedforward spike synchronization. We observed that the synchronization-dependent modulation of the transfer function appeared noticeably different for each convergence condition. The modulation of the spike transfer function was largest in the UC model, and smallest in the UE model. Our analysis showed that this difference was induced by the different spike weight distributions that was generated from convergent synapses in each model. Our results suggest that, the structure of the feedforward convergence is a crucial factor for correlation-dependent spike control, thus must be considered important to understand the mechanism of information transfer in the brain.
Ang, Hui-Gek; Koh, Jeremy Meng-Yeow; Lee, Jeffrey; Pua, Yong-Hao
2016-02-19
No instruments, to our knowledge, exist to assess leadership competency in existing and emerging allied health professional (AHP) leaders. This paper describes the development and preliminary exploration of the psychometric properties of a leadership competency instrument for existing and emerging AHP leaders and examines (i) its factor structure, (ii) its convergent validity with the Leadership Practices Inventory (LPI), and (iii) its discriminative validity in AHPs with different grades. During development, we included 25 items in the AHEAD (Aspiring leaders in Healthcare-Empowering individuals, Achieving excellence, Developing talents) instrument. A cross-sectional study was then conducted in 106 high-potential AHPs from Singapore General Hospital (34 men and 72 women) of different professional grades (49 principal-grade AHPs, 41 senior-grade AHPs, and 16 junior-grade AHPs) who completed both AHEAD and LPI instruments. Exploratory factor analysis was used to test the theoretical structure of AHEAD. Spearman correlation analysis was performed to evaluate the convergent validity of AHEAD with LPI. Using proportional odds regression models, we evaluated the association of grades of AHPs with AHEAD and LPI. To assess discriminative validity, the c-statistics - a measure of discrimination - were derived from these ordinal models. As theorized, factor analysis suggested a two-factor solution, where "skills" and "values" formed separate factors. Internal consistency of AHEAD was excellent (α-values > 0.88). Total and component AHEAD and LPI scores correlated moderately (Spearman ρ-values, 0.37 to 0.58). The c-index for discriminating between AHP grades was higher for AHEAD than for the LPI (0.76 vs. 0.65). The factorial structure of AHEAD was generally supported in our study. AHEAD showed convergent validity with the LPI and outperformed the LPI in terms of discriminative validity. These results provide initial evidence for the use of AHEAD to assess leadership competency in AHPs.
Marsh, Herbert W; Vallerand, Robert J; Lafrenière, Marc-André K; Parker, Philip; Morin, Alexandre J S; Carbonneau, Noémie; Jowett, Sophia; Bureau, Julien S; Fernet, Claude; Guay, Frédéric; Salah Abduljabbar, Adel; Paquet, Yvan
2013-09-01
The passion scale, based on the dualistic model of passion, measures 2 distinct types of passion: Harmonious and obsessive passions are predictive of adaptive and less adaptive outcomes, respectively. In a substantive-methodological synergy, we evaluate the construct validity (factor structure, reliability, convergent and discriminant validity) of Passion Scale responses (N = 3,571). The exploratory structural equation model fit to the data was substantially better than the confirmatory factor analysis solution, and resulted in better differentiated (less correlated) factors. Results from a 13-model taxonomy of measurement invariance supported complete invariance (factor loadings, factor correlations, item uniquenesses, item intercepts, and latent means) over language (French vs. English; the instrument was originally devised in French, then translated into English) and gender. Strong measurement partial invariance over 5 passion activity groups (leisure, sport, social, work, education) indicates that the same set of items is appropriate for assessing passion across a wide variety of activities--a previously untested, implicit assumption that greatly enhances practical utility. Support was found for the convergent and discriminant validity of the harmonious and obsessive passion scales, based on a set of validity correlates: life satisfaction, rumination, conflict, time investment, activity liking and valuation, and perceiving the activity as a passion.
Morsunbul, Umit; Crocetti, Elisabetta; Cok, Figen; Meeus, Wim
2014-08-01
The purpose of this study was to evaluate the factor structure and convergent validity of the Turkish version of the Utrecht-Management of Identity Commitments Scale (U-MICS). Participants were 1201 (59.6% females) youth aged between 12 and 24 years (M(age) = 17.53 years, SD(age) = 3.25). Results indicated that the three-factor model consisting of commitment, in-depth exploration, and reconsideration of commitment provided a very good fit to the data and applied equally well to boys and girls as well as to three age groups (early adolescents, middle adolescents, and emerging adults). Significant relations between identity processes and self-concept clarity, personality, internalizing and externalizing problem behaviors, and parental relationships supported convergent validity. Thus, the Turkish version of U-MICS is a reliable tool for assessing identity in Turkish-speaking respondents. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Biringer, Eva; Tjoflåt, Marit
2018-01-25
The Recovery Assessment Scale-revised (RAS-R) is a self-report instrument measuring mental health recovery. The purpose of the present study was to translate and adapt the RAS-R into the Norwegian language and to investigate its psychometric properties in terms of factor structure, convergent and discriminant validity and reliability in the Norwegian context. The present study is a cross-sectional multi-centre study. After a pilot test, the Norwegian version of the RAS-R was distributed to 231 service users in mental health specialist and community services. The factor structure of the instrument was investigated by a confirmatory factor analysis (CFA), and internal consistency was assessed by Cronbach's alpha. The RAS-R was found to be acceptable and feasible for service users. The original five-factor structure was confirmed. All model fit indices, including the standardised root mean square residual (SRMR), which is independent of the χ 2 -test, met the criteria for an acceptable model fit. Internal consistencies within sub-scales as measured by Cronbach's alpha ranged from 0.65 to 0.85. Cronbach's alpha for the total scale was 0.90. As expected, some redundancy between factors existed (in particular among the factors Personal confidence and hope, Goal and success orientation and Not dominated by symptoms). The Norwegian RAS-R showed acceptable psychometric properties in terms of convergent validity and reliability, and fit indices from the CFA confirmed the original factor structure. We recommend the Norwegian RAS-R as a tool in service users' and health professionals' collaborative work towards the service users' recovery goals and as an outcome measure in larger evaluations.
Argentzell, Elisabeth; Hultqvist, Jenny; Neil, Sandra; Eklund, Mona
2017-10-01
Personal recovery, defined as an individual process towards meaning, is an important target within mental health services. Measuring recovery hence requires reliable and valid measures. The Process of Recovery Questionnaire (QPR) was developed for that purpose. The aim was to develop a Swedish version of the QPR (QPR-Swe) and explore its psychometric properties in terms of factor structure, internal consistency, construct validity and sensitivity to change. A total of 226 participants entered the study. The factor structure was investigated by Principal Component Analysis and Scree plot. Construct validity was addressed in terms of convergent validity against indicators of self-mastery, self-esteem, quality of life and self-rated health. A one-factor solution of QPR-Swe received better support than a two-factor solution. Good internal consistency was indicated, α = 0.92, and construct validity was satisfactory. The QPR-Swe showed preliminary sensitivity to change. The QPR-Swe showed promising initial psychometric properties in terms of internal consistency, convergent validity and sensitivity to change. The QPR-Swe is recommended for use in research and clinical contexts to assess personal recovery among people with mental illness.
Mills, S D; Azizoddin, D; Racaza, G Z; Wallace, D J; Weisman, M H; Nicassio, P M
2017-10-01
Objective Systemic lupus erythematosus (SLE) is a chronic, multisystem autoimmune disease characterized by periods of remission and recurrent flares, which have been associated with stress. Despite the significance of stress in this disease, the Perceived Stress Scale-10 has yet to be psychometrically evaluated in patients with SLE. Methods Exploratory factor analysis was used to examine the structural validity of the Perceived Stress Scale-10 among patients with SLE ( N = 138) receiving medical care at Cedars Sinai Medical Center. Cronbach's coefficient alpha was used to examine internal consistency reliability, and Pearson product-moment correlations were used to examine convergent validity with measures of anxiety, depression, helplessness, and disease activity. Results Exploratory factor analysis provided support for a two-factor structure (comparative fit index = .95; standardized root mean residual = .04; root mean square error of approximation = .08). Internal consistency reliability was good for both factors (α = .84 and .86). Convergent validity was evidenced via significant correlations with measures of anxiety, depression, and helplessness. There were no significant correlations with the measure of disease activity. Conclusion The Perceived Stress Scale-10 can be used to examine perceived stress among patients with SLE.
NASA Astrophysics Data System (ADS)
Hsieh, Shang Yu; Neubauer, Franz
2015-04-01
The internal structure of major strike-slip faults is still poorly understood, particularly how to extrapolate subsurface structures by surface expressions. Series of brittle analogue experiments by Leever et al., 2011 resulted the convergence angle is the most influential factor for surface structures. Further analogue models with different ductile settings allow a better understanding in extrapolating surface structures to the subsurface geometry of strike-slip faults. Fifteen analogue experiments were constructed to represent strike-slip faults in nature in different geological settings. As key parameters investigated in this study include: (a) the angle of convergence, (b) the thickness of brittle layer, (c) the influence of a rheological weak layer within the crust, and (d) influence of a thick and rheologically weak layer at the base of the crust. The experiments are aimed to explain first order structures along major transcurrent strike-slip faults such as the Altyn, Kunlun, San Andrea and Greendale (Darfield earthquake 2010) faults. The preliminary results show that convergence angle significantly influences the overall geometry of the transpressional system with greater convergence angles resulting in wider fault zones and higher elevation. Different positions, densities and viscosities of weak rheological layers have not only different surface expressions but also affect the fault geometry in the subsurface. For instance, rheological weak material in the bottom layer results in stretching when experiment reaches a certain displacement and a buildup of a less segmented, wide positive flower structure. At the surface, a wide fault valley in the middle of the fault zone is the reflection of stretching along the velocity discontinuity at depth. In models with a thin and rheologically weaker layer in the middle of the brittle layer, deformation is distributed over more faults and the geometry of the fault zone below and above the weak zone shows significant differences, suggesting that the correlation of structures across a weak layer has to be supported by geophysical data, which help constraining the geometry of the deep part. This latter experiment has significantly similar phenomena in reality, such as few pressure ridges along Altyn fault. The experimental results underline the need to understand the role of the convergence angle and the influence of rheology on fault evolution, in order to connect between surface deformation and subsurface geometry.
NASA Astrophysics Data System (ADS)
Hsieh, S. Y.; Neubauer, F.; Willingshofer, E.; Sokoutis, D.
2014-12-01
The internal structure of major strike-slip faults is still poorly understood, particularly how the deep structure could be inferred from its surface expression (Molnar and Dayem, 2011). Previous analogue experiments suggest that the convergence angle is the most influential factor (Leever et al., 2011). Further analogue modeling may allow a better understanding how to extrapolate surface structures to the subsurface geometry of strike-slip faults. Various scenarios of analogue experiments were designed to represent strike-slip faults in nature from different geological settings. As such key parameters, which are investigated in this study include: (a) the angle of convergence, (b) the thickness of brittle layer, (c) the influence of a rheological weak layer within the crust, and (d) influence of a thick and rheologically weak layer at the base of the crust. The latter aimed to simulate the effect of a hot metamorphic core complex or an alignment of uprising plutons bordered by a transtensional/transpressional strike-slip fault. The preliminary results show that convergence angle significantly influences the overall geometry of the transpressive system with greater convergence angles resulting in wider fault zones and higher elevation. Different positions, densities and viscosities of weak rheological layers have not only different surface expressions but also affect the fault geometry in the subsurface. For instance, rheological weak material in the bottom layer results in stretching when experiment reaches a certain displacement and a buildup of a less segmented, wide positive flower structure. At the surface, a wide fault valley in the middle of the fault zone is the reflection of stretching along the velocity discontinuity at depth. In models with a thin and rheologically weaker layer in the middle of the brittle layer, deformation is distributed over more faults and the geometry of the fault zone below and above the weak zone shows significant differences. This latter experiment has significantly similar phenomena in reality, such as few pressure ridges along Altyn fault. The experimental results underline the need to understand the role of the convergence angle and the influence of rheology on fault evolution, in order to connect between surface deformation and subsurface geometry.
Development and validity of a scale to measure workplace culture of health.
Kwon, Youngbum; Marzec, Mary L; Edington, Dee W
2015-05-01
To describe the development of and test the validity and reliability of the Workplace Culture of Health (COH) scale. Exploratory factor analysis and confirmatory factor analysis were performed on data from a health care organization (N = 627). To verify the factor structure, confirmatory factor analysis was performed on a second data set from a medical equipment manufacturer (N = 226). The COH scale included a structure of five orthogonal factors: senior leadership and polices, programs and rewards, quality assurance, supervisor support, and coworker support. With regard to construct validity (convergent and discriminant) and reliability, two different US companies showed the same factorial structure, satisfactory fit statistics, and suitable internal and external consistency. The COH scale represents a reliable and valid scale to assess the workplace environment and culture for supporting health.
Mills, Sarah D; Fox, Rina S; Malcarne, Vanessa L; Roesch, Scott C; Champagne, Brian R; Sadler, Georgia Robins
2014-07-01
The Generalized Anxiety Disorder-7 scale (GAD-7) is a self-report questionnaire that is widely used to screen for anxiety. The GAD-7 has been translated into numerous languages, including Spanish. Previous studies evaluating the structural validity of the English and Spanish versions indicate a unidimensional factor structure in both languages. However, the psychometric properties of the Spanish language version have yet to be evaluated in samples outside of Spain, and the measure has not been tested for use among Hispanic Americans. This study evaluated the reliability, structural validity, and convergent validity of the English and Spanish language versions of the GAD-7 for Hispanic Americans in the United States. A community sample of 436 Hispanic Americans with an English (n = 210) or Spanish (n = 226) language preference completed the GAD-7. Multiple-group confirmatory factor analysis (CFA) was used to examine the goodness-of-fit of the unidimensional factor structure of the GAD-7 across language-preference groups. Results from the multiple-group CFA indicated a similar unidimensional factor structure with equivalent response patterns and item intercepts, but different variances, across language-preference groups. Internal consistency was good for both English and Spanish language-preference groups. The GAD-7 also evidenced good convergent validity as demonstrated by significant correlations in expected directions with the Perceived Stress Scale, the Patient Health Questionnaire-9, and the Physical Health domain of the World Health Organization Quality of Life-BREF assessment. The unidimensional GAD-7 is suitable for use among Hispanic Americans with an English or Spanish language preference.
Multilevel multi-informant structure of the authoritative school climate survey.
Konold, Timothy; Cornell, Dewey; Huang, Francis; Meyer, Patrick; Lacey, Anna; Nekvasil, Erin; Heilbrun, Anna; Shukla, Kathan
2014-09-01
The Authoritative School Climate Survey was designed to provide schools with a brief assessment of 2 key characteristics of school climate--disciplinary structure and student support--that are hypothesized to influence 2 important school climate outcomes--student engagement and prevalence of teasing and bullying in school. The factor structure of these 4 constructs was examined with exploratory and confirmatory factor analyses in a statewide sample of 39,364 students (Grades 7 and 8) attending 423 schools. Notably, the analyses used a multilevel structural approach to model the nesting of students in schools for purposes of evaluating factor structure, demonstrating convergent and concurrent validity and gauging the structural invariance of concurrent validity coefficients across gender. These findings provide schools with a core group of school climate measures guided by authoritative discipline theory. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Convergence, Degeneracy, and Control
ERIC Educational Resources Information Center
Green, David W.; Crinion, Jenny; Price, Cathy J.
2006-01-01
Understanding the neural representation and control of language in normal bilingual speakers provides insights into the factors that constrain the acquisition of another language, insights into the nature of language expertise, and an understanding of the brain as an adaptive system. We illustrate both functional and structural brain changes…
Müller-Engelmann, Meike; Schnyder, Ulrich; Dittmann, Clara; Priebe, Kathlen; Bohus, Martin; Thome, Janine; Fydrich, Thomas; Pfaltz, Monique C; Steil, Regina
2018-05-01
The Clinician-Administered PTSD Scale (CAPS) is a widely used diagnostic interview for posttraumatic stress disorder (PTSD). Following fundamental modifications in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition ( DSM-5), the CAPS had to be revised. This study examined the psychometric properties (internal consistency, interrater reliability, convergent and discriminant validity, and structural validity) of the German version of the CAPS-5 in a trauma-exposed sample ( n = 223 with PTSD; n =51 without PTSD). The results demonstrated high internal consistency (αs = .65-.93) and high interrater reliability (ICCs = .81-.89). With regard to convergent and discriminant validity, we found high correlations between the CAPS severity score and both the Posttraumatic Diagnostic Scale sum score ( r = .87) and the Beck Depression Inventory total score ( r = .72). Regarding the underlying factor structure, the hybrid model demonstrated the best fit, followed by the anhedonia model. However, we encountered some nonpositive estimates for the correlations of the latent variables (factors) for both models. The model with the best fit without methodological problems was the externalizing behaviors model, but the results also supported the DSM-5 model. Overall, the results demonstrate that the German version of the CAPS-5 is a psychometrically sound measure.
Presoto, Cristina D; Wajngarten, Danielle; Domingos, Patrícia A S; Campos, Juliana A D B; Garcia, Patrícia P N S
2018-01-01
The aims of this study were to adapt the Job Factors Questionnaire to the field of dentistry, evaluate its psychometric properties, evaluate dental students' perceptions of work/study risk factors for musculoskeletal disorders, and determine the influence of gender and academic level on those perceptions. All 580 students enrolled in two Brazilian dental schools in 2015 were invited to participate in the study. A three-factor structure (Repetitiveness, Work Posture, and External Factors) was tested through confirmatory factor analysis. Convergent validity was estimated using the average variance extracted (AVE), discriminant validity was based on the correlational analysis of the factors, and reliability was assessed. A causal model was created using structural equation modeling to evaluate the influence of gender and academic level on students' perceptions. A total of 480 students completed the questionnaire for an 83% response rate. The responding students' average age was 21.6 years (SD=2.98), and 74.8% were women. Higher scores were observed on the Work Posture factor items. The refined model presented proper fit to the studied sample. Convergent validity was compromised only for External Factors (AVE=0.47), and discriminant validity was compromised for Work Posture and External Factors (r 2 =0.69). Reliability was adequate. Academic level did not have a significant impact on the factors, but the women students exhibited greater perception. Overall, the adaptation resulted in a useful instrument for assessing perceptions of risk factors for musculoskeletal disorders. Gender was found to significantly influence all three factors, with women showing greater perception of the risk factors.
Ego-resiliency reloaded: a three-component model of general resiliency.
Farkas, Dávid; Orosz, Gábor
2015-01-01
Ego-resiliency (ER) is a capacity that enables individuals to adapt to constantly changing environmental demands. The goal of our research was to identify components of Ego-resiliency, and to test the reliability and the structural and convergent validity of the refined version of the ER11 Ego-resiliency scale. In Study 1 we used a factor analytical approach to assess structural validity and to identify factors of Ego-resiliency. Comparing alternative factor-structures, a hierarchical model was chosen including three factors: Active Engagement with the World (AEW), Repertoire of Problem Solving Strategies (RPSS), and Integrated Performance under Stress (IPS). In Study 2, the convergent and divergent validity of the ER11 scale and its factors and their relationship with resilience were tested. The results suggested that resiliency is a double-faced construct, with one function to keep the personality system stable and intact, and the other function to adjust the personality system in an adaptive way to the dynamically changing environment. The stability function is represented by the RPSS and IPS components of ER. Their relationship pattern is similar to other constructs of resilience, e.g. the Revised Connor-Davidson Resilience Scale (R-CD-RISC). The flexibility function is represented by the unit of RPSS and AEW components. In Study 3 we tested ER11 on a Hungarian online representative sample and integrated the results in a model of general resiliency. This framework allows us to grasp both the stability-focused and the plasticity-focused nature of resiliency.
Ego-Resiliency Reloaded: A Three-Component Model of General Resiliency
Farkas, Dávid; Orosz, Gábor
2015-01-01
Ego-resiliency (ER) is a capacity that enables individuals to adapt to constantly changing environmental demands. The goal of our research was to identify components of Ego-resiliency, and to test the reliability and the structural and convergent validity of the refined version of the ER11 Ego-resiliency scale. In Study 1 we used a factor analytical approach to assess structural validity and to identify factors of Ego-resiliency. Comparing alternative factor-structures, a hierarchical model was chosen including three factors: Active Engagement with the World (AEW), Repertoire of Problem Solving Strategies (RPSS), and Integrated Performance under Stress (IPS). In Study 2, the convergent and divergent validity of the ER11 scale and its factors and their relationship with resilience were tested. The results suggested that resiliency is a double-faced construct, with one function to keep the personality system stable and intact, and the other function to adjust the personality system in an adaptive way to the dynamically changing environment. The stability function is represented by the RPSS and IPS components of ER. Their relationship pattern is similar to other constructs of resilience, e.g. the Revised Connor-Davidson Resilience Scale (R-CD-RISC). The flexibility function is represented by the unit of RPSS and AEW components. In Study 3 we tested ER11 on a Hungarian online representative sample and integrated the results in a model of general resiliency. This framework allows us to grasp both the stability-focused and the plasticity-focused nature of resiliency. PMID:25815881
Adaptive convergence nonuniformity correction algorithm.
Qian, Weixian; Chen, Qian; Bai, Junqi; Gu, Guohua
2011-01-01
Nowadays, convergence and ghosting artifacts are common problems in scene-based nonuniformity correction (NUC) algorithms. In this study, we introduce the idea of space frequency to the scene-based NUC. Then the convergence speed factor is presented, which can adaptively change the convergence speed by a change of the scene dynamic range. In fact, the convergence speed factor role is to decrease the statistical data standard deviation. The nonuniformity space relativity characteristic was summarized by plenty of experimental statistical data. The space relativity characteristic was used to correct the convergence speed factor, which can make it more stable. Finally, real and simulated infrared image sequences were applied to demonstrate the positive effect of our algorithm.
Synthesis and structural study of two new heparin-like hexasaccharides.
Lucas, Ricardo; Angulo, Jesús; Nieto, Pedro M; Martín-Lomas, Manuel
2003-07-07
Two new heparin-like hexasaccharides, 5 and 6, have been synthesised using a convergent block strategy and their solution conformations have been determined by NMR spectroscopy and molecular modelling. Both hexasaccharides contain the basic structural motif of the regular region of heparin but with negative charge distributions which have been designed to get insight into the mechanism of fibroblast growth factors (FGFs) activation.
The Multidimensional Loss Scale: validating a cross-cultural instrument for measuring loss.
Vromans, Lyn; Schweitzer, Robert D; Brough, Mark
2012-04-01
The Multidimensional Loss Scale (MLS) represents the first instrument designed specifically to index Experience of Loss Events and Loss Distress across multiple domains (cultural, social, material, and intrapersonal) relevant to refugee settlement. Recently settled Burmese adult refugees (N = 70) completed a questionnaire battery, including MLS items. Analyses explored MLS internal consistency, convergent and divergent validity, and factor structure. Cronbach alphas indicated satisfactory internal consistency for Experience of Loss Events (0.85) and Loss Distress (0.92), reflecting a unitary construct of multidimensional loss. Loss Distress did not correlate with depression or anxiety symptoms and correlated moderately with interpersonal grief and trauma symptoms, supporting divergent and convergent validity. Factor analysis provided preliminary support for a five-factor model: Loss of Symbolic Self, Loss of Interdependence, Loss of Home, Interpersonal Loss, and Loss of Intrapersonal Integrity. Received well by participants, the new scale shows promise for application in future research and practice.
The self-description inventory+, part 1 : factor structure and convergent validity analyses.
DOT National Transportation Integrated Search
2013-07-01
Each year the FAA hires approximately 900 new air traffic controller candidates, the majority of whom take the Air Traffic Selection and Training test battery, better known as AT-SAT. This test, developed in 1997, is based on a job/task analysis cond...
NASA Astrophysics Data System (ADS)
Vanrolleghem, Peter A.; Mannina, Giorgio; Cosenza, Alida; Neumann, Marc B.
2015-03-01
Sensitivity analysis represents an important step in improving the understanding and use of environmental models. Indeed, by means of global sensitivity analysis (GSA), modellers may identify both important (factor prioritisation) and non-influential (factor fixing) model factors. No general rule has yet been defined for verifying the convergence of the GSA methods. In order to fill this gap this paper presents a convergence analysis of three widely used GSA methods (SRC, Extended FAST and Morris screening) for an urban drainage stormwater quality-quantity model. After the convergence was achieved the results of each method were compared. In particular, a discussion on peculiarities, applicability, and reliability of the three methods is presented. Moreover, a graphical Venn diagram based classification scheme and a precise terminology for better identifying important, interacting and non-influential factors for each method is proposed. In terms of convergence, it was shown that sensitivity indices related to factors of the quantity model achieve convergence faster. Results for the Morris screening method deviated considerably from the other methods. Factors related to the quality model require a much higher number of simulations than the number suggested in literature for achieving convergence with this method. In fact, the results have shown that the term "screening" is improperly used as the method may exclude important factors from further analysis. Moreover, for the presented application the convergence analysis shows more stable sensitivity coefficients for the Extended-FAST method compared to SRC and Morris screening. Substantial agreement in terms of factor fixing was found between the Morris screening and Extended FAST methods. In general, the water quality related factors exhibited more important interactions than factors related to water quantity. Furthermore, in contrast to water quantity model outputs, water quality model outputs were found to be characterised by high non-linearity.
Validation of the Short Form of the Academic Procrastination Scale.
Yockey, Ronald D
2016-02-01
The factor structure, internal consistency reliability, and convergent validity of the five-item Academic Procrastination Scale-Short Form was investigated on an ethnically diverse sample of college students. The results provided support for the Academic Procrastination Scale-Short Form as a unidimensional measure of academic procrastination, which possessed good internal consistency reliability in this sample of 282 students. The scale also demonstrated good convergent validity, with moderate to large correlations with both the Procrastination Assessment Scale-Students and the Tuckman Procrastination Scale. Implications of the results are discussed and recommendations for future work provided.
Convergent evolution of gene networks by single-gene duplications in higher eukaryotes.
Amoutzias, Gregory D; Robertson, David L; Oliver, Stephen G; Bornberg-Bauer, Erich
2004-03-01
By combining phylogenetic, proteomic and structural information, we have elucidated the evolutionary driving forces for the gene-regulatory interaction networks of basic helix-loop-helix transcription factors. We infer that recurrent events of single-gene duplication and domain rearrangement repeatedly gave rise to distinct networks with almost identical hub-based topologies, and multiple activators and repressors. We thus provide the first empirical evidence for scale-free protein networks emerging through single-gene duplications, the dominant importance of molecular modularity in the bottom-up construction of complex biological entities, and the convergent evolution of networks.
Aarons, Gregory A; Ehrhart, Mark G; Farahnak, Lauren R
2014-04-14
In healthcare and allied healthcare settings, leadership that supports effective implementation of evidenced-based practices (EBPs) is a critical concern. However, there are no empirically validated measures to assess implementation leadership. This paper describes the development, factor structure, and initial reliability and convergent and discriminant validity of a very brief measure of implementation leadership: the Implementation Leadership Scale (ILS). Participants were 459 mental health clinicians working in 93 different outpatient mental health programs in Southern California, USA. Initial item development was supported as part of a two United States National Institutes of Health (NIH) studies focused on developing implementation leadership training and implementation measure development. Clinician work group/team-level data were randomly assigned to be utilized for an exploratory factor analysis (n = 229; k = 46 teams) or for a confirmatory factor analysis (n = 230; k = 47 teams). The confirmatory factor analysis controlled for the multilevel, nested data structure. Reliability and validity analyses were then conducted with the full sample. The exploratory factor analysis resulted in a 12-item scale with four subscales representing proactive leadership, knowledgeable leadership, supportive leadership, and perseverant leadership. Confirmatory factor analysis supported an a priori higher order factor structure with subscales contributing to a single higher order implementation leadership factor. The scale demonstrated excellent internal consistency reliability as well as convergent and discriminant validity. The ILS is a brief and efficient measure of unit level leadership for EBP implementation. The availability of the ILS will allow researchers to assess strategic leadership for implementation in order to advance understanding of leadership as a predictor of organizational context for implementation. The ILS also holds promise as a tool for leader and organizational development to improve EBP implementation.
2014-01-01
Background In healthcare and allied healthcare settings, leadership that supports effective implementation of evidenced-based practices (EBPs) is a critical concern. However, there are no empirically validated measures to assess implementation leadership. This paper describes the development, factor structure, and initial reliability and convergent and discriminant validity of a very brief measure of implementation leadership: the Implementation Leadership Scale (ILS). Methods Participants were 459 mental health clinicians working in 93 different outpatient mental health programs in Southern California, USA. Initial item development was supported as part of a two United States National Institutes of Health (NIH) studies focused on developing implementation leadership training and implementation measure development. Clinician work group/team-level data were randomly assigned to be utilized for an exploratory factor analysis (n = 229; k = 46 teams) or for a confirmatory factor analysis (n = 230; k = 47 teams). The confirmatory factor analysis controlled for the multilevel, nested data structure. Reliability and validity analyses were then conducted with the full sample. Results The exploratory factor analysis resulted in a 12-item scale with four subscales representing proactive leadership, knowledgeable leadership, supportive leadership, and perseverant leadership. Confirmatory factor analysis supported an a priori higher order factor structure with subscales contributing to a single higher order implementation leadership factor. The scale demonstrated excellent internal consistency reliability as well as convergent and discriminant validity. Conclusions The ILS is a brief and efficient measure of unit level leadership for EBP implementation. The availability of the ILS will allow researchers to assess strategic leadership for implementation in order to advance understanding of leadership as a predictor of organizational context for implementation. The ILS also holds promise as a tool for leader and organizational development to improve EBP implementation. PMID:24731295
Validation of the Personal Need for Structure Scale in Chinese.
Shi, Junqi; Wang, Lei; Chen, Yang
2009-08-01
To validate the Chinese version of the Personal Need for Structure Scale, questionnaires were administered to 1,418 individuals in three samples. Item-total correlations and internal consistency of the scale were acceptable. The test-retest reliability was .79. Confirmatory factor analysis indicated that the Chinese version comprised two dimensions, as did the original version; Desire for Structure and Response to Lack of Structure. Correlation coefficients between the Personal Need for Structure Scale and other related measures indicated that the scale has acceptable discriminant validity and convergent validity.
Orbit orientation in didelphid marsupials (Didelphimorphia: Didelphidae)
Pilatti, Patricia
2017-01-01
Abstract Usually considered a morphologically conservative group, didelphid marsupials present considerable variation in ecology and body size, some of which were shown to relate to morphological structures. Thus, changes on orbit morphology are likely and could be related to that variation. We calculated orbit orientation in 873 specimens of 16 Didelphidae genera yielding estimates of orbits convergence (their position relative to midsagittal line) and verticality (their position relative to frontal plane). We then compared similarities in these variables across taxa to ecological, morphological and phylogenetic data to evaluate the influencing factors on orbit orientation in didelphids. We found an inverse relation between convergence and verticality. Didelphids orbits have low verticality but are highly convergent, yet orbit orientation differs significantly between taxa, and that variation is related to morphological aspects of the cranium. Rostral variables are the only morphological features correlated with orbit orientation: increasing snout length yields more convergent orbits, whereas increase on snout breadth imply in more vertical orbits. Size and encephalization quotients are uncorrelated with orbit orientation. Among ecological data, diet showed significant correlation whereas locomotion is the factor that less affects the position of orbits. Phylogeny is uncorrelated to any orbital parameters measured. Ecological factors seemingly play a more important role on orbit orientation than previously expected, and differentiation on orbit orientation seems to be more functional than inherited. Thus, despite the apparent homogeneity on didelphid morphology, there is subtle morphological variability that may be directly related to feeding behavior. PMID:29492000
Measuring Long-Distance Romantic Relationships: A Validity Study
ERIC Educational Resources Information Center
Pistole, M. Carole; Roberts, Amber
2011-01-01
This study investigated aspects of construct validity for the scores of a new long-distance romantic relationship measure. A single-factor structure of the long-distance romantic relationship index emerged, with convergent and discriminant evidence of external validity, high internal consistency reliability, and applied utility of the scores.…
Teacher Competencies through the Prism of Educational Research
ERIC Educational Resources Information Center
Peklaj, Cirila
2015-01-01
The present article focuses on teacher competencies as a major factor that impacts student learning. Ultimately, all attempts to improve education converge in the teacher and the quality of his/her work with students. With their teaching methods, their communication and their classroom management, teachers can structure the kind of learning…
Psychometric properties of the Body Checking Questionnaire in college women.
White, Emily K; Claudat, Kim; Jones, Sarah C; Barchard, Kimberly A; Warren, Cortney S
2015-03-01
While the Body Checking Questionnaire (BCQ; Reas et al., 2002) is the most commonly-used measure of body checking behaviors, findings on the factor structure in nonclinical samples are mixed. This study investigated the factor structure and psychometric properties of the BCQ among nonclinical college women. In Study 1 (n=326), an exploratory factor analysis indicated factors corresponding to (a) behavioral and (b) visual checking. In Study 2 (n=1013), a confirmatory factor analysis revealed adequate fit for these factors, better than the original or total score solutions. Scales based upon the two factors demonstrated good internal consistency, convergent validity with measures of eating pathology, and sensitivity for detecting at-risk eating pathology. Results suggest an alternate two-factor solution that differs from the original three-factor solution. Copyright © 2015. Published by Elsevier Ltd.
Mills, Sarah D.; Fox, Rina S.; Malcarne, Vanessa L.; Roesch, Scott C.; Champagne, Brian R.; Sadler, Georgia Robins
2014-01-01
The Generalized Anxiety Disorder-7 scale (GAD-7) is a self-report questionnaire that is widely used to screen for anxiety. The GAD-7 has been translated into numerous languages, including Spanish. Previous studies evaluating the structural validity of the English and Spanish versions indicate a uni-dimensional factor structure in both languages. However, the psychometric properties of the Spanish language version have yet to be evaluated in samples outside of Spain, and the measure has not been tested for use among Hispanic Americans. This study evaluated the reliability, structural validity, and convergent validity of the English and Spanish language versions of the GAD-7 for Hispanic Americans in the United States. A community sample of 436 Hispanic Americans with an English (n = 210) or Spanish (n = 226) language preference completed the GAD-7. Multiple-group confirmatory factor analysis (CFA) was used to examine the goodness of fit of the uni-dimensional factor structure of the GAD-7 across language-preference groups. Results from the multiple-group CFA indicated a similar unidimensional factor structure with equivalent response patterns and item intercepts, but different variances, across language-preference groups. Internal consistency was good for both English and Spanish language-preference groups. The GAD-7 also evidenced good convergent validity as demonstrated by significant correlations in expected directions with the Perceived Stress Scale, the Patient Health Questionnaire-9, and the Physical health domain of the World Health Organization Quality of Life-BREF assessment. The uni-dimensional GAD-7 is suitable for use among Hispanic Americans with an English or Spanish language preference. PMID:25045957
Kondo, Masaki; Kiyomizu, Kensuke; Goto, Fumiyuki; Kitahara, Tadashi; Imai, Takao; Hashimoto, Makoto; Shimogori, Hiroaki; Ikezono, Tetsuo; Nakayama, Meiho; Watanabe, Norio; Akechi, Tatsuo
2015-01-22
Dizziness or vertigo is associated with both vestibular-balance and psychological factors. A common assessment tool is the Vertigo Symptom Scale (VSS) -short form, which has two subscales: vestibular-balance and autonomic-anxiety. Despite frequent use, the factor structure of the VSS-short form has yet to be confirmed. Here, we clarified the factor structure of the VSS-short form, and assessed the validity and reliability of the Japanese version of this tool. We conducted a cross-sectional, multicenter, psychometric evaluation of patients with non-central dizziness or vertigo persisting for longer than 1 month. Participants completed the VSS-short form, the Dizziness Handicap Inventory, and the Hospital Anxiety and Depression Scale. They also completed the VSS-short form a second time 1-3 days later. The questionnaire was translated into Japanese and cross-culturally adapted. We conducted a confirmatory factor analysis followed by an exploratory factor analysis. Convergent and discriminant validity, internal consistency, and test-retest reliability were evaluated. The total sample and retest sample consisted of 159 and 79 participants, respectively. Model-fitting for a two-subscale structure in a confirmatory factor analysis was poor. An exploratory factor analysis produced a three-factor structure: long-duration vestibular-balance symptoms, short-duration vestibular-balance symptoms, and autonomic-anxiety symptoms. Regarding convergent and discriminant validity, all hypotheses were clearly supported. We obtained high Cronbach's α coefficients for the total score and subscales, ranging from 0.758 to 0.866. Total score and subscale interclass correlation coefficients for test-retest reliability were acceptable, ranging from 0.867 to 0.897. The VSS-short form has a three-factor structure that was cross-culturally well-matched with previous data from the VSS-long version. Thus, it was suggested that vestibular-balance symptoms can be analyzed separately according to symptom duration, which may reflect pathophysiological factors. The VSS-short form can be used to evaluate vestibular-balance symptoms and autonomic-anxiety symptoms, as well as the duration of vestibular-balance symptoms. Further research using the VSS-short form should be required in other languages and populations.
Achieving accuracy in first-principles calculations for EOS: basis completeness at high temperatures
NASA Astrophysics Data System (ADS)
Wills, John; Mattsson, Ann
2013-06-01
First-principles electronic structure calculations can provide EOS data in regimes of pressure and temperature where accurate experimental data is difficult or impossible to obtain. This lack, however, also precludes validation of calculations in those regimes. Factors that influence the accuracy of first-principles data include (1) theoretical approximations and (2) computational approximations used in implementing and solving the underlying equations. In the first category are the approximate exchange/correlation functionals and approximate wave equations approximating the Dirac equation; in the second are basis completeness, series convergence, and truncation errors. We are using two rather different electronic structure methods (VASP and RSPt) to make definitive the requirements for accuracy of the second type, common to both. In this talk, we discuss requirements for converged calculation at high temperature and moderated pressure. At convergence we show that both methods give identical results. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Ang, Rebecca P; Lowe, Patricia A; Yusof, Noradlin
2011-12-01
The present study investigated the factor structure, reliability, convergent and discriminant validity, and U.S. norms of the Revised Children's Manifest Anxiety Scale, Second Edition (RCMAS-2; C. R. Reynolds & B. O. Richmond, 2008a) scores in a Singapore sample of 1,618 school-age children and adolescents. Although there were small statistically significant differences in the average RCMAS-2 T scores found across various demographic groupings, on the whole, the U.S. norms appear adequate for use in the Asian Singapore sample. Results from item bias analyses suggested that biased items detected had small effects and were counterbalanced across gender and ethnicity, and hence, their relative impact on test score variation appears to be minimal. Results of factor analyses on the RCMAS-2 scores supported the presence of a large general anxiety factor, the Total Anxiety factor, and the 5-factor structure found in U.S. samples was replicated. Both the large general anxiety factor and the 5-factor solution were invariant across gender and ethnic background. Internal consistency estimates ranged from adequate to good, and 2-week test-retest reliability estimates were comparable to previous studies. Evidence providing support for convergent and discriminant validity of the RCMAS-2 scores was also found. Taken together, findings provide additional cross-cultural evidence of the appropriateness and usefulness of the RCMAS-2 as a measure of anxiety in Asian Singaporean school-age children and adolescents.
The Skin Picking Impact Scale: Factor structure, validity and development of a short version.
Snorrason, Ivar; Olafsson, Ragnar P; Flessner, Christopher A; Keuthen, Nancy J; Franklin, Martin E; Woods, Douglas W
2013-08-01
In the present study, we examined the psychometric properties of the Skin Picking Impact Scale (SPIS; Keuthen, Deckersbach, Wilhelm et al., 2001), a 10 item self-report questionnaire designed to assess the psychosocial impact of skin picking disorder (SPD). Participants were 650 individuals who met criteria for SPD in an online survey. Exploratory and confirmatory factor analyses demonstrated a unitary factor structure with high internal consistency (α = 0.94). Consequently, we constructed an abbreviated 4-item version that retained good internal consistency (α = 0.87) and a robust factor structure. Both the short and the full versions demonstrated discriminant and convergent/concurrent validity. In conclusion, the findings indicate that both versions are psychometrically sound measures of SPD related psychosocial impact; however, some potential limitations of the full scale are discussed. © 2013 The Scandinavian Psychological Associations.
Development and validation of the Alcohol Myopia Scale.
Lac, Andrew; Berger, Dale E
2013-09-01
Alcohol myopia theory conceptualizes the ability of alcohol to narrow attention and how this demand on mental resources produces the impairments of self-inflation, relief, and excess. The current research was designed to develop and validate a scale based on this framework. People who were alcohol users rated items representing myopic experiences arising from drinking episodes in the past month. In Study 1 (N = 260), the preliminary 3-factor structure was supported by exploratory factor analysis. In Study 2 (N = 289), the 3-factor structure was substantiated with confirmatory factor analysis, and it was superior in fit to an empirically indefensible 1-factor structure. The final 14-item scale was evaluated with internal consistency reliability, discriminant validity, convergent validity, criterion validity, and incremental validity. The alcohol myopia scale (AMS) illuminates conceptual underpinnings of this theory and yields insights for understanding the tunnel vision that arises from intoxication.
The (mis)measurement of the Dark Triad Dirty Dozen: exploitation at the core of the scale
Kajonius, Petri J.; Persson, Björn N.; Rosenberg, Patricia
2016-01-01
Background. The dark side of human character has been conceptualized in the Dark Triad Model: Machiavellianism, psychopathy, and narcissism. These three dark traits are often measured using single long instruments for each one of the traits. Nevertheless, there is a necessity of short and valid personality measures in psychological research. As an independent research group, we replicated the factor structure, convergent validity and item response for one of the most recent and widely used short measures to operationalize these malevolent traits, namely, Jonason’s Dark Triad Dirty Dozen. We aimed to expand the understanding of what the Dirty Dozen really captures because the mixed results on construct validity in previous research. Method. We used the largest sample to date to respond to the Dirty Dozen (N = 3,698). We firstly investigated the factor structure using Confirmatory Factor Analysis and an exploratory distribution analysis of the items in the Dirty Dozen. Secondly, using a sub-sample (n = 500) and correlation analyses, we investigated the Dirty Dozen dark traits convergent validity to Machiavellianism measured by the Mach-IV, psychopathy measured by Eysenck’s Personality Questionnaire Revised, narcissism using the Narcissism Personality Inventory, and both neuroticism and extraversion from the Eysenck’s questionnaire. Finally, besides these Classic Test Theory analyses, we analyzed the responses for each Dirty Dozen item using Item Response Theory (IRT). Results. The results confirmed previous findings of a bi-factor model fit: one latent core dark trait and three dark traits. All three Dirty Dozen traits had a striking bi-modal distribution, which might indicate unconcealed social undesirability with the items. The three Dirty Dozen traits did converge too, although not strongly, with the contiguous single Dark Triad scales (r between .41 and .49). The probabilities of filling out steps on the Dirty Dozen narcissism-items were much higher than on the Dirty Dozen items for Machiavellianism and psychopathy. Overall, the Dirty Dozen instrument delivered the most predictive value with persons with average and high Dark Triad traits (theta > −0.5). Moreover, the Dirty Dozen scale was better conceptualized as a combined Machiavellianism-psychopathy factor, not narcissism, and is well captured with item 4: ‘I tend to exploit others towards my own end.’ Conclusion. The Dirty Dozen showed a consistent factor structure, a relatively convergent validity similar to that found in earlier studies. Narcissism measured using the Dirty Dozen, however, did not contribute with information to the core of the Dirty Dozen construct. More importantly, the results imply that the core of the Dirty Dozen scale, a manipulative and anti-social trait, can be measured by a Single Item Dirty Dark Dyad (SIDDD). PMID:26966673
The (mis)measurement of the Dark Triad Dirty Dozen: exploitation at the core of the scale.
Kajonius, Petri J; Persson, Björn N; Rosenberg, Patricia; Garcia, Danilo
2016-01-01
Background. The dark side of human character has been conceptualized in the Dark Triad Model: Machiavellianism, psychopathy, and narcissism. These three dark traits are often measured using single long instruments for each one of the traits. Nevertheless, there is a necessity of short and valid personality measures in psychological research. As an independent research group, we replicated the factor structure, convergent validity and item response for one of the most recent and widely used short measures to operationalize these malevolent traits, namely, Jonason's Dark Triad Dirty Dozen. We aimed to expand the understanding of what the Dirty Dozen really captures because the mixed results on construct validity in previous research. Method. We used the largest sample to date to respond to the Dirty Dozen (N = 3,698). We firstly investigated the factor structure using Confirmatory Factor Analysis and an exploratory distribution analysis of the items in the Dirty Dozen. Secondly, using a sub-sample (n = 500) and correlation analyses, we investigated the Dirty Dozen dark traits convergent validity to Machiavellianism measured by the Mach-IV, psychopathy measured by Eysenck's Personality Questionnaire Revised, narcissism using the Narcissism Personality Inventory, and both neuroticism and extraversion from the Eysenck's questionnaire. Finally, besides these Classic Test Theory analyses, we analyzed the responses for each Dirty Dozen item using Item Response Theory (IRT). Results. The results confirmed previous findings of a bi-factor model fit: one latent core dark trait and three dark traits. All three Dirty Dozen traits had a striking bi-modal distribution, which might indicate unconcealed social undesirability with the items. The three Dirty Dozen traits did converge too, although not strongly, with the contiguous single Dark Triad scales (r between .41 and .49). The probabilities of filling out steps on the Dirty Dozen narcissism-items were much higher than on the Dirty Dozen items for Machiavellianism and psychopathy. Overall, the Dirty Dozen instrument delivered the most predictive value with persons with average and high Dark Triad traits (theta > -0.5). Moreover, the Dirty Dozen scale was better conceptualized as a combined Machiavellianism-psychopathy factor, not narcissism, and is well captured with item 4: 'I tend to exploit others towards my own end.' Conclusion. The Dirty Dozen showed a consistent factor structure, a relatively convergent validity similar to that found in earlier studies. Narcissism measured using the Dirty Dozen, however, did not contribute with information to the core of the Dirty Dozen construct. More importantly, the results imply that the core of the Dirty Dozen scale, a manipulative and anti-social trait, can be measured by a Single Item Dirty Dark Dyad (SIDDD).
NASA Technical Reports Server (NTRS)
Milman, Mark H.
1987-01-01
The fundamental control synthesis issue of establishing a priori convergence rates of approximation schemes for feedback controllers for a class of distributed parameter systems is addressed within the context of hereditary systems. Specifically, a factorization approach is presented for deriving approximations to the optimal feedback gains for the linear regulator-quadratic cost problem associated with time-varying functional differential equations with control delays. The approach is based on a discretization of the state penalty which leads to a simple structure for the feedback control law. General properties of the Volterra factors of Hilbert-Schmidt operators are then used to obtain convergence results for the controls, trajectories and feedback kernels. Two algorithms are derived from the basic approximation scheme, including a fast algorithm, in the time-invariant case. A numerical example is also considered.
NASA Technical Reports Server (NTRS)
Milman, Mark H.
1988-01-01
The fundamental control synthesis issue of establishing a priori convergence rates of approximation schemes for feedback controllers for a class of distributed parameter systems is addressed within the context of hereditary schemes. Specifically, a factorization approach is presented for deriving approximations to the optimal feedback gains for the linear regulator-quadratic cost problem associated with time-varying functional differential equations with control delays. The approach is based on a discretization of the state penalty which leads to a simple structure for the feedback control law. General properties of the Volterra factors of Hilbert-Schmidt operators are then used to obtain convergence results for the controls, trajectories and feedback kernels. Two algorithms are derived from the basic approximation scheme, including a fast algorithm, in the time-invariant case. A numerical example is also considered.
Chau, Janita P C; Thompson, David R; Chang, Anne M; Woo, Jean
2012-11-01
To establish the psychometric properties of the Chinese version of the State Self-Esteem Scale in stroke patients. Self-esteem is seen to enhance peoples' ability to cope with disease: low self-esteem may inhibit participation in rehabilitation and thus result in poor health and social outcomes. Although the Chinese version of the State Self-Esteem Scale has been used as an outcome measure for stroke rehabilitation, no study has examined its factor structure in this patient group. A cross-sectional design. A convenience sample of 265 Chinese stroke patients (mean age 71·4, SD 10·3 years), with a minimum score of 18 out of a possible 30 for the Mini Mental State Exam recruited from two regional rehabilitation hospitals in Hong Kong. An exploratory factor analysis and an internal consistency analysis of the State Self-Esteem Scale were conducted. Pearson's correlation coefficients were calculated between the State Self-Esteem Scale and the Geriatric Depression Scale to determine convergent validity. The final factor solution comprised a three-factor model with correlated constructs and accounted for 49·5% of the total variance. Significant negative correlations were found between the Geriatric Depression Scale and the State Self-Esteem Scale subscale scores (r-0·31 to -0·55, p < 0·01), indicating that the State Self-Esteem Scale had acceptable convergent validity. The new three-factor structure had higher Cronbach's alphas when compared with the original three-factor structure. The State Self-Esteem Scale appears to be a useful measure for assessing state self-esteem in stroke patients. To establish the concurrent, discriminative and construct validities, the factor structure of the SSES could be further developed and tested. © 2011 Blackwell Publishing Ltd.
ERIC Educational Resources Information Center
Laurenceau, Jean-Philippe; Kleinman, Brighid M.; Kaczynski, Karen J.; Carver, Charles S.
2010-01-01
Self-report scales assessing relationship-specific incentive and threat sensitivity were created. Initial tests of factor structure and associations with relationship quality were conducted in a sample of persons in intimate relationships (Study 1). Associations with conceptually related measures were examined to determine convergent and…
Meta-Analysis of the English Version of the Beck Depression Inventory-Second Edition
ERIC Educational Resources Information Center
Erford, Bradley T.; Johnson, Erin; Bardoshi, Gerta
2016-01-01
This meta-analysis reviewed 144 studies from 1996 to 2013 using the Beck Depression Inventory-Second Edition. Internal consistency was 0.89 and test-retest reliability 0.75. Convergent comparisons were robust across 43 depression instruments. Structural validity supported both one- and two-factor solutions and diagnostic accuracy varied according…
ERIC Educational Resources Information Center
Matte, Melody; Lafontaine, Marie-France
2012-01-01
The objective of the present study was to provide validity evidence for the scores from the Romantic Relationship Perfectionism Scale. Results indicate a two-factor structure, adequate reliability, and overall good convergent, concurrent, discriminant, and incremental validity evidence. The strengths and limitations of this measure are discussed.…
Development and Initial Validation of the Counseling Center Assessment of Psychological Symptoms-34
ERIC Educational Resources Information Center
Locke, Benjamin D.; McAleavey, Andrew A.; Zhao, Yu; Lei, Pui-Wa; Hayes, Jeffrey A.; Castonguay, Louis G.; Li, Hongli; Tate, Robin; Lin, Yu-Chu
2012-01-01
A short version of the Counseling Center Assessment of Psychological Symptoms-62 (CCAPS-62) was created via three studies. The final short version (CCAPS-34), which contains 34 items and 7 subscales, demonstrated good discrimination power, support for the proposed factor structure, strong initial convergent validity, and adequate test-retest…
The Utility of the Family Empowerment Scale With Custodial Grandmothers
Hayslip, Bert; Smith, Gregory C.; Montoro-Rodriguez, Julian; Streider, Frederick H.; Merchant, William
2016-01-01
The Family Empowerment Scale (FES) was developed specifically to assess empowerment in families with emotional disorders. Its relevance to custodial grandfamilies is reflected in the difficulties in grandchildren's social, emotional, and behavioral functioning, wherein such difficulties may be explained via either reactions to changes in their family structure or in their responses to the newly formed family unit. Utilizing 27 items derived from the 34-item version of the FES, which had represented differential levels of empowerment (family, service system, community) as indexed by one's attitudes, knowledge, and behavior, we explored the factor structure, internal consistency, construct, and convergent validity of the FES with grandparent caregivers. Three-hundred forty-three (M age = 58.45, SD = 8.22, n Caucasian = 152, n African American = 149, n Hispanic = 38) custodial grandmothers caring for grandchildren between ages 4 and 12 years completed the 27 FES items and various measures of their psychological well-being, grandchild psychological difficulties, emotional support, and parenting practices. Factor analysis revealed three factors that differed slightly from the originally proposed FES subscales: Parental Self-Efficacy/Self-Confidence, Service Activism, and Service Knowledge. Each of the factors was internally consistent, and derived factor scores were moderately interrelated, speaking to the question of convergent validity. The construct validity of these three factors was evidenced by meaningful patterns of statistically significant correlations with grandmothers’ psychological well-being, grandchild psychological difficulties, emotional support, and parenting practices. These factor scores were independent of grandmother age, health, and education. These findings suggest the newly identified FES factors to be valuable in understanding empowerment among grandmother caregivers. PMID:26452627
The Utility of the Family Empowerment Scale With Custodial Grandmothers.
Hayslip, Bert; Smith, Gregory C; Montoro-Rodriguez, Julian; Streider, Frederick H; Merchant, William
2017-03-01
The Family Empowerment Scale (FES) was developed specifically to assess empowerment in families with emotional disorders. Its relevance to custodial grandfamilies is reflected in the difficulties in grandchildren's social, emotional, and behavioral functioning, wherein such difficulties may be explained via either reactions to changes in their family structure or in their responses to the newly formed family unit. Utilizing 27 items derived from the 34-item version of the FES, which had represented differential levels of empowerment (family, service system, community) as indexed by one's attitudes, knowledge, and behavior, we explored the factor structure, internal consistency, construct, and convergent validity of the FES with grandparent caregivers. Three-hundred forty-three ( M age = 58.45, SD = 8.22, n Caucasian = 152, n African American = 149, n Hispanic = 38) custodial grandmothers caring for grandchildren between ages 4 and 12 years completed the 27 FES items and various measures of their psychological well-being, grandchild psychological difficulties, emotional support, and parenting practices. Factor analysis revealed three factors that differed slightly from the originally proposed FES subscales: Parental Self-Efficacy/Self-Confidence, Service Activism, and Service Knowledge. Each of the factors was internally consistent, and derived factor scores were moderately interrelated, speaking to the question of convergent validity. The construct validity of these three factors was evidenced by meaningful patterns of statistically significant correlations with grandmothers' psychological well-being, grandchild psychological difficulties, emotional support, and parenting practices. These factor scores were independent of grandmother age, health, and education. These findings suggest the newly identified FES factors to be valuable in understanding empowerment among grandmother caregivers.
Ocean convergence and the dispersion of flotsam.
D'Asaro, Eric A; Shcherbina, Andrey Y; Klymak, Jody M; Molemaker, Jeroen; Novelli, Guillaume; Guigand, Cédric M; Haza, Angelique C; Haus, Brian K; Ryan, Edward H; Jacobs, Gregg A; Huntley, Helga S; Laxague, Nathan J M; Chen, Shuyi; Judt, Falco; McWilliams, James C; Barkan, Roy; Kirwan, A D; Poje, Andrew C; Özgökmen, Tamay M
2018-02-06
Floating oil, plastics, and marine organisms are continually redistributed by ocean surface currents. Prediction of their resulting distribution on the surface is a fundamental, long-standing, and practically important problem. The dominant paradigm is dispersion within the dynamical context of a nondivergent flow: objects initially close together will on average spread apart but the area of surface patches of material does not change. Although this paradigm is likely valid at mesoscales, larger than 100 km in horizontal scale, recent theoretical studies of submesoscales (less than ∼10 km) predict strong surface convergences and downwelling associated with horizontal density fronts and cyclonic vortices. Here we show that such structures can dramatically concentrate floating material. More than half of an array of ∼200 surface drifters covering ∼20 × 20 km 2 converged into a 60 × 60 m region within a week, a factor of more than 10 5 decrease in area, before slowly dispersing. As predicted, the convergence occurred at density fronts and with cyclonic vorticity. A zipperlike structure may play an important role. Cyclonic vorticity and vertical velocity reached 0.001 s -1 and 0.01 ms -1 , respectively, which is much larger than usually inferred. This suggests a paradigm in which nearby objects form submesoscale clusters, and these clusters then spread apart. Together, these effects set both the overall extent and the finescale texture of a patch of floating material. Material concentrated at submesoscale convergences can create unique communities of organisms, amplify impacts of toxic material, and create opportunities to more efficiently recover such material. Copyright © 2018 the Author(s). Published by PNAS.
Ocean convergence and the dispersion of flotsam
Shcherbina, Andrey Y.; Klymak, Jody M.; Molemaker, Jeroen; Guigand, Cédric M.; Haza, Angelique C.; Haus, Brian K.; Ryan, Edward H.; Jacobs, Gregg A.; Huntley, Helga S.; Chen, Shuyi; McWilliams, James C.; Barkan, Roy; Kirwan, A. D.; Poje, Andrew C.; Özgökmen, Tamay M.
2018-01-01
Floating oil, plastics, and marine organisms are continually redistributed by ocean surface currents. Prediction of their resulting distribution on the surface is a fundamental, long-standing, and practically important problem. The dominant paradigm is dispersion within the dynamical context of a nondivergent flow: objects initially close together will on average spread apart but the area of surface patches of material does not change. Although this paradigm is likely valid at mesoscales, larger than 100 km in horizontal scale, recent theoretical studies of submesoscales (less than ∼10 km) predict strong surface convergences and downwelling associated with horizontal density fronts and cyclonic vortices. Here we show that such structures can dramatically concentrate floating material. More than half of an array of ∼200 surface drifters covering ∼20 × 20 km2 converged into a 60 × 60 m region within a week, a factor of more than 105 decrease in area, before slowly dispersing. As predicted, the convergence occurred at density fronts and with cyclonic vorticity. A zipperlike structure may play an important role. Cyclonic vorticity and vertical velocity reached 0.001 s−1 and 0.01 ms−1, respectively, which is much larger than usually inferred. This suggests a paradigm in which nearby objects form submesoscale clusters, and these clusters then spread apart. Together, these effects set both the overall extent and the finescale texture of a patch of floating material. Material concentrated at submesoscale convergences can create unique communities of organisms, amplify impacts of toxic material, and create opportunities to more efficiently recover such material. PMID:29339497
Back to the Consideration of Future Consequences Scale: time to reconsider?
Rappange, David R; Brouwer, Werner B F; van Exel, N Job A
2009-10-01
The Consideration of Future Consequences (CFC) Scale is a measure of the extent to which individuals consider and are influenced by the distant outcomes of current behavior. In this study, the authors conducted factor analysis to investigate the factor structure of the 12-item CFC Scale. The authors found evidence for a multiple factor solution including one completely present-oriented factor consisting of all 7 present-oriented items, and one or two future-oriented factors consisting of the remaining future-oriented items. Further evidence indicated that the present-oriented factor and the 12-item CFC Scale perform similarly in terms of internal consistency and convergent validity. The structure and content of the future-oriented factor(s) is unclear. From the findings, the authors raise questions regarding the construct validity of the CFC Scale, the interpretation of its results, and the usefulness of the CFC scale in its current form in applied research.
NASA Astrophysics Data System (ADS)
Hsieh, Shang Yu; Neubauer, Franz; Cloetingh, Sierd; Willingshofer, Ernst; Sokoutis, Dimitrios
2014-05-01
The internal structure of major strike-slip faults is still poorly understood, particularly how the deep structure could be inferred from its surface expression (Molnar and Dayem, 2011 and references therein). Previous analogue experiments suggest that the convergence angle is the most influential factor (Leever et al., 2011). Further analogue modeling may allow a better understanding how to extrapolate surface structures to the subsurface geometry of strike-slip faults. Various scenarios of analogue experiments were designed to represent strike-slip faults in nature from different geological settings. As such key parameters, which are investigated in this study include: (a) the angle of convergence, (b) the thickness of brittle layer, (c) the influence of a rheological weak layer within the crust, and (d) influence of a thick and rheologically weak layer at the base of the crust. The latter aimed to simulate the effect of a hot metamorphic core complex or an alignment of uprising plutons bordered by a transtensional/transpressional strike-slip fault. The experiments are aimed to explain first order structures along major transcurrent strike-slip faults such as the Altyn, Kunlun, San Andrea and Greendale (Darfield earthquake 2010) faults. The preliminary results show that convergence angle significantly influences the overall geometry of the transpressive system with greater convergence angles resulting in wider fault zones and higher elevation. Different positions, densities and viscosities of weak rheological layers have not only different surface expressions but also affect the fault geometry in the subsurface. For instance, rheological weak material in the bottom layer results in stretching when experiment reaches a certain displacement and a buildup of a less segmented, wide positive flower structure. At the surface, a wide fault valley in the middle of the fault zone is the reflection of stretching along the velocity discontinuity at depth. In models with a thin and rheologically weaker layer in the middle of the brittle layer, deformation is distributed over more faults and the geometry of the fault zone below and above the weak zone shows significant differences, suggesting that the correlation of structures across a weak layer has to be supported by geophysical data, which help constraining the geometry of the deep part. This latter experiment has significantly similar phenomena in reality, such as few pressure ridges along Altyn fault. The experimental results underline the need to understand the role of the convergence angle and the influence of rheology on fault evolution, in order to connect between surface deformation and subsurface geometry. References Leever, K. A., Gabrielsen, R. H., Sokoutis, D., Willingshofer, E., 2011. The effect of convergence angle on the kinematic evolution of strain partitioning in transpressional brittle wedges: Insight from analog modeling and high-resolution digital image analysis. Tectonics, 30(2), TC2013. Molnar, P., Dayem, K.E., 2010. Major intracontinental strike-slip faults and contrasts in lithospheric strength. Geosphere, 6, 444-467.
Chiba, Rie; Umeda, Maki; Goto, Kyohei; Miyamoto, Yuki; Yamaguchi, Sosei; Kawakami, Norito
2017-01-01
The Recovery Knowledge Inventory (RKI) is one of the influential scales to assess knowledge and attitude toward recovery-oriented practices among mental health service providers. In the present study, we aimed to develop a Japanese version of RKI and examine the validity and reliability. We translated RKI into Japanese by reference to the guidelines for translating and adapting psychometric scales. A cross-sectional questionnaire survey was conducted with mental health service providers. Of a total of 475 eligible professionals, we used data from the 299 participants without missing value for the analyses (valid response rate = 62.9%). The questionnaire included Japanese RKI, Recovery Attitudes Questionnaire, The positive attitudes scale, and Japanese-language version of the Social Distance Scale. To examine the factorial validity of RKI, explanatory factor analysis and confirmatory factor analysis was employed. Convergent validity was assessed by calculating Pearson's correlation coefficients between the total RKI score and the scores for the other three scales. We also calculated Cronbach's α coefficients for the total score and for each domain of RKI to assess internal consistency reliability. The participants' mean age was 40.4 years and 30.4% were men. 20-item RKI did not provide any adequate or interpretable factor solutions at any number of factors by EFAs. Thus four items (#1, 4, 5, and 13) were subsequently eliminated in stages, then 16-item RKI was employed as a consequence for further analyses. EFA with four factor structures yielded marginally interpretable constitution. Each factor represented the knowledge regarding psychiatric symptoms and recovery; knowledge about the recovery process; the understanding of what is important for recovery; and the understanding of the challenges and responsibility in recovery, respectively. Subsequent CFA suggested good fit to the data. Good convergent validity and understandable internal consistency reliability were also observed. The Japanese 16-item RKI revealed reasonable factorial validity, good convergent validity, and understandable internal consistency reliability among mental health professionals. Japanese cultural settings seemed to influence the four-factor structure in the present study. It can be used for future study in Japan, while future large-scale research is required to ensure robust verification.
