Differences in within- and between-person factor structure of positive and negative affect: analysis of two intensive measurement studies using multilevel structural equation modeling.

PubMed

Rush, Jonathan; Hofer, Scott M

2014-06-01

The Positive and Negative Affect Schedule (PANAS) is a widely used measure of emotional experience. The factor structure of the PANAS has been examined predominantly with cross-sectional designs, which fails to disaggregate within-person variation from between-person differences. There is still uncertainty as to the factor structure of positive and negative affect and whether they constitute 2 distinct independent factors. The present study examined the within-person and between-person factor structure of the PANAS in 2 independent samples that reported daily affect over 7 and 14 occasions, respectively. Results from multilevel confirmatory factor analyses revealed that a 2-factor structure at both the within-person and between-person levels, with correlated specific factors for overlapping items, provided good model fit. The best-fitting solution was one where within-person factors of positive and negative affect were inversely correlated, but between-person factors were independent. The structure was further validated through multilevel structural equation modeling examining the effects of cognitive interference, daily stress, physical symptoms, and physical activity on positive and negative affect factors.

Factor Structure of the Brief Symptom Inventory--18 in Adult Survivors of Childhood Cancer: Results from the Childhood Cancer Survivor Study

ERIC Educational Resources Information Center

Recklitis, Christopher J.; Parsons, Susan K.; Shih, Mei-Chiung; Mertens, Ann; Robison, Leslie L.; Zeltzer, Lonnie

2006-01-01

The factor structure of the Brief Symptom Inventory--18 (BSI-18; L. R. Derogatis, 2000) was investigated in a sample of adult survivors of childhood cancer enrolled in the Childhood Cancer Survivor Study (CCSS; N = 8,945). An exploratory factor analysis with a randomly chosen subsample supported a 3-factor structure closely corresponding to the 3…

Factor Structure and Psychometric Properties of the Injection Phobia Scale-Anxiety

ERIC Educational Resources Information Center

Olatunji, Bunmi O.; Sawchuk, Craig N.; Moretz, Melanie W.; David, Bieke; Armstrong, Thomas; Ciesielski, Bethany G.

2010-01-01

The present investigation examined the factor structure and psychometric properties of the Injection Phobia Scale-Anxiety (IPS-Anx). Principal components analysis of IPS-Anx items in Study 1 (n = 498) revealed a 2-factor structure consisting of Distal Fear and Contact Fear. However, CFA results in Study 2 (n = 567) suggest that a 1-factor…

[Volunteer satisfaction: Internal structure and relationship with permanence in organizations].

PubMed

Vecina Jiménez, M L; Chacón Fuertes, Fernando; Sueiro Abad, Manuel J

2009-02-01

Volunteer satisfaction: Internal structure and relationship with permanence in organizations. The concept of satisfaction is considered theoretically relevant in practically all the studies that have investigated the factors that influence the permanence of volunteer participation in organizations. However, the practical results are not conclusive, perhaps due to the wide range of ways in which the concept is understood and measured. The object of this study is: to analyse the internal structure of satisfaction and to verify its relationship with volunteer duration in organizations. The results of the factor analysis yield a three-factor structure: Satisfaction with the management of the organization, Satisfaction with the tasks, Satisfaction of motivations. The three factors allow us to differentiate between individuals who remain in the organization for a period of 12 consecutive months, and those who leave earlier. The results of structural equation model analysis show that the relationship between satisfaction and the length of time that volunteers stay with the organization is affected by the intention to remain.

Factor structure and psychometric properties of the Body Appreciation Scale among adults in Hong Kong.

PubMed

Ng, Siu-Kuen; Barron, David; Swami, Viren

2015-03-01

Previous research has suggested that the factor structure of Body Appreciation Scale (BAS), a widely-used measure of positive body image, may not be cross-culturally equivalent. Here, we used confirmatory factor analysis to evaluate the conceptual equivalence of a Chinese (Cantonese) translation of the BAS among women (n=1319) and men (n=1084) in Hong Kong. Results showed that neither the one-dimensional nor proposed two-dimensional factor structures had adequate fit. Instead, a modified two-dimensional structure, which retained 9 of the 13 BAS items in two factors, had the best fit. However, only one of these factors, reflective of General Body Appreciation, had adequate internal consistency. This factor also had good patterns of construct validity, as indicated through significant correlations with participant body mass index, self-esteem, and (among women) actual-ideal weight discrepancy. The present results suggest that there may be cultural differences in the concept and experience of body appreciation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Investigation of structural factors of safety for the space shuttle

NASA Technical Reports Server (NTRS)

1972-01-01

A study was made of the factors governing the structural design of the fully reusable space shuttle booster to establish a rational approach to select optimum structural factors of safety. The study included trade studies of structural factors of safety versus booster service life, weight, cost, and reliability. Similar trade studies can be made on other vehicles using the procedures developed. The major structural components of a selected baseline booster were studied in depth, each being examined to determine the fatigue life, safe-life, and fail-safe capabilities of the baseline design. Each component was further examined to determine its reliability and safety requirements, and the change of structural weight with factors of safety. The apparent factors of safety resulting from fatigue, safe-life, proof test, and fail-safe requirements were identified. The feasibility of reduced factors of safety for design loads such as engine thrust, which are well defined, was examined.

Factor Structure and Psychometric Properties of the Brief Illness Perception Questionnaire in Turkish Cancer Patients

PubMed Central

Karataş, Tuğba; Özen, Şükrü; Kutlutürkan, Sevinç

2017-01-01

Objective: The main aim of this study was to investigate the factor structure and psychometric properties of the Brief Illness Perception Questionnaire (BIPQ) in Turkish cancer patients. Methods: This methodological study involved 135 cancer patients. Statistical methods included confirmatory or exploratory factor analysis and Cronbach alpha coefficients for internal consistency. Results: The values of fit indices are within the acceptable range. The alpha coefficients for emotional illness representations, cognitive illness representations, and total scale are 0.83, 0.80, and 0.85, respectively. Conclusions: The results confirm the two-factor structure of the Turkish BIPQ and demonstrate its reliability and validity. PMID:28217734

The School Counselor Leadership Survey: Instrument Development and Exploratory Factor Analysis

ERIC Educational Resources Information Center

Young, Anita; Bryan, Julia

2015-01-01

This study examined the factor structure of the School Counselor Leadership Survey (SCLS). Survey development was a threefold process that resulted in a 39-item survey of 801 school counselors and school counselor supervisors. The exploratory factor analysis indicated a five-factor structure that revealed five key dimensions of school counselor…

Evaluating the Factor Validity of the Children's Organizational Skills Scale in Youth with ADHD.

PubMed

Molitor, Stephen J; Langberg, Joshua M; Evans, Steven W; Dvorsky, Melissa R; Bourchtein, Elizaveta; Eddy, Laura D; Smith, Zoe R; Oddo, Lauren E

2017-06-01

Children and adolescents with ADHD often have difficulties with organization, time management, and planning (OTMP) skills, and these skills are a common target of intervention. A limited array of tools for measuring these abilities in youth is available, and one of the most prominent measures is the Children's Organizational Skills Scale (COSS). Although the COSS fills an important need, a replication of the COSS factor structure outside of initial measure development has not been conducted in any population. Given that the COSS is frequently used in ADHD research, the current study evaluated the factor structure of the parent-rated COSS in a sample ( N = 619) of adolescents with ADHD. Results indicated that the original factor structure could be replicated, although the use of item parcels appeared to affect model fit statistics. An alternative bi-factor model was also tested that did not require the use of parcels, with results suggesting similar model fit in comparison to the original factor structure. Exploratory validity tests indicated that the domain-general factor of the bi-factor model appears related to broad executive functioning abilities.

Assessing a dysphoric arousal model of acute stress disorder symptoms in a clinical sample of rape and bank robbery victims

PubMed Central

Hansen, Maj; Armour, Cherie; Elklit, Ask

2012-01-01

Background Since the introduction of Acute Stress Disorder (ASD) into the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) research has focused on the ability of ASD to predict PTSD rather than focusing on addressing ASD's underlying latent structure. The few existing confirmatory factor analytic (CFA) studies of ASD have failed to reach a clear consensus regarding ASD's underlying dimensionality. Although, the discrepancy in the results may be due to varying ASD prevalence rates, it remains possible that the model capturing the latent structure of ASD has not yet been put forward. One such model may be a replication of a new five-factor model of PTSD, which separates the arousal symptom cluster into Dysphoric and Anxious Arousal. Given the pending DSM-5, uncovering ASD's latent structure is more pertinent than ever. Objective Using CFA, four different models of the latent structure of ASD were specified and tested: the proposed DSM-5 model, the DSM-IV model, a three factor model, and a five factor model separating the arousal symptom cluster. Method The analyses were based on a combined sample of rape and bank robbery victims, who all met the diagnostic criteria for ASD (N = 404) using the Acute Stress Disorder Scale. Results The results showed that the five factor model provided the best fit to the data. Conclusions The results of the present study suggest that the dimensionality of ASD may be best characterized as a five factor structure which separates dysphoric and anxious arousal items into two separate factors, akin to recent research on PTSD's latent structure. Thus, the current study adds to the debate about how ASD should be conceptualized in the pending DSM-5. PMID:22893845

Psychometric properties of the Internet Addiction Test in Turkish

PubMed Central

Kaya, Fatih; Delen, Erhan; Young, Kimberly S.

2016-01-01

Background and aims In this study, the Internet Addiction Test (IAT) was adapted to Turkish language, which was originally developed by Young (1998) in English to measure the presence and severity of the Internet dependency. The main purpose was to ensure that the psychometric features and the factor structure of the test were suitable for Turkish university students. Method The study was conducted in two sequent phases. Participants were 990 undergraduate students from several public universities in Turkey. Results In the first phase, an exploratory factor analysis (EFA) was applied to figure out the factor structure of the Turkish version of the IAT. The EFA revealed four factors, which explained 46.02% of the total variance. In the following phase, a confirmatory factor analysis (CFA) was conducted with a different sample, to verify the factor structure that was found in the initial EFA. The CFA resulted four-factor model was satisfactory for the Turkish version of the IAT. These four factors were named as Mood, Relationship, Responsibilities, and Duration. Conclusions Based on the findings, the administration of Turkish version of the IAT provided acceptable results on undergraduate students. PMID:28092191

Recovery of Weak Factor Loadings When Adding the Mean Structure in Confirmatory Factor Analysis: A Simulation Study

PubMed Central

Ximénez, Carmen

2016-01-01

This article extends previous research on the recovery of weak factor loadings in confirmatory factor analysis (CFA) by exploring the effects of adding the mean structure. This issue has not been examined in previous research. This study is based on the framework of Yung and Bentler (1999) and aims to examine the conditions that affect the recovery of weak factor loadings when the model includes the mean structure, compared to analyzing the covariance structure alone. A simulation study was conducted in which several constraints were defined for one-, two-, and three-factor models. Results show that adding the mean structure improves the recovery of weak factor loadings and reduces the asymptotic variances for the factor loadings, particularly for the models with a smaller number of factors and a small sample size. Therefore, under certain circumstances, modeling the means should be seriously considered for covariance models containing weak factor loadings. PMID:26779071

Factor structure and psychometric properties of the trier inventory for chronic stress (TICS) in a representative german sample

PubMed Central

2012-01-01

Background Chronic stress results from an imbalance of personal traits, resources and the demands placed upon an individual by social and occupational situations. This chronic stress can be measured using the Trier Inventory for Chronic Stress (TICS). Aims of the present study are to test the factorial structure of the TICS, report its psychometric properties, and evaluate the influence of gender and age on chronic stress. Methods The TICS was answered by N = 2,339 healthy participants aged 14 to 99. The sample was selected by random-route sampling. Exploratory factor analyses with Oblimin-rotated Principal Axis extraction were calculated. Confirmatory factor analyses applying Robust Maximum Likelihood estimations (MLM) tested model fit and configural invariance as well as the measurement invariance for gender and age. Reliability estimations and effect sizes are reported. Results In the exploratory factor analyses, both a two-factor and a nine-factor model emerged. Confirmatory factor analyses resulted in acceptable model fit (RMSEA), with model comparison fit statistics corroborating the superiority of the nine-factor model. Most factors were moderately to highly intercorrelated. Reliabilities were good to very good. Measurement invariance tests gave evidence for differential effects of gender and age on the factor structure. Furthermore, women and younger individuals, especially those aged 35 to 44, tended to report more chronic stress than men and older individuals. Conclusions The proposed nine-factor structure could be factorially validated, results in good scale reliability, and heuristically can be grouped by two higher-order factors: "High Demands" and "Lack of Satisfaction". Age and gender represent differentiable and meaningful contributors to the perception of chronic stress. PMID:22463771

Confirmatory factor analysis of the Child Oral Health Impact Profile (Korean version).

PubMed

Cho, Young Il; Lee, Soonmook; Patton, Lauren L; Kim, Hae-Young

2016-04-01

Empirical support for the factor structure of the Child Oral Health Impact Profile (COHIP) has not been fully established. The purposes of this study were to evaluate the factor structure of the Korean version of the COHIP (COHIP-K) empirically using confirmatory factor analysis (CFA) based on the theoretical framework and then to assess whether any of the factors in the structure could be grouped into a simpler single second-order factor. Data were collected through self-reported COHIP-K responses from a representative community sample of 2,236 Korean children, 8-15 yr of age. Because a large inter-factor correlation of 0.92 was estimated in the original five-factor structure, the two strongly correlated factors were combined into one factor, resulting in a four-factor structure. The revised four-factor model showed a reasonable fit with appropriate inter-factor correlations. Additionally, the second-order model with four sub-factors was reasonable with sufficient fit and showed equal fit to the revised four-factor model. A cross-validation procedure confirmed the appropriateness of the findings. Our analysis empirically supported a four-factor structure of COHIP-K, a summarized second-order model, and the use of an integrated summary COHIP score. © 2016 Eur J Oral Sci.

The relationship between community structural characteristics, the context of crack use and HIV risk behaviors in San Salvador, El Salvador1

PubMed Central

Dickson-Gomez, Julia; McAuliffe, Timothy; de Mendoza, Lorena Rivas; Glasman, Laura; Gaborit, Mauricio

2012-01-01

This paper explores community structural factors in different low-income communities in the San Salvador, El Salvador that account for differences in the social context in which crack is used and in the HIV risk behaviors among crack users. Results suggest that both more distal (type of low-income community, level of violent crime and poverty) and proximate structural factors (type of site where drugs are used, and whether drugs are used within or outside of community of residence) influence HIV risk behaviors among drug users. Additionally, our results suggest that community structural factors influence the historical and geographic variation in drug use sites. PMID:22217125

Evaluating WAIS-IV structure through a different psychometric lens: structural causal model discovery as an alternative to confirmatory factor analysis.

PubMed

van Dijk, Marjolein J A M; Claassen, Tom; Suwartono, Christiany; van der Veld, William M; van der Heijden, Paul T; Hendriks, Marc P H

Since the publication of the WAIS-IV in the U.S. in 2008, efforts have been made to explore the structural validity by applying factor analysis to various samples. This study aims to achieve a more fine-grained understanding of the structure of the Dutch language version of the WAIS-IV (WAIS-IV-NL) by applying an alternative analysis based on causal modeling in addition to confirmatory factor analysis (CFA). The Bayesian Constraint-based Causal Discovery (BCCD) algorithm learns underlying network structures directly from data and assesses more complex structures than is possible with factor analysis. WAIS-IV-NL profiles of two clinical samples of 202 patients (i.e. patients with temporal lobe epilepsy and a mixed psychiatric outpatient group) were analyzed and contrasted with a matched control group (N = 202) selected from the Dutch standardization sample of the WAIS-IV-NL to investigate internal structure by means of CFA and BCCD. With CFA, the four-factor structure as proposed by Wechsler demonstrates acceptable fit in all three subsamples. However, BCCD revealed three consistent clusters (verbal comprehension, visual processing, and processing speed) in all three subsamples. The combination of Arithmetic and Digit Span as a coherent working memory factor could not be verified, and Matrix Reasoning appeared to be isolated. With BCCD, some discrepancies from the proposed four-factor structure are exemplified. Furthermore, these results fit CHC theory of intelligence more clearly. Consistent clustering patterns indicate these results are robust. The structural causal discovery approach may be helpful in better interpreting existing tests, the development of new tests, and aid in diagnostic instruments.

Boko Haram: A Systemic and Strategic Analysis

DTIC Science & Technology

2016-06-01

21 5 Example Structural System Model …..……………………………….…………21 6 Interconnections ...…………………………………………………….…………23 vii 7...result from exogenous, endogenous, or structural factors. Endogenous factors exist within the geographical bounds of the system state, but exogenous...of the system, the structural factors are a result of the anarchic nature of the international system. Changes in system states reveal long-term

Factor structure and psychometric properties of english and spanish versions of the edinburgh postnatal depression scale among Hispanic women in a primary care setting.

PubMed

Hartley, Chelsey M; Barroso, Nicole; Rey, Yasmin; Pettit, Jeremy W; Bagner, Daniel M

2014-12-01

Although a number of studies have examined the factor structure of the Edinburgh Postnatal Depression Scale (EPDS) in predominately White or African American samples, no published research has reported on the factor structure among Hispanic women who reside in the United States. The current study examined the factor structure of the EPDS among Hispanic mothers in the United States. Among 220 Hispanic women, drawn from a pediatric primary care setting, with an infant aged 0 to 10 months, 6 structural models guided by the empirical literature were evaluated using confirmatory factor analysis. Results supported a 2-factor model of depression and anxiety as the best fitting model. Multigroup models supported the factorial invariance across women who completed the EDPS in English and Spanish. These findings provide initial support for the 2-factor structure of the EPDS among Hispanic women in the United States. © 2014 Wiley Periodicals, Inc.

Structural design/margin assessment

NASA Technical Reports Server (NTRS)

Ryan, R. S.

1993-01-01

Determining structural design inputs and the structural margins following design completion is one of the major activities in space exploration. The end result is a statement of these margins as stability, safety factors on ultimate and yield stresses, fracture limits (fracture control), fatigue lifetime, reuse criteria, operational criteria and procedures, stability factors, deflections, clearance, handling criteria, etc. The process is normally called a load cycle and is time consuming, very complex, and involves much more than structures. The key to successful structural design is the proper implementation of the process. It depends on many factors: leadership and management of the process, adequate analysis and testing tools, data basing, communications, people skills, and training. This process and the various factors involved are discussed.

The Construct Validity of Scores on the Ways of Coping Questionnaire: Confirmatory Analysis of Alternative Factor Structures.

ERIC Educational Resources Information Center

Edwards, Jeffrey R.; O'Neill, Regina M.

1998-01-01

Confirmatory factor analysis was used to evaluate alternative factor structures, based on previous exploratory factor analyses and coping dimensions derived from the theory of R. Lazarus, for the Ways of Coping Questionnaire (S. Folkman and R. Lazarus, 1988). Results from responses of 654 college graduates provide little support for the factor…

Selecting the "Best" Factor Structure and Moving Measurement Validation Forward: An Illustration.

PubMed

Schmitt, Thomas A; Sass, Daniel A; Chappelle, Wayne; Thompson, William

2018-04-09

Despite the broad literature base on factor analysis best practices, research seeking to evaluate a measure's psychometric properties frequently fails to consider or follow these recommendations. This leads to incorrect factor structures, numerous and often overly complex competing factor models and, perhaps most harmful, biased model results. Our goal is to demonstrate a practical and actionable process for factor analysis through (a) an overview of six statistical and psychometric issues and approaches to be aware of, investigate, and report when engaging in factor structure validation, along with a flowchart for recommended procedures to understand latent factor structures; (b) demonstrating these issues to provide a summary of the updated Posttraumatic Stress Disorder Checklist (PCL-5) factor models and a rationale for validation; and (c) conducting a comprehensive statistical and psychometric validation of the PCL-5 factor structure to demonstrate all the issues we described earlier. Considering previous research, the PCL-5 was evaluated using a sample of 1,403 U.S. Air Force remotely piloted aircraft operators with high levels of battlefield exposure. Previously proposed PCL-5 factor structures were not supported by the data, but instead a bifactor model is arguably more statistically appropriate.

Factor structure of the autonomy preference index in people with severe mental illness.

PubMed

Bonfils, Kelsey A; Adams, Erin L; Mueser, Kim T; Wright-Berryman, Jennifer L; Salyers, Michelle P

2015-08-30

People vary in the amount of control they want to exercise over decisions about their healthcare. Given the importance of patient-centered care, accurate measurement of these autonomy preferences is critical. This study aimed to assess the factor structure of the Autonomy Preference Index (API), used widely in general healthcare, in individuals with severe mental illness. Data came from two studies of people with severe mental illness (N=293) who were receiving mental health and/or primary care/integrated care services. Autonomy preferences were assessed with the API regarding both psychiatric and primary care services. Confirmatory factor analysis was used to evaluate fit of the hypothesized two-factor structure of the API (decision-making autonomy and information-seeking autonomy). Results indicated the hypothesized structure for the API did not adequately fit the data for either psychiatric or primary care services. Three problematic items were dropped, resulting in adequate fit for both types of treatment. These results suggest that with relatively minor modifications the API has an acceptable factor structure when asking people with severe mental illness about their preferences to be involved in decision-making. The modified API has clinical and research utility for this population in the burgeoning field of autonomy in patient-centered healthcare. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Moving Aerospace Structural Design Practice to a Load and Resistance Factor Approach

NASA Technical Reports Server (NTRS)

Larsen, Curtis E.; Raju, Ivatury S.

2016-01-01

Aerospace structures are traditionally designed using the factor of safety (FOS) approach. The limit load on the structure is determined and the structure is then designed for FOS times the limit load - the ultimate load. Probabilistic approaches utilize distributions for loads and strengths. Failures are predicted to occur in the region of intersection of the two distributions. The load and resistance factor design (LRFD) approach judiciously combines these two approaches by intensive calibration studies on loads and strength to result in structures that are efficient and reliable. This paper discusses these three approaches.

Factor structure of the Chinese version of the Meaning in Life Questionnaire among Hong Kong Chinese caregivers.

PubMed

Chan, Wallace Chi Ho

2014-08-01

This study examines the factor structure of the Chinese version of the Meaning in Life Questionnaire (C-MLQ) in a sample of Hong Kong Chinese caregivers of patients with chronic illness (N = 223). Confirmatory factor analysis was performed to examine the factor structure. Findings confirm that, identical to the original version, C-MLQ showed the same two-factor structure: Presence and Search. Correlation between Presence and Search was found to be positive and moderate (r = .47). This study establishes empirically the same factor structure as the original version of MLQ among caregivers in Hong Kong. The relationship between Presence and Meaning is discussed in the contexts of Chinese culture and caregiving. Results suggest caregivers' continuing need for meaning in life. Medical social workers may help caregivers to integrate their caregiving experience with their sense of meaning in life and search for meaning in life to sustain their caregiving role.

Population structure and landscape genetics of two endangered frog species of genus Odorrana: different scenarios on two islands

PubMed Central

Igawa, T; Oumi, S; Katsuren, S; Sumida, M

2013-01-01

Isolation by distance and landscape connectivity are fundamental factors underlying speciation and evolution. To understand how landscapes affect gene flow and shape population structures, island species provide intrinsic study objects. We investigated the effects of landscapes on the population structure of the endangered frog species, Odorrana ishikawae and O. splendida, which each inhabit an island in southwest Japan. This was done by examining population structure, gene flow and demographic history of each species by analyzing 12 microsatellite loci and exploring causal environmental factors through ecological niche modeling (ENM) and the cost-distance approach. Our results revealed that the limited gene flow and multiple-population structure in O. splendida and the single-population structure in O. ishikawae were maintained after divergence of the species through ancient vicariance between islands. We found that genetic distance correlated with geographic distance between populations of both species. Our landscape genetic analysis revealed that the connectivity of suitable habitats influences gene flow and leads to the formation of specific population structures. In particular, different degrees of topographical complexity between islands are the major determining factor for shaping contrasting population structures of two species. In conclusion, our results illustrate the diversification mechanism of organisms through the interaction with space and environment. Our results also present an ENM approach for identifying the key factors affecting demographic history and population structures of target species, especially endangered species. PMID:22990312

Consistency of Factor Structure on the Semantic Differential: An Analysis of Three Adult Samples.

ERIC Educational Resources Information Center

Sherry, David L.; Piotrowski, Chris

1986-01-01

The consistency of factor structure of Osgood's semantic differential was examined in three different adult samples, aged 18 to 87. Three different concepts were used: the University of West Florida, Myself, and Death. Results indicated consistency for the evaluation factor and moderate consistency for potency and activity. (Author/GDC)

Heterogeneity in the Latent Structure of PTSD Symptoms among Canadian Veterans

ERIC Educational Resources Information Center

Naifeh, James A.; Richardson, J. Don; Del Ben, Kevin S.; Elhai, Jon D.

2010-01-01

The current study used factor mixture modeling to identify heterogeneity (i.e., latent classes) in 2 well-supported models of posttraumatic stress disorder's (PTSD) factor structure. Data were analyzed from a clinical sample of 405 Canadian veterans evaluated for PTSD. Results were consistent with our hypotheses. Each PTSD factor model was best…

The Higher Order Factor Structure and Gender Invariance of the Pathological Narcissism Inventory

ERIC Educational Resources Information Center

Wright, Aidan G. C.; Lukowitsky, Mark R.; Pincus, Aaron L.; Conroy, David E.

2010-01-01

The Pathological Narcissism Inventory (PNI) is a recently developed multidimensional inventory for the assessment of pathological narcissism. The authors describe and report the results of two studies that investigate the higher order factor structure and gender invariance of the PNI. The results of the first study indicate that the PNI has a…

The cross-national structure of mental disorders: results from the World Mental Health Surveys.

PubMed

de Jonge, Peter; Wardenaar, Klaas J; Lim, Carmen C W; Aguilar-Gaxiola, Sergio; Alonso, Jordi; Andrade, Laura Helena; Bunting, Brendan; Chatterji, Somnath; Ciutan, Marius; Gureje, Oye; Karam, Elie G; Lee, Sing; Medina-Mora, Maria Elena; Moskalewicz, Jacek; Navarro-Mateu, Fernando; Pennell, Beth-Ellen; Piazza, Marina; Posada-Villa, José; Torres, Yolanda; Kessler, Ronald C; Scott, Kate

2017-12-19

The patterns of comorbidity among mental disorders have led researchers to model the underlying structure of psychopathology. While studies have suggested a structure including internalizing and externalizing disorders, less is known with regard to the cross-national stability of this model. Moreover, little data are available on the placement of eating disorders, bipolar disorder and psychotic experiences (PEs) in this structure. We evaluated the structure of mental disorders with data from the World Health Organization Composite International Diagnostic Interview, including 15 lifetime mental disorders and six PEs. Respondents (n = 5478-15 499) were included from 10 high-, middle- and lower middle-income countries across the world aged 18 years or older. Confirmatory factor analyses (CFAs) were used to evaluate and compare the fit of different factor structures to the lifetime disorder data. Measurement invariance was evaluated with multigroup CFA (MG-CFA). A second-order model with internalizing and externalizing factors and fear and distress subfactors best described the structure of common mental disorders. MG-CFA showed that this model was stable across countries. Of the uncommon disorders, bipolar disorder and eating disorder were best grouped with the internalizing factor, and PEs with a separate factor. These results indicate that cross-national patterns of lifetime common mental-disorder comorbidity can be explained with a second-order underlying structure that is stable across countries and can be extended to also cover less common mental disorders.

Factor Structure of a Multidimensional Gender Identity Scale in a Sample of Chinese Elementary School Children

PubMed Central

Yu, Lu; Xie, Dong; Shek, Daniel T. L.

2012-01-01

This study examined the factor structure of a scale based on the four-dimensional gender identity model (Egan and Perry, 2001) in 726 Chinese elementary school students. Exploratory factor analyses suggested a three-factor model, two of which corresponded to “Felt Pressure” and “Intergroup Bias” in the original model. The third factor “Gender Compatibility” appeared to be a combination of “Gender Typicality” and “Gender Contentment” in the original model. Follow-up confirmatory factor analysis (CFA) indicated that, relative to the initial four-factor structure, the three-factor model fits the current Chinese sample better. These results are discussed in light of cross-cultural similarities and differences in development of gender identity. PMID:22701363

Assessing a dysphoric arousal model of acute stress disorder symptoms in a clinical sample of rape and bank robbery victims.

PubMed

Hansen, Maj; Armour, Cherie; Elklit, Ask

2012-01-01

Since the introduction of Acute Stress Disorder (ASD) into the 4th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) research has focused on the ability of ASD to predict PTSD rather than focusing on addressing ASD's underlying latent structure. The few existing confirmatory factor analytic (CFA) studies of ASD have failed to reach a clear consensus regarding ASD's underlying dimensionality. Although, the discrepancy in the results may be due to varying ASD prevalence rates, it remains possible that the model capturing the latent structure of ASD has not yet been put forward. One such model may be a replication of a new five-factor model of PTSD, which separates the arousal symptom cluster into Dysphoric and Anxious Arousal. Given the pending DSM-5, uncovering ASD's latent structure is more pertinent than ever. USING CFA, FOUR DIFFERENT MODELS OF THE LATENT STRUCTURE OF ASD WERE SPECIFIED AND TESTED: the proposed DSM-5 model, the DSM-IV model, a three factor model, and a five factor model separating the arousal symptom cluster. The analyses were based on a combined sample of rape and bank robbery victims, who all met the diagnostic criteria for ASD (N = 404) using the Acute Stress Disorder Scale. The results showed that the five factor model provided the best fit to the data. The results of the present study suggest that the dimensionality of ASD may be best characterized as a five factor structure which separates dysphoric and anxious arousal items into two separate factors, akin to recent research on PTSD's latent structure. Thus, the current study adds to the debate about how ASD should be conceptualized in the pending DSM-5.

Confirmatory factor analysis of the Appraisal of Self-Care Agency Scale - Revised 1

PubMed Central

Stacciarini, Thaís Santos Guerra; Pace, Ana Emilia

2017-01-01

ABSTRACT Objective: to analyze the factor structure of the Appraisal of Self-Care Agency Scale-Revised (ASAS-R), adapted for Brazil. Method: methodological study conducted with 150 individuals with diabetes mellitus cared for by the Family Health Strategy, most of whom are elderly with low educational levels. The test of the hypothesis concerning the confirmatory factor composition of the ASAS-R was performed using latent variables structural equations. Results: the model’s goodness-of-fit indexes were satisfactory (χ2 = 259.19; χ2/g.l = 2.97, p < 0.001; GFI = 0.85; RMR = 0.07; RMSEA = 0.09); the factor loads were greater than 0.40; and most item-to-factor-correlations presented moderate to strong magnitude (0.34 to 0.58); total alpha value was 0.74, while the alpha of the three factors were 0.69, 0.38 and 0.69, respectively. Conclusion: the scale’s factor structure presented satisfactory validity and reliability results, with the exception of one factor. Application of this scale to samples of the general population is desirable in order to strengthen analyses of internal consistency and the dimensionality of the factor structure. This study is expected to contribute to further studies addressing the self-care agency construct and the development of the ASAS-R. PMID:28146182

Applying a Danish Version of the Learning Transfer System Inventory and Testing It for Different Types of Education

ERIC Educational Resources Information Center

Soerensen, Peter; Stegeager, Nikolaj; Bates, Reid

2017-01-01

The purpose of this study was to answer two research questions. First, will an exploratory factor analysis of a Danish version of the Learning Transfer System Inventory (LTSI) result in a factor structure which is consistent with the original American LTSI factor structure? Second, does the mean score in the factor analysis vary in a statistically…

Factor Structure of the Kessler Psychological Distress Scale (K6) among Emerging Adults

ERIC Educational Resources Information Center

Bessaha, Melissa L.

2017-01-01

Objective: Confirmatory factor analysis was used to assess the factor structure of the 6-item version of the Kessler Psychological Distress Scale (K6). Methods: A subsample of emerging adults, aged 18-29 (n = 20,699), from the 2013 National Survey of Drug Use and Health were used in this study. Results: Each of the models (one-factor, two-factor…

Factorial Validity of the ADHD Adult Symptom Rating Scale in a French Community Sample: Results From the ChiP-ARD Study.

PubMed

Morin, Alexandre J S; Tran, Antoine; Caci, Hervé

2016-06-01

Recent publications reported that a bifactor model better represented the underlying structure of ADHD than classical models, at least in youth. The Adult ADHD Symptoms Rating Scale (ASRS) has been translated into many languages, but a single study compared its structure in adults across Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) and International Classification of Diseases (ICD-10) classifications. We investigated the factor structure, reliability, and measurement invariance of the ASRS among a community sample of 1,171 adults. Results support a bifactor model, including one general ADHD factor and three specific Inattention, Hyperactivity, and Impulsivity factors corresponding to ICD-10, albeit the Impulsivity specific factor was weakly defined. Results also support the complete measurement invariance of this model across gender and age groups, and that men have higher scores than women on the ADHD G-factor but lower scores on all three S-factors. Results suggest that a total ASRS-ADHD score is meaningful, reliable, and valid in adults. (J. of Att. Dis. 2016; 20(6) 530-541). © The Author(s) 2013.

A two-factor theory for concussion assessment using ImPACT: memory and speed.

PubMed

Schatz, Philip; Maerlender, Arthur

2013-12-01

We present the initial validation of a two-factor structure of Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) using ImPACT composite scores and document the reliability and validity of this factor structure. Factor analyses were conducted for baseline (N = 21,537) and post-concussion (N = 560) data, yielding "Memory" (Verbal and Visual) and "Speed" (Visual Motor Speed and Reaction Time) Factors; inclusion of Total Symptom Scores resulted in a third discrete factor. Speed and Memory z-scores were calculated, and test-retest reliability (using intra-class correlation coefficients) at 1 month (0.88/0.81), 1 year (0.85/0.75), and 2 years (0.76/0.74) were higher than published data using Composite scores. Speed and Memory scores yielded 89% sensitivity and 70% specificity, which was higher than composites (80%/62%) and comparable with subscales (91%/69%). This emergent two-factor structure has improved test-retest reliability with no loss of sensitivity/specificity and may improve understanding and interpretability of ImPACT test results.

A Confirmatory Factor Analysis of the Structure of Abbreviated Math Anxiety Scale

PubMed Central

Farrokhi, Farahman

2011-01-01

Objective The aim of this study is to explore the confirmatory factor analysis results of the Persian adaptation of Abbreviated Math Anxiety Scale (AMAS), proposed by Hopko, Mahadevan, Bare & Hunt. Method The validity and reliability assessments of the scale were performed on 298 college students chosen randomly from Tabriz University in Iran. The confirmatory factor analysis (CFA) was carried out to determine the factor structures of the Persian version of AMAS. Results As expected, the two-factor solution provided a better fit to the data than a single factor. Moreover, multi-group analyses showed that this two-factor structure was invariant across sex. Hence, AMAS provides an equally valid measure for use among college students. Conclusions Brief AMAS demonstrates adequate reliability and validity. The AMAS scores can be used to compare symptoms of math anxiety between male and female students. The study both expands and adds support to the existing body of math anxiety literature. PMID:22952521

Measurement Invariance and Latent Mean Differences in the Reynolds Intellectual Assessment Scales (RIAS): Does the German Version of the RIAS Allow a Valid Assessment of Individuals with a Migration Background?

PubMed Central

Gygi, Jasmin T.; Fux, Elodie; Grob, Alexander; Hagmann-von Arx, Priska

2016-01-01

This study examined measurement invariance and latent mean differences in the German version of the Reynolds Intellectual Assessment Scales (RIAS) for 316 individuals with a migration background (defined as speaking German as a second language) and 316 sex- and age-matched natives. The RIAS measures general intelligence (single-factor structure) and its two components, verbal and nonverbal intelligence (two-factor structure). Results of a multi-group confirmatory factor analysis showed scalar invariance for the two-factor and partial scalar invariance for the single-factor structure. We conclude that the two-factor structure of the RIAS is comparable across groups. Hence, verbal and nonverbal intelligence but not general intelligence should be considered when comparing RIAS test results of individuals with and without a migration background. Further, latent mean differences especially on the verbal, but also on the nonverbal intelligence index indicate language barriers for individuals with a migration background, as subtests corresponding to verbal intelligence require higher skills in German language. Moreover, cultural, environmental, and social factors that have to be taken into account when assessing individuals with a migration background are discussed. PMID:27846270

[Does the GHQ-12 scoring system affect its factor structure? An exploratory study of Ibero American students].

PubMed

Urzúa, Alfonso; Caqueo-Urízar, Alejandra; Bargsted, Mariana; Irarrázaval, Matías

2015-06-01

This study aimed to evaluate whether the scoring system of the General Health Questionnaire (GHQ-12) alters the instrument's factor structure. The method considered 1,972 university students from nine Ibero American countries. Modeling was performed with structural equations for 1, 2, and 3 latent factors. The mechanism for scoring the questions was analyzed within each type of structure. The results indicate that models with 2 and 3 factors show better goodness-of-fit. In relation to scoring mechanisms, procedure 0-1-1-1 for models with 2 and 3 factors showed the best fit. In conclusion, there appears to be a relationship between the response format and the number of factors identified in the instrument's structure. The model with the best fit was 3-factor 0-1-1-1-formatted, but 0-1-2-3 has acceptable and more stable indicators and provides a better format for two- and three-dimensional models.

The factor structure of the Alcohol Use Disorders Identification Test (AUDIT).

PubMed

Doyle, Suzanne R; Donovan, Dennis M; Kivlahan, Daniel R

2007-05-01

Past research assessing the factor structure of the Alcohol Use Disorders Identification Test (AUDIT) with various exploratory and confirmatory factor analytic techniques has identified one-, two-, and three-factor solutions. Because different factor analytic procedures may result in dissimilar findings, we examined the factor structure of the AUDIT using the same factor analytic technique on two new large clinical samples and on archival data from six samples studied in previous reports. Responses to the AUDIT were obtained from participants who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), criteria for alcohol dependence in two large randomized clinical trials: the COMBINE (Combining Medications and Behavioral Interventions) Study (N = 1,337; 69% men) and Project MATCH (Matching Alcoholism Treatments to Client Heterogeneity; N = 1,711; 76% men). Supplementary analyses involved six correlation matrices of AUDIT data obtained from five previously published articles. Confirmatory factor analyses based on one-, two-, and three-factor models were conducted on the eight correlation matrices to assess the factor structure of the AUDIT. Across samples, analyses supported a correlated, two-factor solution representing alcohol consumption and alcohol-related consequences. The three-factor solution fit the data equally well, but two factors (alcohol dependence and harmful alcohol use) were highly correlated. The one-factor solution did not provide a good fit to the data. These findings support a two-factor solution for the AUDIT (alcohol consumption and alcohol-related consequences). The results contradict the original three-factor design of the AUDIT and the prevalent use of the AUDIT as a one-factor screening instrument with a single cutoff score.

The Attitudes to Chocolate Questionnaire: psychometric properties and relationship to dimensions of eating.

PubMed

Müller, Jochen; Dettmer, Dorothee; Macht, Michael

2008-01-01

The aim of the present study was to evaluate the psychometric properties of the Attitudes to Chocolate Questionnaire (ACQ). We analyzed the factor structure of the ACQ by conducting exploratory and confirmatory factor analyses in a sample of healthy adults and a sample of dietician students. Further, the relationship between the resulting ACQ factors and dimensions of eating behavior, personality, emotionality, and tests of the pleasantness, sweetness, and intensity of sugar and chocolate was examined. The results yielded a clear two-factor structure of the ACQ: The first factor (guilt) was composed of items concerning negative consequences of chocolate eating including the feeling of guilt. The second factor (craving) comprised items related to craving and emotional chocolate eating. Guilt correlated significantly with "emotional eating", "restrained eating", and with neuroticism. Craving correlated significantly with "emotional eating" and "external eating", with neuroticism, and with the "difficulty identifying feelings" facet of the Toronto Alexithymia Scale; further, it correlated highly with the average reported chocolate consumption and with the ratings of the intensity of taste of sugar. In conclusion, results support the validity of the German version of the ACQ and showed a stable factor structure and a good internal consistency.