Marsh, Herbert W; Martin, Andrew J; Jackson, Susan
2010-08-01
Based on the Physical Self Description Questionnaire (PSDQ) normative archive (n = 1,607 Australian adolescents), 40 of 70 items were selected to construct a new short form (PSDQ-S). The PSDQ-S was evaluated in a new cross-validation sample of 708 Australian adolescents and four additional samples: 349 Australian elite-athlete adolescents, 986 Spanish adolescents, 395 Israeli university students, 760 Australian older adults. Across these six groups, the 11 PSDQ-S factors had consistently high reliabilities and invariant factor structures. Study 1, using a missing-by-design variation of multigroup invariance tests, showed invariance across 40 PSDQ-S items and 70 PSDQ items. Study 2 demonstrated factorial invariance over a 1-year interval (test-retest correlations .57-.90; Mdn = .77), and good convergent and discriminant validity in relation to time. Study 3 showed good and nearly identical support for convergent and discriminant validity of PSDQ and PSDQ-S responses in relation to two other physical self-concept instruments.
The development and validation of the Physical Appearance Comparison Scale-Revised (PACS-R).
Schaefer, Lauren M; Thompson, J Kevin
2014-04-01
The Physical Appearance Comparison Scale (PACS; Thompson, Heinberg, & Tantleff, 1991) was revised to assess appearance comparisons relevant to women and men in a wide variety of contexts. The revised scale (Physical Appearance Comparison Scale-Revised, PACS-R) was administered to 1176 college females. In Study 1, exploratory factor analysis and parallel analysis using one half of the sample suggested a single factor structure for the PACS-R. Study 2 utilized the remaining half of the sample to conduct confirmatory factor analysis, item analysis, and to examine the convergent validity of the scale. These analyses resulted in an 11-item measure that demonstrated excellent internal consistency and convergent validity with measures of body satisfaction, eating pathology, sociocultural influences on appearance, and self-esteem. Regression analyses demonstrated the utility of the PACS-R in predicting body satisfaction and eating pathology. Overall, results indicate that the PACS-R is a reliable and valid tool for assessing appearance comparison tendencies in women. Copyright © 2014. Published by Elsevier Ltd.
GITLIN, LAURA N.; ROTH, DAVID L.; BURGIO, LOUIS D.; LOEWENSTEIN, DAVID A.; WINTER, LARAINE; NICHOLS, LINDA; ARGÜELLES, SOLEDAD; CORCORAN, MARY; BURNS, ROBERT; MARTINDALE, JENNIFER
2008-01-01
Objective To evaluate psychometric properties and response patterns of the Caregiver Assessment of Function and Upset (CAFU), a 15-item multidimensional measure of dependence in dementia patients and caregiver reaction. Method 640 families were administered the CAFU (53% White, 43% African American, and 4% mixed race and ethnicity). We created a random split of the sample and conducted exploratory factor analyses on Sample 1 and confirmatory factor analyses on Sample 2. Convergent and discriminant validity were evaluated using Spearman rank correlation coefficients. Results A two-factor structure for functional items was derived, and excellent factorial validity was obtained. Convergent and discriminant validity were obtained for function and upset measures. Differential response patterns for dependence and caregiver upset were found for caregiver race, relationship, and care recipient gender but not for caregiver gender. Discussion The CAFU is easily administered, reliable, and valid for evaluating appraisals of dependencies and upsetting care areas. PMID:15750049
Coherent convergent-beam time-resolved X-ray diffraction
Spence, John C. H.; Zatsepin, Nadia A.; Li, Chufeng
2014-01-01
The use of coherent X-ray lasers for structural biology allows the use of nanometre diameter X-ray beams with large beam divergence. Their application to the structure analysis of protein nanocrystals and single particles raises new challenges and opportunities. We discuss the form of these coherent convergent-beam (CCB) hard X-ray diffraction patterns and their potential use for time-resolved crystallography, normally achieved by Laue (polychromatic) diffraction, for which the monochromatic laser radiation of a free-electron X-ray laser is unsuitable. We discuss the possibility of obtaining single-shot, angle-integrated rocking curves from CCB patterns, and the dependence of the resulting patterns on the focused beam coordinate when the beam diameter is larger or smaller than a nanocrystal, or smaller than one unit cell. We show how structure factor phase information is provided at overlapping interfering orders and how a common phase origin between different shots may be obtained. Their use in refinement of the phase-sensitive intensity between overlapping orders is suggested. PMID:24914153
Factor structure of the Liebowitz Social Anxiety Scale for Children and Adolescents.
Storch, Eric A; Masia-Warner, Carrie; Heidgerken, Amanda D; Fisher, Paige H; Pincus, Donna B; Liebowitz, Michael R
2006-01-01
The purpose of this study was to evaluate the factor structure of the Liebowitz Social Anxiety Scale for Children and Adolescents (LSAS-CA). The LSAS-CA was administered to 225 children and adolescents as a component of various clinical studies. In addition, other measures of psychopathology and impairment were administered to a subgroup of the sample. Confirmatory factor analyses of the social interaction and performance subscales for the anxiety and avoidance ratings yielded poor fit indices. Exploratory factor analysis supported a two-factor solution with a higher order factor for the LSAS-CA anxiety and avoidance ratings. Based on item content, factors were named Social and School Performance. The internal consistency of the factors was high and the convergent and divergent validity was supported vis-à-vis correlations with measures of depression and social anxiety, and clinician ratings of impairment and functioning. Findings suggest that the anxiety and avoidance ratings are best explained by a two-factor solution that measures social anxiety and avoidance in social and school performance interactions. This factor structure appears to be a reliable and valid framework for assessing childhood social phobia.
Allen, James; Fok, Carlotta Ching Ting; Henry, David; Skewes, Monica
2012-09-01
Concerns in some settings regarding the accuracy and ethics of employing direct questions about alcohol use suggest need for alternative assessment approaches with youth. Umyuangcaryaraq is a Yup'ik Alaska Native word meaning "Reflecting." The Reflective Processes Scale was developed as a youth measure tapping awareness and thinking over potential negative consequences of alcohol misuse as a protective factor that includes cultural elements often shared by many other Alaska Native and American Indian cultures. This study assessed multidimensional structure, item functioning, and validity. Responses from 284 rural Alaska Native youth allowed bifactor analysis to assess structure, estimates of location and discrimination parameters, and convergent and discriminant validity. A bifactor model of the scale items with three content factors provided excellent fit to observed data. Item response theory analysis suggested a binary response format as optimal. Evidence of convergent and discriminant validity was established. The measure provides an assessment of reflective processes about alcohol that Alaska Native youth engage in when thinking about reasons not to drink. The concept of reflective processes has potential to extend understandings of cultural variation in mindfulness, alcohol expectancies research, and culturally mediated protective factors in Alaska Native and American Indian youth.
Milot, Tristan; Plamondon, André; Ethier, Louise S; Lemelin, Jean-Pascal; St-Laurent, Diane; Rousseau, Michel
2013-05-01
There is growing evidence that child neglect is an important risk factor for posttraumatic stress disorder (PTSD) and dissociation. Considering that the Child Behavior Checklist (CBCL) is a widely used measure, the possibility of using validated CBCL-derived trauma symptoms scales could be particularly useful to better understand how trauma symptoms develop among neglected children and adolescents. This study examined the factor structure of three CBCL-derived measures of PTSD and dissociation (namely, PTSD scale, Dissociation scale, and PTSD/Dissociation scale) in a sample of 239 neglected children and adolescents aged 6 to 18 years using the latest version of CBCL (CBCL 6-18). Evidence of convergent validity of these scales was also examined for participants aged 12 and under using two well-validated measures of PTSD and Dissociation: the Trauma Symptoms Checklist for Young Children and the Child Dissociation Checklist. Findings suggest that CBCL-derived measures of trauma symptoms, especially PTSD and Dissociations scales, may be of heuristic value in the study of trauma symptomatology in neglected samples. Factor structure and evidence of convergent validity were supported for these two scales. Results also provide further support to the well-established assumption that PTSD and dissociation are two related but different constructs.
A Screening Tool to Measure Eye Contact Avoidance in Boys with Fragile X Syndrome
ERIC Educational Resources Information Center
Hall, Scott S.; Venema, Kaitlin M.
2017-01-01
We examined the reliability, validity and factor structure of the Eye Contact Avoidance Scale (ECAS), a new 15-item screening tool designed to measure eye contact avoidance in individuals with fragile X syndrome (FXS). Internal consistency of the scale was acceptable to excellent and convergent validity with the Social Responsiveness Scale, Second…
The Dula dangerous driving index in China: an investigation of reliability and validity.
Qu, Weina; Ge, Yan; Jiang, Caihong; Du, Feng; Zhang, Kan
2014-03-01
The aim of this study was to translate the Dula Dangerous Driving Index (DDDI) into Chinese and to verify its reliability and validity. A total of 246 drivers completed the Chinese version of the DDDI and the Driver Behavior Questionnaire (DBQ). Specific sociodemographic variables and traffic violations were also measured. A confirmatory factor analysis confirmed the internal structure of the DDDI, and the four-factor model was supported in China. Measures of convergent and criterion validity demonstrated that the Chinese DDDI was valid. Its convergent validity was supported by its positive relationship with the DBQ, and its criterion validity was tested using its relationship with self-reported accident involvement and traffic violations. Finally, score comparisons between different demographic groups revealed significant differences, thereby linking age and driving years to dangerous driving. Copyright © 2013 Elsevier Ltd. All rights reserved.
An Epigenetic Gateway to Brain Tumor Cell Identity
Mack, Stephen C.; Hubert, Christopher G.; Miller, Tyler E.; Taylor, Michael D.; Rich, Jeremy N.
2017-01-01
Precise targeting of genetic lesions alone has been insufficient to extend brain tumor patient survival. Brain cancer cells are diverse in their genetic, metabolic, and microenvironmental compositions, accounting for their phenotypic heterogeneity and disparate responses to therapy. These factors converge at the level of the epigenome, representing a unified node that can be disrupted by pharmacologic inhibition. Aberrant epigenomes define many childhood and adult brain cancers, as demonstrated by widespread changes to DNA methylation patterns, redistribution of histone marks, and disruption of chromatin structure. In this review, we describe the convergence of genetic, metabolic, and micro-environmental factors upon mechanisms of epigenetic deregulation in brain cancer. We discuss how aberrant epigenetic pathways identified in brain tumors affect cell identity, cell state, and neoplastic transformation, in addition to the potential to exploit these alterations as novel therapeutic strategies for the treatment of brain cancer. PMID:26713744
Efficient relaxed-Jacobi smoothers for multigrid on parallel computers
NASA Astrophysics Data System (ADS)
Yang, Xiang; Mittal, Rajat
2017-03-01
In this Technical Note, we present a family of Jacobi-based multigrid smoothers suitable for the solution of discretized elliptic equations. These smoothers are based on the idea of scheduled-relaxation Jacobi proposed recently by Yang & Mittal (2014) [18] and employ two or three successive relaxed Jacobi iterations with relaxation factors derived so as to maximize the smoothing property of these iterations. The performance of these new smoothers measured in terms of convergence acceleration and computational workload, is assessed for multi-domain implementations typical of parallelized solvers, and compared to the lexicographic point Gauss-Seidel smoother. The tests include the geometric multigrid method on structured grids as well as the algebraic grid method on unstructured grids. The tests demonstrate that unlike Gauss-Seidel, the convergence of these Jacobi-based smoothers is unaffected by domain decomposition, and furthermore, they outperform the lexicographic Gauss-Seidel by factors that increase with domain partition count.
Soleimani, Mohammad Ali; Bahrami, Nasim; Yaghoobzadeh, Ameneh; Banihashemi, Hedieh; Nia, Hamid Sharif; Haghdoost, Ali Akbar
2016-01-01
Due to increasing recognition of the importance of death anxiety for understanding human nature, it is important that researchers who investigate death anxiety have reliable and valid methodology to measure. The purpose of this study was to evaluate the validity and reliability of the Persian version of Templer Death Anxiety Scale (TDAS) in family caregivers of cancer patients. A sample of 326 caregivers of cancer patients completed a 15-item questionnaire. Principal components analysis (PCA) followed by a varimax rotation was used to assess factor structure of the DAS. The construct validity of the scale was assessed using exploratory and confirmatory factor analyses. Convergent and discriminant validity were also examined. Reliability was assessed with Cronbach's alpha coefficients and construction reliability. Based on the results of the PCA and consideration of the meaning of our items, a three-factor solution, explaining 60.38% of the variance, was identified. A confirmatory factor analysis (CFA) then supported the adequacy of the three-domain structure of the DAS. Goodness-of-fit indices showed an acceptable fit overall with the full model {χ(2)(df) = 262.32 (61), χ(2)/df = 2.04 [adjusted goodness of fit index (AGFI) = 0.922, parsimonious comparative fit index (PCFI) = 0.703, normed fit Index (NFI) = 0.912, CMIN/DF = 2.048, root mean square error of approximation (RMSEA) = 0.055]}. Convergent and discriminant validity were shown with construct fulfilled. The Cronbach's alpha and construct reliability were greater than 0.70. The findings show that the Persian version of the TDAS has a three-factor structure and acceptable validity and reliability.
Banik, Ananya; Shenoy, U Sandhya; Saha, Sujoy; Waghmare, Umesh V; Biswas, Kanishka
2016-10-05
Understanding the basis of electronic transport and developing ideas to improve thermoelectric power factor are essential for production of efficient thermoelectric materials. Here, we report a significantly large thermoelectric power factor of ∼31.4 μW/cm·K 2 at 856 K in Ag and In co-doped SnTe (i.e., SnAg x In x Te 1+2x ). This is the highest power factor so far reported for SnTe-based material, which arises from the synergistic effects of Ag and In on the electronic structure and the improved electrical transport properties of SnTe. In and Ag play different but complementary roles in modifying the valence band structure of SnTe. In-doping introduces resonance levels inside the valence bands, leading to a significant improvement in the Seebeck coefficient at room temperature. On the other hand, Ag-doping reduces the energy separation between light- and heavy-hole valence bands by widening the principal band gap, which also results in an improved Seebeck coefficient. Additionally, Ag-doping in SnTe enhances the p-type carrier mobility. Co-doping of In and Ag in SnTe yields synergistically enhanced Seebeck coefficient and power factor over a broad temperature range because of the synergy of the introduction of resonance states and convergence of valence bands, which have been confirmed by first-principles density functional theory-based electronic structure calculations. As a consequence, we have achieved an improved thermoelectric figure of merit, zT ≈ 1, in SnAg 0.025 In 0.025 Te 1.05 at 856 K.
Development of the Muscle Dysmorphia Inventory (MDI).
Rhea, D J; Lantz, C D; Cornelius, A E
2004-12-01
The development of the 6-factor, 27-item Muscle Dysmorphia Inventory (MDI) was based on Lantz et al. proposed model of characteristics associated with Muscle Dysmorphia. quantitative procedures including item-to-total correlations, exploratory and confirmatory factor analyses, and structure equation modeling confirmed the construct validity of the scale. Convergent validity was also tested. bodybuilding and powerlifting competition venues, weight training facilities, and university athletic venues. the 1(st) study consisted of 77 experienced male free weight lifters. The 2(nd) study consisted of 156 male non-competitive bodybuilders and weight lifters and 168 elite level powerlifters and bodybuilders. The 3(rd) study consisted of 151 male and female bodybuilders and weight lifters. each participant completed demographic information, the MDI, Drive for Thinness subscale of the Eating Disorder Inventory, and the Training Dependency subscale of the Bodybuilding Dependence Scale. Reliability estimates (Cronbach's a) ranged from 0.72 to 0.94. Factor loadings in all 3 studies supported the 6-factor structure (size/symmetry, supplement use, exercise dependence, pharmacological use, dietary behavior, and physique protection). Much of the scale validation was focused on construct validity, however, correlations with the MDI's subscales and the Training Dependency subscale of the Bodybuilding Dependence Scale and the Drive for Thinness subscale of the Eating Disorder Inventory provided evidence of convergent validity also. From these preliminary results, the MDI appears to contribute to the identification of a newly formed disorder by offering a multi-dimensional measure of factors related to Muscle Dysmorphia.
Kennedy, Mary R T; Krause, Miriam O; O'Brien, Katy H
2014-01-01
The psychometric properties of the college challenges sub-set from The College Survey for Students with Brain Injury (CSS-BI) were investigated with adults with and without traumatic brain injury (TBI). Adults with and without TBI completed the CSS-BI. A sub-set of participants with TBI were interviewed, intentional and convergent validity were investigated, and the internal structure of the college challenges was analysed with exploratory factor analysis/principle component analysis. Respondents with TBI understood the items describing college challenges with evidence of intentional validity. More individuals with TBI than controls endorsed eight of the 13 college challenges. Those who reported more health issues endorsed more college challenges, demonstrating preliminary convergent validity. Cronbach's alphas of >0.85 demonstrated acceptable internal reliability. Factor analysis revealed a four-factor model for those with TBI: studying and learning (Factor 1), time management and organization (Factor 2), social (Factor 3) and nervousness/anxiety (Factor 4). This model explained 72% and 69% of the variance for those with and without TBI, respectively. The college challenges sub-set from the CSS-BI identifies challenges that individuals with TBI face when going to college. Some challenges were related to two factors in the model, demonstrating the inter-connections of these experiences.
Validation of the Minority Stress Scale Among Italian Gay and Bisexual Men.
Pala, Andrea Norcini; Dell'Amore, Francesca; Steca, Patrizia; Clinton, Lauren; Sandfort, Theodorus; Rael, Christine
2017-12-01
The experience of sexual orientation stigma (e.g., homophobic discrimination and physical aggression) generates minority stress, a chronic form of psychosocial stress. Minority stress has been shown to have a negative effect on gay and bisexual men's (GBM's) mental and physical health, increasing the rates of depression, suicidal ideation, and HIV risk behaviors. In conservative religious settings, such as Italy, sexual orientation stigma can be more frequently and/or more intensively experienced. However, minority stress among Italian GBM remains understudied. The aim of this study was to explore the dimensionality, internal reliability, and convergent validity of the Minority Stress Scale (MSS), a comprehensive instrument designed to assess the manifestations of sexual orientation stigma. The MSS consists of 50 items assessing (a) Structural Stigma, (b) Enacted Stigma, (c) Expectations of Discrimination, (d) Sexual Orientation Concealment, (e) Internalized Homophobia Toward Others, (f) Internalized Homophobia toward Oneself, and (g) Stigma Awareness. We recruited an online sample of 451 Italian GBM to take the MSS. We tested convergent validity using the Perceived Stress Questionnaire. Through exploratory factor analysis, we extracted the 7 theoretical factors and an additional 3-item factor assessing Expectations of Discrimination From Family Members. The MSS factors showed good internal reliability (ordinal α > .81) and good convergent validity. Our scale can be suitable for applications in research settings, psychosocial interventions, and, potentially, in clinical practice. Future studies will be conducted to further investigate the properties of the MSS, exploring the association with additional health-related measures (e.g., depressive symptoms and anxiety).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, J.; Malliakas, C. D.; Wijayaratne, K.
2017-01-01
We have conducted a temperature- dependent angle-resolved photoemission spectroscopy (ARPES) study of the electronic structures of PbTe, PbSe and PbS. Our ARPES data provide direct evidence for the light-hole upper valence bands (UVBs) and hitherto undetected heavy-hole lower valence bands (LVBs) in these materials. An unusual temperature-dependent relative movement between these bands leads to a monotonic decrease in the energy separation between their maxima with increasing temperature, which is known as band convergence and has long been believed to be the driving factor behind extraordinary thermoelectric performances of these compounds at elevated temperatures.
NASA Astrophysics Data System (ADS)
Zhao, J.; Malliakas, C. D.; Wijayaratne, K.; Karlapati, V.; Appathurai, N.; Chung, D. Y.; Rosenkranz, S.; Kanatzidis, M. G.; Chatterjee, U.
2017-01-01
We have conducted a temperature-dependent angle-resolved photoemission spectroscopy (ARPES) study of the electronic structures of PbTe, PbSe and PbS. Our ARPES data provide direct evidence for the light-hole upper valence bands (UVBs) and hitherto undetected heavy-hole lower valence bands (LVBs) in these materials. An unusual temperature-dependent relative movement between these bands leads to a monotonic decrease in the energy separation between their maxima with increasing temperature, which is known as band convergence and has long been believed to be the driving factor behind extraordinary thermoelectric performances of these compounds at elevated temperatures.
NASA Astrophysics Data System (ADS)
Lee, Bum Han; Lee, Sung Keun
2017-10-01
The effect of the structural heterogeneity of porous networks on the water distribution in porous media, initially saturated with immiscible fluid followed by increasing durations of water injection, remains one of the important problems in hydrology. The relationship among convergence rates (i.e., the rate of fluid saturation with varying injection time) and the macroscopic properties and structural parameters of porous media have been anticipated. Here, we used nuclear magnetic resonance (NMR) micro-imaging to obtain images (down to ∼50 μm resolution) of the distribution of water injected for varying durations into porous networks that were initially saturated with silicone oil. We then established the relationships among the convergence rates, structural parameters, and transport properties of porous networks. The volume fraction of the water phase increases as the water injection duration increases. The 3D images of the water distributions for silica gel samples are similar to those of the glass bead samples. The changes in water saturation (and the accompanying removal of silicone oil) and the variations in the volume fraction, specific surface area, and cube-counting fractal dimension of the water phase fit well with the single-exponential recovery function { f (t) = a [ 1 -exp (- λt) ] } . The asymptotic values (a, i.e., saturated value) of the properties of the volume fraction, specific surface area, and cube-counting fractal dimension of the glass bead samples were greater than those for the silica gel samples primarily because of the intrinsic differences in the porous networks and local distribution of the pore size and connectivity. The convergence rates of all of the properties are inversely proportional to the entropy length and permeability. Despite limitations of the current study, such as insufficient resolution and uncertainty for the estimated parameters due to sparsely selected short injection times, the observed trends highlight the first analyses of the cube-counting fractal dimension (and other structural properties) and convergence rates in porous networks consisting of two fluid components. These results indicate that the convergence rates correlate with the geometric factor that characterizes the porous networks and transport property of the porous networks.
Individual differences in processing styles: validity of the Rational-Experiential Inventory.
Björklund, Fredrik; Bäckström, Martin
2008-10-01
In Study 1 (N= 203) the factor structure of a Swedish translation of Pacini and Epstein's Rational-Experiential Inventory (REI-40) was investigated using confirmatory factor analysis. The hypothesized model with rationality and experientiality as orthogonal factors had satisfactory fit to the data, significantly better than alternative models (with two correlated factors or a single factor). Inclusion of "ability" and "favorability" subscales for rationality and experientiality increased fit further. It was concluded that the structural validity of the REI is adequate. In Study 2 (N= 72) the REI-factors were shown to have theoretically meaningful correlations to other personality traits, indicating convergent and discriminant validity. Finally, scores on the rationality scale were negatively related to risky choice framing effects in Kahneman and Tversky's Asian disease task, indicating concurrent validity. On the basis of these findings it was concluded that the test has satisfactory psychometric properties.
Hrabosky, Joshua I.; White, Marney A.; Masheb, Robin M.; Rothschild, Bruce S.; Burke-Martindale, Carolyn H.; Grilo, Carlos M.
2013-01-01
Objective Despite increasing use of the Eating Disorder Examination-Questionnaire (EDE-Q) in bariatric surgery patients, little is known about the utility and psychometric performance of this self-report measure in this clinical group. The primary purpose of the current study was to evaluate the factor structure and construct validity of the EDE-Q in a large series of bariatric surgery candidates. Methods and Procedures Participants were 337 obese bariatric surgery candidates. Participants completed the EDE-Q and a battery of behavioral and psychological measures. Results Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) produced a 12-item, 4-factor structure of the EDE-Q. The four factors, interpreted as Dietary Restraint, Eating Disturbance, Appearance Concerns, and Shape/Weight Overvaluation, were found to be internally consistent and converged with other relevant measures of psychopathology. Discussion Factor analysis of the EDE-Q in bariatric surgery candidates did not replicate the original subscales but revealed an alternative factor structure. Future research must further evaluate the psychometric properties, including the factor structure, of the EDE-Q in this and other diverse populations and consider means of improving this measure's ability to best assess eating-related pathology in bariatric surgery patients. PMID:18379561
ERIC Educational Resources Information Center
Buzzanell, Patrice M.; And Others
1996-01-01
Explores whether telephone callers converge to structural and relational message aspects found in recorded answering machine messages. Finds that callers exhibited greater convergence to relational than to structural aspects, and that both female and male callers converged with levels of immediacy in answering machine messages. Outlines…
Wang, Li; Long, Di; Li, Zhongquan; Armour, Cherie
2011-07-01
This present study examined the structure of posttraumatic stress disorder (PTSD) symptoms in a large sample of Chinese adolescents exposed to a deadly earthquake. A total of 2,800 middle school students aged 12 to 18 years participated in the study 6 months after the "Wenchuan Earthquake". Results of confirmatory factor analysis indicated that a five-factor intercorrelated model composed of intrusion, avoidance, numbing, dysphoric arousal, and anxious arousal, fit data significantly better than both the four-factor numbing model King et al. (Psychological Assessment 10:90-96, 1998) and the four-factor dysphoria model Simms et al. (Journal of Abnormal Psychology 111:637-647, 2002). Further examination of the external convergent and discriminant validity revealed that except for the dysphoric arousal factor, the remaining four PTSD factors yielded significantly different correlations with external measures of anxiety vs. depression. The findings add to the limited literature on the factor structure of PTSD in youths and on the five-factor PTSD model. In addition, they provide more detail into the latent psychopathological processes of PTSD, and inform the forthcoming DSM-5.
NASA Technical Reports Server (NTRS)
Milman, M. H.
1985-01-01
A factorization approach is presented for deriving approximations to the optimal feedback gain for the linear regulator-quadratic cost problem associated with time-varying functional differential equations with control delays. The approach is based on a discretization of the state penalty which leads to a simple structure for the feedback control law. General properties of the Volterra factors of Hilbert-Schmidt operators are then used to obtain convergence results for the feedback kernels.
Calculation of structural dynamic forces and stresses using mode acceleration
NASA Technical Reports Server (NTRS)
Blelloch, Paul
1989-01-01
While the standard mode acceleration formulation in structural dynamics has often been interpreted to suggest that the reason for improved convergence obtainable is that the dynamic correction factor is divided by the modal frequencies-squared, an alternative formulation is presented which clearly indicates that the only difference between mode acceleration and mode displacement data recovery is the addition of a static correction term. Attention is given to the advantages in numerical implementation associated with this alternative, as well as to an illustrative example.
Li, Wylie Wai Yee; Lam, Wendy Wing Tak; Shun, Shiow-Ching; Lai, Yeur-Hur; Law, Wai-Lun; Poon, Jensen; Fielding, Richard
2013-01-01
Background Accurate assessment of unmet supportive care needs is essential for optimal cancer patient care. This study used confirmatory factor analysis (CFA) to test the known factor structures of the short form of Supportive Care Need Survey (SCNS-34) in Hong Kong and Taiwan Chinese patients diagnosed with colorectal cancer (CRC). Methods 360 Hong Kong and 263 Taiwanese Chinese CRC patients completed the Chinese version of SCNS-SF34. Comparative measures (patient satisfaction, anxiety, depression, and symptom distress) tested convergent validity while known group differences were examined to test discriminant validity. Results The original 5-factor and recent 4-factor models of the SCNS demonstrated poor data fit using CFA in both Hong Kong and Taiwan samples. Subsequently a modified five-factor model with correlated residuals demonstrated acceptable fit in both samples. Correlations demonstrated convergent and divergent validity and known group differences were observed. Conclusions While the five-factor model demonstrated a better fit for data from Chinese colorectal cancer patients, some of the items within its domain overlapped, suggesting item redundancy. The five-factor model showed good psychometric properties in these samples but also suggests conceptualization of unmet supportive care needs are currently inadequate. PMID:24146774
Pan, Tonya M; Mills, Sarah D; Fox, Rina S; Baik, Sharon H; Harry, Kadie M; Roesch, Scott C; Sadler, Georgia Robins; Malcarne, Vanessa L
2017-12-01
The Life Orientation Test-Revised (LOT-R) is a widely used measure of optimism and pessimism, with three positively worded and three negatively worded content items. This study examined the structural validity and invariance, internal consistency reliability, and convergent and divergent validity of the English and Spanish versions of the LOT-R among Hispanic Americans. A community sample of Hispanic Americans ( N = 422) completed self-report measures, including the LOT-R, Patient Health Questionnaire-9, and Generalized Anxiety Disorder-7, in their preferred language of English or Spanish. Based on the literature, four structural models were tested: one-factor , oblique two-factor , orthogonal two-factor method effects with positive specific factor , and orthogonal two-factor method effects with negative specific factor . Baseline support for both of the English and Spanish versions was not achieved for any model; in all models, the negatively worded items in Spanish had non-significant factor loadings. Therefore, the positively worded three-item optimism subscale of the LOT-R was examined separately and fit the data, with factor loadings equivalent across language-preference groups. Coefficient alphas for the optimism subscale were consistent across both language-preference groups (αs = .61 [English] and .66 [Spanish]). In contrast, the six-item total score and three-item pessimism subscale demonstrated extremely low or inconsistent alphas. Convergent and divergent validity were established for the optimism subscale in both languages. In sum, the optimism subscale of the LOT-R demonstrated minimally acceptable to good psychometric properties across English and Spanish language-preference groups. However, neither the total score nor the pessimism subscale showed adequate psychometric properties for Spanish-speaking Hispanic Americans, likely due to translation and cultural adaptation issues, and thus are not supported for use with this population.
ERIC Educational Resources Information Center
Ang, Rebecca P.; Lowe, Patricia A.; Yusof, Noradlin
2011-01-01
The present study investigated the factor structure, reliability, convergent and discriminant validity, and U.S. norms of the Revised Children's Manifest Anxiety Scale, Second Edition (RCMAS-2; C. R. Reynolds & B. O. Richmond, 2008a) scores in a Singapore sample of 1,618 school-age children and adolescents. Although there were small…
ERIC Educational Resources Information Center
Burns, G. Leonard; Walsh, James A.; Servera, Mateu; Lorenzo-Seva, Urbano; Cardo, Esther; Rodriguez-Fornells, Antoni
2013-01-01
Exploratory structural equation modeling (SEM) was applied to a multiple indicator (26 individual symptom ratings) by multitrait (ADHD-IN, ADHD-HI and ODD factors) by multiple source (mothers, fathers and teachers) model to test the invariance, convergent and discriminant validity of the Child and Adolescent Disruptive Behavior Inventory with 872…
ERIC Educational Resources Information Center
Clendenin, Aaron A.; Businelle, Michael S.; Kelley, Mary Lou
2005-01-01
The Sports Behavior Checklist (SBC) is subjected to a principal components analysis, and subscales are correlated with subscales of the Conners' Revised Parent Form and the Social Skills Rating System. Both of these analyses are conducted to determine the construct validity of the instrument. A subsample of lower socioeconomic status individuals…
Assessing adolescents' personality with the NEO PI-R.
De Fruyt, F; Mervielde, I; Hoekstra, H A; Rolland, J P
2000-12-01
The suitability of the Revised NEO Personality Inventory (NEO PI-R) to assess adolescents' personality traits was investigated in an unselected heterogeneous sample of 469 adolescents aged 12 to 17 years. They were further administered the Hierarchical Personality Inventory for Children (HiPIC) to allow an examination of convergent and discriminant validity. The adult NEO PI-R factor structure proved to be highly replicable in the sample of adolescents, with all facet scales primarily loading on the expected factors, independent of the age group. Domain and facet internal consistency coefficients were comparable to those obtained in adult samples, with less than 12% of the items showing corrected item-facet correlations below absolute value .20. Although, in general, adolescents reported few difficulties with the comprehensibility of the items, they tend to report more problems with the Openness to Ideas (05) and Openness to Values (06) items. Correlations between NEO PI-R and HiPIC scales underscored the convergent and discriminant validity of the NEO facets and HiPIC scales. It was concluded that the NEO PI-R in its present form is useful for assessing adolescents' traits at the primary level, but additional research is necessary to infer the most appropriate facet level structure.
Chatterji, Madhabi
2002-01-01
This study examines validity of data generated by the School Readiness for Reforms: Leader Questionnaire (SRR-LQ) using an iterative procedure that combines classical and Rasch rating scale analysis. Following content-validation and pilot-testing, principal axis factor extraction and promax rotation of factors yielded a five factor structure consistent with the content-validated subscales of the original instrument. Factors were identified based on inspection of pattern and structure coefficients. The rotated factor pattern, inter-factor correlations, convergent validity coefficients, and Cronbach's alpha reliability estimates supported the hypothesized construct properties. To further examine unidimensionality and efficacy of the rating scale structures, item-level data from each factor-defined subscale were subjected to analysis with the Rasch rating scale model. Data-to-model fit statistics and separation reliability for items and persons met acceptable criteria. Rating scale results suggested consistency of expected and observed step difficulties in rating categories, and correspondence of step calibrations with increases in the underlying variables. The combined approach yielded more comprehensive diagnostic information on the quality of the five SRR-LQ subscales; further research is continuing.
Psychometric Assessment of the Child Surgery Worries Questionnaire Among Portuguese Children.
Fernandes, Sara; Arriaga, Patrícia; Carvalho, Helena; Esteves, Francisco
2017-12-01
Worries are common in surgical patients, especially in children. The present study analyzed the factor structure and the psychometric properties of a Portuguese version of the Child Surgery Worries Questionnaire (CSWQ-P) in a Portuguese sample of 490 children. Exploratory factor analysis, conducted via principal axis factoring with oblimin rotation, provided evidence for a four-factor structure of the 21 item questionnaire. A confirmatory factor analysis was also conducted, showing the good fit of this solution. The CSWQ-P proved to have one more subscale than the original Spanish version CSWQ. Correlations with the children's trait anxiety provided evidence of convergent validity for the CSWQ-P. Females also scored higher on worries than males on all subscales. Psychometric properties of this revised version of the CSWQ provided support for use with young children, and indicate the CSWQ-P has value for use in healthcare practice and in clinical research.
Bayes factors for testing inequality constrained hypotheses: Issues with prior specification.
Mulder, Joris
2014-02-01
Several issues are discussed when testing inequality constrained hypotheses using a Bayesian approach. First, the complexity (or size) of the inequality constrained parameter spaces can be ignored. This is the case when using the posterior probability that the inequality constraints of a hypothesis hold, Bayes factors based on non-informative improper priors, and partial Bayes factors based on posterior priors. Second, the Bayes factor may not be invariant for linear one-to-one transformations of the data. This can be observed when using balanced priors which are centred on the boundary of the constrained parameter space with a diagonal covariance structure. Third, the information paradox can be observed. When testing inequality constrained hypotheses, the information paradox occurs when the Bayes factor of an inequality constrained hypothesis against its complement converges to a constant as the evidence for the first hypothesis accumulates while keeping the sample size fixed. This paradox occurs when using Zellner's g prior as a result of too much prior shrinkage. Therefore, two new methods are proposed that avoid these issues. First, partial Bayes factors are proposed based on transformed minimal training samples. These training samples result in posterior priors that are centred on the boundary of the constrained parameter space with the same covariance structure as in the sample. Second, a g prior approach is proposed by letting g go to infinity. This is possible because the Jeffreys-Lindley paradox is not an issue when testing inequality constrained hypotheses. A simulation study indicated that the Bayes factor based on this g prior approach converges fastest to the true inequality constrained hypothesis. © 2013 The British Psychological Society.
Examining the Latent Structure of the Delis-Kaplan Executive Function System.
Karr, Justin E; Hofer, Scott M; Iverson, Grant L; Garcia-Barrera, Mauricio A
2018-05-04
The current study aimed to determine whether the Delis-Kaplan Executive Function System (D-KEFS) taps into three executive function factors (inhibition, shifting, fluency) and to assess the relationship between these factors and tests of executive-related constructs less often measured in latent variable research: reasoning, abstraction, and problem solving. Participants included 425 adults from the D-KEFS standardization sample (20-49 years old; 50.1% female; 70.1% White). Eight alternative measurement models were compared based on model fit, with test scores assigned a priori to three factors: inhibition (Color-Word Interference, Tower), shifting (Trail Making, Sorting, Design Fluency), and fluency (Verbal/Design Fluency). The Twenty Questions, Word Context, and Proverb Tests were predicted in separate structural models. The three-factor model fit the data well (CFI = 0.938; RMSEA = 0.047), although a two-factor model, with shifting and fluency merged, fit similarly well (CFI = 0.929; RMSEA = 0.048). A bifactor model fit best (CFI = 0.977; RMSEA = 0.032) and explained the most variance in shifting indicators, but rarely converged among 5,000 bootstrapped samples. When the three first-order factors simultaneously predicted the criterion variables, only shifting was uniquely predictive (p < .05; R2 = 0.246-0.408). The bifactor significantly predicted all three criterion variables (p < .001; R2 = 0.141-242). Results supported a three-factor D-KEFS model (i.e., inhibition, shifting, and fluency), although shifting and fluency were highly related (r = 0.696). The bifactor showed superior fit, but converged less often than other models. Shifting best predicted tests of reasoning, abstraction, and problem solving. These findings support the validity of D-KEFS scores for measuring executive-related constructs and provide a framework through which clinicians can interpret D-KEFS results.
Complete convergence of randomly weighted END sequences and its application.
Li, Penghua; Li, Xiaoqin; Wu, Kehan
2017-01-01
We investigate the complete convergence of partial sums of randomly weighted extended negatively dependent (END) random variables. Some results of complete moment convergence, complete convergence and the strong law of large numbers for this dependent structure are obtained. As an application, we study the convergence of the state observers of linear-time-invariant systems. Our results extend the corresponding earlier ones.
Galindo-Murillo, Rodrigo; Roe, Daniel R; Cheatham, Thomas E
2015-05-01
The structure and dynamics of DNA are critically related to its function. Molecular dynamics simulations augment experiment by providing detailed information about the atomic motions. However, to date the simulations have not been long enough for convergence of the dynamics and structural properties of DNA. Molecular dynamics simulations performed with AMBER using the ff99SB force field with the parmbsc0 modifications, including ensembles of independent simulations, were compared to long timescale molecular dynamics performed with the specialized Anton MD engine on the B-DNA structure d(GCACGAACGAACGAACGC). To assess convergence, the decay of the average RMSD values over longer and longer time intervals was evaluated in addition to assessing convergence of the dynamics via the Kullback-Leibler divergence of principal component projection histograms. These molecular dynamics simulations-including one of the longest simulations of DNA published to date at ~44μs-surprisingly suggest that the structure and dynamics of the DNA helix, neglecting the terminal base pairs, are essentially fully converged on the ~1-5μs timescale. We can now reproducibly converge the structure and dynamics of B-DNA helices, omitting the terminal base pairs, on the μs time scale with both the AMBER and CHARMM C36 nucleic acid force fields. Results from independent ensembles of simulations starting from different initial conditions, when aggregated, match the results from long timescale simulations on the specialized Anton MD engine. With access to large-scale GPU resources or the specialized MD engine "Anton" it is possible for a variety of molecular systems to reproducibly and reliably converge the conformational ensemble of sampled structures. This article is part of a Special Issue entitled: Recent developments of molecular dynamics. Copyright © 2014. Published by Elsevier B.V.
Galindo-Murillo, Rodrigo; Roe, Daniel R.; Cheatham, Thomas E.
2014-01-01
Background The structure and dynamics of DNA are critically related to its function. Molecular dynamics (MD) simulations augment experiment by providing detailed information about the atomic motions. However, to date the simulations have not been long enough for convergence of the dynamics and structural properties of DNA. Methods MD simulations performed with AMBER using the ff99SB force field with the parmbsc0 modifications, including ensembles of independent simulations, were compared to long timescale MD performed with the specialized Anton MD engine on the B-DNA structure d(GCACGAACGAACGAACGC). To assess convergence, the decay of the average RMSD values over longer and longer time intervals was evaluated in addition to assessing convergence of the dynamics via the Kullback-Leibler divergence of principal component projection histograms. Results These MD simulations —including one of the longest simulations of DNA published to date at ~44 μs—surprisingly suggest that the structure and dynamics of the DNA helix, neglecting the terminal base pairs, are essentially fully converged on the ~1–5 μs timescale. Conclusions We can now reproducibly converge the structure and dynamics of B-DNA helices, omitting the terminal base pairs, on the μs time scale with both the AMBER and CHARMM C36 nucleic acid force fields. Results from independent ensembles of simulations starting from different initial conditions, when aggregated, match the results from long timescale simulations on the specialized Anton MD engine. General Significance With access to large-scale GPU resources or the specialized MD engine “Anton” it is possibly for a variety of molecular systems to reproducibly and reliably converge the conformational ensemble of sampled structures. PMID:25219455
Structural and reliability analysis of quality of relationship index in cancer patients.
Cousson-Gélie, Florence; de Chalvron, Stéphanie; Zozaya, Carole; Lafaye, Anaïs
2013-01-01
Among psychosocial factors affecting emotional adjustment and quality of life, social support is one of the most important and widely studied in cancer patients, but little is known about the perception of support in specific significant relationships in patients with cancer. This study examined the psychometric properties of the Quality of Relationship Inventory (QRI) by evaluating its factor structure and its convergent and discriminant validity in a sample of cancer patients. A total of 388 patients completed the QRI. Convergent validity was evaluated by testing the correlations between the QRI subscales and measures of general social support, anxiety and depression symptoms. Discriminant validity was examined by testing group comparison. The QRI's longitudinal invariance across time was also tested. Principal axis factor analysis with promax rotation identified three factors accounting for 42.99% of variance: perceived social support, depth, and interpersonal conflict. Estimates of reliability with McDonald's ω coefficient were satisfactory for all the QRI subscales (ω ranging from 0.75 - 0.85). Satisfaction from general social support was negatively correlated with the interpersonal conflict subscale and positively with the depth subscale. The interpersonal conflict and social support scales were correlated with depression and anxiety scores. We also found a relative stability of QRI subscales (measured 3 months after the first evaluation) and differences between partner status and gender groups. The Quality of Relationship Inventory is a valid tool for assessing the quality of social support in a particular relationship with cancer patients.
Wu, Li-Fen; Yang, Shu-Hui; Koo, Malcolm
2017-01-04
Spiritual well-being has become an increasingly important issue for the elderly people. The 12-item Spirituality Index of Well-Being (SIWB) is a well-validated instrument for assessing a patient's current spiritual state. However, the psychometric properties of the SIWB in the Chinese elderly populations are not known. Therefore, this study translated the SIWB into Chinese and evaluated its psychometric properties. The English version of the SIWB was first translated into Chinese based on the Brislin's translation model. The psychometric properties of the translated version of the SIWB (SIWB-C) was evaluated in 416 elderly Taiwanese recruited using a purposive sampling procedure from a medical center, a long-term care institution, and a community health center. Convergent validity was accessed using Pearson's correlation coefficients of the SIWB-C, the EQ-5D-3 L health-related quality of life scale, and the Geriatric Depression Scale-5 (GDS-5). Exploratory factor analysis with Varimax rotation was performed to determine the construct validity. Confirmatory factor analysis was conducted for verification of the quality of the factor structures and demonstrating the convergent validity of the SIWB-C. An internal consistency test based on the Cronbach's alpha coefficient and a stability test based on the Guttman split-half coefficient were also performed. Test-retest reliability was evaluated with intraclass correlation coefficient. Exploratory factor analysis confirmed the original two-dimensional structure of the scale. Confirmatory factor analysis indicated a well-fitting model and a fine convergent validity of the SIWB-C. The Cronbach's alpha coefficient and the Guttman split-half coefficient for the SIWB-C were 0.94 and 0.84, respectively. The correlations between the SIWB-C with EQ-5D-3 L and GDS-5 were 0.22 (p < 0.01) and 0.45 (p < 0.05), respectively. The intraclass correlation coefficient of the SIWB-C over a test-retest interval of two weeks was 0.989. The SIWB-C was found to be a potential useful measure of subjective spiritual well-being in elderly Taiwanese. Its application in assessing the spiritual well-being in Mandarin-speaking elderly population warrants further investigation.
A high order accurate finite element algorithm for high Reynolds number flow prediction
NASA Technical Reports Server (NTRS)
Baker, A. J.
1978-01-01
A Galerkin-weighted residuals formulation is employed to establish an implicit finite element solution algorithm for generally nonlinear initial-boundary value problems. Solution accuracy, and convergence rate with discretization refinement, are quantized in several error norms, by a systematic study of numerical solutions to several nonlinear parabolic and a hyperbolic partial differential equation characteristic of the equations governing fluid flows. Solutions are generated using selective linear, quadratic and cubic basis functions. Richardson extrapolation is employed to generate a higher-order accurate solution to facilitate isolation of truncation error in all norms. Extension of the mathematical theory underlying accuracy and convergence concepts for linear elliptic equations is predicted for equations characteristic of laminar and turbulent fluid flows at nonmodest Reynolds number. The nondiagonal initial-value matrix structure introduced by the finite element theory is determined intrinsic to improved solution accuracy and convergence. A factored Jacobian iteration algorithm is derived and evaluated to yield a consequential reduction in both computer storage and execution CPU requirements while retaining solution accuracy.
Visual fatigue modeling for stereoscopic video shot based on camera motion
NASA Astrophysics Data System (ADS)
Shi, Guozhong; Sang, Xinzhu; Yu, Xunbo; Liu, Yangdong; Liu, Jing
2014-11-01
As three-dimensional television (3-DTV) and 3-D movie become popular, the discomfort of visual feeling limits further applications of 3D display technology. The cause of visual discomfort from stereoscopic video conflicts between accommodation and convergence, excessive binocular parallax, fast motion of objects and so on. Here, a novel method for evaluating visual fatigue is demonstrated. Influence factors including spatial structure, motion scale and comfortable zone are analyzed. According to the human visual system (HVS), people only need to converge their eyes to the specific objects for static cameras and background. Relative motion should be considered for different camera conditions determining different factor coefficients and weights. Compared with the traditional visual fatigue prediction model, a novel visual fatigue predicting model is presented. Visual fatigue degree is predicted using multiple linear regression method combining with the subjective evaluation. Consequently, each factor can reflect the characteristics of the scene, and the total visual fatigue score can be indicated according to the proposed algorithm. Compared with conventional algorithms which ignored the status of the camera, our approach exhibits reliable performance in terms of correlation with subjective test results.
Construct Validity of the Autism Impact Measure (AIM).
Mazurek, Micah O; Carlson, Coleen; Baker-Ericzén, Mary; Butter, Eric; Norris, Megan; Kanne, Stephen
2018-01-17
The Autism Impact Measure (AIM) was designed to track incremental change in frequency and impact of core ASD symptoms. The current study examined the structural and convergent validity of the AIM in a large sample of children with ASD. The results of a series of exploratory and confirmatory factor analyses yielded a final model with five theoretically and empirically meaningful subdomains: Repetitive Behavior, Atypical Behavior, Communication, Social Reciprocity, and Peer Interaction. The final model showed very good fit both overall and for each of the five factors, indicating excellent structural validity. AIM subdomain scores were significantly correlated with measures of similar constructs across all five domains. The results provide further support for the psychometric properties of the AIM.
McCrae, Robert R; Terracciano, Antonio; De Fruyt, Filip; De Bolle, Marleen; Gelfand, Michele J; Costa, Paul T
2010-06-01
We examined properties of culture-level personality traits in ratings of targets (N=5,109) ages 12 to 17 in 24 cultures. Aggregate scores were generalizable across gender, age, and relationship groups and showed convergence with culture-level scores from previous studies of self-reports and observer ratings of adults, but they were unrelated to national character stereotypes. Trait profiles also showed cross-study agreement within most cultures, 8 of which had not previously been studied. Multidimensional scaling showed that Western and non-Western cultures clustered along a dimension related to Extraversion. A culture-level factor analysis replicated earlier findings of a broad Extraversion factor but generally resembled the factor structure found in individuals. Continued analysis of aggregate personality scores is warranted.
McCrae, Robert R.; Terracciano, Antonio; De Fruyt, Filip; De Bolle, Marleen; Gelfand, Michele J.; Costa, Paul T.; Aguilar-Vafaie, Maria E.; Ahn, Chang-kyu; Ahn, Hyun-nie; Alcalay, Lidia; Allik, Jüri; Avdeyeva, Tatyana V.; Blatný, Marek; Bratko, Denis; Brunner-Sciarra, Marina; Cain, Thomas R.; Chittcharat, Niyada; Crawford, Jarret T.; de Lima, Margarida P.; Fehr, Ryan; Ficková, Emília; Gülgöz, Sami; Hřebíčková, Martina; Jussim, Lee; Klinkosz, Waldemar; Knežević, Goran; de Figueroa, Nora Leibovich; Löckenhoff, Corinna E.; Martin, Thomas A.; Marušić, Iris; Mastor, Khairul Anwar; Nakazato, Katsuharu; Nansubuga, Florence; Porrata, Jose; Purić, Danka; Realo, Anu; Reátegui, Norma; Rolland, Jean-Pierre; Schmidt, Vanina; Sekowski, Andrzej; Shakespeare-Finch, Jane; Shimonaka, Yoshiko; Simonetti, Franco; Siuta, Jerzy; Szmigielska, Barbara; Vanno, Vitanya; Wang, Lei; Yik, Michelle
2010-01-01
We examined properties of culture-level personality traits in ratings of targets (N = 5,109) aged 12 to 17 in 24 cultures. Aggregate scores were generalizable across gender, age, and relationship groups and showed convergence with culture-level scores from previous studies of self-reports and observer ratings of adults, but they were unrelated to national character stereotypes. Trait profiles also showed cross-study agreement within most cultures, eight of which had not previously been studied. Multidimensional scaling showed that Western and non-Western cultures clustered along a dimension related to Extraversion. A culture-level factor analysis replicated earlier findings of a broad Extraversion factor, but generally resembled the factor structure found in individuals. Continued analysis of aggregate personality scores is warranted. PMID:20573127
Validation of the Minority Stress Scale Among Italian Gay and Bisexual Men
Pala, Andrea Norcini; Dell’Amore, Francesca; Steca, Patrizia; Clinton, Lauren; Sandfort, Theodorus; Rael, Christine
2017-01-01
The experience of sexual orientation stigma (e.g., homophobic discrimination and physical aggression) generates minority stress, a chronic form of psychosocial stress. Minority stress has been shown to have a negative effect on gay and bisexual men’s (GBM’s) mental and physical health, increasing the rates of depression, suicidal ideation, and HIV risk behaviors. In conservative religious settings, such as Italy, sexual orientation stigma can be more frequently and/or more intensively experienced. However, minority stress among Italian GBM remains understudied. The aim of this study was to explore the dimensionality, internal reliability, and convergent validity of the Minority Stress Scale (MSS), a comprehensive instrument designed to assess the manifestations of sexual orientation stigma. The MSS consists of 50 items assessing (a) Structural Stigma, (b) Enacted Stigma, (c) Expectations of Discrimination, (d) Sexual Orientation Concealment, (e) Internalized Homophobia Toward Others, (f) Internalized Homophobia toward Oneself, and (g) Stigma Awareness. We recruited an online sample of 451 Italian GBM to take the MSS. We tested convergent validity using the Perceived Stress Questionnaire. Through exploratory factor analysis, we extracted the 7 theoretical factors and an additional 3-item factor assessing Expectations of Discrimination From Family Members. The MSS factors showed good internal reliability (ordinal α > .81) and good convergent validity. Our scale can be suitable for applications in research settings, psychosocial interventions, and, potentially, in clinical practice. Future studies will be conducted to further investigate the properties of the MSS, exploring the association with additional health-related measures (e.g., depressive symptoms and anxiety). PMID:29479555
Merz, Erin L; Roesch, Scott C; Malcarne, Vanessa L; Penedo, Frank J; Llabre, Maria M; Weitzman, Orit B; Navas-Nacher, Elena L; Perreira, Krista M; Gonzalez, Franklyn; Ponguta, Liliana A; Johnson, Timothy P; Gallo, Linda C
2014-06-01
The Interpersonal Support Evaluation List-12 (ISEL-12; Cohen, Mermelstein, Kamarck, & Hoberman, 1985) is broadly employed as a short-form measure of the traditional ISEL, which measures functional (i.e., perceived) social support. The ISEL-12 can be scored by summing the items to create an overall social support score; three subscale scores representing appraisal, belonging, and tangible social support have also been proposed. Despite extensive use, studies of the psychometric properties of ISEL-12 scores have been limited, particularly among Hispanics/Latinos, the largest and fastest growing ethnic group in the United States. The current study investigated the reliability and structural and convergent validity of ISEL-12 scores using data from 5,313 Hispanics/Latinos who participated in the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study. Participants completed measures in English or Spanish and identified their ancestry as Dominican, Central American, Cuban, Mexican, Puerto Rican, or South American. Cronbach's alphas suggested adequate internal consistency for the total score for all languages and ancestry groups; coefficients for the subscale scores were not acceptable. Confirmatory factor analyses revealed that the one-factor and three-factor models fit the data equally well. Results from multigroup confirmatory factor analyses supported a similar one-factor structure with equivalent response patterns and variances between language groups and ancestry groups. Convergent validity analyses suggested that the total social support score related to scores of social network integration, life engagement, perceived stress, and negative affect (depression, anxiety) in the expected directions.
Starfelt, Louise Charlotte; Young, Ross McD; White, Katherine M; Palk, Gavan
2016-01-01
Alcohol expectancies likely play a role in people's perceptions of alcohol-involved sexual violence. However, no appropriate measure exists to examine this link comprehensively. The aim of this research was to develop an alcohol expectancy measure which captures young adults' beliefs about alcohol's role in sexual aggression and victimization. Two cross-sectional samples of young Australian adults (18-25 years) were recruited for scale development (Phase 1) and scale validation (Phase 2). In Phase 1, participants (N = 201; 38.3% males) completed an online survey with an initial pool of alcohol expectancy items stated in terms of three targets (self, men, women) to identify the scale's factor structure and most effective items. A revised alcohol expectancy scale was then administered online to 322 young adults (39.6% males) in Phase 2. To assess the predictive, convergent, and discriminant validity of the scale, participants also completed established measures of personality, social desirability, alcohol use, general and context-specific alcohol expectancies, and impulsiveness. Principal axis factoring (Phase 1) and confirmatory factor analysis (Phase 2) resulted in a target-equivalent five-factor structure for the final 66-item Drinking Expectancy Sexual Vulnerabilities Questionnaire (DESV-Q). The factors were labeled (1) Sexual Coercion, (2) Sexual Vulnerability, (3) Confidence, (4) Self-Centeredness, and (5) Negative Cognitive and Behavioral Changes. The measure demonstrated effective items, high internal consistency, and satisfactory predictive, convergent, and discriminant validity. The DESV-Q is a purpose-specific instrument that could be used in future research to elucidate people's attributions for alcohol-involved sexual aggression and victimization.
Factor structure and validation of the Attentional Control Scale.
Judah, Matt R; Grant, DeMond M; Mills, Adam C; Lechner, William V
2014-04-01
The Attentional Control Scale (ACS; Derryberry & Reed, 2002) has been used to assess executive control over attention in numerous studies, but no published data have examined the factor structure of the English version. The current studies addressed this need and tested the predictive and convergent validity of the ACS subscales. In Study 1, exploratory factor analysis yielded a two-factor model with Focusing and Shifting subscales. In Study 2, confirmatory factor analysis supported this model and suggested superior fit compared to the factor structure of the Icelandic version (Ólafsson et al., 2011). Study 3 examined correlations between the ACS subscales and measures of working memory, anxiety, and cognitive control. Study 4 examined correlations between the subscales and reaction times on a mixed-antisaccade task, revealing positive correlations for antisaccade performance and prosaccade latency with Focusing scores and between switch trial performance and Shifting scores. Additionally, the findings partially supported unique relationships between Focusing and trait anxiety and between Shifting and depression that have been noted in recent research. Although the results generally support the validity of the ACS, additional research using performance-based tasks is needed.
An Examination of the Partner Cyber Abuse Questionnaire in a College Student Sample.
Wolford-Clevenger, Caitlin; Zapor, Heather; Brasfield, Hope; Febres, Jeniimarie; Elmquist, JoAnna; Brem, Meagan; Shorey, Ryan C; Stuart, Gregory L
2016-01-01
To examine the factor structure and convergent validity of a newly developed measure of an understudied form of partner abuse, cyber abuse, and to examine the prevalence of, and gender differences in, victimization by cyber abuse. College students in a dating relationship ( N = 502) completed the Partner Cyber Abuse Questionnaire (Hamby, 2013), as well as measures of partner abuse victimization and depression. Using exploratory factor analysis, we determined a one-factor solution was the most statistically and conceptually best fitting model. The cyber abuse victimization factor was correlated with depressive symptoms and physical, psychological, and sexual partner abuse victimization, supporting the convergent validity of the measure. The overall prevalence of victimization by cyber abuse was 40%, with victimization by specific acts ranging from 2-31%. Men and women did not differ in their victimization by cyber abuse. Cyber abuse is prevalent among college students and occurs concurrently with other partner abuse forms and depressive symptoms. Given the interrelated nature of partner abuse forms, prevention and intervention programs should address partner abuse occurring in-person and through technology. Cyber abuse should also be considered in the conceptualization and measurement of partner abuse to more fully understand this social problem.
Nascimento, Maria Isabel do; Reichenheim, Michael Eduardo; Monteiro, Gina Torres Rego
2011-12-01
The objective of this study was to reassess the dimensional structure of a Brazilian version of the Scale of Satisfaction with Interpersonal Processes of General Medical Care, proposed originally as a one-dimensional instrument. Strict confirmatory factor analysis (CFA) and exploratory factor analysis modeled within a CFA framework (E/CFA) were used to identify the best model. An initial CFA rejected the one-dimensional structure, while an E/CFA suggested a two-dimensional structure. The latter structure was followed by a new CFA, which showed that the model without cross-loading was the most parsimonious, with adequate fit indices (CFI = 0.982 and TLI = 0.988), except for RMSEA (0.062). Although the model achieved convergent validity, discriminant validity was questionable, with the square-root of the mean variance extracted from dimension 1 estimates falling below the respective factor correlation. According to these results, there is not sufficient evidence to recommend the immediate use of the instrument, and further studies are needed for a more in-depth analysis of the postulated structures.
Introducing CGOLS: The Cholla Galactic Outflow Simulation Suite
NASA Astrophysics Data System (ADS)
Schneider, Evan E.; Robertson, Brant E.
2018-06-01
We present the Cholla Galactic OutfLow Simulations (CGOLS) suite, a set of extremely high resolution global simulations of isolated disk galaxies designed to clarify the nature of multiphase structure in galactic winds. Using the GPU-based code Cholla, we achieve unprecedented resolution in these simulations, modeling galaxies over a 20 kpc region at a constant resolution of 5 pc. The simulations include a feedback model designed to test the effects of different mass- and energy-loading factors on galactic outflows over kiloparsec scales. In addition to describing the simulation methodology in detail, we also present the results from an adiabatic simulation that tests the frequently adopted analytic galactic wind model of Chevalier & Clegg. Our results indicate that the Chevalier & Clegg model is a good fit to nuclear starburst winds in the nonradiative region of parameter space. Finally, we investigate the role of resolution and convergence in large-scale simulations of multiphase galactic winds. While our largest-scale simulations show convergence of observable features like soft X-ray emission, our tests demonstrate that simulations of this kind with resolutions greater than 10 pc are not yet converged, confirming the need for extreme resolution in order to study the structure of winds and their effects on the circumgalactic medium.
Tectonics, recent geodynamics and seismicity of Azerbaijan part of the Greater Caucasus
NASA Astrophysics Data System (ADS)
Aliyev, Fuad; Kangarli, Talat; Rahimov, Fuad; Murtuzov, Zaur; Aliyev, Ziya
2016-04-01
Transition area of the Eastern Caucasus - Caspian Megadepression corresponds to a periclinal submergence zone of the mountain folded structure of the Greater Caucasus under Pliocene-Holocenic sedimentary complex of Caspian megabasin. Being a part of Alpine-Himalayan folded belt, Greater Caucasus has formed during alpine stage of tectogenesis under geodynamic conditions of convergent interactions between Northern and Southern Caucasus continental microplates. This process has been accompanied by pseudosubduction of the first plate under the second with formation of allochtonous accretion prism above underthrust zone. Modern folding and napping structure of the orogeny has formed as a result of the horizontal movements of different phases and subphases of alpine tectogenesis, that are presented represented by Late Cimmerian - Wallachian tectonic phases within Azerbaijan territory. Limited by meridional fault-slip zones, Caspian megadepression present itself as a young structure that layered on sublatitudinal convergent zone and developed during Late Miocene (10 million years ago) as a flexure zone between two indenters which actively move northward provoking their separation from the African continent and Arabian plate in the west and secession from Central Iranian plate of the Lut block in the east. The acting movement of Arabian plate to the north results in accumulation of the horizontal stress at the current stage of tectogenesis. Current process reveals itself both in the fragmentation of Southern and Northern Caucasus continental microplates into various-size blocks along the general and anti-Caucasus trended faults, and in consideration horizontal and vertical movements within the convergence zone. All these factors define the complexity of geodynamic condition revealed here, in which seismic activity of a transition zone become apparent. There exist the seismic zones here that are confined both to a convergence line and to the fault zones that confine Caspian megadepression or complicate its' inner structure. Under lateral compression conditions, the small-size dynamic blocks that form the inner structure of the earth crust in a transition zone is standing as a reason of formation of the transpressive deformations, which combine moving along bordering of transversal dislocations with the compression structures like Main Caucasus strike faults in a trend of convergent (pseudosubduction) interaction of Southern and Northern Caucasus continental microplates. During such regime a multiple elastic stress accumulation zones are developing, that are confined to mentioned dislocations and their connection knots. Namely, exceeding of a breakage point of the rocks by accumulated elastic deformations, results in earthquakes and destructions in such tectonically vulnerable transition zones.
The Structure of Musical Preferences: A Five-Factor Model
Rentfrow, Peter J.; Goldberg, Lewis R.; Levitin, Daniel J.