Factor Structure of the Counselor Burnout Inventory in a Sample of Sexual Offender and Sexual Abuse Therapists

ERIC Educational Resources Information Center

Lee, Jayoung; Wallace, Sam; Puig, Ana; Choi, Bo Young; Nam, Suk Kyung; Lee, Sang Min

2010-01-01

This study empirically tested and compared three different models of factor structure with a sample of therapists working with sexual offenders, survivors of sexual abuse, or both. Results indicated that a modified five-factor model was the most appropriate. Practical implications for sexual offender/abuse survivor therapists are discussed.…

Homework Management Scale: Confirming the Factor Structure with Middle School Students in China

ERIC Educational Resources Information Center

Xu, Jianzhong; Fan, Xitao; Du, Jianxia

2015-01-01

This study presents a psychometric evaluation of the Homework Management Scale (HMS) for mathematics, consisting of five subscales for measuring homework management strategies. Confirmatory factor analyses were conducted with a sample of middle school students (N = 796). Results indicated that the factor structure of the Chinese version of the HMS…

Orthogonal Higher Order Structure of the WISC-IV Spanish Using Hierarchical Exploratory Factor Analytic Procedures

ERIC Educational Resources Information Center

McGill, Ryan J.; Canivez, Gary L.

2016-01-01

As recommended by Carroll, the present study examined the factor structure of the Wechsler Intelligence Scale for Children-Fourth Edition Spanish (WISC-IV Spanish) normative sample using higher order exploratory factor analytic techniques not included in the WISC-IV Spanish Technical Manual. Results indicated that the WISC-IV Spanish subtests were…

The Internal Structure of Positive and Negative Affect: A Confirmatory Factor Analysis of the PANAS

ERIC Educational Resources Information Center

Tuccitto, Daniel E.; Giacobbi, Peter R., Jr.; Leite, Walter L.

2010-01-01

This study tested five confirmatory factor analytic (CFA) models of the Positive Affect Negative Affect Schedule (PANAS) to provide validity evidence based on its internal structure. A sample of 223 club sport athletes indicated their emotions during the past week. Results revealed that an orthogonal two-factor CFA model, specifying error…

Optical-fiber strain sensors with asymmetric etched structures.

PubMed

Vaziri, M; Chen, C L

1993-11-01

Optical-fiber strain gauges with asymmetric etched structures have been analyzed, fabricated, and tested. These sensors are very sensitive with a gauge factor as high as 170 and a flat frequency response to at least 2.7 kHz. The gauge factor depends on the asymmetry of the etched structures and the number of etched sections. To understand the physical principles involved, researchers have used structural analysis programs based on a finite-element method to analyze fibers with asymmetric etched structures under tensile stress. The results show that lateral bends are induced on the etched fibers when they are stretched axially. To relate the lateral bending to the optical attenuation, we have also employed a ray-tracing technique to investigate the dependence of the attenuation on the structural deformation. Based on the structural analysis and the ray-tracing study parameters affecting the sensitivity have been studied. These results agree with the results of experimental investigations.

Revising the Child and Adolescent Perfectionism Scale: A Test of the Four-Factor Structure in a Chinese Sample

ERIC Educational Resources Information Center

Yang, Hongfei; Hong, Chaoqin; Tao, Xiaodan; Zhu, Lingyi

2015-01-01

This study examined the structure, reliability, and validity of the revised Chinese version of the Child and Adolescent Perfectionism Scale (N = 933). The results confirmed the four-factor structure of the Chinese version of the Child and Adolescent Perfectionism Scale. Implications, limitations, and suggestions for future research are provided.

Measurement invariance of the Illness Intrusiveness Ratings Scale's three-factor structure in men and women with cancer.

PubMed

Mah, Kenneth; Bezjak, Andrea; Loblaw, D Andrew; Gotowiec, Andrew; Devins, Gerald M

2011-02-01

Illness- and treatment-related disruptions to valued activities and interests (illness intrusiveness) are central to quality of life in chronic disease and are captured by three subscales of the Illness Intrusiveness Ratings Scale (IIRS): the Instrumental, Intimacy, and Relationships and Personal Development subscales. Using individual (CFA) and multisample confirmatory factor analyses (MSCFA), we evaluated measurement invariance of the IIRS's 3-factor structure in men and women with cancer. Men (n = 210) and women (n = 206) with 1 of 4 cancer diagnoses (gastrointestinal, head and neck, lymphoma, lung) recruited from outpatient clinics completed the IIRS. In the MSCFA, we applied an analysis of means and covariance structures approach to test increasingly stringent equality constraints on factor structure parameters to evaluate weak, strong, and strict measurement invariance of the 3-factor structure between men and women. Individual CFAs demonstrated fit of the hypothesized 3-factor structure for men and women, although more consistently for men. The 3-factor structure was superior to an alternative 1-factor structure. MSCFA results indicated that parameters of the 3-factor structure could be considered equivalent between the sexes up to the level of strong invariance. Strict invariance was not supported. Overall, IIRS scores can be interpreted similarly for men and women with cancer. Illness intrusiveness can be considered as important in the psychosocial adaptation of people with cancer as it is for people affected by other chronic conditions. (c) 2011 APA, all rights reserved

An examination of the factor structure of the Sociocultural Attitudes Towards Appearance Questionnaire-3 in Malaysia.

PubMed

Swami, Viren

2009-03-01

The present study examined the factor structure of a Malay translation of the Sociocultural Attitudes Towards Appearance Questionnaire-3 among a community sample of 554 Malaysian women. Results of an exploratory factor analysis revealed the existence of four factors, two of which (Information and Internalization-Athlete) mirrored those found among Western samples. An additional factor was an amalgamation of two factors reported in the West, namely Pressure and Internalization-General. A fourth factor consisted of six items, four of which cross-loaded onto previous factors, and was consequently dropped from analyses. Cronbach's alpha coefficients for the three retained factors were all above .82, and the three factors were significantly correlated with each other and with participants' body mass index. The results of this study stress the need for locally developed scales in the study of body image and a shift away from reliance on scales developed in the West.

A simple and accurate method for calculation of the structure factor of interacting charged spheres.

PubMed

Wu, Chu; Chan, Derek Y C; Tabor, Rico F

2014-07-15

Calculation of the structure factor of a system of interacting charged spheres based on the Ginoza solution of the Ornstein-Zernike equation has been developed and implemented on a stand-alone spreadsheet. This facilitates direct interactive numerical and graphical comparisons between experimental structure factors with the pioneering theoretical model of Hayter-Penfold that uses the Hansen-Hayter renormalisation correction. The method is used to fit example experimental structure factors obtained from the small-angle neutron scattering of a well-characterised charged micelle system, demonstrating that this implementation, available in the supplementary information, gives identical results to the Hayter-Penfold-Hansen approach for the structure factor, S(q) and provides direct access to the pair correlation function, g(r). Additionally, the intermediate calculations and outputs can be readily accessed and modified within the familiar spreadsheet environment, along with information on the normalisation procedure. Copyright © 2014 Elsevier Inc. All rights reserved.

Exploratory and Confirmatory Factor Analysis of the Career Decision-Making Difficulties Questionnaire

PubMed Central

Farrokhi, Farahman; Mahdavi, Ali; Moradi, Samad

2012-01-01

Objective The present study aimed at validating the structure of Career Decision-making Difficulties Questionnaire (CDDQ). Methods Five hundred and eleven undergraduate students took part in this research; from these participants, 63 males and 200 females took part in the first study, and 63 males and 185 females completed the survey for the second study. Results The results of exploratory factor analysis (EFA) indicated strong support for the three-factor structure, consisting of lack of information about the self, inconsistent information, lack of information and lack of readiness factors. A confirmatory factor analysis was run with the second sample using structural equation modeling. As expected, the three-factor solution provided a better fit to the data than the alternative models. Conclusion CDDQ was recommended to be used for college students in this study due to the fact that this instrument measures all three aspects of the model. Future research is needed to learn whether this model would fit other different samples. PMID:22952549

Bifactor latent structure of attention-deficit/hyperactivity disorder (ADHD)/oppositional defiant disorder (ODD) symptoms and first-order latent structure of sluggish cognitive tempo symptoms.

PubMed

Lee, SoYean; Burns, G Leonard; Beauchaine, Theodore P; Becker, Stephen P

2016-08-01

The objective was to determine if the latent structure of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms is best explained by a general disruptive behavior factor along with specific inattention (IN), hyperactivity/impulsivity (HI), and ODD factors (a bifactor model) whereas the latent structure of sluggish cognitive tempo (SCT) symptoms is best explained by a first-order factor independent of the bifactor model of ADHD/ODD. Parents' (n = 703) and teachers' (n = 366) ratings of SCT, ADHD-IN, ADHD-HI, and ODD symptoms on the Child and Adolescent Disruptive Behavior Inventory (CADBI) in a community sample of children (ages 5-13; 55% girls) were used to evaluate 4 models of symptom organization. Results indicated that a bifactor model of ADHD/ODD symptoms, in conjunction with a separate first-order SCT factor, was the best model for both parent and teacher ratings. The first-order SCT factor showed discriminant validity with the general disruptive behavior and specific IN factors in the bifactor model. In addition, higher scores on the SCT factor predicted greater academic and social impairment, even after controlling for the general disruptive behavior and 3 specific factors. Consistent with predictions from the trait-impulsivity etiological model of externalizing liability, a single, general disruptive behavior factor accounted for nearly all common variance in ADHD/ODD symptoms, whereas SCT symptoms represented a factor different from the general disruptive behavior and specific IN factor. These results provide additional support for distinguishing between SCT and ADHD-IN. The study also demonstrates how etiological models can be used to predict specific latent structures of symptom organization. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Orthogonal Higher Order Factor Structure of the Stanford-Binet Intelligence Scales--Fifth Edition for Children and Adolescents

ERIC Educational Resources Information Center

Canivez, Gary L.

2008-01-01

Orthogonal higher-order factor structure of the Stanford-Binet Intelligence Scales-Fifth Edition (SB-5; Roid, 2003a) for child and adolescent samples is reported. Multiple criteria for factor extraction unanimously supported extraction of only one dimension and a unidimensional model. However, following results from DiStefano and Dombrowski (2006)…

A closer look at the lower-order structure of the Personality Inventory for DSM-5: comparison with the Five-Factor Model.

PubMed

Griffin, Sarah A; Samuel, Douglas B

2014-10-01

The Personality Inventory for DSM-5 (PID-5) was developed as a measure of the maladaptive personality trait model included within Section III of the DSM-5. Although preliminary findings have suggested the PID-5 has a five-factor structure that overlaps considerably with the Five-Factor Model (FFM) at the higher order level, there has been much less attention on the specific locations of the 25 lower-order traits. Joint exploratory factor analysis of the PID-5 traits and the 30 facets of the NEO-PI-R were used to determine the lower-order structure of the PID-5. Results indicated the PID-5's domain-level structure closely resembled the FFM. We also explored the placement of several lower-order facets that have not loaded consistently in previous studies. Overall, these results indicate that the PID-5 shares a common structure with the FFM and clarify the placement of some interstitial facets. More research investigating the lower-order facets is needed to determine how they fit into the hierarchical structure and explicate their relationships to existing measures of pathological traits. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Factor structure of DSM-5 PTSD symptoms in trauma-exposed adolescents: Examining stability across time.

PubMed

Wang, Li; Cao, Xing; Cao, Chengqi; Fang, Ruojiao; Yang, Haibo; Elhai, Jon D

2017-12-01

This study investigated the latent structure of DSM-5 PTSD symptoms using two-wave longitudinal data collected from a sample of adolescents exposed to an explosion accident. Two waves of surveys were conducted approximately 3 and 8 months after the accident, respectively. A total of 836 students completed the baseline survey, and 762 students completed the follow-up survey. The results of confirmatory factor analyses(CFA) indicated that a seven-factor hybrid model composed of intrusion, avoidance, negative affect, anhedonia, externalizing behaviors, anxious arousal and dysphoric arousal factors yielded significantly better data fit at both waves than the other models including the DSM-5 four-factor model, the six-factor anhedonia and externalizing behaviors models. Furthermore, the results of CFA invariance tests supported the longitudinal invariance of the model. Implications and limitations in terms of these results are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Structural equation modelling of lower back pain due to whole-body vibration exposure in the construction industry.

PubMed

Vitharana, Vitharanage Hashini Paramitha; Chinda, Thanwadee

2017-09-21

Whole-body vibration (WBV) exposure is a health hazard among workers, causing lower back pain (LBP) in the construction industry. This study examines key factors affecting LBP due to WBV exposure using exploratory factor analysis and structural equation modelling. The results confirm five key factors (equipment, job related, organizational, personal, social context) with their 17 associated items. The organizational factor is found the most important, as it influences the other four factors. The results also show that appropriate seat type, specific training programme, job rotation, workers' satisfaction and workers' physical condition are crucial in reducing LBP due to WBV exposure. Moreover, provision of new machines without proper training and good working condition might not help reduce LBP due to WBV exposure. The results help the construction companies to better understand key factors affecting LBP due to WBV exposure, and to plan for a better health improvement programme.

Magnetic field effects on charge structure factors of gapped graphene structure

NASA Astrophysics Data System (ADS)

Rezania, Hamed; Tawoose, Nasrin

2018-02-01

We present the behaviors of dynamical and static charge susceptibilities of undoped gapped graphene using the Green's function approach in the context of tight binding model Hamiltonian. Specially, the effects of magnetic field on the plasmon modes of gapped graphene structure are investigated via calculating correlation function of charge density operators. Our results show the increase of magnetic field leads to disappear high frequency plasmon mode for gapped case. We also show that low frequency plasmon mode has not affected by increase of magnetic field and chemical potential. Finally the temperature dependence of static charge structure factor of gapp graphene structure is studied. The effects of both magnetic field and gap parameter on the static structure factor are discusses in details.

Unequal density effect on static structure factor of coupled electron layers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saini, L. K., E-mail: lks@ashd.svnit.ac.in; Nayak, Mukesh G., E-mail: lks@ashd.svnit.ac.in

In order to understand the ordered phase, if any, in a real coupled electron layers (CEL), there is a need to take into account the effect of unequal layer density. Such phase is confirmed by a strong peak in a static structure factor. With the aid of quantum/dynamical version of Singwi, Tosi, Land and Sjölander (so-called qSTLS) approximation, we have calculated the intra- and interlayer static structure factors, S{sub ll}(q) and S{sub 12}(q), over a wide range of density parameter r{sub sl} and interlayer spacing d. In our present study, the sharp peak in S{sub 22}(q) has been found atmore » critical density with sufficiently lower interlayer spacing. Further, to find the resultant effect of unequal density on intra- and interlayer static structure factors, we have compared our results with that of the recent CEL system with equal layer density and isolated single electron layer.« less

Factor structure of the Spanish version of the Patient Health Questionnaire-9 in Mexican women.

PubMed

Familiar, Itziar; Ortiz-Panozo, Eduardo; Hall, Brian; Vieitez, Isabel; Romieu, Isabelle; Lopez-Ridaura, Ruy; Lajous, Martin

2015-03-01

Structure of the Spanish version of the nine-item Patient Health Questionnaire (PHQ-9) has been inconclusive. We report the factor structure of the PHQ-9 in 55,555 women from the Mexican Teachers' Cohort (MTC). Factor structure of the PHQ-9 was assessed by exploratory and confirmatory factor analyses in two sub-samples (n = 27,778 and 27,777 respectively). A one-factor model of the PHQ-9 was the solution with the best fit to the data, exhibiting strong factor loadings (0.71 to 0.90) and high internal consistency (Cronbach's alpha = 0.89). A prevalence rate of moderate to high severity of depressive symptoms of 12.6% was identified. Results suggest that a global score is an appropriate measure of depressive symptoms and commend the use of the Spanish PHQ-9 as a measure of depression for research and clinical purposes. Copyright © 2014 John Wiley & Sons, Ltd.

Is the Dissociative Experiences Scale able to identify detachment and compartmentalization symptoms? Factor structure of the Dissociative Experiences Scale in a large sample of psychiatric and nonpsychiatric subjects

PubMed Central

Mazzotti, Eva; Farina, Benedetto; Imperatori, Claudio; Mansutti, Federica; Prunetti, Elena; Speranza, Anna Maria; Barbaranelli, Claudio

2016-01-01

Background In this study, we explored the ability of the Dissociative Experiences Scale (DES) to catch detachment and compartmentalization symptoms. Participants and methods The DES factor structure was evaluated in 768 psychiatric patients (546 women and 222 men) and in 2,403 subjects enrolled in nonpsychiatric settings (1,857 women and 546 men). All participants were administered the Italian version of DES. Twenty senior psychiatric experts in the treatment of dissociative symptoms independently assessed the DES items and categorized each of them as follows: “C” for compartmentalization, “D” for detachment, and “NC” for noncongruence with either C or D. Results Confirmatory factor analysis supported the three-factor structure of DES in both clinical and nonclinical samples and its invariance across the two groups. Moreover, factor analyses results overlapped with those from the expert classification procedure. Conclusion Our results showed that DES can be used as a valid instrument for clinicians to assess the frequency of different types of dissociative experiences including detachment and compartmentalization. PMID:27350746

The role of dispersal mode and habitat specialization for metacommunity structure of shallow beach invertebrates.

PubMed

Rodil, Iván F; Lucena-Moya, Paloma; Jokinen, Henri; Ollus, Victoria; Wennhage, Håkan; Villnäs, Anna; Norkko, Alf

2017-01-01

Metacommunity ecology recognizes the interplay between local and regional patterns in contributing to spatial variation in community structure. In aquatic systems, the relative importance of such patterns depends mainly on the potential connectivity of the specific system. Thus, connectivity is expected to increase in relation to the degree of water movement, and to depend on the specific traits of the study organism. We examined the role of environmental and spatial factors in structuring benthic communities from a highly connected shallow beach network using a metacommunity approach. Both factors contributed to a varying degree to the structure of the local communities suggesting that environmental filters and dispersal-related mechanisms played key roles in determining abundance patterns. We categorized benthic taxa according to their dispersal mode (passive vs. active) and habitat specialization (generalist vs. specialist) to understand the relative importance of environment and dispersal related processes for shallow beach metacommunities. Passive dispersers were predicted by a combination of environmental and spatial factors, whereas active dispersers were not spatially structured and responded only to local environmental factors. Generalists were predicted primarily by spatial factors, while specialists were only predicted by local environmental factors. The results suggest that the role of the spatial component in metacommunity organization is greater in open coastal waters, such as shallow beaches, compared to less-connected environmentally controlled aquatic systems. Our results also reveal a strong environmental role in structuring the benthic metacommunity of shallow beaches. Specifically, we highlight the sensitivity of shallow beach macrofauna to environmental factors related to eutrophication proxies.

The role of dispersal mode and habitat specialization for metacommunity structure of shallow beach invertebrates

PubMed Central

Lucena-Moya, Paloma; Jokinen, Henri; Ollus, Victoria; Wennhage, Håkan; Villnäs, Anna; Norkko, Alf

2017-01-01

Metacommunity ecology recognizes the interplay between local and regional patterns in contributing to spatial variation in community structure. In aquatic systems, the relative importance of such patterns depends mainly on the potential connectivity of the specific system. Thus, connectivity is expected to increase in relation to the degree of water movement, and to depend on the specific traits of the study organism. We examined the role of environmental and spatial factors in structuring benthic communities from a highly connected shallow beach network using a metacommunity approach. Both factors contributed to a varying degree to the structure of the local communities suggesting that environmental filters and dispersal-related mechanisms played key roles in determining abundance patterns. We categorized benthic taxa according to their dispersal mode (passive vs. active) and habitat specialization (generalist vs. specialist) to understand the relative importance of environment and dispersal related processes for shallow beach metacommunities. Passive dispersers were predicted by a combination of environmental and spatial factors, whereas active dispersers were not spatially structured and responded only to local environmental factors. Generalists were predicted primarily by spatial factors, while specialists were only predicted by local environmental factors. The results suggest that the role of the spatial component in metacommunity organization is greater in open coastal waters, such as shallow beaches, compared to less-connected environmentally controlled aquatic systems. Our results also reveal a strong environmental role in structuring the benthic metacommunity of shallow beaches. Specifically, we highlight the sensitivity of shallow beach macrofauna to environmental factors related to eutrophication proxies. PMID:28196112

Ab initio simulations of the dynamic ion structure factor of warm dense lithium

DOE PAGES

Witte, B. B. L.; Shihab, M.; Glenzer, S. H.; ...

2017-04-06

Here, we present molecular dynamics simulations based on finite-temperature density functional theory that determine self-consistently the dynamic ion structure factor and the electronic form factor in lithium. Our comprehensive data set allows for the calculation of the dispersion relation for collective excitations, the calculation of the sound velocity, and the determination of the ion feature from the total electronic form factor and the ion structure factor. The results are compared with available experimental x-ray and neutron scattering data. Good agreement is found for both the liquid metal and warm dense matter domain. Finally, we study the impact of possible targetmore » inhomogeneities on x-ray scattering spectra.« less

Ab initio simulations of the dynamic ion structure factor of warm dense lithium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Witte, B. B. L.; Shihab, M.; Glenzer, S. H.

Here, we present molecular dynamics simulations based on finite-temperature density functional theory that determine self-consistently the dynamic ion structure factor and the electronic form factor in lithium. Our comprehensive data set allows for the calculation of the dispersion relation for collective excitations, the calculation of the sound velocity, and the determination of the ion feature from the total electronic form factor and the ion structure factor. The results are compared with available experimental x-ray and neutron scattering data. Good agreement is found for both the liquid metal and warm dense matter domain. Finally, we study the impact of possible targetmore » inhomogeneities on x-ray scattering spectra.« less

Orthogonal higher order structure and confirmatory factor analysis of the French Wechsler Adult Intelligence Scale (WAIS-III).

PubMed

Golay, Philippe; Lecerf, Thierry

2011-03-01

According to the most widely accepted Cattell-Horn-Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS-III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a Schmid-Leiman orthogonalization transformation (SLT) to the standardization data published in the French technical manual for the WAIS-III. Results showed that the general factor accounted for 63% of the common variance and that the specific contributions of the 1st-order factors were weak (4.7%-15.9%). We also addressed this issue by using confirmatory factor analysis. Results indicated that the bifactor model (with 1st-order group and general factors) better fit the data than did the traditional higher order structure. Models based on the CHC framework were also tested. Results indicated that a higher order CHC model showed a better fit than did the classical 4-factor model; however, the WAIS bifactor structure was the most adequate. We recommend that users do not discount the Full Scale IQ when interpreting the index scores of the WAIS-III because the general factor accounts for the bulk of the common variance in the French WAIS-III. The 4 index scores cannot be considered to reflect only broad ability because they include a strong contribution of the general factor.

An examination of the factor structure and sex invariance of a French translation of the Body Appreciation Scale-2 in university students.

PubMed

Kertechian, Sevag; Swami, Viren

2017-06-01

The Body Appreciation Scale-2 (BAS-2) is a measure of positive body image that has been found that have a one-dimensional factor structure in a number of different cultural groups. Here, we examined the factor structure and sex-based measurement invariance of a French translation of the BAS-2. A total of 652 university students (age M=21.33, SD=3.18) completed a newly-translated French version of the BAS-2. Exploratory factor analyses with a randomly selected split-half subsample revealed that the BAS-2 had a one-dimensional factor structure in both sexes. Confirmatory factor analyses with a second split-half subsample indicated that the one-dimensional factor structure had adequate fit following modifications and was invariant across sex. French BAS-2 scores had adequate internal consistency and men had significantly higher body appreciation than women (ds=.16-.23). These results provide preliminary support for the factorial validity of the French BAS-2. Copyright © 2017 Elsevier Ltd. All rights reserved.

Factor Analysis of the Brazilian Version of UPPS Impulsive Behavior Scale.

PubMed

Sediyama, Cristina Y N; Moura, Ricardo; Garcia, Marina S; da Silva, Antonio G; Soraggi, Carolina; Neves, Fernando S; Albuquerque, Maicon R; Whiteside, Setephen P; Malloy-Diniz, Leandro F

2017-01-01

Objective: To examine the internal consistency and factor structure of the Brazilian adaptation of the UPPS Impulsive Behavior Scale. Methods: UPPS is a self-report scale composed by 40 items assessing four factors of impulsivity: (a) urgency, (b) lack of premeditation; (c) lack of perseverance; (d) sensation seeking. In the present study 384 participants (278 women and 106 men), who were recruited from schools, universities, leisure centers and workplaces fulfilled the UPPS scale. An exploratory factor analysis was performed by using Varimax factor rotation and Kaiser Normalization, and we also conducted two confirmatory analyses to test the independency of the UPPS components found in previous analysis. Results: Results showed a decrease in mean UPPS total scores with age and this analysis showed that the youngest participants (below 30 years) scored significantly higher than the other groups over 30 years. No difference in gender was found. Cronbach's alpha, results indicated satisfactory values for all subscales, with similar high values for the subscales and confirmatory factor analysis indexes also indicated a poor model fit. The results of two exploratory factor analysis were satisfactory. Conclusion: Our results showed that the Portuguese version has the same four-factor structure of the original and previous translations of the UPPS.

Three-factor structure for Epistemic Belief Inventory: A cross-validation study

PubMed Central

2017-01-01

Research on epistemic beliefs has been hampered by lack of validated models and measurement instruments. The most widely used instrument is the Epistemological Questionnaire, which has been criticized for validity, and it has been proposed a new instrument based in the Epistemological Questionnaire: the Epistemic Belief Inventory. The Spanish-language version of Epistemic Belief Inventory was applied to 1,785 Chilean high school students. Exploratory and confirmatory factor analyses in independent subsamples were performed. A three factor structure emerged and was confirmed. Reliability was comparable to other studies, and the factor structure was invariant among randomized subsamples. The structure that was found does not replicate the one proposed originally, but results are interpreted in light of embedded systemic model of epistemological beliefs. PMID:28278258

Structural invariance of multiple intelligences, based on the level of execution.

PubMed

Almeida, Leandro S; Prieto, María Dolores; Ferreira, Arístides; Ferrando, Mercedes; Ferrandiz, Carmen; Bermejo, Rosario; Hernández, Daniel

2011-11-01

The independence of multiple intelligences (MI) of Gardner's theory has been debated since its conception. This article examines whether the one- factor structure of the MI theory tested in previous studies is invariant for low and high ability students. Two hundred ninety-four children (aged 5 to 7) participated in this study. A set of Gardner's Multiple Intelligence assessment tasks based on the Spectrum Project was used. To analyze the invariance of a general dimension of intelligence, the different models of behaviours were studied in samples of participants with different performance on the Spectrum Project tasks with Multi-Group Confirmatory Factor Analysis (MGCFA). Results suggest an absence of structural invariance in Gardner's tasks. Exploratory analyses suggest a three-factor structure for individuals with higher performance levels and a two-factor structure for individuals with lower performance levels.

Can Parental Bonding Be Assessed in Children? Factor Structure and Factorial Invariance of the Parental Bonding Instrument (PBI) between Adults and Children

ERIC Educational Resources Information Center

Tsaousis, Ioannis; Mascha, Katerina; Giovazolias, Theodoros

2012-01-01

This study examined the factorial structure of the Parental Bonding Instrument (PBI) in the Greek population. Using confirmatory factor analysis different proposed models of the basic dimensions of PBI were evaluated. The results indicated that Kendler's three-factor (i.e. care, protectiveness and authoritarianism) solution was found to be more…

Transforming Static Data Structures to Dynamic Structures.

DTIC Science & Technology

1979-09-03

binary transform. and was then studied in detail by Bentley. Oetiq. Guihms and Saxe E 1979). The name is taken Porn its similarity t the binomial qeeue...costs of the two families of structures would have been equal within a constant factor, each being 0(N3 1 2 ). The present disparity suggests that it...cost being split evenly (within a constant factor) between the two families of structures. The preceding results may be generalized to arbitrary

Examination of the Beck Depression Inventory-II Factor Structure Among Bariatric Surgery Candidates.

PubMed

Hayes, Sharon; Stoeckel, Nina; Napolitano, Melissa A; Collins, Charlotte; Wood, G Craig; Seiler, Jamie; Grunwald, Heidi E; Foster, Gary D; Still, Christopher D

2015-07-01

The Beck Depression Inventory-II (BDI-II) is frequently used to evaluate bariatric patients in clinical and research settings; yet, there are limited data regarding the factor structure of the BDI-II with a bariatric surgery population. Exploratory factor analysis (EFA) using principal axis factoring with oblimin rotation was employed with data from 1228 consecutive presurgical bariatric candidates. Independent t tests were used to examine potential differences between sexes. Confirmatory factor analysis (CFA) was conducted with the next 383 consecutive presurgical patients to evaluate the proposed model based on EFA results. EFA revealed three factors: negative perceptions, diminished vigor, and cognitive dysregulation, each with adequate internal consistency. Six BDI-II items did not load significantly on any of the three factors. CFA results largely supported the proposed model. Results suggest that dimensions of depression for presurgical bariatric candidates vary from other populations and raise important caveats regarding the utility of the BDI-II in bariatric research.

State Effect of Traumatic Experience on Personality Structure

PubMed Central

Lee, Hong-seock; Lee, Sang-Kyu; Lee, Heung-Pyo

2012-01-01

Objective Personality is defined as the trait-like qualities of a person. However, it has been recently suggested that the state effect of a situation leads to changes in scores on personality assessments. We predicted that traumatic experiences would induce changes not only in personality scores but also in the factor structures of personality assessments. Methods MethodsaaWe conducted a cross-sectional, case-controlled study using two data sets: a traumatized adolescent sample (n=71) and a non-traumatized adolescent sample (n=296). Personality factor structures were compared between the two samples using exploratory factor analyses for 25 lower-ordered subscales of the Temperament and Character Inventory (TCI). In the non-traumatized sample, evaluation of the scree plot suggested a five-factor solution supporting TCI's original seven-factor model. Results The traumatized sample showed a three-factor structure representing a biological factor, a social factor and an existential factor. This decrease in number of personality factors was caused by strengthened correlations among personality subscales related to coping with traumatic situations. Cloninger's psychobiological model of personality (i.e., temperament-character) was adequate in capturing personality traits of non-traumatized adolescents, but the tripartite view of existential psychology (i.e., body-mind-spirit) clearly corresponded to the factor structure of the traumatized adolescents. Conclusion The three-factor solution of the present traumatized group is consistent with the tripartite model of personality (i.e., body-mind-spirit), while the five-factor solution of the non-traumatized group corresponds to Cloninger's seven-factor model. This is the first study to describe the state effects of traumatic experiences on personality structure. PMID:23251200

Hispanic ethnicity and Caucasian race: Relations with posttraumatic stress disorder's factor structure in clinic-referred youth.

PubMed

Contractor, Ateka A; Claycomb, Meredith A; Byllesby, Brianna M; Layne, Christopher M; Kaplow, Julie B; Steinberg, Alan M; Elhai, Jon D

2015-09-01

The severity of posttraumatic stress disorder (PTSD) symptoms is linked to race and ethnicity, albeit with contradictory findings (reviewed in Alcántara, Casement, & Lewis-Fernández, 2013; Pole, Gone, & Kulkarni, 2008). We systematically examined Caucasian (n = 3,767) versus non-Caucasian race (n = 2,824) and Hispanic (n = 2,395) versus non-Hispanic ethnicity (n = 3,853) as candidate moderators of PTSD's 5-factor model structural parameters (Elhai et al., 2013). The sample was drawn from the National Child Traumatic Stress Network's Core Data Set, currently the largest national data set of clinic-referred children and adolescents exposed to potentially traumatic events. Using confirmatory factor analysis, we tested the invariance of PTSD symptom structural parameters by race and ethnicity. Chi-square difference tests and goodness-of-fit values showed statistical equivalence across racial and ethnic groups in the factor structure of PTSD and in mean item-level indicators of PTSD symptom severity. Results support the structural invariance of PTSD's 5-factor model across the compared racial and ethnic groups. Furthermore, results indicated equivalent item-level severity across racial and ethnic groups; this supports the use of item-level comparisons across these groups. (c) 2015 APA, all rights reserved).

Personality of Wild Male Crested Macaques (Macaca nigra)

PubMed Central

Neumann, Christof; Agil, Muhammad; Widdig, Anja; Engelhardt, Antje

2013-01-01

Animal personalities, i.e. consistent differences in behavior across time and/or context, have received increased attention of behavioral biologists over the last years. Recent research shows that personalities represent traits on which natural and sexual selection work and which can have substantial fitness consequences. The aim of this study is to establish the personality structure of crested macaque (Macaca nigra) males as foundation for future studies on its adaptive value. We collected behavioral data through focal animal sampling and additionally conducted two sets of playback experiments. Results of a factor analysis on the behavioral data revealed a four factor structure with components we labeled Anxiety, Sociability, Connectedness and Aggressiveness. Results from the experiments revealed an additional and independent Boldness factor but the absence of Neophilia. Overall, this structure resembles other macaque and animal species with the exception of Connectedness, which might be a consequence of the species' tolerant social style. Our results thus not only form the basis for future studies on the adaptive value of personality in crested macaques but also contribute an important data point for investigating the evolution of personality structure from a comparative perspective by refining, for example, which personality factors characterized the last common ancestor of hominids and macaques. PMID:23940517

Psychometric Properties of the “Sport Motivation Scale (SMS)” Adapted to Physical Education

PubMed Central

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

Examining the Factor Structure of the MLQ Transactional and Transformational Leadership Dimensions in Nursing Context.

PubMed

Boamah, Sheila A; Tremblay, Paul

2018-05-01

The Multifactor Leadership Questionnaire (MLQ) is the most widely used instrument for assessing dimensions of leadership style; yet, most studies have failed to reproduce the original MLQ factor structure. The current study evaluates the dimensionality and nomological validity of Bass's transactional and transformational leadership model using the MLQ in a sample of registered nurses working in acute care hospitals in Canada. A combination of exploratory and confirmatory factor analyses were used to evaluate the hypothetical factor structure of the MLQ consisting of five transformational factors, and three transactional factors. Results suggest that the eight-factor solution displayed best fit indices; however, two transactional factors should be extracted due to high interscale correlations and lack of differential relationships with the two leadership variables. The findings support a scale refinement and the need for new theory concerning the five transformational leadership and contingent reward dimensions of the MLQ.

The factor structure of the Values in Action Inventory of Strengths (VIA-IS): An item-level exploratory structural equation modeling (ESEM) bifactor analysis.

PubMed

Ng, Vincent; Cao, Mengyang; Marsh, Herbert W; Tay, Louis; Seligman, Martin E P

2017-08-01

The factor structure of the Values in Action Inventory of Strengths (VIA-IS; Peterson & Seligman, 2004) has not been well established as a result of methodological challenges primarily attributable to a global positivity factor, item cross-loading across character strengths, and questions concerning the unidimensionality of the scales assessing character strengths. We sought to overcome these methodological challenges by applying exploratory structural equation modeling (ESEM) at the item level using a bifactor analytic approach to a large sample of 447,573 participants who completed the VIA-IS with all 240 character strengths items and a reduced set of 107 unidimensional character strength items. It was found that a 6-factor bifactor structure generally held for the reduced set of unidimensional character strength items; these dimensions were justice, temperance, courage, wisdom, transcendence, humanity, and an overarching general factor that is best described as dispositional positivity. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Further insights on the French WISC-IV factor structure through Bayesian structural equation modeling.

PubMed

Golay, Philippe; Reverte, Isabelle; Rossier, Jérôme; Favez, Nicolas; Lecerf, Thierry

2013-06-01

The interpretation of the Wechsler Intelligence Scale for Children--Fourth Edition (WISC-IV) is based on a 4-factor model, which is only partially compatible with the mainstream Cattell-Horn-Carroll (CHC) model of intelligence measurement. The structure of cognitive batteries is frequently analyzed via exploratory factor analysis and/or confirmatory factor analysis. With classical confirmatory factor analysis, almost all cross-loadings between latent variables and measures are fixed to zero in order to allow the model to be identified. However, inappropriate zero cross-loadings can contribute to poor model fit, distorted factors, and biased factor correlations; most important, they do not necessarily faithfully reflect theory. To deal with these methodological and theoretical limitations, we used a new statistical approach, Bayesian structural equation modeling (BSEM), among a sample of 249 French-speaking Swiss children (8-12 years). With BSEM, zero-fixed cross-loadings between latent variables and measures are replaced by approximate zeros, based on informative, small-variance priors. Results indicated that a direct hierarchical CHC-based model with 5 factors plus a general intelligence factor better represented the structure of the WISC-IV than did the 4-factor structure and the higher order models. Because a direct hierarchical CHC model was more adequate, it was concluded that the general factor should be considered as a breadth rather than a superordinate factor. Because it was possible for us to estimate the influence of each of the latent variables on the 15 subtest scores, BSEM allowed improvement of the understanding of the structure of intelligence tests and the clinical interpretation of the subtest scores. PsycINFO Database Record (c) 2013 APA, all rights reserved.

The structure of cockpit management attitudes

NASA Technical Reports Server (NTRS)

Gregorich, S. E.; Helmreich, R. L.; Wilhelm, J. A.

1990-01-01

A revised version of the Cockpit Management Attitudes Questionnaire (CMAQ) is introduced. Factor analyses of responses from 3 different samples reveal comparable factor structure (previous attempts to factor analyze this measure had produced equivocal results). Implications for the measurement of attitudes and the assessment of attitude change are discussed. It is argued that the CMAQ will benefit both special training programs and efforts to explore attitude-performance linkages in air-transport operations.

Thermodynamic properties and static structure factor for a Yukawa fluid in the mean spherical approximation.

PubMed

Montes-Perez, J; Cruz-Vera, A; Herrera, J N

2011-12-01

This work presents the full analytic expressions for the thermodynamic properties and the static structure factor for a hard sphere plus 1-Yukawa fluid within the mean spherical approximation. To obtain these properties of the fluid type Yukawa analytically it was necessary to solve an equation of fourth order for the scaling parameter on a large scale. The physical root of this equation was determined by imposing physical conditions. The results of this work are obtained from seminal papers of Blum and Høye. We show that is not necessary the use the series expansion to solve the equation for the scaling parameter. We applied our theoretical result to find the thermodynamic and the static structure factor for krypton. Our results are in good agreement with those obtained in an experimental form or by simulation using the Monte Carlo method.

Social disorganization and the profile of child welfare: Explaining child welfare activity by the community-level factors.

PubMed

Harrikari, Timo

2014-10-01

This article addresses the question of the structure of local child welfare activities in light of community-level factors. It poses the following research questions: how are different community-level factors related to child welfare client structures in communities and what is the extent to which these factors explain structural differences? The applied theoretical framework is based on social disorganization and strain theories as well as human developmental approach. The data has been collected from two Finnish national databases and it consists of variables containing 257 Finnish municipalities. The method of analysis is multinomial logistic regression. The results suggest that the local child welfare structures are tied to social disorganization, policing and culture as well as to the intensity of control in the communities. In general, the more fragile the communal structures, the more last-resort child welfare there is in the community. Combining fragile communal structures with weak dependency ratio and high proportion of social workers, the more intense the level of child welfare statistics indicated. The results indicate that the theoretical framework for the application of child welfare activity analysis is justified, but they also suggest that it requires further development through both context-bound reflection and application. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dimensionality and measurement invariance in the Satisfaction with Life Scale in Norway.

PubMed

Clench-Aas, Jocelyne; Nes, Ragnhild Bang; Dalgard, Odd Steffen; Aarø, Leif Edvard

2011-10-01

Results from previous studies examining the dimensionality and factorial invariance of the Satisfaction with Life Scale (SWLS) are inconsistent and often based on small samples. This study examines the factorial structure and factorial invariance of the SWLS in a Norwegian sample. Confirmatory factor analysis (AMOS) was conducted to explore dimensionality and test for measurement invariance in factor structure, factor loadings, intercepts, and residual variance across gender and four age groups in a large (N = 4,984), nationally representative sample of Norwegian men and women (15-79 years). The data supported a modified unidimensional structure. Factor loadings could be constrained to equality between the sexes, indicating metric invariance between genders. Further testing indicated invariance also at the strong and strict levels, thus allowing analyses involving group means. The SWLS was shown to be sensitive to age, however, at the strong and strict levels of invariance testing. In conclusion, the results in this Norwegian study seem to confirm that a unidimensional structure is acceptable, but that a modified single-factor model with correlations between error terms of items 4 and 5 is preferred. Additionally, comparisons may be made between the genders. Caution must be exerted when comparing age groups.