2011-01-01
Music is a cross-cultural universal, a ubiquitous activity found in every known human culture. Individuals demonstrate manifestly different preferences in music, and yet relatively little is known about the underlying structure of those preferences. Here, we introduce a model of musical preferences based on listeners’ affective reactions to excerpts of music from a wide variety of musical genres. The findings from three independent studies converged to suggest that there exists a latent five-factor structure underlying music preferences that is genre-free, and reflects primarily emotional/affective responses to music. We have interpreted and labeled these factors as: 1) a Mellow factor comprising smooth and relaxing styles; 2) an Urban factor defined largely by rhythmic and percussive music, such as is found in rap, funk, and acid jazz; 3) a Sophisticated factor that includes classical, operatic, world, and jazz; 4) an Intense factor defined by loud, forceful, and energetic music; and 5) a Campestral factor comprising a variety of different styles of direct, and rootsy music such as is often found in country and singer-songwriter genres. The findings from a fourth study suggest that preferences for the MUSIC factors are affected by both the social and auditory characteristics of the music. PMID:21299309
Chittiboyina, Amar G.; Kumar, Gundluru Mahesh; Carvalho, Paulo B.; Liu, Yang; Zhou, Yu-Dong; Nagle, Dale G.
2010-01-01
The absolute stereo structure of the natural product laurenditerpenol (1S, 6R, 7S, 10R, 11R, 14S, 15R) has been accomplished from eight plausible stereoisomers by its first asymmetric total synthesis in a highly convergent and flexible synthetic pathway. Six stereoisomers of laurenditerpenol were synthesized and evaluated for their biological activity. PMID:18004798
Deutsch, Curtis K; McIlvane, William J
2013-01-01
The target article by Charney on behavior genetics/genomics discusses how numerous molecular factors can inform heritability estimations and genetic association studies. These factors find application in the search for genes for behavioral phenotypes, including neuropsychiatric disorders. We elaborate upon how single causal factors can generate multiple phenotypes, and discuss how multiple causal factors may converge on common neurodevelopmental mechanisms. PMID:23095384
ERIC Educational Resources Information Center
Martin, Jason
2013-01-01
Taylor series convergence is a complicated mathematical structure which incorporates multiple concepts. Therefore, it can be very difficult for students to initially comprehend. How might students make sense of this structure? How might experts make sense of this structure? To answer these questions, an exploratory study was conducted using…
NASA Technical Reports Server (NTRS)
Macfarlane, J. J.
1992-01-01
We investigate the convergence properties of Lambda-acceleration methods for non-LTE radiative transfer problems in planar and spherical geometry. Matrix elements of the 'exact' A-operator are used to accelerate convergence to a solution in which both the radiative transfer and atomic rate equations are simultaneously satisfied. Convergence properties of two-level and multilevel atomic systems are investigated for methods using: (1) the complete Lambda-operator, and (2) the diagonal of the Lambda-operator. We find that the convergence properties for the method utilizing the complete Lambda-operator are significantly better than those of the diagonal Lambda-operator method, often reducing the number of iterations needed for convergence by a factor of between two and seven. However, the overall computational time required for large scale calculations - that is, those with many atomic levels and spatial zones - is typically a factor of a few larger for the complete Lambda-operator method, suggesting that the approach should be best applied to problems in which convergence is especially difficult.
Miller, Joshua D; Lynam, Donald R; McCain, Jessica L; Few, Lauren R; Crego, Cristina; Widiger, Thomas A; Campbell, W Keith
2016-02-01
The Five-Factor Narcissism Inventory (FFNI) is a self-report measure of the traits linked to grandiose and vulnerable narcissism, as well as narcissistic personality disorder (NPD), from a five-factor model perspective (FFM). In the current studies, the factor structure of the FFNI was explored and the results supported the extraction of three factors: Antagonism (e.g., Arrogance), Neuroticism (e.g., Need for Admiration), and Agentic Extraversion (e.g., Authoritativeness). In Study 2, the FFNI factors manifested convergent validity with their corresponding Big Five domains and diverging relations with measures of grandiose and vulnerable narcissism, NPD, and self-esteem. Ultimately, the FFNI factors help explicate the differences between various expressions of narcissism such that all are related to Antagonism but differ with regard to Neuroticism (relevant to vulnerable narcissism and NPD) and Agentic Extraversion (relevant to grandiose narcissism and NPD). The results also highlight the complex relation between self-esteem and the traits that comprise narcissism measures.
Convergence of quasiparticle self-consistent GW calculations of transition metal monoxides
NASA Astrophysics Data System (ADS)
Das, Suvadip; Coulter, John E.; Manousakis, Efstratios
2015-03-01
We have investigated the electronic structure of the transition metal monoxides MnO, CoO, and NiO in their undistorted rock-salt structure within a fully iterated quasiparticle self-consistent GW (QPscGW) scheme. We have studied the convergence of the QPscGW method, i.e., how the quasiparticle energy eigenvalues and wavefunctions converge as a function of the QPscGW iterations, and compared the converged outputs obtained from different starting wavefunctions. We found that the convergence is slow and that a one-shot G0W0 calculation does not significantly improve the initial eigenvalues and states. In some cases the ``path'' to convergence may go through energy band reordering which cannot be captured by the simple initial unperturbed Hamiltonian. When a fully iterated solution is reached, the converged density of states, band-gaps and magnetic moments of these oxides are found to be only weakly dependent on the choice of the starting wavefunctions and in reasonable agreement with the experiment. National High Magnetic Field Laboratory.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tan, Gangjian; Shi, Fengyuan; Hao, Shiqiang
2015-04-22
We report a significant enhancement of the thermoelectric performance of p-type SnTe over a broad temperature plateau with a peak ZT value of similar to 1.4 at 923 K through In/Cd codoping and a CdS nanostructuring approach. Indium and cadmium play different but complementary roles in modifying the valence band structure of SnTe. Specifically, In-doping introduces resonant levels inside the valence bands, leading to a considerably improved Seebeck coefficient at low temperature. Cd-doping, however, increases the Seebeck coefficient of SnTe remarkably in the mid- to high-temperature region via a convergence of the light and heavy hole bands and an enlargementmore » of the band gap. Combining the two dopants in SnTe yields enhanced Seebeck coefficient and power factor over a wide temperature range due to the synergy of resonance levels and valence band convergence, as demonstrated by the Pisarenko plot and supported by first-principles band structure calculations. Moreover, these codoped samples can be hierarchically structured on all scales (atomic point defects by doping, nanoscale precipitations by CdS nanostructuring, and mesoscale grains by SPS treatment) to achieve highly effective phonon scattering leading to strongly reduced thermal conductivities. In addition to the high maximum ZT the resultant large average ZT of similar to 0.8 between 300 and 923 K makes SnTe an attractive p-type material for high-temperature thermoelectric power generation.« less
Problematic Smartphone Use: Investigating Contemporary Experiences Using a Convergent Design
Harkin, Lydia
2018-01-01
Internet-enabled smartphones are increasingly ubiquitous in the Western world. Research suggests a number of problems can result from mobile phone overuse, including dependence, dangerous and prohibited use. For over a decade, this has been measured by the Problematic Mobile Phone Use Questionnaire (PMPU-Q). Given the rapid developments in mobile technologies, changes of use patterns and possible problematic and addictive use, the aim of the present study was to investigate and validate an updated contemporary version of the PMPU-Q (PMPU-Q-R). A mixed methods convergent design was employed, including a psychometric survey (N = 512) alongside qualitative focus groups (N = 21), to elicit experiences and perceptions of problematic smartphone use. The results suggest the PMPU-Q-R factor structure can be updated to include smartphone dependence, dangerous driving, and antisocial smartphone use factors. Theories of problematic mobile phone use require consideration of the ubiquity and indispensability of smartphones in the present day and age, particularly regarding use whilst driving and in social interactions. PMID:29337883
Validation of the Weight Concerns Scale Applied to Brazilian University Students.
Dias, Juliana Chioda Ribeiro; da Silva, Wanderson Roberto; Maroco, João; Campos, Juliana Alvares Duarte Bonini
2015-06-01
The aim of this study was to evaluate the validity and reliability of the Portuguese version of the Weight Concerns Scale (WCS) when applied to Brazilian university students. The scale was completed by 1084 university students from Brazilian public education institutions. A confirmatory factor analysis was conducted. The stability of the model in independent samples was assessed through multigroup analysis, and the invariance was estimated. Convergent, concurrent, divergent, and criterion validities as well as internal consistency were estimated. Results indicated that the one-factor model presented an adequate fit to the sample and values of convergent validity. The concurrent validity with the Body Shape Questionnaire and divergent validity with the Maslach Burnout Inventory for Students were adequate. Internal consistency was adequate, and the factorial structure was invariant in independent subsamples. The results present a simple and short instrument capable of precisely and accurately assessing concerns with weight among Brazilian university students. Copyright © 2015 Elsevier Ltd. All rights reserved.
Problematic Smartphone Use: Investigating Contemporary Experiences Using a Convergent Design.
Kuss, Daria J; Harkin, Lydia; Kanjo, Eiman; Billieux, Joel
2018-01-16
Internet-enabled smartphones are increasingly ubiquitous in the Western world. Research suggests a number of problems can result from mobile phone overuse, including dependence, dangerous and prohibited use. For over a decade, this has been measured by the Problematic Mobile Phone Use Questionnaire (PMPU-Q). Given the rapid developments in mobile technologies, changes of use patterns and possible problematic and addictive use, the aim of the present study was to investigate and validate an updated contemporary version of the PMPU-Q (PMPU-Q-R). A mixed methods convergent design was employed, including a psychometric survey ( N = 512) alongside qualitative focus groups ( N = 21), to elicit experiences and perceptions of problematic smartphone use. The results suggest the PMPU-Q-R factor structure can be updated to include smartphone dependence, dangerous driving, and antisocial smartphone use factors. Theories of problematic mobile phone use require consideration of the ubiquity and indispensability of smartphones in the present day and age, particularly regarding use whilst driving and in social interactions.
Swami, Viren; Barron, David; Weis, Laura; Voracek, Martin; Stieger, Stefan; Furnham, Adrian
2017-01-01
A number scales have been developed to measure conspiracist ideation, but little attention has been paid to the factorial validity of these scales. We reassessed the psychometric properties of four widely-used scales, namely the Belief in Conspiracy Theories Inventory (BCTI), the Conspiracy Mentality Questionnaire (CMQ), the Generic Conspiracist Beliefs Scale (GCBS), and the One-Item Conspiracy Measure (OICM). Eight-hundred-and-three U.S. adults completed all measures, along with measures of endorsement of 9/11 and anti-vaccination conspiracy theories. Through both exploratory and confirmatory factor analysis, we found that only the BCTI had acceptable factorial validity. We failed to confirm the factor structures of the CMQ and the GBCS, suggesting these measures had poor factorial validity. Indices of convergent validity were acceptable for the BCTI, but weaker for the other measures. Based on these findings, we provide suggestions for the future refinement in the measurement of conspiracist ideation.
Swami, Viren; Barron, David; Weis, Laura; Voracek, Martin; Stieger, Stefan; Furnham, Adrian
2017-01-01
A number scales have been developed to measure conspiracist ideation, but little attention has been paid to the factorial validity of these scales. We reassessed the psychometric properties of four widely-used scales, namely the Belief in Conspiracy Theories Inventory (BCTI), the Conspiracy Mentality Questionnaire (CMQ), the Generic Conspiracist Beliefs Scale (GCBS), and the One-Item Conspiracy Measure (OICM). Eight-hundred-and-three U.S. adults completed all measures, along with measures of endorsement of 9/11 and anti-vaccination conspiracy theories. Through both exploratory and confirmatory factor analysis, we found that only the BCTI had acceptable factorial validity. We failed to confirm the factor structures of the CMQ and the GBCS, suggesting these measures had poor factorial validity. Indices of convergent validity were acceptable for the BCTI, but weaker for the other measures. Based on these findings, we provide suggestions for the future refinement in the measurement of conspiracist ideation. PMID:28231266
Brief reasons for living inventory: a psychometric investigation.
Cwik, Jan Christopher; Siegmann, Paula; Willutzki, Ulrike; Nyhuis, Peter; Wolter, Marcus; Forkmann, Thomas; Glaesmer, Heide; Teismann, Tobias
2017-11-06
The present study aimed at validating the German version of the Brief Reasons for Living inventory (BRFL). Validity and reliability were established in a community (n = 339) and a clinical sample (n = 272). Convergent and discriminant validity were investigated, and confirmatory factor analyses were conducted for the complete BRFL as well as for a 10-item version excluding conditional items on child-related concerns. Furthermore, it was assessed how BRFL scores moderate the association between depression and suicide ideation. Results indicated an adequate fit of the data to the original factor structure. The total scale and the subscales of the German version of the BRFL had sufficient internal consistency, as well as good convergent and divergent validity. The BRFL demonstrated clinical utility by differentiating between participants with vs. without suicide ideation. Reasons for living proved to moderate the association between depression and suicide ideation. Results provide preliminary evidence that the BRFL may be a reliable and valid measure of adaptive reasons for living that can be used in clinic and research settings.
The quality-value proposition in health care.
Feazell, G Landon; Marren, John P
2003-01-01
Powerful forces are converging in US health care to finally cause recognition of the inherently logical relationship between quality and money. The forces, or marketplace "drivers," which are converging to compel recognition of the relationship between cost and quality are: (1) the increasing costs of care; (2) the recurrence of another medical malpractice crisis; and (3) the recognition inside and outside of health care that quality is inconsistent and unacceptable. It is apparent that hospital administrators, financial officers, board members, and medical staff leadership do not routinely do two things: (1) relate quality to finance; and (2) appreciate the intra-hospital structural problems that impede quality attainment. This article discusses these factors and offers a positive method for re-structuring quality efforts and focusing the hospital and its medical staff on quality. The simple but compelling thesis of the authors is that health care must immediately engage in the transformation to making quality of medical care the fundamental business strategy of the organization.
Wrzosek, Małgorzata; Szymiec, Eugeniusz; Klemens, Wiesława; Kotyło, Piotr; Schlee, Winfried; Modrzyńska, Małgorzata; Lang-Małecka, Agnieszka; Preis, Anna; Bulla, Jan
2016-01-01
Objective: The need for validated measures enabling clinicians to classify tinnitus patients according to the severity of tinnitus and screen the progress of therapies in our country led us to translate into Polish and to validate two tinnitus questionnaires, namely the Tinnitus Handicap Inventory (THI) and the Tinnitus Functional Index (TFI). Design: The original English versions of the questionnaires were translated into Polish and translated back to English by three independent translators. These versions were then finalized by the authors into a Polish THI (THI-Pl) and a Polish TFI (TFI-Pl). Participants from three laryngological centers in Poland anonymously answered the THI-Pl (N = 98) and the TFI-Pl (N = 108) in addition to the Polish versions of the Center for Epidemiologic Studies Depression Scale as a measure of self-perceived level of depression, and the Satisfaction With Life Scale to assess self-perceived quality of life. Both were used to determine discriminant validity. Two Visual Analog Scales were used to measure tinnitus annoyance and tinnitus loudness in order to determine convergent validity. Results: Similar to the original version of the THI, the THI-Pl showed a high internal consistency (Cronbach’s α = 0.93). The exploratory factor analysis revealed that the questionnaire has a three-factorial structure that does not correspond to the original division for functional, catastrophic, and emotional subscales. Convergent and discriminant validities were confirmed. The TFI-Pl showed high internal consistency (Cronbach’s α = 0.96) with the reliability ranging from 0.82 to 0.95 for its different subscales. Factor analysis confirmed an eight-factorial structure with factors assigning all items to appropriate subscales reported in the original version of the questionnaire. Discriminant and convergent validities were also confirmed for the TFI-Pl. Conclusion: We translated and validated the Polish versions of the THI and the TFI to make them suitable for clinical use in Poland. PMID:27965609
Swami, Viren; Tudorel, Otilia; Goian, Cosmin; Barron, David; Vintila, Mona
2017-12-01
We examined the psychometric properties of a Romanian translation of the 10-item Body Appreciation Scale-2 (BAS-2). A total of 453 university students from Romania completed the BAS-2, along with measures of disordered eating, self-esteem, satisfaction with life, and subjective happiness. In addition, a separate sample of university students (N=109) completed only the BAS-2 at two time-points three weeks apart. Principal-axis factor analysis indicated that BAS-2 scores had a one-dimensional factor structure in both women and men. Confirmatory factor analysis indicated that this factor structure had adequate fit, but invariance across sex was not supported. Further analyses indicated that BAS-2 scores evidenced internal consistency, convergent validity, and test-retest reliability in both women and men. These results suggest that BAS-2 scores reduce to one dimension in Romanian adults, but the lack of sex invariance may indicate that the same latent construct is not being measured in women and men. Copyright © 2017 Elsevier Ltd. All rights reserved.
Olino, Thomas M; McMakin, Dana L; Forbes, Erika E
2016-11-20
Positive emotionality, anhedonia, and reward sensitivity share motivational and experiential elements of approach motivation and pleasure. Earlier work has examined the interrelationships among these constructs from measures of extraversion. More recently, the Research Domain Criteria introduced the Positive Valence Systems as a primary dimension to better understand psychopathology. However, the suggested measures tapping this construct have not yet been integrated within the structural framework of personality, even at the level of self-report. Thus, this study conducted exploratory factor and exploratory bifactor analyses on 17 different dimensions relevant to approach motivation, spanning anhedonia, behavioral activation system functioning, and positive emotionality. Convergent validity of these dimensions is tested by examining associations with depressive symptoms. Relying on multiple indices of fit, our preferred model included a general factor along with specific factors of affiliation, positive emotion, assertiveness, and pleasure seeking. These factors demonstrated different patterns of association with depressive symptoms. We discuss the plausibility of this model and highlight important future directions for work on the structure of a broad Positive Valence Systems construct. © The Author(s) 2016.
Do convergent developmental mechanisms underlie convergent phenotypes?
NASA Technical Reports Server (NTRS)
Wray, Gregory A.
2002-01-01
Convergence is a pervasive evolutionary process, affecting many aspects of phenotype and even genotype. Relatively little is known about convergence in developmental processes, however, nor about the degree to which convergence in development underlies convergence in anatomy. A switch in the ecology of sea urchins from feeding to nonfeeding larvae illustrates how convergence in development can be associated with convergence in anatomy. Comparisons to more distantly related taxa, however, suggest that this association may be limited to relatively close phylogenetic comparisons. Similarities in gene expression during development provide another window into the association between convergence in developmental processes and convergence in anatomy. Several well-studied transcription factors exhibit likely cases of convergent gene expression in distantly related animal phyla. Convergence in regulatory gene expression domains is probably more common than generally acknowledged, and can arise for several different reasons. Copyright 2002 S. Karger AG, Basel.
Berzins, Tiffany L.; Garcia, Antonio F.; Acosta, Melina; Osman, Augustine
2017-01-01
Two instrument validation studies broadened the research literature exploring the factor structure, internal consistency reliability, and concurrent validity of scores on the Social Anxiety and Depression Life Interference—24 Inventory (SADLI-24; Osman, Bagge, Freedenthal, Guiterrez, & Emmerich, 2011). Study 1 (N = 1065) was undertaken to concurrently appraise three competing factor models for the instrument: a unidimensional model, a two-factor oblique model and a bifactor model. The bifactor model provided the best fit to the study sample data. Study 2 (N = 220) extended the results from Study 1 with an investigation of the convergent and discriminant validity for the bifactor model of the SADLI-24 with multiple regression analyses and scale-level exploratory structural equation modeling. This project yields data that augments the initial instrument development investigations for the target measure. PMID:28781401
Measuring attitudes towards suicide: Preliminary evaluation of an attitude towards suicide scale.
Cwik, Jan Christopher; Till, Benedikt; Bieda, Angela; Blackwell, Simon E; Walter, Carolin; Teismann, Tobias
2017-01-01
Our study aimed to validate a previously published scale assessing attitudes towards suicide. Factor structure, convergent and discriminant validity, and predictive validity were investigated. Adult German participants (N=503; mean age=24.74years; age range=18-67years) anonymously completed a set of questionnaires. An exploratory factor analysis was conducted, and incongruous items were deleted. Subsequently, scale properties of the reduced scale and its construct validity were analyzed. A confirmatory factor analysis was then conducted in an independent sample (N=266; mean age=28.77years; age range=18-88years) to further confirm the factor structure of the questionnaire. Parallel analysis indicated a three-factor solution, which was also supported by confirmatory factor analysis: right to commit suicide, interpersonal gesture and resilience. The subscales demonstrated acceptable construct and discriminant validity. Cronbach's α for the subscales ranged from 0.67 to 0.83, explaining 49.70% of the total variance. Positive attitudes towards suicide proved to be predictive of suicide risk status, providing preliminary evidence for the utility of the scale. Future studies aiming to reproduce the factor structure in a more heterogeneous sample are warranted. Copyright © 2016 Elsevier Inc. All rights reserved.
Kawata, Ariane K; Wilson, Hilary; Ong, Siew Hwa; Kulich, Karoly; Coyne, Karin
2016-10-01
The aim of this study was to evaluate the factor structure and psychometric characteristics of the Hypoglycemia Perspectives Questionnaire (HPQ) assessing experience and perceptions of hypoglycemia in patients with type 2 diabetes mellitus (T2DM). HPQ was administered to adults with T2DM in a clinical sample from Cyprus (HYPO-Cyprus, n = 500) and a community sample in the United States (US, n = 1257) from the 2011 US National Health and Wellness Survey. Demographic and clinical data were collected. Analysis of HPQ data from two convenience samples examined item performance, factor structure, and HPQ measurement properties (reliability, convergent validity, known-groups validity). Analyses supported three HPQ domains: symptom concern (six items), compensatory behavior (five items), and worry (five items). Internal consistency was high for all three domains (all ≥0.75), supporting reliability. Convergent validity was supported by moderate Spearman correlations between HPQ domain scores and the Audit of Diabetes-Dependent Quality of Life (ADDQoL-19) total score. Patients with recent hypoglycemia events had significantly higher HPQ scores, supporting known-group validity. HPQ may be a valid and reliable measure capturing the experience and impact of hypoglycemia and useful in clinical trials and community-based settings.
McNamara, Bridgette J; Banks, Emily; Gubhaju, Lina; Williamson, Anna; Joshy, Grace; Raphael, Beverley; Eades, Sandra J
2014-12-01
To assess the cross-cultural validity of two Kessler psychological distress scales (K-10 and K-5) by examining their measurement properties among older Aboriginal and Torres Strait Islanders and comparing them to those in non-Aboriginal individuals from NSW Australia. Self-reported questionnaire data from the 45 and Up Study for 1,631 Aboriginal and 231,774 non-Aboriginal people were used to examine the factor structure, convergent validity, internal consistency and levels of missing data of K-10 and K-5. We found excellent agreement in classification of distress of Aboriginal participants by K-10 and K-5 (weighted kappa=0.87), high internal consistency (Cronbach's alpha K-10: 0.93, K-5: 0.88), and factor structures consistent with those for the total Australian population. Convergent validity was evidenced by a strong graded relationship between the level of distress and the odds of: problems with daily activities due to emotional problems; current treatment for depression or anxiety; and poor quality of life. K-10 and K-5 scales are promising tools for measuring psychological distress among Aboriginal and Torres Strait Islanders aged 45 and over in research and clinical settings. © 2014 Public Health Association of Australia.
Deng, Lu; Du, Jincheng
2018-01-14
Borosilicate glasses form an important glass forming system in both glass science and technologies. The structure and property changes of borosilicate glasses as a function of thermal history in terms of cooling rate during glass formation and simulation system sizes used in classical molecular dynamics (MD) simulation were investigated with recently developed composition dependent partial charge potentials. Short and medium range structural features such as boron coordination, Si and B Q n distributions, and ring size distributions were analyzed to elucidate the effects of cooling rate and simulation system size on these structure features and selected glass properties such as glass transition temperature, vibration density of states, and mechanical properties. Neutron structure factors, neutron broadened pair distribution functions, and vibrational density of states were calculated and compared with results from experiments as well as ab initio calculations to validate the structure models. The results clearly indicate that both cooling rate and system size play an important role on the structures of these glasses, mainly by affecting the 3 B and 4 B distributions and consequently properties of the glasses. It was also found that different structure features and properties converge at different sizes or cooling rates; thus convergence tests are needed in simulations of the borosilicate glasses depending on the targeted properties. The results also shed light on the complex thermal history dependence on structure and properties in borosilicate glasses and the protocols in MD simulations of these and other glass materials.
NASA Astrophysics Data System (ADS)
Deng, Lu; Du, Jincheng
2018-01-01
Borosilicate glasses form an important glass forming system in both glass science and technologies. The structure and property changes of borosilicate glasses as a function of thermal history in terms of cooling rate during glass formation and simulation system sizes used in classical molecular dynamics (MD) simulation were investigated with recently developed composition dependent partial charge potentials. Short and medium range structural features such as boron coordination, Si and B Qn distributions, and ring size distributions were analyzed to elucidate the effects of cooling rate and simulation system size on these structure features and selected glass properties such as glass transition temperature, vibration density of states, and mechanical properties. Neutron structure factors, neutron broadened pair distribution functions, and vibrational density of states were calculated and compared with results from experiments as well as ab initio calculations to validate the structure models. The results clearly indicate that both cooling rate and system size play an important role on the structures of these glasses, mainly by affecting the 3B and 4B distributions and consequently properties of the glasses. It was also found that different structure features and properties converge at different sizes or cooling rates; thus convergence tests are needed in simulations of the borosilicate glasses depending on the targeted properties. The results also shed light on the complex thermal history dependence on structure and properties in borosilicate glasses and the protocols in MD simulations of these and other glass materials.
Cosmic Reionization On Computers: Numerical and Physical Convergence
Gnedin, Nickolay Y.
2016-04-01
In this paper I show that simulations of reionization performed under the Cosmic Reionization On Computers (CROC) project do converge in space and mass, albeit rather slowly. A fully converged solution (for a given star formation and feedback model) can be determined at a level of precision of about 20%, but such a solution is useless in practice, since achieving it in production-grade simulations would require a large set of runs at various mass and spatial resolutions, and computational resources for such an undertaking are not yet readily available. In order to make progress in the interim, I introduce amore » weak convergence correction factor in the star formation recipe, which allows one to approximate the fully converged solution with finite resolution simulations. The accuracy of weakly converged simulations approaches a comparable, ~20% level of precision for star formation histories of individual galactic halos and other galactic properties that are directly related to star formation rates, like stellar masses and metallicities. Yet other properties of model galaxies, for example, their HI masses, are recovered in the weakly converged runs only within a factor of two.« less
Cosmic Reionization On Computers: Numerical and Physical Convergence
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gnedin, Nickolay Y.
In this paper I show that simulations of reionization performed under the Cosmic Reionization On Computers (CROC) project do converge in space and mass, albeit rather slowly. A fully converged solution (for a given star formation and feedback model) can be determined at a level of precision of about 20%, but such a solution is useless in practice, since achieving it in production-grade simulations would require a large set of runs at various mass and spatial resolutions, and computational resources for such an undertaking are not yet readily available. In order to make progress in the interim, I introduce amore » weak convergence correction factor in the star formation recipe, which allows one to approximate the fully converged solution with finite resolution simulations. The accuracy of weakly converged simulations approaches a comparable, ~20% level of precision for star formation histories of individual galactic halos and other galactic properties that are directly related to star formation rates, like stellar masses and metallicities. Yet other properties of model galaxies, for example, their HI masses, are recovered in the weakly converged runs only within a factor of two.« less
Areia, Neide P; Major, Sofia; Relvas, Ana P
2017-10-01
The aim of this study was to validate the Portuguese version of the Family Inventory of Needs (FIN). The FIN aims to measure important family needs and their fulfilment by a healthcare team. This cross-sectional study involved a sample of 364 family members of cancer patients, recruited from three medical institutions and through online recruitment. Three instruments were used: a socio-demographic questionnaire, the FIN and the Brief Symptom Inventory - 18 (BSI-18). Construct validity and reliability were considered regarding the FIN's psychometric properties. The method used to determine construct validity was factor structure analysis (confirmatory factor analysis), inter-factor correlations (Spearman's rank correlation) and convergent validity (Spearman's rank correlation). To assess scale reliability, the FIN's internal consistency was evaluated (Cronbach's alpha coefficient). Descriptive and frequency statistics and tests to compare means were used to assess important needs and to what extent they were met. The four-factor structure of the FIN was confirmed. Thus, the FIN has four domains: Basic Information, Information on treatment and care, Support and Patient Comfort. Convergent validity with the BSI-18 was verified. Both subscales of the FIN and each domain exceeded the minimum reliability standard of 0.70. Family members also reported important needs that were not adequately met by healthcare professionals. The Portuguese version of the FIN seems to be a reliable and valid tool for identifying cancer patients' important family needs and to what extent these are met. Copyright © 2017 Elsevier Ltd. All rights reserved.
Merz, Erin L.; Roesch, Scott C.; Malcarne, Vanessa L.; Penedo, Frank J.; Llabre, Maria M.; Weitzman, Orit B.; Navas-Nacher, Elena L.; Perreira, Krista M.; Gonzalez, Franklyn; Ponguta, Liliana A.; Johnson, Timothy P.; Gallo, Linda C.
2014-01-01
The Interpersonal Support Evaluation List-12 (ISEL-12; Cohen, Mermelstein, Kamarck, & Hoberman, 1985) is broadly employed as a short-form measure of the traditional ISEL, which measures functional (i.e., perceived) social support. The ISEL-12 can be scored by summing the items to create an overall social support score; three subscale scores representing appraisal, belonging, and tangible social support have also been proposed. Despite extensive use, studies of the psychometric properties of ISEL-12 scores have been limited, particularly among Hispanics/Latinos, the largest and fastest growing ethnic group in the United States. The present study investigated the reliability, and structural and convergent validity of ISEL-12 scores using data from 5,313 Hispanics/Latinos who participated in the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary study. Participants completed measures in English or Spanish, and identified their ancestry as Dominican, Central American, Cuban, Mexican, Puerto Rican, or South American. Cronbach’s alphas suggested adequate internal consistency for the total score for all languages and ancestry groups; coefficients for the subscale scores were not acceptable. Confirmatory factor analyses revealed that the one-factor and three-factor models fit the data equally well. Results from multigroup confirmatory factor analyses supported a similar one-factor structure with equivalent response patterns and variances between language groups and ancestry groups. Convergent validity analyses suggested that the total social support score related to scores of social network integration, life engagement, perceived stress, and negative affect (depression, anxiety) in the expected directions. The total score of the ISEL-12 can be recommended for use among Hispanics/Latinos. PMID:24320763
Anderson, Jaime L; Sellbom, Martin; Ayearst, Lindsay; Quilty, Lena C; Chmielewski, Michael; Bagby, R Michael
2015-09-01
Our aim in the current study was to evaluate the convergence between Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) Section III dimensional personality traits, as operationalized via the Personality Inventory for DSM-5 (PID-5), and Minnesota Multiphasic Personality Inventory 2-Restructured Form (MMPI-2-RF) scale scores in a psychiatric patient sample. We used a sample of 346 (171 men, 175 women) patients who were recruited through a university-affiliated psychiatric facility in Toronto, Canada. We estimated zero-order correlations between the PID-5 and MMPI-2-RF substantive scale scores, as well as a series of exploratory structural equation modeling (ESEM) analyses to examine how these scales converged in multivariate latent space. Results generally showed empirical convergence between the scales of these two measures that were thematically meaningful and in accordance with conceptual expectations. Correlation analyses showed significant associations between conceptually expected scales, and the highest associations tended to be between scales that were theoretically related. ESEM analyses generated evidence for distinct internalizing, externalizing, and psychoticism factors across all analyses. These findings indicate convergence between these two measures and help further elucidate the associations between dysfunctional personality traits and general psychopathology. (c) 2015 APA, all rights reserved.
Montazeri, Ali; Vahdaninia, Mariam; Mousavi, Sayed Javad; Omidvari, Speideh
2009-01-01
Background The 12-item Short Form Health Survey (SF-12) as a shorter alternative of the SF-36 is largely used in health outcomes surveys. The aim of this study was to validate the SF-12 in Iran. Methods A random sample of the general population aged 15 years and over living in Tehran, Iran completed the SF-12. Reliability was estimated using internal consistency and validity was assessed using known groups comparison and convergent validity. In addition, the factor structure of the questionnaire was extracted by performing both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Results: In all, 5587 individuals were studied (2721 male and 2866 female). The mean age and formal education of the respondents were 35.1 (SD = 15.4) and 10.2 (SD = 4.4) years respectively. The results showed satisfactory internal consistency for both summary measures, that are the Physical Component Summary (PCS) and the Mental Component Summary (MCS); Cronbach's α for PCS-12 and MCS-12 was 0.73 and 0.72, respectively. Known-groups comparison showed that the SF-12 discriminated well between men and women and those who differed in age and educational status (P < 0.001). In addition, correlations between the SF-12 scales and single items showed that the physical functioning, role physical, bodily pain and general health subscales correlated higher with the PCS-12 score, while the vitality, social functioning, role emotional and mental health subscales more correlated with the MCS-12 score lending support to its good convergent validity. Finally the principal component analysis indicated a two-factor structure (physical and mental health) that jointly accounted for 57.8% of the variance. The confirmatory factory analysis also indicated a good fit to the data for the two-latent structure (physical and mental health). Conclusion In general the findings suggest that the SF-12 is a reliable and valid measure of health related quality of life among Iranian population. However, further studies are needed to establish stronger psychometric properties for this alternative form of the SF-36 Health Survey in Iran. PMID:19758427
Montazeri, Ali; Vahdaninia, Mariam; Mousavi, Sayed Javad; Omidvari, Speideh
2009-09-16
The 12-item Short Form Health Survey (SF-12) as a shorter alternative of the SF-36 is largely used in health outcomes surveys. The aim of this study was to validate the SF-12 in Iran. A random sample of the general population aged 15 years and over living in Tehran, Iran completed the SF-12. Reliability was estimated using internal consistency and validity was assessed using known groups comparison and convergent validity. In addition, the factor structure of the questionnaire was extracted by performing both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). In all, 5587 individuals were studied (2721 male and 2866 female). The mean age and formal education of the respondents were 35.1 (SD = 15.4) and 10.2 (SD = 4.4) years respectively. The results showed satisfactory internal consistency for both summary measures, that are the Physical Component Summary (PCS) and the Mental Component Summary (MCS); Cronbach's alpha for PCS-12 and MCS-12 was 0.73 and 0.72, respectively. Known-groups comparison showed that the SF-12 discriminated well between men and women and those who differed in age and educational status (P < 0.001). In addition, correlations between the SF-12 scales and single items showed that the physical functioning, role physical, bodily pain and general health subscales correlated higher with the PCS-12 score, while the vitality, social functioning, role emotional and mental health subscales more correlated with the MCS-12 score lending support to its good convergent validity. Finally the principal component analysis indicated a two-factor structure (physical and mental health) that jointly accounted for 57.8% of the variance. The confirmatory factory analysis also indicated a good fit to the data for the two-latent structure (physical and mental health). In general the findings suggest that the SF-12 is a reliable and valid measure of health related quality of life among Iranian population. However, further studies are needed to establish stronger psychometric properties for this alternative form of the SF-36 Health Survey in Iran.
Development and Psychometric Validation of the Dementia Attitudes Scale
O'Connor, Melissa L.; McFadden, Susan H.
2010-01-01
This study employed qualitative construct mapping and factor analysis to construct a scale to measure attitudes toward dementia. Five family caregivers, five professionals, and five college students participated in structured interviews. Qualitative analysis of the interviews led to a 46-item scale, which was reduced to 20 items following principal axis factoring with two different samples: college students (N = 302) and certified nursing assistant students (N = 145). Confirmatory factor analysis was then conducted with another sample of college students (N = 157). The final scale, titled the Dementia Attitudes Scale (DAS), essentially had a two-factor structure; the factors were labeled “dementia knowledge” and “social comfort.” Total-scale Cronbach's alphas ranged 0.83–0.85. Evidence for convergent validity was promising, as the DAS correlated significantly with scales that measured ageism and attitudes toward disabilities (range of correlations = 0.44–0.55; mean correlation = 0.50). These findings demonstrate the reliability and validity of the DAS, supporting its use as a research tool.
NASA Technical Reports Server (NTRS)
Toksoz, M. N.; Molnar, P.
1983-01-01
Studies of the structure of the continental collision zones using seismic and body waves, theoretical modelling of the thermal regime of the convergence processes, and studies of earthquake mechanisms and deformation aspects of the model are covered.
Psychometric properties of the Compulsive Exercise Test in an adolescent eating disorder population.
Formby, Pam; Watson, Hunna J; Hilyard, Anna; Martin, Kate; Egan, Sarah J
2014-12-01
The objective of this study was to evaluate the factor structure, validity, and reliability of the Compulsive Exercise Test (CET) in an adolescent clinical eating disorder population. The data source was the Helping to Outline Paediatric Eating Disorders (HOPE) Project, a prospective ongoing registry study comprising consecutive pediatric tertiary eating disorder referrals. Adolescents (N=104; 12-17years) with eating disorders completed the CET and other measures. Factor structure, convergent validity, and internal consistency were evaluated. Despite failing to identify a factor structure, the study provided clear evidence of the multidimensionality of the measure. The total score correlated significantly with measures of eating pathology, perfectionism, and frequency of exercise for shape and weight control (r=0.32-0.70, ps<0.05). More research into the multidimensional nature of compulsive exercise in clinical populations is needed. Further, research into compulsive exercise offers promise as an addition to existing cognitive behavioral models and treatments for eating disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.
The General Environment Fit Scale: A Factor Analysis and Test of Convergent Construct Validity
Beasley, Christopher; Jason, Leonard; Miller, Steven
2014-01-01
Person-environment fit (P-E fit) was initially espoused as an important construct in the field of community psychology; however, most of the theoretical and empirical development of the construct has been conducted by industrial/organizational (I/O) psychologists. In the current study, the GEFS—a P-E fit measure was developed from I/O and business management perspectives on fit—was administered to 246 attendees of an annual convention for residents and alumni of Oxford House (OH), a network of over 1400 mutual-help recovery homes. The authors conducted confirmatory factor and convergent construct validity analyses on the GEFS. The results suggested that the theoretical factor structure of the measure adequately fit the data, suggesting that the GEFS is a valid measure of P-E fit. OH resident fit with their recovery home was related to satisfaction, but not expected tenure. Exploratory analyses revealed that the sufficient supply of resident needs by the recovery home and similarity between residents and their housemates predicted satisfaction with the recovery home, but only similarity with housemates predicted how long residents intended to stay in the OHs. PMID:22071911
[German translation and validation of the Stress Appraisal Measure (SAM)].
Delahaye, M; Stieglitz, R D; Graf, M; Keppler, C; Maes, J; Pflueger, M
2015-05-01
In the present study, the German-language version of the Stress Appraisal Measure (SAM) by Peacock and Wong was validated in a student population. SAM is a relatively short questionnaire (28 items) that evaluates a current, stress-triggering event. The theoretical background is provided by the stress model of Lazarus and Folkman. 85 students (age: 23; 59 female, 26 male) were exposed to two stress scenarios in order to test whether they were suited to provoke stress. A factor analysis was performed and the internal consistency of the seven SAM scales was determined. In addition, the convergent validity of SAM with State and Trait Anxiety Inventory (STAI), Coping Inventory for Stressful Situations (CISS) and specific emotion scales was investigated via Pearson's product-moment correlation. The two stress scenarios were suited to evoke stress. The factor structure and the internal consistency of the individual scales, as well as the convergent validity of SAM were replicated with minor limitations in the present German version. Some items (especially from the fifth factor) were only replicated partially. SAM can also be employed in the German language version. © Georg Thieme Verlag KG Stuttgart · New York.
Development and validation of the pro-environmental behaviour scale for women's health.
Kim, HyunKyoung
2017-05-01
This study was aimed to develop and test the Pro-environmental Behavior Scale for Women's Health. Women adopt sustainable behaviours and alter their life styles to protect the environment and their health from environmental pollution. The conceptual framework of pro-environmental behaviours was based on Rogers' protection motivation theory and Weinstein's precaution adoption process model. The cross-sectional design was used for instrument development. The instrument development process consisted of a literature review, personal depth interviews and focus group interviews. The sample comprised 356 adult women recruited in April-May 2012 in South Korea using quota sampling. For construct validity, exploratory factor analysis was conducted to examine the factor structure, after which convergent and discriminant validity and known-group comparisons were tested. Principal component analysis yielded 17 items with four factors, including 'women's health protection,' 'chemical exposure prevention,' 'alternative consumption,' and 'community-oriented behaviour'. The Cronbach's α was 0·81. Convergent and discriminant validity were supported by performing correlations with other environmental-health and health-behaviour measures. Nursing professionals can reliably use the instrument to assess women's behaviours, which protect their health and the environment. © 2016 John Wiley & Sons Ltd.
Validation of the Resilience Scale for Adolescents in Norwegian adolescents 13-18 years.
Moksnes, Unni K; Haugan, Gørill
2018-03-01
Resilience is seen as a vital resource for coping and mental health in adolescents. However, there is no universally accepted theory or definition of resilience, leading to considerable challenges regarding how to operationalise and measure this construct. The study aimed at providing further knowledge of the psychometric properties (dimensionality, construct validity and internal consistency) of the 28-item version of the Resilience Scale for Adolescents (READ) in N = 1183 Norwegian adolescents, 13-18 years old. Dimensionality of READ was tested using confirmatory factor analysis (CFA). Convergent validity and reliability were tested using Pearson's correlation analysis, Cronbach's alpha and composite reliability. The CFA supported a modified, 20-item, five-factor structure with high reliability, supporting the dimensionality and internal consistency of the instrument. Convergent validity was confirmed where all factors correlated in expected directions with measures of sense of coherence, self-esteem, stress and depression. The psychometric properties of the READ need to be further evaluated in adolescents; however, the results indicate that a modified 20-item version of READ is adequate for assessing resilience in the present sample of Norwegian adolescents. © 2017 Nordic College of Caring Science.
An Examination of the Partner Cyber Abuse Questionnaire in a College Student Sample
Wolford-Clevenger, Caitlin; Zapor, Heather; Brasfield, Hope; Febres, Jeniimarie; Elmquist, JoAnna; Brem, Meagan; Shorey, Ryan C.; Stuart, Gregory L.
2015-01-01
Objective To examine the factor structure and convergent validity of a newly developed measure of an understudied form of partner abuse, cyber abuse, and to examine the prevalence of, and gender differences in, victimization by cyber abuse. Method College students in a dating relationship (N = 502) completed the Partner Cyber Abuse Questionnaire (Hamby, 2013), as well as measures of partner abuse victimization and depression. Results Using exploratory factor analysis, we determined a one-factor solution was the most statistically and conceptually best fitting model. The cyber abuse victimization factor was correlated with depressive symptoms and physical, psychological, and sexual partner abuse victimization, supporting the convergent validity of the measure. The overall prevalence of victimization by cyber abuse was 40%, with victimization by specific acts ranging from 2–31%. Men and women did not differ in their victimization by cyber abuse. Conclusions Cyber abuse is prevalent among college students and occurs concurrently with other partner abuse forms and depressive symptoms. Given the interrelated nature of partner abuse forms, prevention and intervention programs should address partner abuse occurring in-person and through technology. Cyber abuse should also be considered in the conceptualization and measurement of partner abuse to more fully understand this social problem. PMID:27014498
The structure of musical preferences: a five-factor model.
Rentfrow, Peter J; Goldberg, Lewis R; Levitin, Daniel J
2011-06-01
Music is a cross-cultural universal, a ubiquitous activity found in every known human culture. Individuals demonstrate manifestly different preferences in music, and yet relatively little is known about the underlying structure of those preferences. Here, we introduce a model of musical preferences based on listeners' affective reactions to excerpts of music from a wide variety of musical genres. The findings from 3 independent studies converged to suggest that there exists a latent 5-factor structure underlying music preferences that is genre free and reflects primarily emotional/affective responses to music. We have interpreted and labeled these factors as (a) a Mellow factor comprising smooth and relaxing styles; (b) an Unpretentious factor comprising a variety of different styles of sincere and rootsy music such as is often found in country and singer-songwriter genres; (c) a Sophisticated factor that includes classical, operatic, world, and jazz; (d) an Intense factor defined by loud, forceful, and energetic music; and (e) a Contemporary factor defined largely by rhythmic and percussive music, such as is found in rap, funk, and acid jazz. The findings from a fourth study suggest that preferences for the MUSIC factors are affected by both the social and the auditory characteristics of the music. 2011 APA, all rights reserved
Sanford, Keith; Rivers, Alannah Shelby
2017-10-01
When married parents go through a divorce, they may have concerns in 6 areas that are associated with postdivorce family adjustment. These include concerns about malice, power, custody, child rejection, esteem, and finances. The Parting Parent Concern Inventory assesses these concerns. It was developed in a series of preliminary studies, and this report focuses on results from 2 subsequent validation studies including 643 divorced parents with at least 1 child from their former marriage under the age of 18. Participants completed Internet assessments of their concerns and 14 different convergent validity criterion variables regarding aspects of child internalizing behavior, coparenting relationships, settlement outcomes, and personal well-being. Across both studies, the new measure of concerns fit an expected 6-dimensional factor structure. A total of 25 convergent validity correlations were tested, and all were significant. The distinctiveness of each concern scale was supported by the fact that all but 1 convergent association remained significant after controlling for variance explained by other concern scales. These results provide preliminary validation support for the new instrument. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Cockayne syndrome group A and B proteins converge on transcription-linked resolution of non-B DNA.
Scheibye-Knudsen, Morten; Tseng, Anne; Borch Jensen, Martin; Scheibye-Alsing, Karsten; Fang, Evandro Fei; Iyama, Teruaki; Bharti, Sanjay Kumar; Marosi, Krisztina; Froetscher, Lynn; Kassahun, Henok; Eckley, David Mark; Maul, Robert W; Bastian, Paul; De, Supriyo; Ghosh, Soumita; Nilsen, Hilde; Goldberg, Ilya G; Mattson, Mark P; Wilson, David M; Brosh, Robert M; Gorospe, Myriam; Bohr, Vilhelm A
2016-11-01
Cockayne syndrome is a neurodegenerative accelerated aging disorder caused by mutations in the CSA or CSB genes. Although the pathogenesis of Cockayne syndrome has remained elusive, recent work implicates mitochondrial dysfunction in the disease progression. Here, we present evidence that loss of CSA or CSB in a neuroblastoma cell line converges on mitochondrial dysfunction caused by defects in ribosomal DNA transcription and activation of the DNA damage sensor poly-ADP ribose polymerase 1 (PARP1). Indeed, inhibition of ribosomal DNA transcription leads to mitochondrial dysfunction in a number of cell lines. Furthermore, machine-learning algorithms predict that diseases with defects in ribosomal DNA (rDNA) transcription have mitochondrial dysfunction, and, accordingly, this is found when factors involved in rDNA transcription are knocked down. Mechanistically, loss of CSA or CSB leads to polymerase stalling at non-B DNA in a neuroblastoma cell line, in particular at G-quadruplex structures, and recombinant CSB can melt G-quadruplex structures. Indeed, stabilization of G-quadruplex structures activates PARP1 and leads to accelerated aging in Caenorhabditis elegans In conclusion, this work supports a role for impaired ribosomal DNA transcription in Cockayne syndrome and suggests that transcription-coupled resolution of secondary structures may be a mechanism to repress spurious activation of a DNA damage response.
Maclean, Katherine A.; Leoutsakos, Jeannie-Marie S.; Johnson, Matthew W.; Griffiths, Roland R.
2012-01-01
A large body of historical evidence describes the use of hallucinogenic compounds, such as psilocybin mushrooms, for religious purposes. But few scientific studies have attempted to measure or characterize hallucinogen-occasioned spiritual experiences. The present study examined the factor structure of the Mystical Experience Questionnaire (MEQ), a self-report measure that has been used to assess the effects of hallucinogens in laboratory studies. Participants (N=1602) completed the 43-item MEQ in reference to a mystical or profound experience they had had after ingesting psilocybin. Exploratory factor analysis of the MEQ retained 30 items and revealed a 4-factor structure covering the dimensions of classic mystical experience: unity, noetic quality, sacredness (F1); positive mood (F2); transcendence of time/space (F3); and ineffability (F4). MEQ factor scores showed good internal reliability and correlated with the Hood Mysticism Scale, indicating convergent validity. Participants who endorsed having had a mystical experience on psilocybin, compared to those who did not, had significantly higher factor scores, indicating construct validity. The 4-factor structure was confirmed in a second sample (N=440) and demonstrated superior fit compared to alternative models. The results provide initial evidence of the validity, reliability, and factor structure of a 30-item scale for measuring single, hallucinogen-occasioned mystical experiences, which may be a useful tool in the scientific study of mysticism. PMID:23316089
FFMPD scales: Comparisons with the FFM, PID-5, and CAT-PD-SF.
Crego, Cristina; Oltmanns, Joshua R; Widiger, Thomas A
2018-01-01
A series of 8 Five Factor Model Personality Disorder (FFMPD) scales have been developed to assess, from the perspective of the Five Factor Model (FFM), the maladaptive traits included within DSM-5 Section II personality disorders. An extensive body of FFMPD research has accumulated. However, for the most part, each study has been confined to the scales within 1 particular FFMPD Inventory. The current study considered 36 FFMPD scales, at least 1 from each of the 8 FFMPD inventories, including 8 scales considered to be from neuroticism, 8 from extraversion, 5 from openness, 8 from agreeableness, and 7 from conscientiousness. Their convergent, discriminant, and structural relationship with the FFM was considered, and compared with the structural relationship with the FFM obtained by the Personality Inventory for DSM-5 (PID-5) and the Computerized Adaptive Test-Personality Disorder-Static Form (CAT-PD-SF). Support for an FFM structure was obtained (albeit with agreeableness defining 1 factor and antagonism a separate factor). Similarities and differences across the FFMPD, PID-5, and CAT-PD-SF scales were highlighted. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
Bártolo, Ana; Monteiro, Sara; Pereira, Anabela
2017-09-28
: The Generalized Anxiety Disorder 7-item (GAD-7) scale has been presented as a reliable and valid measure to assess generalized anxiety symptoms in several clinical settings and among the general population. However, some researches did not support the original one-dimensional structure of the GAD-7 tool. Our main aim was to examine the factor structure of GAD-7 comparing the one-factor model fit with a two-factor model (3 somatic nature symptoms and 4 cognitive-emotional nature symptoms) in a sample of college students. This validation study with data collected cross-sectionally included 1,031 Portuguese college students attending courses in the six schools of the Polytechnic Institute of Coimbra, Coimbra, Portugal. Measures included the GAD-7, Hospital Anxiety and Depression Scale (HADS) and the University Student Risk Behaviors Questionnaire. Confirmatory factor analysis (CFA) procedures confirmed that neither factor structure was well fitting. Thus, a modified single factor model allowing the error terms of items associated with relaxing difficulties and irritability to covary was an appropriate solution. Additionally, this factor structure revealed configural and metric invariance across gender. A good convergent validity was found by correlating global anxiety and depression. However, this measure showed a weak association with consumption behaviors. Our results are relevant to clinical practice, since the comprehensive approach to GAD-7 contributes to knowing generalized anxiety symptoms trajectory and their correlates within the university setting.
Sepulveda, Ana R; Parks, Melissa; de Pellegrin, Yolanda; Anastasiadou, Dimitra; Blanco, Miriam
2016-04-01
Drive for Muscularity (DM) has been shown to be a relevant construct for measuring and understanding male body image. For this reason, it is important to have reliable and valid instruments with which to measure DM, and to date no such instruments exist in Spain. This study analyzes the psychometric and structural properties of the Drive for Muscularity Scale (DMS) in a sample of Spanish adolescent males (N=212), with the aim of studying the structural validity of the scale by using a confirmatory factor analysis (CFA), as well as analyzing the internal consistency and construct (convergent and discriminant) and concurrent validity of the instrument. After testing three models, results indicated that the best structure was a two-dimensional model, with the factors of muscularity-oriented body image (MBI) and muscularity behavior (MB). The scale showed good internal consistency (α=.90) and adequate construct validity. Furthermore, significant associations were found between DM and increased difficulties in emotional regulation (rho=.37) and low self-esteem (rho=-.19). Findings suggest that the two-factor structure may be used when assessing drive for muscularity among adolescent males in Spain. Copyright © 2016 Elsevier Ltd. All rights reserved.
Cosmological constraints from the convergence 1-point probability distribution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Patton, Kenneth; Blazek, Jonathan; Honscheid, Klaus
2017-06-29
Here, we examine the cosmological information available from the 1-point probability density function (PDF) of the weak-lensing convergence field, utilizing fast l-picola simulations and a Fisher analysis. We find competitive constraints in the Ωm–σ8 plane from the convergence PDF with 188 arcmin 2 pixels compared to the cosmic shear power spectrum with an equivalent number of modes (ℓ < 886). The convergence PDF also partially breaks the degeneracy cosmic shear exhibits in that parameter space. A joint analysis of the convergence PDF and shear 2-point function also reduces the impact of shape measurement systematics, to which the PDF is lessmore » susceptible, and improves the total figure of merit by a factor of 2–3, depending on the level of systematics. Finally, we present a correction factor necessary for calculating the unbiased Fisher information from finite differences using a limited number of cosmological simulations.« less
Cosmological constraints from the convergence 1-point probability distribution
NASA Astrophysics Data System (ADS)
Patton, Kenneth; Blazek, Jonathan; Honscheid, Klaus; Huff, Eric; Melchior, Peter; Ross, Ashley J.; Suchyta, Eric
2017-11-01
We examine the cosmological information available from the 1-point probability density function (PDF) of the weak-lensing convergence field, utilizing fast L-PICOLA simulations and a Fisher analysis. We find competitive constraints in the Ωm-σ8 plane from the convergence PDF with 188 arcmin2 pixels compared to the cosmic shear power spectrum with an equivalent number of modes (ℓ < 886). The convergence PDF also partially breaks the degeneracy cosmic shear exhibits in that parameter space. A joint analysis of the convergence PDF and shear 2-point function also reduces the impact of shape measurement systematics, to which the PDF is less susceptible, and improves the total figure of merit by a factor of 2-3, depending on the level of systematics. Finally, we present a correction factor necessary for calculating the unbiased Fisher information from finite differences using a limited number of cosmological simulations.
Maroufizadeh, Saman; Zareiyan, Armin; Sigari, Naseh
2014-05-01
Asthma is a major public health problem in the world, and recent findings suggest that stress influences asthma and asthma morbidity. The 10-item Perceived Stress Scale (PSS-10) is one of the most frequently used instruments to measure psychological stress. This study was conducted to evaluate the psychometric properties of the Persian versions of the PSS-10 in adults with asthma. In this descriptive cross-sectional study as a methodological research, 106 asthmatic patients referring to several clinics in Sanandaj (western Iran) were selected through convenience sampling. The PSS-10 and the 21-item Depression anxiety and stress scale (DASS-21) were administrated to all patients. Cronbach's alpha was used to evaluate reliability of PSS-10, and confirmatory factor analysis (CFA) and convergent validity were used to evaluate its validity. The results of confirmatory factor analysis indicated that a two-factor structure of PSS-10 provided a good fit to data. The Cronbach's alpha coefficients for negative factor, positive factor and total score (PSS-10) were 0.86, 0.83, and 0.90, respectively. The PSS-10 was positively correlated with the DASS-21 and its subscales, indicating an acceptable convergent validity. Female asthmatic patients scored higher on PSS-10 in comparison with male asthmatic patients. The Persian version of PSS-10 is a valid and reliable instrument to measure perceived stress in adults with asthma.
Psychometrics and latent structure of the IDS and QIDS with young adult students.
González, David Andrés; Boals, Adriel; Jenkins, Sharon Rae; Schuler, Eric R; Taylor, Daniel
2013-07-01
Students and young adults have high rates of suicide and depression, thus are a population of interest. To date, there is no normative psychometric information on the IDS and QIDS in these populations. Furthermore, there is equivocal evidence on the factor structure and subscales of the IDS. Two samples of young adult students (ns=475 and 1681) were given multiple measures to test the psychometrics and dimensionality of the IDS and QIDS. The IDS, its subscales, and QIDS had acceptable internal consistencies (αs=.79-90) and favorable convergent and divergent validity correlations. A three-factor structure and two Rasch-derived subscales best fit the IDS. The samples were collected from one university, which may influence generalizability. The IDS and QIDS are desirable measures of depressive symptoms when studying young adult students. Copyright © 2013 Elsevier B.V. All rights reserved.
Application of fully stressed design procedures to redundant and non-isotropic structures
NASA Technical Reports Server (NTRS)
Adelman, H. M.; Haftka, R. T.; Tsach, U.
1980-01-01
An evaluation is presented of fully stressed design procedures for sizing highly redundant structures including structures made of composite materials. The evaluation is carried out by sizing three structures: a simple box beam of either composite or metal construction; a low aspect ratio titanium wing; and a titanium arrow wing for a conceptual supersonic cruise aircraft. All three structures are sized by ordinary fully-stressed design (FSD) and thermal fully stressed design (TFSD) for combined mechanical and thermal loads. Where possible, designs are checked by applying rigorous mathematical programming techniques to the structures. It is found that FSD and TFSD produce optimum designs for the metal box beam, but produce highly non-optimum designs for the composite box beam. Results from the delta wing and arrow wing indicate that FSD and TFSD exhibits slow convergence for highly redundant metal structures. Further, TFSD exhibits slow oscillatory convergence behavior for the arrow wing for very high temperatures. In all cases where FSD and TFSD perform poorly either in obtaining nonoptimum designs or in converging slowly, the assumptions on which the algorithms are based are grossly violated. The use of scaling, however, is found to be very effective in obtaining fast convergence and efficiently produces safe designs even for those cases when FSD and TFSD alone are ineffective.
COSMIC REIONIZATION ON COMPUTERS: NUMERICAL AND PHYSICAL CONVERGENCE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gnedin, Nickolay Y., E-mail: gnedin@fnal.gov; Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637; Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637
In this paper I show that simulations of reionization performed under the Cosmic Reionization On Computers project do converge in space and mass, albeit rather slowly. A fully converged solution (for a given star formation and feedback model) can be determined at a level of precision of about 20%, but such a solution is useless in practice, since achieving it in production-grade simulations would require a large set of runs at various mass and spatial resolutions, and computational resources for such an undertaking are not yet readily available. In order to make progress in the interim, I introduce a weakmore » convergence correction factor in the star formation recipe, which allows one to approximate the fully converged solution with finite-resolution simulations. The accuracy of weakly converged simulations approaches a comparable, ∼20% level of precision for star formation histories of individual galactic halos and other galactic properties that are directly related to star formation rates, such as stellar masses and metallicities. Yet other properties of model galaxies, for example, their H i masses, are recovered in the weakly converged runs only within a factor of 2.« less
On the Structure of the Present-Day Convergence
ERIC Educational Resources Information Center
Korotayev, Andrey; Zinkina, Julia
2014-01-01
Purpose: A substantial number of researchers have investigated the global economic dynamics of this time to disprove unconditional convergence and refute its very idea, stating the phenomenon of conditional convergence instead. However, most respective papers limit their investigation period with the early or mid-2000s. In the authors' opinion,…
Convergence Estimates for Multidisciplinary Analysis and Optimization
NASA Technical Reports Server (NTRS)
Arian, Eyal
1997-01-01
A quantitative analysis of coupling between systems of equations is introduced. This analysis is then applied to problems in multidisciplinary analysis, sensitivity, and optimization. For the sensitivity and optimization problems both multidisciplinary and single discipline feasibility schemes are considered. In all these cases a "convergence factor" is estimated in terms of the Jacobians and Hessians of the system, thus it can also be approximated by existing disciplinary analysis and optimization codes. The convergence factor is identified with the measure for the "coupling" between the disciplines in the system. Applications to algorithm development are discussed. Demonstration of the convergence estimates and numerical results are given for a system composed of two non-linear algebraic equations, and for a system composed of two PDEs modeling aeroelasticity.
NASA Technical Reports Server (NTRS)
Desideri, J. A.; Steger, J. L.; Tannehill, J. C.
1978-01-01
The iterative convergence properties of an approximate-factorization implicit finite-difference algorithm are analyzed both theoretically and numerically. Modifications to the base algorithm were made to remove the inconsistency in the original implementation of artificial dissipation. In this way, the steady-state solution became independent of the time-step, and much larger time-steps can be used stably. To accelerate the iterative convergence, large time-steps and a cyclic sequence of time-steps were used. For a model transonic flow problem governed by the Euler equations, convergence was achieved with 10 times fewer time-steps using the modified differencing scheme. A particular form of instability due to variable coefficients is also analyzed.
Domínguez, Evelia; Martín, Patricia; Martín-Albo, José; Núñez, Juan L; León, Jaime
2010-11-01
The aim of the present research was to translate and to analyze the psychometric properties of the Spanish version of the Satisfaction of Psychological Needs Scale, using a sample of 284 athletes (204 male and 78 female). Results of the confirmatory factor analysis confirmed the correlated three-factor structure of the scale. Furthermore, the results showed evidence of convergence validity with the Basic Psychological Needs in Exercise Scale. The predictive validity was tested using a structural equation model in which task orientation climate predicted the three basic psychological needs and these, in turn, intrinsic motivation. Likewise, we documented evidence of reliability, analyzed as internal consistency and temporal stability. Results partially support the use of the Spanish version of the scale in sports.
Factor structure, validity and reliability of the Cambridge Worry Scale in a pregnant population.
Green, Josephine M; Kafetsios, Konstantinos; Statham, Helen E; Snowdon, Claire M
2003-11-01
This article presents the Cambridge Worry Scale (CWS), a content-based measure for assessing worries, and discusses its psychometric properties based on a longitudinal study of 1,207 pregnant women. Principal components analysis revealed a four-factor structure of women's concerns during pregnancy: socio-medical, own health, socio-economic and relational. The measure demonstrated good reliability and validity. Total CWS scores were strongly associated with state and trait anxiety (convergent validity) but also had significant and unique predictive value for mood outcomes (discriminant validity). The CWS discriminated better between women with different reproductive histories than measures of state and trait anxiety. We conclude that the CWS is a reliable and valid tool for assessing the extent and content of worries in specific situations.