Perturbation of Chromatin Structure Globally Affects Localization and Recruitment of Splicing Factors

PubMed Central

Risso, Guillermo J.; Pawellek, Andrea; Ule, Jernej; Lamond, Angus I.; Kornblihtt, Alberto R.

2012-01-01

Chromatin structure is an important factor in the functional coupling between transcription and mRNA processing, not only by regulating alternative splicing events, but also by contributing to exon recognition during constitutive splicing. We observed that depolarization of neuroblastoma cell membrane potential, which triggers general histone acetylation and regulates alternative splicing, causes a concentration of SR proteins in nuclear speckles. This prompted us to analyze the effect of chromatin structure on splicing factor distribution and dynamics. Here, we show that induction of histone hyper-acetylation results in the accumulation in speckles of multiple splicing factors in different cell types. In addition, a similar effect is observed after depletion of the heterochromatic protein HP1α, associated with repressive chromatin. We used advanced imaging approaches to analyze in detail both the structural organization of the speckle compartment and nuclear distribution of splicing factors, as well as studying direct interactions between splicing factors and their association with chromatin in vivo. The results support a model where perturbation of normal chromatin structure decreases the recruitment efficiency of splicing factors to nascent RNAs, thus causing their accumulation in speckles, which buffer the amount of free molecules in the nucleoplasm. To test this, we analyzed the recruitment of the general splicing factor U2AF65 to nascent RNAs by iCLIP technique, as a way to monitor early spliceosome assembly. We demonstrate that indeed histone hyper-acetylation decreases recruitment of U2AF65 to bulk 3′ splice sites, coincident with the change in its localization. In addition, prior to the maximum accumulation in speckles, ∼20% of genes already show a tendency to decreased binding, while U2AF65 seems to increase its binding to the speckle-located ncRNA MALAT1. All together, the combined imaging and biochemical approaches support a model where chromatin structure is essential for efficient co-transcriptional recruitment of general and regulatory splicing factors to pre-mRNA. PMID:23152763

Role of carbohydrate in multimeric structure of factor VIII/von Willebrand factor protein.

PubMed Central

Gralnick, H R; Williams, S B; Rick, M E

1983-01-01

The carbohydrate moiety of the factor VIII/von Willebrand (vW) factor protein is important in the expression of vW factor activity and the intravascular survival of the protein. Studies of normal human factor VIII/vW factor protein indicate that there is a requirement of a full complement of penultimate galactose for the maintenance of a normal multimeric structure. Release of penultimate galactose by beta-galactosidase or modification by galactose oxidase results in loss of the largest molecular weight multimers and increased numbers of intermediate and smaller multimers. In contrast, terminal galactose on the factor VIII/vW factor protein does not appear to play a significant role in the maintenance of the multimer organization. The abnormalities in multimeric structure and molecular size were demonstrated by NaDodSO4/polyacrylamide/agarose gel electrophoresis, NaDodSO4/glyoxyl-agarose electrophoresis, and sucrose density ultracentrifugation. These studies indicate that the penultimate galactose plays a role in the maintenance of the largest multimers of the factor VIII/vW factor protein. This may explain why, in some patients with variant forms of vW disease, a carbohydrate abnormality also may affect the multimeric structure of the plasma factor VIII/vW factor protein. Images PMID:6601805

Structural Model of psychological risk and protective factors affecting on quality of life in patients with coronary heart disease: A psychocardiology model

PubMed Central

Nekouei, Zohreh Khayyam; Yousefy, Alireza; Doost, Hamid Taher Neshat; Manshaee, Gholamreza; Sadeghei, Masoumeh

2014-01-01

Background: Conducted researches show that psychological factors may have a very important role in the etiology, continuity and consequences of coronary heart diseases. This study has drawn the psychological risk and protective factors and their effects in patients with coronary heart diseases (CHD) in a structural model. It aims to determine the structural relations between psychological risk and protective factors with quality of life in patients with coronary heart disease. Materials and Methods: The present cross-sectional and correlational studies were conducted using structural equation modeling. The study sample included 398 patients of coronary heart disease in the university referral Hospital, as well as other city health care centers in Isfahan city. They were selected based on random sampling method. Then, in case, they were executed the following questionnaires: Coping with stressful situations (CISS- 21), life orientation (LOT-10), general self-efficacy (GSE-10), depression, anxiety and stress (DASS-21), perceived stress (PSS-14), multidimensional social support (MSPSS-12), alexithymia (TAS-20), spiritual intelligence (SQ-23) and quality of life (WHOQOL-26). Results: The results showed that protective and risk factors could affect the quality of life in patients with CHD with factor loadings of 0.35 and −0.60, respectively. Moreover, based on the values of the framework of the model such as relative chi-square (CMIN/DF = 3.25), the Comparative Fit Index (CFI = 0.93), the Parsimony Comparative Fit Index (PCFI = 0.68), the Root Mean Square Error of Approximation (RMSEA = 0.07) and details of the model (significance of the relationships) it has been confirmed that the psychocardiological structural model of the study is the good fitting model. Conclusion: This study was among the first to research the different psychological risk and protective factors of coronary heart diseases in the form of a structural model. The results of this study have emphasized the necessity of noticing the psychological factors in primary prevention by preventive programs and in secondary prevention by rehabilitation centers to improve the quality of life of the people with heart diseases. PMID:24778660

Automated processing of first-pass radionuclide angiocardiography by factor analysis of dynamic structures.

PubMed

Cavailloles, F; Bazin, J P; Capderou, A; Valette, H; Herbert, J L; Di Paola, R

1987-05-01

A method for automatic processing of cardiac first-pass radionuclide study is presented. This technique, factor analysis of dynamic structures (FADS) provides an automatic separation of anatomical structures according to their different temporal behaviour, even if they are superimposed. FADS has been applied to 76 studies. A description of factor patterns obtained in various pathological categories is presented. FADS provides easy diagnosis of shunts and tricuspid insufficiency. Quantitative information derived from the factors (cardiac output and mean transit time) were compared to those obtained by the region of interest method. Using FADS, a higher correlation with cardiac catheterization was found for cardiac output calculation. Thus compared to the ROI method, FADS presents obvious advantages: a good separation of overlapping cardiac chambers is obtained; this operator independant method provides more objective and reproducible results. A number of parameters of the cardio-pulmonary function can be assessed by first-pass radionuclide angiocardiography (RNA) [1,2]. Usually, they are calculated using time-activity curves (TAC) from regions of interest (ROI) drawn on the cardiac chambers and the lungs. This method has two main drawbacks: (1) the lack of inter and intra-observers reproducibility; (2) the problem of crosstalk which affects the evaluation of the cardio-pulmonary performance. The crosstalk on planar imaging is due to anatomical superimposition of the cardiac chambers and lungs. The activity measured in any ROI is the sum of the activity in several organs and 'decontamination' of the TAC cannot easily be performed using the ROI method [3]. Factor analysis of dynamic structures (FADS) [4,5] can solve the two problems mentioned above. It provides an automatic separation of anatomical structures according to their different temporal behaviour, even if they are superimposed. The resulting factors are estimates of the time evolution of the activity in each structure (underlying physiological components), and the associated factor images are estimates of the spatial distribution of each factor. The aim of this study was to assess the reliability of FADS in first pass RNA and compare the results to those obtained by the ROI method which is generally considered as the routine procedure.

Using a structural competency framework to teach structural racism in pre-health education.

PubMed

Metzl, Jonathan M; Petty, JuLeigh; Olowojoba, Oluwatunmise V

2018-02-01

The inclusion of structural competency training in pre-health undergraduate programs may offer significant benefits to future healthcare professionals. This paper presents the results of a comparative study of an interdisciplinary pre-health curriculum based in structural competency with a traditional premedical curriculum. The authors describe the interdisciplinary pre-health curriculum, titled Medicine, Health, and Society (MHS) at Vanderbilt University. The authors then use a new survey tool, the Structural Foundations of Health Survey, to evaluate structural skills and sensibilities. The analysis compares MHS majors (n = 185) with premed science majors (n = 63) and first-semester freshmen (n = 91), with particular attention to understanding how structural factors shape health. Research was conducted from August 2015 to December 2016. Results suggest that MHS majors identified and analyzed relationships between structural factors and health outcomes at higher rates and in deeper ways than did premed science majors and freshmen, and also demonstrated higher understanding of structural and implicit racism and health disparities. The skills that MHS students exhibited represent proficiencies increasingly stressed by the MCAT, the AAMC, and other educational bodies that emphasize how contextual factors shape expressions of health and illness. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

The factor structure of the illness attitude scales in a German population.

PubMed

Weck, Florian; Bleichhardt, Gaby; Hiller, Wolfgang

2009-01-01

The illness attitudes scales (IAS) were developed to identify different dimensions of hypochondrical attitudes, fears, beliefs, and abnormal illness behavior (Kellner 1986). Although there are several studies which focus on the scale structure of the IAS, the factor structure has not yet been made quite clear. Therefore, the aim of this study was to investigate the factor structure of the IAS on a large representative sample. Participants (N = 1,575) comparable with the general German population regarding sex, age, and education level completed the IAS. For the data analyses, a principal components analyses with subsequent oblique rotations was used. The minimum average partial method suggested a three-factor solution. The three factors were named (1) health anxiety, (2) health behavior, and (3) health habits. Internal consistency (Cronbach's alpha) for the three scales were (1) alpha = 0.88, (2) alpha = 0.75, and (3) alpha = 0.56. The results support previous findings, namely that the IAS factor structure appears to be less complex than originally suggested by the author. For a sample of the general German population, a three-factor solution fit best. Further items should be added to improve the internal consistency, especially for the third scale (health habits).

Factor Analysis of the Brazilian Version of UPPS Impulsive Behavior Scale

PubMed Central

Sediyama, Cristina Y. N.; Moura, Ricardo; Garcia, Marina S.; da Silva, Antonio G.; Soraggi, Carolina; Neves, Fernando S.; Albuquerque, Maicon R.; Whiteside, Setephen P.; Malloy-Diniz, Leandro F.

2017-01-01

Objective: To examine the internal consistency and factor structure of the Brazilian adaptation of the UPPS Impulsive Behavior Scale. Methods: UPPS is a self-report scale composed by 40 items assessing four factors of impulsivity: (a) urgency, (b) lack of premeditation; (c) lack of perseverance; (d) sensation seeking. In the present study 384 participants (278 women and 106 men), who were recruited from schools, universities, leisure centers and workplaces fulfilled the UPPS scale. An exploratory factor analysis was performed by using Varimax factor rotation and Kaiser Normalization, and we also conducted two confirmatory analyses to test the independency of the UPPS components found in previous analysis. Results: Results showed a decrease in mean UPPS total scores with age and this analysis showed that the youngest participants (below 30 years) scored significantly higher than the other groups over 30 years. No difference in gender was found. Cronbach’s alpha, results indicated satisfactory values for all subscales, with similar high values for the subscales and confirmatory factor analysis indexes also indicated a poor model fit. The results of two exploratory factor analysis were satisfactory. Conclusion: Our results showed that the Portuguese version has the same four-factor structure of the original and previous translations of the UPPS. PMID:28484414

The Experiences in Close Relationship Scale (ECR)-short form: reliability, validity, and factor structure.

PubMed

Wei, Meifen; Russell, Daniel W; Mallinckrodt, Brent; Vogel, David L

2007-04-01

We developed a 12-item, short form of the Experiences in Close Relationship Scale (ECR; Brennan, Clark, & Shaver, 1998) across 6 studies. In Study 1, we examined the reliability and factor structure of the measure. In Studies 2 and 3, we cross-validated the reliability, factor structure, and validity of the short form measure; whereas in Study 4, we examined test-retest reliability over a 1-month period. In Studies 5 and 6, we further assessed the reliability, factor structure, and validity of the short version of the ECR when administered as a stand-alone instrument. Confirmatory factor analyses indicated that 2 factors, labeled Anxiety and Avoidance, provided a good fit to the data after removing the influence of response sets. We found validity to be equivalent for the short and the original versions of the ECR across studies. Finally, the results were comparable when we embedded the short form within the original version of the ECR and when we administered it as a stand-alone measure.

The factor structure of the 12-item general health questionnaire (GHQ-12) in young Chinese civil servants.

PubMed

Liang, Ying; Wang, Lei; Yin, Xican

2016-09-26

The 12-item General Health Questionnaire (GHQ-12) is a commonly used screening instrument for measuring mental disorders. However, few studies have measured the mental health of Chinese professionals or explored the factor structure of the GHQ-12 through investigations of young Chinese civil servants. This study analyses the factor structure of the GHQ-12 on young Chinese civil servants. Respondents include 1051 participants from six cities in eastern China. Exploratory Factor Analysis (EFA) is used to identify the potential factor structure of the GHQ-12. Confirmatory Factor Analysis (CFA) models of previous studies are referred to for model fitting. The results indicate the GHQ-12 has very good reliability and validity. All ten CFA models are well fitted with the actual data. All the ten models are feasible and fit the data equally well. The Chinese version of the GHQ-12 is suitable for professional groups and can serve as a screening tool to detect anxiety and psychiatric disorders.

Factor analysis of Wechsler Adult Intelligence Scale-Revised in developmentally disabled persons.

PubMed

Di Nuovo, Santo F; Buono, Serafino

2006-12-01

The results of previous studies on the factorial structure of Wechsler Intelligence Scales are somewhat inconsistent across normal and pathological samples. To study specific clinical groups, such as developmentally disabled persons, it is useful to examine the factor structure in appropriate samples. A factor analysis was carried out using the principal component method and the Varimax orthogonal rotation on the Wechsler Adult Intelligence Scale (WAIS-R) in a sample of 203 developmentally disabled persons, with a mean age of 25 years 4 months. Developmental disability ranged from mild to moderate. Partially contrasting with previous studies on normal samples, results found a two-factor solution. Wechsler's traditional Verbal and Performance scales seems to be more appropriate for this sample than the alternative three-factor solution.

Structural Validity of the Life Regard Index

ERIC Educational Resources Information Center

Steger, Michael F.

2007-01-01

Counselors and researchers interested in examining meaning in life often use the Life Regard Index (LRI; J. Battista & R. Almond, 1973). In this study, confirmatory factor analyses (CFAs) of several factor models based on J. Battista & R. Almond's work failed to support the structural validity of the LRI. CFA results suggested an influence of…

Factor Structure of the WPPSI in Mental Health Clinic Settings.

ERIC Educational Resources Information Center

Haynes, Jack P.; Atkinson, David

1984-01-01

Factor-analyzed the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) scores of emotionally disturbed children (N=181). The results suggested that the structure of intelligence for emotionally disturbed children is similar to that for normal children. WPPSI profile analysis that uses subtest scores may be invalid in clinical settings.…

An Evaluation of the Psychache Scale on an Offender Population

ERIC Educational Resources Information Center

Mills, Jeremy F.; Green, Kate; Reddon, John R.

2005-01-01

This study examined the generalizability of a self-report measure of psychache to an offender population. The factor structure, construct validity, and criterion validity of the Psychache Scale was assessed on 136 male prison inmates. The results showed the Psychache Scale has a single underlying factor structure and to be strongly associated with…

WISC-R Factor Structures for Diagnosed Learning Disabled Navajo and Papago Children.

ERIC Educational Resources Information Center

Zarske, John A.; And Others

1981-01-01

Wechsler Intelligence Scale for Children (Revised) (WISC-R) factor structures were compared for learning disabled Navajo and Papago children. Results support the validity of the WISC-R as a measure of general intellectual functioning, and verbal and performance aspects for both groups, indicating its appropriateness for diverse groups of children.…

Exploring the Factor Structure of Neurocognitive Measures in Older Individuals

PubMed Central

Santos, Nadine Correia; Costa, Patrício Soares; Amorim, Liliana; Moreira, Pedro Silva; Cunha, Pedro; Cotter, Jorge; Sousa, Nuno

2015-01-01

Here we focus on factor analysis from a best practices point of view, by investigating the factor structure of neuropsychological tests and using the results obtained to illustrate on choosing a reasonable solution. The sample (n=1051 individuals) was randomly divided into two groups: one for exploratory factor analysis (EFA) and principal component analysis (PCA), to investigate the number of factors underlying the neurocognitive variables; the second to test the “best fit” model via confirmatory factor analysis (CFA). For the exploratory step, three extraction (maximum likelihood, principal axis factoring and principal components) and two rotation (orthogonal and oblique) methods were used. The analysis methodology allowed exploring how different cognitive/psychological tests correlated/discriminated between dimensions, indicating that to capture latent structures in similar sample sizes and measures, with approximately normal data distribution, reflective models with oblimin rotation might prove the most adequate. PMID:25880732

The structure of evaluative anxiety among children differing in socioeconomic status, ethnicity, and sex.

PubMed

Rhine, W R; Spaner, S D

1983-11-01

Following Anastasi and Thurstone, the factor structure of evaluative anxiety was examined among six groups of primary age boys and girls (N = 8064). A factor matching technique was used to study hypotheses about the effects of group differences in socioeconomic status (SES), ethnicity, and sex on the pattern of the children's responses to the Test Anxiety Scale for Children (TASC). Hypotheses about the congruence of factor patterns were based on both demographic differences and results of developmental research. The hypothesis of an SES X ethnicity X sex interaction was strongly supported. Implications for comparing factor structures, measuring evaluative anxiety, and future research of evaluative anxiety are discussed.

Factor structure of the Wechsler Intelligence Scale for Children-Fifth Edition: Exploratory factor analyses with the 16 primary and secondary subtests.

PubMed

Canivez, Gary L; Watkins, Marley W; Dombrowski, Stefan C

2016-08-01

The factor structure of the 16 Primary and Secondary subtests of the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V; Wechsler, 2014a) standardization sample was examined with exploratory factor analytic methods (EFA) not included in the WISC-V Technical and Interpretive Manual (Wechsler, 2014b). Factor extraction criteria suggested 1 to 4 factors and results favored 4 first-order factors. When this structure was transformed with the Schmid and Leiman (1957) orthogonalization procedure, the hierarchical g-factor accounted for large portions of total and common variance while the 4 first-order factors accounted for small portions of total and common variance; rendering interpretation at the factor index level less appropriate. Although the publisher favored a 5-factor model where the Perceptual Reasoning factor was split into separate Visual Spatial and Fluid Reasoning dimensions, no evidence for 5 factors was found. It was concluded that the WISC-V provides strong measurement of general intelligence and clinical interpretation should be primarily, if not exclusively, at that level. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

An examination of the structure of self-report psychopathy measures and their relations with general traits and externalizing behaviors.

PubMed

Seibert, L Alana; Miller, Joshua D; Few, Lauren R; Zeichner, Amos; Lynam, Donald R

2011-07-01

Self-report assessment of psychopathy is plagued by inconsistencies among the relations of the various psychopathy factors. We examined the factor structure of 3 prominent self-report measures of psychopathy-the Self-Report Psychopathy Scale-III (SRP-III; Williams, Paulhus, & Hare, 2007), the Levenson Self-Report Psychopathy Scale (LSRP; Levenson, Kiehl, & Fitzpatrick, 1995), and the Psychopathic Personality Inventory-R (PPI-R; Lilienfeld & Widows, 2005). A coherent 4-factor structure resulted from conducting an exploratory factor analysis (EFA) of the psychopathy subscales along with the domains from the five-factor model. Two of these factors were consistent with traditional conceptualizations of a 2-factor structure of psychopathy (i.e., Factor 1, which loaded negatively with Agreeableness; Factor 2, which loaded negatively with Conscientiousness), while 2 additional factors emerged, 1 of which emphasized low Neuroticism and 1 of which emphasized traits related to novelty/reward-seeking and dominance-related personality traits (high Extraversion). We also investigated the relations of these factors with a variety of externalizing behaviors (EB). The psychopathy scales indicative of interpersonal antagonism (i.e., Factor 1) were most consistently and strongly related to EB. Our findings are discussed in terms of the importance of a trait-based perspective in the assessment of psychopathy.

The Self-Description Inventory+, Part 1: Factor Structure and Convergent Validity Analyses

DTIC Science & Technology

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

[The Polish adaptation of the public speaking anxiety questionnaire].

PubMed

Chodkiewicz, Jan; Miniszewska, Joanna

2015-01-01

The aim of the study was the Polish adaptation of the shortened Public Speaking Anxiety Questionnaire GFER by Spitznagel and co-workers. GFER is a self-assessment method which consists of 16 statements and is designed to assess emotions, physiological reactions, and thoughts that appear in a situation of public speaking. GFER was used to examine 320 students from Lodz's universities. The State/Trait Anxiety Inventory - STAI by Spielberger, The Hospital Anxiety and Depression Scale by Zigmunt and Snaith and TCI by Cloninger were also used. The Polish version of GFER is a reliable and valid tool. The factor structure is similar to the original structure. As a result of the conducted analyses, there was obtained the 9-item version of the tool, which has a 2-factor structure - factor I: emotional and physiological reactions, factor II: worrying. The results obtained with GFER present a statistically significant correlation with other measures of anxiety and with the dimension of temperament: harm avoidance. The obtained results indicate that GFER may be used in both scientific research and therapeutic practice.

Confirmatory Factor and Rasch Analyses Support a Revised 14-Item Version of the Organizational, Policies, and Practices (OPP) Scale.

PubMed

Shi, Qiyun; MacDermid, Joy C; Tang, Kenneth; Sinden, Kathryn E; Walton, Dave; Grewal, Ruby

2017-06-01

Background The long version of the organizational, policies and practices (OPP) had a high burden and short versions were developed to solve this drawback. The 11-item version showed promise, but the ergonomic subscale was deficient. The OPP-14 was developed by adding three additional items to the ergonomics subscale. The aim of this study is to evaluate the factor structure using confirmatory factor and Rasch analyses in healthy firefighters. Methods A sample of 261 firefighters (Mean age 42 years, 95 % male) were sampled. A confirmatory factor and Rasch analyses were used to assess the internal consistency, factor structure and other psychometric characteristics of revised OPP-14. Results The OPP-14 demonstrates sound factor structure and internal consistency in firefighters. Confirmatory factor analysis confirmed the consistency of the original 4-domain structure (CFI = 0.97, TLI = 0.96, and RMSEA = 0.053). The 5 items showing misfit initially with disordered thresholds were rescored. The four subscales satisfied Rasch expectations with well target and acceptable reliability. Conclusions The OPP-14 scale shows a promising factor structure in this sample and remediated deficits found in OPP-11. This version may be preferable for musculoskeletal concerns or work applications where ergonomic indicators are relevant.

A descriptive study of patient satisfaction and the structural factors of Norwegian intensive care nursing.

PubMed

Johannessen, Gudrun; Eikeland, Anne; Stubberud, Dag-Gunnar; Fagerstöm, Lisbeth

2011-10-01

The aim of this study was to describe patient satisfaction with nursing care in three different Norwegian Coronary Intensive Care Units and compare the results with other structural factors such as nursing competence, skill-mix, clinical experience, nurse to patient ratio and number of beds. A descriptive and comparative design was employed and 150 patients at three Coronary Intensive Care Units were included. Patient satisfaction data was collected using the Intensive Nursing Care Quality Instrument (59 items). The data collected was comprised of two parts: a questionnaire and information on the structural factors of the organisational structure. The data was analysed using descriptive statistics. Patients expressed overall satisfaction with the nursing care. No clear association was found between patient satisfaction and nursing competence, skill-mix, clinical experience, nurse to patient ratio and number of beds. When comparing results between units, significant differences were seen for 17 out of 46 questions. The results provide insight into how critical care staffing and skill-mix affect patient satisfaction and guide future nursing research in this subject area. Copyright © 2011. Published by Elsevier Ltd.

Experiment study on RC frame retrofitted by the external structure

NASA Astrophysics Data System (ADS)

Liu, Chunyang; Shi, Junji; Hiroshi, Kuramoto; Taguchi, Takashi; Kamiya, Takashi

2016-09-01

A new retrofitting method is proposed herein for reinforced concrete (RC) structures through attachment of an external structure. The external structure consists of a fiber concrete encased steel frame, connection slab and transverse beams. The external structure is connected to the existing structure through a connection slab and transverse beams. Pseudostatic experiments were carried out on one unretrofitted specimen and three retrofitted frame specimens. The characteristics, including failure mode, crack pattern, hysteresis loops behavior, relationship of strain and displacement of the concrete slab, are demonstrated. The results show that the load carrying capacity is obviously increased, and the extension length of the slab and the number of columns within the external frame are important influence factors on the working performance of the existing structure. In addition, the displacement difference between the existing structure and the outer structure was caused mainly by three factors: shear deformation of the slab, extraction of transverse beams, and drift of the conjunction part between the slab and the existing frame. Furthermore, the total deformation determined by the first two factors accounted for approximately 80% of the damage, therefore these factors should be carefully considered in engineering practice to enhance the effects of this new retrofitting method.

Psychometric properties of the Brief Symptom Inventory-18 in a Spanish breast cancer sample.

PubMed

Galdón, Ma José; Durá, Estrella; Andreu, Yolanda; Ferrando, Maite; Murgui, Sergio; Pérez, Sandra; Ibañez, Elena

2008-12-01

The objective of this work was to study the psychometric and structural properties of the Brief Symptom Inventory-18 (BSI-18) in a sample of breast cancer patients (N=175). Confirmatory factor analyses were conducted. Two models were tested: the theoretical model with the original structure (three-dimensional), and the empirical model (a four-factor structure) obtained through exploratory factor analysis initially performed by the authors of the BSI-18. The eligible structure was the original proposal consisting of three dimensions: somatization, depression, and anxiety scores. These measures also showed good internal consistency. The results of this study support the reliability and structural validity of the BSI-18 as a standardized instrument for screening purposes in breast cancer patients, with the added benefits of simplicity and ease of application.

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study

PubMed Central

Rönnberg, Jerker; Lunner, Thomas; Ng, Elaine Hoi Ning; Lidestam, Björn; Zekveld, Adriana Agatha; Sörqvist, Patrik; Lyxell, Björn; Träff, Ulf; Yumba, Wycliffe; Classon, Elisabet; Hällgren, Mathias; Larsby, Birgitta; Signoret, Carine; Pichora-Fuller, M. Kathleen; Rudner, Mary; Danielsson, Henrik; Stenfelt, Stefan

2016-01-01

Abstract Objective: The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Study sample: Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. Design: LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. Results: The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R2 = 0.40). Conclusions: All LEVEL 2 factors are important theoretically as well as for clinical assessment. PMID:27589015

The utility of the bifactor model in understanding unique components of anxiety sensitivity in a South Korean sample.

PubMed

Ebesutani, Chad; Kim, Mirihae; Park, Hee-Hoon

2016-08-01

The present study was the first to examine the applicability of the bifactor structure underlying the Anxiety Sensitivity Index-3 (ASI-3) in an East Asian (South Korean) sample and to determine which factors in the bifactor model were significantly associated with anxiety, depression, and negative affect. Using a sample of 289 South Korean university students, we compared (a) the original 3-factor AS model, (b) a 3-group bifactor AS model, and (c) a 2-group bifactor AS model (with only the physical and social concern group factors present). Results revealed that the 2-group bifactor AS model fit the ASI-3 data the best. Relatedly, although all ASI-3 items loaded on the general AS factor, the Cognitive Concern group factor was not defined in the bifactor model and may therefore need to be omitted in order to accurately model AS when conducting factor analysis and structural equation modeling (SEM) in cross cultural contexts. SEM results also revealed that the general AS factor was the only factor from the 2-group bifactor model that significantly predicted anxiety, depression, and negative affect. Implications and importance of this new bifactor structure of Anxiety Sensitivity in East Asian samples are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Factor Structure of the Psychopathic Personality Inventory (PPI): Findings from a Large Incarcerated Sample

PubMed Central

Neumann, Craig S.; Malterer, Melanie B.; Newman, Joseph P.

2010-01-01

Recent exploratory factor analysis (EFA) of the Psychopathic Personality Inventory (PPI; Lilienfeld, 1990) with a community sample suggested that the PPI subscales may be comprised of two higher-order factors (Benning et al., 2003). However, little research has examined the PPI structure in offenders. The current study attempted to replicate the Benning et al. two-factor solution using a large (N=1224) incarcerated male sample. Confirmatory factor analysis (CFA) of this model with the full sample resulted in poor model fit. Next, to identify a factor solution that would summarize the offender data, EFA was conducted using a split-half of the total sample, followed by an attempt to replicate the EFA solution via CFA with the other split-half sample. Using the recommendations of Prooijen and van der Kloot (2001) for recovering EFA solutions, model fit results provided some evidence that the EFA solution could be recovered via CFA. However, this model involved extensive cross-loadings of the subscales across three factors, suggesting item overlap across PPI subscales. In sum, the two-factor solution reported by Benning et al. (2003) was not a viable model for the current sample of offenders, and additional research is needed to elucidate the latent structure of the PPI. PMID:18557694

The structure of Turkish trait-descriptive adjectives.

PubMed

Somer, O; Goldberg, L R

1999-03-01

This description of the Turkish lexical project reports some initial findings on the structure of Turkish personality-related variables. In addition, it provides evidence on the effects of target evaluative homogeneity vs. heterogeneity (e.g., samples of well-liked target individuals vs. samples of both liked and disliked targets) on the resulting factor structures, and thus it provides a first test of the conclusions reached by D. Peabody and L. R. Goldberg (1989) using English trait terms. In 2 separate studies, and in 2 types of data sets, clear versions of the Big Five factor structure were found. And both studies replicated and extended the findings of Peabody and Goldberg; virtually orthogonal factors of relatively equal size were found in the homogeneous samples, and a more highly correlated set of factors with relatively large Agreeableness and Conscientiousness dimensions was found in the heterogeneous samples.

The Structure of the Chinese Material Value Scale: An Eastern Cultural View

PubMed Central

Liao, Jiangqun; Wang, Lei

2017-01-01

This study investigated the structure of the Chinese Material Value Scale (MVS). A two-factor structure, rather than the original three-factor structure, was proposed for China by means of confirmatory factor analysis. Direct evidence showed that the dimensions of success and happiness could be merged together. Both explicit and implicit methods were used to examine the relationship between success and happiness based on possession. In particular, as an implicit method, the dot-probe paradigm recording participants’ response time supported the idea that the two-factors could be merged together. The results also showed that for Chinese people, success to an extent means happiness, while the converse is not necessarily true. Chinese are much more concerned about social evaluation than their own feelings, and this cultural characteristic is reflected in our findings. PMID:29163258

Factor structure of the Japanese version of the Edinburgh Postnatal Depression Scale in the postpartum period.

PubMed

Kubota, Chika; Okada, Takashi; Aleksic, Branko; Nakamura, Yukako; Kunimoto, Shohko; Morikawa, Mako; Shiino, Tomoko; Tamaji, Ai; Ohoka, Harue; Banno, Naomi; Morita, Tokiko; Murase, Satomi; Goto, Setsuko; Kanai, Atsuko; Masuda, Tomoko; Ando, Masahiko; Ozaki, Norio

2014-01-01

The Edinburgh Postnatal Depression Scale (EPDS) is a widely used screening tool for postpartum depression (PPD). Although the reliability and validity of EPDS in Japanese has been confirmed and the prevalence of PPD is found to be about the same as Western countries, the factor structure of the Japanese version of EPDS has not been elucidated yet. 690 Japanese mothers completed all items of the EPDS at 1 month postpartum. We divided them randomly into two sample sets. The first sample set (n = 345) was used for exploratory factor analysis, and the second sample set was used (n = 345) for confirmatory factor analysis. The result of exploratory factor analysis indicated a three-factor model consisting of anxiety, depression and anhedonia. The results of confirmatory factor analysis suggested that the anxiety and anhedonia factors existed for EPDS in a sample of Japanese women at 1 month postpartum. The depression factor varies by the models of acceptable fit. We examined EPDS scores. As a result, "anxiety" and "anhedonia" exist for EPDS among postpartum women in Japan as already reported in Western countries. Cross-cultural research is needed for future research.

A COMBINED FACTOR ANALYSIS OF CREATIVITY AND INTELLIGENCE.

PubMed

Cave, R L

1970-04-01

A battery of tests was given to 447 studenits in the secondary schools of Alcoa, Tennessee. The tests were composed of the Lorge-Thorndike Intelligence Tests, and five selected creativity tests. The combined battery of tests was factor analyzed and rotated to an oblique simple structure, and then to a hierachical solution. Three factors were found: the verbal intelligence and reasoning factors identified in many previous studies, and a creativity faotor. The structure was very oblique. The second order factor, g, was found to count for 77% of the variance of the verbal facbor, 89% of the reasoning factor and 48% of the creativity factor. These results were compared with those of previous studies of creativity and intelligence.

A Confirmatory Factor Analysis of the Structure of Statistics Anxiety Measure: An examination of four alternative models

PubMed Central

Vahedi, Shahram; Farrokhi, Farahman

2011-01-01

Objective The aim of this study is to explore the confirmatory factor analysis results of the Persian adaptation of Statistics Anxiety Measure (SAM), proposed by Earp. Method The validity and reliability assessments of the scale were performed on 298 college students chosen randomly from Tabriz University in Iran. Confirmatory factor analysis (CFA) was carried out to determine the factor structures of the Persian adaptation of SAM. Results As expected, the second order model provided a better fit to the data than the three alternative models. Conclusions Hence, SAM provides an equally valid measure for use among college students. The study both expands and adds support to the existing body of math anxiety literature. PMID:22952530

Factorial Structure and Age-Related Psychometrics of the MIDUS Personality Adjective Items across the Lifespan

PubMed Central

Zimprich, Daniel; Allemand, Mathias; Lachman, Margie E.

2014-01-01

The present study addresses issues of measurement invariance and comparability of factor parameters of Big Five personality adjective items across age. Data from the Midlife in the United States (MIDUS) survey were used to investigate age-related developmental psychometrics of the MIDUS personality adjective items in two large cross-sectional samples (exploratory sample: N = 862; analysis sample: N = 3,000). After having established and replicated a comprehensive five-factor structure of the measure, increasing levels of measurement invariance were tested across ten age groups. Results indicate that the measure demonstrates strict measurement invariance in terms of number of factors and factor loadings. Also, we found that factor variances and covariances were equal across age groups. By contrast, a number of age-related factor mean differences emerged. The practical implications of these results are discussed and future research is suggested. PMID:21910548

Factorial Structure of Rosenberg's Self-Esteem Scale among Crack-Cocaine Drug Users.

ERIC Educational Resources Information Center

Wang, Jichuan; Siegal, Harvey A.; Falck, Russell S.; Carlson, Robert G.

2001-01-01

Used nine different confirmatory factor analysis models to test the factorial structure of Rosenberg's (M. Rosenberg, 1965) self-esteem scale with a sample of 430 crack-cocaine users. Results partly support earlier research to show a single global self-esteem factor underlying responses to the Rosenberg scale, method effects associated with item…

The Psychometric Properties of the Inventory of Callous-Unemotional Traits in an Undergraduate Sample

ERIC Educational Resources Information Center

Kimonis, Eva R.; Branch, Jessica; Hagman, Brett; Graham, Nicole; Miller, Cailey

2013-01-01

In the present study, the psychometric properties and factor structure of the 24-item Inventory of Callous-Unemotional Traits (ICU) were tested in a sample of 687 college students. Results support a similar 3-factor structure to that identified in samples of youths, in whom this measure was previously validated. Correlations with external…

Evidence of Second-Order Factor Structure in a Diagnostic Problem Space: Implications for Medical Education.

ERIC Educational Resources Information Center

Papa, Frank J.; And Others

1997-01-01

Chest pain was identified as a specific medical problem space, and disease classes were modeled to define it. Results from a test taken by 628 medical residents indicate a second-order factor structure that suggests that chest pain is a multidimensional problem space. Implications for medical education are discussed. (SLD)

Factor Structure of the DSM-IV Criteria for College Students Using the Adult Behavior Checklist.

ERIC Educational Resources Information Center

Johnson, Brian D.; Smith, Everett V., Jr.

1998-01-01

The factor structure of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-IV) criteria for attention deficit hyperactivity disorder (ADHD) is evaluated in a sample of 1,503 college students. The Adult Behavior Checklist is evaluated as a screening instrument. Results support the extension of ADHD criteria for diagnosis to college…

The Work Role Functioning Questionnaire v2.0 Showed Consistent Factor Structure Across Six Working Samples.

PubMed

Abma, Femke I; Bültmann, Ute; Amick Iii, Benjamin C; Arends, Iris; Dorland, Heleen F; Flach, Peter A; van der Klink, Jac J L; van de Ven, Hardy A; Bjørner, Jakob Bue

2017-09-09

Objective The Work Role Functioning Questionnaire v2.0 (WRFQ) is an outcome measure linking a persons' health to the ability to meet work demands in the twenty-first century. We aimed to examine the construct validity of the WRFQ in a heterogeneous set of working samples in the Netherlands with mixed clinical conditions and job types to evaluate the comparability of the scale structure. Methods Confirmatory factor and multi-group analyses were conducted in six cross-sectional working samples (total N = 2433) to evaluate and compare a five-factor model structure of the WRFQ (work scheduling demands, output demands, physical demands, mental and social demands, and flexibility demands). Model fit indices were calculated based on RMSEA ≤ 0.08 and CFI ≥ 0.95. After fitting the five-factor model, the multidimensional structure of the instrument was evaluated across samples using a second order factor model. Results The factor structure was robust across samples and a multi-group model had adequate fit (RMSEA = 0.63, CFI = 0.972). In sample specific analyses, minor modifications were necessary in three samples (final RMSEA 0.055-0.080, final CFI between 0.955 and 0.989). Applying the previous first order specifications, a second order factor model had adequate fit in all samples. Conclusion A five-factor model of the WRFQ showed consistent structural validity across samples. A second order factor model showed adequate fit, but the second order factor loadings varied across samples. Therefore subscale scores are recommended to compare across different clinical and working samples.

Gray Matter and Intelligence Factors: Is There a Neuro-g?

ERIC Educational Resources Information Center

Haier, Richard J.; Colom, Roberto; Schroeder, David H.; Condon, Christopher A.; Tang, Cheuk; Eaves, Emily; Head, Kevin

2009-01-01

Heterogeneous results among neuro-imaging studies using psychometric intelligence measures may result from the variety of tests used. The g-factor may provide a common metric across studies. Here we derived a g-factor from a battery of eight cognitive tests completed by 6929 young adults, 40 of whom also completed structural MRI scans. Regional…

Validation of the Social Appearance Anxiety Scale: factor, convergent, and divergent validity.

PubMed

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.

Is the Dissociative Experiences Scale able to identify detachment and compartmentalization symptoms? Factor structure of the Dissociative Experiences Scale in a large sample of psychiatric and nonpsychiatric subjects.

PubMed

Mazzotti, Eva; Farina, Benedetto; Imperatori, Claudio; Mansutti, Federica; Prunetti, Elena; Speranza, Anna Maria; Barbaranelli, Claudio

2016-01-01

In this study, we explored the ability of the Dissociative Experiences Scale (DES) to catch detachment and compartmentalization symptoms. The DES factor structure was evaluated in 768 psychiatric patients (546 women and 222 men) and in 2,403 subjects enrolled in nonpsychiatric settings (1,857 women and 546 men). All participants were administered the Italian version of DES. Twenty senior psychiatric experts in the treatment of dissociative symptoms independently assessed the DES items and categorized each of them as follows: "C" for compartmentalization, "D" for detachment, and "NC" for noncongruence with either C or D. Confirmatory factor analysis supported the three-factor structure of DES in both clinical and nonclinical samples and its invariance across the two groups. Moreover, factor analyses results overlapped with those from the expert classification procedure. Our results showed that DES can be used as a valid instrument for clinicians to assess the frequency of different types of dissociative experiences including detachment and compartmentalization.

Psychometric properties and Confirmatory structure of the Strengths and difficulties questionnaire in a sample of adolescents in Nigeria.

PubMed

Akpa, Onoja M; Afolabi, Rotimi F; Fowobaje, Kayode R

Though the SDQ has been used in selected studies in Nigeria, its theoretical structure has not been fully and appropriately investigated in the setting. The present study employs Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) to investigate the theoretical structure of the self-reported version of the SDQ in a sample of adolescents in Benue state, Nigeria. A total of 1,244 adolescents from different categories of secondary schools in Makurdi and Vandekya Local government areas of Benue state participated in the study. Preliminary data analyses were performed using descriptive statistics while the theoretical structure of the SDQ was assessed using EFA and CFA. Model fits were assessed using Chi-square test and other fit indices at 5% significance level. Participants were 14.19±2.45 (Vandekya) and 14.19±2.45 (Makurdi) years old. Results of the EFA and CFA revealed a 3-factor oblique model as the best model for the sample of adolescents studied ( χ 2 / df =2.20, p<0.001) with all fit indices yielding better results. A correlated 3-factor model fits the present data better than the 5-factor theoretical model of the SDQ. The use of the original 5-factor model of the SDQ in the present setting should be interpreted with caution.

Optimization of structures on the basis of fracture mechanics and reliability criteria

NASA Technical Reports Server (NTRS)

Heer, E.; Yang, J. N.

1973-01-01

Systematic summary of factors which are involved in optimization of given structural configuration is part of report resulting from study of analysis of objective function. Predicted reliability of performance of finished structure is sharply dependent upon results of coupon tests. Optimization analysis developed by study also involves expected cost of proof testing.

Investigation of the factor structure of spirituality and religiosity in Iranian Shiite university students.

PubMed

Joshanloo, Mohsen

2012-01-01

One of the important challenges facing psychologists of religion pertains to the definition of religiosity and spirituality. One way of understanding the connection between these two concepts is to suppose that one of them is a subset of the other. Another useful and sensitive way, however, is to view spirituality and religiosity as overlapping constructs, sharing some characteristics but also retaining nonshared features. Empirical studies examining the factor structure of spirituality and religiosity are scant and almost all of them come from Western culture. These factor analytic studies generally confirm that religiosity and spirituality can best be described in terms of two distinct yet correlated factors. To date, no study has investigated the relationship between these two constructs in Islamic cultures. To redress this imbalance, confirmatory factor analysis was used to examine the factor structure of religiosity and spirituality in two Iranian Shiite samples using an extensive set of scales (including Santa Clara Strength of Religious Faith, Spiritual Involvement and Beliefs Scale - Revised, Spiritual Meaning Scale, and Spiritual Transcendence Scale). Two hypothetical models were tested: a model that viewed spirituality and religiosity as correlated but separate constructs and a model that combined the indicators of religiosity and spirituality into a single construct. In keeping with the results obtained in Western cultures, results of confirmatory factor analyses, conducted in Study 1 (N=225) and Study 2 (N=288), revealed that a two-factor model fitted the data better than a single-factor model. Implications of the results are discussed, as are study limitations and directions for further research.

Exploring the measurement structure of the Gambling Related Cognitions Scale (GRCS) in treatment-seekers: A Bayesian structural equation modelling approach.

PubMed

Smith, David; Woodman, Richard; Drummond, Aaron; Battersby, Malcolm

2016-03-30

Knowledge of a problem gambler's underlying gambling related cognitions plays an important role in treatment planning. The Gambling Related Cognitions Scale (GRCS) is therefore frequently used in clinical settings for screening and evaluation of treatment outcomes. However, GRCS validation studies have generated conflicting results regarding its latent structure using traditional confirmatory factor analyses (CFA). This may partly be due to the rigid constraints imposed on cross-factor loadings with traditional CFA. The aim of this investigation was to determine whether a Bayesian structural equation modelling (BSEM) approach to examination of the GRCS factor structure would better replicate substantive theory and also inform model re-specifications. Participants were 454 treatment-seekers at first presentation to a gambling treatment centre between January 2012 and December 2014. Model fit indices were well below acceptable standards for CFA. In contrast, the BSEM model which included small informative priors for the residual covariance matrix in addition to cross-loadings produced excellent model fit for the original hypothesised factor structure. The results also informed re-specification of the CFA model which provided more reasonable model fit. These conclusions have implications that should be useful to both clinicians and researchers evaluating measurement models relating to gambling related cognitions in treatment-seekers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Factorial invariance of posttraumatic stress disorder symptoms across three veteran samples.

PubMed

McDonald, Scott D; Beckham, Jean C; Morey, Rajendra; Marx, Christine; Tupler, Larry A; Calhoun, Patrick S

2008-06-01

Research generally supports a 4-factor structure of posttraumatic stress disorder (PTSD) symptoms. However, few studies have established factor invariance by comparing multiple groups. This study examined PTSD symptom structure using the Davidson Trauma Scale (DTS) across three veteran samples: treatment-seeking Vietnam-era veterans, treatment-seeking post-Vietnam-era veterans, and Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) veteran research participants. Confirmatory factor analyses of DTS items demonstrated that a 4-factor structural model of the DTS (reexperiencing, avoidance, numbing, and hyperarousal) was superior to five alternate models, including the conventional 3-factor model proposed by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; American Psychiatric Association, 1994). Results supported factor invariance across the three veteran cohorts, suggesting that cross-group comparisons are interpretable. Implications and applications for DSM-IV nosology and the validity of symptom measures are discussed.

Structural and incremental validity of the Wechsler Adult Intelligence Scale-Fourth Edition with a clinical sample.

PubMed

Nelson, Jason M; Canivez, Gary L; Watkins, Marley W

2013-06-01

Structural and incremental validity of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV; Wechsler, 2008a) was examined with a sample of 300 individuals referred for evaluation at a university-based clinic. Confirmatory factor analysis indicated that the WAIS-IV structure was best represented by 4 first-order factors as well as a general intelligence factor in a direct hierarchical model. The general intelligence factor accounted for the most common and total variance among the subtests. Incremental validity analyses indicated that the Full Scale IQ (FSIQ) generally accounted for medium to large portions of academic achievement variance. For all measures of academic achievement, the first-order factors combined accounted for significant achievement variance beyond that accounted for by the FSIQ, but individual factor index scores contributed trivial amounts of achievement variance. Implications for interpreting WAIS-IV results are discussed. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Evolutionary profiles derived from the QR factorization of multiple structural alignments gives an economy of information.

PubMed

O'Donoghue, Patrick; Luthey-Schulten, Zaida

2005-02-25

We present a new algorithm, based on the multidimensional QR factorization, to remove redundancy from a multiple structural alignment by choosing representative protein structures that best preserve the phylogenetic tree topology of the homologous group. The classical QR factorization with pivoting, developed as a fast numerical solution to eigenvalue and linear least-squares problems of the form Ax=b, was designed to re-order the columns of A by increasing linear dependence. Removing the most linear dependent columns from A leads to the formation of a minimal basis set which well spans the phase space of the problem at hand. By recasting the problem of redundancy in multiple structural alignments into this framework, in which the matrix A now describes the multiple alignment, we adapted the QR factorization to produce a minimal basis set of protein structures which best spans the evolutionary (phase) space. The non-redundant and representative profiles obtained from this procedure, termed evolutionary profiles, are shown in initial results to outperform well-tested profiles in homology detection searches over a large sequence database. A measure of structural similarity between homologous proteins, Q(H), is presented. By properly accounting for the effect and presence of gaps, a phylogenetic tree computed using this metric is shown to be congruent with the maximum-likelihood sequence-based phylogeny. The results indicate that evolutionary information is indeed recoverable from the comparative analysis of protein structure alone. Applications of the QR ordering and this structural similarity metric to analyze the evolution of structure among key, universally distributed proteins involved in translation, and to the selection of representatives from an ensemble of NMR structures are also discussed.

Exploring the hierarchical structure of the MMPI-2-RF Personality Psychopathology Five in psychiatric patient and university student samples.

PubMed

Bagby, R Michael; Sellbom, Martin; Ayearst, Lindsay E; Chmielewski, Michael S; Anderson, Jaime L; Quilty, Lena C

2014-01-01

In this study our goal was to examine the hierarchical structure of personality pathology as conceptualized by Harkness and McNulty's (1994) Personality Psychopathology Five (PSY-5) model, as recently operationalized by the MMPI-2-RF (Ben-Porath & Tellegen, 2011) PSY-5r scales. We used Goldberg's (2006) "bass-ackwards" method to obtain factor structure using PSY-5r item data, successively extracting from 1 to 5 factors in a sample of psychiatric patients (n = 1,000) and a sample of university undergraduate students (n = 1,331). Participants from these samples had completed either the MMPI-2 or the MMPI-2-RF. The results were mostly consistent across the 2 samples, with some differences at the 3-factor level. In the patient sample a factor structure representing 3 broad psychopathology domains (internalizing, externalizing, and psychoticism) emerged; in the student sample the 3-factor level represented what is more commonly observed in "normal-range" personality models (negative emotionality, introversion, and disconstraint). At the 5-factor level the basic structure was similar across the 2 samples and represented well the PSY-5r domains.

Determinants of community structure of zooplankton in heavily polluted river ecosystems

NASA Astrophysics Data System (ADS)

Xiong, Wei; Li, Jie; Chen, Yiyong; Shan, Baoqing; Wang, Weimin; Zhan, Aibin

2016-02-01

River ecosystems are among the most affected habitats globally by human activities, such as the release of chemical pollutants. However, it remains largely unknown how and to what extent many communities such as zooplankton are affected by these environmental stressors in river ecosystems. Here, we aim to determine major factors responsible for shaping community structure of zooplankton in heavily polluted river ecosystems. Specially, we use rotifers in the Haihe River Basin (HRB) in North China as a case study to test the hypothesis that species sorting (i.e. species are “filtered” by environmental factors and occur at environmental suitable sites) plays a key role in determining community structure at the basin level. Based on an analysis of 94 sites across the plain region of HRB, we found evidence that both local and regional factors could affect rotifer community structure. Interestingly, further analyses indicated that local factors played a more important role in determining community structure. Thus, our results support the species sorting hypothesis in highly polluted rivers, suggesting that local environmental constraints, such as environmental pollution caused by human activities, can be stronger than dispersal limitation caused by regional factors to shape local community structure of zooplankton at the basin level.

Contributions of historical and contemporary geographic and environmental factors to phylogeographic structure in a Tertiary relict species, Emmenopterys henryi (Rubiaceae)

PubMed Central

Zhang, Yong-Hua; Wang, Ian J.; Comes, Hans Peter; Peng, Hua; Qiu, Ying-Xiong

2016-01-01

Examining how historical and contemporary geographic and environmental factors contribute to genetic divergence at different evolutionary scales is a central yet largely unexplored question in ecology and evolution. Here, we examine this key question by investigating how environmental and geographic factors across different epochs have driven genetic divergence at deeper (phylogeographic) and shallower (landscape genetic) evolutionary scales in the Chinese Tertiary relict tree Emmenopterys henryi. We found that geography played a predominant role at all levels – phylogeographic clades are broadly geographically structured, the deepest levels of divergence are associated with major geological or pre-Quaternary climatic events, and isolation by distance (IBD) primarily explained population genetic structure. However, environmental factors are clearly also important – climatic fluctuations since the Last Interglacial (LIG) have likely contributed to phylogeographic structure, and the population genetic structure (in our AFLP dataset) was partly explained by isolation by environment (IBE), which may have resulted from natural selection in environments with divergent climates. Thus, historical and contemporary geography and historical and contemporary environments have all shaped patterns of genetic structure in E. henryi, and, in fact, changes in the landscape through time have also been critical factors. PMID:27137438

Contributions of historical and contemporary geographic and environmental factors to phylogeographic structure in a Tertiary relict species, Emmenopterys henryi (Rubiaceae).

PubMed

Zhang, Yong-Hua; Wang, Ian J; Comes, Hans Peter; Peng, Hua; Qiu, Ying-Xiong

2016-05-03

Examining how historical and contemporary geographic and environmental factors contribute to genetic divergence at different evolutionary scales is a central yet largely unexplored question in ecology and evolution. Here, we examine this key question by investigating how environmental and geographic factors across different epochs have driven genetic divergence at deeper (phylogeographic) and shallower (landscape genetic) evolutionary scales in the Chinese Tertiary relict tree Emmenopterys henryi. We found that geography played a predominant role at all levels - phylogeographic clades are broadly geographically structured, the deepest levels of divergence are associated with major geological or pre-Quaternary climatic events, and isolation by distance (IBD) primarily explained population genetic structure. However, environmental factors are clearly also important - climatic fluctuations since the Last Interglacial (LIG) have likely contributed to phylogeographic structure, and the population genetic structure (in our AFLP dataset) was partly explained by isolation by environment (IBE), which may have resulted from natural selection in environments with divergent climates. Thus, historical and contemporary geography and historical and contemporary environments have all shaped patterns of genetic structure in E. henryi, and, in fact, changes in the landscape through time have also been critical factors.

Psychometric Evaluation of the Eating Disorder Examination-Questionnaire for Bariatric Surgery Candidates

PubMed Central

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

A tight and explicit representation of Q in sparse QR factorization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ng, E.G.; Peyton, B.W.

1992-05-01

In QR factorization of a sparse m{times}n matrix A (m {ge} n) the orthogonal factor Q is often stored implicitly as a lower trapezoidal matrix H known as the Householder matrix. This paper presents a simple characterization of the row structure of Q, which could be used as the basis for a sparse data structure that can store Q explicitly. The new characterization is a simple extension of a well known row-oriented characterization of the structure of H. Hare, Johnson, Olesky, and van den Driessche have recently provided a complete sparsity analysis of the QR factorization. Let U be themore » matrix consisting of the first n columns of Q. Using results from, we show that the data structures for H and U resulting from our characterizations are tight when A is a strong Hall matrix. We also show that H and the lower trapezoidal part of U have the same sparsity characterization when A is strong Hall. We then show that this characterization can be extended to any weak Hall matrix that has been permuted into block upper triangular form. Finally, we show that permuting to block triangular form never increases the fill incurred during the factorization.« less

Sensitivity study on durability variables of marine concrete structures

NASA Astrophysics Data System (ADS)

Zhou, Xin'gang; Li, Kefei

2013-06-01

In order to study the influence of parameters on durability of marine concrete structures, the parameter's sensitivity analysis was studied in this paper. With the Fick's 2nd law of diffusion and the deterministic sensitivity analysis method (DSA), the sensitivity factors of apparent surface chloride content, apparent chloride diffusion coefficient and its time dependent attenuation factor were analyzed. The results of the analysis show that the impact of design variables on concrete durability was different. The values of sensitivity factor of chloride diffusion coefficient and its time dependent attenuation factor were higher than others. Relative less error in chloride diffusion coefficient and its time dependent attenuation coefficient induces a bigger error in concrete durability design and life prediction. According to probability sensitivity analysis (PSA), the influence of mean value and variance of concrete durability design variables on the durability failure probability was studied. The results of the study provide quantitative measures of the importance of concrete durability design and life prediction variables. It was concluded that the chloride diffusion coefficient and its time dependent attenuation factor have more influence on the reliability of marine concrete structural durability. In durability design and life prediction of marine concrete structures, it was very important to reduce the measure and statistic error of durability design variables.

Life satisfaction and self-reported problems after spinal cord injury: measurement of underlying dimensions.

PubMed

Krause, James S; Reed, Karla S

2009-08-01

Evaluate the utility of the current 7-scale structure of the Life Situation Questionnaire-Revised (LSQ-R) using confirmatory factor analysis (CFA) and explore the factor structure of each set of items. Adults (N = 1,543) with traumatic spinal cord injury (SCI) were administered the 20 satisfaction and 30 problems items from the LSQ-R. CFA suggests that the existing 7-scale structure across the 50 items was within the acceptable range (root-mean-square error of approximation [RMSEA] = 0.078), although it fell just outside of this range for women. Factor analysis revealed 3 satisfaction factors and 6 problems factors. The overall fit of the problems items (RMSEA = 0.070) was superior to that of the satisfaction items (RMSEA = 0.80). RMSEA fell just outside of the acceptable range for Whites and men on the satisfaction scales. All scales had acceptable internal consistency. Results suggest the original scoring of the LSQ-R remains viable, although individual results should be reviewed for special population. Factor analysis of subsets of items allows satisfaction and problems items to be used independently, depending on the study purpose. (c) 2009 APA

Exploring Individual and Structural Factors Associated with Employment Among Young Transgender Women of Color Using a No-Cost Transgender Legal Resource Center

PubMed Central

Hill, Brandon J.; Rosentel, Kris; Bak, Trevor; Silverman, Michael; Crosby, Richard; Salazar, Laura; Kipke, Michele

2017-01-01

Abstract Purpose: The purpose of this study was to explore individual and structural factors associated with employment among young transgender women (TW) of color. Methods: Sixty-five trans women of color were recruited from the Transgender Legal Defense and Education Fund to complete a 30-min interviewer-assisted survey assessing sociodemographics, housing, workplace discrimination, job-seeking self-efficacy, self-esteem, perceived public passability, and transactional sex work. Results: Logistic regression models revealed that stable housing (structural factor) and job-seeking self-efficacy (individual factor) were significantly associated with currently being employed. Conclusion: Our findings underscore the need for multilevel approaches to assist TW of color gain employment. PMID:28795154

Measuring Alexithymia via Trait Approach-I: A Alexithymia Scale Item Selection and Formation of Factor Structure

PubMed Central

TATAR, Arkun; SALTUKOĞLU, Gaye; ALİOĞLU, Seda; ÇİMEN, Sümeyye; GÜVEN, Hülya; AY, Çağla Ebru

2017-01-01

Introduction It is not clear in the literature whether available instruments are sufficient to measure alexithymia because of its theoretical structure. Moreover, it has been reported that several measuring instruments are needed to measure this construct, and all the instruments have different error sources. The old and the new forms of Toronto Alexithymia Scale are the only instruments available in Turkish. Thus, the purpose of this study was to develop a new scale to measure alexithymia, selecting items and constructing the factor structure. Methods A total of 1117 patients aged from 19 to 82 years (mean = 35.05 years) were included. A 100-item pool was prepared and applied to 628 women and 489 men. Data were analyzed using Explanatory Factor Analysis, Confirmatory Factor Analysis, and Item Response Theory and 28 items were selected. The new form of 28 items was applied to 415 university students, including 271 women and 144 men aged from 18 to 30 (mean=21.44). Results The results of Explanatory Factor Analysis revealed a five-factor construct of “Solving and Expressing Affective Experiences,” “External Locused Cognitive Style,” “Tendency to Somatize Affections,” “Imaginary Life and Visualization,” and “Acting Impulsively,” along with a two-factor construct representing the “Affective” and “Cognitive” components. All the components of the construct showed good model fit and high internal consistency. The new form was tested in terms of internal consistency, test-retest reliability, and concurrent validity using Toronto Alexithymia Scale as criteria and discriminative validity using Five-Factor Personality Inventory Short Form. Conclusion The results showed that the new scale met the basic psychometric requirements. Results have been discussed in line with related studies. PMID:29033633

Reassessment of the Psychometric Characteristics and Factor Structure of the ‘Perceived Stress Questionnaire’ (PSQ): Analysis in a Sample of Dental Students

PubMed Central

Montero-Marin, Jesús; Piva Demarzo, Marcelo Marcos; Pereira, Joao Paulo; Olea, Marina; García-Campayo, Javier

2014-01-01

Background The training to become a dentist can create psychological distress. The present study evaluates the structure of the ‘Perceived Stress Questionnaire’ (PSQ), its internal consistency model and interrelatedness with burnout, anxiety, depression and resilience among dental students. Methods The study employed a cross-sectional design. A sample of Spanish dental students (n = 314) completed the PSQ, the ‘Goldberg Anxiety and Depression Scale’ (GADS), ‘Connor-Davidson Resilience Scale’ (10-item CD-RISC) and ‘Maslach Burnout Inventory-Student Survey’ (MBI-SS). The structure was estimated using Parallel Analysis from polychoric correlations. Unweighted Least Squares was the method for factor extraction, using the Item Response Theory to evaluate the discriminative power of items. Internal consistency was assessed by squaring the correlation between the latent true variable and the observed variable. The relationships between the PSQ and the other constructs were analysed using Spearman’s coefficient. Results The results showed a PSQ structure through two sub-factors (‘frustration’ and ‘tenseness’) with regard to one general factor (‘perceived stress’). Items that did not satisfy discriminative capacity were rejected. The model fit were acceptable (GFI = 0.98; RSMR = 0.06; AGFI = 0.98; NFI = 0.98; RFI = 0.98). All the factors showed adequate internal consistency as measured by the congeneric model (≥0.91). High and significant associations were observed between perceived stress and burnout, anxiety, depression and resilience. Conclusions The PSQ showed a hierarchical bi-factor structure among Spanish dental students. Using the questionnaire as a uni-dimensional scale may be useful in perceived stress level discrimination, while the sub-factors could help us to refine perceived stress analysis and improve therapeutic processes. PMID:24466330

Complementary exploratory and confirmatory factor analyses of the French WISC-V: Analyses based on the standardization sample.

PubMed

Lecerf, Thierry; Canivez, Gary L

2018-06-01

Interpretation of the French Wechsler Intelligence Scale for Children-Fifth Edition (French WISC-V; Wechsler, 2016a) is based on a 5-factor model including Verbal Comprehension (VC), Visual Spatial (VS), Fluid Reasoning (FR), Working Memory (WM), and Processing Speed (PS). Evidence for the French WISC-V factorial structure was established exclusively through confirmatory factor analyses (CFAs). However, as recommended by Carroll (1995); Reise (2012), and Brown (2015), factorial structure should derive from both exploratory factor analysis (EFA) and CFA. The first goal of this study was to examine the factorial structure of the French WISC-V using EFA. The 15 French WISC-V primary and secondary subtest scaled scores intercorrelation matrix was used and factor extraction criteria suggested from 1 to 4 factors. To disentangle the contribution of first- and second-order factors, the Schmid and Leiman (1957) orthogonalization transformation (SLT) was applied. Overall, no EFA evidence for 5 factors was found. Results indicated that the g factor accounted for about 67% of the common variance and that the contributions of the first-order factors were weak (3.6 to 11.9%). CFA was used to test numerous alternative models. Results indicated that bifactor models produced better fit to these data than higher-order models. Consistent with previous studies, findings suggested dominance of the general intelligence factor and that users should thus emphasize the Full Scale IQ (FSIQ) when interpreting the French WISC-V. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Assessment of seismic design response factors of concrete wall buildings

NASA Astrophysics Data System (ADS)

Mwafy, Aman

2011-03-01

To verify the seismic design response factors of high-rise buildings, five reference structures, varying in height from 20- to 60-stories, were selected and designed according to modern design codes to represent a wide range of concrete wall structures. Verified fiber-based analytical models for inelastic simulation were developed, considering the geometric nonlinearity and material inelasticity of the structural members. The ground motion uncertainty was accounted for by employing 20 earthquake records representing two seismic scenarios, consistent with the latest understanding of the tectonic setting and seismicity of the selected reference region (UAE). A large number of Inelastic Pushover Analyses (IPAs) and Incremental Dynamic Collapse Analyses (IDCAs) were deployed for the reference structures to estimate the seismic design response factors. It is concluded that the factors adopted by the design code are adequately conservative. The results of this systematic assessment of seismic design response factors apply to a wide variety of contemporary concrete wall buildings with various characteristics.

Mechanical behavior and shape optimization of lining structure for subsea tunnel excavated in weathered slot

NASA Astrophysics Data System (ADS)

Li, Peng-fei; Zhou, Xiao-jun

2015-12-01

Subsea tunnel lining structures should be designed to sustain the loads transmitted from surrounding ground and groundwater during excavation. Extremely high pore-water pressure reduces the effective strength of the country rock that surrounds a tunnel, thereby lowering the arching effect and stratum stability of the structure. In this paper, the mechanical behavior and shape optimization of the lining structure for the Xiang'an tunnel excavated in weathered slots are examined. Eight cross sections with different geometric parameters are adopted to study the mechanical behavior and shape optimization of the lining structure. The hyperstatic reaction method is used through finite element analysis software ANSYS. The mechanical behavior of the lining structure is evidently affected by the geometric parameters of crosssectional shape. The minimum safety factor of the lining structure elements is set to be the objective function. The efficient tunnel shape to maximize the minimum safety factor is identified. The minimum safety factor increases significantly after optimization. The optimized cross section significantly improves the mechanical characteristics of the lining structure and effectively reduces its deformation. Force analyses of optimization process and program are conducted parametrically so that the method can be applied to the optimization design of other similar structures. The results obtained from this study enhance our understanding of the mechanical behavior of the lining structure for subsea tunnels. These results are also beneficial to the optimal design of lining structures in general.

Thermal expansion of composites: Methods and results. [large space structures

NASA Technical Reports Server (NTRS)

Bowles, D. E.; Tenney, D. R.

1981-01-01

The factors controlling the dimensional stability of various components of large space structures were investigated. Cyclic, thermal and mechanical loading were identified as the primary controlling factors of the dimensional stability of cables. For organic matrix composites, such as graphite-epoxy, it was found that these factors include moisture desorption in the space environment, thermal expansion as the structure moves from the sunlight to shadow in its orbit, mechanical loading, and microyielding of the material caused by microcracking of the matrix material. The major focus was placed on the thermal expansion of composites and in particular the development and testing of a method for its measurement.

Selective Mutism Questionnaire: measurement structure and validity.

PubMed

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.

Psychometric modeling of abuse and dependence symptoms across six illicit substances indicates novel dimensions of misuse

PubMed Central

Clark, Shaunna L.; Gillespie, Nathan A.; Adkins, Daniel E.; Kendler, Kenneth S.; Neale, Michael C.

2015-01-01

Aims This study explored the factor structure of DSM III-R/IV symptoms for substance abuse and dependence across six illicit substance categories in a population-based sample of males. Method DSM III-R/IV drug abuse and dependence symptoms for cannabis, sedatives, stimulants, cocaine, opioids and hallucinogens from 4179 males born 1940-1970 from the population-based Virginia Adult Twin Study of Psychiatric and Substance Use Disorders were analyzed. Confirmatory factor analyses tested specific hypotheses regarding the latent structure of substance misuse for a comprehensive battery of 13 misuse symptoms measured across six illicit substance categories (78 items). Results Among the models fit, the latent structure of substance misuse was best represented by a combination of substance-specific factors and misuse symptom-specific factors. We found no support for a general liability factor to illicit substance misuse. Conclusions Results indicate that liability to misuse illicit substances is drug class specific, with little evidence for a general liability factor. Additionally, unique dimensions capturing propensity toward specific misuse symptoms (e.g., tolerance, withdrawal) across substances were identified. While this finding requires independent replication, the possibility of symptom-specific misuse factors, present in multiple substances, raises the prospect of genetic, neurobiological and behavioral predispositions toward distinct, narrowly defined features of drug abuse and dependence. PMID:26517709

Cognitive Abilities Explain Wording Effects in the Rosenberg Self-Esteem Scale.

PubMed

Gnambs, Timo; Schroeders, Ulrich

2017-12-01

There is consensus that the 10 items of the Rosenberg Self-Esteem Scale (RSES) reflect wording effects resulting from positively and negatively keyed items. The present study examined the effects of cognitive abilities on the factor structure of the RSES with a novel, nonparametric latent variable technique called local structural equation models. In a nationally representative German large-scale assessment including 12,437 students competing measurement models for the RSES were compared: a bifactor model with a common factor and a specific factor for all negatively worded items had an optimal fit. Local structural equation models showed that the unidimensionality of the scale increased with higher levels of reading competence and reasoning, while the proportion of variance attributed to the negatively keyed items declined. Wording effects on the factor structure of the RSES seem to represent a response style artifact associated with cognitive abilities.

Ion-ion dynamic structure factor of warm dense mixtures

DOE PAGES

Gill, N. M.; Heinonen, R. A.; Starrett, C. E.; ...

2015-06-25

In this study, the ion-ion dynamic structure factor of warm dense matter is determined using the recently developed pseudoatom molecular dynamics method [Starrett et al., Phys. Rev. E 91, 013104 (2015)]. The method uses density functional theory to determine ion-ion pair interaction potentials that have no free parameters. These potentials are used in classical molecular dynamics simulations. This constitutes a computationally efficient and realistic model of dense plasmas. Comparison with recently published simulations of the ion-ion dynamic structure factor and sound speed of warm dense aluminum finds good to reasonable agreement. Using this method, we make predictions of the ion-ionmore » dynamical structure factor and sound speed of a warm dense mixture—equimolar carbon-hydrogen. This material is commonly used as an ablator in inertial confinement fusion capsules, and our results are amenable to direct experimental measurement.« less

Thinking Structurally About Narcissism: An Examination of the Five-Factor Narcissism Inventory and Its Components.

PubMed

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.

The structure of coping among older adults living with HIV/AIDS and depressive symptoms

PubMed Central

Hansen, Nathan B; Harrison, Blair; Fambro, Stacy; Bodnar, Sara; Heckman, Timothy G; Sikkema, Kathleen J

2013-01-01

One-third of adults living with HIV/AIDS are over the age of 50. This study evaluated the structure of coping among 307 older adults living with HIV/AIDS. Participants completed 61 coping items and measures of anxiety, depression, loneliness, and coping self-efficacy. Exploratory factor analyses retained 40 coping items loading on five specific first order factors (Distancing Avoidance, Social Support Seeking, Self-Destructive Avoidance, Spiritual Coping, and Solution-Focused Coping) and two general second order factors (Active and Avoidant Coping). Factors demonstrated good reliability and validity. Results suggest that general coping factors should be considered with specific factors when measuring coping among older adults. PMID:22453164

Parameter Accuracy in Meta-Analyses of Factor Structures

ERIC Educational Resources Information Center

Gnambs, Timo; Staufenbiel, Thomas

2016-01-01

Two new methods for the meta-analysis of factor loadings are introduced and evaluated by Monte Carlo simulations. The direct method pools each factor loading individually, whereas the indirect method synthesizes correlation matrices reproduced from factor loadings. The results of the two simulations demonstrated that the accuracy of…

Factor Analysis of the Autism Spectrum Screening Questionnaire

ERIC Educational Resources Information Center

Posserud, Britt; Lundervold, Astri J.; Steijnen, Maaike C.; Verhoeven, Sophie; Stormark, Kjell Morten; Gillberg, Christopher

2008-01-01

The present study investigated the factor structure of parent and teacher Autism Spectrum Screening Questionnaire (ASSQ) in a population of 7-9 years old children. For validation purposes, factors derived were correlated with results on the Strengths and Difficulties Questionnaire (SDQ). A three-factor solution was identified on both parent and…

A confirmatory factor analytic validation of the Tinnitus Handicap Inventory.

PubMed

Kleinstäuber, Maria; Frank, Ina; Weise, Cornelia

2015-03-01

Because the postulated three-factor structure of the internationally widely used Tinnitus Handicap Inventory (THI) has not been confirmed yet by a confirmatory factor analytic approach this was the central aim of the current study. From a clinical setting, N=373 patients with chronic tinnitus completed the THI and further questionnaires assessing tinnitus-related and psychological variables. In order to analyze the psychometric properties of the THI, confirmatory factor analysis (CFA) and correlational analyses were conducted. CFA provided a statistically significant support for a better fit of the data to the hypothesized three-factor structure (RMSEA=.049, WRMR=1.062, CFI=.965, TLI=.961) than to a general factor model (RMSEA=.062, WRMR=1.258, CFI=.942, TLI=.937). The calculation of Cronbach's alpha as indicator of internal consistency revealed satisfactory values (.80-.91) with the exception of the catastrophic subscale (.65). High positive correlations of the THI and its subscales with other measures of tinnitus distress, anxiety, and depression, high negative correlations with tinnitus acceptance, moderate positive correlations with anxiety sensitivity, sleeping difficulties, tinnitus loudness, and small correlations with the Big Five personality dimensions confirmed construct validity. Results show that the THI is a highly reliable and valid measure of tinnitus-related handicap. In contrast to results of previous exploratory analyses the current findings speak for a three-factor in contrast to a unifactorial structure. Future research is needed to replicate this result in different tinnitus populations. Copyright © 2015 Elsevier Inc. All rights reserved.

Genetic variability and ontogeny predict microbiome structure in a disease-challenged montane amphibian.

PubMed

Griffiths, Sarah M; Harrison, Xavier A; Weldon, Ché; Wood, Michael D; Pretorius, Abigail; Hopkins, Kevin; Fox, Graeme; Preziosi, Richard F; Antwis, Rachael E

2018-06-25

Amphibian populations worldwide are at risk of extinction from infectious diseases, including chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). Amphibian cutaneous microbiomes interact with Bd and can confer protective benefits to the host. The composition of the microbiome itself is influenced by many environment- and host-related factors. However, little is known about the interacting effects of host population structure, genetic variation and developmental stage on microbiome composition and Bd prevalence across multiple sites. Here we explore these questions in Amietia hymenopus, a disease-affected frog in southern Africa. We use microsatellite genotyping and 16S amplicon sequencing to show that the microbiome associated with tadpole mouthparts is structured spatially, and is influenced by host genotype and developmental stage. We observed strong genetic structure in host populations based on rivers and geographic distances, but this did not correspond to spatial patterns in microbiome composition. These results indicate that demographic and host genetic factors affect microbiome composition within sites, but different factors are responsible for host population structure and microbiome structure at the between-site level. Our results help to elucidate complex within- and among- population drivers of microbiome structure in amphibian populations. That there is a genetic basis to microbiome composition in amphibians could help to inform amphibian conservation efforts against infectious diseases.

Internal quantum efficiency enhancement of GaInN/GaN quantum-well structures using Ag nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iida, Daisuke; Department of Photonics Engineering, Technical University of Denmark, 2800 Lyngby; Faculty of Science and Technology, Meijo University, 1-501 Shiogamaguchi Tempaku, 468-8502 Nagoya

2015-09-15

We report internal quantum efficiency enhancement of thin p-GaN green quantum-well structure using self-assembled Ag nanoparticles. Temperature dependent photoluminescence measurements are conducted to determine the internal quantum efficiency. The impact of excitation power density on the enhancement factor is investigated. We obtain an internal quantum efficiency enhancement by a factor of 2.3 at 756 W/cm{sup 2}, and a factor of 8.1 at 1 W/cm{sup 2}. A Purcell enhancement up to a factor of 26 is estimated by fitting the experimental results to a theoretical model for the efficiency enhancement factor.

The Dimensions of Facebook Addiction as Measured by Facebook Addiction Italian Questionnaire and Their Relationships with Individual Differences.

PubMed

Caci, Barbara; Cardaci, Maurizio; Scrima, Fabrizio; Tabacchi, Marco Elio

2017-04-01

The studies reported analyze the factorial structure of Facebook Addiction Italian Questionnaire (FAIQ), a variant of 20-item Young's Internet Addiction Test (IAT). In Study 1, we tested FAIQ psychometric properties using exploratory factor analysis (EFA). In Study 2, we performed a confirmatory factor analysis (CFA) to verify the FAIQ factorial structure identified through EFA. Results from CFA confirm the presence of a four-factor model accounting for 58 percent of total variance, plus a general higher order factor that best fits the data. Further relationships between FAIQ factor scores, personality, and Facebook usage have been explored.

Cross-Validation of the Implementation Leadership Scale (ILS) in Child Welfare Service Organizations.

PubMed

Finn, Natalie K; Torres, Elisa M; Ehrhart, Mark G; Roesch, Scott C; Aarons, Gregory A

2016-08-01

The Implementation Leadership Scale (ILS) is a brief, pragmatic, and efficient measure that can be used for research or organizational development to assess leader behaviors and actions that actively support effective implementation of evidence-based practices (EBPs). The ILS was originally validated with mental health clinicians. This study validates the ILS factor structure with providers in community-based organizations (CBOs) providing child welfare services. Participants were 214 service providers working in 12 CBOs that provide child welfare services. All participants completed the ILS, reporting on their immediate supervisor. Confirmatory factor analyses were conducted to examine the factor structure of the ILS. Internal consistency reliability and measurement invariance were also examined. Confirmatory factor analyses showed acceptable fit to the hypothesized first- and second-order factor structure. Internal consistency reliability was strong and there was partial measurement invariance for the first-order factor structure when comparing child welfare and mental health samples. The results support the use of the ILS to assess leadership for implementation of EBPs in child welfare organizations. © The Author(s) 2016.

Static structure of active Brownian hard disks

NASA Astrophysics Data System (ADS)

de Macedo Biniossek, N.; Löwen, H.; Voigtmann, Th; Smallenburg, F.

2018-02-01

We explore the changes in static structure of a two-dimensional system of active Brownian particles (ABP) with hard-disk interactions, using event-driven Brownian dynamics simulations. In particular, the effect of the self-propulsion velocity and the rotational diffusivity on the orientationally-averaged fluid structure factor is discussed. Typically activity increases structural ordering and generates a structure factor peak at zero wave vector which is a precursor of motility-induced phase separation. Our results provide reference data to test future statistical theories for the fluid structure of active Brownian systems. This manuscript was submitted for the special issue of the Journal of Physics: Condensed Matter associated with the Liquid Matter Conference 2017.

The Structure of Personality Disorders in Individuals with Posttraumatic Stress Disorder

PubMed Central

Wolf, Erika J.; Miller, Mark W.; Brown, Timothy A.

2015-01-01

Research on the structure of personality disorders (PDs) has relied primarily on exploratory analyses to evaluate trait-based models of the factors underlying the covariation of these disorders. This study used confirmatory factor analysis to evaluate whether a model that included both PD traits and a general personality dysfunction factor would account for the comorbidity of the PDs better than a trait-only model. It also examined if the internalizing/externalizing model of psychopathology, developed previously through research on the structure of Axis I disorders, might similarly account for the covariation of the Axis II disorders in a sample of 245 veterans and non-veterans with posttraumatic stress disorder. Results indicated that the best fitting model was a modified bifactor structure composed of nine lower-order common factors. These factors indexed pathology ranging from aggression to dependency, with the correlations among them accounted for by higher-order Internalizing and Externalizing factors. Further, a general factor, reflecting a construct that we termed boundary disturbance, accounted for additional variance and covariance across nearly all the indicators. The Internalizing, Externalizing, and Boundary Disturbance factors evidenced differential associations with trauma-related covariates. These findings suggest continuity in the underlying structure of psychopathology across DSM-IV Axes I & II and provide empirical evidence of a pervasive, core disturbance in the boundary between self and other across the PDs. PMID:22448802

Factor Structure and Longitudinal Measurement Invariance of the Demand Control Support Model: An Evidence from the Swedish Longitudinal Occupational Survey of Health (SLOSH)

PubMed Central

Chungkham, Holendro Singh; Ingre, Michael; Karasek, Robert; Westerlund, Hugo; Theorell, Töres

2013-01-01

Objectives To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). Methods A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. Results Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. Conclusion Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes. PMID:23950957

Brief Report: Repetitive Behaviours in Greek Individuals with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Georgiades, Stelios; Papageorgiou, Vaya; Anagnostou, Evdokia

2010-01-01

The main objective of this study was to examine the factor structure of restricted repetitive behaviours (RRBs) in a sample of 205 Greek individuals with Autism Spectrum Disorder (ASD), using the Repetitive Behavior Scale-Revised (RBS-R). Results show that the structure of RRBs in this Greek sample can be described using a 2-factor solution. The…

Super's Stages and the Four-Factor Structure of the Adult Career Concerns Inventory in an Australian Sample.

ERIC Educational Resources Information Center

Smart, Roslyn M.; Peterson, Candida C.

1994-01-01

Examined four-factor structure of Adult Career Concerns Inventory (ACCI) in sample of 457 employed Australians. Findings support factorial validity of ACCI by showing its congruence with Super et al.'s (1957) hypothesized 4 stages and 12 substages of career development. Results also demonstrated substantial cross-cultural support for ACCI factor…

Path Analysis of the SCL-90-R: Exploring Use in Outpatient Assessment

ERIC Educational Resources Information Center

Grande, Todd L.; Newmeyer, Mark D.; Underwood, Lee A.; Williams, Cyrus R., III

2014-01-01

The Symptom Checklist-90-Revised (SCL-90-R) is a widely used assessment of mental health pathology; however, its factor structure has been called into question by numerous studies. This study assessed a community mental health outpatient sample (N = 336) with the SCL-90-R and analyzed the factor structure. The results indicated that the SCL-90-R…

A Confirmatory Factor Analysis of the Student Evidence-Based Practice Questionnaire (S-EBPQ) in an Australian sample.