Dynamics, morphogenesis and convergence of evolutionary quantum Prisoner's Dilemma games on networks
Yong, Xi
2016-01-01
The authors proposed a quantum Prisoner's Dilemma (PD) game as a natural extension of the classic PD game to resolve the dilemma. Here, we establish a new Nash equilibrium principle of the game, propose the notion of convergence and discover the convergence and phase-transition phenomena of the evolutionary games on networks. We investigate the many-body extension of the game or evolutionary games in networks. For homogeneous networks, we show that entanglement guarantees a quick convergence of super cooperation, that there is a phase transition from the convergence of defection to the convergence of super cooperation, and that the threshold for the phase transitions is principally determined by the Nash equilibrium principle of the game, with an accompanying perturbation by the variations of structures of networks. For heterogeneous networks, we show that the equilibrium frequencies of super-cooperators are divergent, that entanglement guarantees emergence of super-cooperation and that there is a phase transition of the emergence with the threshold determined by the Nash equilibrium principle, accompanied by a perturbation by the variations of structures of networks. Our results explore systematically, for the first time, the dynamics, morphogenesis and convergence of evolutionary games in interacting and competing systems. PMID:27118882
Cator, Lauren J; Zanti, Zacharo
2016-12-01
Several new mosquito control strategies will involve the release of laboratory reared males which will be required to compete with wild males for mates. Currently, the determinants of male mating success remain unclear. The presence of convergence between male and female harmonic flight tone frequencies during a mating attempt have been found to increase male mating success in the yellow fever mosquito, Aedes aegypti. Size has also been implicated as a factor in male mating success. Here, we investigated the relationships among body size, harmonic convergence signalling, and mating success. We predicted that harmonic convergence would be an important determinant of mating success and that large individuals would be more likely to converge. We used diet to manipulate male and female body size and then measured acoustic interactions during mating attempts between pairs of different body sizes. Additionally, we used playback experiments to measure the direct effect of size on signalling performance. In live pair interactions, harmonic convergence was found to be a significant predictor of copula formation. However, we also found interactions between harmonic convergence behaviour and body size. The probability that a given male successfully formed a copula was a consequence of his size, the size of the female encountered, and whether or not they converged. While convergence appears to be predictive of mating success regardless of size, the positive effect of convergence was modulated by size combinations. In playbacks, adult body size did not affect the probability of harmonic convergence responses. Both body size and harmonic convergence signalling were found to be determinants of male mating success. Our results suggest that in addition to measuring convergence ability of mass release lines that the size distribution of released males may need to be adjusted to complement the size distribution of females. We also found that diet amount alone cannot be used to increase male mating success or convergence probability. A clearer understanding of convergence behaviours, their relationship to mating success, and factors influencing convergence ability would provide the groundwork for improving the mating performance of laboratory reared lines.
Quantum Graphical Models and Belief Propagation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leifer, M.S.; Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo Ont., N2L 2Y5; Poulin, D.
Belief Propagation algorithms acting on Graphical Models of classical probability distributions, such as Markov Networks, Factor Graphs and Bayesian Networks, are amongst the most powerful known methods for deriving probabilistic inferences amongst large numbers of random variables. This paper presents a generalization of these concepts and methods to the quantum case, based on the idea that quantum theory can be thought of as a noncommutative, operator-valued, generalization of classical probability theory. Some novel characterizations of quantum conditional independence are derived, and definitions of Quantum n-Bifactor Networks, Markov Networks, Factor Graphs and Bayesian Networks are proposed. The structure of Quantum Markovmore » Networks is investigated and some partial characterization results are obtained, along the lines of the Hammersley-Clifford theorem. A Quantum Belief Propagation algorithm is presented and is shown to converge on 1-Bifactor Networks and Markov Networks when the underlying graph is a tree. The use of Quantum Belief Propagation as a heuristic algorithm in cases where it is not known to converge is discussed. Applications to decoding quantum error correcting codes and to the simulation of many-body quantum systems are described.« less
Psychometric properties of the Leisure Time Satisfaction Scale in family caregivers.
Martínez-Rodríguez, Silvia; Iraurgi, Ioseba; Gómez-Marroquin, Ignacio; Carrasco, María; Ortiz-Marqués, Nuria; Stevens, Alan B
2016-05-01
Despite evidence of the numerous benefits of leisure to health and well-being appropriate tools to assess this construct are lacking. The purpose of this work was to analyse the psychometric properties of the Spanish version of the Leisure Time Satisfaction (LTS). The sample was made up of 1048 primary family caregivers of dependent people. Scale structure was subjected to exploratory and confirmatory factor analysis. Concurrent and convergent validity were assessed by correlation with validated questionnaires for measuring burden (Zarit Burden Inventory - ZBI) and health (SF-36 Health Survey). The results show a high level of internal consistency (Cronbach’s alpha = .938) suitable fit of the dimensional model tested via confirmatory factor analysis (GFI = .925, BBNNFI= .996; IFI= .998, RMSEA= .043), and appropriate convergent validity with similar constructs (r = -.44 with ZBI; and r-values between .226 and .440 with SF-36 dimensions). Psychometric results obtained from the LTS are promising and the results enable us to draw the conclusion that it is a suitable tool for assessing caregivers’ leisure time satisfaction.
Validation of the Modified Fatigue Impact Scale in mild to moderate traumatic brain injury.
Schiehser, Dawn M; Delano-Wood, Lisa; Jak, Amy J; Matthews, Scott C; Simmons, Alan N; Jacobson, Mark W; Filoteo, J Vincent; Bondi, Mark W; Orff, Henry J; Liu, Lin
2015-01-01
To evaluate the validity of the Modified Fatigue Impact Scale (MFIS) in veterans with a history of mild to moderate traumatic brain injury (TBI). Veterans (N = 106) with mild (92%) or moderate (8%) TBI. Veterans Administration Health System. Factor structure, internal consistency, convergent validity, sensitivity, and specificity of the MFIS were examined. Principal component analysis identified 2 viable MFIS factors: a Cognitive subscale and a Physical/Activities subscale. Item analysis revealed high internal consistency of the MFIS Total scale and subscale items. Strong convergent validity of the MFIS scales was established with 2 Beck Depression Inventory II fatigue items. Receiver operating characteristic curve analysis revealed good to excellent accuracy of the MFIS in classifying fatigued versus nonfatigued individuals. The MFIS is a valid multidimensional measure that can be used to evaluate the impact of fatigue on cognitive and physical functioning in individuals with mild to moderate TBI. The psychometric properties of the MFIS make it useful for evaluating fatigue and provide the potential for improving research on fatigue in this population.
[Reliability and validity of Driving Anger Scale in professional drivers in China].
Li, Z; Yang, Y M; Zhang, C; Li, Y; Hu, J; Gao, L W; Zhou, Y X; Zhang, X J
2017-11-10
Objective: To assess the reliability and validity of the Chinese version of Driving Anger Scale (DAS) in professional drivers in China and provide a scientific basis for the application of the scale in drivers in China. Methods: Professional drivers, including taxi drivers, bus drivers, truck drivers and school bus drivers, were selected to complete the questionnaire. Cronbach's α and split-half reliability were calculated to evaluate the reliability of DAS, and content, contract, discriminant and convergent validity were performed to measure the validity of the scale. Results: The overall Cronbach's α of DAS was 0.934 and the split-half reliability was 0.874. The correlation coefficient of each subscale with the total scale was 0.639-0.922. The simplified version of DAS supported a presupposed six-factor structure, explaining 56.371% of the total variance revealed by exploratory factor analysis. The DAS had good convergent and discriminant validity, with the success rate of calibration experiment of 100%. Conclusion: DAS has a good reliability and validity in professional drivers in China, and the use of DAS is worth promoting in divers.
Internet addiction assessment tools: dimensional structure and methodological status.
Lortie, Catherine L; Guitton, Matthieu J
2013-07-01
Excessive internet use is becoming a concern, and some have proposed that it may involve addiction. We evaluated the dimensions assessed by, and psychometric properties of, a range of questionnaires purporting to assess internet addiction. Fourteen questionnaires were identified purporting to assess internet addiction among adolescents and adults published between January 1993 and October 2011. Their reported dimensional structure, construct, discriminant and convergent validity and reliability were assessed, as well as the methods used to derive these. Methods used to evaluate internet addiction questionnaires varied considerably. Three dimensions of addiction predominated: compulsive use (79%), negative outcomes (86%) and salience (71%). Less common were escapism (21%), withdrawal symptoms (36%) and other dimensions. Measures of validity and reliability were found to be within normally acceptable limits. There is a broad convergence of questionnaires purporting to assess internet addiction suggesting that compulsive use, negative outcome and salience should be covered and the questionnaires show adequate psychometric properties. However, the methods used to evaluate the questionnaires vary widely and possible factors contributing to excessive use such as social motivation do not appear to be covered. © 2013 Society for the Study of Addiction.
Lyon, Aaron R; Pullmann, Michael D; Dorsey, Shannon; Martin, Prerna; Grigore, Alexandra A; Becker, Emily M; Jensen-Doss, Amanda
2018-05-11
Measurement-based care (MBC) is an increasingly popular, evidence-based practice, but there are no tools with established psychometrics to evaluate clinician use of MBC practices in mental health service delivery. The current study evaluated the reliability, validity, and factor structure of scores generated from a brief, standardized tool to measure MBC practices, the Current Assessment Practice Evaluation-Revised (CAPER). Survey data from a national sample of 479 mental health clinicians were used to conduct exploratory and confirmatory factor analyses, as well as reliability and validity analyses (e.g., relationships between CAPER subscales and clinician MBC attitudes). Analyses revealed competing two- and three-factor models. Regardless of the model used, scores from CAPER subscales demonstrated good reliability and convergent and divergent validity with MBC attitudes in the expected directions. The CAPER appears to be a psychometrically sound tool for assessing clinician MBC practices. Future directions for development and application of the tool are discussed.
Alcaraz-Ibáñez, Manuel; Sicilia, Alvaro
2018-06-01
This study examined the psychometric properties of a Spanish translation of the Body and Appearance Self-Conscious Emotions Scale (BASES; Castonguay et al., 2014) in a sample of university Spanish students. A total of 815 participants enrolled in two public universities located in Almería and Elche, Spain, completed the BASES along with measures of social physique anxiety and positive/negative affect. Exploratory and confirmatory factor analyses showed that one item failed to load clearly on the hypothesized factor (guilt). Once it was removed, results supported the hypothesized four-factor structure. Evidence of invariance of the four-factor structure across sex was obtained. Scores on the BASES showed adequate internal consistency and acceptable convergent validity. Compared to men, women reported significantly higher body and appearance-related guilt and shame, and significant lower authentic and hubristic pride. Preliminary evidence supporting the validity and reliability of the Spanish translation of the BASES is provided. Copyright © 2018 Elsevier Ltd. All rights reserved.
André, Nathalie; Dishman, Rod K
2012-04-01
Exercise adherence involves a number of sociocognitive factors that influence the adoption and maintenance of regular physical activity. Among trait-like factors, self-motivation is believed to be a unique predictor of persistence during behavior change. The aim of this study was to validate the factor structure of a French version of the Self-Motivation Inventory (SMI) and to provide initial convergent and discriminant evidence for its construct validity as a correlate of exercise adherence. Four hundred seventy-one elderly were recruited and administered the SMI-10. Structural equation modeling tested the relation of SMI-10 scores with exercise adherence in a correlated network that included decisional balance and perceived quality of life. Acceptable evidence was found to support the factor validity and measurement equivalence of the French version of the SMI-10. Moreover, self-motivation was related to exercise adherence independently of decisional balance and perceived quality of life, providing initial evidence for construct validity.
Selective Mutism Questionnaire: measurement structure and validity.
Letamendi, Andrea M; Chavira, Denise A; Hitchcock, Carla A; Roesch, Scott C; Shipon-Blum, Elisa; Stein, Murray B
2008-10-01
To evaluate the factor structure, reliability, and validity of the 17-item Selective Mutism Questionnaire (SMQ). Diagnostic interviews were administered via telephone to 102 parents of children identified with selective mutism (SM) and 43 parents of children without SM from varying U.S. geographic regions. Children were between the ages of 3 and 11 inclusive and comprised 58% girls and 42% boys. SM diagnoses were determined using the Anxiety Disorders Interview Schedule for Children-Parent Version; SM severity was assessed using the 17-item SMQ; and behavioral and affective symptoms were assessed using the Child Behavior Checklist. An exploratory factor analysis was conducted to investigate the dimensionality of the SMQ and a modified parallel analysis procedure was used to confirm exploratory factor analysis results. Internal consistency, construct validity, and incremental validity were also examined. The exploratory factor analysis yielded a 13-item solution consisting of three factors: social situations outside of school, school situations, and home and family situations. Internal consistency of SMQ factors and total scale ranged from moderate to high. Convergent and incremental validity was also well supported. Measure structure findings are consistent with the three-factor solution found in a previous psychometric evaluation of the SMQ. Results also suggest that the SMQ provides useful and unique information in the prediction of SM phenomena beyond other child anxiety measures.
Testing comparison models of DASS-12 and its reliability among adolescents in Malaysia.
Osman, Zubaidah Jamil; Mukhtar, Firdaus; Hashim, Hairul Anuar; Abdul Latiff, Latiffah; Mohd Sidik, Sherina; Awang, Hamidin; Ibrahim, Normala; Abdul Rahman, Hejar; Ismail, Siti Irma Fadhilah; Ibrahim, Faisal; Tajik, Esra; Othman, Norlijah
2014-10-01
The 21-item Depression, Anxiety and Stress Scale (DASS-21) is frequently used in non-clinical research to measure mental health factors among adults. However, previous studies have concluded that the 21 items are not stable for utilization among the adolescent population. Thus, the aims of this study are to examine the structure of the factors and to report on the reliability of the refined version of the DASS that consists of 12 items. A total of 2850 students (aged 13 to 17 years old) from three major ethnic in Malaysia completed the DASS-21. The study was conducted at 10 randomly selected secondary schools in the northern state of Peninsular Malaysia. The study population comprised secondary school students (Forms 1, 2 and 4) from the selected schools. Based on the results of the EFA stage, 12 items were included in a final CFA to test the fit of the model. Using maximum likelihood procedures to estimate the model, the selected fit indices indicated a close model fit (χ(2)=132.94, df=57, p=.000; CFI=.96; RMR=.02; RMSEA=.04). Moreover, significant loadings of all the unstandardized regression weights implied an acceptable convergent validity. Besides the convergent validity of the item, a discriminant validity of the subscales was also evident from the moderate latent factor inter-correlations, which ranged from .62 to .75. The subscale reliability was further estimated using Cronbach's alpha and the adequate reliability of the subscales was obtained (Total=76; Depression=.68; Anxiety=.53; Stress=.52). The new version of the 12-item DASS for adolescents in Malaysia (DASS-12) is reliable and has a stable factor structure, and thus it is a useful instrument for distinguishing between depression, anxiety and stress. Copyright © 2014 Elsevier Inc. All rights reserved.
Structural and Convergent Validity of the Homework Performance Questionnaire
ERIC Educational Resources Information Center
Pendergast, Laura L.; Watkins, Marley W.; Canivez, Gary L.
2014-01-01
Homework is a requirement for most school-age children, but research on the benefits and drawbacks of homework is limited by lack of psychometrically sound measurement of homework performance. This study examined the structural and convergent validity of scores from the newly developed Homework Performance Questionnaire -- Teacher Scale (HPQ-T).…
Tobias, Joseph A; Seddon, Nathalie
2009-12-01
Natural selection is known to produce convergent phenotypes through mimicry or ecological adaptation. It has also been proposed that social selection--i.e., selection exerted by social competition--may drive convergent evolution in signals mediating interspecific communication, yet this idea remains controversial. Here, we use color spectrophotometry, acoustic analyses, and playback experiments to assess the hypothesis of adaptive signal convergence in two competing nonsister taxa, Hypocnemis peruviana and H. subflava (Aves: Thamnophilidae). We show that the structure of territorial songs in males overlaps in sympatry, with some evidence of convergent character displacement. Conversely, nonterritorial vocal and visual signals in males are strikingly diagnostic, in line with 6.8% divergence in mtDNA sequences. The same pattern of variation applies to females. Finally, we show that songs in both sexes elicit strong territorial responses within and between species, whereas songs of a third, allopatric and more closely related species (H. striata) are structurally divergent and elicit weaker responses. Taken together, our results provide compelling evidence that social selection can act across species boundaries to drive convergent or parallel evolution in taxa competing for space and resources.
Lucena-Santos, Paola; Trindade, Inês A; Oliveira, Margareth; Pinto-Gouveia, José
2017-05-19
Given the clinical usefulness of the CFQ-BI (Cognitive Fusion Questionnaire-Body Image; the only existing measure to assess the body-image-related cognitive fusion), the present study aimed to confirm its one-factor structure, to verify its measurement invariance between clinical and non-clinical samples, to analyze its internal consistency and sensitivity to detect differences between samples, as well as to explore the incremental and convergent validities of the CFQ-BI scores in Brazilian samples. This was a cross-sectional study, which was conducted in clinical (women with overweight or obesity in treatment for weight loss) and non-clinical samples (women from the general population). The one-factor structure was confirmed showing factorial measurement invariance across clinical and non-clinical samples. The CFQ-BI scores presented an excellent internal consistency, were able to discriminate clinical and non-clinical samples, and were positively associated with binge eating severity, general cognitive fusion, and psychological inflexibility. Furthermore, body-image-related cognitive fusion scores (CFQ-BI) presented incremental validity over a general measure of cognitive fusion in the prediction of binge eating symptoms. This study demonstrated that CFQ-BI is a short scale with reliable and robust scores in Brazilian samples, presenting incremental and convergent validities, measurement invariance, and sensitivity to detect differences between clinical and non-clinical groups of women, enabling comparative studies between them.
Neurobiological Risk Factors for Suicide Insights from Brain Imaging
Cox Lippard, Elizabeth T.; Johnston, Jennifer A.Y.; Blumberg, Hilary P.
2014-01-01
Context This article reviews neuroimaging studies on neural circuitry associated with suicide-related thoughts and behaviors to identify areas of convergence in findings. Gaps in the literature for which additional research is needed are identified. Evidence acquisition A PubMed search was conducted and articles published prior to March 2014 were reviewed that compared individuals who made suicide attempts to those with similar diagnoses who had not made attempts or to healthy comparison subjects. Articles on adults with suicidal ideation and adolescents who had made attempts, or with suicidal ideation, were also included. Reviewed imaging modalities included structural magnetic resonance imaging, diffusion tensor imaging, single photon emission computerized tomography, positron emission tomography, and functional magnetic resonance imaging. Evidence synthesis Although many studies include small samples, and subject characteristics and imaging methods vary across studies, there were convergent findings involving the structure and function of frontal neural systems and the serotonergic system. Conclusions These initial neuroimaging studies of suicide behavior have provided promising results. Future neuroimaging efforts could be strengthened by more strategic use of common data elements, and a focus on suicide risk trajectories. At-risk subgroups defined by biopsychosocial risk factors and multidimensional assessment of suicidal thoughts and behaviors may provide a clearer picture of the neural circuitry associated with risk status—both current and lifetime. Also needed are studies investigating neural changes associated with interventions that are effective in risk reduction. PMID:25145733
Convergence of an iterative procedure for large-scale static analysis of structural components
NASA Technical Reports Server (NTRS)
Austin, F.; Ojalvo, I. U.
1976-01-01
The paper proves convergence of an iterative procedure for calculating the deflections of built-up component structures which can be represented as consisting of a dominant, relatively stiff primary structure and a less stiff secondary structure, which may be composed of one or more substructures that are not connected to one another but are all connected to the primary structure. The iteration consists in estimating the deformation of the primary structure in the absence of the secondary structure on the assumption that all mechanical loads are applied directly to the primary structure. The j-th iterate primary structure deflections at the interface are imposed on the secondary structure, and the boundary loads required to produce these deflections are computed. The cycle is completed by applying the interface reaction to the primary structure and computing its updated deflections. It is shown that the mathematical condition for convergence of this procedure is that the maximum eigenvalue of the equation relating primary-structure deflection to imposed secondary-structure deflection be less than unity, which is shown to correspond with the physical requirement that the secondary structure be more flexible at the interface boundary.
Evolution and convergence of the patterns of international scientific collaboration.
Coccia, Mario; Wang, Lili
2016-02-23
International research collaboration plays an important role in the social construction and evolution of science. Studies of science increasingly analyze international collaboration across multiple organizations for its impetus in improving research quality, advancing efficiency of the scientific production, and fostering breakthroughs in a shorter time. However, long-run patterns of international research collaboration across scientific fields and their structural changes over time are hardly known. Here we show the convergence of international scientific collaboration across research fields over time. Our study uses a dataset by the National Science Foundation and computes the fraction of papers that have international institutional coauthorships for various fields of science. We compare our results with pioneering studies carried out in the 1970s and 1990s by applying a standardization method that transforms all fractions of internationally coauthored papers into a comparable framework. We find, over 1973-2012, that the evolution of collaboration patterns across scientific disciplines seems to generate a convergence between applied and basic sciences. We also show that the general architecture of international scientific collaboration, based on the ranking of fractions of international coauthorships for different scientific fields per year, has tended to be unchanged over time, at least until now. Overall, this study shows, to our knowledge for the first time, the evolution of the patterns of international scientific collaboration starting from initial results described by literature in the 1970s and 1990s. We find a convergence of these long-run collaboration patterns between the applied and basic sciences. This convergence might be one of contributing factors that supports the evolution of modern scientific fields.
Non-Rigid Structure Estimation in Trajectory Space from Monocular Vision
Wang, Yaming; Tong, Lingling; Jiang, Mingfeng; Zheng, Junbao
2015-01-01
In this paper, the problem of non-rigid structure estimation in trajectory space from monocular vision is investigated. Similar to the Point Trajectory Approach (PTA), based on characteristic points’ trajectories described by a predefined Discrete Cosine Transform (DCT) basis, the structure matrix was also calculated by using a factorization method. To further optimize the non-rigid structure estimation from monocular vision, the rank minimization problem about structure matrix is proposed to implement the non-rigid structure estimation by introducing the basic low-rank condition. Moreover, the Accelerated Proximal Gradient (APG) algorithm is proposed to solve the rank minimization problem, and the initial structure matrix calculated by the PTA method is optimized. The APG algorithm can converge to efficient solutions quickly and lessen the reconstruction error obviously. The reconstruction results of real image sequences indicate that the proposed approach runs reliably, and effectively improves the accuracy of non-rigid structure estimation from monocular vision. PMID:26473863
Psychometric properties of the Turkish version of the Internet Addiction Test (IAT).
Boysan, Murat; Kuss, Daria J; Barut, Yaşar; Ayköse, Nafi; Güleç, Mustafa; Özdemir, Osman
2017-01-01
Of many instruments developed to assess Internet addiction, the Internet Addiction Test (IAT), an expanded version of the Internet Addiction Diagnostic Questionnaire (IADQ), has been the most widely used scale in English and non-English speaking populations. In this study, our aim was to investigate the psychometric properties of short and expanded versions of the IAT in a Turkish undergraduate sample. Overall, 455 undergraduate students from Turkey aged between 18 and 30 participated in the study (63.53% were females). Explanatory and confirmatory factor analytic procedures investigated factor structures of the IADQ and IAT. The Internet Addiction Scale (IAS), Coping Inventory for Stressful Situations (CISS), Obsessive Compulsive Inventory-Revised (OCI-R) and Dissociative Experiences Scale (DES) were administered to assess convergent and divergent validities of the IADQ and IAT. Internal consistency and 15-day test-retest reliability were computed. In the factorial analytic investigation, we found a unidimensional factor structure for each measure fit the current data best. Significant but weak to moderate correlations of the IADQ and the IAT with the CISS, OCI-R and DES provided empirical evidence for divergent validity, whereas strong associations with the subscales of the IAS pointed to the convergent validity of Young's Internet addiction construct. Internal consistency of the IADQ was weak (α=0.67) and of the IAT was high (α=0.93). Temporal reliability of both instruments was very high (α=0.81 and α=0.87; respectively). The IAT revealed promising and sound psychometric properties in a Turkish sample. Copyright © 2015 Elsevier Ltd. All rights reserved.
Jurk, Sarah; Kuitunen-Paul, Sören; Kroemer, Nils B; Artiges, Eric; Banaschewski, Tobias; Bokde, Arun L W; Büchel, Christian; Conrod, Patricia; Fauth-Bühler, Mira; Flor, Herta; Frouin, Vincent; Gallinat, Jürgen; Garavan, Hugh; Heinz, Andreas; Mann, Karl F; Nees, Frauke; Paus, Tomáš; Pausova, Zdenka; Poustka, Luise; Rietschel, Marcella; Schumann, Gunter; Struve, Maren; Smolka, Michael N
2015-11-01
The aim of the present longitudinal study was the psychometric evaluation of the Substance Use Risk Profile Scale (SURPS). We analyzed data from N = 2,022 adolescents aged 13 to 15 at baseline assessment and 2 years later (mean interval 2.11 years). Missing data at follow-up were imputed (N = 522). Psychometric properties of the SURPS were analyzed using confirmatory factor analysis. We examined structural as well as convergent validity with other personality measurements and drinking motives, and predictive validity for substance use at follow-up. The hypothesized 4-factorial structure (i.e., anxiety sensitivity, hopelessness, impulsivity [IMP], and sensation seeking [SS]) based on all 23 items resulted in acceptable fit to empirical data, acceptable internal consistencies, low to moderate test-retest reliability coefficients, as well as evidence for factorial and convergent validity. The proposed factor structure was stable for both males and females and, to lesser degree, across languages. However, only the SS and the IMP subscales of the SURPS predicted substance use outcomes at 16 years of age. The SURPS is unique in its specific assessment of traits related to substance use disorders as well as the resulting shortened administration time. Test-retest reliability was low to moderate and comparable to other personality scales. However, its relation to future substance use was limited to the SS and IMP subscales, which may be due to the relatively low-risk substance use pattern in the present sample. Copyright © 2015 by the Research Society on Alcoholism.
Heesy, Christopher P
2008-01-01
Primates are characterized by forward-facing, or convergent, orbits and associated binocular field overlap. Hypotheses explaining the adaptive significance of these traits often relate to ecological factors, such as arboreality, nocturnal visual predation, or saltatory locomotion in a complex nocturnal, arboreal environment. This study re-examines the ecological factors that are associated with high orbit convergence in mammals. Orbit orientation data were collected for 321 extant taxa from sixteen orders of metatherian (marsupial) and eutherian mammals. These taxa were coded for activity pattern, degree of faunivory, and substrate preference. Results demonstrate that nocturnal and cathemeral mammals have significantly more convergent orbits than diurnal taxa, both within and across orders. Faunivorous eutherians (both nocturnal and diurnal) have higher mean orbit convergence than opportunistically foraging or non-faunivorous taxa. However, substrate preference is not associated with higher orbit convergence and, by extension, greater binocular visual field overlap. These results are consistent with the hypothesis that mammalian predators evolved higher orbit convergence, binocular vision, and stereopsis to counter camouflage in prey inhabiting a nocturnal environment. Strepsirhine primates have a range of orbit convergence values similar to nocturnal or cathemeral predatory non-primate mammals. These data are entirely consistent with the nocturnal visual predation hypothesis of primate origins. (c) 2007 S. Karger AG, Basel.
John, Christopher R.; Smith-Unna, Richard D.; Woodfield, Helen; Covshoff, Sarah; Hibberd, Julian M.
2014-01-01
Leaves of almost all C4 lineages separate the reactions of photosynthesis into the mesophyll (M) and bundle sheath (BS). The extent to which messenger RNA profiles of M and BS cells from independent C4 lineages resemble each other is not known. To address this, we conducted deep sequencing of RNA isolated from the M and BS of Setaria viridis and compared these data with publicly available information from maize (Zea mays). This revealed a high correlation (r = 0.89) between the relative abundance of transcripts encoding proteins of the core C4 pathway in M and BS cells in these species, indicating significant convergence in transcript accumulation in these evolutionarily independent C4 lineages. We also found that the vast majority of genes encoding proteins of the C4 cycle in S. viridis are syntenic to homologs used by maize. In both lineages, 122 and 212 homologous transcription factors were preferentially expressed in the M and BS, respectively. Sixteen shared regulators of chloroplast biogenesis were identified, 14 of which were syntenic homologs in maize and S. viridis. In sorghum (Sorghum bicolor), a third C4 grass, we found that 82% of these trans-factors were also differentially expressed in either M or BS cells. Taken together, these data provide, to our knowledge, the first quantification of convergence in transcript abundance in the M and BS cells from independent lineages of C4 grasses. Furthermore, the repeated recruitment of syntenic homologs from large gene families strongly implies that parallel evolution of both structural genes and trans-factors underpins the polyphyletic evolution of this highly complex trait in the monocotyledons. PMID:24676859
Validity and Reliability of the 8-Item Work Limitations Questionnaire.
Walker, Timothy J; Tullar, Jessica M; Diamond, Pamela M; Kohl, Harold W; Amick, Benjamin C
2017-12-01
Purpose To evaluate factorial validity, scale reliability, test-retest reliability, convergent validity, and discriminant validity of the 8-item Work Limitations Questionnaire (WLQ) among employees from a public university system. Methods A secondary analysis using de-identified data from employees who completed an annual Health Assessment between the years 2009-2015 tested research aims. Confirmatory factor analysis (CFA) (n = 10,165) tested the latent structure of the 8-item WLQ. Scale reliability was determined using a CFA-based approach while test-retest reliability was determined using the intraclass correlation coefficient. Convergent/discriminant validity was tested by evaluating relations between the 8-item WLQ with health/performance variables for convergent validity (health-related work performance, number of chronic conditions, and general health) and demographic variables for discriminant validity (gender and institution type). Results A 1-factor model with three correlated residuals demonstrated excellent model fit (CFI = 0.99, TLI = 0.99, RMSEA = 0.03, and SRMR = 0.01). The scale reliability was acceptable (0.69, 95% CI 0.68-0.70) and the test-retest reliability was very good (ICC = 0.78). Low-to-moderate associations were observed between the 8-item WLQ and the health/performance variables while weak associations were observed between the demographic variables. Conclusions The 8-item WLQ demonstrated sufficient reliability and validity among employees from a public university system. Results suggest the 8-item WLQ is a usable alternative for studies when the more comprehensive 25-item WLQ is not available.
Ezra Zemach
2010-01-01
Multiple data sets converge on a geologic structural model for Glass Buttes, Oregon geothermal prospect, Patrick Walsh, Brigette Martini, Chet Lide, Darrick Boschmann, John DIlles, Andrew Meigs, 2010 Ormat Nevada, Zonge Geophysical, Oregon State University American Geophysical Union, Poster Session
The convergence of health care financing structures: empirical evidence from OECD-countries.
Leiter, Andrea M; Theurl, Engelbert
2012-02-01
The convergence/divergence of health care systems between countries is an interesting facet of the health care system research from a macroeconomic perspective. In this paper, we concentrate on an important dimension of every health care system, namely the convergence/divergence of health care financing (HCF). Based on data from 22 OECD countries in the time period 1970-2005, we use the public financing ratio (public financing in % of total HCF) and per capita public HCF as indicators for convergence. By applying different concepts of convergence, we find that HCF is converging. This conclusion also holds when we look at smaller subgroups of countries and shorter time periods. However, we find evidence that countries do not move towards a common mean and that the rate of convergence is decreasing over time.
Stochastic model of cell rearrangements in convergent extension of ascidian notochord
NASA Astrophysics Data System (ADS)
Lubkin, Sharon; Backes, Tracy; Latterman, Russell; Small, Stephen
2007-03-01
We present a discrete stochastic cell based model of convergent extension of the ascidian notochord. Our work derives from research that clarifies the coupling of invagination and convergent extension in ascidian notochord morphogenesis (Odell and Munro, 2002). We have tested the roles of cell-cell adhesion, cell-extracellular matrix adhesion, random motion, and extension of individual cells, as well as the presence or absence of various tissue types, and determined which factors are necessary and/or sufficient for convergent extension.
Yokokura, Ana Valéria Carvalho Pires; Silva, Antônio Augusto Moura da; Fernandes, Juliana de Kássia Braga; Del-Ben, Cristina Marta; Figueiredo, Felipe Pinheiro de; Barbieri, Marco Antonio; Bettiol, Heloisa
2017-12-18
This study aimed to assess the dimensional structure, reliability, convergent validity, discriminant validity, and scalability of the Perceived Stress Scale (PSS). The sample consisted of 1,447 pregnant women in São Luís (Maranhão State) and 1,400 in Ribeirão Preto (São Paulo State), Brazil. The 14 and 10-item versions of the scale were assessed using confirmatory factor analysis, using weighted least squares means and variance (WLSMV). In both cities, the two-factor models (positive factors, measuring resilience to stressful situations, and negative factors, measuring stressful situations) showed better fit than the single-factor models. The two-factor models for the complete (PSS14) and reduced scale (PSS10) showed good internal consistency (Cronbach's alpha ≥ 0.70). All the factor loadings were ≥ 0.50, except for items 8 and 12 of the negative dimension and item 13 of the positive dimension. The correlations between both dimensions of stress and psychological violence showed the expected magnitude (0.46-0.59), providing evidence of an adequate convergent construct validity. The correlations between the scales' positive and negative dimensions were around 0.74-0.78, less than 0.85, which suggests adequate discriminant validity. Extracted mean variance and scalability were slightly higher for PSS10 than for PSS14. The results were consistent in both cities. In conclusion, the single-factor solution is not recommended for assessing stress in pregnant women. The reduced, 10-item two-factor scale appears to be more appropriate for measuring perceived stress in pregnant women.
Self-similar dynamic converging shocks - I. An isothermal gas sphere with self-gravity
NASA Astrophysics Data System (ADS)
Lou, Yu-Qing; Shi, Chun-Hui
2014-07-01
We explore novel self-similar dynamic evolution of converging spherical shocks in a self-gravitating isothermal gas under conceivable astrophysical situations. The construction of such converging shocks involves a time-reversal operation on feasible flow profiles in self-similar expansion with a proper care for the increasing direction of the specific entropy. Pioneered by Guderley since 1942 but without self-gravity so far, self-similar converging shocks are important for implosion processes in aerodynamics, combustion, and inertial fusion. Self-gravity necessarily plays a key role for grossly spherical structures in very broad contexts of astrophysics and cosmology, such as planets, stars, molecular clouds (cores), compact objects, planetary nebulae, supernovae, gamma-ray bursts, supernova remnants, globular clusters, galactic bulges, elliptical galaxies, clusters of galaxies as well as relatively hollow cavity or bubble structures on diverse spatial and temporal scales. Large-scale dynamic flows associated with such quasi-spherical systems (including collapses, accretions, fall-backs, winds and outflows, explosions, etc.) in their initiation, formation, and evolution are likely encounter converging spherical shocks at times. Our formalism lays an important theoretical basis for pertinent astrophysical and cosmological applications of various converging shock solutions and for developing and calibrating numerical codes. As examples, we describe converging shock triggered star formation, supernova explosions, and void collapses.
de Medeiros, Anna Cecília Queiroz; Yamamoto, Maria Emilia; Pedrosa, Lucia Fatima Campos; Hutz, Claudio Simon
2017-03-01
This study aimed to evaluate the psychometric properties and scoring pattern of the Brazilian version of the three-factor eating questionnaire-r21 (TFEQ-R21). Data were collected from 410 undergraduate students. Confirmatory factor analysis was conducted to examine the factor structure of the TFEQ-R21. Convergent and discriminant validity also was assessed. Cluster analysis was performed to investigate scoring patterns. In assessing the quality setting, the model was considered satisfactory (χ 2 /gl = 2.24, CFI = 0.97, TLI = 0.96, RMSEA = 0.05). The instrument was also considered appropriate in relation to the discriminant and convergent validity. There was a positive correlation between body mass index and the dimensions of cognitive restraint (r s = 0.449, p < 0.001) and emotional eating (r s = 0.112, p = 0.023). Using cluster analysis three respondent profiles were identified. The profile "A" was associated with appropriate weight, the "B" was characterized by high scores in cognitive restraint dimension, and the cluster "C" focused individuals who had higher scores on the uncontrolled eating and emotional eating dimensions. The Brazilian version of TFEQ-R21 has adequate psychometric properties, and the identified response profiles offer a promising prospect for its use in clinical practice, in weight loss interventions.
Corr, Philip J; Cooper, Andrew J
2016-11-01
We report the development and validation of a questionnaire measure of the revised reinforcement sensitivity theory (rRST) of personality. Starting with qualitative responses to defensive and approach scenarios modeled on typical rodent ethoexperimental situations, exploratory and confirmatory factor analyses (CFAs) revealed a robust 6-factor structure: 2 unitary defensive factors, fight-flight-freeze system (FFFS; related to fear) and the behavioral inhibition system (BIS; related to anxiety); and 4 behavioral approach system (BAS) factors (Reward Interest, Goal-Drive Persistence, Reward Reactivity, and Impulsivity). Theoretically motivated thematic facets were employed to sample the breadth of defensive space, comprising FFFS (Flight, Freeze, and Active Avoidance) and BIS (Motor Planning Interruption, Worry, Obsessive Thoughts, and Behavioral Disengagement). Based on theoretical considerations, and statistically confirmed, a separate scale for Defensive Fight was developed. Validation evidence for the 6-factor structure came from convergent and discriminant validity shown by correlations with existing personality scales. We offer the Reinforcement Sensitivity Theory of Personality Questionnaire to facilitate future research specifically on rRST and, more broadly, on approach-avoidance theories of personality. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Attitude Toward Ambiguity: Empirically Robust Factors in Self-Report Personality Scales.
Lauriola, Marco; Foschi, Renato; Mosca, Oriana; Weller, Joshua
2016-06-01
Two studies were conducted to examine the factor structure of attitude toward ambiguity, a broad personality construct that refers to personal reactions to perceived ambiguous stimuli in a variety of context and situations. Using samples from two countries, Study 1 mapped the hierarchical structure of 133 items from seven tolerance-intolerance of ambiguity scales (N = 360, Italy; N = 306, United States). Three major factors-Discomfort with Ambiguity, Moral Absolutism/Splitting, and Need for Complexity and Novelty-were recovered in each country with high replicability coefficients across samples. In Study 2 (N = 405, Italian community sample; N =366, English native speakers sample), we carried out a confirmatory analysis on selected factor markers. A bifactor model had an acceptable fit for each sample and reached the construct-level invariance for general and group factors. Convergent validity with related traits was assessed in both studies. We conclude that attitude toward ambiguity can be best represented a multidimensional construct involving affective (Discomfort with Ambiguity), cognitive (Moral Absolutism/Splitting), and epistemic (Need for Complexity and Novelty) components. © The Author(s) 2015.
Leading people positively: cross-cultural validation of the Servant Leadership Survey (SLS).
Rodríguez-Carvajal, Raquel; de Rivas, Sara; Herrero, Marta; Moreno-Jiménez, Bernardo; van Dierendonck, Dirk
2014-10-24
Servant Leadership emphasizes employee's development and growth within a context of moral and social concern. Nowadays, this management change towards workers´ wellbeing is highlighted as an important issue. The aims of this paper are to adapt to Spanish speakers the Servant Leadership Survey (SLS) by van Dierendonck and Nuijten (2011), and to analyze its factorial validity through confirmatory factor analysis and measurement invariance in three countries. A sample of 638 working people from three Spanish-speaking countries (Spain, Argentina and Mexico) participated in the study. In all three countries, confirmatory factor analyses corroborate the eight factor structure (empowerment, accountability, standing back, humility, authenticity, courage, forgiveness and stewardship) with one second order factor (servant leadership) (in all three samples, CFI, IFI > .92, TLI > .91, RMSEA < .70). Also, factor loadings, reliability and convergent validity were acceptable across samples. Furthermore, through measurement invariance analysis, we detected model equivalence in all three countries including structural residual invariance (ΔCFI = .001). Finally, cultural differences in some dimensions were found and discussed, opening the way for future cross-cultural studies.
Harlan, E; Clark, L A
1999-06-01
Researchers and clinicians alike increasingly seek brief, reliable, and valid measures to obtain personality trait ratings from both selves and peers. We report the development of a paragraph-descriptor short form of a full-length personality assessment instrument, the Schedule for Nonadaptive and Adaptive Personality (SNAP) with both self- and other versions. Reliability and validity data were collected on a sample of 294 college students, from 90 of whom we also obtained parental ratings of their personality. Internal consistency reliability was good in both self- and parent data. The factorial structures of the self-report short and long forms were very similar. Convergence between parental ratings was moderately high. Self-parent convergence was variable, with lower agreement on scales assessing subjective distress than those assessing more observable behaviors; it also was stronger for higher order factors than for scales.
Kamtsios, Spiridon; Karagiannopoulou, Evangelia
2016-02-01
The purpose of the study was to establish the reliability, the structural and the convergent validity of the "Dimensions of Academic Hardiness Questionnaire" for late elementary school children. A sample of children (N = 1264) aged 10-12 years completed the questionnaire and the "Athens Coping Scale". Multiple fit indices provided support that the 9-factor model had a good fit to the data. Reliability coefficients ranged from .68 to .83. The study provided also preliminary evidence of convergent validity of the "Dimensions of Academic Hardiness" scores with one theoretically related measure, the "Athens Coping Scale". The results enrich the notion of Academic Hardiness in late elementary school children as the role of awareness and the role of children's previous experiences has been distinguished. The relation between the "Dimensions of Academic Hardiness" and achievement goal orientations in children learning is also noted. These findings are discussed in the context of the relevant literature.
Colorado Learning Difficulties Questionnaire:Validation of a parent-report screening measure
Willcutt, Erik G.; Boada, Richard; Riddle, Margaret W.; Chhabildas, Nomita; DeFries, John C.; Pennington, Bruce F.
2011-01-01
This study evaluated the internal structure and convergent and discriminant evidence for the Colorado Learning Difficulties Questionnaire (CLDQ), a 20-item parent-report rating scale that was developed to provide a brief screening measure for learning difficulties. CLDQ ratings were obtained from parents of children in two large community samples and two samples from clinics that specialize in the assessment of learning disabilities and related disorders (total N = 8,004). Exploratory and confirmatory factor analyses revealed five correlated but separable dimensions that were labeled reading, math, social cognition, social anxiety, and spatial difficulties. Results revealed strong convergent and discriminant evidence for the CLDQ Reading scale, suggesting that this scale may provide a useful method to screen for reading difficulties in both research studies and clinical settings. Results are also promising for the other four CLDQ scales, but additional research is needed to refine each of these measures. PMID:21574721
Mapping the MMPI-2-RF Specific Problems Scales Onto Extant Psychopathology Structures.
Sellbom, Martin
2017-01-01
A main objective in developing the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF; Ben-Porath & Tellegen, 2008 ) was to link the hierarchical structure of the instrument's scales to contemporary psychopathology and personality models for greater enhancement of construct validity. Initial evidence published with the Restructured Clinical scales has indicated promising results in that the higher order structure of these measures maps onto those reported in the extant psychopathology literature. This study focused on evaluating the internal structure of the Specific Problems and Interest scales, which have not yet been examined in this manner. Two large, mixed-gender outpatient and correctional samples were used. Exploratory factor analyses revealed consistent evidence for a 4-factor structure representing somatization, negative affect, externalizing, and social detachment. Convergent and discriminant validity analyses in the outpatient sample yielded a pattern of results consistent with expectations. These findings add further evidence to indicate that the MMPI-2-RF hierarchy of scales map onto extant psychopathology literature, and also add support to the notion that somatization and detachment should be considered important higher order domains in the psychopathology literature.
Examination of a Bifactor Model of Obsessive-Compulsive Symptom Dimensions.
Olatunji, Bunmi O; Ebesutani, Chad; Abramowitz, Jonathan S
2017-01-01
Although obsessive-compulsive (OC) symptoms are observed along four dimensions (contamination, responsibility for harm, order/symmetry, and unacceptable thoughts), the structure of the dimensions remains unclear. The current study evaluated a bifactor model of OC symptoms among those with and without obsessive-compulsive disorder (OCD). The goals were (a) to evaluate if OC symptoms should be conceptualized as unidimensional or whether distinct dimensions should be interpreted and (b) to use structural equation modeling to examine the convergence of the OC dimensions above and beyond a general dimension with related criteria. Results revealed that a bifactor model fit the data well and that OC symptoms were influenced by a general dimension and by four dimensions. Measurement invariance of the bifactor model was also supported among those with and without OCD. However, the general OC dimension accounted for only half of the variability in OC symptoms, with the remaining variability accounted for by distinct dimensions. Despite evidence of multidimensionality, the dimensions were unreliable after covarying for the general OC dimension. However, the four dimensions did significantly converge with a latent OC spectrum factor above and beyond the general OC dimension. The implications of these findings for conceptualizing the structure of OCD are discussed. © The Author(s) 2015.
Factorization of laser-pulse ionization probabilities in the multiphotonic regime
NASA Astrophysics Data System (ADS)
Della Picca, R.; Fiol, J.; Fainstein, P. D.
2013-09-01
We present a detailed study of the ionization probability of H and H_{2}^{+} induced by a short intense laser pulse. Starting from a Coulomb-Volkov description of the process we derive a multipole-like expansion where each term is factored into two contributions: one that accounts for the effect of the electromagnetic field on the free-electron final state and a second factor that depends only on the target structure. Such a separation may be valuable to solve complex atomic or molecular systems as well as to interpret the dynamics of the process in simpler terms. We show that the series expansion converges rapidly, and thus the inclusion of the first few terms is sufficient to produce accurate results.
Warren, Janet I; South, Susan C
2009-01-01
The psychometric properties and structure of the Cluster B Personality Disorder criteria (Antisocial, Borderline, Histrionic, and Narcissistic) are examined in a sample of 261 female inmates using a self-report screen followed by a full diagnostic interview. The results of the structural analyses in this sample demonstrated good internal consistency and convergence, but poor discriminant validity between disorders. An exploratory factor analysis found that the structure of these disorders was best accounted for by a four-factor solution that paralleled the Diagnostic and Statistical Manual (DSM-IV-TR; APA, 2000) classification scheme with some significant and notable exceptions. Using the factor scores generated from the factor analysis, the personality profiles of the women were compared with several behavioral indices, including instant offense, institutional infractions, and self-report violence and victimization within the prison. Of particular importance was the consistent relationship observed between narcissistic personality traits and threatening and violent behavior within the prison combined with the impulsive but less malignant presentation of antisocial personality traits among this sample of women. Results are discussed as they inform our understanding of the structural integrity of the four Cluster B diagnostic categories and the relationship of these personality disorders to different types of criminality and violence.
Wolf, Pedro S A; Figueredo, Aurelio J; Jacobs, W Jake
2013-01-01
The purpose of this paper is to examine the convergent and nomological validity of a GPS-based measure of daily activity, operationalized as Number of Places Visited (NPV). Relations among the GPS-based measure and two self-report measures of NPV, as well as relations among NPV and two factors made up of self-reported individual differences were examined. The first factor was composed of variables related to an Active Lifestyle (AL) (e.g., positive affect, extraversion…) and the second factor was composed of variables related to a Sedentary Lifestyle (SL) (e.g., depression, neuroticism…). NPV was measured over 4 days. This timeframe was made up of two week and two weekend days. A bi-variate analysis established one level of convergent validity and a Split-Plot GLM examined convergent validity, nomological validity, and alternative hypotheses related to constraints on activity throughout the week simultaneously. The first analysis revealed significant correlations among NPV measures- weekday, weekend, and the entire 4-day time period, supporting the convergent validity of the Diary-, Google Maps-, and GPS-NPV measures. Results from the second analysis, indicating non-significant mean differences in NPV regardless of method, also support this conclusion. We also found that AL is a statistically significant predictor of NPV no matter how NPV was measured. We did not find a statically significant relation among NPV and SL. These results permit us to infer that the GPS-based NPV measure has convergent and nomological validity.
Wolf, Pedro S. A.; Figueredo, Aurelio J.; Jacobs, W. Jake
2013-01-01
The purpose of this paper is to examine the convergent and nomological validity of a GPS-based measure of daily activity, operationalized as Number of Places Visited (NPV). Relations among the GPS-based measure and two self-report measures of NPV, as well as relations among NPV and two factors made up of self-reported individual differences were examined. The first factor was composed of variables related to an Active Lifestyle (AL) (e.g., positive affect, extraversion…) and the second factor was composed of variables related to a Sedentary Lifestyle (SL) (e.g., depression, neuroticism…). NPV was measured over 4 days. This timeframe was made up of two week and two weekend days. A bi-variate analysis established one level of convergent validity and a Split-Plot GLM examined convergent validity, nomological validity, and alternative hypotheses related to constraints on activity throughout the week simultaneously. The first analysis revealed significant correlations among NPV measures- weekday, weekend, and the entire 4-day time period, supporting the convergent validity of the Diary-, Google Maps-, and GPS-NPV measures. Results from the second analysis, indicating non-significant mean differences in NPV regardless of method, also support this conclusion. We also found that AL is a statistically significant predictor of NPV no matter how NPV was measured. We did not find a statically significant relation among NPV and SL. These results permit us to infer that the GPS-based NPV measure has convergent and nomological validity. PMID:23761772
Feelings about culture scales: development, factor structure, reliability, and validity.
Maffini, Cara S; Wong, Y Joel
2015-04-01
Although measures of cultural identity, values, and behavior exist in the multicultural psychological literature, there is currently no measure that explicitly assesses ethnic minority individuals' positive and negative affect toward culture. Therefore, we developed 2 new measures called the Feelings About Culture Scale--Ethnic Culture and Feelings About Culture Scale--Mainstream American Culture and tested their psychometric properties. In 6 studies, we piloted the measures, conducted factor analyses to clarify their factor structure, and examined reliability and validity. The factor structure revealed 2 dimensions reflecting positive and negative affect for each measure. Results provided evidence for convergent, discriminant, criterion-related, and incremental validity as well as the reliability of the scales. The Feelings About Culture Scales are the first known measures to examine both positive and negative affect toward an individual's ethnic culture and mainstream American culture. The focus on affect captures dimensions of psychological experiences that differ from cognitive and behavioral constructs often used to measure cultural orientation. These measures can serve as a valuable contribution to both research and counseling by providing insight into the nuanced affective experiences ethnic minority individuals have toward culture. (c) 2015 APA, all rights reserved).
General cognitive principles for learning structure in time and space.
Goldstein, Michael H; Waterfall, Heidi R; Lotem, Arnon; Halpern, Joseph Y; Schwade, Jennifer A; Onnis, Luca; Edelman, Shimon
2010-06-01
How are hierarchically structured sequences of objects, events or actions learned from experience and represented in the brain? When several streams of regularities present themselves, which will be learned and which ignored? Can statistical regularities take effect on their own, or are additional factors such as behavioral outcomes expected to influence statistical learning? Answers to these questions are starting to emerge through a convergence of findings from naturalistic observations, behavioral experiments, neurobiological studies, and computational analyses and simulations. We propose that a small set of principles are at work in every situation that involves learning of structure from patterns of experience and outline a general framework that accounts for such learning. (c) 2010 Elsevier Ltd. All rights reserved.
Tsuchiyagaito, Aki; Horiuchi, Satoshi; Igarashi, Toko; Kawanori, Yoshiya; Hirano, Yoshiyuki; Yabe, Hirooki; Nakagawa, Akiko
2017-01-01
The Hoarding Rating Scale-Self-Report (HRS-SR) is a five-item scale that assesses the symptoms of hoarding. These symptoms include excessive acquisition, difficulty in discarding, and excessive clutter that causes distress. We conducted three studies to examine the factor structure, reliability, and validity of the Japanese version of the HRS-SR (HRS-SR-J). Study 1 examined its reliability; 193 college students and 320 adolescents and adults completed the HRS-SR-J and, of the college students, 32 took it again 2 weeks later. Study 2 aimed to confirm that its scores in a sample of 210 adolescents and adults are independent of social desirability. Study 3 aimed to validate the HRS-SR-J in the aspects of convergent and discriminant validity in a sample of 550 adults. The HRS-SR-J showed good internal consistency and 2-week test-retest reliability. Based on the nonsignificant correlations between the HRS-SR-J and social desirability, the HRS-SR-J was not strongly affected by social desirability. In addition, it also had a good convergent validity with the Japanese version of the Saving Inventory-Revised (SI-R-J) and the hoarding subscale of the Obsessive-Compulsive Inventory, while having a significantly weaker correlation with the five subscales of the Obsessive-Compulsive Inventory, except for the hoarding subscale. In addition, the strength of the correlation between the HRS-SR-J and the Japanese version of the Patient Health Questionnaire-9 and that between the HRS-SR-J and the Generalized Anxiety Disorder-7 were significantly weaker than the correlation between the HRS-SR-J and the SI-R-J. These results demonstrate that the HRS-SR-J has good convergent and discriminant validity. The HRS-SR-J is a notable self-report scale for examining the severity of hoarding symptoms.
Longest, P Worth; Vinchurkar, Samir
2007-04-01
A number of research studies have employed a wide variety of mesh styles and levels of grid convergence to assess velocity fields and particle deposition patterns in models of branching biological systems. Generating structured meshes based on hexahedral elements requires significant time and effort; however, these meshes are often associated with high quality solutions. Unstructured meshes that employ tetrahedral elements can be constructed much faster but may increase levels of numerical diffusion, especially in tubular flow systems with a primary flow direction. The objective of this study is to better establish the effects of mesh generation techniques and grid convergence on velocity fields and particle deposition patterns in bifurcating respiratory models. In order to achieve this objective, four widely used mesh styles including structured hexahedral, unstructured tetrahedral, flow adaptive tetrahedral, and hybrid grids have been considered for two respiratory airway configurations. Initial particle conditions tested are based on the inlet velocity profile or the local inlet mass flow rate. Accuracy of the simulations has been assessed by comparisons to experimental in vitro data available in the literature for the steady-state velocity field in a single bifurcation model as well as the local particle deposition fraction in a double bifurcation model. Quantitative grid convergence was assessed based on a grid convergence index (GCI), which accounts for the degree of grid refinement. The hexahedral mesh was observed to have GCI values that were an order of magnitude below the unstructured tetrahedral mesh values for all resolutions considered. Moreover, the hexahedral mesh style provided GCI values of approximately 1% and reduced run times by a factor of 3. Based on comparisons to empirical data, it was shown that inlet particle seedings should be consistent with the local inlet mass flow rate. Furthermore, the mesh style was found to have an observable effect on cumulative particle depositions with the hexahedral solution most closely matching empirical results. Future studies are needed to assess other mesh generation options including various forms of the hybrid configuration and unstructured hexahedral meshes.
ERIC Educational Resources Information Center
Nelson, Jason M.; Canivez, Gary L.
2012-01-01
Empirical examination of the Reynolds Intellectual Assessment Scales (RIAS; C. R. Reynolds & R. W. Kamphaus, 2003a) has produced mixed results regarding its internal structure and convergent validity. Various aspects of validity of RIAS scores with a sample (N = 521) of adolescents and adults seeking psychological evaluations at a university-based…
Spirituality as a Scientific Construct: Testing Its Universality across Cultures and Languages
MacDonald, Douglas A.; Friedman, Harris L.; Brewczynski, Jacek; Holland, Daniel; Salagame, Kiran Kumar K.; Mohan, K. Krishna; Gubrij, Zuzana Ondriasova; Cheong, Hye Wook
2015-01-01
Using data obtained from 4004 participants across eight countries (Canada, India, Japan, Korea, Poland, Slovakia, Uganda, and the U.S.), the factorial reliability, validity and structural/measurement invariance of a 30-item version of Expressions of Spirituality Inventory (ESI-R) was evaluated. The ESI-R measures a five factor model of spirituality developed through the conjoint factor analysis of several extant measures of spiritual constructs. Exploratory factor analyses of pooled data provided evidence that the five ESI-R factors are reliable. Confirmatory analyses comparing four and five factor models revealed that the five dimensional model demonstrates superior goodness-of-fit with all cultural samples and suggest that the ESI-R may be viewed as structurally invariant. Measurement invariance, however, was not supported as manifested in significant differences in item and dimension scores and in significantly poorer fit when factor loadings were constrained to equality across all samples. Exploratory analyses with a second adjective measure of spirituality using American, Indian, and Ugandan samples identified three replicable factors which correlated with ESI-R dimensions in a manner supportive of convergent validity. The paper concludes with a discussion of the meaning of the findings and directions needed for future research. PMID:25734921
Khanjari, Sedigheh; Oskouie, Fatemeh; Langius-Eklöf, Ann
2012-02-01
To translate and test the reliability and validity of the Persian version of the Caregiver Quality of Life Index-Cancer scale. Research across many countries has determined quality of life of cancer patients, but few attempts have been made to measure the quality of life of family caregivers of patients with breast cancer. The Caregiver Quality of Life Index-Cancer scale was developed for this purpose, but until now, it has not been translated into or tested in the Persian language. Methodological research design. After standard translation, the 35-item Caregiver Quality of Life Index-Cancer scale was administered to 166 Iranian family caregivers of patients with breast cancer. A confirmatory factor analysis was carried out using LISREL to test the scale's construct validity. Further, the internal consistency and convergent validity of the instrument were tested. For convergent validity, four instruments were used in the study: sense of coherence scale, spirituality perspective scale, health index and brief religious coping scale. The confirmatory factor analysis resulted in the same four-factor structure as the original, though, with somewhat different item loadings. The Persian version of the Caregiver Quality of Life Index-Cancer scales had satisfactory internal consistency (0·72-0·90). Tests of convergent validity showed that all hypotheses were confirmed. A hierarchical multiple regression analysis additionally confirmed the convergent validity between the total Caregiver Quality of Life Index-Cancer score and sense of coherence (β = 0·34), negative religious coping (β = -0·21), education (β = 0·24) and the more severe stage of breast cancer (β = 0·23), in total explaining 41% of the variance. The Persian version of the Caregiver Quality of Life Index-Cancer scale could be a reliable and valid measure in Iranian family caregivers of patients with breast cancer. The Persian version of the Caregiver Quality of Life Index-Cancer scale is simple to administer and will help nurses to identify the nursing needs of family caregivers. © 2011 Blackwell Publishing Ltd.
Neale, Chris; Madill, Chris; Rauscher, Sarah; Pomès, Régis
2013-08-13
All molecular dynamics simulations are susceptible to sampling errors, which degrade the accuracy and precision of observed values. The statistical convergence of simulations containing atomistic lipid bilayers is limited by the slow relaxation of the lipid phase, which can exceed hundreds of nanoseconds. These long conformational autocorrelation times are exacerbated in the presence of charged solutes, which can induce significant distortions of the bilayer structure. Such long relaxation times represent hidden barriers that induce systematic sampling errors in simulations of solute insertion. To identify optimal methods for enhancing sampling efficiency, we quantitatively evaluate convergence rates using generalized ensemble sampling algorithms in calculations of the potential of mean force for the insertion of the ionic side chain analog of arginine in a lipid bilayer. Umbrella sampling (US) is used to restrain solute insertion depth along the bilayer normal, the order parameter commonly used in simulations of molecular solutes in lipid bilayers. When US simulations are modified to conduct random walks along the bilayer normal using a Hamiltonian exchange algorithm, systematic sampling errors are eliminated more rapidly and the rate of statistical convergence of the standard free energy of binding of the solute to the lipid bilayer is increased 3-fold. We compute the ratio of the replica flux transmitted across a defined region of the order parameter to the replica flux that entered that region in Hamiltonian exchange simulations. We show that this quantity, the transmission factor, identifies sampling barriers in degrees of freedom orthogonal to the order parameter. The transmission factor is used to estimate the depth-dependent conformational autocorrelation times of the simulation system, some of which exceed the simulation time, and thereby identify solute insertion depths that are prone to systematic sampling errors and estimate the lower bound of the amount of sampling that is required to resolve these sampling errors. Finally, we extend our simulations and verify that the conformational autocorrelation times estimated by the transmission factor accurately predict correlation times that exceed the simulation time scale-something that, to our knowledge, has never before been achieved.
Vortical structures and development of laminar flow over convergent-divergent riblets
NASA Astrophysics Data System (ADS)
Xu, Fang; Zhong, Shan; Zhang, Shanying
2018-05-01
In this work, the development of a laminar boundary layer over a rectangular convergent-divergent riblet section with a finite streamwise length is studied experimentally using dye visualization and particle image velocimetry in a water flume. The flow topology over this highly directional spanwise roughness is established from this study. It is shown that convergent-divergent riblets generate a spanwise flow above the riblets from the diverging line toward the adjacent converging line. This consequently leads to the formation of a weak recirculating secondary flow in cross-stream planes across the boundary layer that creates a downwash motion over the diverging line and an upwash motion over the converging line. It is found that the fluid inside the riblet valley follows a helicoidal path and it also interacts with the crossflow boundary layer hence playing a key role in determining the structure of the secondary flow across the boundary layer. The impact of riblet wavelength on vortical structures is also revealed for the first time. A larger riblet wavelength is seen to produce a stronger upwash/downwash and hence a more intense secondary flow as well as a stronger deceleration effect on the crossflow. Furthermore, the streamwise development of the flow over the riblet section can be divided into a developing stage followed by a developed stage. In the developing stage, the magnitude of induced streamwise velocity and vorticity over the converging line continues to increase, whereas in the developed stage the values of these parameters remain essentially unchanged.
Self-adaptive predictor-corrector algorithm for static nonlinear structural analysis
NASA Technical Reports Server (NTRS)
Padovan, J.
1981-01-01
A multiphase selfadaptive predictor corrector type algorithm was developed. This algorithm enables the solution of highly nonlinear structural responses including kinematic, kinetic and material effects as well as pro/post buckling behavior. The strategy involves three main phases: (1) the use of a warpable hyperelliptic constraint surface which serves to upperbound dependent iterate excursions during successive incremental Newton Ramphson (INR) type iterations; (20 uses an energy constraint to scale the generation of successive iterates so as to maintain the appropriate form of local convergence behavior; (3) the use of quality of convergence checks which enable various self adaptive modifications of the algorithmic structure when necessary. The restructuring is achieved by tightening various conditioning parameters as well as switch to different algorithmic levels to improve the convergence process. The capabilities of the procedure to handle various types of static nonlinear structural behavior are illustrated.
Mokhtarinia, Hamid Reza; Hosseini, Azadeh; Maleki-Ghahfarokhi, Azam; Gabel, Charles Philip; Zohrabi, Majid
2018-05-15
There are various instruments and methods to evaluate spinal health and functional status. Whole-spine patient reported outcome (PRO) measures, such as the Spine Functional Index (SFI), assess the spine from the cervical to lumbo-sacral sections as a single kinetic chain. The aim of this study was to cross-culturally adapt the SFI for Persian speaking patients (SFI-Pr) and determine the psychometric properties of reliability and validity (convergent and construct) in a Persian patient population. The SFI (English) PRO was translated into Persian according to published guidelines. Consecutive symptomatic spine patients (104 female and 120 male aged between 18 and 60) were recruited from three Iranian physiotherapy centers. Test-retest reliability was performed in a sub-sample (n = 31) at baseline and repeated between days 3-7. Convergent validity was determined by calculating the Pearson's r correlation coefficient between the SFI-Pr and the Persian Roland Morris Questionnaire (RMQ) for back pain patients and the Neck Disability Index (NDI) for neck patients. Internal consistency was assessed using Cronbach's α. Exploratory Factor Analysis (EFA) used Maximum Likelihood Extraction followed by Confirmatory Factor Analysis (CFA). High levels of internal consistency (α = 0.81, item range = 0.78-0.82) and test-retest reliability (r = 0.96, item range = 0.83-0.98) were obtained. Convergent validity was very good between the SFI and RMQ (r = 0.69) and good between the SFI and NDI (r = 0.57). The EFA from the perspective of parsimony suggests a one-factor solution that explained 26.5% of total variance. The CFA was inconclusive of the one factor structure as the sample size was inadequate. There were no floor or ceiling effects. The SFI-Pr PRO can be applied as a specific whole-spine status assessment instrument for clinical and research studies in Persian language populations.