PubMed

Beccaria, Lisa; Beccaria, Gavin; McCosker, Catherine

2018-03-01

It is crucial that nursing students develop skills and confidence in using Evidence-Based Practice principles early in their education. This should be assessed with valid tools however, to date, few measures have been developed and applied to the student population. To examine the structural validity of the Student Evidence-Based Practice Questionnaire (S-EBPQ), with an Australian online nursing student cohort. A cross-sectional study for constructing validity. Three hundred and forty-five undergraduate nursing students from an Australian regional university were recruited across two semesters. Confirmatory Factor Analysis was used to examine the structural validity. Confirmatory Factor Analysis was applied which resulted in a good fitting model, based on a revised 20-item tool. The S-EBPQ tool remains a psychometrically robust measure of evidence-based practice use, attitudes, and knowledge and skills and can be applied in an online Australian student context. The findings of this study provided further evidence of the reliability and four factor structure of the S-EBPQ. Opportunities for further refinement of the tool may result in improvements in structural validity. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Construct Validity of Attitudes toward Career Counseling Scale for Korean College Students

ERIC Educational Resources Information Center

Nam, Suk Kyung; In Park, Hyung

2015-01-01

This study aimed to examine the construct validity of the Attitudes Toward Career Counseling Scale (ATCCS) in Korea. In Study 1, confirmatory factor analysis (CFA) was used for testing the factor structure of the scale. The results supported a two-factor (value and stigma) model, which was theoretically driven from the original study. Results of…

Personality structure in the domestic cat (Felis silvestris catus), Scottish wildcat (Felis silvestris grampia), clouded leopard (Neofelis nebulosa), snow leopard (Panthera uncia), and African lion (Panthera leo): a comparative study.

PubMed

Gartner, Marieke Cassia; Powell, David M; Weiss, Alexander

2014-11-01

Although the study of nonhuman personality has increased in the last decade, there are still few studies on felid species, and the majority focus on domestic cats. We assessed the structure of personality and its reliability in five felids-domestic cats, clouded leopards, snow leopards, African lions, and previous data on Scottish wildcats-and compared the results. In addition to the benefits of understanding more about this taxon, comparative studies of personality structure have the potential to provide information on evolutionary relationships among closely related species. Each of the species studied was found to have three factors of personality. Scottish wildcats' factors were labeled Dominance, Agreeableness, and Self Control; domestic cats' factors were Dominance, Impulsiveness, and Neuroticism; clouded leopards' factors were Dominance/Impulsiveness, Agreeableness/Openness, and Neuroticism; snow leopards' factors were Dominance, Impulsiveness/Openness, and Neuroticism; and African lions' factors were Dominance, Impulsiveness, and Neuroticism. The Neuroticism and Impulsiveness factors were similar, as were two of the Dominance factors. A taxon-level personality structure also showed three similar factors. Age and sex effects are also discussed. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Replace-approximation method for ambiguous solutions in factor analysis of ultrasonic hepatic perfusion

NASA Astrophysics Data System (ADS)

Zhang, Ji; Ding, Mingyue; Yuchi, Ming; Hou, Wenguang; Ye, Huashan; Qiu, Wu

2010-03-01

Factor analysis is an efficient technique to the analysis of dynamic structures in medical image sequences and recently has been used in contrast-enhanced ultrasound (CEUS) of hepatic perfusion. Time-intensity curves (TICs) extracted by factor analysis can provide much more diagnostic information for radiologists and improve the diagnostic rate of focal liver lesions (FLLs). However, one of the major drawbacks of factor analysis of dynamic structures (FADS) is nonuniqueness of the result when only the non-negativity criterion is used. In this paper, we propose a new method of replace-approximation based on apex-seeking for ambiguous FADS solutions. Due to a partial overlap of different structures, factor curves are assumed to be approximately replaced by the curves existing in medical image sequences. Therefore, how to find optimal curves is the key point of the technique. No matter how many structures are assumed, our method always starts to seek apexes from one-dimensional space where the original high-dimensional data is mapped. By finding two stable apexes from one dimensional space, the method can ascertain the third one. The process can be continued until all structures are found. This technique were tested on two phantoms of blood perfusion and compared to the two variants of apex-seeking method. The results showed that the technique outperformed two variants in comparison of region of interest measurements from phantom data. It can be applied to the estimation of TICs derived from CEUS images and separation of different physiological regions in hepatic perfusion.

Factor structure and validity of the Depression, Anxiety and Stress Scale-21 in Swedish translation.

PubMed

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.

An Empirical Comparison of Competing Factor Structures for the Repeatable Battery for the Assessment of Neuropsychological Status: A Project FRONTIER Study†

PubMed Central

Torrence, Nicole D.; John, Samantha E.; Gavett, Brandon E.; O'Bryant, Sid E.

2016-01-01

The original factor structure of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has received little empirical support, but at least eight alternative factor structures have been identified in the literature. The current study used confirmatory factor analysis to compare the original RBANS model with eight alternatives, which were adjusted to include a general factor. Participant data were obtained from Project FRONTIER, an epidemiological study of rural health, and comprised 341 adults (229 women, 112 men) with mean age of 61.2 years (SD = 12.1) and mean education of 12.4 years (SD = 3.3). A bifactor version of the model proposed by Duff and colleagues provided the best fit to the data (CFI = 0.98; root-mean-squared error of approximation = 0.07), but required further modification to produce appropriate factor loadings. The results support the inclusion of a general factor and provide partial replication of the Duff and colleagues RBANS model. PMID:26429558

Plate and butt-weld stresses beyond elastic limit, material and structural modeling

NASA Technical Reports Server (NTRS)

Verderaime, V.

1991-01-01

Ultimate safety factors of high performance structures depend on stress behavior beyond the elastic limit, a region not too well understood. An analytical modeling approach was developed to gain fundamental insights into inelastic responses of simple structural elements. Nonlinear material properties were expressed in engineering stresses and strains variables and combined with strength of material stress and strain equations similar to numerical piece-wise linear method. Integrations are continuous which allows for more detailed solutions. Included with interesting results are the classical combined axial tension and bending load model and the strain gauge conversion to stress beyond the elastic limit. Material discontinuity stress factors in butt-welds were derived. This is a working-type document with analytical methods and results applicable to all industries of high reliability structures.

Exploratory and Higher-Order Factor Analyses of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Adolescent Subsample

ERIC Educational Resources Information Center

Canivez, Gary L.; Watkins, Marley W.

2010-01-01

The factor structure of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV; Wechsler, 2008a) with the adolescent participants (ages 16-19 years; N = 400) in the standardization sample was assessed using exploratory factor analysis, multiple factor extraction criteria, and higher-order exploratory factor analyses. Results from…

The School Counseling Program Implementation Survey: Initial Instrument Development and Exploratory Factor Analysis

ERIC Educational Resources Information Center

Clemens, Elysia V.; Carey, John C.; Harrington, Karen M.

2010-01-01

This article details the initial development of the School Counseling Program Implementation Survey and psychometric results including reliability and factor structure. An exploratory factor analysis revealed a three-factor model that accounted for 54% of the variance of the intercorrelation matrix and a two-factor model that accounted for 47% of…

Factors Influencing the Job Satisfaction of Health System Employees in Tabriz, Iran

PubMed Central

Bagheri, Shokoufe; Kousha, Ahmad; Janati, Ali; Asghari-Jafarabadi, Mohammad

2012-01-01

Background: Employees can be counseled on how they feel about their job. If any particular dimension of their job is causing them dissatisfaction, they can be assisted to appropriately change it. In this study, we investigated the factors affecting job satisfaction from the perspective of employees working in the health system and thereby a quantitative measure of job satisfaction. Methods: Using eight focus group discussions (n=70), factors affecting job satisfaction of the employees were discussed. The factors identified from literature review were categorized in four groups: structural and managerial, social, work in it-self, environmental and welfare factors. Results: The findings confirmed the significance of structural and managerial, social, work in it-self, environmental and welfare factors in the level of job satisfaction. In addition, a new factor related to individual characteristics such as employee personal characteristics and development was identified. Conclusion: In order to improve the quality and productivity of work, besides, structural and managerial, social, work in it-self, environmental and welfare factors, policy makers should be taken into account individual characteristics of the employee as a factor affecting job satisfaction. PMID:24688933

Effect of suspension property on granule morphology and compaction behavior

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hae-Weon Lee, Guesup Song, In-Sik Suk

1995-12-31

Granule morphology is an important factor during dry pressing, since it has great influences on die flowability, compaction ratio, and resulting green microstructure. Granule morphology and packing structure of ultrafine Si{sub 3}N{sub 4} particles in the granule were optimized during spray drying by adjusting the suspension structure. The particle packing structure of spray-dried granule was investigated with suspension structure. The effects of granule morphology and its particle packing structure on compaction and resultant sintering behavior were evaluated.

Internal structure of the Community Assessment of Psychic Experiences-Positive (CAPE-P15) scale: Evidence for a general factor.

PubMed

Núñez, D; Arias, V; Vogel, E; Gómez, L

2015-07-01

Psychotic-like experiences (PLEs) are prevalent in the general population and are associated with poor mental health and a higher risk of psychiatric disorders. The Community Assessment of Psychic Experiences-Positive (CAPE-P15) scale is a self-screening questionnaire to address subclinical positive psychotic symptoms (PPEs) in community contexts. Although its psychometric properties seem to be adequate to screen PLEs, further research is needed to evaluate certain validity aspects, particularly its internal structure and its functioning in different populations. To uncover the optimal factor structure of the CAPE-P15 scale in adolescents aged 13 to 18 years using factorial analysis methods suitable to manage categorical variables. A sample of 727 students from six secondary public schools and 245 university students completed the CAPE-P15. The dimensionality of the CAPE-P15 was tested through exploratory structural equation models (ESEMs). Based on the ESEM results, we conducted a confirmatory factor analysis (CFA) to contrast two factorial structures that potentially underlie the symptoms described by the scale: a) three correlated factors and b) a hierarchical model composed of a general PLE factor plus three specific factors (persecutory ideation, bizarre experiences, and perceptual abnormalities). The underlying structure of PLEs assessed by the CAPE-P15 is consistent with both multidimensional and hierarchical solutions. However, the latter show the best fit. Our findings reveal the existence of a strong general factor underlying scale scores. Compared with the specific factors, the general factor explains most of the common variance observed in subjects' responses. The findings suggest that the factor structure of subthreshold psychotic experiences addressed by the CAPE-P15 can be adequately represented by a general factor and three separable specific traits, supporting the hypothesis according to which there might be a common source underlying PLEs. Copyright © 2015 Elsevier B.V. All rights reserved.

Factor structure and construct validity of the Anxiety Sensitivity Index among island Puerto Ricans.

PubMed

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.

Does Sluggish Cognitive Tempo Fit within a Bi-factor Model of Attention-Deficit/Hyperactivity Disorder?

PubMed Central

Garner, Annie A.; Peugh, James; Becker, Stephen P.; Kingery, Kathleen M.; Tamm, Leanne; Vaughn, Aaron J.; Ciesielski, Heather; Simon, John O.; Loren, Richard E. A.; Epstein, Jeffery N.

2014-01-01

Objective Studies demonstrate sluggish cognitive tempo (SCT) symptoms to be distinct from inattentive and hyperactive-impulsive dimensions of Attention-Deficit/Hyperactivity Disorder (ADHD). No study has examined SCT within a bi-factor model of ADHD whereby SCT may form a specific factor distinct from inattention and hyperactivity/impulsivity while still fitting within a general ADHD factor, which was the purpose of the current study. Method 168 children were recruited from an ADHD clinic. Most (92%) met diagnostic criteria for ADHD. Parents and teachers completed measures of ADHD and SCT. Results Although SCT symptoms were strongly associated with inattention they loaded onto a factor independent of ADHD ‘g’. Results were consistent across parent and teacher ratings. Conclusions SCT is structurally distinct from inattention as well as from the general ADHD latent symptom structure. Findings support a growing body of research suggesting SCT to be distinct and separate from ADHD. PMID:25005039

Uncovering the influence of social skills and psychosociological factors on pain sensitivity using structural equation modeling.

PubMed

Tanaka, Yoichi; Nishi, Yuki; Nishi, Yuki; Osumi, Michihiro; Morioka, Shu

2017-01-01

Pain is a subjective emotional experience that is influenced by psychosociological factors such as social skills, which are defined as problem-solving abilities in social interactions. This study aimed to reveal the relationships among pain, social skills, and other psychosociological factors by using structural equation modeling. A total of 101 healthy volunteers (41 men and 60 women; mean age: 36.6±12.7 years) participated in this study. To evoke participants' sense of inner pain, we showed them images of painful scenes on a PC screen and asked them to evaluate the pain intensity by using the visual analog scale (VAS). We examined the correlation between social skills and VAS, constructed a hypothetical model based on results from previous studies and the current correlational analysis results, and verified the model's fit using structural equation modeling. We found significant positive correlations between VAS and total social skills values, as well as between VAS and the "start of relationships" subscales. Structural equation modeling revealed that the values for "start of relationships" had a direct effect on VAS values (path coefficient =0.32, p <0.01). In addition, the "start of relationships" had both a direct and an indirect effect on psychological factors via social support. The results indicated that extroverted people are more sensitive to inner pain and tend to get more social support and maintain a better psychological condition.

A biophysical insight into the formation of aggregates upon trifluoroethanol induced structural and conformational changes in garlic cystatin.

PubMed

Siddiqui, Mohd Faizan; Bano, Bilqees

2018-06-06

Intrinsic and extrinsic factors are responsible for the transition of soluble proteins into aggregated form. Trifluoroethanol is among such potent extrinsic factor which facilitates the formation of aggregated structure. It disrupts the interactive forces and destabilizes the native structure of the protein. The present study investigates the effect of trifluoroethanol (TFE) on garlic cystatin. Garlic cystatin was incubated with increasing concentration of TFE (0-90% v/v) for 4 h. Incubation of GPC with TFE induces structural changes thereby resulting in the formation of aggregates. Inactivation of garlic phytocystatin was confirmed by cysteine proteinase inhibitory activity. Garlic cystatin at 30% TFE exhibits native-like secondary structure and high ANS fluorescence, thus suggesting the presence of molten globule state. Circular dichroism and FTIR confirmed the transition of the native alpha-helical structure of garlic cystatin to the beta-sheet structure at 60% TFE. Furthermore, increased ThT fluorescence and redshift in Congo red absorbance assay confirmed the presence of aggregates. Rayleigh and turbidity assay was also performed to validate the aggregation results. Scanning electron microscopy was followed to analyze the morphological changes which confirm the presence of sheath-like structure at 60% TFE. The study sheds light on the conformational behavior of a plant protein when kept under stress condition induced by an extrinsic factor. Copyright © 2018 Elsevier B.V. All rights reserved.

Form factors of the d*(2380 ) resonance

NASA Astrophysics Data System (ADS)

Dong, Yubing; Shen, Pengnian; Zhang, Zongye

2018-06-01

In order to explore the possible physical quantities for judging different structures of the newly observed resonance d*(2380 ), we study its electromagnetic form factors. In addition to the electric charge monopole C 0 , we calculate its electric quadrupole E 2 , magnetic dipole M 1 , and magnetic octupole M 3 form factors on the base of the realistic coupled Δ Δ +C8C8 channel d* wave function with both the S - and D -partial waves. The results show that the magnetic dipole moment and electric quadrupole deformation of d* are 7.602 and 2.53 ×10-2 fm2 , respectively. The calculated magnetic dipole moment in the naive constituent quark model is also compared with the result of D12π picture. By comparing with partial results where the d* state is considered with a single Δ Δ and with a D12π structures, we find that in addition to the charge distribution of d*, the magnetic dipole moment and magnetic radius can be used to discriminate different structures of d*. Moreover, a quite small electric quadrupole deformation indicates that d* is more inclined to a slightly oblate shape due to our compact hexaquark dominated structure of d*.

Magnetoelectric effect in a sandwich structure of gallium arsenide–nickel–tin–nickel

NASA Astrophysics Data System (ADS)

Galichyan, T. A.; Filippov, D. A.; Tihonov, A. A.; Laletin, V. M.; Firsova, T. O.; Manicheva, I. N.

2018-04-01

The results of investigation of the magnetoelectric effect in a nickel-tin-nickel sandwich structure obtained by galvanic deposition of gallium arsenide on a substrate are presented. The technology of constructing such structures is described and the experimental results of the frequency dependence of the effect are presented. It is shown that the use of tin as an intermediate layer reduces the mechanical stresses resulting from the incommensurability of the phases, which permits obtaining qualitative structures with the nickel thickness of about 70 μm. The resulting structures exhibit good adhesion between the layers and have a high quality factor.

Symptom structure and severity: a comparison of responses to the positive and negative syndrome scale (PANSS) between patients with PTSD or schizophrenia.

PubMed

Stefanovics, Elina A; Krystal, John H; Rosenheck, Robert A

2014-05-01

To describe and compare the structure and relative severity of symptoms in clinical trial patients diagnosed with Post Traumatic Stress Disorder (PTSD) or schizophrenia using the Positive and Negative Syndrome Scale (PANSS), developed originally to evaluate symptoms of schizophrenia. This secondary data analysis used baseline PANSS symptom ratings (n=267) from a six-month multicenter randomized placebo-controlled trial of adjunctive risperidone in patients with chronic military-related PTSD. First, using a split-half design, Exploratory Factor Analysis (EFA) was employed to identify independent factors which were then compared to published factor structures for schizophrenia. Next, Confirmatory Factor Analysis (CFA) was applied to the second half of the sample to compare the results of the EFA and published factor structures. Finally, T-tests were used to compare the severity of factor scores between the PTSD sample and the baseline PANSS ratings from the Clinical Antipsychotic Trial for Intervention Effectiveness (CATIE) schizophrenia sample (n=1460). EFA suggested five factors similar to those identified in a summary of 29 schizophrenia studies by Wallwork (Schizophrenia Research, 137:246-250). CFA showed that the five factor Wallwork model fit the data better than the EFA, although both had relatively high goodness of fit. T-tests showed that the PTSD sample had more severe symptoms on the Depressive factor, and the schizophrenia sample on the Positive, Negative, and Disorganized factors, with no significant difference on the Excited factor. Veterans with PTSD had similar symptom structure to patients with schizophrenia on the PANSS, but were less symptomatic on psychosis-related factors and more symptomatic on depression. Dimensional symptom factors can be virtually the same across diagnoses. Published by Elsevier Inc.

Factor structure of PTSD, and relation with gender in trauma survivors from India

PubMed Central

Charak, Ruby; Armour, Cherie; Elklit, Ask; Angmo, Disket; Elhai, Jon D.; Koot, Hans M.

2014-01-01

Background The factor structure of posttraumatic stress disorder (PTSD) has been extensively studied in Western countries. Some studies have assessed its factor structure in Asia (China, Sri Lanka, and Malaysia), but few have directly assessed the factor structure of PTSD in an Indian adult sample. Furthermore, in a largely patriarchal society in India with strong gender roles, it becomes imperative to assess the association between the factors of PTSD and gender. Objective The purpose of the present study was to assess the factor structure of PTSD in an Indian sample of trauma survivors based on prevailing models of PTSD defined in the DSM-IV-TR (APA, 2000), and to assess the relation between PTSD factors and gender. Method The sample comprised of 313 participants (55.9% female) from Jammu and Kashmir, India, who had experienced a natural disaster (N=200) or displacement due to cross-border firing (N=113). Results Three existing PTSD models—two four-factor models (Emotional Numbing and Dysphoria), and a five-factor model (Dysphoric Arousal)—were tested using Confirmatory Factor Analysis with addition of gender as a covariate. The three competing models had similar fit indices although the Dysphoric Arousal model fit significantly better than Emotional Numbing and Dysphoria models. Gender differences were found across the factors of Re-experiencing and Anxious arousal. Conclusions Findings indicate that the Dysphoric Arousal model of PTSD was the best model; albeit the fit indices of all models were fairly similar. Compared to males, females scored higher on factors of Re-experiencing and Anxious arousal. Gender differences found across two factors of PTSD are discussed in light of the social milieu in India. PMID:25413575

Structural modulation of factor VIIa by full-length tissue factor (TF1-263): implication of novel interactions between EGF2 domain and TF.

PubMed

Prasad, Ramesh; Sen, Prosenjit

2018-02-01

Tissue factor (TF)-mediated factor VII (FVII) activation and a subsequent proteolytic TF-FVIIa binary complex formation is the key step initiating the coagulation cascade, with implications in various homeostatic and pathologic scenarios. TF binding allosterically modifies zymogen-like free FVIIa to its highly catalytically active form. As a result of unresolved crystal structure of the full-length TF 1-263 -FVIIa binary complex and free FVIIa, allosteric alterations in FVIIa following its binding to full-length TF and the consequences of these on function are not entirely clear. The present study aims to map and identify structural alterations in FVIIa and TF resulting from full-length TF binding to FVIIa and the key events responsible for enhanced FVIIa activity in coagulation. We constructed the full-length TF 1-263 -FVIIa membrane bound complex using computational modeling and subjected it to molecular dynamics (MD) simulations. MD simulations showed that TF alters the structure of each domain of FVIIa and these combined alterations contribute to enhanced TF-FVIIa activity. Detailed, domain-wise investigation revealed several new non-covalent interactions between TF and FVIIa that were not found in the truncated soluble TF-FVIIa crystal structure. The structural modulation of each FVIIa domain imparted by TF indicated that both inter and intra-domain communication is crucial for allosteric modulation of FVIIa. Our results suggest that these newly formed interactions can provide additional stability to the protease domain and regulate its activity profile by governing catalytic triad (CT) orientation and localization. The unexplored newly formed interactions between EGF2 and TF provides a possible explanation for TF-induced allosteric activation of FVIIa.

Quasi-Static Probabilistic Structural Analyses Process and Criteria

NASA Technical Reports Server (NTRS)

Goldberg, B.; Verderaime, V.

1999-01-01

Current deterministic structural methods are easily applied to substructures and components, and analysts have built great design insights and confidence in them over the years. However, deterministic methods cannot support systems risk analyses, and it was recently reported that deterministic treatment of statistical data is inconsistent with error propagation laws that can result in unevenly conservative structural predictions. Assuming non-nal distributions and using statistical data formats throughout prevailing stress deterministic processes lead to a safety factor in statistical format, which integrated into the safety index, provides a safety factor and first order reliability relationship. The embedded safety factor in the safety index expression allows a historically based risk to be determined and verified over a variety of quasi-static metallic substructures consistent with the traditional safety factor methods and NASA Std. 5001 criteria.

Personality and the latent structure of PTSD comorbidity

PubMed Central

Miller, Mark W.; Wolf, Erika J.

2012-01-01

This study examined the structure of PTSD comorbidity and its relationship to personality in a sample of 214 veterans using data from diagnostic interviews and the Multidimensional Personality Questionnaire-Brief Form (MPQ-BF; Patrick, Curtin, & Tellegen, 2002). Confirmatory factor analyses supported a three factor model composed of Externalizing, Fear and Distress factors. Analyses that examined the location of borderline personality disorder revealed significant cross-loadings for this disorder on both Externalizing and Distress. Structural equation models showed trait negative emotionality to be significantly related to all three comorbidity factors whereas positive emotionality and constraint evidenced specific associations with Distress and Externalizing, respectively. These results shed new light on the location of borderline personality disorder within the internalizing/externalizing model and clarify the relative influence of broad dimensions of personality on patterns of comorbidity. PMID:22480716

Initial validation of the Spanish childhood trauma questionnaire-short form: factor structure, reliability and association with parenting.

PubMed

Hernandez, Ana; Gallardo-Pujol, David; Pereda, Noemí; Arntz, Arnoud; Bernstein, David P; Gaviria, Ana M; Labad, Antonio; Valero, Joaquín; Gutiérrez-Zotes, Jose Alfonso

2013-05-01

The present study examines the internal consistency and factor structure of the Spanish version of the Childhood Trauma Questionnaire-Short Form (CTQ-SF) and the association between the CTQ-SF subscales and parenting style. Cronbach's α and confirmatory factor analyses (CFA) were performed in a female clinical sample (n = 185). Kendall's ι correlations were calculated between the maltreatment and parenting scales in a subsample of 109 patients. The Spanish CTQ-SF showed adequate psychometric properties and a good fit of the 5-factor structure. The neglect and abuse scales were negatively associated with parental care and positively associated with overprotection scales. The results of this study provide initial support for the reliability and validity of the Spanish CTQ-SF.

Study of atomic structure of liquid Hg-In alloys using ab-initio molecular dynamics

NASA Astrophysics Data System (ADS)

Sharma, Nalini; Thakur, Anil; Ahluwalia, P. K.

2015-05-01

Ab-initio molecular dynamics simulations are performed to study the structural properties of liquid Hg-In alloys. The interatomic interactions are described by ab-initio pseudopotentials given by Troullier and Martins. Five liquid Hg-In mixtures (Hg10In90, Hg30In70, Hg50In50, Hg70In30 and Hg90In10) at 299K are considered. The radial distribution function g(r) and structure factor S(q) of considered alloys are compared with respective experimental results for liquid Hg (l-Hg) and (l-In). The radial distribution function g(r) shows the presence of short range order in the systems considered. Smooth curves of Bhatia-Thornton partial structure factors factor shows the presence of liquid state in the considered alloys.

What hinders healthcare professionals in promoting physical activity towards cancer patients? The influencing role of healthcare professionals' concerns, perceived patient characteristics and perceived structural factors.

PubMed

Haussmann, Alexander; Gabrian, Martina; Ungar, Nadine; Jooß, Stefan; Wiskemann, Joachim; Sieverding, Monika; Steindorf, Karen

2018-05-09

Despite a large body of evidence showing that physical activity (PA) is beneficial to patients with cancer, healthcare professionals (HCPs) are promoting it too scarcely. Factors that hinder HCPs from promoting PA have remained understudied so far. Using a qualitative approach, this study aimed at a comprehensive description of influencing factors for HCPs' PA promotion behaviour and at identifying the reasons and mechanisms behind them. Semi-structured interviews with 30 HCPs were undertaken with a focus on concerns, patient characteristics and structural factors. Answers were analysed using thematic analysis. Results revealed that HCPs had concerns regarding a physical overexertion and psychological stress for patients with cancer. A patient's physical condition and the assumed interest in PA, often derived from former PA, turned out to be the most crucial patient characteristics influencing if PA is addressed. Structural factors relevant for PA promotion pertained to in-house structures, HCPs' workload, timing and coordination, information material for HCPs and patients and availability of exercise programs. In conclusion, this study revealed undetected concerns of HCPs and underlined the relevance of patient characteristics and structural conditions for HCPs' PA promotion towards patients with cancer. A broader perspective is needed to assess these factors in their influence on HCPs' PA promotion. © 2018 John Wiley & Sons Ltd.

Psychometric properties of the Body Checking Questionnaire in college women.

PubMed

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.

A novel method for structure-based prediction of ion channel conductance properties.

PubMed Central

Smart, O S; Breed, J; Smith, G R; Sansom, M S

1997-01-01

A rapid and easy-to-use method of predicting the conductance of an ion channel from its three-dimensional structure is presented. The method combines the pore dimensions of the channel as measured in the HOLE program with an Ohmic model of conductance. An empirically based correction factor is then applied. The method yielded good results for six experimental channel structures (none of which were included in the training set) with predictions accurate to within an average factor of 1.62 to the true values. The predictive r2 was equal to 0.90, which is indicative of a good predictive ability. The procedure is used to validate model structures of alamethicin and phospholamban. Two genuine predictions for the conductance of channels with known structure but without reported conductances are given. A modification of the procedure that calculates the expected results for the effect of the addition of nonelectrolyte polymers on conductance is set out. Results for a cholera toxin B-subunit crystal structure agree well with the measured values. The difficulty in interpreting such studies is discussed, with the conclusion that measurements on channels of known structure are required. Images FIGURE 1 FIGURE 3 FIGURE 4 FIGURE 6 FIGURE 10 PMID:9138559

A Confirmatory Factor Analysis of the Academic Motivation Scale with Black College Students

ERIC Educational Resources Information Center

Cokley, Kevin

2015-01-01

The factor structure of the Academic Motivation Scale (AMS) was examined with a sample of 578 Black college students. A confirmatory factor analysis of the AMS was conducted. Results indicated that the hypothesized seven-factor model did not fit the data. Implications for future research with the AMS are discussed.

Indigenous Chinese Personality Constructs: Is the Five-Factor Model Complete?

ERIC Educational Resources Information Center

Cheung, Fanny M.; Leung, Kwok; Zhang, Jian-Xin; Sun, Hai-Fa; Gan, Yi-Qun; Song, Wei-Zhen; Xie, Dong

2001-01-01

Three studies involving Chinese respondents from China and Hong Kong and diverse respondents from Hawaii compared the Chinese Personality Assessment Inventory factor structure with the Revised NEO Personality Inventory (NEO-PI-R) and NEO-Five Factor Inventory. Results supported the universality of the five-factor model, the validity of NEO-PI-R,…

Structure of rapidity divergences in multi-parton scattering soft factors

NASA Astrophysics Data System (ADS)

Vladimirov, Alexey

2018-04-01

We discuss the structure of rapidity divergences that are presented in the soft factors of transverse momentum dependent (TMD) factorization theorems. To provide the discussion on the most general level we consider soft factors for multi-parton scattering. We show that the rapidity divergences are result of the gluon exchanges with the distant transverse plane, and are structurally equivalent to the ultraviolet divergences. It allows to formulate and to prove the renormalization theorem for rapidity divergences. The proof is made with the help the conformal transformation which maps rapidity divergences to ultraviolet divergences. The theorem is the systematic form of the factorization of rapidity divergences, which is required for the definition of TMD parton distributions. In particular, the definition of multi parton distributions is presented. The equivalence of ultraviolet and rapidity divergences leads to the exact relation between soft and rapidity anomalous dimensions. Using this relation we derive the rapidity anomalous dimension at the three-loop order.

The structure of DSM-IV-TR personality disorder diagnoses in NESARC: a reanalysis.

PubMed

Trull, Timothy J; Vergés, Alvaro; Wood, Phillip K; Sher, Kenneth J

2013-12-01

Cox, Clara, Worobec, and Grant (2012) recently presented results from a series of analyses aimed at identifying the factor structure underlying the DSM-IV-TR (APA, 2000) personality diagnoses assessed in the large NESARC study. Cox et al. (2012) concluded that the best fitting model was one that modeled three lower-order factors (the three clusters of PDs as outlined by DSM-IV-TR), which in turn loaded on a single PD higher-order factor. Our reanalyses of the NESARC Wave 1 and Wave 2 data for personality disorder diagnoses revealed that the best fitting model was that of a general PD factor that spans each of the ten DSM-IV PD diagnoses, and our reanalyses do not support the three-cluster hierarchical structure outlined by Cox et al. (2012) and DSM-IV-TR. Finally, we note the importance of modeling the Wave 2 assessment method factor in analyses of NESARC PD data.

Structure of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Criteria for Obsessive–Compulsive Personality Disorder in Patients With Binge Eating Disorder

PubMed Central

Ansell, Emily B; Pinto, Anthony; Edelen, Maria Orlando; Grilo, Carlos M

2013-01-01

Objective To examine 1-, 2-, and 3-factor model structures through confirmatory analytic procedures for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) obsessive–compulsive personality disorder (OCPD) criteria in patients with binge eating disorder (BED). Method Participants were consecutive outpatients (n = 263) with binge eating disorder and were assessed with semi-structured interviews. The 8 OCPD criteria were submitted to confirmatory factor analyses in Mplus Version 4.2 (Los Angeles, CA) in which previously identified factor models of OCPD were compared for fit, theoretical relevance, and parsimony. Nested models were compared for significant improvements in model fit. Results Evaluation of indices of fit in combination with theoretical considerations suggest a multifactorial model is a significant improvement in fit over the current DSM-IV single-factor model of OCPD. Though the data support both 2- and 3-factor models, the 3-factor model is hindered by an underspecified third factor. Conclusion A multifactorial model of OCPD incorporating the factors perfectionism and rigidity represents the best compromise of fit and theory in modelling the structure of OCPD in patients with BED. A third factor representing miserliness may be relevant in BED populations but needs further development. The perfectionism and rigidity factors may represent distinct intrapersonal and interpersonal attempts at control and may have implications for the assessment of OCPD. PMID:19087485

Iterative model building, structure refinement and density modification with the PHENIX AutoBuild wizard.

PubMed

Terwilliger, Thomas C; Grosse-Kunstleve, Ralf W; Afonine, Pavel V; Moriarty, Nigel W; Zwart, Peter H; Hung, Li Wei; Read, Randy J; Adams, Paul D

2008-01-01

The PHENIX AutoBuild wizard is a highly automated tool for iterative model building, structure refinement and density modification using RESOLVE model building, RESOLVE statistical density modification and phenix.refine structure refinement. Recent advances in the AutoBuild wizard and phenix.refine include automated detection and application of NCS from models as they are built, extensive model-completion algorithms and automated solvent-molecule picking. Model-completion algorithms in the AutoBuild wizard include loop building, crossovers between chains in different models of a structure and side-chain optimization. The AutoBuild wizard has been applied to a set of 48 structures at resolutions ranging from 1.1 to 3.2 A, resulting in a mean R factor of 0.24 and a mean free R factor of 0.29. The R factor of the final model is dependent on the quality of the starting electron density and is relatively independent of resolution.

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.…

Calabi-Yau structures on categories of matrix factorizations

NASA Astrophysics Data System (ADS)

Shklyarov, Dmytro

2017-09-01

Using tools of complex geometry, we construct explicit proper Calabi-Yau structures, that is, non-degenerate cyclic cocycles on differential graded categories of matrix factorizations of regular functions with isolated critical points. The formulas involve the Kapustin-Li trace and its higher corrections. From the physics perspective, our result yields explicit 'off-shell' models for categories of topological D-branes in B-twisted Landau-Ginzburg models.

Factor Structure and Item Level Psychometrics of the Social Problem Solving Inventory Revised-Short Form in Traumatic Brain Injury

PubMed Central

Li, Chih-Ying; Waid-Ebbs, Julia; Velozo, Craig A.; Heaton, Shelley C.

2016-01-01

Primary Objective Social problem solving deficits characterize individuals with traumatic brain injury (TBI). Poor social problem solving interferes with daily functioning and productive lifestyles. Therefore, it is of vital importance to use the appropriate instrument to identify deficits in social problem solving for individuals with TBI. This study investigates factor structure and item-level psychometrics of the Social Problem Solving Inventory-Revised Short Form (SPSI-R:S), for adults with moderate and severe TBI. Research Design Secondary analysis of 90 adults with moderate and severe TBI who completed the SPSI-R:S. Methods and Procedures An exploratory factor analysis (EFA), principal components analysis (PCA) and Rasch analysis examined the factor structure and item-level psychometrics of the SPSI-R:S. Main Outcomes and Results The EFA showed three dominant factors, with positively worded items represented as the most definite factor. The other two factors are negative problem solving orientation and skills; and negative problem solving emotion. Rasch analyses confirmed the three factors are each unidimensional constructs. Conclusions The total score interpretability of the SPSI-R:S may be challenging due to the multidimensional structure of the total measure. Instead, we propose using three separate SPSI-R:S subscores to measure social problem solving for the TBI population. PMID:26052731

Validating the Copenhagen Psychosocial Questionnaire (COPSOQ-II) Using Set-ESEM: Identifying Psychosocial Risk Factors in a Sample of School Principals

PubMed Central

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

Validating the Copenhagen Psychosocial Questionnaire (COPSOQ-II) Using Set-ESEM: Identifying Psychosocial Risk Factors in a Sample of School Principals.

PubMed

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.

Assessing a five factor model of PTSD: is dysphoric arousal a unique PTSD construct showing differential relationships with anxiety and depression?

PubMed

Armour, Cherie; Elhai, Jon D; Richardson, Don; Ractliffe, Kendra; Wang, Li; Elklit, Ask

2012-03-01

Posttraumatic stress disorder's (PTSD) latent structure has been widely debated. To date, two four-factor models (Numbing and Dysphoria) have received the majority of factor analytic support. Recently, Elhai et al. (2011) proposed and supported a revised (five-factor) Dysphoric Arousal model. Data were gathered from two separate samples; War veterans and Primary Care medical patients. The three models were compared and the resultant factors of the Dysphoric Arousal model were validated against external constructs of depression and anxiety. The Dysphoric Arousal model provided significantly better fit than the Numbing and Dysphoria models across both samples. When differentiating between factors, the current results support the idea that Dysphoric Arousal can be differentiated from Anxious Arousal but not from Emotional Numbing when correlated with depression. In conclusion, the Dysphoria model may be a more parsimonious representation of PTSD's latent structure in these trauma populations despite superior fit of the Dysphoric Arousal model. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of Colorado Learning Attitudes about Science Survey

NASA Astrophysics Data System (ADS)

Douglas, K. A.; Yale, M. S.; Bennett, D. E.; Haugan, M. P.; Bryan, L. A.

2014-12-01

The Colorado Learning Attitudes about Science Survey (CLASS) is a widely used instrument designed to measure student attitudes toward physics and learning physics. Previous research revealed a fairly complex factor structure. In this study, exploratory and confirmatory factor analyses were conducted on data from an undergraduate introductory physics course (n =3844 ) to determine whether a more parsimonious factor structure exists. Exploratory factor analysis results indicate that many of the items from the original CLASS have poor psychometric properties and could not be used in a revised factor structure. The cross validation showed acceptable fit statistics for a three factor model found in the exploratory factor analysis. This research suggests that a more optimum measurement of students' attitudes about physics and learning physics is obtained with a 15-item instrument, which describes the factors of personal application, personal effort, and problem solving. The proposed revised version of the CLASS offers researchers the opportunity to test a shortened version of the instrument that may be able to provide information about students' attitudes in the areas of personal application of physics, personal effort in a physics course, and approaches to problem solving.

Posttraumatic stress disorder symptom structure in Chinese adolescents exposed to a deadly earthquake.

PubMed

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.

Factor analysis of regional brain activation in bipolar and healthy individuals reveals a consistent modular structure.

PubMed

Fleck, David E; Welge, Jeffrey A; Eliassen, James C; Adler, Caleb M; DelBello, Melissa P; Strakowski, Stephen M

2018-07-01

The neurophysiological substrates of cognition and emotion, as seen with fMRI, are generally explained using modular structures. The present study was designed to probe the modular structure of cognitive-emotional processing in bipolar and healthy individuals using factor analysis and compare the results with current conceptions of the neurophysiology of bipolar disorder. Exploratory factor analysis was used to assess patterns of covariation among brain regions-of-interest activated during the Continuous Performance Task with Emotional and Neutral Distractors in healthy and bipolar individuals without a priori constraints on the number or composition of latent factors. Results indicated a common cognitive-emotional network consisting of prefrontal, medial temporal, limbic, parietal, anterior cingulate and posterior cingulate modules. However, reduced brain activation to emotional stimuli in the frontal, medial temporal and limbic modules was apparent in the bipolar relative to the healthy group, potentially accounting for emotional dysregulation in bipolar disorder. This study is limited by a relatively small sample size recruited at a single site. The results have yet to be validated on a larger independent sample. Although the modular structure of cognitive-emotional processing is similar in bipolar and healthy individuals, activation in response to emotional/neutral cues varies. These findings are not only consistent with recent conceptions of mood regulation in bipolar disorder, but also suggest that regional activation can be considered within tighter modular structures without compromising data interpretation. This demonstration may serve as a template for data reduction in future region-of-interest analyses to increase statistical power. Copyright © 2018 Elsevier B.V. All rights reserved.

Psychometric properties of the Parenting Stress Index with parents of children with autistic disorder.