Laborde, Sylvain; Dosseville, Fabrice; Aloui, Asma; Ben Saad, Helmi; Bertollo, Maurizio; Bortoli, Laura; Braun, Barbara; Chamari, Karim; Chtourou, Hamdi; De Kort, Yvonne; Farooq, Abdulaziz; Gordijn, Marijke Cm; Greco, Pablo; Guillén, Félix; Haddad, Monoem; Hosang, Thomas; Khalladi, Karim; Lericollais, Romain; Lopes, Mariana; Robazza, Claudio; Smolders, Karin; Wurm, Alexander; Allen, Mark S
2018-06-06
Chronotype questionnaires provide a simple and time-effective approach to assessing individual differences in circadian variations. Chronotype questionnaires traditionally focused on one dimension of chronotype, namely its orientation along a continuum of morningness and eveningness. The Caen Chronotype Questionnaire (CCQ) was developed to assess an additional dimension of chronotype that captures the extent to which individual functioning varies during the day (amplitude). The aim of this study was to provide a multilanguage validation of the CCQ in six world regions (Arabic, Dutch, German, Italian, Portuguese and Spanish). At Time 1, a total of 2788 participants agreed to take part in the study (Arabic, n = 731; Dutch, n = 538; German, n = 329; Italian, n = 473; Portuguese, n = 361; Spanish, n = 356). Participants completed an assessment of the CCQ together with the Morningness-Eveningness Questionnaire (MEQ; Horne & Ostberg 1976) as well as questions related to factors theoretically related to chronotype (age, shift work, physical activity, sleep parameters and coffee consumption). One month later, participants again completed the CCQ. Results showed that the two-factor structure (morningness-eveningness and amplitude) of the CCQ could be replicated in all six languages. However, measurement invariance could not be assumed regarding the factor loadings across languages, meaning that items loaded more on their factors in some translations than in others. Test-retest reliability of the CCQ ranged from unacceptable (German version) to excellent (Dutch, Portuguese). Convergent validity was established through small-medium effect size correlations between the morningness-eveningness dimension of the CCQ and the MEQ. Taken together, our findings generally support the use of the translated versions of the CCQ. Further validation work on the CCQ is required including convergent validation against physiological markers of sleep, health and well-being.
Poteat, V Paul; DiGiovanni, Craig D; Scheer, Jillian R
2013-03-01
As a form of bias-based harassment, homophobic behavior remains prominent in schools. Yet, little attention has been given to factors that underlie it, aside from bullying and sexual prejudice. Thus, we examined multiple domain general (empathy, perspective-taking, classroom respect norms) and sexual orientation-specific factors (sexual orientation identity importance, number of sexual minority friends, parents' sexual minority attitudes, media messages). We documented support for a model in which these sets of factors converged to predict homophobic behavior, mediated through bullying and prejudice, among 581 students in grades 9-12 (55 % female). The structural equation model indicated that, with the exception of media messages, these additional factors predicted levels of prejudice and bullying, which in turn predicted the likelihood of students to engage in homophobic behavior. These findings highlight the importance of addressing multiple interrelated factors in efforts to reduce bullying, prejudice, and discrimination among youth.
NASA Astrophysics Data System (ADS)
Panosetti, Davide; Schlemmer, Linda; Schär, Christoph
2018-05-01
Convection-resolving models (CRMs) can explicitly simulate deep convection and resolve interactions between convective updrafts. They are thus increasingly used in numerous weather and climate applications. However, the truncation of the continuous energy cascade at scales of O (1 km) poses a serious challenge, as in kilometer-scale simulations the size and properties of the simulated convective cells are often determined by the horizontal grid spacing (Δ x ).In this study, idealized simulations of deep moist convection over land are performed to assess the convergence behavior of a CRM at Δ x = 8, 4, 2, 1 km and 500 m. Two types of convergence estimates are investigated: bulk convergence addressing domain-averaged and integrated variables related to the water and energy budgets, and structural convergence addressing the statistics and scales of individual clouds and updrafts. Results show that bulk convergence generally begins at Δ x =4 km, while structural convergence is not yet fully achieved at the kilometer scale, despite some evidence that the resolution sensitivity of updraft velocities and convective mass fluxes decreases at finer resolution. In particular, at finer grid spacings the maximum updraft velocity generally increases, and the size of the smallest clouds is mostly determined by Δ x . A number of different experiments are conducted, and it is found that the presence of orography and environmental vertical wind shear yields more energetic structures at scales much larger than Δ x , sometimes reducing the resolution sensitivity. Overall the results lend support to the use of kilometer-scale resolutions in CRMs, despite the inability of these models to fully resolve the associated cloud field.
Extension and gold mineralisation in the hanging walls of active convergent continental shear zones
NASA Astrophysics Data System (ADS)
Upton, Phaedra; Craw, Dave
2014-07-01
Orogenic gold-bearing quartz veins form in mountain belts adjacent to convergent tectonic boundaries. The vein systems, hosted in extensional structures within compressively deformed rocks, are a widespread feature of these orogens. In many cases the extensional structures that host gold-bearing veins have been superimposed on, and locally controlled by, compressional structures formed within the convergent orogen. Exploring these observations within the context of a three-dimensional mechanical model allows prediction of mechanisms and locations of extensional zones within convergent orogens. Our models explore the effect of convergence angle and mid-crustal strength on stress states and compare them to the Southern Alps and Taiwan. The dilatation zones coincide with the highest mountains, in the hanging walls of major plate boundary faults, and can extend as deep as the brittle-ductile transition. Extensional deformation is favoured in the topographic divide region of oblique orogens with mid-lower crustal rheology that promotes localisation rather than diffuse deformation. In the near surface, topography influences the stress state to a depth approximately equal to the topographic relief, bringing the rock closer to failure and rotating σ1 to near vertical. The distribution of gold-bearing extensional veins may indicate the general position of the topographic divide within exhumed ancient orogens.
Numerical Computation of Subsonic Conical Diffuser Flows with Nonuniform Turbulent Inlet Conditions
1977-09-01
Gauss - Seidel Point Iteration Method . . . . . . . . . . . . . . . 7.0 FACTORS AFFECTING THE RATE OF CONVERGENCE OF THE POINT...can be solved in several ways. For simplicity, a standard Gauss - Seidel iteration method is used to obtain the solution . The method updates the...FACTORS AFFECTING THE RATE OF CONVERGENCE OF THE POINT ITERATION ,ŘETHOD The advantage of using the Gauss - Seidel point iteration method to
The analytic structure of non-global logarithms: Convergence of the dressed gluon expansion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Larkoski, Andrew J.; Moult, Ian; Neill, Duff Austin
Non-global logarithms (NGLs) are the leading manifestation of correlations between distinct phase space regions in QCD and gauge theories and have proven a challenge to understand using traditional resummation techniques. Recently, the dressed gluon ex-pansion was introduced that enables an expansion of the NGL series in terms of a “dressed gluon” building block, defined by an all-orders factorization theorem. Here, we clarify the nature of the dressed gluon expansion, and prove that it has an infinite radius of convergence as a solution to the leading logarithmic and large-N c master equation for NGLs, the Banfi-Marchesini-Smye (BMS) equation. The dressed gluonmore » expansion therefore provides an expansion of the NGL series that can be truncated at any order, with reliable uncertainty estimates. In contrast, manifest in the results of the fixed-order expansion of the BMS equation up to 12-loops is a breakdown of convergence at a finite value of α slog. We explain this finite radius of convergence using the dressed gluon expansion, showing how the dynamics of the buffer region, a region of phase space near the boundary of the jet that was identified in early studies of NGLs, leads to large contributions to the fixed order expansion. We also use the dressed gluon expansion to discuss the convergence of the next-to-leading NGL series, and the role of collinear logarithms that appear at this order. Finally, we show how an understanding of the analytic behavior obtained from the dressed gluon expansion allows us to improve the fixed order NGL series using conformal transformations to extend the domain of analyticity. Furthermore, this allows us to calculate the NGL distribution for all values of α slog from the coefficients of the fixed order expansion.« less
The analytic structure of non-global logarithms: Convergence of the dressed gluon expansion
Larkoski, Andrew J.; Moult, Ian; Neill, Duff Austin
2016-11-15
Non-global logarithms (NGLs) are the leading manifestation of correlations between distinct phase space regions in QCD and gauge theories and have proven a challenge to understand using traditional resummation techniques. Recently, the dressed gluon ex-pansion was introduced that enables an expansion of the NGL series in terms of a “dressed gluon” building block, defined by an all-orders factorization theorem. Here, we clarify the nature of the dressed gluon expansion, and prove that it has an infinite radius of convergence as a solution to the leading logarithmic and large-N c master equation for NGLs, the Banfi-Marchesini-Smye (BMS) equation. The dressed gluonmore » expansion therefore provides an expansion of the NGL series that can be truncated at any order, with reliable uncertainty estimates. In contrast, manifest in the results of the fixed-order expansion of the BMS equation up to 12-loops is a breakdown of convergence at a finite value of α slog. We explain this finite radius of convergence using the dressed gluon expansion, showing how the dynamics of the buffer region, a region of phase space near the boundary of the jet that was identified in early studies of NGLs, leads to large contributions to the fixed order expansion. We also use the dressed gluon expansion to discuss the convergence of the next-to-leading NGL series, and the role of collinear logarithms that appear at this order. Finally, we show how an understanding of the analytic behavior obtained from the dressed gluon expansion allows us to improve the fixed order NGL series using conformal transformations to extend the domain of analyticity. Furthermore, this allows us to calculate the NGL distribution for all values of α slog from the coefficients of the fixed order expansion.« less
To accrete or not accrete, that is the question
von Huene, Roland E.
1986-01-01
Along modern convergent margins tectonic processes span a spectrum from accretion to erosion. The process of accretion is generally recognized because it leaves a geologic record, whereas the process of erosion is generally hypothetical because it produces a geologic hiatus. Major conditions that determine the dominance of accretion or erosion at modern convergent margins are: 1) rate and direction of plate convergence, 2) sediment supply and type in the trench, and 3) topography of the subducting ocean floor. Most change in structure has been ascribed to plate motion, but both erosion and accretion are observed along the same convergence margin. Thus sediment supply and topography are probably of equivalent importance to plate motion because both erosion and accretion are observed under constant conditions of plate convergence. The dominance of accretion or erosion at a margin varies with the thickness of trench sediment. In a sediment flooded trench, the proportions of subducted and accreted sediment are commonly established by the position of a decollement along a weak horizon in the sediment section. Thus, the vertical variation of sediment strength and the distribution of horizontal stress are important factors. Once deformation begins, the original sediment strength is decreased by sediment remolding and where sediment thickens rapidly, increases in pore fluid pressure can be pronounced. In sediment-starved trenches, where the relief of the subducting ocean floor is not smoothed over, the front of the margin must respond to the topography subducted as well as that accreted. The hypothesized erosion by the drag of positive features against the underside of the upper plate (a high stress environment) may alternate with erosion due to the collapse of a margin front into voids such as graben (a low stress environment). ?? 1986 Ferdinand Enke Verlag Stuttgart.
Psychometric Properties of the “Sport Motivation Scale (SMS)” Adapted to Physical Education
Granero-Gallegos, Antonio; Baena-Extremera, Antonio; Gómez-López, Manuel; Sánchez-Fuentes, José Antonio; Abraldes, J. Arturo
2014-01-01
The aim of this study was to investigate the factor structure of a Spanish version of the Sport Motivation Scale adapted to physical education. A second aim was to test which one of three hypothesized models (three, five and seven-factor) provided best model fit. 758 Spanish high school students completed the Sport Motivation Scale adapted for Physical Education and also completed the Learning and Performance Orientation in Physical Education Classes Questionnaire. We examined the factor structure of each model using confirmatory factor analysis and also assessed internal consistency and convergent validity. The results showed that all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model (χ2/gl = 2.73; ECVI = 1.38) as it produces better values when adapted to physical education, that five-factor model (χ2/gl = 2.82; ECVI = 1.44) and three-factor model (χ2/gl = 3.02; ECVI = 1.53). Key Points Physical education research conducted in Spain has used the version of SMS designed to assess motivation in sport, but validity reliability and validity results in physical education have not been reported. Results of the present study lend support to the factorial validity and internal reliability of three alternative factor structures (3, 5, and 7 factors) of SMS adapted to Physical Education in Spanish. Although all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model. PMID:25435772
Senín-Calderón, Cristina; Valdés-Díaz, María; Benítez-Hernández, Ma M.; Núñez-Gaitán, Ma C.; Perona-Garcelán, Salvador; Martínez-Cervantes, Rafael; Rodríguez-Testal, Juan F.
2017-01-01
Dysmorphic concern (DC) refers to excessive preoccupation with a slight or imagined defect in physical appearance with social avoidance and behavior directed at controlling the defect in appearance. This study attempted to adapt the factor structure of two instruments that cover the DC construct, the Dysmorphic Concern Questionnaire (DCQ) and the Body Dysmorphic Disorder Examination Self-Report (BDDE-SR), to Spanish and establish their psychometric properties. A total of 920 subjects (62.7% women, Mage = 32.44 years) participated. Exploratory and Confirmatory Factor Analysis of both scales found adequate goodness of fit indices. A one-dimensional structure was found for the DCQ and two first-order factors (dissatisfaction/preoccupation with body image (BI) and BI avoidance behavior) were identified for the BDDE-SR. The psychometric test–retest reliability and validity properties (content, convergent, and discriminant) were satisfactory. It is suggested that the DC construct includes both cognitive and behavioral aspects and may represent a continuum of severity with Body Dysmorphic Disorder at the end. PMID:28713311
Senín-Calderón, Cristina; Valdés-Díaz, María; Benítez-Hernández, Ma M; Núñez-Gaitán, Ma C; Perona-Garcelán, Salvador; Martínez-Cervantes, Rafael; Rodríguez-Testal, Juan F
2017-01-01
Dysmorphic concern (DC) refers to excessive preoccupation with a slight or imagined defect in physical appearance with social avoidance and behavior directed at controlling the defect in appearance. This study attempted to adapt the factor structure of two instruments that cover the DC construct, the Dysmorphic Concern Questionnaire (DCQ) and the Body Dysmorphic Disorder Examination Self-Report (BDDE-SR), to Spanish and establish their psychometric properties. A total of 920 subjects (62.7% women, M age = 32.44 years) participated. Exploratory and Confirmatory Factor Analysis of both scales found adequate goodness of fit indices. A one-dimensional structure was found for the DCQ and two first-order factors (dissatisfaction/preoccupation with body image (BI) and BI avoidance behavior) were identified for the BDDE-SR. The psychometric test-retest reliability and validity properties (content, convergent, and discriminant) were satisfactory. It is suggested that the DC construct includes both cognitive and behavioral aspects and may represent a continuum of severity with Body Dysmorphic Disorder at the end.
Why stop self-injuring? Development of the reasons to stop self-injury questionnaire.
Turner, Brianna J; Chapman, Alexander L; Gratz, Kim L
2014-01-01
We developed a measure of reasons to refrain from nonsuicidal self-injury (NSSI), the Reasons to Stop Self-Injury Questionnaire (RSSIQ), and examined how such reasons are associated with vulnerability versus resiliency for NSSI. Following qualitative item generation, we explored the factor structure, reliability, and convergent validity of the RSSIQ in 218 self-injuring undergraduates. In Study 2, we confirmed the hierarchical factor structure in 146 self-injuring individuals. In Study 3, we examined the incremental predictive validity of the RSSIQ. These studies resulted in a 40-item inventory with nine subscales and two higher-order factors. Resiliency-related reasons to stop NSSI were associated with greater hopefulness, social support, and adaptive coping, and prospectively protected against NSSI 3 months later, while vulnerability-related reasons were associated with greater psychopathology and dysfunctional coping, and predicted more chronic and severe NSSI. These studies, and the RSSIQ, can enhance the assessment and treatment of NSSI by clarifying motivations to stop NSSI.
Littleton, Heather; Breitkopf, Carmen Radecki
2008-12-01
Dysmorphic appearance concern encompasses preoccupation with a perceived appearance defect, defect checking and camouflaging, and social avoidance. The current study sought to evaluate the internal consistency, factor structure, and convergent validity of a measure of dysmorphic appearance concern, the Body Image Concern Inventory, as well as evaluate the psychometric properties of a Spanish version of the instrument. Women recruited as part of a reproductive clinic-based clinical trial completed the BICI and other self-report measures of distress. A total of 1043 women completed the measures in English (M=29 years, range=18-55 years) and 573 women completed the measures in Spanish (M=32 years, range=18-55 years). Both the English and Spanish BICI were internally consistent and correlated moderately with measures of current psychological distress (STAI-S, CES-D). Confirmatory factor analyses replicated the measure's proposed factor structure. Applications of the BICI for future research are discussed.
Wright, Aidan G. C.; Hallquist, Michael N.; Stepp, Stephanie D.; Scott, Lori N.; Beeney, Joseph E.; Lazarus, Sophie A.; Pilkonis, Paul A.
2016-01-01
Borderline personality disorder (BPD) is a diagnosis defined by impairments in several dynamic processes (e.g., interpersonal relating, affect regulation, behavioral control). Theories of BPD emphasize that these impairments appear in specific contexts, and emerging results confirm this view. At the same time, BPD is a complex construct that encompasses individuals with heterogeneous pathology. These features—dynamic processes, situational specificity, and individual heterogeneity—pose significant assessment challenges. In the current study, we demonstrate assessment and analytic methods that capture both between-person differences and within-person changes over time. Twenty-five participants diagnosed with BPD completed event-contingent, ambulatory assessment protocols over 21 days. We used p-technique factor analyses to identify person-specific psychological structures consistent with clinical theories of personality. Five exemplar cases are selected and presented in detail to showcase the potential utility of these methods. The presented cases' factor structures reflect not only heterogeneity but also suggest points of convergence. The factors also demonstrated significant associations with important clinical targets (self-harm, interpersonal violence). PMID:27317561
Mindful attention and awareness: relationships with psychopathology and emotion regulation.
Gregório, Sónia; Pinto-Gouveia, José
2013-01-01
The growing interest in mindfulness from the scientific community has originated several self-report measures of this psychological construct. The Mindful Attention and Awareness Scale (MAAS) is a self-report measure of mindfulness at a trait-level. This paper aims at exploring MAAS psychometric characteristics and validating it for the Portuguese population. The first two studies replicate some of the original author's statistical procedures in two different samples from the Portuguese general community population, in particular confirmatory factor analyses. Results from both analyses confirmed the scale single-factor structure and indicated a very good reliability. Moreover, cross-validation statistics showed that this single-factor structure is valid for different respondents from the general community population. In the third study the Portuguese version of the MAAS was found to have good convergent and discriminant validities. Overall the findings support the psychometric validity of the Portuguese version of MAAS and suggest this is a reliable self-report measure of trait-mindfulness, a central construct in Clinical Psychology research and intervention fields.
Fok, Carlotta Ching Ting; Allen, James; Henry, David
2014-02-01
The Relationship dimension of the Family Environment Scale, which consists of the Cohesion, Expressiveness, and Conflict subscales, measures a person's perception of the quality of his or her family relationship functioning. This study investigates an adaptation of the Relationship dimension of the Family Environment Scale for Alaska Native youth. The authors tested the adapted measure, the Brief Family Relationship Scale, for psychometric properties and internal structure with 284 12- to 18-year-old predominately Yup'ik Eskimo Alaska Native adolescents from rural, remote communities. This non-Western cultural group is hypothesized to display higher levels of collectivism traditionally organized around an extended kinship family structure. Results demonstrate a subset of the adapted items function satisfactorily, a three-response alternative format provided meaningful information, and the subscale's underlying structure is best described through three distinct first-order factors, organized under one higher order factor. Convergent and discriminant validity of the Brief Family Relationship Scale was assessed through correlational analysis.
Forbes, Miriam K; Kotov, Roman; Ruggero, Camilo J; Watson, David; Zimmerman, Mark; Krueger, Robert F
2017-11-01
A large body of research has focused on identifying the optimal number of dimensions - or spectra - to model individual differences in psychopathology. Recently, it has become increasingly clear that ostensibly competing models with varying numbers of spectra can be synthesized in empirically derived hierarchical structures. We examined the convergence between top-down (bass-ackwards or sequential principal components analysis) and bottom-up (hierarchical agglomerative cluster analysis) statistical methods for elucidating hierarchies to explicate the joint hierarchical structure of clinical and personality disorders. Analyses examined 24 clinical and personality disorders based on semi-structured clinical interviews in an outpatient psychiatric sample (n=2900). The two methods of hierarchical analysis converged on a three-tier joint hierarchy of psychopathology. At the lowest tier, there were seven spectra - disinhibition, antagonism, core thought disorder, detachment, core internalizing, somatoform, and compulsivity - that emerged in both methods. These spectra were nested under the same three higher-order superspectra in both methods: externalizing, broad thought dysfunction, and broad internalizing. In turn, these three superspectra were nested under a single general psychopathology spectrum, which represented the top tier of the hierarchical structure. The hierarchical structure mirrors and extends upon past research, with the inclusion of a novel compulsivity spectrum, and the finding that psychopathology is organized in three superordinate domains. This hierarchy can thus be used as a flexible and integrative framework to facilitate psychopathology research with varying levels of specificity (i.e., focusing on the optimal level of detailed information, rather than the optimal number of factors). Copyright © 2017 Elsevier Inc. All rights reserved.
Probing dark energy using convergence power spectrum and bi-spectrum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dinda, Bikash R., E-mail: bikash@ctp-jamia.res.in
Weak lensing convergence statistics is a powerful tool to probe dark energy. Dark energy plays an important role to the structure formation and the effects can be detected through the convergence power spectrum, bi-spectrum etc. One of the most promising and simplest dark energy model is the ΛCDM . However, it is worth investigating different dark energy models with evolving equation of state of the dark energy. In this work, detectability of different dark energy models from ΛCDM model has been explored through convergence power spectrum and bi-spectrum.
Reply to "Comment on `Route from discreteness to the continuum for the Tsallis q -entropy' "
NASA Astrophysics Data System (ADS)
Oikonomou, Thomas; Bagci, G. Baris
2018-06-01
It has been known for some time that the usual q -entropy Sq(n ) cannot be shown to converge to the continuous case. In Phys. Rev. E 97, 012104 (2018), 10.1103/PhysRevE.97.012104, we have shown that the discrete q -entropy S˜q(n ) converges to the continuous case when the total number of states are properly taken into account in terms of a convergence factor. Ou and Abe [previous Comment, Phys. Rev. E 97, 066101 (2018), 10.1103/PhysRevE.97.066101] noted that this form of the discrete q -entropy does not conform to the Shannon-Khinchin expandability axiom. As a reply, we note that the fulfillment or not of the expandability property by the discrete q -entropy strongly depends on the origin of the convergence factor, presenting an example in which S˜q(n ) is expandable.
Weighted Global Artificial Bee Colony Algorithm Makes Gas Sensor Deployment Efficient
Jiang, Ye; He, Ziqing; Li, Yanhai; Xu, Zhengyi; Wei, Jianming
2016-01-01
This paper proposes an improved artificial bee colony algorithm named Weighted Global ABC (WGABC) algorithm, which is designed to improve the convergence speed in the search stage of solution search equation. The new method not only considers the effect of global factors on the convergence speed in the search phase, but also provides the expression of global factor weights. Experiment on benchmark functions proved that the algorithm can improve the convergence speed greatly. We arrive at the gas diffusion concentration based on the theory of CFD and then simulate the gas diffusion model with the influence of buildings based on the algorithm. Simulation verified the effectiveness of the WGABC algorithm in improving the convergence speed in optimal deployment scheme of gas sensors. Finally, it is verified that the optimal deployment method based on WGABC algorithm can improve the monitoring efficiency of sensors greatly as compared with the conventional deployment methods. PMID:27322262
Antunes, Ana Cristina; Caetano, António; Pina E Cunha, Miguel
2017-06-01
The Psychological Capital Questionnaire (PCQ) is the most commonly used measure for assessing psychological capital in work settings. Although several studies confirmed its factorial validity, most validation studies only examined the four-factor structure preconized by Luthans, Youssef, and Avolio, not attending to empirical evidence on alternative factorial structures. The present study aimed to test the psychometric properties of the Portuguese version of the PCQ, by using two independent samples (NS1 = 542; NS2 = 115) of Portuguese employees. We conducted a series of confirmatory factor analyses and found that, unlike previous findings, a five-factor solution of the PCQ best fitted the data. The evidence obtained also supported the existence of a second-order factor, psychological capital. The coefficients of internal consistency, as measured by Cronbach's alpha, were adequate and test-retest reliability suggested that the PCQ presented a lower stability than personality factors. Convergent validity, assessed with average variance extracted, revealed problems in the optimism subscale. The discriminant validity of the PCQ was confirmed by its correlations with Positive and Negative Affect and Big Five personality factors. Hierarchical regression analyses showed that this measure has incremental validity over personality and affect when predicting job performance.
Yanos, Philip T; Vayshenker, Beth; DeLuca, Joseph S; O'Connor, Lauren K
2017-10-01
Mental health professionals who work with people with serious mental illnesses are believed to experience associative stigma. Evidence suggests that associative stigma could play an important role in the erosion of empathy among professionals; however, no validated measure of the construct currently exists. This study examined the convergent and discriminant validity and factor structure of a new scale assessing the associative stigma experiences of clinicians working with people with serious mental illnesses. A total of 473 clinicians were recruited from professional associations in the United States and participated in an online study. Participants completed the Clinician Associative Stigma Scale (CASS) and measures of burnout, quality of care, expectations about recovery, and self-efficacy. Associative stigma experiences were commonly endorsed; eight items on the 18-item scale were endorsed as being experienced "sometimes" or "often" by over 50% of the sample. The new measure demonstrated a logical four-factor structure: "negative stereotypes about professional effectiveness," "discomfort with disclosure," "negative stereotypes about people with mental illness," and "stereotypes about professionals' mental health." The measure had good internal consistency. It was significantly related to measures of burnout and quality of care, but it was not related to measures of self-efficacy or expectations about recovery. Findings suggest that the CASS is internally consistent and shows evidence of convergent validity and that associative stigma is commonly experienced by mental health professionals who work with people with serious mental illnesses.
Kolokotroni, Philippa; Anagnostopoulos, Fotios; Missitzis, Ioannis
2017-07-01
The study and measurement of psychosocial adjustment is important for evaluating patients' well-being, and assessing the illness's course, treatment's success, and patients' recovery. In this study, internal consistency reliability and construct validity of the Greek version of the Psychosocial Adjustment to Illness Scale-Self-Report (PAIS-SR) were examined. Demographic and psychosocial data were collected from a sample of 243 women with breast cancer, recruited from September 2011 to December 2012. With some exceptions in specific items, the original conceptually-derived PAIS-SR subscales emerged in a seven-factor solution. Social Environment, Job and Household Duties, and Psychological Distress accounted for more of the total variance than other subscales. PAIS-SR showed good internal consistency reliability, with Cronbach's alpha coefficients >0.62. Correlations of PAIS-SR domains with measures of quality of life and posttraumatic stress symptoms supported the convergent validity of the PAIS-SR and its significance for cancer research. The Greek version of the PAIS-SR has acceptable internal consistency reliability and construct validity, as well as satisfactory convergent validity. Results provide some suggestions for the development of programs to evaluate adjustment status and implement psychosocial interventions among breast cancer survivors.
Li, Yan; Hughes, Jan N.; Kwok, Oi-man; Hsu, Hsien-Yuan
2012-01-01
This study investigated the construct validity of measures of teacher-student support in a sample of 709 ethnically diverse second and third grade academically at-risk students. Confirmatory factor analysis investigated the convergent and discriminant validities of teacher, child, and peer reports of teacher-student support and child conduct problems. Results supported the convergent and discriminant validity of scores on the measures. Peer reports accounted for the largest proportion of trait variance and non-significant method variance. Child reports accounted for the smallest proportion of trait variance and the largest method variance. A model with two latent factors provided a better fit to the data than a model with one factor, providing further evidence of the discriminant validity of measures of teacher-student support. Implications for research, policy, and practice are discussed. PMID:21767024
Roth, David L.; Gitlin, Laura N.; Coon, David W.; Stevens, Alan B.; Burgio, Louis D.; Gallagher-Thompson, Dolores; Belle, Steven H.; Burns, Robert
2008-01-01
A modified version of the Revised Memory and Behavior Problems Checklist (RMBPC; L. Teri et al., 1992) was administered across 6 different sites to 1,229 family caregivers of community-dwelling adults with dementia. The total sample was divided randomly into 2 subsamples. Principal components analyses on occurrence responses and reaction ratings from the first subsample resulted in a 3-factor solution that closely resembled the originally proposed dimensions (memory-related problems, disruptive behaviors, and depression). Confirmatory factor analyses on data from the second subsample indicated adequate fit for the 3-factor model. Correlations with other caregiver and care-recipient measures supported the convergent and discriminant validity of the RMBPC measures. In addition, female caregivers and White caregivers reported more problems, on average, than male caregivers and African American caregivers, respectively. PMID:14692875
Berker, Yannick; Karp, Joel S; Schulz, Volkmar
2017-09-01
The use of scattered coincidences for attenuation correction of positron emission tomography (PET) data has recently been proposed. For practical applications, convergence speeds require further improvement, yet there exists a trade-off between convergence speed and the risk of non-convergence. In this respect, a maximum-likelihood gradient-ascent (MLGA) algorithm and a two-branch back-projection (2BP), which was previously proposed, were evaluated. MLGA was combined with the Armijo step size rule; and accelerated using conjugate gradients, Nesterov's momentum method, and data subsets of different sizes. In 2BP, we varied the subset size, an important determinant of convergence speed and computational burden. We used three sets of simulation data to evaluate the impact of a spatial scale factor. The Armijo step size allowed 10-fold increased step sizes compared to native MLGA. Conjugate gradients and Nesterov momentum lead to slightly faster, yet non-uniform convergence; improvements were mostly confined to later iterations, possibly due to the non-linearity of the problem. MLGA with data subsets achieved faster, uniform, and predictable convergence, with a speed-up factor equivalent to the number of subsets and no increase in computational burden. By contrast, 2BP computational burden increased linearly with the number of subsets due to repeated evaluation of the objective function, and convergence was limited to the case of many (and therefore small) subsets, which resulted in high computational burden. Possibilities of improving 2BP appear limited. While general-purpose acceleration methods appear insufficient for MLGA, results suggest that data subsets are a promising way of improving MLGA performance.
Kotzalidis, Georgios D; Solfanelli, Andrea; Piacentino, Daria; Savoja, Valeria; Fiori Nastro, Paolo; Curto, Martina; Lindau, Juliana Fortes; Masillo, Alice; Brandizzi, Martina; Fagioli, Francesca; Raballo, Andrea; Gebhardt, Eva; Preti, Antonio; D'Alema, Marco; Fucci, Maria Rosa; Miletto, Roberto; Andropoli, Daniela; Leccisi, Donato; Girardi, Paolo; Loewy, Rachel L; Schultze-Lutter, Frauke
2017-11-01
Current early screeners for psychosis-risk states have still to prove ability in identifying at-risk individuals. Among screeners, the 92-item Prodromal Questionnaire (PQ-92) is often used. We aimed to assess the validity of its Italian translation in a large Italian adolescent and young adult help-seeking sample. We included all individuals aged 12-36years seeking help at psychiatric mental health services in a large semirural Roman area (534,600 population) who accepted to participate. Participants completed the Italian version of the PQ-92 and were subsequently assessed with the Structured Interview of Prodromal/Psychosis-Risk Syndromes (SIPS). We examined diagnostic accuracy (sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios) and content, concurrent, and convergent validity between PQ-92 and SIPS using Cronbach's alpha, Cohen's kappa, and Spearman's rho, respectively. We tested the validity of adopted cut-offs through Receiver Operating Characteristic (ROC) curves plotted against SIPS diagnoses and the instrument's factor-structure through Principal Component Analysis. PQ-92 showed high internal consistency, acceptable diagnostic accuracy and concurrent validity, and excellent convergent validity. ROC analyses pointed to scores of 18 on the Positive subscale and 36 on the total PQ-92 as best cut-offs. The Scree-test identified a four-factor solution as fitting best. Psychometric properties of Italian PQ-92 were satisfactory. Optimal cut-offs were confirmed at ≥18 on the positive subscale, but at ≥36 on the total scale was able to identify more SIPS-positive cases. Copyright © 2017 Elsevier B.V. All rights reserved.
van Helmondt, Sanne Jasperine; van der Lee, Marije Liesbeth; de Vries, Jolanda
2017-11-01
The study objectives are to translate the FCRI in Dutch, and to explore the factor structure and the psychometric qualities of the Dutch translation of the Fear of Cancer Recurrence Inventory (FCRI-NL). The original French-Canadian FCRI had been forward-backward translated into English by the developers, and this method was also used to translate the English version of the FCRI into Dutch. Patients were recruited via patient organizations between July 2011 and October 2013. To replicate the original 7-factor structure of the FCRI, confirmatory factor analysis (CFA) was performed. To examine the psychometric qualities, reliability (Cronbach's alpha), test-retest reliability (intra-class correlations; ICC), and convergent and divergent validity (Spearman's correlations) were calculated. From 290 cancer patients, 255 (88%) were eligible for analysis (aged 51.0±9.8years, 88.6% women). CFA showed a reasonable yet suboptimal fit of the hypothesized model to the data. The FCRI-NL has good reliability (Cronbach's α=0.93 for the total scale and α=0.75-0.92 for the subscales) and test-retest reliability (ICC=0.84 for the total scale and ICC=0.56-0.87 for the subscales). Convergent (r=0.53-0.66 for the FCRI-NL and r=0.48-0.57 for the FCRI-SF-NL) and divergent (r=-0.20--0.07 for the FCRI-NL and r=-0.28--0.17 for the FCRI-SF-NL) validity was demonstrated. The FCRI-NL seems to have sufficient psychometric properties. However, the FCRI-NL total score should be interpreted with caution. The Severity subscale (FCRI-SF-NL) may be a valuable screening tool for fear of cancer recurrence severity in clinical care. Copyright © 2017. Published by Elsevier Inc.
Fitness to plead: Development and validation of a standardised assessment instrument
Stahl, Daniel; Appiah-Kusi, Elizabeth; Brewer, Rebecca; Watts, Michael; Peay, Jill; Blackwood, Nigel
2018-01-01
The ability of an individual to participate in courtroom proceedings is assessed by clinicians using legal ‘fitness to plead’ criteria. Findings of ‘unfitness’ are so rare that there is considerable professional unease concerning the utility of the current subjective assessment process. As a result, mentally disordered defendants may be subjected unfairly to criminal trials. The Law Commission in England and Wales has proposed legal reform, as well as the utilisation of a defined psychiatric instrument to assist in fitness to plead assessments. Similar legal reforms are occurring in other jurisdictions. Our objective was to produce and validate a standardised assessment instrument of fitness to plead employing a filmed vignette of criminal proceedings. The instrument was developed in consultation with legal and clinical professionals, and was refined using standard item reduction methods in two initial rounds of testing (n = 212). The factorial structure, test-retest reliability and convergent validity of the resultant instrument were assessed in a further round (n = 160). As a result of this iterative process a 25-item scale was produced, with an underlying two-factor structure representing the foundational and decision-making abilities underpinning fitness to plead. The sub-scales demonstrate good internal consistency (factor 1: 0·76; factor 2: 0·65) and test-retest stability (0·7) as well as excellent convergent validity with scores of intelligence, executive function and mentalising abilities (p≤0·01 in all domains). Overall the standardised Fitness to Plead Assessment instrument has good psychometric properties. It has the potential to ensure that the significant numbers of mentally ill and cognitively impaired individuals who face trial are objectively assessed, and the courtroom process critically informed. PMID:29698396
Exploring the Factor Structure of a Recovery Assessment Measure among Substance-Abusing Youth.
Gonzales, Rachel; Hernandez, Mayra; Douglas, Samantha B; Yu, Chong Ho
2015-01-01
To date, the measurement of recovery in the field of substance abuse is limited. Youth recovery from substance abuse is an important area to consider, given the complexities of such issues. The Recovery Assessment Scale (RAS) has been validated with mental health patient populations; however, its measurement characteristics have not been examined for individuals in substance abuse treatment. The current study explored the factor structure of the RAS with a sample of 80 substance-abusing youth who participated in a pilot aftercare study (Mage 20.5, SD=3.5; 71.3% male). Reliability analysis showed an internal consistency of α=.90 for the entire RAS measure among the youth sample. Results of exploratory factor analysis identified the following four factors: personal determination, skills for recovery, self-control in recovery, and social support/moving beyond recovery among the substance-abusing youth sample. The RAS also demonstrated sound convergent and divergent validity in comparison to other validated measures of functioning, sobriety, and well-being. Collectively, results support that the RAS has adequate psychometric properties for measuring recovery among substance-abusing youth.
da Silva, Wanderson Roberto; Dias, Juliana Chioda Ribeiro; Maroco, João; Campos, Juliana Alvares Duarte Bonini
2014-09-01
This study aimed at evaluating the validity, reliability, and factorial invariance of the complete (34-item) and shortened (8-item and 16-item) versions of the Body Shape Questionnaire (BSQ) when applied to Brazilian university students. A total of 739 female students with a mean age of 20.44 (standard deviation=2.45) years participated. Confirmatory factor analysis was conducted to verify the degree to which the one-factor structure satisfies the proposal for the BSQ's expected structure. Two items of the 34-item version were excluded because they had factor weights (λ)<40. All models had adequate convergent validity (average variance extracted=.43-.58; composite reliability=.85-.97) and internal consistency (α=.85-.97). The 8-item B version was considered the best shortened BSQ version (Akaike information criterion=84.07, Bayes information criterion=157.75, Browne-Cudeck criterion=84.46), with strong invariance for independent samples (Δχ(2)λ(7)=5.06, Δχ(2)Cov(8)=5.11, Δχ(2)Res(16)=19.30). Copyright © 2014 Elsevier Ltd. All rights reserved.
Dicke, Theresa; Marsh, Herbert W.; Riley, Philip; Parker, Philip D.; Guo, Jiesi; Horwood, Marcus
2018-01-01
School principals world-wide report high levels of strain and attrition resulting in a shortage of qualified principals. It is thus crucial to identify psychosocial risk factors that reflect principals' occupational wellbeing. For this purpose, we used the Copenhagen Psychosocial Questionnaire (COPSOQ-II), a widely used self-report measure covering multiple psychosocial factors identified by leading occupational stress theories. We evaluated the COPSOQ-II regarding factor structure and longitudinal, discriminant, and convergent validity using latent structural equation modeling in a large sample of Australian school principals (N = 2,049). Results reveal that confirmatory factor analysis produced marginally acceptable model fit. A novel approach we call set exploratory structural equation modeling (set-ESEM), where cross-loadings were only allowed within a priori defined sets of factors, fit well, and was more parsimonious than a full ESEM. Further multitrait-multimethod models based on the set-ESEM confirm the importance of a principal's psychosocial risk factors; Stressors and depression were related to demands and ill-being, while confidence and autonomy were related to wellbeing. We also show that working in the private sector was beneficial for showing a low psychosocial risk, while other demographics have little effects. Finally, we identify five latent risk profiles (high risk to no risk) of school principals based on all psychosocial factors. Overall the research presented here closes the theory application gap of a strong multi-dimensional measure of psychosocial risk-factors. PMID:29760670
Dicke, Theresa; Marsh, Herbert W; Riley, Philip; Parker, Philip D; Guo, Jiesi; Horwood, Marcus
2018-01-01
School principals world-wide report high levels of strain and attrition resulting in a shortage of qualified principals. It is thus crucial to identify psychosocial risk factors that reflect principals' occupational wellbeing. For this purpose, we used the Copenhagen Psychosocial Questionnaire (COPSOQ-II), a widely used self-report measure covering multiple psychosocial factors identified by leading occupational stress theories. We evaluated the COPSOQ-II regarding factor structure and longitudinal, discriminant, and convergent validity using latent structural equation modeling in a large sample of Australian school principals ( N = 2,049). Results reveal that confirmatory factor analysis produced marginally acceptable model fit. A novel approach we call set exploratory structural equation modeling (set-ESEM), where cross-loadings were only allowed within a priori defined sets of factors, fit well, and was more parsimonious than a full ESEM. Further multitrait-multimethod models based on the set-ESEM confirm the importance of a principal's psychosocial risk factors; Stressors and depression were related to demands and ill-being, while confidence and autonomy were related to wellbeing. We also show that working in the private sector was beneficial for showing a low psychosocial risk, while other demographics have little effects. Finally, we identify five latent risk profiles (high risk to no risk) of school principals based on all psychosocial factors. Overall the research presented here closes the theory application gap of a strong multi-dimensional measure of psychosocial risk-factors.
A class of convergent neural network dynamics
NASA Astrophysics Data System (ADS)
Fiedler, Bernold; Gedeon, Tomáš
1998-01-01
We consider a class of systems of differential equations in Rn which exhibits convergent dynamics. We find a Lyapunov function and show that every bounded trajectory converges to the set of equilibria. Our result generalizes the results of Cohen and Grossberg (1983) for convergent neural networks. It replaces the symmetry assumption on the matrix of weights by the assumption on the structure of the connections in the neural network. We prove the convergence result also for a large class of Lotka-Volterra systems. These are naturally defined on the closed positive orthant. We show that there are no heteroclinic cycles on the boundary of the positive orthant for the systems in this class.
Sachser, Cedric; Berliner, Lucy; Holt, Tonje; Jensen, Tine K; Jungbluth, Nathaniel; Risch, Elizabeth; Rosner, Rita; Goldbeck, Lutz
2017-03-01
Systematic screening is a powerful means by which children and adolescents with posttraumatic stress symptoms (PTSS) can be detected. Reliable and valid measures based on current diagnostic criteria are needed. To investigate the internal consistency and construct validity of the Child and Adolescent Trauma Screen (CATS) in three samples of trauma-exposed children in the US (self-reports: n=249; caregiver reports: n=267; pre-school n=190), in Germany (self-reports: n=117; caregiver reports: n=95) and in Norway (self-reports: n=109; caregiver reports: n=62). Internal consistency was calculated using Cronbach's α. Convergent-discriminant validity was investigated using bivariate correlation coefficients with measures of depression, anxiety and externalizing symptoms. CFA was used to investigate the DSM-5 factor structure. In all three language samples the 20 item symptom score of the self-report and the caregiver report proved good to excellent reliability with α ranging between .88 and .94. The convergent-discriminant validity pattern showed medium to strong correlations with measures of depression (r =.62-.82) and anxiety (r =.40-.77) and low to medium correlations with externalizing symptoms (r =-.15-.43) within informants in all language versions. Using CFA the underlying DSM-5 factor structure with four symptom clusters (re-experiencing, avoidance, negative alterations in mood and cognitions, hyperarousal) was supported (n =475 for self-report; n =424 for caregiver reports). The external validation of the CATS with a DSM-5 based semi-structured clinical interview and corresponding determination of cut-points is pending. The CATS has satisfactory psychometric properties. Clinicians may consider the CATS as a screening tool and for symptom monitoring. Copyright © 2016 Elsevier B.V. All rights reserved.
Ang, Rebecca P; Chong, Wan Har; Huan, Vivien S; Yeo, Lay See
2007-01-01
This article reports the development and initial validation of scores obtained from the Adolescent Concerns Measure (ACM), a scale which assesses concerns of Asian adolescent students. In Study 1, findings from exploratory factor analysis using 619 adolescents suggested a 24-item scale with four correlated factors--Family Concerns (9 items), Peer Concerns (5 items), Personal Concerns (6 items), and School Concerns (4 items). Initial estimates of convergent validity for ACM scores were also reported. The four-factor structure of ACM scores derived from Study 1 was confirmed via confirmatory factor analysis in Study 2 using a two-fold cross-validation procedure with a separate sample of 811 adolescents. Support was found for both the multidimensional and hierarchical models of adolescent concerns using the ACM. Internal consistency and test-retest reliability estimates were adequate for research purposes. ACM scores show promise as a reliable and potentially valid measure of Asian adolescents' concerns.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanus, Riley; Guo, Xingyu; Tang, Yinglu
2017-01-13
N-Type skutterudites, such as Yb xCo 4Sb 12, have recently been shown to exhibit high valley degeneracy with possible band convergence, explaining the excellent thermoelectric efficiency of these materials. Using a combined theoretical and experimental approach involving temperature-dependent synchrotron diffraction, molecular orbital diagrams, and computational studies, the chemical nature of critical features in the band structure is highlighted. We identify how n-type doping on the filler site induces structural changes that are observed in both the diffraction data and computational results. Additionally, we show how chemical n-type doping slightly alters the electronic band structure, moving the high-valley degeneracy secondary conductionmore » band closer to the primary conduction band and thus inducing band convergence.« less
Saksena, Sumeet; Fox, Jefferson; Epprecht, Michael; Tran, Chinh C.; Nong, Duong H.; Spencer, James H.; Nguyen, Lam; Finucane, Melissa L.; Tran, Vien D.; Wilcox, Bruce A.
2015-01-01
Building on a series of ground breaking reviews that first defined and drew attention to emerging infectious diseases (EID), the ‘convergence model’ was proposed to explain the multifactorial causality of disease emergence. The model broadly hypothesizes disease emergence is driven by the co-incidence of genetic, physical environmental, ecological, and social factors. We developed and tested a model of the emergence of highly pathogenic avian influenza (HPAI) H5N1 based on suspected convergence factors that are mainly associated with land-use change. Building on previous geospatial statistical studies that identified natural and human risk factors associated with urbanization, we added new factors to test whether causal mechanisms and pathogenic landscapes could be more specifically identified. Our findings suggest that urbanization spatially combines risk factors to produce particular types of peri-urban landscapes with significantly higher HPAI H5N1 emergence risk. The work highlights that peri-urban areas of Viet Nam have higher levels of chicken densities, duck and geese flock size diversities, and fraction of land under rice or aquaculture than rural and urban areas. We also found that land-use diversity, a surrogate measure for potential mixing of host populations and other factors that likely influence viral transmission, significantly improves the model’s predictability. Similarly, landscapes where intensive and extensive forms of poultry production overlap were found at greater risk. These results support the convergence hypothesis in general and demonstrate the potential to improve EID prevention and control by combing geospatial monitoring of these factors along with pathogen surveillance programs. PMID:26398118
Turner, Monica G; Whitby, Timothy G; Tinker, Daniel B; Romme, William H
2016-05-01
Disturbance and succession have long been of interest in ecology, but how landscape patterns of ecosystem structure and function evolve following large disturbances is poorly understood. After nearly 25 years, lodgepole pine (Pinus contorta var. latifolia) forests that regenerated after the 1988 Yellowstone Fires (Wyoming, USA) offer a prime opportunity to track the fate of disturbance-created heterogeneity in stand structure and function in a wilderness setting. In 2012, we resampled 72 permanent plots to ask (1) How have postfire stand structure and function changed between 11 and 24 yr postfire, and what variables explain these patterns and changes? (2) How has landscape-level (among-stand) variability in postfire stand structure and function changed between 11 and 24 yr postfire? We expected to see evidence of convergence beginning to emerge, but also that initial postfire stem density would still determine trajectories of biomass accumulation. After 24 yr, postfire lodgepole pine density remained very high (mean = 21,738 stems/ha, range = 0-344,067 stems/ha). Stem density increased in most plots between 11 and 24 yr postfire, but declined sharply where 11-yr-postfire stem density was > 72,000 stems/ha. Stems were small in high-density stands, but stand-level lodgepole pine leaf area, foliage biomass, and live aboveground biomass increased over time and with increasing stem density. After 24 yr, mean annual lodgepole pine aboveground net primary production (ANPP) was high (mean = 5 Mg · ha⁻¹ · yr⁻¹, range = 0-16.5 Mg · ha⁻¹ · yr⁻¹). Among stands, lodgepole pine ANPP increased with stem density, which explained 69% of the variation; another 8% of the variation was explained by environmental covariates. Early patterns of postfire lodgepole pine regeneration, which were contingent on prefire serotiny and fire severity, remained the dominant driver of stand structure and function. We observed mechanisms that would lead to convergence in stem density (structure) over time, but it was landscape variation in functional variables that declined substantially. Stand structure and function have not converged across the burned landscape, but our evidence suggests function will converge sooner than structure.
INCLEN Diagnostic Tool for Autism Spectrum Disorder (INDT-ASD): development and validation.
Juneja, Monica; Mishra, Devendra; Russell, Paul S S; Gulati, Sheffali; Deshmukh, Vaishali; Tudu, Poma; Sagar, Rajesh; Silberberg, Donald; Bhutani, Vinod K; Pinto, Jennifer M; Durkin, Maureen; Pandey, Ravindra M; Nair, M K C; Arora, Narendra K
2014-05-01
To develop and validate INCLEN Diagnostic Tool for Autism Spectrum Disorder (INDT-ASD). Diagnostic test evaluation by cross sectional design. Four tertiary pediatric neurology centers in Delhi and Thiruvanthapuram, India. Children aged 2-9 years were enrolled in the study. INDT-ASD and Childhood Autism Rating Scale (CARS) were administered in a randomly decided sequence by trained psychologist, followed by an expert evaluation by DSM-IV TR diagnostic criteria (gold standard). Psychometric parameters of diagnostic accuracy, validity (construct, criterion and convergent) and internal consistency. 154 children (110 boys, mean age 64.2 mo) were enrolled. The overall diagnostic accuracy (AUC=0.97, 95% CI 0.93, 0.99; P<0.001) and validity (sensitivity 98%, specificity 95%, positive predictive value 91%, negative predictive value 99%) of INDT-ASD for Autism spectrum disorder were high, taking expert diagnosis using DSM-IV-TR as gold standard. The concordance rate between the INDT-ASD and expert diagnosis for 'ASD group' was 82.52% [Cohen's k=0.89; 95% CI (0.82, 0.97); P=0.001]. The internal consistency of INDT-ASD was 0.96. The convergent validity with CARS (r = 0.73, P= 0.001) and divergent validity with Binet-Kamat Test of intelligence (r = -0.37; P=0.004) were significantly high. INDT-ASD has a 4-factor structure explaining 85.3% of the variance. INDT-ASD has high diagnostic accuracy, adequate content validity, good internal consistency high criterion validity and high to moderate convergent validity and 4-factor construct validity for diagnosis of Autistm spectrum disorder.
Decentralized Network Interdiction Games
2015-12-31
approach is termed as the sample average approximation ( SAA ) method, and theories on the asymptotic convergence to the original problem’s optimal...used in the SAA method’s convergence. While we provided detailed proof of such convergence in [P3], a side benefit of the proof is that it weakens the...conditions required when applying the general SAA approach to the block-structured stochastic programming problem 17. As the conditions known in the
Reliability and validity of the Fear of Intimacy Scale in China.
Ingersoll, Travis S; Norvilitis, Jill M; Zhang, Jie; Jia, Shuhua; Tetewsky, Sheldon
2008-05-01
Participants in China (n = 343) and the United States (n = 283) completed measures to assess the reliability and validity of the Fear of Intimacy Scale (Descutner & Thelen, 1991) with a Chinese population. Internal consistency was strong in both cultures, and the factor structure was also similar between cultures, with confirmatory factor analysis (CFA) identifying three-factor models in both samples. As evidence of convergent validity, the scale was positively correlated with depression and negatively correlated with social support and self-esteem. There were gender differences between cultures, but low levels of femininity were predictive of fear of intimacy in both cultures. The influence of individualism and collectivism varied, with high levels of individualism more predictive of a fear of intimacy in China than in the United States.
Construction and Validation of Afterlife Belief Scale for Muslims.
Ghayas, Saba; Batool, Syeda Shahida
2017-06-01
The purpose of this study was to develop a scale in Urdu language for measuring different dimensions of afterlife belief. The scale was subjected to exploratory and confirmatory factor analysis on a sample of 504 individuals (235 men and 269 women) recruited from different cities in the Punjab, Pakistan. After exploratory and confirmatory factor analysis, 16 items were retained with three well-defined factor structures of afterlife belief: positive, negative, and extinction. The alpha coefficients of the subscales ranged from .65 to .78. Convergent and discriminant validity of the subscales of Afterlife Belief Scale was determined by finding its relationship with the Pleasant Afterlife Belief Scale, the Unpleasant Afterlife Belief Scale, the Anxiety Subscale of DASS, and the Belief in Equitable World Scale. The results support that the newly developed scale has promising validity.
Quaternary tectonic evolution of the Pamir-Tian Shan convergence zone, Northwest China
NASA Astrophysics Data System (ADS)
Thompson Jobe, Jessica Ann; Li, Tao; Chen, Jie; Burbank, Douglas W.; Bufe, Aaron
2017-12-01
The Pamir-Tian Shan collision zone in the western Tarim Basin, northwest China, formed from rapid and ongoing convergence in response to the Indo-Eurasian collision. The arid landscape preserves suites of fluvial terraces crossing structures active since the late Neogene that create fault and fold scarps recording Quaternary deformation. Using geologic and geomorphic mapping, differential GPS surveys of deformed terraces, and optically stimulated luminescence dating, we create a synthesis of the active structures that delineate the timing, rate, and migration of Quaternary deformation during ongoing convergence. New deformation rates on eight faults and folds, when combined with previous studies, highlight the spatial and temporal patterns of deformation within the Pamir-Tian Shan convergence zone during the Quaternary. Terraces spanning 130 to 8 ka record deformation rates between 0.1 and 5.6 mm/yr on individual structures. In the westernmost Tarim Basin, where the Pamir and Tian Shan are already juxtaposed, the fastest rates occur on actively deforming structures at the interface of the Pamir-Tian Shan orogens. Farther east, as the separation between the Pamir-Tian Shan orogens increases, the deformation has not been concentrated on a single structure, but rather has been concurrently distributed across a zone of faults and folds in the Kashi-Atushi fold-and-thrust belt and along the NE Pamir margin, where shortening rates vary on individual structures during the Quaternary. Although numerous structures accommodate the shortening and the locus of deformation shifts during the Quaternary, the total shortening across the western Tarim Basin has remained steady and approximately matches the current geodetic rate of 6-9 mm/yr.
Refining and validating the Social Interaction Anxiety Scale and the Social Phobia Scale.
Carleton, R Nicholas; Collimore, Kelsey C; Asmundson, Gordon J G; McCabe, Randi E; Rowa, Karen; Antony, Martin M
2009-01-01
The Social Interaction Anxiety Scale and Social Phobia Scale are companion measures for assessing symptoms of social anxiety and social phobia. The scales have good reliability and validity across several samples, however, exploratory and confirmatory factor analyses have yielded solutions comprising substantially different item content and factor structures. These discrepancies are likely the result of analyzing items from each scale separately or simultaneously. The current investigation sets out to assess items from those scales, both simultaneously and separately, using exploratory and confirmatory factor analyses in an effort to resolve the factor structure. Participants consisted of a clinical sample (n 5353; 54% women) and an undergraduate sample (n 5317; 75% women) who completed the Social Interaction Anxiety Scale and Social Phobia Scale, along with additional fear-related measures to assess convergent and discriminant validity. A three-factor solution with a reduced set of items was found to be most stable, irrespective of whether the items from each scale are assessed together or separately. Items from the Social Interaction Anxiety Scale represented one factor, whereas items from the Social Phobia Scale represented two other factors. Initial support for scale and factor validity, along with implications and recommendations for future research, is provided. (c) 2009 Wiley-Liss, Inc.
Simple shoulder test and Oxford Shoulder Score: Persian translation and cross-cultural validation.
Naghdi, Soofia; Nakhostin Ansari, Noureddin; Rustaie, Nilufar; Akbari, Mohammad; Ebadi, Safoora; Senobari, Maryam; Hasson, Scott
2015-12-01
To translate, culturally adapt, and validate the simple shoulder test (SST) and Oxford Shoulder Score (OSS) into Persian language using a cross-sectional and prospective cohort design. A standard forward and backward translation was followed to culturally adapt the SST and the OSS into Persian language. Psychometric properties of floor and ceiling effects, construct convergent validity, discriminant validity, internal consistency reliability, test-retest reliability, standard error of the measurement (SEM), smallest detectable change (SDC), and factor structure were determined. One hundred patients with shoulder disorders and 50 healthy subjects participated in the study. The PSST and the POSS showed no missing responses. No floor or ceiling effects were observed. Both the PSST and POSS detected differences between patients and healthy subjects supporting their discriminant validity. Construct convergent validity was confirmed by a very good correlation between the PSST and POSS (r = 0.68). There was high internal consistency for both the PSST (α = 0.73) and the POSS (α = 0.91 and 0.92). Test-retest reliability with 1-week interval was excellent (ICCagreement = 0.94 for PSST and 0.90 for POSS). Factor analyses demonstrated a three-factor solution for the PSST (49.7 % of variance) and a two-factor solution for the POSS (61.6 % of variance). The SEM/SDC was satisfactory for PSST (5.5/15.3) and POSS (6.8/18.8). The PSST and POSS are valid and reliable outcome measures for assessing functional limitations in Persian-speaking patients with shoulder disorders.
Ghassami, Maryam; Asghari, Ali; Shaeeri, Mohammad R; Soltaninejad, Zahra; Safarinejad, Mohammad R
2014-10-01
The present study aimed to investigate the psychometric properties of a Persian version of the Female Sexual Distress Scale-Revised (P-FSDS-R) among a sample of healthy Iranian women. A total of 562 healthy Iranian women completed a battery of questionnaires, including the P-FSDS-R, Depression Anxiety Stress Scales (DASS), Positive and Negative Affect Scales (PANAS) and Locke-Wallace-Marital Adjustment Test (LWMAT). The factor structure and the convergent and divergent validity of the P-FSDS-R were examined, using exploratory and confirmatory factor analysis and Pearson product-moment correlations, respectively. To examine the discriminant validity of the P-FSDS-R, data collected from 562 healthy participants were compared with data from 108 women with sexual problems who completed the P-FSDS-R measure. The results of exploratory and confirmatory factor analyses indicate that the P-FSDS-R is conceptualized within a one - factor model. The results also indicate that the P-FSDS-R has good internal consistency and test-retest reliability. Significant correlations in the predicted directions between the P-FSDS-R scores and the scores of DASS, PANAS and LWMAT support both the convergent and divergent validity of the FSDS-R. The results also indicate that the scores of the P-FSDS-R tests significantly differentiated women with and without sexual problems. In general, these findings support the reliability and the validity of the P-FSDS-R among Iranian women.
Gitlin, Laura N.; Parisi, Jeanine; Huang, Jin; Winter, Laraine; Roth, David L.
2016-01-01
Purpose of study: Examine psychometric properties of Lawton’s Valuation of Life (VOL) scale, a measure of an older adults’ assessment of the perceived value of their lives; and whether ratings differ by race (White, Black/African American) and sex. Design and Methods: The 13-item VOL scale was administered at baseline in 2 separate randomized trials (Advancing Better Living for Elders, ABLE; Get Busy Get Better, GBGB) for a total of 527 older adults. Principal component analyses were applied to a subset of ABLE data (subsample 1) and confirmatory factor analyses were conducted on remaining data (subsample 2 and GBGB). Once the factor structure was identified and confirmed, 2 subscales were created, corresponding to optimism and engagement. Convergent validity of total and subscale scores were examined using measures of depressive symptoms, social support, control-oriented strategies, mastery, and behavioral activation. For discriminant validity, indices of health status, physical function, financial strain, cognitive status, and number of falls were examined. Results: Trial samples (ABLE vs. GBGB) differed by age, race, marital status, education, and employment. Principal component analysis on ABLE subsample 1 (n = 156) yielded two factors subsequently confirmed in confirmatory factor analyses on ABLE subsample 2 (n = 163) and GBGB sample (N = 208) separately. Adequate fit was found for the 2-factor model. Correlational analyses supported strong convergent and discriminant validity. Some statistically significant race and sex differences in subscale scores were found. Implications: VOL measures subjective appraisals of perceived value of life. Consisting of two interrelated subscales, it offers an efficient approach to ascertain personal attributions. PMID:26874189
Convergence of quasiparticle self-consistent G W calculations of transition-metal monoxides
NASA Astrophysics Data System (ADS)
Das, Suvadip; Coulter, John E.; Manousakis, Efstratios
2015-03-01
Finding an accurate ab initio approach for calculating the electronic properties of transition-metal oxides has been a problem for several decades. In this paper, we investigate the electronic structure of the transition-metal monoxides MnO, CoO, and NiO in their undistorted rocksalt structure within a fully iterated quasiparticle self-consistent G W (QPsc G W ) scheme. We study the convergence of the QPsc G W method, i.e., how the quasiparticle energy eigenvalues and wave functions converge as a function of the QPsc G W iterations, and we compare the converged outputs obtained from different starting wave functions. We find that the convergence is slow and that a one-shot G0W0 calculation does not significantly improve the initial eigenvalues and states. It is important to notice that in some cases the "path" to convergence may go through energy band reordering which cannot be captured by the simple initial unperturbed Hamiltonian. When we reach a fully iterated solution, the converged density of states, band gaps, and magnetic moments of these oxides are found to be only weakly dependent on the choice of the starting wave functions and in reasonably good agreement with the experiment. Finally, this approach provides a clear picture of the interplay between the various orbitals near the Fermi level of these simple transition-metal monoxides. The results of these accurate ab initio calculations can provide input for models aiming at describing the low-energy physics in these materials.
Mak, Kwok-Kei; Nam, JeeEun Karin; Kim, Dongil; Aum, Narae; Choi, Jung-Seok; Cheng, Cecilia; Ko, Huei-Chen; Watanabe, Hiroko
2017-03-01
The Korean Scale for Internet Addiction (K-Scale) was developed in Korea for assessing addictive internet behaviors. This study aims to adopt K-Scale and examine its psychometric properties in Japanese adolescents. In 2014, 589 (36.0% boys) high school students (Grade 10-12) from Japan completed a survey, including items of Japanese versions of K-Scale and Smartphone Scale for Smartphone Addiction (S-Scale). Model fit indices of the original four-factor structure, three-factor structure obtained from exploratory factor analysis, and improved two-factor structure of K-Scale were computed using confirmatory factor analysis, with internal reliability of included items reported. The convergent validity of K-Scale was tested against self-rated internet addiction, and S-Scale using multiple regression models. The results showed that a second-order two-factor 13-item structure was the most parsimonious model (NFI=0.919, NNFI=0.935, CFI=0.949, and RMSEA=0.05) with good internal reliability (Cronbach's alpha=0.87). The two factors revealed were "Disturbance of Adaptation and Life Orientation" and "Withdrawal and Tolerance". Moreover, the correlation between internet user classifications defined by K-Scale and self-rating was significant. K-Scale total score was significantly and positively associated with S-Scale total (adjusted R 2 =0.440) and subscale scores (adjusted R 2 =0.439). In conclusion, K-Scale is a valid and reliable assessment scale of internet addiction for Japanese high school students after modifications. Copyright © 2017. Published by Elsevier B.V.
Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans.