PubMed

Dardas, L A; Ahmad, M M

2014-06-01

The purpose of this study was to examine the psychometric properties and the theoretical structure of the Parenting Stress Index-short form (PSI-SF) with Jordanian parents of children with autistic disorder. Using a cross-sectional design for data collection, the convenience sample of the study was composed of 184 Jordanian parents of children with autistic disorder. The factor structure for the PSI-SF was examined using confirmatory and exploratory factor analyses. We found that the modified three-factor model (30 items) fits the data significantly better than the 36-item model. The results showed that the 12 items of the Parental Distress sub-scale support the original scale structure. However, items in the Parent-Child Dysfunctional Interaction and Difficult Child sub-scales did not show stability in their structure. The results in this study showed that the PSI-SF in its 30-item model has endorsed the necessary validity of the scale with parents of children with autistic disorder. The study provides information on the effects of Arab culture on the validity of PSI-SF. It is recommended to use the new factors structure of the PSI-SF with the 30 items in the studies that intend to examine the stress among parents with children with autistic disorder in the Arab world. © 2013 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

Factor structure and gender stability in the multidimensional condom attitudes scale.

PubMed

Starosta, Amy J; Berghoff, Christopher R; Earleywine, Mitch

2015-06-01

Sexually transmitted infections continue to trouble the United States and can be attenuated through increased condom use. Attitudes about condoms are an important multidimensional factor that can affect sexual health choices and have been successfully measured using the Multidimensional Condom Attitudes Scale (MCAS). Such attitudes have the potential to vary between men and women, yet little work has been undertaken to identify if the MCAS accurately captures attitudes without being influenced by underlying gender biases. We examined the factor structure and gender invariance on the MCAS using confirmatory factor analysis and item response theory, within-subscale differential item functioning analyses. More than 770 participants provided data via the Internet. Results of differential item functioning analyses identified three items as differentially functioning between the genders, and removal of these items is recommended. Findings confirmed the previously hypothesized multidimensional nature of condom attitudes and the five-factor structure of the MCAS even after the removal of the three problematic items. In general, comparisons across genders using the MCAS seem reasonable from a methodological standpoint. Results are discussed in terms of improving sexual health research and interventions. © The Author(s) 2014.

Validation of the French Version of the Yale Food Addiction Scale: An Examination of Its Factor Structure, Reliability, and Construct Validity in a Nonclinical Sample

PubMed Central

Brunault, Paul; Ballon, Nicolas; Gaillard, Philippe; Réveillère, Christian; Courtois, Robert

2014-01-01

Objective: The concept of food addiction has recently been proposed by applying the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, criteria for substance dependence to eating behaviour. Food addiction has received increased attention given that it may play a role in binge eating, eating disorders, and the recent increase in obesity prevalence. Currently, there is no psychometrically sound tool for assessing food addiction in French. Our study aimed to test the psychometric properties of a French version of the Yale Food Addiction Scale (YFAS) by establishing its factor structure and construct validity in a nonclinical population. Method: A total of 553 participants were assessed for food addiction (French version of the YFAS) and binge eating behaviour (Bulimic Investigatory Test Edinburgh and Binge Eating Scale). We tested the scale’s factor structure (factor analysis for dichotomous data based on tetrachoric correlation coefficients), internal consistency, and construct validity with measures of binge eating. Results: Our results supported a 1-factor structure, which accounted for 54.1% of the variance. This tool had adequate reliability and high construct validity with measures of binge eating in this population, both in its diagnosis and symptom count version. A 2-factor structure explained an additional 9.1% of the variance, and could differentiate between patients with high, compared with low, levels of insight regarding addiction symptoms. Conclusions: In our study, we validated a psychometrically sound French version of the YFAS, both in its symptom count and diagnostic version. Future studies should validate this tool in clinical samples. PMID:25007281

Relativistic effects on x-ray structure factors

NASA Astrophysics Data System (ADS)

Batke, Kilian; Eickerling, Georg

2016-04-01

Today, combined experimental and theoretical charge density studies based on quantum chemical calculations and x-ray diffraction experiments allow for the investigation of the topology of the electron density at subatomic resolution. When studying compounds containing transition metal elements, relativistic effects need to be adequately taken into account not only in quantum chemical calculations of the total electron density ρ ({r}), but also for the atomic scattering factors employed to extract ρ ({r}) from experimental x-ray diffraction data. In the present study, we investigate the magnitude of relativistic effects on x-ray structure factors and for this purpose {F}({{r}}*) have been calculated for the model systems M(C2H2) (M = Ni, Pd, Pt) from four-component molecular wave functions. Relativistic effects are then discussed by a comparison to structure factors obtained from a non-relativistic reference and different quasi-relativistic approximations. We show, that the overall effects of relativity on the structure factors on average amount to 0.81%, 1.51% and 2.78% for the three model systems under investigation, but that for individual reflections or reflection series the effects can be orders of magnitude larger. Employing the quasi-relativistic Douglas-Kroll-Hess second order or the zeroth order regular approximation Hamiltonian takes these effects into account to a large extend, reducing the differences between the (quasi-)relativistic and the non-relativistic result by one order of magnitude. In order to further determine the experimental significance of the results, the magnitude of the relativistic effects is compared to the changes of the model structure factor data when charge transfer and chemical bonding is taken into account by a multipolar expansion of {F}({{r}}*).

Probabilistic analysis of a materially nonlinear structure

NASA Technical Reports Server (NTRS)

Millwater, H. R.; Wu, Y.-T.; Fossum, A. F.

1990-01-01

A probabilistic finite element program is used to perform probabilistic analysis of a materially nonlinear structure. The program used in this study is NESSUS (Numerical Evaluation of Stochastic Structure Under Stress), under development at Southwest Research Institute. The cumulative distribution function (CDF) of the radial stress of a thick-walled cylinder under internal pressure is computed and compared with the analytical solution. In addition, sensitivity factors showing the relative importance of the input random variables are calculated. Significant plasticity is present in this problem and has a pronounced effect on the probabilistic results. The random input variables are the material yield stress and internal pressure with Weibull and normal distributions, respectively. The results verify the ability of NESSUS to compute the CDF and sensitivity factors of a materially nonlinear structure. In addition, the ability of the Advanced Mean Value (AMV) procedure to assess the probabilistic behavior of structures which exhibit a highly nonlinear response is shown. Thus, the AMV procedure can be applied with confidence to other structures which exhibit nonlinear behavior.

Homework Distraction Scale: Confirming the Factor Structure With Middle School Students

ERIC Educational Resources Information Center

Xu, Jianzhong; Fan, Xitao; Du, Jianxia

2016-01-01

The goal of the current investigation was to evaluate psychometric properties of the Homework Distraction Scale (HDS) using 796 middle school students. Results from confirmatory factor analyses (CFAs) supported the presence of two distinct yet related subscales for the HDS: Conventional Distraction and Tech-Related Distraction. Results of…

Evaluating the personality structure of semi-captive Asian elephants living in their natural habitat

PubMed Central

Adams, Mark J.; Mar, Khyne U; Lahdenperä, Mirkka

2018-01-01

Data on personality for long-lived, highly social wild mammals with high cognitive abilities are rare. We investigated the personality structure of Asian elephants (Elephas maximus) by using a large sample of semi-captive timber elephants in Myanmar. Data were collected during 2014–2017 using questionnaires, for which elephant riders (mahouts) rated 28 behavioural adjectives of elephants. Repeated questionnaires were obtained for each elephant from several raters whenever possible, resulting in 690 ratings of 150 female and 107 male elephants. We started by performing a confirmatory factor analysis to compare the fit of our data to a previously published captive elephant personality structure. Owing to a poor fit of this model to our data, we proceeded by performing explanatory factor analysis to determine the personality structure in our study population. This model suggested that personality in these elephants was manifested as three factors that we labelled as Attentiveness, Sociability and Aggressiveness. This structure did not differ between the sexes. These results provide the basis for future research on the link between personality and reproductive success in this endangered species and more generally, help to resolve the selective pressures on personalities in long-lived, highly social species. PMID:29515900

Examining the Factor Structure of the Positive and Negative Affect Schedule (PANAS) in a Multiethnic Sample of Adolescents

ERIC Educational Resources Information Center

Villodas, Feion; Villodas, Miguel T.; Roesch, Scott

2011-01-01

The psychometric properties of the Positive and Negative Affect Schedule were examined in a multiethnic sample of adolescents. Results from confirmatory factor analyses indicated that the original two-factor model did not adequately fit the data. Exploratory factor analyses revealed that four items were not pure markers of the factors. (Contains 1…

Recent advances in computational structural reliability analysis methods

NASA Astrophysics Data System (ADS)

Thacker, Ben H.; Wu, Y.-T.; Millwater, Harry R.; Torng, Tony Y.; Riha, David S.

1993-10-01

The goal of structural reliability analysis is to determine the probability that the structure will adequately perform its intended function when operating under the given environmental conditions. Thus, the notion of reliability admits the possibility of failure. Given the fact that many different modes of failure are usually possible, achievement of this goal is a formidable task, especially for large, complex structural systems. The traditional (deterministic) design methodology attempts to assure reliability by the application of safety factors and conservative assumptions. However, the safety factor approach lacks a quantitative basis in that the level of reliability is never known and usually results in overly conservative designs because of compounding conservatisms. Furthermore, problem parameters that control the reliability are not identified, nor their importance evaluated. A summary of recent advances in computational structural reliability assessment is presented. A significant level of activity in the research and development community was seen recently, much of which was directed towards the prediction of failure probabilities for single mode failures. The focus is to present some early results and demonstrations of advanced reliability methods applied to structural system problems. This includes structures that can fail as a result of multiple component failures (e.g., a redundant truss), or structural components that may fail due to multiple interacting failure modes (e.g., excessive deflection, resonate vibration, or creep rupture). From these results, some observations and recommendations are made with regard to future research needs.

Recent advances in computational structural reliability analysis methods

NASA Technical Reports Server (NTRS)

Thacker, Ben H.; Wu, Y.-T.; Millwater, Harry R.; Torng, Tony Y.; Riha, David S.

1993-01-01

The goal of structural reliability analysis is to determine the probability that the structure will adequately perform its intended function when operating under the given environmental conditions. Thus, the notion of reliability admits the possibility of failure. Given the fact that many different modes of failure are usually possible, achievement of this goal is a formidable task, especially for large, complex structural systems. The traditional (deterministic) design methodology attempts to assure reliability by the application of safety factors and conservative assumptions. However, the safety factor approach lacks a quantitative basis in that the level of reliability is never known and usually results in overly conservative designs because of compounding conservatisms. Furthermore, problem parameters that control the reliability are not identified, nor their importance evaluated. A summary of recent advances in computational structural reliability assessment is presented. A significant level of activity in the research and development community was seen recently, much of which was directed towards the prediction of failure probabilities for single mode failures. The focus is to present some early results and demonstrations of advanced reliability methods applied to structural system problems. This includes structures that can fail as a result of multiple component failures (e.g., a redundant truss), or structural components that may fail due to multiple interacting failure modes (e.g., excessive deflection, resonate vibration, or creep rupture). From these results, some observations and recommendations are made with regard to future research needs.

Probabilistic simulation of the human factor in structural reliability

NASA Technical Reports Server (NTRS)

Chamis, C. C.

1993-01-01

A formal approach is described in an attempt to computationally simulate the probable ranges of uncertainties of the human factor in structural probabilistic assessments. A multi-factor interaction equation (MFIE) model has been adopted for this purpose. Human factors such as marital status, professional status, home life, job satisfaction, work load and health, are considered to demonstrate the concept. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Suitability of the MFIE in the subsequently probabilistic sensitivity studies are performed to assess the validity of the whole approach. Results obtained show that the uncertainties for no error range from five to thirty percent for the most optimistic case.

Construct Validity of the Chinese Version of the Activities of Daily Living Rating Scale III in Patients with Schizophrenia

PubMed Central

Chiu, En-Chi; Lee, Yen; Lai, Kuan-Yu; Kuo, Chian-Jue; Lee, Shu-Chun; Hsieh, Ching-Lin

2015-01-01

Background The Chinese version of the Activities of Daily Living Rating Scale III (ADLRS-III), which has 10 domains, is commonly used for assessing activities of daily living (ADL) in patients with schizophrenia. However, construct validity (i.e., unidimensionality) for each domain of the ADLRS-III is unknown, limiting the explanations of the test results. Purpose This main purpose of this study was to examine unidimensionality of each domain in the ADLRS-III. We also examined internal consistency and ceiling/floor effects in patients with schizophrenia. Methods From occupational therapy records, we obtained 304 self-report data of the ADLRS-III. Confirmatory factor analysis (CFA) was conducted to examine the 10 one-factor structures. If a domain showed an insufficient model fit, exploratory factor analysis (EFA) was performed to investigate the factor structure and choose one factor representing the original construct. Internal consistency was examined using Cronbach’s alpha (α). Ceiling and floor effects were determined by the percentage of patients with the maximum and minimum scores in each domain, respectively. Results CFA analyses showed that 4 domains (i.e., leisure, picture recognition, literacy ability, communication tools use) had sufficient model fits. These 4 domains had acceptable internal consistency (α = 0.79-0.87) and no ceiling/floor effects, except the leisure domain which had a ceiling effect. The other 6 domains showed insufficient model fits. The EFA results showed that these 6 domains were two-factor structures. Conclusion The results supported unidimensional constructs of the leisure, picture recognition, literacy ability, and communication tool uses domains. The sum scores of these 4 domains can be used to represent their respective domain-specific functions. Regarding the 6 domains with insufficient model fits, we have explained the two factors of each domain and chosen one factor to represent its original construct. Future users may use the items from the chosen factors to assess domain-specific functions in patients with schizophrenia. PMID:26121246

[Inter-rater reliability and construct validity of the OPD-CA axis structure: first study results regarding the integration of OPD-CA into clinical practice].

PubMed

Cropp, Carola; Salzer, Simone; Häusser, Leonard F; Streeck-Fischer, Annette

2013-01-01

The axis structure of the Operationalized Psychodynamic Diagnostics in childhood and adolescence (OPD-CA) has proven to be a reliable and valid diagnostic tool under research conditions. However, corresponding data regarding the integration of OPD-CA axis structure into clinical practice is still lacking. Hence, this aspect was examined as part of a randomized controlled clinical trial realized at Asklepios Fachklinikum Tiefenbrunn. Here, the OPD-CA axis structure has been applied to assess the structural level of 42 adolescent patients (15-19 years). In contrast to previous studies, the assessment was not carried out by independent raters using a videotaped OPD-CA interview, but the rating was part of clinical routine procedures. Also under these conditions, inter-rater reliability was high, in particular regarding the four subscales of the OPD-CA axis structure. With respect to construct validity, the results of our study supported a two-factor solution, which is in accordance with the findings of two previous works. One factor corresponded to the dimension "self-regulation" while the other factor included both the dimension "self-perception and object perception" as well as the dimension "communication skills". Implications of the findings for research and practice are discussed.

Improving the Factor Structure of Psychological Scales

PubMed Central

Zhang, Xijuan; Savalei, Victoria

2015-01-01

Many psychological scales written in the Likert format include reverse worded (RW) items in order to control acquiescence bias. However, studies have shown that RW items often contaminate the factor structure of the scale by creating one or more method factors. The present study examines an alternative scale format, called the Expanded format, which replaces each response option in the Likert scale with a full sentence. We hypothesized that this format would result in a cleaner factor structure as compared with the Likert format. We tested this hypothesis on three popular psychological scales: the Rosenberg Self-Esteem scale, the Conscientiousness subscale of the Big Five Inventory, and the Beck Depression Inventory II. Scales in both formats showed comparable reliabilities. However, scales in the Expanded format had better (i.e., lower and more theoretically defensible) dimensionalities than scales in the Likert format, as assessed by both exploratory factor analyses and confirmatory factor analyses. We encourage further study and wider use of the Expanded format, particularly when a scale’s dimensionality is of theoretical interest. PMID:27182074

INFERRING THE CORONAL DENSITY IRREGULARITY FROM EUV SPECTRA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hahn, M.; Savin, D. W., E-mail: mhahn@astro.columbia.edu

2016-09-20

Understanding the density structure of the solar corona is important for modeling both coronal heating and the solar wind. Direct measurements are difficult because of line-of-sight integration and possible unresolved structures. We present a new method for quantifying such structures using density-sensitive extreme ultraviolet line intensities to derive a density irregularity parameter, a relative measure of the amount of structure along the line of sight. We also present a simple model to relate the inferred irregularities to physical quantities, such as the filling factor and density contrast. For quiet-Sun regions and interplume regions of coronal holes, we find a densitymore » contrast of at least a factor of 3–10 and corresponding filling factors of about 10%–20%. Our results are in rough agreement with other estimates of the density structures in these regions. The irregularity diagnostic provides a useful relative measure of unresolved structure in various regions of the corona.« less

The Latent Structure and Test-Retest Stability of Connected Language Measures in the Wisconsin Registry for Alzheimer's Prevention (WRAP).

PubMed

Mueller, Kimberly D; Koscik, Rebecca L; Clark, Lindsay R; Hermann, Bruce P; Johnson, Sterling C; Turkstra, Lyn S

2017-11-24

While it is well known that discourse-related language functions are impaired in the dementia phase of Alzheimer's Disease (AD), the presymptomatic temporal course of discourse dysfunction are not known earlier in the course of AD. To conduct discourse-related studies in this phase of AD, validated psychometric instruments are needed. This study investigates the latent structure, validity, and test-retest stability of discourse measures in a late-middle-aged normative group who are relatively free from sporadic AD risk factors. Using a normative sample of 399 participants (mean age = 61), exploratory factor analyses (EFA) and confirmatory factor analyses (CFA) were conducted on 18 measures of connected language derived from picture descriptions. Factor invariance across sex and family history and longitudinal test-retest stability measures were calculated. The EFA revealed a four-factor solution, consisting of semantic, syntax, fluency, and lexical constructs. The CFA model substantiated the structure, and factors were invariant across sex and parental history of AD status. Test-retest stability measures were within acceptable ranges. Results confirm a factor structure that is invariant across sex and parental AD history. The factor structure could be useful in similar cohorts designed to detect early language decline in investigations of preclinical or clinical AD or as outcome measures in clinical prevention trials. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Factor structure and construct validity of the Generalized Anxiety Disorder 7-item (GAD-7) among Portuguese college students.

PubMed

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.

The factor structure of the Hospital Anxiety and Depression Scale in individuals with traumatic brain injury.

PubMed

Schönberger, Michael; Ponsford, Jennie

2010-10-30

There is a lack of validated scales for screening for anxiety and depression in individuals with traumatic brain injury (TBI). The purpose of this study was to examine the factor structure of the Hospital Anxiety and Depression Scale (HADS) in individuals with TBI. A total of 294 individuals with TBI (72.1% male; mean age 37.1 years, S.D. 17.5, median post-traumatic amnesia (PTA) duration 17 days) completed the HADS 1 year post-injury. A series of confirmatory factor analyses was conducted to examine the fit of a one-, two- and three-factor solution, with and without controlling for item wording effects (Multi-Trait Multi-Method approach). The one-, two- or three-factor model fit the data only when controlling for negative item wording. The results are in support of the validity of the original anxiety and depression subscales of the HADS and demonstrate the importance of evaluating item wording effects when examining the factor structure of a questionnaire. The results would also justify the use of the HADS as a single scale of emotional distress. However, even though the three-factor solution fit the data, alternative scales should be used if the purpose of the assessment is to measure stress symptoms separately from anxiety and depression. Copyright © 2009 Elsevier Ltd. All rights reserved.

The Selective Mutism Questionnaire: Measurement Structure and Validity

PubMed Central

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

Factor Structure and Measurement Invariance of the Need-Supportive Teaching Style Scale for Physical Education.

PubMed

Liu, Jing-Dong; Chung, Pak-Kwong

2017-08-01

The purpose of the current study was to examine the factor structure and measurement invariance of a scale measuring students' perceptions of need-supportive teaching (Need-Supportive Teaching Style Scale in Physical Education; NSTSSPE). We sampled 615 secondary school students in Hong Kong, 200 of whom also completed a follow-up assessment two months later. Factor structure of the scale was examined through exploratory structural equation modeling (ESEM). Further, nomological validity of the NSTSSPE was evaluated by examining the relationships between need-supportive teaching style and student satisfaction of psychological needs. Finally, four measurement models-configural, metric invariance, scalar invariance, and item uniqueness invariance-were assessed using multiple group ESEM to test the measurement invariance of the scale across gender, grade, and time. ESEM results suggested a three-factor structure of the NSTSSPE. Nomological validity was supported, and weak, strong, and strict measurement invariance of the NSTSSPE was evidenced across gender, grade, and time. The current study provides initial psychometric support for the NSTSSPE to assess student perceptions of teachers' need-supportive teaching style in physical education classes.

The Psychometric Properties of the French Version of the Personality Inventory for DSM-5

PubMed Central

Roskam, Isabelle; Galdiolo, Sarah; Hansenne, Michel; Massoudi, Koorosh; Rossier, Jérôme; Gicquel, Ludovic; Rolland, Jean-Pierre

2015-01-01

In the context of the publication of DSM-5, the Personality Inventory for DSM-5 (PID-5) has been proposed as a new dimensional assessment tool for personality disorders. This instrument includes a pool of 220 items organized around 25 facets included in a five-factor second-order domain structure. The examination of the replicability of the trait structure across methods and populations is of primary importance. In view of this need, the main objective of the current study was to validate the French version of the PID-5 among French-speaking adults from a European community sample (N=2,532). In particular, the assumption of unidimensionality of the 25 facet and the five domain scales was tested, as well as the extent to which the five-factor structure of the PID-5 and the DSM-5 personality trait hierarchical structure are replicated in the current sample. The results support the assumption of unidimensionality of both the facets and the domains. Exploratory factor and hierarchical analyses replicated the five-factor structure as initially proposed in the PID-5. PMID:26193699

The Psychometric Properties of the French Version of the Personality Inventory for DSM-5.

PubMed

Roskam, Isabelle; Galdiolo, Sarah; Hansenne, Michel; Massoudi, Koorosh; Rossier, Jérôme; Gicquel, Ludovic; Rolland, Jean-Pierre

2015-01-01

In the context of the publication of DSM-5, the Personality Inventory for DSM-5 (PID-5) has been proposed as a new dimensional assessment tool for personality disorders. This instrument includes a pool of 220 items organized around 25 facets included in a five-factor second-order domain structure. The examination of the replicability of the trait structure across methods and populations is of primary importance. In view of this need, the main objective of the current study was to validate the French version of the PID-5 among French-speaking adults from a European community sample (N=2,532). In particular, the assumption of unidimensionality of the 25 facet and the five domain scales was tested, as well as the extent to which the five-factor structure of the PID-5 and the DSM-5 personality trait hierarchical structure are replicated in the current sample. The results support the assumption of unidimensionality of both the facets and the domains. Exploratory factor and hierarchical analyses replicated the five-factor structure as initially proposed in the PID-5.

Degradation Factor Approach for Impacted Composite Structural Assessment: MSFC Center Director's Discretionary Fund Final Report, Project No. 96-17

NASA Technical Reports Server (NTRS)

Ortega, R.; Price, J. M.; Fox, D.

2000-01-01

This technical memorandum documents the results of the research to develop a concept for assessing the structural integrity of impacted composite structures using the strength degradation factor in conjunction with available finite element tools. For this purpose, a literature search was conducted, a plan for conducting impact testing on two laminates was developed, and a finite element model of the impact process was created. Specimens for the impact testing were fabricated to support the impact testing plan.

Identification of the underlying factor structure of the Derriford Appearance Scale 24

PubMed Central

Lawson, Victoria; White, Paul

2015-01-01

Background. The Derriford Appearance Scale24 (DAS24) is a widely used measure of distress and dysfunction in relation to self-consciousness of appearance. It has been used in clinical and research settings, and translated into numerous European and Asian languages. Hitherto, no study has conducted an analysis to determine the underlying factor structure of the scale. Methods. A large (n = 1,265) sample of community and hospital patients with a visible difference were recruited face to face or by post, and completed the DAS24. Results. A two factor solution was generated. An evaluation of the congruence of the factor solutions on each of the the hospital and the community samples using Tucker’s Coefficient of Congruence (rc = .979) and confirmatory factor analysis, which demonstrated a consistent factor structure. A main factor, general self consciousness (GSC), was represented by 18 items. Six items comprised a second factor, sexual and body self-consciousness (SBSC). The SBSC scale demonstrated greater sensitivity and specificity in identifying distress for sexually significant areas of the body. Discussion. The factor structure of the DAS24 facilitates a more nuanced interpretation of scores using this scale. Two conceptually and statistically coherent sub-scales were identified. The SBSC sub-scale offers a means of identifying distress and dysfunction around sexually significant areas of the body not previously possible with this scale. PMID:26157633

Identification of the underlying factor structure of the Derriford Appearance Scale 24.

PubMed

Moss, Timothy P; Lawson, Victoria; White, Paul

2015-01-01

Background. The Derriford Appearance Scale24 (DAS24) is a widely used measure of distress and dysfunction in relation to self-consciousness of appearance. It has been used in clinical and research settings, and translated into numerous European and Asian languages. Hitherto, no study has conducted an analysis to determine the underlying factor structure of the scale. Methods. A large (n = 1,265) sample of community and hospital patients with a visible difference were recruited face to face or by post, and completed the DAS24. Results. A two factor solution was generated. An evaluation of the congruence of the factor solutions on each of the the hospital and the community samples using Tucker's Coefficient of Congruence (rc = .979) and confirmatory factor analysis, which demonstrated a consistent factor structure. A main factor, general self consciousness (GSC), was represented by 18 items. Six items comprised a second factor, sexual and body self-consciousness (SBSC). The SBSC scale demonstrated greater sensitivity and specificity in identifying distress for sexually significant areas of the body. Discussion. The factor structure of the DAS24 facilitates a more nuanced interpretation of scores using this scale. Two conceptually and statistically coherent sub-scales were identified. The SBSC sub-scale offers a means of identifying distress and dysfunction around sexually significant areas of the body not previously possible with this scale.

Evaluating the Spatio-Temporal Factors that Structure Network Parameters of Plant-Herbivore Interactions

PubMed Central

López-Carretero, Antonio; Díaz-Castelazo, Cecilia; Boege, Karina; Rico-Gray, Víctor

2014-01-01

Despite the dynamic nature of ecological interactions, most studies on species networks offer static representations of their structure, constraining our understanding of the ecological mechanisms involved in their spatio-temporal stability. This is the first study to evaluate plant-herbivore interaction networks on a small spatio-temporal scale. Specifically, we simultaneously assessed the effect of host plant availability, habitat complexity and seasonality on the structure of plant-herbivore networks in a coastal tropical ecosystem. Our results revealed that changes in the host plant community resulting from seasonality and habitat structure are reflected not only in the herbivore community, but also in the emergent properties (network parameters) of the plant-herbivore interaction network such as connectance, selectiveness and modularity. Habitat conditions and periods that are most stressful favored the presence of less selective and susceptible herbivore species, resulting in increased connectance within networks. In contrast, the high degree of selectivennes (i.e. interaction specialization) and modularity of the networks under less stressful conditions was promoted by the diversification in resource use by herbivores. By analyzing networks at a small spatio-temporal scale we identified the ecological factors structuring this network such as habitat complexity and seasonality. Our research offers new evidence on the role of abiotic and biotic factors in the variation of the properties of species interaction networks. PMID:25340790

Identification of eight novel coagulation factor XIII subunit A mutations: implied consequences for structure and function

PubMed Central

Ivaskevicius, Vytautas; Biswas, Arijit; Bevans, Carville; Schroeder, Verena; Kohler, Hans Peter; Rott, Hannelore; Halimeh, Susan; Petrides, Petro E.; Lenk, Harald; Krause, Manuele; Miterski, Bruno; Harbrecht, Ursula; Oldenburg, Johannes

2010-01-01

Background Severe hereditary coagulation factor XIII deficiency is a rare homozygous bleeding disorder affecting one person in every two million individuals. In contrast, heterozygous factor XIII deficiency is more common, but usually not associated with severe hemorrhage such as intracranial bleeding or hemarthrosis. In most cases, the disease is caused by F13A gene mutations. Causative mutations associated with the F13B gene are rarer. Design and Methods We analyzed ten index patients and three relatives for factor XIII activity using a photometric assay and sequenced their F13A and F13B genes. Additionally, structural analysis of the wild-type protein structure from a previously reported X-ray crystallographic model identified potential structural and functional effects of the missense mutations. Results All individuals except one were heterozygous for factor XIIIA mutations (average factor XIII activity 51%), while the remaining homozygous individual was found to have severe factor XIII deficiency (<5% of normal factor XIII activity). Eight of the 12 heterozygous patients exhibited a bleeding tendency upon provocation. Conclusions The identified missense (Pro289Arg, Arg611His, Asp668Gly) and nonsense (Gly390X, Trp664X) mutations are causative for factor XIII deficiency. A Gly592Ser variant identified in three unrelated index patients, as well as in 200 healthy controls (minor allele frequency 0.005), and two further Tyr167Cys and Arg540Gln variants, represent possible candidates for rare F13A gene polymorphisms since they apparently do not have a significant influence on the structure of the factor XIIIA protein. Future in vitro expression studies of the factor XIII mutations are required to confirm their pathological mechanisms. PMID:20179087

Multidimensional Structure of the Hypomanic Personality Scale

ERIC Educational Resources Information Center

Schalet, Benjamin D.; Durbin, C. Emily; Revelle, William

2011-01-01

The structure of the Hypomanic Personality Scale was explored in a sample of young adults (N = 884); resulting structures were validated on subsamples with measures of personality traits, internalizing symptoms, and externalizing behaviors. Hierarchical cluster analysis and estimates of general factor saturation suggested the presence of a weak…

Internal Structure and Clinical Utility of the Anxiety Control Questionnaire-Revised (ACQ-R) Spanish Version.

PubMed

Osma, Jorge; Barrada, Juan Ramón; García-Palacios, Azucena; Navarro-Haro, María; Aguilar, Alejandra

2016-10-03

Perceived control has shown predictive value for anxiety severity symptoms as well as cognitive-behavior therapy outcomes. The most commonly used measure of perceived control is the Anxiety Control Questionnaire (ACQ), and more recently the ACQ Revised (ACQ-R). However, both questionnaires have shown structural inconsistencies among several studies. Also, although the ACQ and ACQ-R seem to be multidimensional instruments, a single total score have been commonly used. This study examined the internal structure of the ACQ-R Spanish version using exploratory factor and exploratory bi-factor analysis in a sample of 382 college students and 52 people diagnosed of panic disorder (with or without agoraphobia). Also, in this study we assessed the preliminary diagnostic value of the ACQ-R scores. The results indicated that the ACQ-R Spanish version structure consisted of two factors: one related with perceived control of internal emotional reactions (Emotion Control) and another related with perceived control of external events (Threat and Stress Control). Both specific factors can be adequately summarized by a general factor (General Anxiety Perception of Control; CFI = .973, TLI = .954, RMSEA = .039; p = .002), which accounted for 70% of the common explained variance. The correlations between the ACQ-R scores and with variables like anxiety (r = -.66) or anxiety sensitivity (r = -.50) presented the expected pattern of results. Either the two dimensions structure or the total score have proved to be a good tool to distinguish between participants with panic disorder and non-clinical samples (area under the curve = 0.79).

Using Structured Additive Regression Models to Estimate Risk Factors of Malaria: Analysis of 2010 Malawi Malaria Indicator Survey Data

PubMed Central

Chirombo, James; Lowe, Rachel; Kazembe, Lawrence

2014-01-01

Background After years of implementing Roll Back Malaria (RBM) interventions, the changing landscape of malaria in terms of risk factors and spatial pattern has not been fully investigated. This paper uses the 2010 malaria indicator survey data to investigate if known malaria risk factors remain relevant after many years of interventions. Methods We adopted a structured additive logistic regression model that allowed for spatial correlation, to more realistically estimate malaria risk factors. Our model included child and household level covariates, as well as climatic and environmental factors. Continuous variables were modelled by assuming second order random walk priors, while spatial correlation was specified as a Markov random field prior, with fixed effects assigned diffuse priors. Inference was fully Bayesian resulting in an under five malaria risk map for Malawi. Results Malaria risk increased with increasing age of the child. With respect to socio-economic factors, the greater the household wealth, the lower the malaria prevalence. A general decline in malaria risk was observed as altitude increased. Minimum temperatures and average total rainfall in the three months preceding the survey did not show a strong association with disease risk. Conclusions The structured additive regression model offered a flexible extension to standard regression models by enabling simultaneous modelling of possible nonlinear effects of continuous covariates, spatial correlation and heterogeneity, while estimating usual fixed effects of categorical and continuous observed variables. Our results confirmed that malaria epidemiology is a complex interaction of biotic and abiotic factors, both at the individual, household and community level and that risk factors are still relevant many years after extensive implementation of RBM activities. PMID:24991915

Development of a New Multidimensional Individual and Interpersonal Resilience Measure for Older Adults

PubMed Central

Martin, A’verria Sirkin; Distelberg, Brian; Palmer, Barton W.; Jeste, Dilip V.

2015-01-01

Objectives Develop an empirically grounded measure that can be used to assess family and individual resilience in a population of older adults (aged 50-99). Methods Cross-sectional, self-report data from 1,006 older adults were analyzed in two steps. The total sample was split into two sub-samples and the first step identified the underlying latent structure through principal component Exploratory Factor Analysis (EFA). The second step utilized the second half of the sample to validate the derived latent structure through Confirmatory Factor Analysis (CFA). Results EFA produced an eight-factor structure that appeared clinically relevant for measuring the multidimensional nature of resilience. Factors included self-efficacy, access to social support network, optimism, perceived economic and social resources, spirituality and religiosity, relational accord, emotional expression and communication, and emotional regulation. CFA confirmed the eight-factor structure previously achieved with covariance between each of the factors. Based on these analyses we developed the Multidimensional Individual and Interpersonal Resilience Measure (MIIRM), a broad assessment of resilience for older adults. Conclusion This study highlights the multidimensional nature of resilience and introduces an individual and interpersonal resilience measure developed for older adults which is grounded in the individual and family resilience literature. PMID:24787701

Linking extinction-colonization dynamics to genetic structure in a salamander metapopulation.

PubMed

Cosentino, Bradley J; Phillips, Christopher A; Schooley, Robert L; Lowe, Winsor H; Douglas, Marlis R

2012-04-22

Theory predicts that founder effects have a primary role in determining metapopulation genetic structure. However, ecological factors that affect extinction-colonization dynamics may also create spatial variation in the strength of genetic drift and migration. We tested the hypothesis that ecological factors underlying extinction-colonization dynamics influenced the genetic structure of a tiger salamander (Ambystoma tigrinum) metapopulation. We used empirical data on metapopulation dynamics to make a priori predictions about the effects of population age and ecological factors on genetic diversity and divergence among 41 populations. Metapopulation dynamics of A. tigrinum depended on wetland area, connectivity and presence of predatory fish. We found that newly colonized populations were more genetically differentiated than established populations, suggesting that founder effects influenced genetic structure. However, ecological drivers of metapopulation dynamics were more important than age in predicting genetic structure. Consistent with demographic predictions from metapopulation theory, genetic diversity and divergence depended on wetland area and connectivity. Divergence was greatest in small, isolated wetlands where genetic diversity was low. Our results show that ecological factors underlying metapopulation dynamics can be key determinants of spatial genetic structure, and that habitat area and isolation may mediate the contributions of drift and migration to divergence and evolution in local populations.

Multilevel Confirmatory Factor Analysis of a Scale Measuring Interagency Collaboration of Children's Mental Health Agencies

ERIC Educational Resources Information Center

Dedrick, Robert F.; Greenbaum, Paul E.

2011-01-01

Multilevel confirmatory factor analysis was used to evaluate the factor structure underlying the 12-item, three-factor "Interagency Collaboration Activities Scale" (ICAS) at the informant level and at the agency level. Results from 378 professionals (104 administrators, 201 service providers, and 73 case managers) from 32 children's mental health…

Establishing the Factor Structure of the 18-Item Version of the Junior Metacognitive Awareness Inventory

ERIC Educational Resources Information Center

Kim, Boyoung; Zyromski, Brett; Mariani, Melissa; Lee, Sang Min; Carey, John C.

2017-01-01

The Junior Metacognitive Awareness Inventory is a student self-report scale developed to correspond to a two-factor model of metacognition. Exploratory (N = 1,783) and confirmatory factor analysis (N = 942) were conducted using data from students in Grades 6 through 12 with results supporting two underlying factors corresponding to Knowledge and…

Differential Effects of the Factor Structure of the Wechsler Memory Scale-Revised on the Cortical Thickness and Complexity of Patients Aged Over 75 Years in a Memory Clinic Setting.

PubMed

Kinno, Ryuta; Shiromaru, Azusa; Mori, Yukiko; Futamura, Akinori; Kuroda, Takeshi; Yano, Satoshi; Murakami, Hidetomo; Ono, Kenjiro

2017-01-01

The Wechsler Memory Scale-Revised (WMS-R) is one of the internationally well-known batteries for memory assessment in a general memory clinic setting. Several factor structures of the WMS-R for patients aged under 74 have been proposed. However, little is known about the factor structure of the WMS-R for patients aged over 75 years and its neurological significance. Thus, we conducted exploratory factor analysis to determine the factor structure of the WMS-R for patients aged over 75 years in a memory clinic setting. Regional cerebral blood flow (rCBF) was calculated from single-photon emission computed tomography data. Cortical thickness and cortical fractal dimension, as the marker of cortical complexity, were calculated from high resolution magnetic resonance imaging data. We found that the four factors appeared to be the most appropriate solution to the model, including recognition memory, paired associate memory, visual-and-working memory, and attention as factors. Patients with mild cognitive impairments showed significantly higher factor scores for paired associate memory, visual-and-working memory, and attention than patients with Alzheimer's disease. Regarding the neuroimaging data, the factor scores for paired associate memory positively correlated with rCBF in the left pericallosal and hippocampal regions. Moreover, the factor score for paired associate memory showed most robust correlations with the cortical thickness in the limbic system, whereas the factor score for attention correlated with the cortical thickness in the bilateral precuneus. Furthermore, each factor score correlated with the cortical fractal dimension in the bilateral frontotemporal regions. Interestingly, the factor scores for the visual-and-working memory and attention selectively correlated with the cortical fractal dimension in the right posterior cingulate cortex and right precuneus cortex, respectively. These findings demonstrate that recognition memory, paired associate memory, visual-and-working memory, and attention can be crucial factors for interpreting the WMS-R results of elderly patients aged over 75 years in a memory clinic setting. Considering these findings, the results of WMS-R in elderly patients aged over 75 years in a memory clinic setting should be cautiously interpreted.

The Network Structure of Human Personality According to the NEO-PI-R: Matching Network Community Structure to Factor Structure

PubMed Central

Goekoop, Rutger; Goekoop, Jaap G.; Scholte, H. Steven

2012-01-01

Introduction Human personality is described preferentially in terms of factors (dimensions) found using factor analysis. An alternative and highly related method is network analysis, which may have several advantages over factor analytic methods. Aim To directly compare the ability of network community detection (NCD) and principal component factor analysis (PCA) to examine modularity in multidimensional datasets such as the neuroticism-extraversion-openness personality inventory revised (NEO-PI-R). Methods 434 healthy subjects were tested on the NEO-PI-R. PCA was performed to extract factor structures (FS) of the current dataset using both item scores and facet scores. Correlational network graphs were constructed from univariate correlation matrices of interactions between both items and facets. These networks were pruned in a link-by-link fashion while calculating the network community structure (NCS) of each resulting network using the Wakita Tsurumi clustering algorithm. NCSs were matched against FS and networks of best matches were kept for further analysis. Results At facet level, NCS showed a best match (96.2%) with a ‘confirmatory’ 5-FS. At item level, NCS showed a best match (80%) with the standard 5-FS and involved a total of 6 network clusters. Lesser matches were found with ‘confirmatory’ 5-FS and ‘exploratory’ 6-FS of the current dataset. Network analysis did not identify facets as a separate level of organization in between items and clusters. A small-world network structure was found in both item- and facet level networks. Conclusion We present the first optimized network graph of personality traits according to the NEO-PI-R: a ‘Personality Web’. Such a web may represent the possible routes that subjects can take during personality development. NCD outperforms PCA by producing plausible modularity at item level in non-standard datasets, and can identify the key roles of individual items and clusters in the network. PMID:23284713

Psychometric properties of the Intrinsic Motivation Inventory in a competitive sport setting: a confirmatory factor analysis.