Shen, Bing; Dong, Lin; Xiao, Shuhai; Lang, Xianguo; Huang, Kangjun; Peng, Yongbo; Zhou, Chuanming; Ke, Shan; Liu, Pengju
2016-01-07
Molar tooth structures are ptygmatically folded and microspar-filled structures common in early- and mid-Proterozoic (∼2,500-750 million years ago, Ma) subtidal successions, but extremely rare in rocks <750 Ma. Here, on the basis of Mg and S isotopes, we show that molar tooth structures may have formed within sediments where microbial sulphate reduction and methanogenesis converged. The convergence was driven by the abundant production of methyl sulphides (dimethyl sulphide and methanethiol) in euxinic or H2S-rich seawaters that were widespread in Proterozoic continental margins. In this convergence zone, methyl sulphides served as a non-competitive substrate supporting methane generation and methanethiol inhibited anaerobic oxidation of methane, resulting in the buildup of CH4, formation of degassing cracks in sediments and an increase in the benthic methane flux from sediments. Precipitation of crack-filling microspar was driven by methanogenesis-related alkalinity accumulation. Deep ocean ventilation and oxygenation around 750 Ma brought molar tooth structures to an end.
Molar tooth carbonates and benthic methane fluxes in Proterozoic oceans
Shen, Bing; Dong, Lin; Xiao, Shuhai; Lang, Xianguo; Huang, Kangjun; Peng, Yongbo; Zhou, Chuanming; Ke, Shan; Liu, Pengju
2016-01-01
Molar tooth structures are ptygmatically folded and microspar-filled structures common in early- and mid-Proterozoic (∼2,500–750 million years ago, Ma) subtidal successions, but extremely rare in rocks <750 Ma. Here, on the basis of Mg and S isotopes, we show that molar tooth structures may have formed within sediments where microbial sulphate reduction and methanogenesis converged. The convergence was driven by the abundant production of methyl sulphides (dimethyl sulphide and methanethiol) in euxinic or H2S-rich seawaters that were widespread in Proterozoic continental margins. In this convergence zone, methyl sulphides served as a non-competitive substrate supporting methane generation and methanethiol inhibited anaerobic oxidation of methane, resulting in the buildup of CH4, formation of degassing cracks in sediments and an increase in the benthic methane flux from sediments. Precipitation of crack-filling microspar was driven by methanogenesis-related alkalinity accumulation. Deep ocean ventilation and oxygenation around 750 Ma brought molar tooth structures to an end. PMID:26739600
NASA Astrophysics Data System (ADS)
Singh, Shiwangi; Bard, Deborah
2017-01-01
Weak gravitational lensing is an effective tool to map the structure of matter in the universe, and has been used for more than ten years as a probe of the nature of dark energy. Beyond the well-established two-point summary statistics, attention is now turning to methods that use the full statistical information available in the lensing observables, through analysis of the reconstructed shear field. This offers an opportunity to take advantage of powerful deep learning methods for image analysis. We present two early studies that demonstrate that deep learning can be used to characterise features in weak lensing convergence maps, and to identify the underlying cosmological model that produced them.We developed an unsupervised Denoising Convolutional Autoencoder model in order to learn an abstract representation directly from our data. This model uses a convolution-deconvolution architecture, which is fed with input data (corrupted with binomial noise to prevent over-fitting). Our model effectively trains itself to minimize the mean-squared error between the input and the output using gradient descent, resulting in a model which, theoretically, is broad enough to tackle other similarly structured problems. Using this model we were able to successfully reconstruct simulated convergence maps and identify the structures in them. We also determined which structures had the highest “importance” - i.e. which structures were most typical of the data. We note that the structures that had the highest importance in our reconstruction were around high mass concentrations, but were highly non-Gaussian.We also developed a supervised Convolutional Neural Network (CNN) for classification of weak lensing convergence maps from two different simulated theoretical models. The CNN uses a softmax classifier which minimizes a binary cross-entropy loss between the estimated distribution and true distribution. In other words, given an unseen convergence map the trained CNN determines probabilistically which theoretical model fits the data best. This preliminary work demonstrates that we can classify the cosmological model that produced the convergence maps with 80% accuracy.
On the convergence and accuracy of the FDTD method for nanoplasmonics.
Lesina, Antonino Calà; Vaccari, Alessandro; Berini, Pierre; Ramunno, Lora
2015-04-20
Use of the Finite-Difference Time-Domain (FDTD) method to model nanoplasmonic structures continues to rise - more than 2700 papers have been published in 2014 on FDTD simulations of surface plasmons. However, a comprehensive study on the convergence and accuracy of the method for nanoplasmonic structures has yet to be reported. Although the method may be well-established in other areas of electromagnetics, the peculiarities of nanoplasmonic problems are such that a targeted study on convergence and accuracy is required. The availability of a high-performance computing system (a massively parallel IBM Blue Gene/Q) allows us to do this for the first time. We consider gold and silver at optical wavelengths along with three "standard" nanoplasmonic structures: a metal sphere, a metal dipole antenna and a metal bowtie antenna - for the first structure comparisons with the analytical extinction, scattering, and absorption coefficients based on Mie theory are possible. We consider different ways to set-up the simulation domain, we vary the mesh size to very small dimensions, we compare the simple Drude model with the Drude model augmented with two critical points correction, we compare single-precision to double-precision arithmetic, and we compare two staircase meshing techniques, per-component and uniform. We find that the Drude model with two critical points correction (at least) must be used in general. Double-precision arithmetic is needed to avoid round-off errors if highly converged results are sought. Per-component meshing increases the accuracy when complex geometries are modeled, but the uniform mesh works better for structures completely fillable by the Yee cell (e.g., rectangular structures). Generally, a mesh size of 0.25 nm is required to achieve convergence of results to ∼ 1%. We determine how to optimally setup the simulation domain, and in so doing we find that performing scattering calculations within the near-field does not necessarily produces large errors but reduces the computational resources required.
NASA Astrophysics Data System (ADS)
Sang, Xiahan
Intermetallics offer unique property combinations often superior to those of more conventional solid solution alloys of identical composition. Understanding of bonding in intermetallics would greatly accelerate development of intermetallics for advanced and high performance engineering applications. Tetragonal intermetallics L10 ordered TiAl, FePd and FePt are used as model systems to experimentally measure their electron densities using quantitative convergent beam electron diffraction (QCBED) method and then compare details of the 3d-4d (FePd) and 3d-5d (FePt) electron interactions to elucidate their role on properties of the respective ferromagnetic L10-ordered intermetallics FePd and FePt. A new multi-beam off-zone axis condition QCBED method has been developed to increase sensitivity of CBED patterns to change of structure factors and the anisotropic Debye-Waller (DW) factors. Unprecedented accuracy and precision in structure and DW factor measurements has been achieved by acquiring CBED patterns using beam-sample geometry that ensures strong dynamical interaction between the fast electrons and the periodic potential in the crystalline samples. This experimental method has been successfully applied to diamond cubic Si, and chemically ordered B2 cubic NiAl, tetragonal L10 ordered TiAl and FePd. The accurate and precise experimental DW and structure factors for L10 TiAl and FePd allow direct evaluation of computer calculations using the current state of the art density functional theory (DFT) based electron structure modeling. The experimental electron density difference map of L1 0 TiAl shows that the DFT calculations describe bonding to a sufficient accuracy for s- and p- electrons interaction, e. g., the Al-layer. However, it indicate significant quantitative differences to the experimental measurements for the 3d-3d interactions of the Ti atoms, e.g. in the Ti layers. The DFT calculations for L10 FePd also show that the current DFT approximations insufficiently describe the interaction between Fe-Fe (3d-3d), Fe-Pd (3d-4d) and Pd-Pd (4d-4d) electrons, which indicates the necessity to evaluate applicability of different DFT approximations, and also provides experimental data for the development of new DFT approximation that better describes transition metal based intermetallic systems.
An efficient strongly coupled immersed boundary method for deforming bodies
NASA Astrophysics Data System (ADS)
Goza, Andres; Colonius, Tim
2016-11-01
Immersed boundary methods treat the fluid and immersed solid with separate domains. As a result, a nonlinear interface constraint must be satisfied when these methods are applied to flow-structure interaction problems. This typically results in a large nonlinear system of equations that is difficult to solve efficiently. Often, this system is solved with a block Gauss-Seidel procedure, which is easy to implement but can require many iterations to converge for small solid-to-fluid mass ratios. Alternatively, a Newton-Raphson procedure can be used to solve the nonlinear system. This typically leads to convergence in a small number of iterations for arbitrary mass ratios, but involves the use of large Jacobian matrices. We present an immersed boundary formulation that, like the Newton-Raphson approach, uses a linearization of the system to perform iterations. It therefore inherits the same favorable convergence behavior. However, we avoid large Jacobian matrices by using a block LU factorization of the linearized system. We derive our method for general deforming surfaces and perform verification on 2D test problems of flow past beams. These test problems involve large amplitude flapping and a wide range of mass ratios. This work was partially supported by the Jet Propulsion Laboratory and Air Force Office of Scientific Research.
A Symmetric Positive Definite Formulation for Monolithic Fluid Structure Interaction
2010-08-09
more likely to converge than simply iterating the partitioned approach to convergence in a simple Gauss - Seidel manner. Our approach allows the use of...conditions in a second step. These approaches can also be iterated within a given time step for increased stability, noting that in the limit if one... converges one obtains a monolithic (albeit expensive) approach. Other approaches construct strongly coupled systems and then solve them in one of several
Spanish adaptation of the internal functioning of the Work Teams Scale (QFI-22).
Ficapal-Cusí, Pilar; Boada-Grau, Joan; Torrent-Sellens, Joan; Vigil-Colet, Andreu
2014-05-01
The aim of this article is to develop the Spanish adaptation of the internal functioning of Work Teams Scale (QFI-22). The scale was adapted from the French version, and was applied to a sample of 1,055 employees working for firms operating in Spain. The article analyses the internal structure (exploratory and confirmatory factor analysis) and internal consistency, and provides convergent validity evidence of the scale. The QFI-22 scale shows the same internal structure as the original. Factor analysis confirmed the existence of two factors: interpersonal support and team work management, with good internal consistency coefficients (α1 = .93, α2 = .92). Regarding validity evidence, the QFI-22 scale has significant correlations with other correlates and alternative scales used for comparison purposes. The two factors correlated positively with team vision, participation safety, task orientation and support for innovation (Team Climate Inventory, TCI scale), with progressive culture (Organisational Culture, X-Y scale), and with creating change, customer focus and organisational learning (Denison Organizational Culture Survey, DOCS scale). In contrast, the two factors correlated negatively with traditional culture (X-Y scale). The QFI-22 scale is a useful instrument for assessing the internal functioning of work teams.
Abdul Khaiyom, Jamilah Hanum; Mukhtar, Firdaus; Ibrahim, Normala; Mohd Sidik, Sherina; Oei, Tian Po Sumantri
2016-12-01
The Catastrophic Cognitions Questionnaire-Modified (CCQ-M) is a common instrument for measuring catastrophic thoughts. In some countries, however, CCQ-M still poses concerns following the lack of appropriate validation among their populations. The current study aimed to examine the factor structure of the CCQ-M, the reliability, and the validity in community samples in Malaysia. The Malay version of CCQ-M and additional measures assessing the symptoms and cognitions relevant to anxiety disorders were completed by 682 university students and general community. Exploratory factor analysis revealed a two-factor structure accounting for 62.2% of the total variance. Confirmatory factor analysis confirmed the two-factor model by deleting four items. The Cronbach's alpha coefficients for the total and the two subscales were .94, .90, and .92, respectively. Test-retest reliability analysis was conducted on 82 university students in the interval period of 14 days, and the result was r = .58. Evidence supported the concurrent, convergent, and discriminant validity. In conclusion, the 17-item CCQ-M-Malaysia is a valid and reliable instrument for assessing catastrophic cognitions among Malaysian populations. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Does healthcare financing converge? Evidence from eight OECD countries.
Chen, Wen-Yi
2013-12-01
This study investigated the convergence of healthcare financing across eight OECD countries during 1960-2009 for the first time. The panel stationary test incorporating both shapes of multiple structural breaks (i.e., sharp drifts and smooth transition shifts) and cross-sectional dependence was used to provide reliable evidence of convergence in healthcare financing. Our results suggested that the public share of total healthcare financing in eight OECD countries has exhibited signs of convergence towards that of the US. The convergence of healthcare financing not only reflected a decline in the share of public healthcare financing in these eight OECD countries but also exhibited an upward trend in the share of public healthcare financing in the US over the period of 1960-2009.
Calcium-independent metal-ion catalytic mechanism of anthrax edema factor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shen, Yuequan; Zhukovskaya, Natalia L.; Guo, Qing
2009-11-18
Edema factor (EF), a key anthrax exotoxin, has an anthrax protective antigen-binding domain (PABD) and a calmodulin (CaM)-activated adenylyl cyclase domain. Here, we report the crystal structures of CaM-bound EF, revealing the architecture of EF PABD. CaM has N- and C-terminal domains and each domain can bind two calcium ions. Calcium binding induces the conformational change of CaM from closed to open. Structures of the EF-CaM complex show how EF locks the N-terminal domain of CaM into a closed conformation regardless of its calcium-loading state. This represents a mechanism of how CaM effector alters the calcium affinity of CaM andmore » uncouples the conformational change of CaM from calcium loading. Furthermore, structures of EF-CaM complexed with nucleotides show that EF uses two-metal-ion catalysis, a prevalent mechanism in DNA and RNA polymerases. A histidine (H351) further facilitates the catalysis of EF by activating a water to deprotonate 3'OH of ATP. Mammalian adenylyl cyclases share no structural similarity with EF and they also use two-metal-ion catalysis, suggesting the catalytic mechanism-driven convergent evolution of two structurally diverse adenylyl cyclases.« less
Convergence analysis of two-node CMFD method for two-group neutron diffusion eigenvalue problem
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeong, Yongjin; Park, Jinsu; Lee, Hyun Chul
2015-12-01
In this paper, the nonlinear coarse-mesh finite difference method with two-node local problem (CMFD2N) is proven to be unconditionally stable for neutron diffusion eigenvalue problems. The explicit current correction factor (CCF) is derived based on the two-node analytic nodal method (ANM2N), and a Fourier stability analysis is applied to the linearized algorithm. It is shown that the analytic convergence rate obtained by the Fourier analysis compares very well with the numerically measured convergence rate. It is also shown that the theoretical convergence rate is only governed by the converged second harmonic buckling and the mesh size. It is also notedmore » that the convergence rate of the CCF of the CMFD2N algorithm is dependent on the mesh size, but not on the total problem size. This is contrary to expectation for eigenvalue problem. The novel points of this paper are the analytical derivation of the convergence rate of the CMFD2N algorithm for eigenvalue problem, and the convergence analysis based on the analytic derivations.« less
Discrete-Time Deterministic $Q$ -Learning: A Novel Convergence Analysis.
Wei, Qinglai; Lewis, Frank L; Sun, Qiuye; Yan, Pengfei; Song, Ruizhuo
2017-05-01
In this paper, a novel discrete-time deterministic Q -learning algorithm is developed. In each iteration of the developed Q -learning algorithm, the iterative Q function is updated for all the state and control spaces, instead of updating for a single state and a single control in traditional Q -learning algorithm. A new convergence criterion is established to guarantee that the iterative Q function converges to the optimum, where the convergence criterion of the learning rates for traditional Q -learning algorithms is simplified. During the convergence analysis, the upper and lower bounds of the iterative Q function are analyzed to obtain the convergence criterion, instead of analyzing the iterative Q function itself. For convenience of analysis, the convergence properties for undiscounted case of the deterministic Q -learning algorithm are first developed. Then, considering the discounted factor, the convergence criterion for the discounted case is established. Neural networks are used to approximate the iterative Q function and compute the iterative control law, respectively, for facilitating the implementation of the deterministic Q -learning algorithm. Finally, simulation results and comparisons are given to illustrate the performance of the developed algorithm.
Maisuradze, Gia G; Leitner, David M
2007-05-15
Dihedral principal component analysis (dPCA) has recently been developed and shown to display complex features of the free energy landscape of a biomolecule that may be absent in the free energy landscape plotted in principal component space due to mixing of internal and overall rotational motion that can occur in principal component analysis (PCA) [Mu et al., Proteins: Struct Funct Bioinfo 2005;58:45-52]. Another difficulty in the implementation of PCA is sampling convergence, which we address here for both dPCA and PCA using a tetrapeptide as an example. We find that for both methods the sampling convergence can be reached over a similar time. Minima in the free energy landscape in the space of the two largest dihedral principal components often correspond to unique structures, though we also find some distinct minima to correspond to the same structure. 2007 Wiley-Liss, Inc.
Trauma Coping Self-Efficacy: A Context Specific Self-Efficacy Measure for Traumatic Stress
Benight, Charles C.; Shoji, Kotaro; James, Lori E.; Waldrep, Edward E.; Delahanty, Douglas L.; Cieslak, Roman
2015-01-01
The psychometric properties of a Trauma Coping Self-Efficacy (CSE-T) scale that assesses general trauma-related coping self-efficacy perceptions were assessed. Measurement equivalence was assessed using several different samples: hospitalized trauma patients (n1 = 74, n2 = 69, n3 = 60), three samples of disaster survivors (n1 = 273, n2 = 227, n3 = 138), and trauma exposed college students (N = 242). This is the first multi-sample evaluation of the psychometric properties for a general trauma-related CSE measure. Results showed that a brief and parsimonious 9-item version of the CSE performed well across the samples with a robust factor structure; factor structure and factor loadings were similar across study samples. The 9-item scale CSE-T demonstrated measurement equivalence across samples indicating that the underlying concept of general post-traumatic CSE is organized in a similar manner in the different trauma-exposed groups. These results offer strong support for cross-event construct validity of the CSE-T scale. Associations of the CSE-T with important expected covariates showed significant evidence for convergent validity. Finally, discriminant validity was also supported. Replication of the factor structure, internal reliability, and other evidence for construct validity is a critical next step for future research. PMID:26524542
Shisslak, C M; Renger, R; Sharpe, T; Crago, M; McKnight, K M; Gray, N; Bryson, S; Estes, L S; Parnaby, O G; Killen, J; Taylor, C B
1999-03-01
To describe the development, test-retest reliability, internal consistency, and convergent validity of the McKnight Risk Factor Survey-III (MRFS-III). The MRFS-III was designed to assess a number of potential risk and protective factors for the development of disordered eating in preadolescent and adolescent girls. Several versions of the MRFS were pilot tested before the MRFS-III was administered to a sample of 651 4th through 12th- grade girls to establish its psychometric properties. Most of the test-retest reliability coefficients of individual items on the MRFS-III were r > .40. Alpha coefficients for each risk and protective factor domain on the MRFS-III were also computed. The majority of these coefficients were r > .60. High convergent validity coefficients were obtained for specific items on the MRFS-III and measures of self-esteem (Rosenberg Self-Esteem Scale) and weight concerns (Weight Concerns Scale). The test-retest reliability, internal consistency, and convergent validity of the MRFS-III suggest that it is a useful new instrument to assess potential risk and protective factors for the development of disordered eating in preadolescent and adolescent girls.
NASA Astrophysics Data System (ADS)
Walton, M. A. L.; Miller, N. C.; Brothers, D. S.; Kluesner, J.; Haeussler, P. J.; Conrad, J. E.; Andrews, B. D.; Ten Brink, U. S.
2017-12-01
The Queen Charlotte Fault (QCF) is a fast-moving ( 53 mm/yr) transform plate boundary fault separating the Pacific Plate from the North American Plate along western Canada and southeastern Alaska. New high-resolution bathymetric data along the fault show that the QCF main trace accommodates nearly all strike-slip plate motion along a single narrow deformation zone, though questions remain about how and where smaller amounts of oblique convergence are accommodated along-strike. Obliquity and convergence rates are highest in the south, where the 2012 Haida Gwaii, British Columbia MW 7.8 thrust earthquake was likely caused by Pacific underthrusting. In the north, where obliquity is lower, aftershocks from the 2013 Craig, Alaska MW 7.5 strike-slip earthquake also indicate active convergent deformation on the Pacific (west) side of the plate boundary. Off-fault structures previously mapped in legacy crustal-scale seismic profiles may therefore be accommodating part of the lesser amounts of Quaternary convergence north of Haida Gwaii. Between 2015 and 2017, the USGS acquired more than 8,000 line-km of offshore high-resolution multichannel seismic (MCS) data along the QCF to better understand plate boundary deformation. The new MCS data show evidence for Quaternary deformation associated with a series of elongate ridges located within 30 km of the QCF main trace on the Pacific side. These ridges are anticlinal structures flanked by growth faults, with recent deformation and active fluid flow characterized by seafloor scarps and seabed gas seeps at ridge crests. Structural and morphological evidence for contractional deformation decreases northward along the fault, consistent with a decrease in Pacific-North America obliquity along the plate boundary. Preliminary interpretations suggest that plate boundary transpression may be partitioned into distinctive structural domains, in which convergent stress is accommodated by margin-parallel thrust faulting, folding, and ridge formation within the Pacific Plate, with strike-slip faulting localized to the primary trace of the QCF. Contractional structures may be occupying zones of pre-existing crustal weakness and/or re-activated fabrics in the oceanic crust, possibly explaining strain partitioning behavior in areas with a low convergence angle (<15°).
The structure of social exchange in self-help support groups: development of a measure.
Brown, Louis D; Tang, Xiaohui; Hollman, Ruth L
2014-03-01
Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics.
Reliability and Validity of the Visual, Musculoskeletal, and Balance Complaints Questionnaire.
Lundqvist, Lars-Olov; Zetterlund, Christina; Richter, Hans O
2016-09-01
To evaluate the reliability and validity of the 15-item Visual, Musculoskeletal, and Balance Complaints Questionnaire (VMB) for people with visual impairments, using confirmatory factor analysis (CFA) and with Rasch analysis for use as an outcome measure. Two studies evaluated the VMB. In Study 1, VMB data were collected from 1249 out of 3063 individuals between 18 and 104 years old who were registered at a low vision center. CFA evaluated VMB factor structure and Rasch analysis evaluated VMB scale properties. In Study 2, a subsample of 52 individuals between 27 and 67 years old with visual impairments underwent further measurements. Visual clinical assessments, neck/scapular pain, and balance assessments were collected to evaluate the convergent validity of the VMB (i.e. the domain relationship with other, theoretically predicted measures). CFA supported the a priori three-factor structure of the VMB. The factor loadings of the items on their respective domains were all statistically significant. Rasch analysis indicated disordered categories and the original 10-point scale was subsequently replaced with a 5-point scale. Each VMB domain fitted the Rasch model, showing good metric properties, including unidimensionality (explained variances ≥66% and eigenvalues <1.9), person separation (1.86 to 2.29), reliability (0.87 to 0.94), item fit (infit MnSq's >0.72 and outfit MnSq's <1.47), targeting (0.30 to 0.50 logits), and insignificant differential item functioning (all DIFs but one <0.50 logits) from gender, age, and visual status. The three VMB domains correlated significantly with relevant visual, musculoskeletal, and balance assessments, demonstrating adequate convergent validity of the VMB. The VMB is a simple, inexpensive, and quick yet reliable and valid way to screen and evaluate concurrent visual, musculoskeletal, and balance complaints, with contribution to epidemiological and intervention research and potential clinical implications for the field of health services and low vision rehabilitation.
Reliability and Validity of the Visual, Musculoskeletal, and Balance Complaints Questionnaire
Lundqvist, Lars-Olov; Zetterlund, Christina; Richter, Hans O.
2016-01-01
ABSTRACT Purpose To evaluate the reliability and validity of the 15-item Visual, Musculoskeletal, and Balance Complaints Questionnaire (VMB) for people with visual impairments, using confirmatory factor analysis (CFA) and with Rasch analysis for use as an outcome measure. Methods Two studies evaluated the VMB. In Study 1, VMB data were collected from 1249 out of 3063 individuals between 18 and 104 years old who were registered at a low vision center. CFA evaluated VMB factor structure and Rasch analysis evaluated VMB scale properties. In Study 2, a subsample of 52 individuals between 27 and 67 years old with visual impairments underwent further measurements. Visual clinical assessments, neck/scapular pain, and balance assessments were collected to evaluate the convergent validity of the VMB (i.e. the domain relationship with other, theoretically predicted measures). Results CFA supported the a priori three-factor structure of the VMB. The factor loadings of the items on their respective domains were all statistically significant. Rasch analysis indicated disordered categories and the original 10-point scale was subsequently replaced with a 5-point scale. Each VMB domain fitted the Rasch model, showing good metric properties, including unidimensionality (explained variances ≥66% and eigenvalues <1.9), person separation (1.86 to 2.29), reliability (0.87 to 0.94), item fit (infit MnSq’s >0.72 and outfit MnSq’s <1.47), targeting (0.30 to 0.50 logits), and insignificant differential item functioning (all DIFs but one <0.50 logits) from gender, age, and visual status. The three VMB domains correlated significantly with relevant visual, musculoskeletal, and balance assessments, demonstrating adequate convergent validity of the VMB. Conclusions The VMB is a simple, inexpensive, and quick yet reliable and valid way to screen and evaluate concurrent visual, musculoskeletal, and balance complaints, with contribution to epidemiological and intervention research and potential clinical implications for the field of health services and low vision rehabilitation. PMID:27309524
NASA Astrophysics Data System (ADS)
Petri, Andrea; May, Morgan; Haiman, Zoltán
2016-09-01
Weak gravitational lensing is becoming a mature technique for constraining cosmological parameters, and future surveys will be able to constrain the dark energy equation of state w . When analyzing galaxy surveys, redshift information has proven to be a valuable addition to angular shear correlations. We forecast parameter constraints on the triplet (Ωm,w ,σ8) for a LSST-like photometric galaxy survey, using tomography of the shear-shear power spectrum, convergence peak counts and higher convergence moments. We find that redshift tomography with the power spectrum reduces the area of the 1 σ confidence interval in (Ωm,w ) space by a factor of 8 with respect to the case of the single highest redshift bin. We also find that adding non-Gaussian information from the peak counts and higher-order moments of the convergence field and its spatial derivatives further reduces the constrained area in (Ωm,w ) by factors of 3 and 4, respectively. When we add cosmic microwave background parameter priors from Planck to our analysis, tomography improves power spectrum constraints by a factor of 3. Adding moments yields an improvement by an additional factor of 2, and adding both moments and peaks improves by almost a factor of 3 over power spectrum tomography alone. We evaluate the effect of uncorrected systematic photometric redshift errors on the parameter constraints. We find that different statistics lead to different bias directions in parameter space, suggesting the possibility of eliminating this bias via self-calibration.
Weeks, Justin W
2015-01-01
Wang, Hsu, Chiu, and Liang (2012, Journal of Anxiety Disorders, 26, 215-224) recently proposed a hierarchical model of social interaction anxiety and depression to account for both the commonalities and distinctions between these conditions. In the present paper, this model was extended to more broadly encompass the symptoms of social anxiety disorder, and replicated in a large unselected, undergraduate sample (n = 585). Structural equation modeling (SEM) and hierarchical regression analyses were employed. Negative affect and positive affect were conceptualized as general factors shared by social anxiety and depression; fear of negative evaluation (FNE) and disqualification of positive social outcomes were operationalized as specific factors, and fear of positive evaluation (FPE) was operationalized as a factor unique to social anxiety. This extended hierarchical model explicates structural relationships among these factors, in which the higher-level, general factors (i.e., high negative affect and low positive affect) represent vulnerability markers of both social anxiety and depression, and the lower-level factors (i.e., FNE, disqualification of positive social outcomes, and FPE) are the dimensions of specific cognitive features. Results from SEM and hierarchical regression analyses converged in support of the extended model. FPE is further supported as a key symptom that differentiates social anxiety from depression.
Convergence of temperate and tropical stream fish assemblages
The hypothesis of convergence takes the deterministic view that community (or assemblage) structure can be predicted from the environment, and that the environment is expected to drive evolution in a predictable direction. Here we present results of a comparative study of freshwa...
Nonlinear convergence active vibration absorber for single and multiple frequency vibration control
NASA Astrophysics Data System (ADS)
Wang, Xi; Yang, Bintang; Guo, Shufeng; Zhao, Wenqiang
2017-12-01
This paper presents a nonlinear convergence algorithm for active dynamic undamped vibration absorber (ADUVA). The damping of absorber is ignored in this algorithm to strengthen the vibration suppressing effect and simplify the algorithm at the same time. The simulation and experimental results indicate that this nonlinear convergence ADUVA can help significantly suppress vibration caused by excitation of both single and multiple frequency. The proposed nonlinear algorithm is composed of equivalent dynamic modeling equations and frequency estimator. Both the single and multiple frequency ADUVA are mathematically imitated by the same mechanical structure with a mass body and a voice coil motor (VCM). The nonlinear convergence estimator is applied to simultaneously satisfy the requirements of fast convergence rate and small steady state frequency error, which are incompatible for linear convergence estimator. The convergence of the nonlinear algorithm is mathematically proofed, and its non-divergent characteristic is theoretically guaranteed. The vibration suppressing experiments demonstrate that the nonlinear ADUVA can accelerate the convergence rate of vibration suppressing and achieve more decrement of oscillation attenuation than the linear ADUVA.
Schmitt, Andreas; Gahr, Annika; Hermanns, Norbert; Kulzer, Bernhard; Huber, Jörg; Haak, Thomas
2013-08-13
Though several questionnaires on self-care and regimen adherence have been introduced, the evaluations do not always report consistent and substantial correlations with measures of glycaemic control. Small ability to explain variance in HbA1c constitutes a significant limitation of an instrument's use for scientific purposes as well as clinical practice. In order to assess self-care activities which can predict glycaemic control, the Diabetes Self-Management Questionnaire (DSMQ) was designed. A 16 item questionnaire to assess self-care activities associated with glycaemic control was developed, based on theoretical considerations and a process of empirical improvements. Four subscales, 'Glucose Management' (GM), 'Dietary Control' (DC), 'Physical Activity' (PA), and 'Health-Care Use' (HU), as well as a 'Sum Scale' (SS) as a global measure of self-care were derived. To evaluate its psychometric quality, 261 patients with type 1 or 2 diabetes were assessed with the DSMQ and an established analogous scale, the Summary of Diabetes Self-Care Activities Measure (SDSCA). The DSMQ's item and scale characteristics as well as factorial and convergent validity were analysed, and its convergence with HbA1c was compared to the SDSCA. The items showed appropriate characteristics (mean item-total-correlation: 0.46 ± 0.12; mean correlation with HbA1c: -0.23 ± 0.09). Overall internal consistency (Cronbach's alpha) was good (0.84), consistencies of the subscales were acceptable (GM: 0.77; DC: 0.77; PA: 0.76; HU: 0.60). Principal component analysis indicated a four factor structure and confirmed the designed scale structure. Confirmatory factor analysis indicated appropriate fit of the four factor model. The DSMQ scales showed significant convergent correlations with their parallel SDSCA scales (GM: 0.57; DC: 0.52; PA: 0.58; HU: n/a; SS: 0.57) and HbA1c (GM: -0.39; DC: -0.30; PA: -0.15; HU: -0.22; SS: -0.40). All correlations with HbA1c were significantly stronger than those obtained with the SDSCA. This study provides preliminary evidence that the DSMQ is a reliable and valid instrument and enables an efficient assessment of self-care behaviours associated with glycaemic control. The questionnaire should be valuable for scientific analyses as well as clinical use in both type 1 and type 2 diabetes patients.
NASA Astrophysics Data System (ADS)
Pronin, A. A.
The structures of the Lakshmi Planum and its surrounding mountains are described. Special attention is given to the origin of the Lakshmi structure. The compressional deformations on its periphery are explained by seeing the Lakshimi strucutre as a locus of convergence, and the volcanic activity of the central part of the structure is explained by the melting of the bottom of the crust at the place of its convergency thickening. It is noted that the characteristics of the Lakshmi Planum and it bounding mountains suggest that this ensemble is a giant hot-spot structure with the intensive volcanism and radial tectonic spreading, leading to the piling up of the crust material at the structure periphery. A tectonic scheme of the Lakshmi structure formation is presented.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Bo; Jiang, Yunchun; Yang, Jiayan
Taking advantage of the high spatiotemporal resolution observations from the Atmospheric Imaging Assembly (AIA) and the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory, we present rare observations of the rapid formation of a filament caused by magnetic reconnection between two sets of dark threadlike structures. The two sets of dark threadlike structures belong to distinct flux systems with their adjacent ends anchored in an opposite-polarity magnetic field region, where the calculated photospheric velocity field shows that converging flows dominate there. Due to the converging flows, opposite-polarity magnetic flux converged and then canceled, leading to the formation ofmore » extreme ultraviolet (EUV) brightening that spread in opposite directions along the spine of the dark threadlike structures. Meanwhile, very weak remote brightening in the other terminals of the dark threadlike structures, as well as EUV loops, which rooted in the opposite-polarity magnetic field region, appeared. In addition, all of the AIA Fe line observations reveal that a flux rope was formed and underwent a rolling motion during the fadeaway of the EUV brightening. Soon after, as the EUV brightening disappeared, a filament that is very likely composed of two sets of intertwined dark threadlike structures was formed. Via differential emission measure (EM) analysis, it is found that both the EM and temperature of the plasma around the flux-canceling site increased during the brightening, implying that there, magnetic reconnection may occur to heat the plasma. These observations provide evidence that the filament is formed by magnetic reconnection associated with flux convergence and cancellation, and the magnetic structure of the filament is most likely a flux rope.« less
Anger Rumination Scale: Validation in Mexico.
Ortega Andrade, Norma; Alcázar-Olán, Raúl; Matías, Oscar Mariano; Rivera Guerrero, Ana; Domínguez Espinosa, Alejandra
2017-01-18
The aim of the study was to assess the validity of the Anger Rumination Scale (ARS; Sukhodolsky, Golub, & Cromwell, 2001) in a Mexican sample (n = 700, M age = 38.6, SD = 12.42). Through confirmatory factor analysis and using modification indices, the four-factor structure of the original scale was replicated: angry afterthoughts, thoughts of revenge, angry memories, and understanding of causes. In addition, the four-factor model had better goodness of fit indices than rival models with three and two factors. Alpha reliabilities were acceptable (.72 -.89). ARS results correlated with measures of state anger, trait anger, anger expression, and anger control (negatively); correlations were significant (ps < .001) ARS outcomes also correlated (ps < .001) with physical and verbal aggression, hostility, anger, and emotion suppression, suggesting convergent validity. Men reported more thoughts of revenge than women (p < .001; Eta squared = .026), but there was no evidence of gender differences on the other anger rumination scales, or in total scores.
Measuring hope among families impacted by cognitive impairment
Hunsaker, Amanda E.; Terhorst, Lauren; Gentry, Amanda; Lingler, Jennifer H.
2014-01-01
The current exploratory investigation aims to establish the reliability and validity of a hope measure, the Herth Hope Index (HHI), among families impacted by early cognitive impairment (N=96). Exploratory factor analysis was used to examine the dimensionality of the measure. Bivariate analyses were used to examine construct validity. The sample had moderately high hope scores. A two-factor structure emerged from the factor analysis, explaining 51.44% of the variance. Both factors exhibited strong internal consistency (Cronbach’s alphas ranged from .83 to .86). Satisfaction with social support was positively associated with hope, supporting convergent validity. Neurocognitive status, illness insight and depression were not associated with hope, indicating discriminant validity. Families impacted by cognitive impairment may maintain hope in the face of a potentially progressive illness, regardless of cognitive status. The HHI can be utilized as a reliable and valid measure of hope by practitioners providing support to families impacted by cognitive impairment. PMID:24784938
Psychopathy in Bulgaria: The cross-cultural generalizability of the Hare Psychopathy Checklist
Wilson, Michael J.; Abramowitz, Carolyn; Vasilev, Georgi; Bozgunov, Kiril; Vassileva, Jasmin
2014-01-01
The generalizability of the psychopathy construct to Eastern European cultures has not been well-studied, and no prior studies have evaluated psychopathy in non-offender samples from this population. The current validation study examines the factor structure, internal consistency, and external validity of the Bulgarian translation of the Hare Psychopathy Checklist: Screening Version. Two hundred sixty-two Bulgarian adults from the general community were assessed, of which 185 had a history of substance dependence. Confirmatory factor analysis indicated good fit for the two-, three-, and four-factor models of psychopathy. Zero-order and partial correlation analyses were conducted between the two factors of psychopathy and criterion measures of antisocial behavior, internalizing and externalizing psychopathology, personality traits, addictive disorders and demographic characteristics. Relationships to external variables provided evidence for the convergent and discriminant validity of the psychopathy construct in a Bulgarian community sample. PMID:25313268
Merlin, Fabrício Kurman; Pereira, Vera Lúciaduarte do Valle; Pacheco, Waldemar
2012-01-01
Organizations are part of an environment in which they are pressured to meet society's demands and acting in a sustainable way. In an attempt to meet such demands, organizations make use of various management tools, among which, ISO standards are used. Although there are evidences of contributions provided by these standards, it is questionable whether its parameters converge for a possible induction for sustainable development in organizations. This work presents a theoretical study, designed on structuralism world view, descriptive and deductive method, which aims to analyze the convergence of management tools' parameters in ISO standards. In order to support the analysis, a generic framework for possible convergence was developed, based on systems approach, linking five ISO standards (ISO 9001, ISO 14001, OHSAS 18001, ISO 31000 and ISO 26000) with sustainable development and positioning them according to organization levels (strategic, tactical and operational). The structure was designed based on Brundtland report concept. The analysis was performed exploring the generic framework for possible convergence based on Nadler and Tushman model. The results found the standards can contribute to a possible sustainable development induction in organizations, as long as they meet certain minimum conditions related to its strategic alignment.
An adaptively refined XFEM with virtual node polygonal elements for dynamic crack problems
NASA Astrophysics Data System (ADS)
Teng, Z. H.; Sun, F.; Wu, S. C.; Zhang, Z. B.; Chen, T.; Liao, D. M.
2018-02-01
By introducing the shape functions of virtual node polygonal (VP) elements into the standard extended finite element method (XFEM), a conforming elemental mesh can be created for the cracking process. Moreover, an adaptively refined meshing with the quadtree structure only at a growing crack tip is proposed without inserting hanging nodes into the transition region. A novel dynamic crack growth method termed as VP-XFEM is thus formulated in the framework of fracture mechanics. To verify the newly proposed VP-XFEM, both quasi-static and dynamic cracked problems are investigated in terms of computational accuracy, convergence, and efficiency. The research results show that the present VP-XFEM can achieve good agreement in stress intensity factor and crack growth path with the exact solutions or experiments. Furthermore, better accuracy, convergence, and efficiency of different models can be acquired, in contrast to standard XFEM and mesh-free methods. Therefore, VP-XFEM provides a suitable alternative to XFEM for engineering applications.
Experimental viscous fingering in a tapered radial Hele-Shaw cell
NASA Astrophysics Data System (ADS)
Bongrand, Gregoire; Tsai, Peichun Amy; Complex Fludis Group Team
2017-11-01
The fluid-fluid displacement in porous media is a common process that finds direct applications in various fields, such as enhanced oil recovery and geological CO2 sequestration. In this work, we experimentally investigate the influence of converging cells on viscous fingering instabilities using a radially-tapered cell. For air displacing oil, in contrast to the classical Saffman-Taylor fingering, our results show that a converging gradient in a radial propagation can provide a stabilizing effect and hinder fingering. For a fixed gap gradient and thickness, with increasing injection rates we find a stable displacement under small flow rates, whereas unstable fingering occurs above a certain threshold. We further investigate this critical flow rate delineating the stable and unstable regimes for different gap gradients. These results reveal that the displacement efficiency not only depends on the fluid properties but also on the interfacial velocity and channel structure. The latter factors provide a useful and convenient control to either trigger or inhibit fingering instability. NSERC Discovery, Accelerator, and CRC programs.
Mainprize, Iain L; Beniac, Daniel R; Falkovskaia, Elena; Cleverley, Robert M; Gierasch, Lila M; Ottensmeyer, F Peter; Andrews, David W
2006-12-01
Structural studies on various domains of the ribonucleoprotein signal recognition particle (SRP) have not converged on a single complete structure of bacterial SRP consistent with the biochemistry of the particle. We obtained a three-dimensional structure for Escherichia coli SRP by cryoscanning transmission electron microscopy and mapped the internal RNA by electron spectroscopic imaging. Crystallographic data were fit into the SRP reconstruction, and although the resulting model differed from previous models, they could be rationalized by movement through an interdomain linker of Ffh, the protein component of SRP. Fluorescence resonance energy transfer experiments determined interdomain distances that were consistent with our model of SRP. Docking our model onto the bacterial ribosome suggests a mechanism for signal recognition involving interdomain movement of Ffh into and out of the nascent chain exit site and suggests how SRP could interact and/or compete with the ribosome-bound chaperone, trigger factor, for a nascent chain during translation.
The Selective Mutism Questionnaire: Measurement Structure and Validity
Letamendi, Andrea M.; Chavira, Denise A.; Hitchcock, Carla A.; Roesch, Scott C.; Shipon-Blum, Elisa; Stein, Murray B.; Roesch, Scott C.
2010-01-01
Objective To evaluate the factor structure, reliability, and validity of the 17-item Selective Mutism Questionnaire. Method Diagnostic interviews were administered via telephone to 102 parents of children identified with selective mutism (SM) and 43 parents of children without SM from varying U.S. geographic regions. Children were between the ages of 3 and 11 inclusive and comprised 58% girls and 42% boys. SM diagnoses were determined using the Anxiety Disorders Interview Schedule for Children - Parent Version (ADIS-C/P); SM severity was assessed using the 17-item Selective Mutism Questionnaire (SMQ); and behavioral and affective symptoms were assessed using the Child Behavior Checklist (CBCL). An exploratory factor analysis (EFA) was conducted to investigate the dimensionality of the SMQ and a modified parallel analysis procedure was used to confirm EFA results. Internal consistency, construct validity, and incremental validity were also examined. Results The EFA yielded a 13-item solution consisting of three factors: a) Social Situations Outside of School, b) School Situations, and c) Home and Family Situations. Internal consistency of SMQ factors and total scale ranged from moderate to high. Convergent and incremental validity were also well supported. Conclusions Measure structure findings are consistent with the 3-factor solution found in a previous psychometric evaluation of the SMQ. Results also suggest that the SMQ provides useful and unique information in the prediction of SM phenomenon beyond other child anxiety measures. PMID:18698268
Swami, Viren; Vintila, Mona; Tudorel, Otilia; Goian, Cosmin; Barron, David
2018-06-01
We examined the psychometric properties of a Romanian translation of the 15-item Drive for Muscularity Scale (DMS). Male university students from Romania (N = 343) completed the DMS, as well as measures of self-esteem, body appreciation, and muscle discrepancy. Exploratory factor analysis indicated that DMS scores reduced to two factors that related to muscularity-oriented attitudes and behaviours, with both first-order factors loading onto a higher-order factor. However, confirmatory factor analysis indicated that a model with two first-order factors and a higher-order factor had poor fit. A two-factor model without a higher-order construct achieved acceptable but mediocre fit. Scores on the two-factor DMS model had adequate internal consistency and demonstrated acceptable convergent validity (significant correlations with self-esteem, body appreciation, and muscle discrepancy). These results provide support for a two-factor model of DMS scores in a Romanian-speaking sample and extends the availability of the DMS to a rarely-examined linguistic group. Copyright © 2018 Elsevier Ltd. All rights reserved.
Schematic memory components converge within angular gyrus during retrieval
Wagner, Isabella C; van Buuren, Mariët; Kroes, Marijn CW; Gutteling, Tjerk P; van der Linden, Marieke; Morris, Richard G; Fernández, Guillén
2015-01-01
Mental schemas form associative knowledge structures that can promote the encoding and consolidation of new and related information. Schemas are facilitated by a distributed system that stores components separately, presumably in the form of inter-connected neocortical representations. During retrieval, these components need to be recombined into one representation, but where exactly such recombination takes place is unclear. Thus, we asked where different schema components are neuronally represented and converge during retrieval. Subjects acquired and retrieved two well-controlled, rule-based schema structures during fMRI on consecutive days. Schema retrieval was associated with midline, medial-temporal, and parietal processing. We identified the multi-voxel representations of different schema components, which converged within the angular gyrus during retrieval. Critically, convergence only happened after 24-hour-consolidation and during a transfer test where schema material was applied to novel but related trials. Therefore, the angular gyrus appears to recombine consolidated schema components into one memory representation. DOI: http://dx.doi.org/10.7554/eLife.09668.001 PMID:26575291
The evolution of forearc structures along an oblique convergent margin, central Aleutian Arc
Ryan, H.F.; Scholl, D. W.
1989-01-01
Multichannel seismic reflection data were used to determine the evolutionary history of the forearc region of the central Aleutian Ridge. Since at least late Miocene time this sector of the ridge has been obliquely underthrust 30?? west of orthogonal convergence by the northwestward converging Pacific plate at a rate of 80-90 km/m.y. Our data indicate that prior to late Eocene time the forearc region was composed of rocks of the arc massif thinly mantled by slope deposits. Beginning in latest Miocene or earliest Pliocene time, a zone of outer-arc structural highs and a forearc basin began to form. Initial structures of the zone of outer-arc highs formed as the thickening wedge underran, compressively deformed, and uplifted the seaward edge of the arc massive above a landward dipping backstop thrust. Forearc basin strata ponded arcward of the elevating zone of outer-arc highs. However, most younger structures of the zone of outer-arc highs cannot be ascribed simply to the orthogonal effects of an underrunning wedge. Oblique convergence created a major right-lateral shear zone (the Hawley Ridge shear zone) that longitudinally disrupted the zone of outer-arc highs, truncating the seaward flank of the forearc basin and shearing the southern limb of Hawley Ridge, an exceptionally large antiformal outer-arc high structure. Uplift of Hawley Ridge may be related to the thickening of the arc massif by westward directed basement duplexes. Great structural complexity, including the close juxtaposition of coeval structures recording compression, extension, differential vertical movements, and strike-slip displacement, should be expected, even within areas of generally kindred tectonostratigraphic terranes. -from Authors
On a variational approach to some parameter estimation problems
NASA Technical Reports Server (NTRS)
Banks, H. T.
1985-01-01
Examples (1-D seismic, large flexible structures, bioturbation, nonlinear population dispersal) in which a variation setting can provide a convenient framework for convergence and stability arguments in parameter estimation problems are considered. Some of these examples are 1-D seismic, large flexible structures, bioturbation, and nonlinear population dispersal. Arguments for convergence and stability via a variational approach of least squares formulations of parameter estimation problems for partial differential equations is one aspect of the problem considered.
Mörtberg, Ewa; Reuterskiöld, Lena; Tillfors, Maria; Furmark, Tomas; Öst, Lars-Göran
2017-06-01
Culturally validated rating scales for social anxiety disorder (SAD) are of significant importance when screening for the disorder, as well as for evaluating treatment efficacy. This study examined construct validity and additional psychometric properties of two commonly used scales, the Social Phobia Scale and the Social Interaction Anxiety Scale, in a clinical SAD population (n = 180) and in a normal population (n = 614) in Sweden. Confirmatory factor analyses of previously reported factor solutions were tested but did not reveal acceptable fit. Exploratory factor analyses (EFA) of the joint structure of the scales in the total population yielded a two-factor model (performance anxiety and social interaction anxiety), whereas EFA in the clinical sample revealed a three-factor solution, a social interaction anxiety factor and two performance anxiety factors. The SPS and SIAS showed good to excellent internal consistency, and discriminated well between patients with SAD and a normal population sample. Both scales showed good convergent validity with an established measure of SAD, whereas the discriminant validity of symptoms of social anxiety and depression could not be confirmed. The optimal cut-off score for SPS and SIAS were 18 and 22 points, respectively. It is concluded that the factor structure and the additional psychometric properties of SPS and SIAS support the use of the scales for assessment in a Swedish population.
Mahoney, Alison E J; Hobbs, Megan J; Newby, Jill M; Williams, Alishia D; Sunderland, Matthew; Andrews, Gavin
2016-10-01
Understanding behavioral avoidance associated with generalized anxiety disorder (GAD) has implications for the classification, theoretical conceptualization, and clinical management of the disorder. This study describes the development and preliminary psychometric evaluation of a self-report measure of avoidant behaviors associated with GAD: the Worry Behaviors Inventory (WBI). The WBI was administered to treatment-seeking patients (N=1201). Convergent validity was assessed by correlating the WBI with measures of GAD symptom severity. Divergent validity was assessed by correlating the WBI with measures of general disability and measures of depression, social anxiety and panic disorder symptom severity. Exploratory and confirmatory factor analyses supported a two-factor structure (Safety Behaviors and Avoidance). Internal reliability was acceptable for the 10-item WBI scale (α=.86), Safety Behaviors (α=.85) and Avoidance subscales (α=.75). Evidence of convergent, divergent, and discriminant validity is reported. WBI subscales demonstrated differential associations with measures of symptom severity. The Safety Behaviors subscale was more strongly associated with GAD symptoms than symptoms of other disorders, whereas the Avoidance subscale was as strongly correlated with GAD severity as it was with depression, social anxiety and panic disorder severity. Structured diagnostic interviews were not conducted therefor validity analyses are limited to probable diagnoses based on self-report. The cross-sectional design precluded examination of the WBI's temporal stability and treatment sensitivity. Preliminary evidence supports the use of the WBI in research and clinical settings and may assist clinicians to identify behaviors that are theorized to maintain GAD and that can be targeted during psychological treatment. Copyright © 2016 Elsevier B.V. All rights reserved.
[Psychometric properties of the Eating Disorder Inventory (EDI-2) in adolescents].
Salbach-Andrae, Harriet; Schneider, Nora; Bürger, Arne; Pfeiffer, Ernst; Lehmkuhl, Ulrike; Holzhausen, Martin
2010-05-01
The present study examines the psychometric properties of the German version of the Eating Disorder Inventory EDI-2 (1997) in 371 adolescents aged 13 to 18 years. Internal consistency, convergent and divergent validity were examined and a confirmatory factor analysis was conducted. Internal consistency was high for the group of patients and satisfactory for both control groups. Associations with other clinical instruments point in the expected direction and support the external validity of the EDI-2. The EDI-2 differentiated very well between the group of eating disorder patients (n=71) and the female (n=150) and male control groups (n=150). A discriminant analysis demonstrated that 86.0% of the cases were correctly classified, and a confirmatory factor analysis largely supported the six-factor structure generated by the German version of the EDI-2 (Thiel et al., 1997).
Wilson, Keithia L; Charker, Jill; Lizzio, Alf; Halford, Kim; Kimlin, Siobhan
2005-09-01
It is widely believed that satisfying couple relationships require work by the partners. The authors equated the concept of work to relationship self-regulation and developed a scale to assess this construct. A factor analysis of the scale in a sample of 187 newlywed couples showed it comprised 2 factors of relationship strategies and effort. The factor structure was replicated in an independent sample of 97 newlywed couples. In both samples the scale had good internal consistency and high convergent validity between self- and partner-report forms. Self-regulation accounted for substantial variance in relationship satisfaction in both newlywed samples and in a 3rd sample of 61 long-married couples. The self-regulation and satisfaction association was independent of mood or self-report common method variance. (c) 2005 APA, all rights reserved
Simultaneous Tensor Decomposition and Completion Using Factor Priors.
Chen, Yi-Lei; Hsu, Chiou-Ting Candy; Liao, Hong-Yuan Mark
2013-08-27
Tensor completion, which is a high-order extension of matrix completion, has generated a great deal of research interest in recent years. Given a tensor with incomplete entries, existing methods use either factorization or completion schemes to recover the missing parts. However, as the number of missing entries increases, factorization schemes may overfit the model because of incorrectly predefined ranks, while completion schemes may fail to interpret the model factors. In this paper, we introduce a novel concept: complete the missing entries and simultaneously capture the underlying model structure. To this end, we propose a method called Simultaneous Tensor Decomposition and Completion (STDC) that combines a rank minimization technique with Tucker model decomposition. Moreover, as the model structure is implicitly included in the Tucker model, we use factor priors, which are usually known a priori in real-world tensor objects, to characterize the underlying joint-manifold drawn from the model factors. We conducted experiments to empirically verify the convergence of our algorithm on synthetic data, and evaluate its effectiveness on various kinds of real-world data. The results demonstrate the efficacy of the proposed method and its potential usage in tensor-based applications. It also outperforms state-of-the-art methods on multilinear model analysis and visual data completion tasks.
Watson, Shaun; Gomez, Rapson; Gullone, Eleonora
2017-06-01
This study examined various psychometric properties of the items comprising the shame and guilt scales of the Test of Self-Conscious Affect-Adolescent. A total of 563 adolescents (321 females and 242 males) completed these scales, and also measures of depression and empathy. Confirmatory factor analysis provided support for an oblique two-factor model, with the originally proposed shame and guilt items comprising shame and guilt factors, respectively. Also, shame correlated with depression positively and had no relation with empathy. Guilt correlated with depression negatively and with empathy positively. Thus, there was support for the convergent and discriminant validity of the shame and guilt factors. Multiple-group confirmatory factor analysis comparing females and males, based on the chi-square difference test, supported full metric invariance, the intercept invariance of 26 of the 30 shame and guilt items, and higher latent mean scores among females for both shame and guilt. Comparisons based on the difference in root mean squared error of approximation values supported full measurement invariance and no gender difference for latent mean scores. The psychometric and practical implications of the findings are discussed.
Lee, Soo Cheng; Moy, Foong Ming; Hairi, Noran Naqiah
2017-01-01
The multidimensional scale of perceived social support (MSPSS) was developed to measure perceived social support. It has been translated and culturally adapted among natives literate in the Malay language. However, its psychometric properties for teachers who are majority females and married have not been assessed. This was a cross-sectional study conducted among the public secondary school teachers in the central region of Peninsular Malaysia from May to July 2013. A total of 150 and 203 teachers were recruited to perform exploratory factor analysis and confirmatory factor analysis (CFA), respectively. Reliability testing was evaluated on 141 teachers via internal consistency and two-week interval test-retest. The 12-item three-factor structure of MSPSS-M was revised to 8-item two-factor structure. The revised MSPSS-M demonstrated excellent fit in CFA with adequate divergent and convergent validity and good factor loadings (0.80-0.90). The revised MSPSS-M also displayed good internal consistency with Cronbach's alpha of 0.91, 0.93 and 0.92 and good test-retest reliability with intraclass correlation of 0.89, 0.88 and 0.88 in the total scale, family and friends factors, respectively. The revised 8-item MSPSS-M is a reliable and valid tool for assessment of perceived social support among teachers.
Studer, Joseph; Baggio, Stéphanie; Mohler-Kuo, Meichun; Daeppen, Jean-Bernard; Gmel, Gerhard
2016-03-01
The Behavioural Inhibition System/Behavioural Activation System scales (BIS/BAS scales) constitute one of the most prominent questionnaires to assess individual differences in sensitivity to punishment and reward. However, some studies questioned its validity, especially that of the French and German translations. The aim of the present study was to re-evaluate the psychometric characteristics of the BIS/BAS scales in a large sample of French- and German-speaking young Swiss men (N = 5872). Results showed that factor structures previously found in the literature did not meet the standards of fit. Nine items had to be removed to achieve adequate fit statistics in confirmatory factor analysis, yielding a shortened version with four factors: one BIS factor comprising five items and three BAS factors, namely Reward Reactivity, Drive and Fun Seeking, each comprising two items. Convergent validity and group invariance analyses suggest that the shortened BIS/BAS scales constitute a valid and reliable instrument. Researchers interested in assessing individual differences in BIS and BAS reactivity in French- and German-speaking individuals should avoid using the BIS/BAS scales as originally specified. The shortened version may be a sound alternative at least in samples of young adults. Its shorter format may be particularly suited for surveys with constraints on questionnaire length.
Listening, Watching, and Reading: The Structure and Correlates of Entertainment Preferences
Rentfrow, Peter J.; Goldberg, Lewis R.; Zilca, Ran
2010-01-01
People spend considerable amounts of time and money listening to music, watching TV and movies, and reading books and magazines, yet almost no attention in psychology has been devoted to understanding individual differences in preferences for such entertainment. The present research was designed to examine the structure and correlates of entertainment genre preferences. Analyses of the genre preferences of over 3,000 individuals revealed a remarkably clear factor structure. Using multiple samples, methods, and geographic regions, data converged to reveal five entertainment-preference dimensions: Communal, Aesthetic, Dark, Thrilling, and Cerebral. Preferences for these entertainment dimensions were uniquely related to demographics and personality traits. Results also indicated that personality accounted for significant proportions of variance in entertainment preferences over and above demographics. The results provide a foundation for developing and testing hypotheses about the psychology of entertainment preferences. PMID:20649744
Bridging animal and human models of exercise-induced brain plasticity
Voss, Michelle W.; Vivar, Carmen; Kramer, Arthur F.; van Praag, Henriette
2015-01-01
Significant progress has been made in understanding the neurobiological mechanisms through which exercise protects and restores the brain. In this feature review, we integrate animal and human research, examining physical activity effects across multiple levels of description (neurons up to inter-regional pathways). We evaluate the influence of exercise on hippocampal structure and function, addressing common themes such as spatial memory and pattern separation, brain structure and plasticity, neurotrophic factors, and vasculature. Areas of research focused more within species, such as hippocampal neurogenesis in rodents, also provide crucial insight into the protective role of physical activity. Overall, converging evidence suggests exercise benefits brain function and cognition across the mammalian lifespan, which may translate into reduced risk for Alzheimer’s disease (AD) in humans. PMID:24029446
Tectono-magmatic relationships along an obliquely convergent plate boundary: Sumatra, Indonesia.
NASA Astrophysics Data System (ADS)
Acocella, Valerio; Bellier, Olivier
2017-04-01
The tectono-magmatic relationships along divergent and orthogonally convergent plate boundaries have been defined in several aspects. However, much less is known along obliquely convergent plate boundaries, where the strain partitioning promotes strike-slip structures along the volcanic arc. Here it is unclear if and, in case, how strike-slip structures may control arc volcanism, in terms of processes, distribution and size. To better define these features, we review the available tectonic, structural and volcanological data on Sumatra (Indonesia), which provides the ideal case study. The Sumatra volcanic arc consists of 48 major active volcanoes. Of these, 46% lie within 10 km from the dextral Great Sumatra Fault (GSF), which carries most of the strike-slip displacement on the overriding plate, whereas 27% of the volcanoes lie at >20 km from the GSF. Considering the volcanoes lying within 10 km from GSF, 76% show some possible structural relation to the GSF, whereas only 28% (7 volcanoes) show a clear structural relation to the GSF, being located in pull-apart or releasing bends between dextral segments. However, these localized areas of extension do not seem to promote the development of magmatic segments, similarly to orthogonally convergent plate boundaries. Many volcanoes lie to the west of the GSF, largely following the shallower portions of the slab, which reaches its average partial melting depth (130±30 km) more westward. There is a preferred volcano alignment and elongation along the N30-N40°E trend, almost parallel to the convergence vector; this trend coincides with the direction of the extensional structures found along the arc. Other volcanoes are elongated parallel to the GSF, possibly resulting from the co- and post-seismic across-arc extension, as observed during the 2004 mega-earthquake. Finally, there is no relationship between the slip rate along GSF and the erupted volumes along the arc: the highest productivity of Toba caldera may be explained by a slab tear. Overall, these data highlight a limited control of the geometry and kinematics of the GSF on the arc volcanism of Sumatra. This control is mostly confined to the: a) suitable depth for partial melting of the slab; b) structural configuration of the GSF, promoting localized extension. Otherwise, magma may rise far from the GSF, where the direction of the feeder dikes may be controlled by the inter-seismic extension (perpendicular to the convergence vector) or by the arc normal co- and post-seismic extension.
NASA Technical Reports Server (NTRS)
Chang, S. C.
1986-01-01
A two-step semidirect procedure is developed to accelerate the one-step procedure described in NASA TP-2529. For a set of constant coefficient model problems, the acceleration factor increases from 1 to 2 as the one-step procedure convergence rate decreases from + infinity to 0. It is also shown numerically that the two-step procedure can substantially accelerate the convergence of the numerical solution of many partial differential equations (PDE's) with variable coefficients.
Assessments of astronaut effectiveness
NASA Technical Reports Server (NTRS)
Rose, Robert M.; Helmreich, Robert L.; Fogg, Louis; Mcfadden, Terry J.
1993-01-01
This study examined the reliability and convergent validity of three methods of peer and supervisory ratings of the effectiveness of individual NASA astronauts and their relationships with flight assignments. These two techniques were found to be reliable and relatively convergent. Seniority and a peer-rated Performance and Competence factor proved to be most closely associated with flight assignments, while supervisor ratings and a peer-rated Group Living and Personality factor were found to be unrelated. Results have implications for the selection and training of astronauts.
2016-09-01
The period of investigation for the expanded case study centers on the Eisenhower administration, but also addresses factors that occurred immediately...Understanding how institutional path dependent factors converged in each of these cases may shed light on how to prevent such foreign policy missteps in the...converged in each of these cases may shed light on how to prevent such foreign policy missteps in the future. vi THIS PAGE INTENTIONALLY LEFT BLANK
Convergent and Divergent Validity of the Learning Transfer System Inventory
ERIC Educational Resources Information Center
Holton, Elwood F., III; Bates, Reid A.; Bookter, Annette I.; Yamkovenko, V. Bogdan
2007-01-01
The Learning Transfer System Inventory (LTSI) was developed to identify a select set of factors with the potential to substantially enhance or inhibit transfer of learning to the work environment. It has undergone a variety of validation studies, including construct, criterion, and crosscultural studies. However, the convergent and divergent…
Bottesi, Gioia; Ghisi, Marta; Altoè, Gianmarco; Conforti, Erica; Melli, Gabriele; Sica, Claudio
2015-07-01
The Depression Anxiety Stress Scales-21 (DASS-21) is the short version of a self-report measure that was originally developed to provide maximum differentiation between depressive and anxious symptoms. Despite encouraging evidence, the factor structure and other features of the DASS-21 are yet to be firmly established. A community sample of 417 participants and two clinical groups (32 depressive patients and 25 anxious patients) completed the Italian version of the DASS-21 along with several measures of psychopathology. Confirmatory factor analyses suggested that the DASS-21 is a measure of general distress plus three additional orthogonal dimensions (anxiety, depression, and stress). The internal consistency and temporal stability of the measure were good; each DASS-21 scale correlated more strongly with a measure of a similar construct, demonstrating good convergent and divergent validity. Lastly, the DASS-21 demonstrated good criterion-oriented validity. The validity of the Italian DASS-21 and its utility, both for community and clinical individuals, are supported. Copyright © 2015 Elsevier Inc. All rights reserved.
Alleva, Jessica M; Martijn, Carolien; Veldhuis, Jolanda; Tylka, Tracy L
2016-12-01
This paper describes a Dutch translation and validation of the Body Appreciation Scale-2 (BAS-2; Tylka & Wood-Barcalow, 2015a), an instrument for assessing key components of positive body image. Dutch-speaking female university students (N=310, M age =21.31, SD=3.04) completed the Dutch BAS-2. To assess its construct validity, participants also completed measures of appearance satisfaction, functionality satisfaction, self-objectification, self-esteem, and optimistic life orientation. Exploratory factor analysis revealed a one-dimensional factor structure of the Dutch BAS-2, substantiating the BAS-2 factor structure found in samples of U.S., Chinese, and Iranian university students and community adults. Dutch BAS-2 scores also demonstrated good internal consistency (α=.90), convergent validity, and incremental validity. In addition, lower body mass indices were associated with higher Dutch BAS-2 scores. The present findings support the cross-cultural equivalence of the BAS-2 and thus its promise in enabling research on positive body image in diverse cultural contexts. Copyright © 2016 Elsevier Ltd. All rights reserved.