PubMed

McAuley, E; Duncan, T; Tammen, V V

1989-03-01

The present study was designed to assess selected psychometric properties of the Intrinsic Motivation Inventory (IMI) (Ryan, 1982), a multidimensional measure of subjects' experience with regard to experimental tasks. Subjects (N = 116) competed in a basketball free-throw shooting game, following which they completed the IMI. The LISREL VI computer program was employed to conduct a confirmatory factor analysis to assess the tenability of a five factor hierarchical model representing four first-order factors or dimensions and a second-order general factor representing intrinsic motivation. Indices of model acceptability tentatively suggest that the sport data adequately fit the hypothesized five factor hierarchical model. Alternative models were tested but did not result in significant improvements in the goodness-of-fit indices, suggesting the proposed model to be the most accurate of the models tested. Coefficient alphas for the four dimensions and the overall scale indicated adequate reliability. The results are discussed with regard to the importance of accurate assessment of psychological constructs and the use of linear structural equations in confirming the factor structures of measures.

SFCHECK: a unified set of procedures for evaluating the quality of macromolecular structure-factor data and their agreement with the atomic model.

PubMed

Vaguine, A A; Richelle, J; Wodak, S J

1999-01-01

In this paper we present SFCHECK, a stand-alone software package that features a unified set of procedures for evaluating the structure-factor data obtained from X-ray diffraction experiments and for assessing the agreement of the atomic coordinates with these data. The evaluation is performed completely automatically, and produces a concise PostScript pictorial output similar to that of PROCHECK [Laskowski, MacArthur, Moss & Thornton (1993). J. Appl. Cryst. 26, 283-291], greatly facilitating visual inspection of the results. The required inputs are the structure-factor amplitudes and the atomic coordinates. Having those, the program summarizes relevant information on the deposited structure factors and evaluates their quality using criteria such as data completeness, structure-factor uncertainty and the optical resolution computed from the Patterson origin peak. The dependence of various parameters on the nominal resolution (d spacing) is also given. To evaluate the global agreement of the atomic model with the experimental data, the program recomputes the R factor, the correlation coefficient between observed and calculated structure-factor amplitudes and Rfree (when appropriate). In addition, it gives several estimates of the average error in the atomic coordinates. The local agreement between the model and the electron-density map is evaluated on a per-residue basis, considering separately the macromolecule backbone and side-chain atoms, as well as solvent atoms and heterogroups. Among the criteria are the normalized average atomic displacement, the local density correlation coefficient and the polymer chain connectivity. The possibility of computing these criteria using the omit-map procedure is also provided. The described software should be a valuable tool in monitoring the refinement procedure and in assessing structures deposited in databases.

Evaluating the Psychometric Properties of the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) among Italian Nurses: How Many Factors Must a Researcher Consider?

PubMed Central

Loera, Barbara; Converso, Daniela; Viotti, Sara

2014-01-01

Background The Maslach Burnout Inventory (MBI) is the mainstream measure for burnout. However, its psychometric properties have been questioned, and alternative measurement models of the inventory have been suggested. Aims Different models for the number of items and factors of the MBI-HSS, the version of the Inventory for the Human Service sector, were tested in order to identify the most appropriate model for measuring burnout in Italy. Methods The study dataset consisted of a sample of 925 nurses. Ten alternative models of burnout were compared using confirmatory factor analysis. The psychometric properties of items and reliability of the MBI-HSS subscales were evaluated. Results Item malfunctioning may confound the MBI-HSS factor structure. The analysis confirmed the factorial structure of the MBI-HSS with a three-dimensional, 20-item assessment. Conclusions The factorial structure underlying the MBI-HSS follows Maslach’s definition when items are reduced from the original 22 to a 20-item set. Alternative models, either with fewer items or with an increased number of latent dimensions in the burnout structure, do not yield better results to justify redefining the item set or theoretically revising the syndrome construct. PMID:25501716

A symptom level examination of the relationship between Cluster B personality disorders and patterns of criminality and violence in women.

PubMed

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.

A systematic review of risk and protective factors associated with family related violence in refugee families.

PubMed

Timshel, Isabelle; Montgomery, Edith; Dalgaard, Nina Thorup

2017-08-01

The current systematic review summarizes the evidence from studies examining the risk and protective factors associated with family related violence in refugee families. Data included 15 peer-reviewed qualitative and quantitative studies. In order to gain an overview of the identified risk and protective factors an ecological model was used to structure the findings. At the individual level, parental trauma experiences/mental illness, substance abuse and history of child abuse were found to be risk factors. Family level risk factors included parent-child interaction, family structure and family acculturation stress. At the societal level low socioeconomic status was identified as a risk factor. Cultural level risk factors included patriarchal beliefs. Positive parental coping strategies were a protective factor. An ecological analysis of the results suggests that family related violence in refugee families is a result of accumulating, multiple risk factors on the individual, familial, societal and cultural level. The findings suggest that individual trauma and exile related stress do not only affect the individual but have consequences at a family level. Thus, interventions targeting family related violence should not only include the individual, but the family. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Psychometric Structure of Items Assessing Autogynephilia.

PubMed

Hsu, Kevin J; Rosenthal, A M; Bailey, J Michael

2015-07-01

Autogynephilia, or paraphilic sexual arousal in a man to the thought or image of himself as a woman, manifests in a variety of different behaviors and fantasies. We examined the psychometric structure of 22 items assessing five known types of autogynephilia by subjecting them to exploratory factor analysis in a sample of 149 autogynephilic men. Results of oblique factor analyses supported the ability to distinguish five group factors with suitable items. Results of hierarchical factor analyses suggest that the five group factors were strongly underlain by a general factor of autogynephilia. Because the general factor accounted for a much greater amount of the total variance of the 22 items than did the group factors, the types of autogynephilia that a man has seem less important than the degree to which he has autogynephilia. However, the five types of autogynephilia remain conceptually useful because meaningful distinctions were found among them, including differential rates of endorsement and differential ability to predict other relevant variables like gender dysphoria. Factor-derived scales and subscales demonstrated good internal consistency reliabilities, and validity, with large differences found between autogynephilic men and heterosexual male controls. Future research should attempt to replicate our findings, which were mostly exploratory.

A Comparison of Intellectual Structure in Deaf and Hearing Children.

ERIC Educational Resources Information Center

Zwiebel, Abraham; Mertens, Donna M.

1985-01-01

Results of Snijders-Oomen Nonverbal Intelligence Test for 251 deaf and 101 hearing children in Israel included that (1) factor structure for total deaf group differs from that of hearing group; (2) differences in cognitive structure were evident by age level for deaf; and (3) differences exist between cognitive structures of hearing and deaf…

[Hierarchy structuring for mammography technique by interpretive structural modeling method].

PubMed

Kudo, Nozomi; Kurowarabi, Kunio; Terashita, Takayoshi; Nishimoto, Naoki; Ogasawara, Katsuhiko

2009-10-20

Participation in screening mammography is currently desired in Japan because of the increase in breast cancer morbidity. However, the pain and discomfort of mammography is recognized as a significant deterrent for women considering this examination. Thus quick procedures, sufficient experience, and advanced skills are required for radiologic technologists. The aim of this study was to make the point of imaging techniques explicit and to help understand the complicated procedure. We interviewed 3 technologists who were highly skilled in mammography, and 14 factors were retrieved by using brainstorming and the KJ method. We then applied Interpretive Structural Modeling (ISM) to the factors and developed a hierarchical concept structure. The result showed a six-layer hierarchy whose top node was explanation of the entire procedure on mammography. Male technologists were related to as a negative factor. Factors concerned with explanation were at the upper node. We gave attention to X-ray techniques and considerations. The findings will help beginners improve their skills.

The NEO Five-Factor Inventory: latent structure and relationships with dimensions of anxiety and depressive disorders in a large clinical sample.

PubMed

Rosellini, Anthony J; Brown, Timothy A

2011-03-01

The present study evaluated the latent structure of the NEO Five-Factor Inventory (NEO FFI) and relations between the five-factor model (FFM) of personality and dimensions of DSM-IV anxiety and depressive disorders (panic disorder, generalized anxiety disorder [GAD], obsessive-compulsive disorder, social phobia [SOC], major depressive disorder [MDD]) in a large sample of outpatients (N = 1,980). Exploratory structural equation modeling (ESEM) was used to show that a five-factor solution provided acceptable model fit, albeit with some poorly functioning items. Neuroticism demonstrated significant positive associations with all but one of the disorder constructs whereas Extraversion was inversely related to SOC and MDD. Conscientiousness was inversely related to MDD but demonstrated a positive relationship with GAD. Results are discussed in regard to potential revisions to the NEO FFI, the evaluation of other NEO instruments using ESEM, and clinical implications of structural paths between FFM domains and specific emotional disorders.

The NEO Five-Factor Inventory: Latent Structure and Relationships With Dimensions of Anxiety and Depressive Disorders in a Large Clinical Sample

PubMed Central

Rosellini, Anthony J.; Brown, Timothy A.

2017-01-01

The present study evaluated the latent structure of the NEO Five-Factor Inventory (NEO FFI) and relations between the five-factor model (FFM) of personality and dimensions of DSM-IV anxiety and depressive disorders (panic disorder, generalized anxiety disorder [GAD], obsessive–compulsive disorder, social phobia [SOC], major depressive disorder [MDD]) in a large sample of outpatients (N = 1,980). Exploratory structural equation modeling (ESEM) was used to show that a five-factor solution provided acceptable model fit, albeit with some poorly functioning items. Neuroticism demonstrated significant positive associations with all but one of the disorder constructs whereas Extraversion was inversely related to SOC and MDD. Conscientiousness was inversely related to MDD but demonstrated a positive relationship with GAD. Results are discussed in regard to potential revisions to the NEO FFI, the evaluation of other NEO instruments using ESEM, and clinical implications of structural paths between FFM domains and specific emotional disorders. PMID:20881102

Dynamic Structure Factor and Transport Coefficients of a Homogeneously Driven Granular Fluid in Steady State

NASA Astrophysics Data System (ADS)

Vollmayr-Lee, Katharina; Zippelius, Annette; Aspelmeier, Timo

2011-03-01

We study the dynamic structure factor of a granular fluid of hard spheres, driven into a stationary nonequilibrium state by balancing the energy loss due to inelastic collisions with the energy input due to driving. The driving is chosen to conserve momentum, so that fluctuating hydrodynamics predicts the existence of sound modes. We present results of computer simulations which are based on an event driven algorithm. The dynamic structure factor F (q , ω) is determined for volume fractions 0.05, 0.1 and 0.2 and coefficients of normal restitution 0.8 and 0.9. We observe sound waves, and compare our results for F (q , ω) with the predictions of generalized fluctuating hydrodynamics which takes into account that temperature fluctuations decay either diffusively or with a finite relaxation rate, depending on wave number and inelasticity. We determine the speed of sound and the transport coefficients and compare them to the results of kinetic theory. K.V.L. thanks the Institute of Theoretical Physics, University of Goettingen, for financial support and hospitality.

Psychopathological dimensions of depression: a factor study of the 17-item Hamilton depression rating scale in unipolar depressed outpatients.

PubMed

Pancheri, P; Picardi, A; Pasquini, M; Gaetano, P; Biondi, M

2002-02-01

Agreement on the factor structure of the Hamilton Depression Rating Scale (HDRS) has not been consistent among studies, and some investigators argued that the scale's factor structure is not reliable. This study aimed at shedding more light on this debated issue. We studied 186 adults with unipolar depression (Major Depressive Disorder, n=80; Dysthymic Disorder, n=71; Depressive Disorder Not Otherwise Specified, n=25; Adjustment Disorder, n=10). They had no comorbid DSM-IV axis I or axis II disorders, and had received no treatment with antidepressant drugs in the previous 2 months. The factor structure of the scale was studied using the principal factor method, followed by oblique rotation. Factor scores were computed for each subject using the regression method. Using the scree-test criterion for factor extraction, we obtained a four-factor solution, explaining 43.8% of total variance. The four factors extracted were identified as (1) somatic anxiety/somatization factor; (2) a psychic anxiety dimension; (3) a pure depressive dimension; and (4) anorexia factor. Patients with Major Depressive Disorder scored significantly higher than patients with other diagnoses on the pure depressive dimension. These results need to be replicated in different cultures, using analogous factoring techniques. Though not exhibiting factorial invariance in the stricter sense of the term, the 17-item HDRS did exhibit a relatively reliable factor structure. Our analysis provides further evidence that the scale is multidimensional. However, as long as the multidimensional character of the scale is taken into account the scale should be able to play a useful role in clinical research.

Measuring leader perceptions of school readiness for reforms: use of an iterative model combining classical and Rasch methods.

PubMed

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.

Nonlinear Response and Residual Strength of Damaged Stiffened Shells Subjected to Combined Loads

NASA Technical Reports Server (NTRS)

Starnes, James H., Jr.; Britt, Vicki O.; Rose, Cheryl A.; Rankin, Charles C.

1996-01-01

The results of an analytical study of the nonlinear response of stiffened fuselage shells with long cracks are presented. The shells are modeled with a hierarchical modeling strategy and analyzed with a nonlinear shell analysis code that maintains the shell in a nonlinear equilibrium state while the crack is grown. The analysis accurately accounts for global and local structural response phenomena. Fuselage skins, frames stringers and failsafe straps are included in the models. Results are presented for various combinations of internal pressure and mechanical bending, vertical shear and torsion loads, and the effects of crack orientation and location on the shell response are described. These results indicate that the nonlinear interaction between the in-plane stress resultants and the out-of-plane displacements near a crack can significantly affect the structural response of the shell, and the stress-intensity factors associated with a crack that are used to predict residual strength. The effects of representative combined loading conditions on the stress-intensity factors associated with a crack are presented. The effects of varying structural parameters on the stress-intensity factors associated with a crack, and on self-similar and non-self-similar crack-growth are also presented.

Structural Configuration Analysis of Crew Exploration Vehicle Concepts

NASA Technical Reports Server (NTRS)

Mukhopadhyay, V.

2006-01-01

Structural configuration modeling and finite element analysis of crew exploration vehicle (CEV) concepts are presented. In the structural configuration design approach, parametric solid models of the pressurized shell and tanks are developed. The CEV internal cabin pressure is same as in the International Space Station (ISS) to enable docking with the ISS without an intermediate airlock. Effects of this internal pressure load on the stress distribution, factor of safety, mass and deflections are investigated. Uniform 7 mm thick skin shell, 5 mm thick shell with ribs and frames, and isogrid skin construction options are investigated. From this limited study, the isogrid construction appears to provide most strength/mass ratio. Initial finite element analysis results on the service module tanks are also presented. These rapid finite element analyses, stress and factor of safety distribution results are presented as a part of lessons learned and to build up a structural mass estimation and sizing database for future technology support. This rapid structural analysis process may also facilitate better definition of the vehicles and components for rapid prototyping. However, these structural analysis results are highly conceptual and exploratory in nature and do not reflect current configuration designs being conducted at the program level by NASA and industry.

Latent structure modeling underlying theophylline tablet formulations using a Bayesian network based on a self-organizing map clustering.

PubMed

Yasuda, Akihito; Onuki, Yoshinori; Obata, Yasuko; Takayama, Kozo

2015-01-01

The "quality by design" concept in pharmaceutical formulation development requires the establishment of a science-based rationale and design space. In this article, we integrate thin-plate spline (TPS) interpolation, Kohonen's self-organizing map (SOM) and a Bayesian network (BN) to visualize the latent structure underlying causal factors and pharmaceutical responses. As a model pharmaceutical product, theophylline tablets were prepared using a standard formulation. We measured the tensile strength and disintegration time as response variables and the compressibility, cohesion and dispersibility of the pretableting blend as latent variables. We predicted these variables quantitatively using nonlinear TPS, generated a large amount of data on pretableting blends and tablets and clustered these data into several clusters using a SOM. Our results show that we are able to predict the experimental values of the latent and response variables with a high degree of accuracy and are able to classify the tablet data into several distinct clusters. In addition, to visualize the latent structure between the causal and latent factors and the response variables, we applied a BN method to the SOM clustering results. We found that despite having inserted latent variables between the causal factors and response variables, their relation is equivalent to the results for the SOM clustering, and thus we are able to explain the underlying latent structure. Consequently, this technique provides a better understanding of the relationships between causal factors and pharmaceutical responses in theophylline tablet formulation.

Uncovering the influence of social skills and psychosociological factors on pain sensitivity using structural equation modeling

PubMed Central

Tanaka, Yoichi; Nishi, Yuki; Nishi, Yuki; Osumi, Michihiro; Morioka, Shu

2017-01-01

Pain is a subjective emotional experience that is influenced by psychosociological factors such as social skills, which are defined as problem-solving abilities in social interactions. This study aimed to reveal the relationships among pain, social skills, and other psychosociological factors by using structural equation modeling. A total of 101 healthy volunteers (41 men and 60 women; mean age: 36.6±12.7 years) participated in this study. To evoke participants’ sense of inner pain, we showed them images of painful scenes on a PC screen and asked them to evaluate the pain intensity by using the visual analog scale (VAS). We examined the correlation between social skills and VAS, constructed a hypothetical model based on results from previous studies and the current correlational analysis results, and verified the model’s fit using structural equation modeling. We found significant positive correlations between VAS and total social skills values, as well as between VAS and the “start of relationships” subscales. Structural equation modeling revealed that the values for “start of relationships” had a direct effect on VAS values (path coefficient =0.32, p<0.01). In addition, the “start of relationships” had both a direct and an indirect effect on psychological factors via social support. The results indicated that extroverted people are more sensitive to inner pain and tend to get more social support and maintain a better psychological condition. PMID:28979161

Structure factors for tunneling ionization rates of molecules: General Hartree-Fock-based integral representation

NASA Astrophysics Data System (ADS)

Madsen, Lars Bojer; Jensen, Frank; Dnestryan, Andrey I.; Tolstikhin, Oleg I.

2017-07-01

In the leading-order approximation of the weak-field asymptotic theory (WFAT), the dependence of the tunneling ionization rate of a molecule in an electric field on its orientation with respect to the field is determined by the structure factor of the ionizing molecular orbital. The WFAT yields an expression for the structure factor in terms of a local property of the orbital in the asymptotic region. However, in general quantum chemistry approaches molecular orbitals are expanded in a Gaussian basis which does not reproduce their asymptotic behavior correctly. This hinders the application of the WFAT to polyatomic molecules, which are attracting increasing interest in strong-field physics. Recently, an integral-equation approach to the WFAT for tunneling ionization of one electron from an arbitrary potential has been developed. The structure factor is expressed in an integral form as a matrix element involving the ionizing orbital. The integral is not sensitive to the asymptotic behavior of the orbital, which resolves the difficulty mentioned above. Here, we extend the integral representation for the structure factor to many-electron systems treated within the Hartree-Fock method and show how it can be implemented on the basis of standard quantum chemistry software packages. We validate the methodology by considering noble-gas atoms and the CO molecule, for which accurate structure factors exist in the literature. We also present benchmark results for CO2 and for NH3 in the pyramidal and planar geometries.

Factor structure and criterion validity across the full scale and ten short forms of the CES-D among Chinese adolescents.

PubMed

Yang, Wenhui; Xiong, Ge; Garrido, Luis Eduardo; Zhang, John X; Wang, Meng-Cheng; Wang, Chong

2018-04-16

We systematically examined the factor structure and criterion validity across the full scale and 10 short forms of the Center for Epidemiological Studies Depression Scale (CES-D) with Chinese youth. Participants were 5,434 Chinese adolescents in Grades 7 to 12 who completed the full CES-D; 612 of them further completed a structured diagnostic interview with the major depressive disorder (MDD) module of the Kiddie Schedule for Affective Disorder and Schizophrenia for School-age Children. Using a split-sample approach, a series of 4-, 3-, 2-, and 1-factor models were tested using exploratory structural equation modeling and cross-validated using confirmatory factor analysis; the dimensionality was also evaluated by parallel analysis in conjunction with the scree test and aided by factor mixture analysis. The results indicated that a single-factor model of depression with a wording method factor fitted the data well, and was the optimal structure underlying the scores of the full and shortened CES-D. Additionally, receiver operating characteristic curve analyses for MDD case detection showed that the CES-D full-scale scores accurately detected MDD youth (area under the curve [AUC] = .84). Furthermore, the short-form scores produced comparable AUCs with the full scale (.82 to .85), as well as similar levels of sensitivity and specificity when using optimal cutoffs. These findings suggest that depression among Chinese adolescents can be adequately measured and screened for by a single-factor structure underlying the CES-D scores, and that the short forms provide a viable alternative to the full instrument. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Paths for Future Population Aging.

ERIC Educational Resources Information Center

Grigsby, Jill S.

Population aging refers to an entire age structure becoming older. The age structure of a population is the result of three basic processes: fertility, mortality, and migration. Age structures reflect both past effects and current patterns of these processes. At the town, city, or regional level, migration becomes an important factor in raising…

Structural Equation Analysis of the Wechsler Adult Intelligence Scale-Revised in a Normal Elderly Sample.

ERIC Educational Resources Information Center

Burton, D. Bradley; And Others

1994-01-01

A maximum-likelihood confirmatory factor analysis was performed by applying LISREL VII to the Wechsler Adult Intelligence Scale-Revised results of a normal elderly sample of 225 adults. Results indicate that a three-factor model fits best across all sample combinations. A mild gender effect is discussed. (SLD)

Factor structure of the Bulimia Test--Revised in college women from four ethnic groups.

PubMed

Fernandez, Senaida; Malcarne, Vanessa L; Malacrne, Vanessa L; Wilfley, Denise E; McQuaid, John

2006-07-01

The factor structure of the Bulimia Test--Revised (BULIT-R) was investigated using confirmatory factor analysis (CFA) and exploratory factor analysis (EFA). The sample consisted of 2,671 female college students (African American, Asian American, Caucasian American, and Latino American). Reliability coefficients were excellent across groups. African Americans scored significantly lower on the BULIT-R than Caucasian Americans. Across groups, CFA and EFA results suggest a six-factor solution is most appropriate. Consistent across groups were factors representing bingeing, body image, purging, and extreme weight loss behaviors, while few differences were observed across groups. These findings suggest that the measure is reliable and valid for use with diverse ethnic groups. Future research should focus on culturally salient psychological correlates of disordered eating in diverse ethnic groups.

Psychological factors related to donation behaviour among Chinese adults: results from a longitudinal investigation.

PubMed

Hu, H; Wang, T; Fu, Q

2017-10-01

Little is known about the psychological factors currently influencing blood donation in China. This study investigated the structure of psychological factors and their correlation with donation behaviour of adults in a transforming city in China over a 6-month period. Participants were recruited in Nanjing from May 2013 to April 2014. Preliminary focus group interviews with 102 participants were conducted to generate new items for a Theory of Planned Behaviour (TPB) questionnaire. The questionnaires were completed by 300 participants, and responses were subjected to factor analysis. We confirmed the resulting factorial structure with 861 respondents and examined the associations between these factors and donation behaviour during the next 6 months using structural equation modelling. Factor analysis and structural equation modelling of the data supported an extended TPB model with self-reported past donation behaviour as a covariate. After controlling for past donation behaviour, attitudes towards blood donation (β = 0·288), subjective norm (β = 0·149), self-efficacy (β = 0·199), trust in third-party health professionals (β = 0·237), mistrust towards blood collection agencies (BCAs) (β = -0·085) and traditional Chinese beliefs (β = -0·046) were significantly related to donation intention, whilst donation intention was positively (β = 0·212) associated with donation behaviour. These findings confirm that psychological factors such as attitudes are predictors of blood donation. Recruitment efforts using public information campaigns and interpersonal communications should focus on strengthening positive attitudes, increasing trust in third-party health professionals, elevating self-efficacy, changing traditional Chinese beliefs and relieving mistrust in blood collection agencies (BCAs). © 2017 British Blood Transfusion Society.

Assessing Management Support for Worksite Health Promotion: Psychometric Analysis of the Leading by Example (LBE) Instrument

PubMed Central

Della, Lindsay J.; DeJoy, David M.; Goetzel, Ron Z.; Ozminkowski, Ronald J.; Wilson, Mark G.

2009-01-01

Objective This paper describes the development of the Leading by Example (LBE) instrument. Methods Exploratory factor analysis was used to obtain an initial factor structure. Factor validity was evaluated using confirmatory factor analysis methods. Cronbach’s alpha and item-total correlations provided information on the reliability of the factor subscales. Results Four subscales were identified: business alignment with health promotion objectives; awareness of the health-productivity link; worksite support for health promotion; leadership support for health promotion. Factor by group comparisons revealed that the initial factor structure is effective in detecting differences in organizational support for health promotion across different employee groups Conclusions Management support for health promotion can be assessed using the LBE, a brief, self-report questionnaire. Researchers can use the LBE to diagnose, track, and evaluate worksite health promotion programs. PMID:18517097

Three-dimensional periodic dielectric structures having photonic Dirac points

DOEpatents

Bravo-Abad, Jorge; Joannopoulos, John D.; Soljacic, Marin

2015-06-02

The dielectric, three-dimensional photonic materials disclosed herein feature Dirac-like dispersion in quasi-two-dimensional systems. Embodiments include a face-centered cubic (fcc) structure formed by alternating layers of dielectric rods and dielectric slabs patterned with holes on respective triangular lattices. This fcc structure also includes a defect layer, which may comprise either dielectric rods or a dielectric slab with patterned with holes. This defect layer introduces Dirac cone dispersion into the fcc structure's photonic band structure. Examples of these fcc structures enable enhancement of the spontaneous emission coupling efficiency (the .beta.-factor) over large areas, contrary to the conventional wisdom that the .beta.-factor degrades as the system's size increases. These results enable large-area, low-threshold lasers; single-photon sources; quantum information processing devices; and energy harvesting systems.

Measuring safety climate in elderly homes.

PubMed

Yeung, Koon-Chuen; Chan, Charles C

2012-02-01

Provision of a valid and reliable safety climate dimension brings enormous benefits to the elderly home sector. The aim of the present study was to make use of the safety climate instrument developed by OSHC to measure the safety perceptions of employees in elderly homes such that the factor structure of the safety climate dimensions of elderly homes could be explored. In 2010, surveys by mustering on site method were administered in 27 elderly homes that had participated in the "Hong Kong Safe and Healthy Residential Care Home Accreditation Scheme" organized by the Occupational Safety and Health Council. Six hundred and fifty-one surveys were returned with a response rate of 54.3%. To examine the factor structure of safety climate dimensions in our study, an exploratory factor analysis (EFA) using principal components analysis method was conducted to identify the underlying factors. The results of the modified seven-factor's safety climate structure extracted from 35 items better reflected the safety climate dimensions of elderly homes. The Cronbach alpha range for this study (0.655 to 0.851) indicated good internal consistency among the seven-factor structure. Responses from managerial level, supervisory and professional level, and front-line staff were analyzed to come up with the suggestion on effective ways of improving the safety culture of elderly homes. The overall results showed that managers generally gave positive responses in the factors evaluated, such as "management commitment and concern to safety," "perception of work risks and some contributory influences," "safety communication and awareness," and "safe working attitude and participation." Supervisors / professionals, and frontline level staff on the other hand, have less positive responses. The result of the lowest score in the factors - "perception of safety rules and procedures" underlined the importance of the relevance and practicability of safety rules and procedures. The modified OSHC safety climate tool provided better evidence of structural validity and reliability for use by elderly homes' decision makers as an indicator of employee perception of safety in their institution. The findings and suggestions in the study provide useful information for the management, supervisors/professionals and frontline level staff to cultivate the safety culture in the elderly home sector. Most important, elderly homes can use the modified safety climate scale to identify problem areas in their safety culture and safety management practices and then target these for intervention. Copyright © 2012 Elsevier Ltd. All rights reserved.

Structural sensitivity of x-ray Bragg projection ptychography to domain patterns in epitaxial thin films

NASA Astrophysics Data System (ADS)

Hruszkewycz, S. O.; Zhang, Q.; Holt, M. V.; Highland, M. J.; Evans, P. G.; Fuoss, P. H.

2016-10-01

Bragg projection ptychography (BPP) is a coherent diffraction imaging technique capable of mapping the spatial distribution of the Bragg structure factor in nanostructured thin films. Here, we show that, because these images are projections, the structural sensitivity of the resulting images depends on the film thickness and the aspect ratio and orientation of the features of interest and that image interpretation depends on these factors. We model changes in contrast in the BPP reconstructions of simulated PbTiO3 ferroelectric thin films with meandering 180∘ stripe domains as a function of film thickness, discuss their origin, and comment on the implication of these factors on the design of BPP experiments of general nanostructured films.

Organizational Factors that Affect the Implementation of Information Technology: Perspectives of Middle Managers in Iran

PubMed Central

Barzekar, Hosein; Karami, Mahtab

2014-01-01

ABSTRACT Objective: to examine the organizational factors affecting the application of information technology in hospitals. Since the organizational factors are one of the most important determinants of successful projects, by understanding their impact and identifying them it can help planning a systematic IT implementation. Methods: In this cross-sectional descriptive study 110 middle managers were chosen from teaching hospitals. Structured questionnaire was used for the data collection. Results: There was a significant relationship between organization resource, organizational knowledge, process, management structure and values and goals with implementation of information technology. Conclusion: Findings showed that organizational factors had a considerable impact on implementation of information technology. Top managers must consider the important aspects of effective organizational factors. PMID:25568582

Factor Analysis of the Mystical Experience Questionnaire: A Study of Experiences Occasioned by the Hallucinogen Psilocybin

PubMed Central

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

The Psychometric Evaluation of the Connor-Davidson Resilience Scale Using a Chinese Military Sample

PubMed Central

Xie, Yuanjun; Peng, Li; Zuo, Xin; Li, Min

2016-01-01

This study examined the psychometric properties of the Connor-Davidson Resilience Scale (CD-RISC) with a Chinese military population with the aim of finding a suitable instrument to quantify resilience in Chinese military service members. The confirmatory factor analysis results did not support the factorial structure of the original or the Chinese community version of the CD-RISC, but the exploratory factor analysis results revealed a three-factor model (composed of Competency, Toughness, and Adaptability) that seemed to fit. Moreover, the repeat confirmatory factory analysis replicated the three-factor model. Additionally, the CD-RISC with a Chinese military sample exhibited appropriate psychometric properties, including internal consistency, test-retest reliability, and structural and concurrent validity. The revised CD-RISC with a Chinese military sample provides insight into the resilience measurement framework and could be a reliable and valid measurement for evaluating resilience in a Chinese military population. PMID:26859484

Fracture study of windshield glass panes

NASA Technical Reports Server (NTRS)

Yeh, H. Y.

1987-01-01

The major stresses which cause crack propagation in windshield glass panes are induced by bending moments which result from the pressure differentials across the panes. Hence the stress intensity factors for the finite plate with the semi-elliptical surface flaw and edge crack under the bending moments are examined. The results show that the crack growth will be upperbound if it is computed by using the stress intensity factor for the finite plate with the edge crack subjected to pure bending moments. Furthermore, if the ratio of crack depth to plate thickness, a/t, is within 0.3, the stress intensity factor can be conservatively assumed to be constant at the value of a/t equal to zero. A simplified equation to predict the structural life of glass panes is derived based on constant stress intensity factor. The accuracy of structural life is mainly dependent on how close the empirical parameter, m, can be estimated.

Dyadic confirmatory factor analysis of the inflammatory bowel disease family responsibility questionnaire.

PubMed

Greenley, Rachel Neff; Reed-Knight, Bonney; Blount, Ronald L; Wilson, Helen W

2013-09-01

Evaluate the factor structure of youth and maternal involvement ratings on the Inflammatory Bowel Disease Family Responsibility Questionnaire, a measure of family allocation of condition management responsibilities in pediatric inflammatory bowel disease. Participants included 251 youth aged 11-18 years with inflammatory bowel disease and their mothers. Item-level descriptive analyses, subscale internal consistency estimates, and confirmatory factor analyses of youth and maternal involvement were conducted using a dyadic data-analytic approach. Results supported the validity of 4 conceptually derived subscales including general health maintenance, social aspects, condition management tasks, and nutrition domains. Additionally, results indicated adequate support for the factor structure of a 21-item youth involvement measure and strong support for a 16-item maternal involvement measure. Additional empirical support for the validity of the Inflammatory Bowel Disease Family Responsibility Questionnaire was provided. Future research to replicate current findings and to examine the measure's clinical utility is warranted.

Optimization design of LED heat dissipation structure based on strip fins

NASA Astrophysics Data System (ADS)

Xue, Lingyun; Wan, Wenbin; Chen, Qingguang; Rao, Huanle; Xu, Ping

2018-03-01

To solve the heat dissipation problem of LED, a radiator structure based on strip fins is designed and the method to optimize the structure parameters of strip fins is proposed in this paper. The combination of RBF neural networks and particle swarm optimization (PSO) algorithm is used for modeling and optimization respectively. During the experiment, the 150 datasets of LED junction temperature when structure parameters of number of strip fins, length, width and height of the fins have different values are obtained by ANSYS software. Then RBF neural network is applied to build the non-linear regression model and the parameters optimization of structure based on particle swarm optimization algorithm is performed with this model. The experimental results show that the lowest LED junction temperature reaches 43.88 degrees when the number of hidden layer nodes in RBF neural network is 10, the two learning factors in particle swarm optimization algorithm are 0.5, 0.5 respectively, the inertia factor is 1 and the maximum number of iterations is 100, and now the number of fins is 64, the distribution structure is 8*8, and the length, width and height of fins are 4.3mm, 4.48mm and 55.3mm respectively. To compare the modeling and optimization results, LED junction temperature at the optimized structure parameters was simulated and the result is 43.592°C which approximately equals to the optimal result. Compared with the ordinary plate-fin-type radiator structure whose temperature is 56.38°C, the structure greatly enhances heat dissipation performance of the structure.

Back to the Consideration of Future Consequences Scale: time to reconsider?

PubMed

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.

Structure factor and radial distribution function of some liquid lanthanides using charged hard sphere

NASA Astrophysics Data System (ADS)

Patel, H. P.; Sonvane, Y. A.; Thakor, P. B.

2017-05-01

The structure factor S(q) and radial distribution function g(r) play vital role to study the various structural properties like electronic, dynamic, magnetic etc. The present paper deals with the structural studies of foresaid properties using our newly constructed parameter free model potential with the Charged Hard Sphere (CHS) approximation. The local field correction due to Sarkar et al. is used to incorporate exchange and correlation among the conduction electrons in dielectric screening. Here we report the S(q) and g(r) for some liquid lanthanides viz: La, Ce, Pr, Nd and Eu. Present computed results are compared with the available experimental data. Lastly we found that our parameter free model potential successfully explains the structural propertiesof4fliquidlanthanides.

Multifactorial genetic divergence processes drive the onset of speciation in an Amazonian fish

PubMed Central

Torrente-Vilara, Gislene; Quilodran, Claudio; Rodrigues da Costa Doria, Carolina; Montoya-Burgos, Juan I.

2017-01-01

Understanding the processes that drive population genetic divergence in the Amazon is challenging because of the vast scale, the environmental richness and the outstanding biodiversity of the region. We addressed this issue by determining the genetic structure of the widespread Amazonian common sardine fish Triportheus albus (Characidae). We then examined the influence, on this species, of all previously proposed population-structuring factors, including isolation-by-distance, isolation-by-barrier (the Teotônio Falls) and isolation-by-environment using variables that describe floodplain and water characteristics. The population genetics analyses revealed an unusually strong structure with three geographical groups: Negro/Tapajós rivers, Lower Madeira/Central Amazon, and Upper Madeira. Distance-based redundancy analyses showed that the optimal model for explaining the extreme genetic structure contains all proposed structuring factors and accounts for up to 70% of the genetic structure. We further quantified the contribution of each factor via a variance-partitioning analysis. Our results demonstrate that multiple factors, often proposed as individual drivers of population divergence, have acted in conjunction to divide T. albus into three genetic lineages. Because the conjunction of multiple long-standing population-structuring processes may lead to population reproductive isolation, that is, the onset of speciation, we suggest that the multifactorial population-structuring processes highlighted in this study could account for the high speciation rate characterising the Amazon Basin. PMID:29261722

Modeling the structure of the attitudes and belief scale 2 using CFA and bifactor approaches: Toward the development of an abbreviated version.

PubMed

Hyland, Philip; Shevlin, Mark; Adamson, Gary; Boduszek, Daniel

2014-01-01

The Attitudes and Belief Scale-2 (ABS-2: DiGiuseppe, Leaf, Exner, & Robin, 1988. The development of a measure of rational/irrational thinking. Paper presented at the World Congress of Behavior Therapy, Edinburg, Scotland.) is a 72-item self-report measure of evaluative rational and irrational beliefs widely used in Rational Emotive Behavior Therapy research contexts. However, little psychometric evidence exists regarding the measure's underlying factor structure. Furthermore, given the length of the ABS-2 there is a need for an abbreviated version that can be administered when there are time demands on the researcher, such as in clinical settings. This study sought to examine a series of theoretical models hypothesized to represent the latent structure of the ABS-2 within an alternative models framework using traditional confirmatory factor analysis as well as utilizing a bifactor modeling approach. Furthermore, this study also sought to develop a psychometrically sound abbreviated version of the ABS-2. Three hundred and thirteen (N = 313) active emergency service personnel completed the ABS-2. Results indicated that for each model, the application of bifactor modeling procedures improved model fit statistics, and a novel eight-factor intercorrelated solution was identified as the best fitting model of the ABS-2. However, the observed fit indices failed to satisfy commonly accepted standards. A 24-item abbreviated version was thus constructed and an intercorrelated eight-factor solution yielded satisfactory model fit statistics. Current results support the use of a bifactor modeling approach to determining the factor structure of the ABS-2. Furthermore, results provide empirical support for the psychometric properties of the newly developed abbreviated version.

German Validation of the Conners 3® Rating Scales for Parents, Teachers, and Children.

PubMed

Christiansen, Hanna; Hirsch, Oliver; Drechsler, Renate; Wanderer, Sina; Knospe, Eva-Lotte; Günther, Thomas; Lidzba, Karen

2016-01-01

Attention-deficit/hyperactivity disorder (ADHD) rating scales such as the Conners’ Rating Scales (CRS) are valuable adjuncts for diagnosis, since they offer parent, teacher, and self-ratings of children susceptible for ADHD. Even though the scales are widely used internationally, cross-cultural comparability has rarely been verified, and culture and language invariance have only been presumed. The Conners 3(®) rating scales are the updated version of the CRS, though hardly any studies report the psychometric properties apart from the results published in the test edition itself. To our knowledge there are no studies on the various adaptations of the Conners 3(®) in other languages. The German translations of the Conners 3(®) were completed by 745 children, 953 parents, and 741 teachers (children’s age range: 6–18 years, mean: 11.74 years of age). Exploratory and confirmatory factor analyses on content scale items were conducted to obtain the factor structure for the German version and to replicate the factor structure of the original American models. Cronbach’s α was calculated to establish internal consistency. The exploratory analyses for the German model resulted in factor structures globally different from the American model, though confirmatory analyses revealed very good model fi ts with highly satisfying Cronbach’s αs. We were able to provide empirical evidence for the subscale Inattention which had only hypothetically been derived by Conners (2008). Even though the exploratory analyses resulted in different factor structures, the confirmatory analyses have such excellent psychometric properties that use of the German adaptation of the Conners 3(®) is justifi ed in international multicenter studies.

Dynamic of Change in Pathological Personality Trait Dimensions: A Latent Change Analysis Among at-Risk Women

PubMed Central

Barbot, Baptiste; Hunter, Scott R.; Grigorenko, Elena L.; Luthar, Suniya S.