An Evaluation of the Texas Functional Living Scale's Latent Structure and Subscales.
González, David Andrés; Soble, Jason R; Marceaux, Janice C; McCoy, Karin J M
2017-02-01
Performance-based functional assessment is a critical component of neuropsychological practice. The Texas Functional Living Scale (TFLS) has promise given its brevity, nationally representative norms, and co-norming with Wechsler scales. However, its subscale structure has not been evaluated. The purpose of this study was to evaluate the TFLS in a mixed clinical sample (n = 197). Reliability and convergent and discriminant validity coefficients were calculated with neurocognitive testing and collateral reports and factor analysis was performed. The Money and Calculation subscale had the best psychometric properties of the subscales. The evidence did not support solitary interpretation of the Time subscale. A three-factor latent structure emerged representing memory and semantic retrieval, performance and visual scanning, and financial calculation. This study added psychometric support for interpretation of the TFLS total score and some of its subscales. Study limitations included sample characteristics (e.g., gender ratio) and low power for collateral report analyses. Published by Oxford University Press 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Validation of the Rational and Experiential Multimodal Inventory in the Italian Context.
Monacis, Lucia; de Palo, Valeria; Di Nuovo, Santo; Sinatra, Maria
2016-08-01
The unfavorable relations of the Rational and Experiential Inventory Experiential scale with objective criterion measures and its limited content validity led Norris and Epstein to propose a more content-valid measure of the experiential thinking style, the Rational and Experiential Multimodal Inventory (REIm), in order to assess the several facets of a broader experiential system consisting of interrelated components. This study aimed to provide the Italian validation of the inventory by examining its psychometric features, its factor structure (Study 1, N = 545), and its convergent and discriminant validity (Study 2, N = 257). Study 1 supported the 2- and 4-factor solutions, and multi-group analyses confirmed the invariance measurement across age and gender for both models. Study 2 provided evidence for both the convergent validity by supporting the theoretical associations among Rational and Experiential Multimodal Inventory scores and similar and related measures, and the discriminant validity by showing associations between the two thinking styles and a different but conceptually related construct, i.e., identity formation. No associations between Rational and Experiential Multimodal Inventory scores and social desirability were found. The Italian version of the Rational and Experiential Multimodal Inventory showed satisfactory psychometric properties, thus confirming its validity. © The Author(s) 2016.
Lupano Perugini, María Laura; de la Iglesia, Guadalupe; Castro Solano, Alejandro; Keyes, Corey Lee M.
2017-01-01
The present research aimed at studying the psychometric properties of the Mental Health Continuum–Short Form (MHC–SF; Keyes, 2005) in a sample of 1,300 Argentinean adults (50% males; 50% females). Their mean age was 40.28 years old (SD = 13.59). The MHC–SF is a 14 item test that assesses three components (i.e., emotional, social, and psychological) of well-being. Convergent and divergent evidence of construct validity was assessed by conducting confirmatory factor analysis, cross-validation, factorial invariance, and correlations with external criteria. Internal consistency was studied using Cronbach’s alphas. Results indicated an adequate fit of a three-dimensional model. This structure was also confirmed, and was invariant throughout sex and age. The emotional well-being scores converged with life satisfaction and positive affect measures; the psychological well-being scale had a positive association with the presence of meaning in life; and the social well-being scores showed a positive and strong correlation with an external measure of well-being. Also, all scores were negatively associated with negative affect, search of meaning in life, and presence of depression symptoms. Internal consistency was .89 for the MHC–SF. Furthermore, the findings supported the two - continua model of mental health. PMID:28344677
Bandeira, Marina; Felicio, Cynthia Mara; Cesari, Luciana
2010-09-01
This study aimed to validate the Perception of Change Scale - Family Version, which evaluates the perception of family caregivers in regard to the treatment outcomes of psychiatric patients in mental health services. Family caregivers (N = 300) of psychiatric patients attending mental health services completed the Perception of Change Scale - Family Version. The scale has 19 items rated in a three-point Likert scale that evaluate changes perceived in the patient's life as a result of treatment. The factorial analysis revealed a four-factor structure, with the following dimensions: 1) occupation, 2) psychological factors, 3) relationships, and 4) physical health. In the internal consistency analysis, Cronbach's alpha coefficient was 0.85. The test-retest temporal stability analysis yielded a significant intraclass correlation coefficient (r = 0.96; p < 0.005). The convergent validity analysis revealed a positive significant correlation with another scale evaluating a distinct but theoretically related construct of family satisfaction with services (r = 0.41; p < 0.05). The Perception of Change Scale - Family Version has adequate reliability and construct and convergent validity. It can be used to evaluate treatment outcome in mental health services from the perspective of family caregivers, indicating targets to improve treatment.
NASA Astrophysics Data System (ADS)
Szafarczyk, Anna; Gawałkiewicz, Rafał
2018-03-01
There are many ways of the geometry measurement of slim objects, with the application of geodetic and photogrammetric methods. A modern solution in the diagnostics of slim objects is the application of laser scanning, with the use of a scanner of a scanning total station. The point cloud, obtained from the surface of the scanned object gives the possibility of generating not only information on structural surface deformations, but also facilitates obtaining the data on the geometry of the axis of the building, as a basic indicator of the characteristics of its deformation. The cause of the change in the geometry of slim objects is the impact of many external and internal factors. These objects are located in the areas of working or closed underground mines. They can be impacted by the ground and they can face the results of the convergence of cavities. A specific structure of the salt rock mass causes subsequent convergence of the post-exploitation cavities, which has the influence on the behaviour of the terrain surface and the related objects. The authors analysed the impact of the changes in the rock mass and the surface on the changes of the industrial chimney in the Bochnia Salt Mine.
Petri, Andrea; May, Morgan; Haiman, Zoltán
2016-09-30
Weak gravitational lensing is becoming a mature technique for constraining cosmological parameters, and future surveys will be able to constrain the dark energy equation of state w. When analyzing galaxy surveys, redshift information has proven to be a valuable addition to angular shear correlations. We forecast parameter constraints on the triplet (Ω m,w,σ 8) for a LSST-like photometric galaxy survey, using tomography of the shear-shear power spectrum, convergence peak counts and higher convergence moments. Here we find that redshift tomography with the power spectrum reduces the area of the 1σ confidence interval in (Ω m,w) space by a factor ofmore » 8 with respect to the case of the single highest redshift bin. We also find that adding non-Gaussian information from the peak counts and higher-order moments of the convergence field and its spatial derivatives further reduces the constrained area in (Ω m,w) by factors of 3 and 4, respectively. When we add cosmic microwave background parameter priors from Planck to our analysis, tomography improves power spectrum constraints by a factor of 3. Adding moments yields an improvement by an additional factor of 2, and adding both moments and peaks improves by almost a factor of 3 over power spectrum tomography alone. We evaluate the effect of uncorrected systematic photometric redshift errors on the parameter constraints. In conclusion, we find that different statistics lead to different bias directions in parameter space, suggesting the possibility of eliminating this bias via self-calibration.« less
Capitalism, Identity Politics, and Queerness Converge: LGBT Employee Resource Groups
ERIC Educational Resources Information Center
Githens, Rod P.
2009-01-01
Lesbian, gay, bisexual, and transgender (LGBT) employee resource groups have brought about substantial organizational change within corporations. Capitalist structures have enabled these changes to occur more quickly in the private sector than within the public sector. In this article, I explore how capitalism has converged with two approaches of…
Usage-Based Language: Investigating the Latent Structures That Underpin Acquisition
ERIC Educational Resources Information Center
Ellis, Nick C.; O'Donnell, Matthew Brook; Romer, Ute
2013-01-01
Each of us as language learners had different language experiences, yet somehow we have converged upon broadly the same language system. From diverse, often noisy samples, we have attained similar linguistic competence. How so? What mechanisms channel language acquisition? Could our linguistic commonalities possibly have converged from our shared…
Convergence acceleration of molecular dynamics methods for shocked materials using velocity scaling
NASA Astrophysics Data System (ADS)
Taylor, DeCarlos E.
2017-03-01
In this work, a convergence acceleration method applicable to extended system molecular dynamics techniques for shock simulations of materials is presented. The method uses velocity scaling to reduce the instantaneous value of the Rankine-Hugoniot conservation of energy constraint used in extended system molecular dynamics methods to more rapidly drive the system towards a converged Hugoniot state. When used in conjunction with the constant stress Hugoniostat method, the velocity scaled trajectories show faster convergence to the final Hugoniot state with little difference observed in the converged Hugoniot energy, pressure, volume and temperature. A derivation of the scale factor is presented and the performance of the technique is demonstrated using the boron carbide armour ceramic as a test material. It is shown that simulation of boron carbide Hugoniot states, from 5 to 20 GPa, using both a classical Tersoff potential and an ab initio density functional, are more rapidly convergent when the velocity scaling algorithm is applied. The accelerated convergence afforded by the current algorithm enables more rapid determination of Hugoniot states thus reducing the computational demand of such studies when using expensive ab initio or classical potentials.
Trophic divergence despite morphological convergence in a continental radiation of snakes
Grundler, Michael C.; Rabosky, Daniel L.
2014-01-01
Ecological and phenotypic convergence is a potential outcome of adaptive radiation in response to ecological opportunity. However, a number of factors may limit convergence during evolutionary radiations, including interregional differences in biogeographic history and clade-specific constraints on form and function. Here, we demonstrate that a single clade of terrestrial snakes from Australia—the oxyuranine elapids—exhibits widespread morphological convergence with a phylogenetically diverse and distantly related assemblage of snakes from North America. Australian elapids have evolved nearly the full spectrum of phenotypic modalities that occurs among North American snakes. Much of the convergence appears to involve the recurrent evolution of stereotyped morphologies associated with foraging mode, locomotion and habitat use. By contrast, analysis of snake diets indicates striking divergence in feeding ecology between these faunas, partially reflecting regional differences in ecological allometry between Australia and North America. Widespread phenotypic convergence with the North American snake fauna coupled with divergence in feeding ecology are clear examples of how independent continental radiations may converge along some ecological axes yet differ profoundly along others. PMID:24920479
Trophic divergence despite morphological convergence in a continental radiation of snakes.
Grundler, Michael C; Rabosky, Daniel L
2014-07-22
Ecological and phenotypic convergence is a potential outcome of adaptive radiation in response to ecological opportunity. However, a number of factors may limit convergence during evolutionary radiations, including interregional differences in biogeographic history and clade-specific constraints on form and function. Here, we demonstrate that a single clade of terrestrial snakes from Australia--the oxyuranine elapids--exhibits widespread morphological convergence with a phylogenetically diverse and distantly related assemblage of snakes from North America. Australian elapids have evolved nearly the full spectrum of phenotypic modalities that occurs among North American snakes. Much of the convergence appears to involve the recurrent evolution of stereotyped morphologies associated with foraging mode, locomotion and habitat use. By contrast, analysis of snake diets indicates striking divergence in feeding ecology between these faunas, partially reflecting regional differences in ecological allometry between Australia and North America. Widespread phenotypic convergence with the North American snake fauna coupled with divergence in feeding ecology are clear examples of how independent continental radiations may converge along some ecological axes yet differ profoundly along others. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Lee, Siau Pheng; Ong, Clarissa; Sagayadevan, Vathsala; Ong, Rebecca; Abdin, Edimansyah; Lim, Susan; Vaingankar, Janhavi; Picco, Louisa; Verma, Swapna; Chong, Siow Ann; Subramaniam, Mythily
2016-10-26
The growing interest in problematic hoarding as an independent clinical condition has led to the development of the Saving Inventory-Revised (SI-R) to assess hoarding phenomenology. The SI-R is one of the most widely used instruments to measure hoarding symptoms; however, it lacks validation in non-Western samples. The current study examined the construct, convergent, and discriminant validity of the SI-R among 500 outpatients at a psychiatric hospital in Singapore. The three-factor structure solution of the SI-R was fitted in a confirmatory factor analysis. The final model achieved mediocre fit (χ2 = 1026.02, df = 186; RMSEA = 0.095, SRMR = 0.06; CFI = 0.86; NNFI = 0.85). Two reverse-coded items (items 2 and 4) were removed due to insufficient factor loadings, resulting in the modified 21-item SI-R (SIR-21). Our findings indicate the need to further examine the construct validity of the SI-R, particularly in non-Western samples. Nonetheless, correlations with other hoarding-related constructs, such as anxiety (Beck Anxiety Inventory) and depression (Beck Depression Inventory-II), supported the convergent and discriminant validity of the SIR-21 in our sample. Findings in our current majority Chinese sample were consistent with previous observations from other Chinese samples. Implications were discussed from a cross-cultural perspective, such as cultural emphasis on saving for future use and overlap between the concepts of discarding and acquiring in Chinese samples. Future studies should also examine differences among other ethnic groups (e.g., Malay, Indian).
Lin, Xiao-Ling; Lu, Da-Li; Gottschling, Juliana; Segal, Daniel L; Tang, Si-Yuan
2017-03-01
The Geriatric Anxiety Scale (GAS) was developed as an international screening instrument for anxiety in older adults. The aims of the present study were to translate the GAS into Chinese and to subsequently evaluate the preliminary psychometric properties of the Chinese version of the GAS (GAS-C) among community-dwelling Chinese older adults. The translation of the GAS into Chinese was developed through a translation and back translation process. A sample of 206 community-dwelling older adults (51.9 % men, Mean age = 70.70 years, SD = 8.15 years) completed the GAS-C, the Beck Anxiety Inventory (BAI), the Geriatric Depression Scale (GDS) and the Pittsburgh Sleep Quality Index (PSQI). A confirmatory factor analysis was conducted to examine the factor structure of the GAS-C. Internal consistency and convergent validity were used to evaluate the psychometric properties of the translated measure. The factor analyses were in support of a unidimensional factor model of the GAS-C in this Chinese sample, and the item-total correlations for all 25 items ranged from 0.40 to 0.83. The internal consistency for the GAS-C total score was excellent (α = 0.92). The GAS-C total score were significantly and strongly correlated with the BAI (r = 0.86), the GDS (r = 0.78) and the PSQI (r = 0.63), which indicated good convergent validity of the GAS-C. The GAS-C appears to be a reliable and valid screening instrument to assess anxiety symptoms among community-dwelling older adults in mainland China.
Kim, Sunny S; Avula, Rasmi; Ved, Rajani; Kohli, Neha; Singh, Kavita; van den Bold, Mara; Kadiyala, Suneetha; Menon, Purnima
2017-02-02
Convergence of sectoral programs is important for scaling up essential maternal and child health and nutrition interventions. In India, these interventions are implemented by two government programs - Integrated Child Development Services (ICDS) and National Rural Health Mission (NRHM). These programs are designed to work together, but there is limited understanding of the nature and extent of coordination in place and needed at the various administrative levels. Our study examined how intersectoral convergence in nutrition programming is operationalized between ICDS and NRHM from the state to village levels in Odisha, and the factors influencing convergence in policy implementation and service delivery. Semi-structured interviews were conducted with state-level stakeholders (n = 12), district (n = 19) and block officials (n = 66), and frontline workers (FLWs, n = 48). Systematic coding and content analysis of transcripts were undertaken to elucidate themes and patterns related to the degree and mechanisms of convergence, types of actions/services, and facilitators and barriers. Close collaboration at state level was observed in developing guidelines, planning, and reviewing programs, facilitated by a shared motivation and recognized leadership for coordination. However, the health department was perceived to drive the agenda, and different priorities and little data sharing presented challenges. At the district level, there were joint planning and review meetings, trainings, and data sharing, but poor participation in the intersectoral meetings and limited supervision. While the block level is the hub for planning and supervision, cooperation is limited by the lack of guidelines for coordination, heavy workload, inadequate resources, and poor communication. Strong collaboration among FLWs was facilitated by close interpersonal communication and mutual understanding of roles and responsibilities. Congruent or shared priorities and regularity of actions between sectors across all levels will likely improve the quality of coordination, and clear roles and leadership and accountability are imperative. As convergence is a means to achieving effective coverage and delivery of services for improved maternal and child health and nutrition, focus should be on delivering all the essential services to the mother-child dyads through mechanisms that facilitate a continuum of care approach, rather than sectorally-driven, service-specific delivery processes.
Genome-Wide Convergence during Evolution of Mangroves from Woody Plants.
Xu, Shaohua; He, Ziwen; Guo, Zixiao; Zhang, Zhang; Wyckoff, Gerald J; Greenberg, Anthony; Wu, Chung-I; Shi, Suhua
2017-04-01
When living organisms independently invade a new environment, the evolution of similar phenotypic traits is often observed. An interesting but contentious issue is whether the underlying molecular biology also converges in the new habitat. Independent invasions of tropical intertidal zones by woody plants, collectively referred to as mangrove trees, represent some dramatic examples. The high salinity, hypoxia, and other stressors in the new habitat might have affected both genomic features and protein structures. Here, we developed a new method for detecting convergence at conservative Sites (CCS) and applied it to the genomic sequences of mangroves. In simulations, the CCS method drastically reduces random convergence at rapidly evolving sites as well as falsely inferred convergence caused by the misinferences of the ancestral character. In mangrove genomes, we estimated ∼400 genes that have experienced convergence over the background level of convergence in the nonmangrove relatives. The convergent genes are enriched in pathways related to stress response and embryo development, which could be important for mangroves' adaptation to the new habitat. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Triclinic lysozyme at 0.65 angstrom resolution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, J.; Dauter, M.; Alkire, R.
The crystal structure of triclinic hen egg-white lysozyme (HEWL) has been refined against diffraction data extending to 0.65 {angstrom} resolution measured at 100 K using synchrotron radiation. Refinement with anisotropic displacement parameters and with the removal of stereochemical restraints for the well ordered parts of the structure converged with a conventional R factor of 8.39% and an R{sub free} of 9.52%. The use of full-matrix refinement provided an estimate of the variances in the derived parameters. In addition to the 129-residue protein, a total of 170 water molecules, nine nitrate ions, one acetate ion and three ethylene glycol molecules weremore » located in the electron-density map. Eight sections of the main chain and many side chains were modeled with alternate conformations. The occupancies of the water sites were refined and this step is meaningful when assessed by use of the free R factor. A detailed description and comparison of the structure are made with reference to the previously reported triclinic HEWL structures refined at 0.925 {angstrom} (at the low temperature of 120 K) and at 0.95 {angstrom} resolution (at room temperature).« less
The psychometric properties of the 5-item gratitude questionnaire in Chinese adolescents.
Zeng, Y; Ling, Y; Huebner, E S; He, Y; Lei, X
2017-05-01
WHAT IS KNOWN ON THE SUBJECT?: The GQ-6 is one of the most widely used self-report questionnaires to evaluate the level of gratitude among adults. The GQ-5 appears suitable for adolescents. WHAT THIS PAPER ADDS TO EXISTING KNOWLEDGE?: We developed a Chinese version of the GQ-5 and examined evidence for its reliability and validity. Results demonstrated adequate reliability and validity, indicating that it is appropriate for the assessment of gratitude in Chinese adolescents. In addition, Chinese early adolescent females reported higher gratitude than adolescent males. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Screening adolescents who have lower levels of gratitude through the GQ-5 could help identify students who may benefit from empirically validated interventions to promote higher levels of gratitude in an effort to promote positive psychosocial and academic outcomes. Background This study was conducted to evaluate the psychometric properties of the Chinese version of the 5-item Gratitude Questionnaire (GQ-5). Method The sample consisted of 2093 middle school students (46.8% males) in mainland China. Confirmatory factor analysis and multigroup confirmatory factor analysis were performed to examine the factor structure and the measurement equivalence across gender. The convergent validity, Cronbach's α and mean interitem correlations of the GQ-5 were also evaluated. Results The results provided evidence of internal consistency reliability through a Cronbach's α of 0.812 and a mean interitem correlation of 0.463 for the total sample. The results also supported a one-dimensional factor structure. In addition, convergent validity was assessed by statistically significant positive correlations between the GQ-5 and the two subscales of the Children's Hope Scale (CHS) and the Brief Multidimensional Students' Life Satisfaction Scale (BMSLSS) total score. Finally, multigroup confirmatory factor analysis also demonstrated measurement equivalence across gender. Subsequent analyses of latent mean revealed gender differences in early adolescent male and female students. Conclusions The Chinese version of the GQ-5 appears to be a reliable and valid measure of gratitude among Chinese early adolescents. Early adolescent female students reported higher gratitude than early adolescent male students. © 2017 John Wiley & Sons Ltd.
How hot? Systematic convergence of the replica exchange method using multiple reservoirs.
Ruscio, Jory Z; Fawzi, Nicolas L; Head-Gordon, Teresa
2010-02-01
We have devised a systematic approach to converge a replica exchange molecular dynamics simulation by dividing the full temperature range into a series of higher temperature reservoirs and a finite number of lower temperature subreplicas. A defined highest temperature reservoir of equilibrium conformations is used to help converge a lower but still hot temperature subreplica, which in turn serves as the high-temperature reservoir for the next set of lower temperature subreplicas. The process is continued until an optimal temperature reservoir is reached to converge the simulation at the target temperature. This gradual convergence of subreplicas allows for better and faster convergence at the temperature of interest and all intermediate temperatures for thermodynamic analysis, as well as optimizing the use of multiple processors. We illustrate the overall effectiveness of our multiple reservoir replica exchange strategy by comparing sampling and computational efficiency with respect to replica exchange, as well as comparing methods when converging the structural ensemble of the disordered Abeta(21-30) peptide simulated with explicit water by comparing calculated Rotating Overhauser Effect Spectroscopy intensities to experimentally measured values. Copyright 2009 Wiley Periodicals, Inc.
The application of contraction theory to an iterative formulation of electromagnetic scattering
NASA Technical Reports Server (NTRS)
Brand, J. C.; Kauffman, J. F.
1985-01-01
Contraction theory is applied to an iterative formulation of electromagnetic scattering from periodic structures and a computational method for insuring convergence is developed. A short history of spectral (or k-space) formulation is presented with an emphasis on application to periodic surfaces. To insure a convergent solution of the iterative equation, a process called the contraction corrector method is developed. Convergence properties of previously presented iterative solutions to one-dimensional problems are examined utilizing contraction theory and the general conditions for achieving a convergent solution are explored. The contraction corrector method is then applied to several scattering problems including an infinite grating of thin wires with the solution data compared to previous works.
The role of boundary layer momentum advection in the mean location of the ITCZ
NASA Astrophysics Data System (ADS)
Dixit, Vishal; Srinivasan, J.
2017-08-01
The inter-tropical convergence zones (ITCZ) form closer to the equator during equinoxes while they form well away from the equator during the boreal summer. A simple three-way balance between the pressure gradients, Coriolis force and effective Rayleigh friction has been classically used to diagnose the location of maximum boundary layer convergence in the near equatorial ITCZ. If such a balance can capture the dynamics of off-equatorial convergence was not known. We used idealized aqua planet simulations with fixed, zonally symmetric sea surface temperature boundary conditions to simulate the near equatorial and off-equatorial ITCZ. As opposed to the convergence of inter-hemispheric flows in the near equatorial convergence, the off-equatorial convergence forms due to the deceleration of cross-equatorial meridional flow. The detailed momentum budget of the off-equatorial convergence zone reveals that the simple balance is not sufficient to capture the relevant dynamics. The deceleration of the meridional flow is strongly modulated by the inertial effects due to the meridional advection of zonal momentum in addition to the terms in the simple balance. The simple balance predicts a spurious near equatorial convergence and a consistent off-equatorial convergence of the meridional flow. The spurious convergence disappears when inertial effects are included in the balance. As cross equatorial meridional flow decelerates to form convergence, the inertial effects cancel the pressure gradient effects near the equator while they add away from the equator. The contribution to the off-equatorial convergence induced by the pressure gradients is significantly larger than the contribution due to the inertial effects and hence pressure gradients appear to be the primary factor in anchoring the strength and location of the off-equatorial convergence.
Sharif Nia, Hamid; Pahlevan Sharif, Saeed; Koocher, Gerald P; Yaghoobzadeh, Ameneh; Haghdoost, Ali Akbar; Mar Win, Ma Thin; Soleimani, Mohammad Ali
2017-01-01
This study aimed to evaluate the validity and reliability of the Persian version of Death Anxiety Scale-Extended (DAS-E). A total of 507 patients with end-stage renal disease completed the DAS-E. The factor structure of the scale was evaluated using exploratory factor analysis with an oblique rotation and confirmatory factor analysis. The content and construct validity of the DAS-E were assessed. Average variance extracted, maximum shared squared variance, and average shared squared variance were estimated to assess discriminant and convergent validity. Reliability was assessed using Cronbach's alpha coefficient (α = .839 and .831), composite reliability (CR = .845 and .832), Theta (θ = .893 and .867), and McDonald Omega (Ω = .796 and .743). The analysis indicated a two-factor solution. Reliability and discriminant validity of the factors was established. Findings revealed that the present scale was a valid and reliable instrument that can be used in assessment of death anxiety in Iranian patients with end-stage renal disease.
Psychometric properties of the Drive for Muscularity Scale in Malay men.
Swami, Viren; Barron, David; Lau, Poh Li; Jaafar, Jas Laile
2016-06-01
The Drive for Muscularity Scale (DMS) is a widely used measure in studies of men's body image, but few studies have examined its psychometric properties outside English-speaking samples. Here, we assessed the factor structure of a Malay translation of the DMS. A community sample of 159 Malay men from Kuala Lumpur, Malaysia, completed the DMS, along with measures of self-esteem, body appreciation, and muscle discrepancy. Exploratory factor analysis led to the extraction of two factors, differentiating attitudes from behaviours, which mirrors the parent scale. Both factors also loaded on to a higher-order drive for muscularity factor. The subscales of the Malay DMS had adequate internal consistencies and good convergent validity, insofar as significant relationships were reported with self-esteem, body appreciation, muscle discrepancy, and body mass index. These results indicate that the Malay DMS has acceptable psychometric properties and can be used to assess body image concerns in Malay men. Copyright © 2016 Elsevier Ltd. All rights reserved.
Ovtchinnikov, Evgueni E.; Xanthis, Leonidas S.
2000-01-01
We present a methodology for the efficient numerical solution of eigenvalue problems of full three-dimensional elasticity for thin elastic structures, such as shells, plates and rods of arbitrary geometry, discretized by the finite element method. Such problems are solved by iterative methods, which, however, are known to suffer from slow convergence or even convergence failure, when the thickness is small. In this paper we show an effective way of resolving this difficulty by invoking a special preconditioning technique associated with the effective dimensional reduction algorithm (EDRA). As an example, we present an algorithm for computing the minimal eigenvalue of a thin elastic plate and we show both theoretically and numerically that it is robust with respect to both the thickness and discretization parameters, i.e. the convergence does not deteriorate with diminishing thickness or mesh refinement. This robustness is sine qua non for the efficient computation of large-scale eigenvalue problems for thin elastic structures. PMID:10655469
Fast sparse recovery and coherence factor weighting in optoacoustic tomography
NASA Astrophysics Data System (ADS)
He, Hailong; Prakash, Jaya; Buehler, Andreas; Ntziachristos, Vasilis
2017-03-01
Sparse recovery algorithms have shown great potential to reconstruct images with limited view datasets in optoacoustic tomography, with a disadvantage of being computational expensive. In this paper, we improve the fast convergent Split Augmented Lagrangian Shrinkage Algorithm (SALSA) method based on least square QR (LSQR) formulation for performing accelerated reconstructions. Further, coherence factor is calculated to weight the final reconstruction result, which can further reduce artifacts arising in limited-view scenarios and acoustically heterogeneous mediums. Several phantom and biological experiments indicate that the accelerated SALSA method with coherence factor (ASALSA-CF) can provide improved reconstructions and much faster convergence compared to existing sparse recovery methods.
Monacis, Lucia; Palo, Valeria de; Griffiths, Mark D; Sinatra, Maria
2016-12-01
Background and aims The inclusion of Internet Gaming Disorder (IGD) in Section III of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders has increased the interest of researchers in the development of new standardized psychometric tools for the assessment of such a disorder. To date, the nine-item Internet Gaming Disorder Scale - Short-Form (IGDS9-SF) has only been validated in English, Portuguese, and Slovenian languages. Therefore, the aim of this investigation was to examine the psychometric properties of the IGDS9-SF in an Italian-speaking sample. Methods A total of 757 participants were recruited to the present study. Confirmatory factor analysis and multi-group analyses were applied to assess the construct validity. Reliability analyses comprised the average variance extracted, the standard error of measurement, and the factor determinacy coefficient. Convergent and criterion validities were established through the associations with other related constructs. The receiver operating characteristic curve analysis was used to determine an empirical cut-off point. Results Findings confirmed the single-factor structure of the instrument, its measurement invariance at the configural level, and the convergent and criterion validities. Satisfactory levels of reliability and a cut-off point of 21 were obtained. Discussion and conclusions The present study provides validity evidence for the use of the Italian version of the IGDS9-SF and may foster research into gaming addiction in the Italian context.
Monacis, Lucia; de Palo, Valeria; Griffiths, Mark D.; Sinatra, Maria
2016-01-01
Background and aims The inclusion of Internet Gaming Disorder (IGD) in Section III of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders has increased the interest of researchers in the development of new standardized psychometric tools for the assessment of such a disorder. To date, the nine-item Internet Gaming Disorder Scale – Short-Form (IGDS9-SF) has only been validated in English, Portuguese, and Slovenian languages. Therefore, the aim of this investigation was to examine the psychometric properties of the IGDS9-SF in an Italian-speaking sample. Methods A total of 757 participants were recruited to the present study. Confirmatory factor analysis and multi-group analyses were applied to assess the construct validity. Reliability analyses comprised the average variance extracted, the standard error of measurement, and the factor determinacy coefficient. Convergent and criterion validities were established through the associations with other related constructs. The receiver operating characteristic curve analysis was used to determine an empirical cut-off point. Results Findings confirmed the single-factor structure of the instrument, its measurement invariance at the configural level, and the convergent and criterion validities. Satisfactory levels of reliability and a cut-off point of 21 were obtained. Discussion and conclusions The present study provides validity evidence for the use of the Italian version of the IGDS9-SF and may foster research into gaming addiction in the Italian context. PMID:27876422
Psychometric Properties of the Spanish Version of the Panic Disorder Severity Scale.
Fuste, Gideoni; Gil, María Ángeles; López-Solà, Clara; Rosado, Silvia; Bonillo, Albert; Pailhez, Guillem; Bulbena, Antoni; Pérez, Víctor; Fullana, Miguel A
2018-03-25
The Panic Disorder Severity Scale (PDSS) is a well-established measure of panic symptoms but few data exist on this instrument in non north-American samples. Our main goal was to assess the psychometric properties (internal consistency, test re-test reliability, inter-rater reliability, convergent and divergent validity) and the factor structure of the Spanish version. Ninety-four patients with a main diagnosis of panic disorder were assessed with the Spanish version of PDSS, the Anxiety Sensitivity Index-3 (ASI-3), the Panic and Agoraphobia Scale (PAS), the Beck Anxiety Inventory (BAI), the Beck Depression Inventory-II (BDI-II) the PDSS self-rating form and the Clinical Global Impression-Severity scale (CGI). The Spanish PDSS showed acceptable internal consistency (α = .74), excellent test-retest (total score and items 1-6: α > .58, p .90) and medium to large convergent validity (r = .68, 95% CI [.54, .79], p < .01; r = .80, 95% CI [.70, .87], p < .01; r = .48, 95% CI [.28, .67], p < .01; BAI, PAS and ASI-3 total scores respectively). Data on divergent validity (BDI-II total score: r = .52, 95% CI [.34, .67], p < .01) suggest some need for refinement of the PDSS. The confirmatory factor analysis suggested a two-factor modified model for the scale (nested χ2 = 14.01, df = 12, p < .001). The Spanish PDSS has similar psychometric properties as the previous versions and is a useful instrument to assess panic symptoms in clinical settings in Spanish-speaking populations.
Hashim, Hairul Anuar; Shaharuddin, Saidatin Sabiyah; Hamidan, Shazarina; Grove, J Robert
2017-02-01
This study examined psychometric properties of a Malaysian-language Sport Anxiety Scale-2 (SAS-2) in three separate studies. Study 1 examined the criterion validity and internal consistency of SAS-2 among 119 developmental hockey players. Measures of trait anxiety and mood states along with digit vigilance, choice reaction time, and depth perception tests were administered. Regression analysis revealed that somatic anxiety and concentration disruption were significantly associated with sustained attention. Worry was significantly associated with depth perception but not sustained attention. Pearson correlation coefficients also revealed significant relationships between SAS-2 subscales and negative mood state dimensions. Study 2 examined the convergent and discriminant validity of SAS-2 by correlating it with state anxiety measured by the CSAI-2R. Significant positive relationships were obtained between SAS-2 subscales and somatic and cognitive state anxiety. Conversely, state self-confidence was negatively related to SAS-2 subscales. In addition, significant differences were observed between men and women in somatic anxiety. Study 3 examined the factorial validity of the Malaysian SAS-2 using confirmatory factor analysis in a sample of 539 young athletes. Confirmatory factor analysis results provided strong support for the SAS-2 factor structure. Path loadings exceeding 0.5 indicated convergent validity among the subscales, and low to moderate subscale intercorrelations provided evidence of discriminant validity. Overall, the results supported the criterion and construct validity of this Malaysian-language SAS-2 instrument.
Validation of the Mini-OAKHQOL for use in patients with osteoarthritis in Spain.
Gonzalez Sáenz de Tejada, Marta; Bilbao, Amaia; Herrera, Carmen; García, Lidia; Sarasqueta, Cristina; Escobar, Antonio
2017-08-01
The Mini-Osteoarthritis Knee and Hip Quality of Life (Mini-OAKHQOL) questionnaire osteoarthritis is specific to individuals with knee or hip osteoarthritis. The objective of this study was to perform a validation of the Mini-OAKHQOL for use in Spain in terms of its psychometric properties of reliability, validity and responsiveness. Patients with osteoarthritis from the waiting list for a joint replacement completed the OAKHQOL, Short Form 36 Health Survey and Western Ontario and McMaster Universities Osteoarthritis Index. Reliability was assessed in terms of internal consistency and test-retest data, and convergent validity using Spearman's correlation coefficient. Structural validity was investigated by confirmatory factor analysis, and Rasch analysis was used to examine the unidimensionality of the scales. Responsiveness was assessed by calculating effect sizes. Confirmatory factor analysis confirmed the five-factor model, and the results of the Rasch analyses supported the unidimensionality assumption, with infit and outfit statistics. Cronbach's alpha ranged from 0.76 to 0.89 for all except the social dimensions. Statistically significant differences were observed between patients with different degrees of disease severity on all dimensions. There was convergent validity among dimensions expected to be correlated. The OAKHQOL questionnaire showed good responsiveness, with large changes for all dimensions apart from the two social dimensions, which had small effect sizes. Results of the study support the view that the Spanish version of the Mini-OAKHQOL questionnaire is a valid instrument to measure health-related quality of life in patients with osteoarthritis of the lower limb.
Assessing the Role of Spirituality in Coping Among African Americans Diagnosed with Cancer
Schulz, Emily; Caplan, Lee; Blake, Victor; Southward, Vivian L.; Buckner, Ayanna V.
2013-01-01
Spirituality plays an important role in cancer coping among African Americans. The purpose of this study was to report on the initial psychometric properties of instruments specific to the cancer context, assessing the role of spirituality in coping. Items were developed based on a theoretical model of spirituality and qualitative patient interviews. The instruments reflected connections to self, others, God, and the world. One hundred African American cancer survivors completed the instruments by telephone. The instruments showed adequate internal reliability, mixed convergent validity, discriminant validity, and interpretable factor structures. PMID:21246282
Sexual Expression and It's Determinants, in People Diagnosed with Psychotic Disorders.
de Jager, José; van Greevenbroek, Roos; Nugter, Annet; van Os, Jim
2018-05-18
This qualitative study aims to explore the difficulties people with a psychotic disorder have in sexual expression, and associated determinants. Twenty-eight semi-structured interviews were conducted and analyzed using the Grounded Theory method. Almost all participants experienced unfulfilled needs in sexual expression. These unfulfilled needs were associated with a range of factors, including antipsychotic medication, psychotic symptoms, sexual abuse, social skills and stigma, all of which may converge on a pathway involving (sexual) self-esteem. Further research is required to better understand the role of self-esteem in relation to sexual needs and expression in people with psychotic disorders.
Generalized fictitious methods for fluid-structure interactions: Analysis and simulations
NASA Astrophysics Data System (ADS)
Yu, Yue; Baek, Hyoungsu; Karniadakis, George Em
2013-07-01
We present a new fictitious pressure method for fluid-structure interaction (FSI) problems in incompressible flow by generalizing the fictitious mass and damping methods we published previously in [1]. The fictitious pressure method involves modification of the fluid solver whereas the fictitious mass and damping methods modify the structure solver. We analyze all fictitious methods for simplified problems and obtain explicit expressions for the optimal reduction factor (convergence rate index) at the FSI interface [2]. This analysis also demonstrates an apparent similarity of fictitious methods to the FSI approach based on Robin boundary conditions, which have been found to be very effective in FSI problems. We implement all methods, including the semi-implicit Robin based coupling method, in the context of spectral element discretization, which is more sensitive to temporal instabilities than low-order methods. However, the methods we present here are simple and general, and hence applicable to FSI based on any other spatial discretization. In numerical tests, we verify the selection of optimal values for the fictitious parameters for simplified problems and for vortex-induced vibrations (VIV) even at zero mass ratio ("for-ever-resonance"). We also develop an empirical a posteriori analysis for complex geometries and apply it to 3D patient-specific flexible brain arteries with aneurysms for very large deformations. We demonstrate that the fictitious pressure method enhances stability and convergence, and is comparable or better in most cases to the Robin approach or the other fictitious methods.
NASA Astrophysics Data System (ADS)
Kumar, Love; Sharma, Vishal; Singh, Amarpal
2018-02-01
Wireless sensor networks have tremendous applications, such as civil, military, and environmental monitoring. In most of the applications, sensor data are required to be propagated over the internet/core networks, which result in backhaul setback. Subsequently, there is a necessity to backhaul the sensed information of such networks together with prolonging of the transmission link. Passive optical network (PON) is next-generation access technology emerging as a potential candidate for convergence of the sensed data to the core system. Earlier, the work with single-optical line terminal-PON was demonstrated and investigated merely analytically. This work is an attempt to demonstrate a practical model of a bidirectional single-sink wireless sensor network-PON converged network in which the collected data from cluster heads are transmitted over PON networks. Further, modeled converged structure has been investigated under the influence of double, single, and tandem sideband modulation schemes incorporating a corresponding phase-delay to the sensor data entities that have been overlooked in the past. The outcome illustrates the successful fusion of the sensor data entities over PON with acceptable bit error rate and signal to noise ratio serving as a potential development in the sphere of such converged networks. It has also been revealed that the data entities treated with tandem side band modulation scheme help in improving the performance of the converged structure. Additionally, analysis for uplink transmission reported with queue theory in terms of time cycle, average time delay, data packet generation, and bandwidth utilization. An analytical analysis of proposed converged network shows that average time delay for data packet transmission is less as compared with time cycle delay.
Preliminary development of the adolescent students' basic psychological needs at school scale.
Tian, Lili; Han, Mengmeng; Huebner, E Scott
2014-04-01
The aim of the present study was to develop and provide evidence for the validity of a new measure of adolescent students' psychological need satisfaction at school, using a sample of Chinese students. We conducted four studies with four independent samples (total n = 1872). The first study aimed to develop items for the new instrument and to ascertain its factorial structure using exploratory factor analysis procedures. The second study aimed to examine the instrument's factorial structure using confirmatory factor analysis procedures as well as to assess its internal consistency reliability, convergent and divergent validity. The third study aimed to assess its measurement invariance across gender and age. The fourth study aimed to test its test-retest reliability over time and predictive validity. These preliminary results showed that the new instrument has promising psychometric properties. The potential contributions of the new instrument for future research and educational practices were discussed. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Evaluating the psychometric properties of the Polish version of the Body Appreciation Scale-2.
Razmus, Magdalena; Razmus, Wiktor
2017-12-01
This study aimed to investigate the factor structure and psychometric properties of a Polish version of the Body Appreciation Scale-2 (BAS-2; Tylka & Wood-Barcalow, 2015). Data were collected from 721 individuals residing in various regions of Poland. There were two subsamples (n=336, age M=34.95, SD=10.83; and n=385, age M=35.38, SD=10.83). Both principal-axis and confirmatory factor analyses supported the one-dimensional structure of BAS-2 scores. Moreover, full scalar invariance of the BAS-2 in Poland across sex was demonstrated. Scores on the Polish BAS-2 had adequate internal consistency. Convergent validity was demonstrated through significant correlations between BAS-2 scores and variables related to body image (body and appearance self-conscious emotions), well-being (self-esteem, positive affect, and positive orientation), and body mass index. These results indicate that the Polish BAS-2 is an appropriate and psychometrically-sound measure of body appreciation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Rodgers, Rachel F; Schaefer, Lauren M; Thompson, J Kevin; Girard, Marilou; Bertrand, Mélanie; Chabrol, Henri
2016-06-01
This study evaluated the psychometric properties of the Sociocultural Attitudes Towards Appearance Questionnaire-4 (SATAQ-4), a measure of internalization of societal appearance ideals, in French men and women. French college students completed a translation of the 22-item SATAQ-4 and measures of body image and eating concerns. Exploratory analyses among women (N=207) indicated a 20-item scale with the original five factors: Internalization: Thin/Low Body Fat, Internalization: Muscular/Athletic, Pressures: Family, Pressures: Media, Pressures: Peers. This structure was confirmed among a second sample of women (N=227). The SATAQ-4 scores revealed excellent reliability and convergent validity with body image and eating concern scores. A slightly modified factor structure emerged in men, with excellent reliability. Among men, the SATAQ-4 subscales were consistently associated with eating, and shape and weight concerns, although less consistently with general measures of body image. The French SATAQ-4 is a useful measure of internalization of appearance ideals. Copyright © 2016 Elsevier Ltd. All rights reserved.
Self-consistent field for fragmented quantum mechanical model of large molecular systems.
Jin, Yingdi; Su, Neil Qiang; Xu, Xin; Hu, Hao
2016-01-30
Fragment-based linear scaling quantum chemistry methods are a promising tool for the accurate simulation of chemical and biomolecular systems. Because of the coupled inter-fragment electrostatic interactions, a dual-layer iterative scheme is often employed to compute the fragment electronic structure and the total energy. In the dual-layer scheme, the self-consistent field (SCF) of the electronic structure of a fragment must be solved first, then followed by the updating of the inter-fragment electrostatic interactions. The two steps are sequentially carried out and repeated; as such a significant total number of fragment SCF iterations is required to converge the total energy and becomes the computational bottleneck in many fragment quantum chemistry methods. To reduce the number of fragment SCF iterations and speed up the convergence of the total energy, we develop here a new SCF scheme in which the inter-fragment interactions can be updated concurrently without converging the fragment electronic structure. By constructing the global, block-wise Fock matrix and density matrix, we prove that the commutation between the two global matrices guarantees the commutation of the corresponding matrices in each fragment. Therefore, many highly efficient numerical techniques such as the direct inversion of the iterative subspace method can be employed to converge simultaneously the electronic structure of all fragments, reducing significantly the computational cost. Numerical examples for water clusters of different sizes suggest that the method shall be very useful in improving the scalability of fragment quantum chemistry methods. © 2015 Wiley Periodicals, Inc.
Origin of weak lensing convergence peaks
NASA Astrophysics Data System (ADS)
Liu, Jia; Haiman, Zoltán
2016-08-01
Weak lensing convergence peaks are a promising tool to probe nonlinear structure evolution at late times, providing additional cosmological information beyond second-order statistics. Previous theoretical and observational studies have shown that the cosmological constraints on Ωm and σ8 are improved by a factor of up to ≈2 when peak counts and second-order statistics are combined, compared to using the latter alone. We study the origin of lensing peaks using observational data from the 154 deg2 Canada-France-Hawaii Telescope Lensing Survey. We found that while high peaks (with height κ >3.5 σκ , where σκ is the rms of the convergence κ ) are typically due to one single massive halo of ≈1 015M⊙ , low peaks (κ ≲σκ ) are associated with constellations of 2-8 smaller halos (≲1 013M⊙ ). In addition, halos responsible for forming low peaks are found to be significantly offset from the line of sight towards the peak center (impact parameter ≳ their virial radii), compared with ≈0.25 virial radii for halos linked with high peaks, hinting that low peaks are more immune to baryonic processes whose impact is confined to the inner regions of the dark matter halos. Our findings are in good agreement with results from the simulation work by Yang et al. [Phys. Rev. D 84, 043529 (2011)].
Stoner, Charlotte R; Orrell, Martin; Spector, Aimee
To conduct an in-depth psychometric assessment of the PPOM; a measure of hope and resilience. An observational study at five NHS trusts across England. Participants either completed the study using self-complete or interview led procedures, depending on their preference. Assessments were internal consistency, floor and ceiling effects, test-retest reliability, convergent validity and factor structure. 225 participants were recruited and completed the study, with a subsample of 48 comprising the test-retest sample. Internal consistency was excellent α = 0.94, and significant correlations were observed between quality of life (r = 0.627, p < .001), depression (r = -0.699, p < .001) and the Control, Autonomy, Self-realisation and Pleasure Scale (CASP-19; r = 0.73, p < .001). The PPOM remained moderately stable over a one week period (ICC: 880) and factor analyses indicated a two-factor structure solution with acceptable fit indices. The PPOM has robust psychometric properties and is now suitable for use research and practice. People who met the clinical criteria for depression were more likely to have lower scores on the PPOM, indicating criterion validity. Future work is needed to establish the PPOM as sensitive to change and to investigate the relationship between hope, resilience and depression further. Copyright © 2018 Elsevier B.V. All rights reserved.
Ross, Amy M; Ilic, Kelley; Kiyoshi-Teo, Hiroko; Lee, Christopher S
2017-12-26
The purpose of this study was to establish the psychometric properties of the new 16-item leadership environment scale. The leadership environment scale was based on complexity science concepts relevant to complex adaptive health care systems. A workforce survey of direct-care nurses was conducted (n = 1,443) in Oregon. Confirmatory factor analysis, exploratory factor analysis, concordant validity test and reliability tests were conducted to establish the structure and internal consistency of the leadership environment scale. Confirmatory factor analysis indices approached acceptable thresholds of fit with a single factor solution. Exploratory factor analysis showed improved fit with a two-factor model solution; the factors were labelled 'influencing relationships' and 'interdependent system supports'. Moderate to strong convergent validity was observed between the leadership environment scale/subscales and both the nursing workforce index and the safety organising scale. Reliability of the leadership environment scale and subscales was strong, with all alphas ≥.85. The leadership environment scale is structurally sound and reliable. Nursing management can employ adaptive complexity leadership attributes, measure their influence on the leadership environment, subsequently modify system supports and relationships and improve the quality of health care systems. The leadership environment scale is an innovative fit to complex adaptive systems and how nurses act as leaders within these systems. © 2017 John Wiley & Sons Ltd.
Mind Map Marketing: A Creative Approach in Developing Marketing Skills
ERIC Educational Resources Information Center
Eriksson, Lars Torsten; Hauer, Amie M.
2004-01-01
In this conceptual article, the authors describe an alternative course structure that joins learning key marketing concepts to creative problem solving. The authors describe an approach using a convergent-divergent-convergent (CDC) process: key concepts are first derived from case material to be organized in a marketing matrix, which is then used…
Distributed Sensing and Processing: A Graphical Model Approach
2005-11-30
that Ramanujan graph toplogies maximize the convergence rate of distributed detection consensus algorithms, improving over three orders of...small world type network designs. 14. SUBJECT TERMS Ramanujan graphs, sensor network topology, sensor network...that Ramanujan graphs, for which there are explicit algebraic constructions, have large eigenratios, converging much faster than structured graphs
Pinto, Anthony; Greenberg, Benjamin D.; Grados, Marco A.; Bienvenu, O. Joseph; Samuels, Jack F.; Murphy, Dennis L.; Hasler, Gregor; Stout, Robert L.; Rauch, Scott L.; Shugart, Yin Y.; Pauls, David L.; Knowles, James A.; Fyer, Abby J.; McCracken, James T.; Piacentini, John; Wang, Ying; Willour, Virginia L.; Cullen, Bernadette; Liang, Kung-Yee; Hoehn-Saric, Rudolf; Riddle, Mark A.; Rasmussen, Steven A.; Nestadt, Gerald
2008-01-01
Despite progress in identifying homogeneous subphenotypes of obsessive compulsive disorder (OCD) through factor analysis of the Yale-Brown Obsessive Compulsive Scale Symptom Checklist (YBOCS-SC), prior solutions have been limited by a reliance on presupposed symptom categories rather than discrete symptoms. Furthermore, there have been only limited attempts to evaluate the familiality of OCD symptom dimensions. The purpose of this study was to extend prior work by this collaborative group in category-based dimensions by conducting the first-ever exploratory dichotomous factor analysis using individual OCD symptoms, comparing these results to a refined category-level solution, and testing the familiality of derived factors. Participants were 485 adults in the six-site OCD Collaborative Genetics Study, diagnosed with lifetime OCD using semi-structured interviews. YBOCS-SC data were factor analyzed at both the individual item and symptom category levels. Factor score intraclass correlations were calculated using a subsample of 145 independent affected sib pairs. The item- and category-level factor analyses yielded nearly identical 5-factor solutions. While significant sib-sib associations were found for 4 of the 5 factors, Hoarding and Taboo Thoughts were the most robustly familial (rICC ≥ 0.2). This report presents considerable converging evidence for a 5-factor structural model of OCD symptoms, including separate factor analyses employing individual symptoms and symptom categories, as well as sibling concordance. The results support investigation of this multidimensional model in OCD genetic linkage studies. PMID:18514325
The Structure of Social Exchange in Self-Help Support Groups: Development of a Measure
Brown, Louis D.; Tang, Xiaohui; Hollman, Ruth L.
2014-01-01
Self-help support groups are indigenous community resources designed to help people manage a variety of personal challenges, from alcohol abuse to xeroderma pigmentosum. The social exchanges that occur during group meetings are central to understanding how people benefit from participation. This paper examines the different types of social exchange behaviors that occur during meetings, using two studies to develop empirically distinct scales that reliably measure theoretically important types of exchange. Resource theory informed the initial measurement development efforts. Exploratory factor analyses from the first study led to revisions in the factor structure of the social exchange scales. The revised measure captured the exchange of emotional support, experiential information, humor, unwanted behaviors, and exchanges outside meetings. Confirmatory factor analyses from a follow-up study with a different sample of self-help support groups provided good model fit, suggesting the revised structure accurately represented the data. Further, the scales demonstrated good convergent and discriminant validity with related constructs. Future research can use the scales to identify aspects of social exchange that are most important in improving health outcomes among self-help support group participants. Groups can use the scales in practice to celebrate strengths and address weaknesses in their social exchange dynamics. PMID:24398622
A superlinear convergence estimate for an iterative method for the biharmonic equation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Horn, M.A.
In [CDH] a method for the solution of boundary value problems for the biharmonic equation using conformal mapping was investigated. The method is an implementation of the classical method of Muskhelishvili. In [CDH] it was shown, using the Hankel structure, that the linear system in [Musk] is the discretization of the identify plus a compact operator, and therefore the conjugate gradient method will converge superlinearly. The purpose of this paper is to give an estimate of the superlinear convergence in the case when the boundary curve is in a Hoelder class.
NASA Technical Reports Server (NTRS)
Oden, J. Tinsley
1995-01-01
Underintegrated methods are investigated with respect to their stability and convergence properties. The focus was on identifying regions where they work and regions where techniques such as hourglass viscosity and hourglass control can be used. Results obtained show that underintegrated methods typically lead to finite element stiffness with spurious modes in the solution. However, problems exist (scalar elliptic boundary value problems) where underintegrated with hourglass control yield convergent solutions. Also, stress averaging in underintegrated stiffness calculations does not necessarily lead to stable or convergent stress states.
Psychometric Properties of the Children's Automatic Thoughts Scale (CATS) in Chinese Adolescents.
Sun, Ling; Rapee, Ronald M; Tao, Xuan; Yan, Yulei; Wang, Shanshan; Xu, Wei; Wang, Jianping
2015-08-01
The Children's Automatic Thoughts Scale (CATS) is a 40-item self-report questionnaire designed to measure children's negative thoughts. This study examined the psychometric properties of the Chinese translation of the CATS. Participants included 1,993 students (average age = 14.73) from three schools in Mainland China. A subsample of the participants was retested after 4 weeks. Confirmatory factor analysis replicated the original structure with four first-order factors loading on a single higher-order factor. The convergent and divergent validity of the CATS were good. The CATS demonstrated high internal consistency and test-retest reliability. Boys scored higher on the CATS-hostility subscale, but there were no other gender differences. Older adolescents (15-18 years) reported higher scores than younger adolescents (12-14 years) on the total score and on the physical threat, social threat, and hostility subscales. The CATS proved to be a reliable and valid measure of automatic thoughts in Chinese adolescents.
Composite transform-convergent plate boundaries: description and discussion
Ryan, H.F.; Coleman, P.J.
1992-01-01
The leading edge of the overriding plate at an obliquely convergent boundary is commonly sliced by a system of strike-slip faults. This fault system is often structurally complex, and may show correspondingly uneven strain effects, with great vertical and translational shifts of the component blocks of the fault system. The stress pattern and strain effects vary along the length of the system and change through time. These margins are considered to be composite transform-convergent (CTC) plate boundaries. Examples are given of structures formed along three CTC boundaries: the Aleutian Ridge, the Solomon Islands, and the Philippines. The dynamism of the fault system along a CTC boundary can enhance vertical tectonism and basin formation. This concept provides a framework for the evaluation of petroleum resources related to basin formation, and mineral exploration related to igneous activity associated with transtensional processes. ?? 1992.
Fortuna Tessera, Venus - Evidence of horizontal convergence and crustal thickening
NASA Technical Reports Server (NTRS)
Vorder Bruegge, R. W.; Head, J. W.
1989-01-01
Structural and tectonic patterns mapped in Fortuna Tessera are interpreted to reflect a change in the style and intensity of deformation from east to west, beginning with simple tessera terrain at relatively low topographic elevations in the east and progressing through increasingly complex deformation patterns and higher topography to Maxwell Montes in the West. These morphologic and topographic patterns are consistent with east-to-west convergence and compression and the increasing elevations are interpreted to be due to crustal thickening processes associated with the convergent deformational environment. Using an Airy isostatic model, crustal thicknesses of approximately 35 km for the initial tessera terrain, and crustal thicknesses of over 100 km for the Maxwell Montes region are predicted. Detailed mapping with Magellan data will permit the deconvolution of individual components and structures in this terrain.
Acoustic echo cancellation for full-duplex voice transmission on fading channels
NASA Technical Reports Server (NTRS)
Park, Sangil; Messer, Dion D.
1990-01-01
This paper discusses the implementation of an adaptive acoustic echo canceler for a hands-free cellular phone operating on a fading channel. The adaptive lattice structure, which is particularly known for faster convergence relative to the conventional tapped-delay-line (TDL) structure, is used in the initialization stage. After convergence, the lattice coefficients are converted into the coefficients for the TDL structure which can accommodate a larger number of taps in real-time operation due to its computational simplicity. The conversion method of the TDL coefficients from the lattice coefficients is derived and the DSP56001 assembly code for the lattice and TDL structure is included, as well as simulation results and the schematic diagram for the hardware implementation.
Litt, Mark D.; Kadden, Ronald M; Tennen, Howard
2012-01-01
The Coping Strategies Scale (CSS) was designed to assess adaptive changes in substance-use specific coping that result from treatment. The present study sought to examine the latent structure of the CSS in the hope that it might shed light on the coping processes of drug users, and guide the development of a brief version of the CSS. Respondents on the CSS were 751 men and women treated in three clinical trials for marijuana dependence. Posttreatment CSS data were analyzed to determine the nature of coping responses in patients who have been trained to use specific strategies to deal with substance use disorders. Exploratory factor analysis yielded two factors, categorized as problem-focused and emotion-focused coping, but confirmatory factor analysis did not support this structure. When infrequently endorsed items were removed, however, confirmatory factor analysis revealed a good fit to the data. Contrary to expectations, practical strategies that often form the basis for coping skills training, such as avoiding those who smoke, were not frequently endorsed. Problem focused items reflected cognitive commitments to change. Emotion-focused items included cognitive reinterpretations of emotions, to help manage emotional reactions. Brief versions of the CSS based on these factors showed good convergent and discriminant validity. The CSS, and the brief versions of the CSS, may prove useful in future treatment trials to evaluate effects of treatment on coping skills acquisition and utilization in substance dependent individuals. PMID:22082345
Structure and strategy in encoding simplified graphs
NASA Technical Reports Server (NTRS)
Schiano, Diane J.; Tversky, Barbara
1992-01-01
Tversky and Schiano (1989) found a systematic bias toward the 45-deg line in memory for the slopes of identical lines when embedded in graphs, but not in maps, suggesting the use of a cognitive reference frame specifically for encoding meaningful graphs. The present experiments explore this issue further using the linear configurations alone as stimuli. Experiments 1 and 2 demonstrate that perception and immediate memory for the slope of a test line within orthogonal 'axes' are predictable from purely structural considerations. In Experiments 3 and 4, subjects were instructed to use a diagonal-reference strategy in viewing the stimuli, which were described as 'graphs' only in Experiment 3. Results for both studies showed the diagonal bias previously found only for graphs. This pattern provides converging evidence for the diagonal as a cognitive reference frame in encoding linear graphs, and demonstrates that even in highly simplified displays, strategic factors can produce encoding biases not predictable solely from stimulus structure alone.
Listening, watching, and reading: the structure and correlates of entertainment preferences.
Rentfrow, Peter J; Goldberg, Lewis R; Zilca, Ran
2011-04-01
People spend considerable amounts of time and money listening to music, watching TV and movies, and reading books and magazines, yet almost no attention in psychology has been devoted to understanding individual differences in preferences for such entertainment. The present research was designed to examine the structure and correlates of entertainment genre preferences. Analyses of the genre preferences of more than 3,000 individuals revealed a remarkably clear factor structure. Using multiple samples, methods, and geographic regions, data converged to reveal five entertainment-preference dimensions: Communal, Aesthetic, Dark, Thrilling, and Cerebral. Preferences for these entertainment dimensions were uniquely related to demographics and personality traits. Results also indicated that personality accounted for significant proportions of variance in entertainment preferences over and above demographics. The results provide a foundation for developing and testing hypotheses about the psychology of entertainment preferences. © 2011 The Authors. Journal of Personality © 2011, Wiley Periodicals, Inc.
High-performance equation solvers and their impact on finite element analysis
NASA Technical Reports Server (NTRS)
Poole, Eugene L.; Knight, Norman F., Jr.; Davis, D. Dale, Jr.
1990-01-01
The role of equation solvers in modern structural analysis software is described. Direct and iterative equation solvers which exploit vectorization on modern high-performance computer systems are described and compared. The direct solvers are two Cholesky factorization methods. The first method utilizes a novel variable-band data storage format to achieve very high computation rates and the second method uses a sparse data storage format designed to reduce the number of operations. The iterative solvers are preconditioned conjugate gradient methods. Two different preconditioners are included; the first uses a diagonal matrix storage scheme to achieve high computation rates and the second requires a sparse data storage scheme and converges to the solution in fewer iterations that the first. The impact of using all of the equation solvers in a common structural analysis software system is demonstrated by solving several representative structural analysis problems.
High-performance equation solvers and their impact on finite element analysis
NASA Technical Reports Server (NTRS)
Poole, Eugene L.; Knight, Norman F., Jr.; Davis, D. D., Jr.
1992-01-01
The role of equation solvers in modern structural analysis software is described. Direct and iterative equation solvers which exploit vectorization on modern high-performance computer systems are described and compared. The direct solvers are two Cholesky factorization methods. The first method utilizes a novel variable-band data storage format to achieve very high computation rates and the second method uses a sparse data storage format designed to reduce the number od operations. The iterative solvers are preconditioned conjugate gradient methods. Two different preconditioners are included; the first uses a diagonal matrix storage scheme to achieve high computation rates and the second requires a sparse data storage scheme and converges to the solution in fewer iterations that the first. The impact of using all of the equation solvers in a common structural analysis software system is demonstrated by solving several representative structural analysis problems.
Mauro, John C; Loucks, Roger J; Balakrishnan, Jitendra; Raghavan, Srikanth
2007-05-21
The thermodynamics and kinetics of a many-body system can be described in terms of a potential energy landscape in multidimensional configuration space. The partition function of such a landscape can be written in terms of a density of states, which can be computed using a variety of Monte Carlo techniques. In this paper, a new self-consistent Monte Carlo method for computing density of states is described that uses importance sampling and a multiplicative update factor to achieve rapid convergence. The technique is then applied to compute the equilibrium quench probability of the various inherent structures (minima) in the landscape. The quench probability depends on both the potential energy of the inherent structure and the volume of its corresponding basin in configuration space. Finally, the methodology is extended to the isothermal-isobaric ensemble in order to compute inherent structure quench probabilities in an enthalpy landscape.
NASA Technical Reports Server (NTRS)
Brand, J. C.
1985-01-01
Contraction theory is applied to an iterative formulation of electromagnetic scattering from periodic structures and a computational method for insuring convergence is developed. A short history of spectral (or k-space) formulation is presented with an emphasis on application to periodic surfaces. The mathematical background for formulating an iterative equation is covered using straightforward single variable examples including an extension to vector spaces. To insure a convergent solution of the iterative equation, a process called the contraction corrector method is developed. Convergence properties of previously presented iterative solutions to one-dimensional problems are examined utilizing contraction theory and the general conditions for achieving a convergent solution are explored. The contraction corrector method is then applied to several scattering problems including an infinite grating of thin wires with the solution data compared to previous works.
Persistent Differences in Mortality Patterns across Industrialized Countries
d'Albis, Hippolyte; Esso, Loesse Jacques; Pifarré i Arolas, Héctor
2014-01-01
The epidemiological transition has provided the theoretical background for the expectation of convergence in mortality patterns. We formally test and reject the convergence hypothesis for a sample of industrialized countries in the period from 1960 to 2008. After a period of convergence in the decade of 1960 there followed a sustained process of divergence with a pronounced increase at the end of the 1980's, explained by trends within former Socialist countries (Eastern countries). While Eastern countries experienced abrupt divergence after the dissolution of the Soviet Union, differences within Western countries remained broadly constant for the whole period. Western countries transitioned from a strong correlation between life expectancy and variance in 1960 to no association between both moments in 2008 while Eastern countries experienced the opposite evolution. Taken together, our results suggest that convergence can be better understood when accounting for shared structural similarities amongst groups of countries rather than through global convergence. PMID:25181447
Pestle, Sarah L; Chorpita, Bruce F; Schiffman, Jason
2008-04-01
The Penn State Worry Questionnaire for Children (PSWQ-C; Chorpita, Tracey, Brown, Collica, & Barlow, 1997) is a 14-item self-report measure of worry in children and adolescents. Although the PSWQ-C has demonstrated favorable psychometric properties in small clinical and large community samples, this study represents the first psychometric evaluation of the PSWQ-C in a large clinical sample (N = 491). Factor analysis indicated a two-factor structure, in contrast to all previously published findings on the measure. The PSWQ-C demonstrated favorable psychometric properties in this sample, including high internal consistency, high convergent validity with related constructs, and acceptable discriminative validity between diagnostic categories. The performance of the 3 reverse-scored items was closely examined, and results indicated retaining all 14 items.
Briley, Daniel A.; Domiteaux, Matthew; Tucker-Drob, Elliot M.
2014-01-01
Many achievement-relevant personality measures (APMs) have been developed, but the interrelations among APMs or associations with the broader personality landscape are not well-known. In Study 1, 214 participants were measured on 36 APMs and a measure of the Big Five. Factor analytic results supported the convergent and discriminant validity of five latent dimensions: performance, mastery, self-doubt, effort, and intellectual investment. Conscientiousness, neuroticism, and openness to experience had the most consistent associations with APMs. We constructed a more efficient scale– the Multidimensional Achievement-Relevant Personality Scale (MAPS). In Study 2, we replicated the factor structure and external correlates of the MAPS in a sample of 359 individuals. Finally, we validated the MAPS with four indicators of academic performance and demonstrated incremental validity. PMID:24839374
Fernández-Domínguez, Juan Carlos; de Pedro-Gómez, Joan Ernest; Morales-Asencio, José Miguel; Sastre-Fullana, Pedro; Sesé-Abad, Albert
2017-01-01
Introduction Most of the EBP measuring instruments available to date present limitations both in the operationalisation of the construct and also in the rigour of their psychometric development, as revealed in the literature review performed. The aim of this paper is to provide rigorous and adequate reliability and validity evidence of the scores of a new transdisciplinary psychometric tool, the Health Sciences Evidence-Based Practice (HS-EBP), for measuring the construct EBP in Health Sciences professionals. Methods A pilot study and a subsequent two-stage validation test sample were conducted to progressively refine the instrument until a reduced 60-item version with a five-factor latent structure. Reliability was analysed through both Cronbach’s alpha coefficient and intraclass correlations (ICC). Latent structure was contrasted using confirmatory factor analysis (CFA) following a model comparison aproach. Evidence of criterion validity of the scores obtained was achieved by considering attitudinal resistance to change, burnout, and quality of professional life as criterion variables; while convergent validity was assessed using the Spanish version of the Evidence-Based Practice Questionnaire (EBPQ-19). Results Adequate evidence of both reliability and ICC was obtained for the five dimensions of the questionnaire. According to the CFA model comparison, the best fit corresponded to the five-factor model (RMSEA = 0.049; CI 90% RMSEA = [0.047; 0.050]; CFI = 0.99). Adequate criterion and convergent validity evidence was also provided. Finally, the HS-EBP showed the capability to find differences between EBP training levels as an important evidence of decision validity. Conclusions Reliability and validity evidence obtained regarding the HS-EBP confirm the adequate operationalisation of the EBP construct as a process put into practice to respond to every clinical situation arising in the daily practice of professionals in health sciences (transprofessional). The tool could be useful for EBP individual assessment and for evaluating the impact of specific interventions to improve EBP. PMID:28486533
Fernández-Domínguez, Juan Carlos; de Pedro-Gómez, Joan Ernest; Morales-Asencio, José Miguel; Bennasar-Veny, Miquel; Sastre-Fullana, Pedro; Sesé-Abad, Albert
2017-01-01
Most of the EBP measuring instruments available to date present limitations both in the operationalisation of the construct and also in the rigour of their psychometric development, as revealed in the literature review performed. The aim of this paper is to provide rigorous and adequate reliability and validity evidence of the scores of a new transdisciplinary psychometric tool, the Health Sciences Evidence-Based Practice (HS-EBP), for measuring the construct EBP in Health Sciences professionals. A pilot study and a subsequent two-stage validation test sample were conducted to progressively refine the instrument until a reduced 60-item version with a five-factor latent structure. Reliability was analysed through both Cronbach's alpha coefficient and intraclass correlations (ICC). Latent structure was contrasted using confirmatory factor analysis (CFA) following a model comparison aproach. Evidence of criterion validity of the scores obtained was achieved by considering attitudinal resistance to change, burnout, and quality of professional life as criterion variables; while convergent validity was assessed using the Spanish version of the Evidence-Based Practice Questionnaire (EBPQ-19). Adequate evidence of both reliability and ICC was obtained for the five dimensions of the questionnaire. According to the CFA model comparison, the best fit corresponded to the five-factor model (RMSEA = 0.049; CI 90% RMSEA = [0.047; 0.050]; CFI = 0.99). Adequate criterion and convergent validity evidence was also provided. Finally, the HS-EBP showed the capability to find differences between EBP training levels as an important evidence of decision validity. Reliability and validity evidence obtained regarding the HS-EBP confirm the adequate operationalisation of the EBP construct as a process put into practice to respond to every clinical situation arising in the daily practice of professionals in health sciences (transprofessional). The tool could be useful for EBP individual assessment and for evaluating the impact of specific interventions to improve EBP.
A contracting-interval program for the Danilewski method. Ph.D. Thesis - Va. Univ.
NASA Technical Reports Server (NTRS)
Harris, J. D.
1971-01-01
The concept of contracting-interval programs is applied to finding the eigenvalues of a matrix. The development is a three-step process in which (1) a program is developed for the reduction of a matrix to Hessenberg form, (2) a program is developed for the reduction of a Hessenberg matrix to colleague form, and (3) the characteristic polynomial with interval coefficients is readily obtained from the interval of colleague matrices. This interval polynomial is then factored into quadratic factors so that the eigenvalues may be obtained. To develop a contracting-interval program for factoring this polynomial with interval coefficients it is necessary to have an iteration method which converges even in the presence of controlled rounding errors. A theorem is stated giving sufficient conditions for the convergence of Newton's method when both the function and its Jacobian cannot be evaluated exactly but errors can be made proportional to the square of the norm of the difference between the previous two iterates. This theorem is applied to prove the convergence of the generalization of the Newton-Bairstow method that is used to obtain quadratic factors of the characteristic polynomial.
Castejón, Vanessa; Rovira, Tatiana; Sumalla, Enric C; Darder, Esther; Iglesias, Silvia; Ochoa, Cristian; Blanco, Ignacio
2016-02-19
Having an inherited predisposition to cancer may have a psychological impact, and one goal of genetic counseling is to promote psychological adjustment to the new situation. Thus, in the genetic context, validated measures of adjustment are required. Given that self-concept is a good indicator of adjustment to the disease or to the risk for it, and a relevant variable in oncology, the goal of the study is to culturally adapt and validate the BRCA Self-Concept Scale. One hundred and sixty-five BRCA carriers' women answered to the questionnaire, previously adapted through a process of forward/back-translation, and to the Cancer Worry Scale (CWS) as a measure of convergent validity. Theoretical structure of BRCA Self-Concept Scale was assessed by expert judges, and submitted to a confirmatory factor analysis (CFA). Cronbach's α was calculated for each subscale (Stigma, Vulnerability and Control), and correlations with CWS were performed. Expert judges' structure and CFA do not support the original structure of the questionnaire. The respecificity model (with items 10 and 13 loading on Vulnerability factor) show a better fit: comparative fit index 0.973; Tucker-Lewis index 0.968; root mean square error of approximation 0.067. The Cronbach's α is 0.83 for Stigma, 0.84 for Vulnerability, and 0.61 for Control. Evidence of convergent validity with CWS has been obtained (Spearman's rho 0.631 for Stigma, 0.683 for Vulnerability, and -0.363 for Control; P<.001). Results support the validity of the modified Spanish BRCA Self-Concept Scale, which is a potentially useful measure for the study of psychological adjustment to high risk for hereditary breast and ovarian cancer. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.
The convergence of Chinese county government health expenditures: capitation and contribution.
Zhang, Guoying; Zhang, Luwen; Wu, Shaolong; Xia, Xiaoqiong; Lu, Liming
2016-08-19
The disparity between government health expenditures across regions is more severe in developing countries than it is in developed countries. The capitation subsidy method has been proven effective in developed countries in reducing this disparity, but it has not been tested in China, the world's largest developing country. The convergence method of neoclassical economics was adopted to test the convergence of China's regional government health expenditure. Data were obtained from Provinces, Prefectures and Counties Fiscal Statistical Yearbook (2003-2007) edited by the Chinese Ministry of Finance, and published by the Chinese Finance & Economics Publishing House. The existence of σ-convergence and long-term and short-term β-convergence indicated the effectiveness of the capitation subsidy method in the New Rural Cooperative Medical Scheme on narrowing county government health expenditure disparities. The supply-side variables contributed the most to the county government health expenditure convergence, and factors contributing to convergence of county government health expenditures per capita were different in three regions. The narrowing disparity between county government health expenditures across regions supports the effectiveness of the capitation subsidy method adopted by China's New Rural Cooperative Scheme. However, subsidy policy still requires further improvement.
ERIC Educational Resources Information Center
MCNARY, SHIRLEY R.
THE RELATIONSHIP BETWEEN TEACHER CHARACTERISTICS AND THE DEGREE OF CHANGE SHOWN BY GIFTED ELEMENTARY PUPILS IN CONVERGENT AND DIVERGENT THINKING AREAS WAS INVESTIGATED. CHARACTERISTICS WERE ASSESSED BY MEASURES OF INTELLIGENCE, PERSONALITY FACTORS, AND A PERSONAL INFORMATION QUESTIONNAIRE. SIX PRE- AND POST-TESTS OF CONVERGENT AND 4 TESTS OF…
Jovanović, Veljko
2016-12-01
The validity of the life satisfaction measures commonly used among adults has been rarely examined in adolescent samples. The present research had two main goals: (1) to evaluate the structural validity of the Satisfaction with Life Scale (SWLS) among adolescents and to test measurement invariance across gender; (2) to compare the criterion and convergent validity of the SWLS and single-item life satisfaction measures among adolescents. Three samples of Serbian adolescents were recruited for the present research. Study 1 (N = 481, M age = 17.01 years) examined the structure of the SWLS via confirmatory factor analysis (CFA) and evaluated measurement invariance of the SWLS across gender by a multi-group CFA. Study 2 (N = 283, M age = 17.34 years) and Study 3 (N = 220, M age = 16.73 years) compared the convergent validity of the SWLS and single-item life satisfaction measures. The results of Study 1 supported the original one-factor model of the SWLS among adolescents and provided evidence for strong measurement invariance of the SWLS across gender. The findings of Study 2 and Study 3 showed that the SWLS and single-item measures were equally valid and strongly associated (r = .734 in Study 2 and r = .668 in Study 3). No substantial differences in correlations with school success and well-being indicators were found between the SWLS and single-item measures. Our findings support the use of the SWLS among adolescents and indicate that single-item life satisfaction measures perform as well as the SWLS in adolescent samples.
van Weert, Julia C M; Jansen, Jesse; de Bruijn, Gert-Jan; Noordman, Janneke; van Dulmen, Sandra; Bensing, Jozien M
2009-11-01
Knowing patients' needs is a prerequisite to ensure high quality cancer care. This study describes the development and psychometric properties of a patient-centred instrument to measure needs and actual experiences with communication preceding chemotherapy treatment: QUOTE(chemo). QUOTE-questionnaires (Quality Of care Through the patients' Eyes) are widely used to gain insight into unmet needs, but no validated, standardised questionnaire combining patients' needs and experiences surrounding chemotherapy treatment is available yet. To evaluate the psychometric properties of the QUOTE(chemo), content validity, internal structure and convergent validity were investigated amongst 345 cancer patients, new to chemotherapy, from 10 different hospitals. Literature study, focus group discussions and a categorisation procedure of 67 relevant topics revealed seven main themes: Treatment-related information, Prognosis information, Rehabilitation information, Coping information, Interpersonal communication, Tailored communication and Affective communication. Confirmatory factor analysis using structural equation modelling indicated that the measurement model provided good fit to the data with factor loadings ranging from .43 to .77. The seven QUOTE(chemo) dimensions captured relevant issues of concern with good internal consistency (alpha .72-.92), satisfactory item-total correlations (.35-.79) and satisfactory convergent validity. Affective communication, Treatment-related information and Rehabilitation information were perceived most important by patients. The instrument also appeared to be able to determine which aspects need improvement to ensure high quality care. The highest need for improvement was found for communicating Prognosis information and Rehabilitation information and for Interpersonal communication. These findings provide preliminary evidence of the reliability and validity of the QUOTE(chemo) for use in cancer care surrounding chemotherapy treatment. Researchers and health care providers can use the instrument to measure patients' needs and experiences with communication to identify aspects that need improvement.
Kaneko, Mei; Sato, Iori; Soejima, Takafumi; Kamibeppu, Kiyoko
2014-09-01
The purpose of the study is to develop a Japanese version of the Pediatric Quality of Life Inventory (PedsQL) Generic Core Scales Young Adult Version (PedsQL-YA-J) and determine the feasibility, reliability, and validity of the scales. Translation equivalence and content validity were verified using back-translation and cognitive debriefing tests. A total of 428 young adults recruited from one university, two vocational schools, or five companies completed questionnaires. We determined questionnaire feasibility, internal consistency, and test-retest reliability; checked concurrent validity against the Center for Epidemiologic Studies Depression Scale (CES-D); determined convergent and discriminant validity with the Medical Outcome Study 36-item Short Form Health Survey (SF-36); described known-groups validity with regard to subjective symptoms, illness or injury requiring regular medical visits, and depression; and verified factorial validity. All scales were internally consistent (Cronbach's coefficient alpha = 0.77-0.86); test-retest reliability was acceptable (intraclass correlation coefficient = 0.57-0.69); and all scales were concurrently valid with depression (Pearson's correlation coefficient = 0.43-0.57). The scales convergent and discriminant validity with the SF-36 and CES-D were acceptable. Evaluation of known-groups validity confirmed that the Physical Functioning scale was sensitive for subjective symptoms, the Emotional Functioning scale for depression, and the Work/School Functioning scale for illness or injury requiring regular medical visits. Exploratory factor analysis found a six-factor structure consistent with the assumed structure (cumulative proportion = 57.0%). The PedsQL-YA-J is suitable for assessing health-related quality of life in young adults in education, employment, or training, and for clinical trials and epidemiological research.
Dubé, Laurette; Webb, Patrick; Arora, Narendra K; Pingali, Prabhu
2014-12-01
The causes of many vexing challenges facing 21st-century society are at the nexus of systems involved in agriculture, health and wealth production, consumption, and distribution. Using food as a test bed, and on the basis of emerging roadmaps that set achievable objectives over a 1- to 3-year horizon, we introduce this special feature with convergence thinking and practice at its core. Specifically, we discuss academic papers structured around four themes: (1) evidence for a need for convergence and underlying mechanisms at the individual and societal levels; (2) strategy for mainstreaming convergence as a driver of business engagement and innovation; (3) convergence in policy and governance; (4) convergence in metrics and methods. Academic papers under each theme are accompanied by a roadmap paper reporting on the current status of concrete transformative convergence-building projects associated with that theme. We believe that the insights provided by these papers have the potential to enable all actors throughout society to singly and collectively work to build supply and demand for nutritious food, in both traditional and modern food systems, while placing the burdens of malnutrition and ill health on their core strategic agendas. © 2014 New York Academy of Sciences.
Young, Kyle A.; Snoeks, Jos; Seehausen, Ole
2009-01-01
Background Deterministic evolution, phylogenetic contingency and evolutionary chance each can influence patterns of morphological diversification during adaptive radiation. In comparative studies of replicate radiations, convergence in a common morphospace implicates determinism, whereas non-convergence suggests the importance of contingency or chance. Methodology/Principal Findings The endemic cichlid fish assemblages of the three African great lakes have evolved similar sets of ecomorphs but show evidence of non-convergence when compared in a common morphospace, suggesting the importance of contingency and/or chance. We then analyzed the morphological diversity of each assemblage independently and compared their axes of diversification in the unconstrained global morphospace. We find that despite differences in phylogenetic composition, invasion history, and ecological setting, the three assemblages are diversifying along parallel axes through morphospace and have nearly identical variance-covariance structures among morphological elements. Conclusions/Significance By demonstrating that replicate adaptive radiations are diverging along parallel axes, we have shown that non-convergence in the common morphospace is associated with convergence in the global morphospace. Applying these complimentary analyses to future comparative studies will improve our understanding of the relationship between morphological convergence and non-convergence, and the roles of contingency, chance and determinism in driving morphological diversification. PMID:19270732
NASA Astrophysics Data System (ADS)
Sadeghi, Shahriar; Yassaghi, Ali
2016-04-01
Stratigraphy, detailed structural mapping and a crustal-scale cross section across the NW Zagros collision zone provide constraints on the spatial evolution of oblique convergence of the Arabian and Eurasian plates since the Late Cretaceous. The Zagros collision zone in NW Iran consists of the internal Sanandaj-Sirjan, Gaveh Rud and Ophiolite zones and the external Bisotoun, Radiolarite and High Zagros zones. The Main Zagros Thrust is the major structure of the Zagros suture zone. Two stages of oblique deformation are recognized in the external part of the NW Zagros in Iran. In the early stage, coexisting dextral strike-slip and reverse dominated domains in the Radiolarite zone developed in response to deformation partitioning due to oblique convergence. Dextral-reverse faults in the Bisotoun zone are also compatible with oblique convergence. In the late stage, deformation partitioning occurred during southeastward propagation of the Zagros orogeny towards its foreland resulting in synchronous development of orogen-parallel strike-slip and thrust faults. It is proposed that the first stage was related to Late Cretaceous oblique obduction, while the second stage resulted from Cenozoic collision. The Cenozoic orogen-parallel strike-slip component of Zagros oblique convergence is not confined to the Zagros suture zone (Main Recent Fault) but also occurred in the external part (Marekhil-Ravansar fault system). Thus, it is proposed that oblique convergence of Arabian and Eurasian plates in Zagros collision zone initiated with oblique obduction in the Late Cretaceous followed by oblique collision in the late Tertiary, consistent with global plate reconstructions.
Omoto, Kenichiro; Hosono, Nobuhiko; Gochomori, Mika; Albrecht, Ken; Yamamoto, Kimihisa; Kitagawa, Susumu
2018-05-17
Anisotropic dendrimers with bipolar shapes were systematically obtained using a heteroleptic metal-organic polyhedron (MOP) as a robust core scaffold. The structure of one of these polyhedral shapes was unambiguously determined by single-crystal X-ray analysis, which revealed that the bulky dendrons converge to both axial positions of the heteroleptic MOP core.
Factorial structure and convergent and discriminant validity of the E (Empathy) scale.
Tran, Ulrich S; Laireiter, Anton-Rupert; Schmitt, David P; Neuner, Christine; Leibetseder, Max; Szente-Voracek, Sara Leyla; Voracek, Martin
2013-10-01
The Empathy (E) scale has been proposed as a theoretically and psychometrically more satisfying alternative to existing self-report measures of empathy. Its four scales (facets) cover both components (cognitive vs. emotional) and both reality statuses (fictitious vs. real-life) of empathy in pairwise combinations. Confirmatory factor analyses of the E-scale in an Austrian community sample (N = 794) suggested that one prior assumption, namely the mutual orthogonality of these facets, may partly need revision; particularly, the E-scale facets seemed to reflect more strongly differences in the reality statuses than in the components of empathy. Utilizing numerous informative psychological traits, the scale's convergent and discriminant validity were examined. E-scale scores were consistently predicted by sex-related and relationship-related constructs and measures of antisocial attitudes and behavior. Among the Big Five personality dimensions, openness emerged as a major positive correlate of empathy. Sex and age were demographic correlates of E-scale scores (higher in women and the younger). Findings were discussed with regards to the definition and measurement of empathy.
Caballo, Vicente E.; Arias, Benito; Salazar, Isabel C.; Irurtia, María Jesús; Hofmann, Stefan G.
2015-01-01
This paper presents the psychometric properties of a new measure of social anxiety, the Social Anxiety Questionnaire for adults (SAQ), composed of 30 items that were developed based on participants from 16 Latin American countries, Spain, and Portugal. Two groups of participants were included in the study: a non-clinical group involving 18,133 persons and a clinical group comprising 334 patients with a diagnosis of social anxiety disorder (social phobia). Exploratory and confirmatory factor analyses supported a 5-factor structure of the questionnaire. The factors were labeled: 1) Interactions with strangers, 2) Speaking in public/talking with people in authority, 3) Interactions with the opposite sex, 4) Criticism and embarrassment, and 5) Assertive expression of annoyance, disgust or displeasure. Psychometric evidence supported the internal consistency, convergent validity, and measurement invariance of the SAQ. To facilitate clinical applications, a ROC analysis identified cut scores for men and women for each factor and for the global score. PMID:25774643
Moshier, Samantha J; Landau, Aaron J; Hearon, Bridget A; Stein, Aliza T; Greathouse, Lee; Smits, Jasper A J; Otto, Michael W
2016-01-01
Compensatory eating in response to exercise may be an obstacle to achieving weight-loss and fitness goals. In this study we develop and conduct a preliminary examination of the psychometric properties of the Compensatory Eating Motives Questionnaire (CEMQ), a self-report questionnaire of motives for compensatory eating. Development and testing of the CEMQ was conducted in two student samples. Of respondents, 75% reported engaging in compensatory eating. Factor analysis yielded factors representing three domains of motives for compensatory eating: Eating for Reward, Eating for Recovery, and Eating for Relief. Internal consistency of the factors was adequate, and the factor structure was replicated. Correlations between the CEMQ subscales and trait questionnaires supported hypotheses for convergent and divergent validity. These results encourage further investigation of compensatory eating as a potential obstacle to weight loss, and support the continued assessment of the CEMQ as a tool to measure three conceptually distinct motives for compensatory eating.
Measuring hope among families impacted by cognitive impairment.
Hunsaker, Amanda E; Terhorst, Lauren; Gentry, Amanda; Lingler, Jennifer H
2016-07-01
The current exploratory investigation aims to establish the reliability and validity of a hope measure, the Herth Hope Index, among families impacted by early cognitive impairment (N = 96). Exploratory factor analysis was used to examine the dimensionality of the measure. Bivariate analyses were used to examine construct validity. The sample had moderately high hope scores. A two-factor structure emerged from the factor analysis, explaining 51.44% of the variance. Both factors exhibited strong internal consistency (Cronbach's alphas ranged from .83 to .86). Satisfaction with social support was positively associated with hope, supporting convergent validity. Neurocognitive status, illness insight, and depression were not associated with hope, indicating discriminant validity. Families impacted by cognitive impairment may maintain hope in the face of a potentially progressive illness, regardless of cognitive status. The Herth Hope Index can be utilized as a reliable and valid measure of hope by practitioners providing support to families impacted by cognitive impairment. © The Author(s) 2014.
Assessment of children's emotional adjustment: construction and validation of a new instrument.
Thorlacius, Ö; Gudmundsson, E
2015-09-01
The present study describes the Children's Emotional Adjustment Scale (CEAS), a 47-item parent-reported scale designed to capture children's emotional functioning on four continuous dimensions. A large community sample of mothers of children (n = 606) aged 6-13 years was used to examine the psychometric properties of the CEAS. Exploratory and confirmatory factor analysis supported the hypothesized four-factor structure of the instrument: (1) temper control; (2) anxiety control; (3) mood repair; and (4) social assertiveness. Cronbach's alphas for the factors were consistently above 0.90, and convergent validity of the factors was satisfactory with maternal ratings of child psychopathology. Children rated by their mothers as having emotional problems in the clinical range on the Strengths and Difficulties Questionnaire had significantly lower scores on the CEAS scales. The CEAS is a psychometrically sound instrument, covering healthy emotional adjustment as well as maladjustment. The scale might prove to be valuable in the assessment and screening of behaviours underlying child psychopathology. © 2014 John Wiley & Sons Ltd.
Distinguishing Between Convergent Evolution and Violation of the Molecular Clock for Three Taxa.
Mitchell, Jonathan D; Sumner, Jeremy G; Holland, Barbara R
2018-05-18
We give a non-technical introduction to convergence-divergence models, a new modeling approach for phylogenetic data that allows for the usual divergence of lineages after lineage-splitting but also allows for taxa to converge, i.e. become more similar over time. By examining the 3-taxon case in some detail we illustrate that phylogeneticists have been "spoiled" in the sense of not having to think about the structural parameters in their models by virtue of the strong assumption that evolution is tree-like. We show that there are not always good statistical reasons to prefer the usual class of tree-like models over more general convergence-divergence models. Specifically we show many 3-taxon data sets can be equally well explained by supposing violation of the molecular clock due to change in the rate of evolution along different edges, or by keeping the assumption of a constant rate of evolution but instead assuming that evolution is not a purely divergent process. Given the abundance of evidence that evolution is not strictly tree-like, our discussion is an illustration that as phylogeneticists we need to think clearly about the structural form of the models we use. For cases with four taxa we show that there will be far greater ability to distinguish models with convergence from non-clock-like tree models.
2013-01-01
Background Though several questionnaires on self-care and regimen adherence have been introduced, the evaluations do not always report consistent and substantial correlations with measures of glycaemic control. Small ability to explain variance in HbA1c constitutes a significant limitation of an instrument’s use for scientific purposes as well as clinical practice. In order to assess self-care activities which can predict glycaemic control, the Diabetes Self-Management Questionnaire (DSMQ) was designed. Methods A 16 item questionnaire to assess self-care activities associated with glycaemic control was developed, based on theoretical considerations and a process of empirical improvements. Four subscales, ‘Glucose Management’ (GM), ‘Dietary Control’ (DC), ‘Physical Activity’ (PA), and ‘Health-Care Use’ (HU), as well as a ‘Sum Scale’ (SS) as a global measure of self-care were derived. To evaluate its psychometric quality, 261 patients with type 1 or 2 diabetes were assessed with the DSMQ and an established analogous scale, the Summary of Diabetes Self-Care Activities Measure (SDSCA). The DSMQ’s item and scale characteristics as well as factorial and convergent validity were analysed, and its convergence with HbA1c was compared to the SDSCA. Results The items showed appropriate characteristics (mean item-total-correlation: 0.46 ± 0.12; mean correlation with HbA1c: -0.23 ± 0.09). Overall internal consistency (Cronbach’s alpha) was good (0.84), consistencies of the subscales were acceptable (GM: 0.77; DC: 0.77; PA: 0.76; HU: 0.60). Principal component analysis indicated a four factor structure and confirmed the designed scale structure. Confirmatory factor analysis indicated appropriate fit of the four factor model. The DSMQ scales showed significant convergent correlations with their parallel SDSCA scales (GM: 0.57; DC: 0.52; PA: 0.58; HU: n/a; SS: 0.57) and HbA1c (GM: -0.39; DC: -0.30; PA: -0.15; HU: -0.22; SS: -0.40). All correlations with HbA1c were significantly stronger than those obtained with the SDSCA. Conclusions This study provides preliminary evidence that the DSMQ is a reliable and valid instrument and enables an efficient assessment of self-care behaviours associated with glycaemic control. The questionnaire should be valuable for scientific analyses as well as clinical use in both type 1 and type 2 diabetes patients. PMID:23937988
Comparing photonic band structure calculation methods for diamond and pyrochlore crystals.
Vermolen, E C M; Thijssen, J H J; Moroz, A; Megens, M; van Blaaderen, A
2009-04-27
The photonic band diagrams of close-packed colloidal diamond and pyrochlore structures, have been studied using Korringa-Kohn-Rostoker (KKR) and plane-wave calculations. In addition, the occurrence of a band gap has been investigated for the binary Laves structures and their constituent large- and small-sphere substructures. It was recently shown that these Laves structures give the possibility to fabricate the diamond and pyrochlore structures by self-organization. The comparison of the two calculation methods opens the possibility to study the validity and the convergence of the results, which have been an issue for diamond-related structures in the past. The KKR calculations systematically give a lower value for the gap width than the plane-wave calculations. This difference can partly be ascribed to a convergence issue in the plane-wave code when a contact point of two spheres coincides with the grid.
Gomez, Rapson; Burns, G Leonard; Walsh, James A; Hafetz, Nina
2005-04-01
Confirmatory factor analysis (CFA) was used to model a multitrait by multisource matrix to determine the convergent and discriminant validity of measures of attention-deficit hyperactivity disorder (ADHD)-inattention (IN), ADHD-hyperactivity/impulsivity (HI), and oppositional defiant disorder (ODD) in 917 Malaysian elementary school children. The three trait factors were ADHD-IN, ADHDHI, and ODD. The two source factors were parents and teachers. Similar to earlier studies with Australian and Brazilian children, the parent and teacher measures failed to show convergent and discriminant validity with Malaysian children. The study outlines the implications of such strong source effects in ADHD-IN, ADHD-HI, and ODD measures for the use of such parent and teacher scales to study the symptom dimensions.
Steptoe, A; Pollard, T M; Wardle, J
1995-12-01
A number of factors are thought to influence people's dietary choices, including health, cost, convenience and taste, but there are no measures that address health-related and non-health-related factors in a systematic fashion. This paper describes the development of a multidimensional measure of motives related to food choice. The Food Choice Questionnaire (FCQ) was developed through factor analysis of responses from a sample of 358 adults ranging in age from 18 to 87 years. Nine factors emerged, and were labelled health, mood, convenience, sensory appeal, natural content, price, weight control, familiarity and ethical concern. The questionnaire structure was verified using confirmatory factor analysis in a second sample (n = 358), and test-retest reliability over a 2- to 3-week period was satisfactory. Convergent validity was investigated by testing associations between FCQ scales and measures of dietary restraint, eating style, the value of health, health locus of control and personality factors. Differences in motives for food choice associated with sex, age and income were found. The potential uses of this measure in health psychology and other areas are discussed.
Weak lensing probe of cubic Galileon model
NASA Astrophysics Data System (ADS)
Dinda, Bikash R.
2018-06-01
The cubic Galileon model containing the lowest non-trivial order action of the full Galileon action can produce the stable late-time cosmic acceleration. This model can have a significant role in the growth of structures. The signatures of the cubic Galileon model in the structure formation can be probed by the weak lensing statistics. Weak lensing convergence statistics is one of the strongest probes to the structure formation and hence it can probe the dark energy or modified theories of gravity models. In this work, we investigate the detectability of the cubic Galileon model from the ΛCDM model or from the canonical quintessence model through the convergence power spectrum and bi-spectrum.
Resizing procedure for optimum design of structures under combined mechanical and thermal loading
NASA Technical Reports Server (NTRS)
Adelman, H. M.; Narayanaswami, R.
1976-01-01
An algorithm is reported for resizing structures subjected to combined thermal and mechanical loading. The algorithm is applicable to uniaxial stress elements (rods) and membrane biaxial stress members. Thermal Fully Stressed Design (TFSD) is based on the basic difference between mechanical and thermal stresses in their response to resizing. The TFSD technique is found to converge in fewer iterations than ordinary fully stressed design for problems where thermal stresses are comparable to the mechanical stresses. The improved convergence is demonstrated by example with a study of a simplified wing structure, built-up with rods and membranes and subjected to a combination of mechanical loads and a three dimensional temperature distribution.
Neogene to recent contraction and basin inversion along the Nubia-Iberia boundary in SW Iberia
NASA Astrophysics Data System (ADS)
Ramos, Adrià; Fernández, Oscar; Terrinha, Pedro; Muñoz, Josep Anton
2017-02-01
The SW of Iberia is currently undergoing compression related to the convergence between Nubia and Iberia. Multiple compressive structures, and their related seismic activity, have been documented along the diffuse Nubia-Iberia plate boundary, including the Gorringe bank west of the Gulf of Cadiz, and the Betic-Rif orogen to the east. Despite seismic activity indicating a dominant compressive stress along the Algarve margin in the Gulf of Cadiz, the structures at the origin of this seismicity remain elusive. This paper documents the contractional structures that provide linkage across the Gulf of Cadiz and play a major role in defining the present-day seismicity and bathymetry of this area. The structures described in this paper caused the Neogene inversion of the Jurassic oblique passive margin that formed between the central Atlantic and the Ligurian Tethys. This example of a partially inverted margin provides insights into the factors that condition the inversion of passive margins.
Structure of the TRPA1 ion channel suggests regulatory mechanisms.
Paulsen, Candice E; Armache, Jean-Paul; Gao, Yuan; Cheng, Yifan; Julius, David
2015-04-23
The TRPA1 ion channel (also known as the wasabi receptor) is a detector of noxious chemical agents encountered in our environment or produced endogenously during tissue injury or drug metabolism. These include a broad class of electrophiles that activate the channel through covalent protein modification. TRPA1 antagonists hold potential for treating neurogenic inflammatory conditions provoked or exacerbated by irritant exposure. Despite compelling reasons to understand TRPA1 function, structural mechanisms underlying channel regulation remain obscure. Here we use single-particle electron cryo- microscopy to determine the structure of full-length human TRPA1 to ∼4 Å resolution in the presence of pharmacophores, including a potent antagonist. Several unexpected features are revealed, including an extensive coiled-coil assembly domain stabilized by polyphosphate co-factors and a highly integrated nexus that converges on an unpredicted transient receptor potential (TRP)-like allosteric domain. These findings provide new insights into the mechanisms of TRPA1 regulation, and establish a blueprint for structure-based design of analgesic and anti-inflammatory agents.
Structure of the TRPA1 ion channel suggests regulatory mechanisms
Paulsen, Candice E.; Armache, Jean-Paul; Gao, Yuan; Cheng, Yifan; Julius, David
2015-01-01
The TRPA1 ion channel (a.k.a the ‘wasabi receptor’) is a detector of noxious chemical agents encountered in our environment or produced endogenously during tissue injury or drug metabolism. These include a broad class of electrophiles that activate the channel through covalent protein modification. TRPA1 antagonists hold potential for treating neurogenic inflammatory conditions provoked or exacerbated by irritant exposure. Despite compelling reasons to understand TRPA1 function, structural mechanisms underlying channel regulation remain obscure. Here, we use single-particle electron cryo-microscopy to determine the structure of full-length human TRPA1 to ~4Å resolution in the presence of pharmacophores, including a potent antagonist. A number of unexpected features are revealed, including an extensive coiled-coil assembly domain stabilized by polyphosphate co-factors and a highly integrated nexus that converges on an unpredicted TRP-like allosteric domain. These findings provide novel insights into mechanisms of TRPA1 regulation, and establish a blueprint for structure-based design of analgesic and anti-inflammatory agents. PMID:25855297
Kanehara, Akiko; Kotake, Risa; Miyamoto, Yuki; Kumakura, Yousuke; Morita, Kentaro; Ishiura, Tomoko; Shimizu, Kimiko; Fujieda, Yumiko; Ando, Shuntaro; Kondo, Shinsuke; Kasai, Kiyoto
2017-11-07
Personal recovery is increasingly recognised as an important outcome measure in mental health services. This study aimed to develop a Japanese version of the Questionnaire about the Process of Recovery (QPR-J) and test its validity and reliability. The study comprised two stages that employed the cross-sectional and prospective cohort designs, respectively. We translated the questionnaire using a standard translation/back-translation method. Convergent validity was examined by calculating Pearson's correlation coefficients with scores on the Recovery Assessment Scale (RAS) and the Short-Form-8 Health Survey (SF-8). An exploratory factor analysis (EFA) was conducted to examine factorial validity. We used intraclass correlation and Cronbach's alpha to examine the test-retest and internal consistency reliability of the QPR-J's 22-item full scale, 17-item intrapersonal and 5-item interpersonal subscales. We conducted an EFA along with a confirmatory factor analysis (CFA). Data were obtained from 197 users of mental health services (mean age: 42.0 years; 61.9% female; 49.2% diagnosed with schizophrenia). The QPR-J showed adequate convergent validity, exhibiting significant, positive correlations with the RAS and SF-8 scores. The QPR-J's full version, subscales, showed excellent test-retest and internal consistency reliability, with the exception of acceptable but relatively low internal consistency reliability for the interpersonal subscale. Based on the results of the CFA and EFA, we adopted the factor structure extracted from the original 2-factor model based on the present CFA. The QPR-J is an adequately valid and reliable measure of the process of recovery among Japanese users with mental health services.
Pakpour, Amir H; Zeidi, Isa Mohammadi; Hashemi, Fariba; Saffari, Mohsen; Burri, Andrea
2013-01-01
The objective of the present study was to determine the reliability and validity of the Persian translation of the Pediatric Quality of Life Inventory (PedsQL™) 4.0 Generic Core Scales Young Adult Version in an Iranian sample of young adult patients with rheumatoid arthritis (RA). One hundred ninety-seven young adult patients with RA completed the 23-item PedsQL™ and the 36-item Short-Form Health Survey (SF-36). Disease activity based on Disease Activity Score 28 was also measured. Internal consistency and test-retest reliability, as well as construct, discriminant, and convergent validity, were tested. Confirmatory factor analysis (CFA) was used to verify the original factor structure of the PedsQL™. Also, responsiveness to change in PedsQL™ scores over time was assessed. Cronbach's alpha coefficients ranged from α = 0.82 to α = 0.91. Test-retest reproducibility was satisfactory for all scales and the total scale score. The PedsQL proved good convergent validity with the SF-36. The PedsQL distinguished well between young adult patients and healthy young adults and also RA groups with different comorbidities. The CFA did not confirm the original four-factor model, instead, analyses revealed a best-fitting five-factor model for the PedsQL™ Young Adult Version. Repeated measures analysis of variance indicated that the PedsQL scale scores for young adults increased significantly over time. The Persian translation of the PedsQL™ 4.0 Generic Core Scales Young Adult Version demonstrated good psychometric properties in young adult patients with RA and can be recommended for the use in RA research in Iran.
Ito, Masaya; Bentley, Kate H.; Oe, Yuki; Nakajima, Shun; Fujisato, Hiroko; Kato, Noriko; Miyamae, Mitsuhiro; Kanie, Ayako; Horikoshi, Masaru; Barlow, David H.
2015-01-01
Background The Overall Depression Severity and Impairment Scale (ODSIS) is a brief, five-item measure for assessing the frequency and intensity of depressive symptoms, as well as functional impairments in pleasurable activities, work or school, and interpersonal relationships due to depression. Although this scale is expected to be useful in various psychiatric and mental health settings, the reliability, validity, and interpretability have not yet been fully examined. This study was designed to examine the reliability, factorial, convergent, and discriminant validity of a Japanese version of the ODSIS, as well as its ability to distinguish between individuals with and without a major depressive disorder diagnosis. Methods From a pool of registrants at an internet survey company, 2830 non-clinical and clinical participants were selected randomly (619 with major depressive disorder, 619 with panic disorder, 576 with social anxiety disorder, 645 with obsessive–compulsive disorder, and 371 non-clinical panelists). Participants were asked to respond to the ODSIS and conventional measures of depression, functional impairment, anxiety, neuroticism, satisfaction with life, and emotion regulation. Results Exploratory and confirmatory factor analysis of three split subsamples indicated the unidimensional factor structure of ODSIS. Multi-group confirmatory factor analysis showed invariance of factor loadings between non-clinical and clinical subsamples. The ODSIS also showed excellent internal consistency and test–retest intraclass correlation coefficients. Convergence and discriminance of the ODSIS with various measures were in line with our expectations. Receiver operating characteristic curve analyses showed that the ODSIS was able to detect a major depressive syndrome accurately. Conclusions This study supports the reliability and validity of ODSIS in a non-western population, which can be interpreted as demonstrating cross-cultural validity. PMID:25874558
Bermúdez-de-Alvear, Rosa M; Gálvez-Ruiz, Pablo; Martínez-Arquero, A Ginés; Rando-Márquez, Sara; Fernández-Contreras, Elena
2018-06-11
This study aimed to analyze the psychometric properties of the Spanish version of the Voice Activity and Participation Profile (SVAPP) questionnaire. A randomized, cross-sectional sampling strategy with controls was used. Two samples with a total of 169 participants were analyzed, specifically 61 men (mean age 37.02) and 108 women (mean age 37.78). Of these participants, 112 were patients and 57 were controls. The instrument was submitted to reliability (internal consistency and corrected item-total correlations) and reproducibility analyses. Validation assessment was based on the construct validity, convergent validity, discriminant validity, and concurrent validity. The global internal consistency was excellent (Cronbach's α = 0.976), corrected item-total correlations were satisfactory and ranged 0.63-0.89, and factor loadings were above 0.50. The different subscales showed good internal consistency (alpha coefficients ranged 0.830-0.956) and test-retest values were consistently associated. The exploratory factor analysis evidenced a strongly defined five factors internal structure, with factors loadings ranging 0.51-0.86. Convergent validity demonstrated that all subscales and scores were very strongly correlated (Pearson r above 0.735) and significantly associated. The discriminant validity analysis showed that SVAPP had good specificity to distinguish dysphonic from healthy voice subjects. Concurrent validity with Voice Handicap Index Spanish version (SVHI) showed very strong correlations between total scores, and between SVHI total score and SVAPP Daily and Social Communication subscales; correlations between both tests subscales were strong; only between SVAPP Work and SVHI Physical sections correlations were moderate. The findings of the present study demonstrated evidence for the SVAPP questionnaire reliability and validity, and provided insightful implications of voice disorders on Spanish patients' quality of life. However, further investigations are required. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.
Discrete-Time Stable Generalized Self-Learning Optimal Control With Approximation Errors.
Wei, Qinglai; Li, Benkai; Song, Ruizhuo
2018-04-01
In this paper, a generalized policy iteration (GPI) algorithm with approximation errors is developed for solving infinite horizon optimal control problems for nonlinear systems. The developed stable GPI algorithm provides a general structure of discrete-time iterative adaptive dynamic programming algorithms, by which most of the discrete-time reinforcement learning algorithms can be described using the GPI structure. It is for the first time that approximation errors are explicitly considered in the GPI algorithm. The properties of the stable GPI algorithm with approximation errors are analyzed. The admissibility of the approximate iterative control law can be guaranteed if the approximation errors satisfy the admissibility criteria. The convergence of the developed algorithm is established, which shows that the iterative value function is convergent to a finite neighborhood of the optimal performance index function, if the approximate errors satisfy the convergence criterion. Finally, numerical examples and comparisons are presented.
NASA Astrophysics Data System (ADS)
Barnes, Philip M.; de Lépinay, Bernard Mercier
1997-11-01
Analysis of seismic reflection profiles, swath bathymetry, side-scan sonar imagery, and sediment samples reveal the three-dimensional structure, morphology, and stratigraphic evolution of the central to southern Hikurangi margin accretionary wedge, which is developing in response to thick trench fill sediment and oblique convergence between the Australian and Pacific plates. A seismic stratigraphy of the trench fill turbidites and frontal part of the wedge is constrained by seismic correlations to an already established stratigraphic succession nearby, by coccolith and foraminifera biostratigraphy of three core and dredge samples, and by estimates of stratigraphic thicknesses and rates of accumulation of compacted sediment. Structural and stratigraphic analyses of the frontal part of the wedge yield quantitative data on the timing of inception of thrust faults and folds, on the growth and mechanics of frontal accretion under variable convergence obliquity, and on the amounts and rates of horizontal shortening. The data place constraints on the partitioning of geological strain across the entire southern Hikurangi margin. The principal deformation front at the toe of the wedge is discontinuous and represented by right-stepping thrust faulted and folded ridges up to 1 km high, which develop initially from discontinuous protothrusts. In the central part of the margin near 41°S, where the convergence obliquity is 50°, orthogonal convergence rate is slow (27 mm/yr), and about 75% of the total 4 km of sediment on the Pacific Plate is accreted frontally, the seismically resolvable structures within 30 km of the deformation front accommodate about 6 km of horizontal shortening. At least 80% of this shortening has occurred within the last 0.4±0.1 m.y. at an average rate of 12±3 mm/yr. This rate indicates that the frontal 30 km of the wedge accounts for about 33-55% of the predicted orthogonal contraction across the entire plate boundary zone. Despite plate convergence obliquity of 50°, rapid frontal accretion has occurred during the late Quaternary with the principal deformation front migrating seaward up to 50 km within the last 0.5 m.y. (i.e., at a rate of 100 km/m.y.). The structural response to this accretion rate has been a reduction in wedge taper and, consequently, internal deformation behind the present deformation front. Near the southwestern termination of the wedge, where there is an along-the-margin transition to continental transpressional tectonics, the convergence obliquity increases to >56°, and the orthogonal convergence rate decreases to 22 mm/yr, the wedge narrows to 13 km and is characterized simply by two frontal backthrusts and landward-verging folds. These structures have accommodated not more than 0.5 km of horizontal shortening at a rate of < 1 mm/yr, which represents < 5% of the predicted orthogonal shortening across the entire plate boundary in southern North Island. The landward-vergent structural domain may represent a transition zone from rapid frontal accretion associated with low basal friction and high pore pressure ratio in the central part of the margin, to the northern South Island region where the upper and lower plates are locked or at least very strongly coupled.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi, Sunghwan; Hong, Kwangwoo; Kim, Jaewook
2015-03-07
We developed a self-consistent field program based on Kohn-Sham density functional theory using Lagrange-sinc functions as a basis set and examined its numerical accuracy for atoms and molecules through comparison with the results of Gaussian basis sets. The result of the Kohn-Sham inversion formula from the Lagrange-sinc basis set manifests that the pseudopotential method is essential for cost-effective calculations. The Lagrange-sinc basis set shows faster convergence of the kinetic and correlation energies of benzene as its size increases than the finite difference method does, though both share the same uniform grid. Using a scaling factor smaller than or equal tomore » 0.226 bohr and pseudopotentials with nonlinear core correction, its accuracy for the atomization energies of the G2-1 set is comparable to all-electron complete basis set limits (mean absolute deviation ≤1 kcal/mol). The same basis set also shows small mean absolute deviations in the ionization energies, electron affinities, and static polarizabilities of atoms in the G2-1 set. In particular, the Lagrange-sinc basis set shows high accuracy with rapid convergence in describing density or orbital changes by an external electric field. Moreover, the Lagrange-sinc basis set can readily improve its accuracy toward a complete basis set limit by simply decreasing the scaling factor regardless of systems.« less
Predicting delinquency by self-reported impulsivity in adolescents in Ghana.
Adjorlolo, Samuel; Asamoah, Edward; Adu-Poku, Sarah
2018-06-01
Impulsivity is one of several variables associated with delinquent and criminal acts, but its utility depends on the psychometric properties of the measure used. To investigate the latent structure of the abbreviated Barratt Impulsivity Scale (ABIS) and its convergent validity with measures of aggression and psychopathy in a Ghanaian sample. In a cross-sectional survey, high school students were recruited from two randomly selected schools in Ghana and asked to respond to the ABIS and measures of delinquency, aggression and psychopathy. Three hundred and sixty-three young people, aged 15-19 were recruited, 149 (41%) boys. Findings supported a three-factor (attention, motor and non-planning) structure of impulsivity, which did not differ by sex. Motor and attentional impulsivity were associated with both violent and general delinquent behaviours. Impulsivity scores also correlated with aggression and psychopathy scores, thus providing evidence of convergent validity. The ABIS was shown to have sound psychometrics in a standard Ghanaian secondary school sample. Even in this group, where delinquency and antisocial behaviours were of low frequency, its motor and attention impulsivity scores were shown to have some relationship with violent and general delinquent behaviours, suggesting that the ABIS could be a useful tool across cultures for identifying adolescents at high risk of such problems and intervening early to limit damage. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
The Work-Health-Check (WHC): a brief new tool for assessing psychosocial stress in the workplace.
Gadinger, M C; Schilling, O; Litaker, D; Fischer, J E
2012-01-01
Brief, psychometrically robust questionnaires assessing work-related psychosocial stressors are lacking. The purpose of the study is to evaluate the psychometric properties of a brief new questionnaire for assessing sources of work-related psychosocial stress. Managers, blue- and white-collar workers (n= 628 at measurement point one, n=459 at measurement point two), sampled from an online panel of a German marketing research institute. We either developed or identified appropriate items from existing questionnaires for ten scales, which are conceptually based in work stress models and reflected either work-related demands or resources. Factorial structure was evaluated by confirmatory factor analyses (CFA). Scale reliability was assessed by Cronbach's Alpha, and test-retest; correlations with work-related efforts demonstrated convergent and discriminant validity for the demand and resource scales, respectively. Scale correlations with health indicators tested criterion validity. All scales had satisfactory reliability (Cronbach's Alpha: 0.74-0.93, retest reliabilities: 0.66-0.81). CFA supported the anticipated factorial structure. Significant correlations between job-related efforts and demand scales (mean r=0.44) and non-significant correlations with the resource scales (mean r=0.07) suggested good convergent and discriminant validity, respectively. Scale correlations with health indicators demonstrated good criterion validity. The WHC appears to be a brief, psychometrically robust instrument for assessing work-related psychosocial stressors.
Convergence in parameters and predictions using computational experimental design.
Hagen, David R; White, Jacob K; Tidor, Bruce
2013-08-06
Typically, biological models fitted to experimental data suffer from significant parameter uncertainty, which can lead to inaccurate or uncertain predictions. One school of thought holds that accurate estimation of the true parameters of a biological system is inherently problematic. Recent work, however, suggests that optimal experimental design techniques can select sets of experiments whose members probe complementary aspects of a biochemical network that together can account for its full behaviour. Here, we implemented an experimental design approach for selecting sets of experiments that constrain parameter uncertainty. We demonstrated with a model of the epidermal growth factor-nerve growth factor pathway that, after synthetically performing a handful of optimal experiments, the uncertainty in all 48 parameters converged below 10 per cent. Furthermore, the fitted parameters converged to their true values with a small error consistent with the residual uncertainty. When untested experimental conditions were simulated with the fitted models, the predicted species concentrations converged to their true values with errors that were consistent with the residual uncertainty. This paper suggests that accurate parameter estimation is achievable with complementary experiments specifically designed for the task, and that the resulting parametrized models are capable of accurate predictions.
Cross-cultural validation of the Resilience Scale for Adults (RSA) in Iran.
Jowkar, Bahram; Friborg, Oddgeir; Hjemdal, Odin
2010-10-01
Resilience, as an ability to withstand and rebound from crisis and adversity, is becoming an increasingly popular concept in research on intervention and prevention of mental health. The present study examined psychometric properties of a Persian version of the Resilience Scale for Adults (RSA), a scale intended to measure protective factors presumed to enhance resilience. The participants were 373 university undergraduate students, as well as 30 pairs of run-away girls and a matched control group. A confirmatory factor analysis verified the Norwegian five-factor structure. All subscale scores, personal competence, social competence, family cohesion, social resources and structured style, had good reliability. The convergent validity of the RSA was supported by showing positive associations with another resilience scale, i.e., a Persian version of the Connor-Davidson Resilience Scale (CD-RISC). Predictive validity of the RSA was supported, as well, by significantly differentiating between girls who had run away from home and a matched control group. The results indicate that the RSA may be a valid and reliable scale for the assessment of resilience protective resources in an Iranian population. © 2010 The Authors. Scandinavian Journal of Psychology © 2010 The Scandinavian Psychological Associations.
Social Skills Questionnaire for Argentinean College Students (SSQ-U) Development and Validation.
Morán, Valeria E; Olaz, Fabián O; Del Prette, Zilda A P
2015-11-27
In this paper we present a new instrument called Social Skills Questionnaire for Argentinean College Students (SSQ-U). Based on the adapted version of the Social Skills Inventory - Del Prette (SSI-Del Prette) (Olaz, Medrano, Greco, & Del Prette, 2009), we wrote new items for the scale, and carried out psychometric analysis to assess the validity and reliability of the instrument. In the first study, we collected evidence based on test content through expert judges who evaluated the quality and the relevance of the items. In the second and third studies, we provided validity evidence based on the internal structure of the instrument using exploratory (n = 1067) and confirmatory (n = 661) factor analysis. Results suggested a five-factor structure consistent with the dimensions of social skills, as proposed by Kelly (2002). The fit indexes corresponding to the obtained model were adequate, and composite reliability coefficients of each factor were excellent (above .75). Finally, in the fourth study, we provided evidence of convergent and discriminant validity. The obtained results allow us to conclude that the SSQ-U is the first valid and reliable instrument for measuring social skills in Argentinean college students.
Pakpour, Amir H; Zeidi, Isa Mohammadi; Ziaeiha, Masoumeh; Burri, Andrea
2014-01-01
The aim of the present study was to investigate the psychometric properties of a translated and culturally adapted Iranian version of the Female Genital Self-Image Scale (FGSIS-I) in a sample of college women. Further, the relationship between women's self-image, body appreciation, sexual functioning, and gynecological exam behavior was explored. A sample of 1,877 female students from five different universities across Qazvin and Tehran completed the Female Sexual Function Index (FSFI), the Body Appreciation Scale (BAS), the Rosenberg Self-Esteem Scale (RSES), the FGSIS-I, and a gynecological exam behavior questionnaire. Good to excellent internal consistency reliability, test-retest reliability, and convergent and construct validity were found. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) both provided a two-factor structure for the FGSIS-I. The validity of the FGSIS-I in predicting gynecological exam behavior of college women was tested using structural equation modeling (SEM). The final model accounted for 33% of the variance in gynecological exam behavior (p < 0.01). In conclusion, the FGSIS-I was found to be a highly valid and reliable instrument to assess female genital self-image in Iranian women.
Structure of the nucleotide exchange factor eIF2B reveals mechanism of memory-enhancing molecule.
Tsai, Jordan C; Miller-Vedam, Lakshmi E; Anand, Aditya A; Jaishankar, Priyadarshini; Nguyen, Henry C; Renslo, Adam R; Frost, Adam; Walter, Peter
2018-03-30
Regulation by the integrated stress response (ISR) converges on the phosphorylation of translation initiation factor eIF2 in response to a variety of stresses. Phosphorylation converts eIF2 from a substrate to a competitive inhibitor of its dedicated guanine nucleotide exchange factor, eIF2B, thereby inhibiting translation. ISRIB, a drug-like eIF2B activator, reverses the effects of eIF2 phosphorylation, and in rodents it enhances cognition and corrects cognitive deficits after brain injury. To determine its mechanism of action, we solved an atomic-resolution structure of ISRIB bound in a deep cleft within decameric human eIF2B by cryo-electron microscopy. Formation of fully active, decameric eIF2B holoenzyme depended on the assembly of two identical tetrameric subcomplexes, and ISRIB promoted this step by cross-bridging a central symmetry interface. Thus, regulation of eIF2B assembly emerges as a rheostat for eIF2B activity that tunes translation during the ISR and that can be further modulated by ISRIB. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Measuring romantic love: psychometric properties of the infatuation and attachment scales.
Langeslag, Sandra J E; Muris, Peter; Franken, Ingmar H A
2013-01-01
Romantic love is ubiquitous and has major influences on people's lives. Because romantic love consists of infatuation and attachment, researchers need to be able to differentiate between these constructs when examining the behavioral, affective, cognitive, and physiological correlates of this intriguing phenomenon. Existing love questionnaires appear less suitable for measuring the two-dimensional construct of romantic love. We present here the new 20-item Infatuation and Attachment Scales (IAS) questionnaire. In Study 1, exploratory factor analyses in a Dutch-speaking sample (n = 162) revealed a clear-cut two-factor structure, with 10 infatuation and 10 attachment items loading on separate components. This two-factor structure was confirmed in a new Dutch-speaking sample (n = 214, Study 2), and in an English-speaking sample (n = 183, Study 3). In all studies, it was additionally shown that both scales possessed good convergent and discriminant validity, as well as excellent internal consistency and test-retest reliability. We argue that the IAS is a widely applicable, psychometrically sound instrument that will be useful in future research exploring the effects of infatuation and attachment on behavior, emotion, cognition, peripheral physiology, and brain functioning.
Cheng, Li; Leung, Doris Y P; Wu, Yu-Ning; Sit, Janet W H; Yang, Miao-Yan; Li, Xiao-Mei
2018-03-01
This study examined the psychometric properties of the Chinese version of the Personal Diabetes Questionnaire (C-PDQ). The PDQ was translated into Chinese using a forward and backward translation approach. After being reviewed by an expert panel, the C-PDQ was administered to a convenience sample of 346 adults with Type 2 diabetes. The Chinese version of the Summary of Diabetes Self-Care Activities (C-SDSCA) was also administered. The results of the exploratory factor analysis revealed a one-factor structure for the Diet Knowledge, Decision-Making, and Eating Problems subscales and a two-factor structure for the barriers-related subscales. The criterion and convergent validity were supported by significant correlations of the subscales of the C-PDQ with the glycated hemoglobin values and the parallel subscales in the C-SDSCA, respectively. The C-PDQ subscales also showed acceptable internal consistency (α = .61-.89) and excellent test-retest reliability (intraclass correlation coefficients: .73-.96). The results provide preliminary support for the reliability and validity of the C-PDQ. This comprehensive, patient-centered instrument could be useful to identify the needs, concerns, and priorities of Chinese patients with type 2 diabetes.
Policy Gradient Adaptive Dynamic Programming for Data-Based Optimal Control.
Luo, Biao; Liu, Derong; Wu, Huai-Ning; Wang, Ding; Lewis, Frank L
2017-10-01
The model-free optimal control problem of general discrete-time nonlinear systems is considered in this paper, and a data-based policy gradient adaptive dynamic programming (PGADP) algorithm is developed to design an adaptive optimal controller method. By using offline and online data rather than the mathematical system model, the PGADP algorithm improves control policy with a gradient descent scheme. The convergence of the PGADP algorithm is proved by demonstrating that the constructed Q -function sequence converges to the optimal Q -function. Based on the PGADP algorithm, the adaptive control method is developed with an actor-critic structure and the method of weighted residuals. Its convergence properties are analyzed, where the approximate Q -function converges to its optimum. Computer simulation results demonstrate the effectiveness of the PGADP-based adaptive control method.
Communication failure: basic components, contributing factors, and the call for structure.
Dayton, Elizabeth; Henriksen, Kerm
2007-01-01
Communication is a taken-for-granted human activity that is recognized as important once it has failed. Communication failures are a major contributor to adverse events in health care. The components and processes of communication converge in an intricate manner, creating opportunities for misunderstanding along the way. When a patient's safety is at risk, providers should speak up (that is, initiate a message) to draw attention to the situation before harm is caused. They should also clearly explain (encode) and understand (decode) each other's diagnosis and recommendations to ensure well coordinated delivery of care. Beyond basic dyadic communication exchanges, an intricate web of individual, group, and organizational factors--more specifically, cognitive workload, implicit assumptions, authority gradients, diffusion of responsibility, and transitions of care--complicate communication. More structured and explicitly designed forms of communication have been recommended to reduce ambiguity, enhance clarity, and send an unequivocal signal, when needed, that a different action is required. Read-backs, Situation-Background-Assessment-Recommendation, critical assertions, briefings, and debriefings are seeing increasing use in health care. CODA: Although structured forms of communication have good potential to enhance clarity, they are not fail-safe. Providers need to be sensitive to unexpected consequences regarding their use.
Garcia, Antonio F.; Acosta, Melina; Pirani, Saifa; Edwards, Daniel; Osman, Augustine
2017-01-01
We describe 2 studies designed to evaluate scores on the Multidimensional Shame-related Response Inventory-21 (MSRI-21), a recently developed instrument that measures affective and behavioral responses to shame. The inventory assesses shame-related responses in 3 categories: negative self-evaluation, fear of social consequences, and maladaptive behavior tendency. For Study 1, (N = 743) undergraduates completed the MSRI-21. Confirmatory factor analysis supported the validity of the MSRI-21 3-factor structure. Latent variable modeling of coefficient-α provided strong evidence for the internal consistency of scores on each scale. In Study 2, (N = 540) undergraduates completed the instrument along with 5 concurrent measures chosen for clinical significance. Achievement of factorial invariance supported the use of MSRI-21 scale scores to make valid mean comparisons across gender. In addition, MSRI-21 scale scores were associated as expected with scores on measures of self-harm, suicide, and other risk factors. Taken together, results of 2 studies support the internal consistency reliability, factorial validity, factorial invariance, and convergent validity of scores on the MSRI-21. Further work is needed to assess the temporal stability of the MSRI-21 scale scores, invariance across clinical status and other groupings, item-level measurement properties, and viability in highly symptomatic samples. PMID:28182490
Martínez-González, Agustín E.; Rodríguez-Jiménez, Tíscar; Piqueras, José A.; Vera-Villarroel, Pablo; Godoy, Antonio
2015-01-01
In recent years, there has been a considerable increase in the development of assessment tools for obsessive-compulsive symptomatology in children and adolescents. The Obsessive Compulsive Inventory-Child Version (OCI-CV) is a well-established assessment self-report, with special interest for the assessment of dimensions of Obsessive Compulsive Disorder (OCD). This instrument has shown to be useful for clinical and non-clinical populations in two languages (English and European Spanish). Thus, the aim of this study was to analyze the psychometric properties of the OCI-CV in a Chilean community sample. The sample consisted of 816 children and adolescents with a mean age of 14.54 years (SD = 2.21; range = 10–18 years). Factor structure, internal consistency, test-retest reliability, convergent/divergent validity, and gender/age differences were examined. Confirmatory factor analysis showed a 6-factor structure (Doubting/Checking, Obsessing, Hoarding, Washing, Ordering, and Neutralizing) with one second-order factor. Good estimates of reliability (including internal consistency and test-retest), evidence supporting the validity, and small age and gender differences (higher levels of OCD symptomatology among older participants and women, respectively) are found. The OCI-CV is also an adequate scale for the assessment of obsessions and compulsions in a general population of Chilean children and adolescents. PMID:26317404
Communication: Finite size correction in periodic coupled cluster theory calculations of solids.
Liao, Ke; Grüneis, Andreas
2016-10-14
We present a method to correct for finite size errors in coupled cluster theory calculations of solids. The outlined technique shares similarities with electronic structure factor interpolation methods used in quantum Monte Carlo calculations. However, our approach does not require the calculation of density matrices. Furthermore we show that the proposed finite size corrections achieve chemical accuracy in the convergence of second-order Møller-Plesset perturbation and coupled cluster singles and doubles correlation energies per atom for insulating solids with two atomic unit cells using 2 × 2 × 2 and 3 × 3 × 3 k-point meshes only.
The punctilious RNA polymerase II core promoter
Vo ngoc, Long; Wang, Yuan-Liang; Kassavetis, George A.; Kadonaga, James T.
2017-01-01
The signals that direct the initiation of transcription ultimately converge at the core promoter, which is the gateway to transcription. Here we provide an overview of the RNA polymerase II core promoter in bilateria (bilaterally symmetric animals). The core promoter is diverse in terms of its composition and function yet is also punctilious, as it acts with strict rules and precision. We additionally describe an expanded view of the core promoter that comprises the classical DNA sequence motifs, sequence-specific DNA-binding transcription factors, chromatin signals, and DNA structure. This model may eventually lead to a more unified conceptual understanding of the core promoter. PMID:28808065