2012-01-01

This study explores longitudinally a four-factor structure of pathological personality trait dimensions (PPTDs) to examine both its structural stability and intra-individual changes among PPTDs over time. Personality Disorder (PD) scales of the Millon Clinical Multiaxial Inventory-III were administered to 361 low-income women with various psychiatric conditions (drug dependence, depression), who were followed in a two-wave study over 5-years. Cross-sectional and longitudinal factor analyses outlined a robust factorial structure of PPTDs, extrinsically invariant over time, representing Negative Emotionality, Introversion, Antagonism and Impulsivity. Despite moderate rank-order stability in the PPTDs, results also indicated substantial intra-individual variability in the degree and direction of change, consistent with trajectories of change in participants’ clinical diagnoses. Results are discussed in light of current debates on the structure and dynamic of pathological personality. PMID:23710108

An Exploratory Factor Analysis of Coping Styles and Relationship to Depression Among a Sample of Homeless Youth.

PubMed

Brown, Samantha M; Begun, Stephanie; Bender, Kimberly; Ferguson, Kristin M; Thompson, Sanna J

2015-10-01

The extent to which measures of coping adequately capture the ways that homeless youth cope with challenges, and the influence these coping styles have on mental health outcomes, is largely absent from the literature. This study tests the factor structure of the Coping Scale using Exploratory Factor Analysis (EFA) and then investigates the relationship between coping styles and depression using hierarchical logistic regression with data from 201 homeless youth. Results of the EFA indicate a 3-factor structure of coping, which includes active, avoidant, and social coping styles. Results of the hierarchical logistic regression show that homeless youth who engage in greater avoidant coping are at increased risk of meeting criteria for major depressive disorder. Findings provide insight into the utility of a preliminary tool for assessing homeless youths' coping styles. Such assessment may identify malleable risk factors that could be addressed by service providers to help prevent mental health problems.

The crystal structure of a multifunctional protein: phosphoglucose isomerase/autocrine motility factor/neuroleukin.

PubMed

Sun, Y J; Chou, C C; Chen, W S; Wu, R T; Meng, M; Hsiao, C D

1999-05-11

Phosphoglucose isomerase (PGI) plays a central role in both the glycolysis and the gluconeogenesis pathways. We present here the complete crystal structure of PGI from Bacillus stearothermophilus at 2.3-A resolution. We show that PGI has cell-motility-stimulating activity on mouse colon cancer cells similar to that of endogenous autocrine motility factor (AMF). PGI can also enhance neurite outgrowth on neuronal progenitor cells similar to that observed for neuroleukin. The results confirm that PGI is neuroleukin and AMF. PGI has an open twisted alpha/beta structural motif consisting of two globular domains and two protruding parts. Based on this substrate-free structure, together with the previously published biological, biochemical, and modeling results, we postulate a possible substrate-binding site that is located within the domains' interface for PGI and AMF. In addition, the structure provides evidence suggesting that the top part of the large domain together with one of the protruding loops might participate in inducing the neurotrophic activity.

Joint refinement model for the spin resolved one-electron reduced density matrix of YTiO3 using magnetic structure factors and magnetic Compton profiles data.

PubMed

Gueddida, Saber; Yan, Zeyin; Kibalin, Iurii; Voufack, Ariste Bolivard; Claiser, Nicolas; Souhassou, Mohamed; Lecomte, Claude; Gillon, Béatrice; Gillet, Jean-Michel

2018-04-28

In this paper, we propose a simple cluster model with limited basis sets to reproduce the unpaired electron distributions in a YTiO 3 ferromagnetic crystal. The spin-resolved one-electron-reduced density matrix is reconstructed simultaneously from theoretical magnetic structure factors and directional magnetic Compton profiles using our joint refinement algorithm. This algorithm is guided by the rescaling of basis functions and the adjustment of the spin population matrix. The resulting spin electron density in both position and momentum spaces from the joint refinement model is in agreement with theoretical and experimental results. Benefits brought from magnetic Compton profiles to the entire spin density matrix are illustrated. We studied the magnetic properties of the YTiO 3 crystal along the Ti-O 1 -Ti bonding. We found that the basis functions are mostly rescaled by means of magnetic Compton profiles, while the molecular occupation numbers are mainly modified by the magnetic structure factors.

Investigation of the factor structure of the Wechsler Adult Intelligence Scale--Fourth Edition (WAIS-IV): exploratory and higher order factor analyses.

PubMed

Canivez, Gary L; Watkins, Marley W

2010-12-01

The present study examined the factor structure of the Wechsler Adult Intelligence Scale--Fourth Edition (WAIS-IV; D. Wechsler, 2008a) standardization sample using exploratory factor analysis, multiple factor extraction criteria, and higher order exploratory factor analysis (J. Schmid & J. M. Leiman, 1957) not included in the WAIS-IV Technical and Interpretation Manual (D. Wechsler, 2008b). Results indicated that the WAIS-IV subtests were properly associated with the theoretically proposed first-order factors, but all but one factor-extraction criterion recommended extraction of one or two factors. Hierarchical exploratory analyses with the Schmid and Leiman procedure found that the second-order g factor accounted for large portions of total and common variance, whereas the four first-order factors accounted for small portions of total and common variance. It was concluded that the WAIS-IV provides strong measurement of general intelligence, and clinical interpretation should be primarily at that level.

Probabilistic structural analysis methods of hot engine structures

NASA Technical Reports Server (NTRS)

Chamis, C. C.; Hopkins, D. A.

1989-01-01

Development of probabilistic structural analysis methods for hot engine structures is a major activity at Lewis Research Center. Recent activities have focused on extending the methods to include the combined uncertainties in several factors on structural response. This paper briefly describes recent progress on composite load spectra models, probabilistic finite element structural analysis, and probabilistic strength degradation modeling. Progress is described in terms of fundamental concepts, computer code development, and representative numerical results.

Influence of Psychosocial Factors and Habitual Behavior in Temporomandibular Disorder–Related Symptoms in a Working Population in Japan

PubMed Central

Nishiyama, Akira; Kino, Koji; Sugisaki, Masashi; Tsukagoshi, Kaori

2012-01-01

Background: The symptoms of temporomandibular disorders (TMD) are directly influenced by numerous factors, and it is thought that additional factors exert indirect influences. However, the relationships between TMD-related symptoms (TRS) and these contributing factors are largely unknown. Thus, the goal of the present study was to investigate influences on TRS in a working population by determining the prevalence of TRS, analyzing contributing factors, and determining their relative influences on TRS. Materials and Methods: The study subjects were 2203 adults who worked for a single company. Subjects completed a questionnaire assessing TRS, psychosocial factors (stress, anxiety, depressed mood, and chronic fatigue), tooth-contacting habit, and sleep bruxism-related morning symptoms, using a 5-point numeric rating scale. Our analysis proceeded in 2 phases. First, all variables of the descriptor were divided into parts by using an exploratory factor analysis. Second, this factorial structure was verified by using a confirmatory factor analysis with structural equation modeling. Results: Of 2203 employees, 362 reported experiencing TRS (16.4%). Structural equation modeling generated a final model with a goodness of fit index of 0.991, an adjusted goodness of fit index of 0.984, and a root mean square error of approximately 0.021. These indices indicate a strong structural model. The standardized path coefficients for “habitual behavioral factors and TRS,” “psychosocial factors and habitual behavioral factors,” “psychosocial factors and TRS,” and “gender and habitual behavior factors” were 0.48, 0.38, 0.14, and 0.18, respectively. Conclusions: Habitual behavioral factors exert a stronger effect on TRS than do psychosocial factors. PMID:23346261

Investigating the Theoretical Structure of the DAS-II Core Battery at School Age Using Bayesian Structural Equation Modeling

ERIC Educational Resources Information Center

Dombrowski, Stefan C.; Golay, Philippe; McGill, Ryan J.; Canivez, Gary L.

2018-01-01

Bayesian structural equation modeling (BSEM) was used to investigate the latent structure of the Differential Ability Scales-Second Edition core battery using the standardization sample normative data for ages 7-17. Results revealed plausibility of a three-factor model, consistent with publisher theory, expressed as either a higher-order (HO) or a…

Family-centered care in children with epilepsy: Evaluating the Measure of Processes of Care (MPOC-20).

PubMed

Joachim, Kariym C; Wilk, Piotr; Ryan, Bridget L; Speechley, Kathy N

2016-10-01

The objective was to test whether the five-domain structure of the Measure of Processes of Care (MPOC-20) was observed in a sample of children with epilepsy and, if not, to propose adaptations to improve its utility in this population. Data came from the Health-Related Quality of Life in Children with Epilepsy Study (HERQULES)-a multicenter prospective cohort study (n = 374) following children 4-12 years of age for 2 years after diagnosis. Confirmatory factor analysis (CFA) tested the applicability of the five domains/factors in a sample of children with epilepsy approximately 6 months following diagnosis (n = 311). Goodness-of-fit statistics were used to examine sources of ill model fit, and modification indices guided the model modification process where there was strong theoretical rationale for changes. The five-factor model described by the originators of the MPOC-20 was found to be inadmissible in children with epilepsy, with four of the five factors demonstrating high correlations (r > 0.85). Upon merging the intercorrelated factors, a two-factor solution with a mediocre fit emerged (Root Mean Square Error of Approximation (RMSEA) = 0.080, Comparative Fit Index (CFI) = 0.902, Standardized Root Mean Square Residual (SRMR) = 0.060). Modification indices identified four items as the source of poor model fit. Removing these four items and reperforming the CFA resulted in an adequate model fit and a revised 16-item MPOC (RMSEA = 0.057, CFI = 0.958, SRMR = 0.036). The two factors are "Family/Care Provider Interaction" and "Providing Information." Results suggest that the MPOC-16 better reflects family-centered care (FCC) in children with epilepsy than the original MPOC-20. The benefit of having fewer factors is that scoring is simpler and the interpretation of the results is easier. This was the first investigation of the factor structure of the MPOC-20 on a sample entirely composed of children with epilepsy. These results add to evidence that the factor structure (and how family-centered care is delivered and perceived) differs across treatment environments and treatment populations. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Scale-dependent variation in forest structures in naturally dynamic boreal forest landscapes

NASA Astrophysics Data System (ADS)

Kulha, Niko; Pasanen, Leena; De Grandpré, Louis; Kuuluvainen, Timo; Aakala, Tuomas

2017-04-01

Natural forest structures vary at multiple spatial scales. This variation reflects the occurrence of driving factors, such as disturbances and variation in soil or topography. To explore and understand the linkages of forest structural characteristics and factors driving their variation, we need to recognize how the structural characteristics vary in relation to spatial scale. This can be achieved by identifying scale-dependent features in forest structure within unmanaged forest landscapes. By identifying these features and examining their relationship with potential driving factors, we can better understand the dynamics of forest structural development. Here, we examine the spatial variation in forest structures at multiple spatial scales, utilizing data from old-growth boreal forests in two regions with contrasting disturbance regimes: northern Finland and north-eastern Québec, Canada ( 67° 45'N, 29° 36'E, 49° 39'N, 67° 55'W, respectively). The three landscapes (4 km2 each) in Finland are dominated by Pinus sylvestris and Picea abies, whereas the two landscapes in Québec are dominated by Abies balsamea and Picea mariana. Québec's forests are a subject to cyclic outbreaks of the eastern spruce budworm, causing extensive mortality especially in A. balsamea-dominated stands. In the Finnish landscapes, gap- to patch-scale disturbances due to tree senescence, fungi and wind, as well as infrequent surface fires in areas dominated by P. sylvestris, prevail. Owing to the differences in the species compositions and the disturbance regimes, we expect differing scales of variation between the landscapes. To quantify patterns of variation, we visually interpret stereopairs of recent aerial photographs. From the photographs, we collect information on forest canopy coverage, species composition and dead wood. For the interpretation, each 4 km2 plot is divided into 0.1ha square cells (4096 per plot). Interpretations are validated against field observations and compiled to raster maps. We analyze the raster maps with Bayesian scale space approach (iBSiZer), which aims in capturing credible variations at different spatial scales. As a result, we can detect structural entities (e.g. patches with higher canopy cover), which deviate credibly from their surroundings. The detected entities can further be linked to specific drivers. Our results show that the role of a particular driving factor varies in relation to spatial scale. For example, in the Finnish landscapes, topoedaphic factors exerted a stronger control on broad-scale forest structural characteristics, whereas recent disturbances (quantified as the amount of dead wood) appeared to play an important role in explaining the smaller scale variation of forest structures. Here, we showcase the methodology used in the detection of scale-dependent forest structural entities and present the results of our analysis of the spatial scales of variation in the natural boreal forest structures.

What are the Dominant Factors of Students’ Productive Skills in Construction Services?

NASA Astrophysics Data System (ADS)

Oroh, R. R.; S, Haris A.; Sugandi, R. M.; Isnandar

2018-02-01

The purpose of this study to determine the dominant factors of students’ productive skills in doing the work of concrete structures that fit the needs of construction services. Sample of the respondents is vocational high school students from several districts and cities in North Sulawesi, Indonesia. Data are obtained through the performance test instruments of student. Whereas, data analysis is performed using factor analysis. The result of this research show the dominant factors of the students’ productive skills in doing the work of concrete structures that is according to the need of construction services, namely: (a) factor the working of concrete casting consists of making scaffolding from good materials and conducting concrete casting according to working method; and (b) factor the working of concrete reinforcing consists of read the working drawings for concrete reinforcement and make the concrete formwork from good material. Some of the respondent’s students in doing some concrete structure work have done well, but not yet according to working drawings, working methods and technical specifications of the work. The learning is done in accordance with the competency-oriented school curriculum but the teaching materials given have not been maximized in accordance with the needs of productive skills required construction services industry. The results have an impact on the low absorption of graduates in the implementation of the construction services industry.

a Study of the Synchrotron Laue Method for Quantitative Crystal Structure Analysis.

NASA Astrophysics Data System (ADS)

Gomez de Anderez, Dora M.

1990-01-01

Available from UMI in association with The British Library. Quantitative crystal structure analyses have been carried out on small molecule crystals using synchrotron radiation and the Laue method. A variety of single crystal structure determinations and associated refinements are used and compared with the monochromatic analyses. The new molecular structure of 7-amino-5-bromo -4-methyl-2-oxo-1,2,3,4-tetrahidro-1, 6 -naphthyridine-8-carbonitrile (C_{10 }H_9ON_4 Br.H_2O) has been determined, first using monochromatic Mo Kalpha radiation and a four-circle diffractometer, then using synchrotron Laue diffraction photography. The structure refinements showed a R-factor of 4.97 and 14.0% for the Mo Kalpha and Laue data respectively. The molecular structure of (S)-2-chloro-2-fluoro-N-((S)-1-phenylethyl) ethanamide, (C_{10}H _{11}ClFNO), has been determined using the same crystal throughout for X-ray monochromatic analyses (Mo Kalpha and Cu K alpha) followed by synchrotron Laue data collection. The Laue and monochromatic data compare favourably. The R -factors (on F) were 6.23, 6.45 and 8.19% for the Mo K alpha, Cu Kalpha and Laue data sets respectively. The molecular structure of 3-(5-hydroxy-3-methyl-1-phenylpyrazol-4-yl)-1,3-diphenyl -prop- 2-en-1-one, (C_{25 }H_{20}N _2O_2) has been determined using the synchrotron Laue method. The results compare very well with Mo Kalpha monochromatic data. The R-factors (on F) were 4.60 and 5.29% for Mo Kalpha and Laue analysis respectively. The Laue method is assessed in locating the 20 hydrogen atoms in this structure. The structure analysis of the benzil compound ((C_6H_5 O.CO_2)) is carried out using the synchrotron Laue method firstly at room temperature and secondly at low temperature -114 ^circC. The structure shows an R-factor (on F) of 13.06% and 6.85% for each data set respectively. The synchrotron Laue method was used to collect data for ergocalciferol (Vitamin D_2). The same crystal was also used to record oscillation data with the synchrotron radiation monochromatic beam. A new molecular structure of (Dinitrato-(N,N ^'-dimethylethylene-diamine)copper(II)) has been determined using Mo Kalpha radiation on a four circle diffractometer. The refinement resulted in an R-factor (on F) of 4.06%.

A Study of the Synchrotron Laue Method for Quantitative Crystal Structure Analysis

NASA Astrophysics Data System (ADS)

Gomez de Anderez, Dora M.

1990-01-01

Quantitative crystal structure analyses have been carried out on small molecule crystals using synchrotron radiation and the Laue method. A variety of single crystal structure determinations and associated refinements are used and compared with the monochromatic analyses. The new molecular structure of 7-amino-5-bromo -4-methyl-2-oxo-1,2,3,4 -tetrahidro-1,6 -naphthyridine-8-carbonitrile (C_{10 }H_9ON_4 BrcdotH_2O) has been determined, first using monochromatic Mo K alpha radiation and a four-circle diffractometer, then using synchrotron Laue diffraction photography. The structure refinements showed an R-factor of 4.97 and 14.0% for the Mo Kalpha and Laue data respectively. The molecular structure of (S)-2-chloro-2-fluoro-N-((S)-1-phenylethyl) ethanamide, (C_{10}H _{11}ClFNO), has been determined using the same crystal throughout for X-ray monochromatic analyses (Mo Kalpha and Cu K alpha) followed by synchrotron Laue data collection. The Laue and monochromatic data compare favourably. The R -factors (on F) were 6.23, 6.45 and 8.19% for the Mo K alpha, Cu Kalpha and Laue data sets respectively. The molecular structure of 3-(5-hydroxy-3-methyl-1-phenylpyrazol-4-yl)-1,3-diphenyl -prop-2-en-1-one, (C_{25}H _{20}N_2 O_2) has been determined using the synchrotron Laue method. The results compare very well with Mo Kalpha monochromatic data. The R-factors (on F) were 4.60 and 5.29% for Mo Kalpha and Laue analyses respectively. The Laue method is assessed in locating the 20 hydrogen atoms in this structure. The structure analyses of the benzil compound ((C_6H_5 OcdotCO_2)) is carried out using the synchrotron Laue method firstly at room temperature and secondly at low temperature. The structure shows an R-factor (on F) of 13.06% and 6.85% for each data set respectively. The synchrotron Laue method was used to collect data for ergocalciferol (Vitamin D_2). The same crystal was also used to record oscillation data with the synchrotron radiation monochromatic beam. A new molecular structure of (Dinitrato-(N,N ^'-dimethylethylene-diamine)copper(II)) has been determined using Mo Kalpha radiation on a four circle diffractometer. The refinement resulted in an R-factor (on F) of 4.06%.

Genetics of inherited cardiocutaneous syndromes: a review

PubMed Central

Bardawil, Tara; Khalil, Samar; Bergqvist, Christina; Abbas, Ossama; Kibbi, Abdul Ghani; Bitar, Fadi; Nemer, Georges; Kurban, Mazen

2016-01-01

The life of a human being originates as a single cell which, under the influence of certain factors, divides sequentially into multiple cells that subsequently become committed to develop and differentiate into the different structures and organs. Alterations occurring early on in the development process may lead to fetal demise in utero. Conversely, abnormalities at later stages may result in structural and/or functional abnormalities of varying severities. The cardiovascular system and skin share certain developmental and structural factors; therefore, it is not surprising to find several inherited syndromes with both cardiac and skin manifestations. Here, we will review the overlapping pathways in the development of the skin and heart, as well as the resulting syndromes. We will also highlight several cutaneous clues that may help physicians screen and uncover cardiac anomalies that may be otherwise hidden and result in sudden cardiac death. PMID:27933191

Perceived Parental Attitudes of Gender Expansiveness: Development and Preliminary Factor Structure of a Self-Report Youth Questionnaire

PubMed Central

Hidalgo, Marco A.; Chen, Diane; Garofalo, Robert; Forbes, Catherine

2017-01-01

Abstract Purpose: Parental acceptance of gender identity/expression in lesbian, gay, bisexual, transgender, and queer/questioning (LGBTQ+) youth moderates the effects of minority stress on mental health outcomes. Given this association, mental health clinicians of gender-expansive adolescents often assess the degree to which these youth perceive their parents/primary caregivers as accepting or nonaffirming of their gender identity and expression. While existing measures may reliably assess youth's perceptions of general family support, no known tool aids in the assessment an adolescent's perceived parental support related to adolescent gender-expansive experiences. Methods: To provide both clinicians and researchers with an empirically derived tool, the current study used factor analysis to explore an underlying factor structure of a brief questionnaire developed by subject-matter experts and pertaining to multiple aspects of perceived parental support in gender-expansive adolescents and young adults. Respondents were gender-expansive adolescents and young adults seeking care in an interdisciplinary gender-health clinic within a pediatric academic medical center in the Midwestern United States. Results: Exploratory factor analysis resulted in a 14-item questionnaire comprised of two subscales assessing perceived parental nonaffirmation and perceived parental acceptance. Internal consistency and construct validity results provided support for this new questionnaire. Conclusion: This study provides preliminary evidence of the factor structure, reliability and validity of the Parental Attitudes of Gender Expansiveness Scale for Youth (PAGES-Y). These findings demonstrate both the clinical and research utility of the PAGES-Y, a tool that can yield a more nuanced understanding of family-related risk and protective factors in gender-expansive adolescents. PMID:29159312

Perceived Parental Attitudes of Gender Expansiveness: Development and Preliminary Factor Structure of a Self-Report Youth Questionnaire.

PubMed

Hidalgo, Marco A; Chen, Diane; Garofalo, Robert; Forbes, Catherine

2017-01-01

Purpose: Parental acceptance of gender identity/expression in lesbian, gay, bisexual, transgender, and queer/questioning (LGBTQ+) youth moderates the effects of minority stress on mental health outcomes. Given this association, mental health clinicians of gender-expansive adolescents often assess the degree to which these youth perceive their parents/primary caregivers as accepting or nonaffirming of their gender identity and expression. While existing measures may reliably assess youth's perceptions of general family support, no known tool aids in the assessment an adolescent's perceived parental support related to adolescent gender-expansive experiences. Methods: To provide both clinicians and researchers with an empirically derived tool, the current study used factor analysis to explore an underlying factor structure of a brief questionnaire developed by subject-matter experts and pertaining to multiple aspects of perceived parental support in gender-expansive adolescents and young adults. Respondents were gender-expansive adolescents and young adults seeking care in an interdisciplinary gender-health clinic within a pediatric academic medical center in the Midwestern United States. Results: Exploratory factor analysis resulted in a 14-item questionnaire comprised of two subscales assessing perceived parental nonaffirmation and perceived parental acceptance. Internal consistency and construct validity results provided support for this new questionnaire. Conclusion: This study provides preliminary evidence of the factor structure, reliability and validity of the Parental Attitudes of Gender Expansiveness Scale for Youth (PAGES-Y). These findings demonstrate both the clinical and research utility of the PAGES-Y, a tool that can yield a more nuanced understanding of family-related risk and protective factors in gender-expansive adolescents.

Structure-preserving and rank-revealing QR-factorizations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bischof, C.H.; Hansen, P.C.

1991-11-01

The rank-revealing QR-factorization (RRQR-factorization) is a special QR-factorization that is guaranteed to reveal the numerical rank of the matrix under consideration. This makes the RRQR-factorization a useful tool in the numerical treatment of many rank-deficient problems in numerical linear algebra. In this paper, a framework is presented for the efficient implementation of RRQR algorithms, in particular, for sparse matrices. A sparse RRQR-algorithm should seek to preserve the structure and sparsity of the matrix as much as possible while retaining the ability to capture safely the numerical rank. To this end, the paper proposes to compute an initial QR-factorization using amore » restricted pivoting strategy guarded by incremental condition estimation (ICE), and then applies the algorithm suggested by Chan and Foster to this QR-factorization. The column exchange strategy used in the initial QR factorization will exploit the fact that certain column exchanges do not change the sparsity structure, and compute a sparse QR-factorization that is a good approximation of the sought-after RRQR-factorization. Due to quantities produced by ICE, the Chan/Foster RRQR algorithm can be implemented very cheaply, thus verifying that the sought-after RRQR-factorization has indeed been computed. Experimental results on a model problem show that the initial QR-factorization is indeed very likely to produce RRQR-factorization.« less

Psychometric structure of the Chinese Multiethnic Adolescent Cultural Identity Questionnaire.

PubMed

Hu, Fa-Wen; Wang, Pei; Li, Li-Ju

2014-12-01

In this study, we used the Chinese Multiethnic Adolescent Cultural Identity Questionnaire (CMACIQ) and collected valid data from 1,036 participants to systematically examine the mental model of cultural identity in Chinese multiethnic adolescents. Exploratory factor analysis and structural equation modeling were performed on the data to discover the factor structure and dimensions of cultural identity. The psychometric properties of the scale were rigorously validated in 2,744 new multiethnic participants from 5 native ethnic groups in Yunnan province in China. The results indicated that CMACIQ had reasonable metric properties and good fit indices. The hierarchical model of cultural identity consisted of 2 second-order factors, Ethnic Cultural Identity and Mainstream Cultural Identity in School. The first higher order factor was composed of preference for ethnic things, ethnic acceptance, religious belief, and ethnic convention, while the second comprised 2 first-order factors, Social Norms and Dominant Culture. The potential application and limitations of CMACIQ are discussed. (c) 2014 APA, all rights reserved.

The Factor Structure of the Spiritual Well-Being Scale in Veterans Experienced Chemical Weapon Exposure.

PubMed

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.

Evaluations of the psychometric properties of the Recovery-Stress Questionnaire for Athletes among a sample of young French table tennis players.

PubMed

Martinent, Guillaume; Decret, Jean-Claude; Isoard-Gautheur, Sandrine; Filaire, Edith; Ferrand, Claude

2014-04-01

This study used confirmatory factor analyses (CFAs) among a sample of young French table tennis players to test: (a) original 19-factor structure, (b) 14-factor structure recently suggested in literature, and (c) hierarchical factor structure of the Recovery-Stress Questionnaire for Athletes (RESTQ-Sport). 148 table tennis players completed the RESTQ-Sport and other self-report questionnaires between one to five occasions with a delay of 1 mo. between each completion. Results of CFAs showed: (a) evidence for relative superiority of the original model in comparison to an alternative model recently proposed in literature, (b) a good fit of the data for the 67-item 17-factor model of the RESTQ-Sport, and (c) an acceptable fit of the data for the hierarchical model of the RESTQ-Sport. Correlations between RESTQ-Sport subscales and burnout and motivation subscales also provided evidence for criterion-related validity of the RESTQ-Sport. This study provided support for reliability and validity of the RESTQ-Sport.

Factor structure of essential social skills to be salespersons in retail market: implications for psychiatric rehabilitation.

PubMed

Cheung, Leo C C; Tsang, Hector W H

2005-12-01

This study continued the effort to apply social skills training to increase vocational outcomes of people with severe mental illness. We planned to identify factor structure of essential social skills necessary for mental health consumers who have a vocational preference to work as salesperson in retail market. Exploratory factor analysis of the results of a 26-item questionnaire survey suggested a five-factor solution: social skills when interacting with customers, problem-solving skills, knowledge and attitudes, flexibility, and skills for conflict prevention, which accounted for 65.1% of the total variance. With the factor solution, we developed a job-specific social skills training program (JSST) to help consumers who want to be salespersons. The structure and session design followed the basic format of a typical social skills training program. The way this JSST is to be used with the work-related social skills training model previously developed by the corresponding author to produce better vocational outcomes of consumers is suggested.

Developing the Next Generation Shell Buckling Design Factors and Technologies

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.

2012-01-01

NASA s Shell Buckling Knockdown Factor (SBKF) Project was established in the spring of 2007 by the NASA Engineering and Safety Center (NESC) in collaboration with the Constellation Program and Exploration Systems Mission Directorate. The SBKF project has the current goal of developing less-conservative, robust shell buckling design factors (a.k.a. knockdown factors) and design and analysis technologies for light-weight stiffened metallic launch vehicle (LV) structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s LV development and performance risks. In particular, it is expected that the results from this project will help reduce the reliance on testing, provide high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. The SBKF project objectives and approach used to develop and validate new design technologies are presented, and provide a glimpse into the future of design of the next generation of buckling-critical launch vehicle structures.

Crack growth induced by thermal-mechanical loading

NASA Astrophysics Data System (ADS)

John, R.; Hartman, G. A.; Gallagher, J. P.

1992-06-01

Advanced aerospace structures are often subjected to combined thermal and mechanical loads. The fracture-mechanics behavior of the structures may be altered by the thermal state existing around the crack. Hence, design of critical structural elements requires the knowledge of stress-intensity factors under both thermal and mechanical loads. This paper describes the development of an experimental technique to verify the thermal-stress-intensity factor generated by a temperature gradient around the crack. Thin plate specimens of a model material (AISI-SAE 1095 steel) were used for the heat transfer and thermal-mechanical fracture tests. Rapid thermal loading was achieved using high-intensity focused infrared spot heaters. These heaters were also used to generate controlled temperature rates for heat-transfer verification tests. The experimental results indicate that thermal loads can generate stress-intensity factors large enough to induce crack growth. The proposed thermal-stress-intensity factors appear to have the same effect as the conventional mechanical-stress-intensity factors with respect to fracture.

Assessment of the structural validity of the domestic violence healthcare providers’ survey questionnaire using a Nigerian sample

PubMed Central

John, Ime A; Lawoko, Stephen

2010-01-01

Abstract: Background: There has been increased advocacy to involve healthcare providers in the prevention of intimate partner violence (IPV) through screening for it in healthcare. Yet, only one in ten providers screen for IPV, suggesting barriers. Understanding the readiness of healthcare providers to screen for IPV is therefore paramount. The Domestic Violence Healthcare Provider Survey Scales (DVHPSS) is a previously validated, comprehensive scale to study readiness of healthcare providers to screen for IPV. However, an understanding of its usefulness in the Sub-Saharan African context remains elusive. The current study undertook to examine the structural validity of the DVHPSS in Nigeria. Methods: Exploratory factor analysis and Cronbach's Alpha were run to reveal the factorial structure and reliability of the instrument/subscales respectively. Established thresholds were used to determine significant factor loadings and alphas coefficient. Results: A six factor model emerged, with 2 factors similar to the original scale, another two differing slightly and a further two factors resulting from a splitting up of the original combination of victim/provider safety to having distinct victim and provider safety subscales. Conclusions: With slight modifications, the DVHPSS can be use to study IPV screening among Nigerian healthcare professionals. Introducing screening protocols could promote better understanding of crucial questions that were lost in the analysis. PMID:21483202

Psychometric properties of the Spanish version of the Adolescent Stress Questionnaire (ASQ-S).

PubMed

Lima, Juan F; Alarcón, Rafael; Escobar, Milagros; Fernández-Baena, F Javier; Muñoz, Ángela M; Blanca, María J

2017-10-01

The aim of this study was to develop a Spanish version of the Adolescent Stress Questionnaire and to examine its psychometric properties: factor structure, measurement invariance across samples, reliability, and concurrent validity. Participants consisted of 1,560 Spanish students between 12 and 18 years of age. The results support a structure based on 10 first-order factors (corresponding to stressors on the dimensions Home Life, School Performance, School Attendance, Romantic Relationships, Peer Pressure, Teacher Interaction, Future Uncertainty, School/Leisure Conflict, Financial Pressure, and Emerging Adult Responsibility) and 1 second-order factor that subsumes the first-order factors. This model was selected for measurement invariance testing because it showed good fit indexes and was more parsimonious than the first-order factor model. This structure was replicated across 2 independent samples from the same population, as well as across 3 age groups (early, middle, and late adolescence), showing acceptable fit for all groups. Internal consistency and test-retest reliability were adequate. Evidence of concurrent validity was provided by positive associations with measures of stress manifestations, anxiety, and depression, and by a negative association with life satisfaction. The results indicate that the Spanish version of the Adolescent Stress Questionnaire is a suitable tool for assessing stressors in Spanish adolescents. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545, USA; Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720, USA; Department of Haematology, University of Cambridge, Cambridge CB2 0XY, England

The PHENIX AutoBuild Wizard is a highly automated tool for iterative model-building, structure refinement and density modification using RESOLVE or TEXTAL model-building, RESOLVE statistical density modification, and phenix.refine structure refinement. Recent advances in the AutoBuild Wizard and phenix.refine include automated detection and application of NCS from models as they are built, extensive model completion algorithms, and automated solvent molecule picking. Model completion algorithms in the AutoBuild Wizard include loop-building, crossovers between chains in different models of a structure, and side-chain optimization. The AutoBuild Wizard has been applied to a set of 48 structures at resolutions ranging from 1.1 {angstrom} tomore » 3.2 {angstrom}, resulting in a mean R-factor of 0.24 and a mean free R factor of 0.29. The R-factor of the final model is dependent on the quality of the starting electron density, and relatively independent of resolution.« less

Structural, functional and evolutionary relationships between homing endonucleases and proteins from their host organisms

PubMed Central

Taylor, Gregory K.; Stoddard, Barry L.

2012-01-01

Homing endonucleases (HEs) are highly specific DNA-cleaving enzymes that are encoded by invasive DNA elements (usually mobile introns or inteins) within the genomes of phage, bacteria, archea, protista and eukaryotic organelles. Six unique structural HE families, that collectively span four distinct nuclease catalytic motifs, have been characterized to date. Members of each family display structural homology and functional relationships to a wide variety of proteins from various organisms. The biological functions of those proteins are highly disparate and include non-specific DNA-degradation enzymes, restriction endonucleases, DNA-repair enzymes, resolvases, intron splicing factors and transcription factors. These relationships suggest that modern day HEs share common ancestors with proteins involved in genome fidelity, maintenance and gene expression. This review summarizes the results of structural studies of HEs and corresponding proteins from host organisms that have illustrated the manner in which these factors are related. PMID:22406833

An examination of the psychometric structure of the Multidimensional Pain Inventory in temporomandibular disorder patients: a confirmatory factor analysis

PubMed Central

Andreu, Yolanda; Galdon, Maria J; Durá, Estrella; Ferrando, Maite; Pascual, Juan; Turk, Dennis C; Jiménez, Yolanda; Poveda, Rafael

2006-01-01

Background This paper seeks to analyse the psychometric and structural properties of the Multidimensional Pain Inventory (MPI) in a sample of temporomandibular disorder patients. Methods The internal consistency of the scales was obtained. Confirmatory Factor Analysis was carried out to test the MPI structure section by section in a sample of 114 temporomandibular disorder patients. Results Nearly all scales obtained good reliability indexes. The original structure could not be totally confirmed. However, with a few adjustments we obtained a satisfactory structural model of the MPI which was slightly different from the original: certain items and the Self control scale were eliminated; in two cases, two original scales were grouped in one factor, Solicitous and Distracting responses on the one hand, and Social activities and Away from home activities, on the other. Conclusion The MPI has been demonstrated to be a reliable tool for the assessment of pain in temporomandibular disorder patients. Some divergences to be taken into account have been clarified. PMID:17169143

Iterative model building, structure refinement and density modification with the PHENIX AutoBuild wizard

PubMed Central

Terwilliger, Thomas C.; Grosse-Kunstleve, Ralf W.; Afonine, Pavel V.; Moriarty, Nigel W.; Zwart, Peter H.; Hung, Li-Wei; Read, Randy J.; Adams, Paul D.

2008-01-01

The PHENIX AutoBuild wizard is a highly automated tool for iterative model building, structure refinement and density modification using RESOLVE model building, RESOLVE statistical density modification and phenix.refine structure refinement. Recent advances in the AutoBuild wizard and phenix.refine include automated detection and application of NCS from models as they are built, extensive model-completion algorithms and automated solvent-molecule picking. Model-completion algorithms in the AutoBuild wizard include loop building, crossovers between chains in different models of a structure and side-chain optimization. The AutoBuild wizard has been applied to a set of 48 structures at resolutions ranging from 1.1 to 3.2 Å, resulting in a mean R factor of 0.24 and a mean free R factor of 0.29. The R factor of the final model is dependent on the quality of the starting electron density and is relatively independent of resolution. PMID:18094468

Exploring Factors that Affect Purchase Intention of Athletic Team Merchandise

ERIC Educational Resources Information Center

Lee, Donghun; Trail, Galen T.; Lee, Cindy; Schoenstedt, Linda J.

2013-01-01

The purpose of this study was to test a structural model to determine which psychosocial constructs affected the purchase intention of athletic team merchandise (ATM). Results from the analyses indicated that the twelve-factor ATM model fit the data from collegiate athletic events well, explaining the various impact factors that lead to purchase…

The Self-Report Family Inventory: An Exploratory Factor Analysis

ERIC Educational Resources Information Center

Goodrich, Kristopher M.; Selig, James P.; Trahan, Don P., Jr.

2012-01-01

Researchers explored the factor structure of the Self-Report Family Inventory with a sample of heterosexual parents who have a son or daughter who self-identifies as lesbian, gay, or bisexual. Results suggest that a two-factor solution is appropriate. Research and clinical implications are offered. (Contains 1 figure and 2 tables.)

Confirmatory Factor Analysis of the WISC-IV in a Hospital Referral Sample

ERIC Educational Resources Information Center

Devena, Sarah E.; Gay, Catherine E.; Watkins, Marley W.

2013-01-01

Confirmatory factor analysis was used to determine the factor structure of the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) scores of 297 children referred to a children's hospital in the Southwestern United States. Results support previous findings that indicate the WISC-IV is best represented by a direct hierarchical…

Brief report: Assessing dispositional optimism in adolescence--factor structure and concurrent validity of the Life Orientation Test--Revised.

PubMed

Monzani, Dario; Steca, Patrizia; Greco, Andrea

2014-02-01

Dispositional optimism is an individual difference promoting psychosocial adjustment and well-being during adolescence. Dispositional optimism was originally defined as a one-dimensional construct; however, empirical evidence suggests two correlated factors in the Life Orientation Test - Revised (LOT-R). The main aim of the study was to evaluate the dimensionality of the LOT-R. This study is the first attempt to identify the best factor structure, comparing congeneric, two correlated-factor, and two orthogonal-factor models in a sample of adolescents. Concurrent validity was also assessed. The results demonstrated the superior fit of the two orthogonal-factor model thus reconciling the one-dimensional definition of dispositional optimism with the bi-dimensionality of the LOT-R. Moreover, the results of correlational analyses proved the concurrent validity of this self-report measure: optimism is moderately related to indices of psychosocial adjustment and well-being. Thus, the LOT-R is a useful, valid, and reliable self-report measure to properly assess optimism in adolescence. Copyright © 2013 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Factors influencing health care access perceptions and care-seeking behaviors of immigrant Latino sexual minority men and transgender individuals: Baseline findings from the HOLA intervention study

PubMed Central

Tanner, AE; Reboussin, BA; Mann, L; Ma, A; Song, E; Alonzo, J; Rhodes, SD

2014-01-01

Little is known about immigrant Latino sexual minorities' health seeking behaviors. This study examined factors associated with perceptions of access and actual care behaviors among this population in North Carolina. Methods A community-based participatory research partnership recruited 180 Latino sexual minority men and transgender individuals within preexisting social networks to participate in a sexual health intervention. Mixed-effects logistic regression models examined factors influencing health care access perceptions and use of services (HIV testing and routine check-ups). Results Results indicate that perceptions of access and actual care behaviors are low and affected by individual and structural factors, including: years living in NC, reported poor general health, perceptions of discrimination, micro-, meso-, and macro-level barriers, and residence in a Medically Underserved Area. Discussion To improve Latino sexual minority health, focus must be placed on multiple levels, individual characteristics (e.g., demographics), clinic factors (e.g., provider competence and clinic environment), and structural factors (e.g., discrimination). PMID:25418235

The factor structure and reliability of the Illness Attitude Scales in a student and a patient sample

PubMed Central

Crössmann, Alexander; Pauli, Paul

2006-01-01

Background The Illness Attitude Scales (IAS), designed by Kellner in 1986, assesses fears, beliefs, and attitudes associated with hypochondriasis and abnormal illness behaviour. However, its factor structure is, especially for translations of the IAS, not sufficiently explored. Thus, the present Study aimed to analyse the factor structure of the IAS in a German student and a patient population using exploratory factor analysis. Methods A mixed student (N = 296) and a mixed patient (N = 130) sample completed the IAS. The data was submitted to principal components analyses (PCA) with subsequent oblique rotations. From identified factor structures, scales were derived and submitted to reliability analyses as well as to a preliminary validity analysis. Results The PCA revealed a four-factor solution in the student sample: (1) fear of illness and death; (2) treatment experience; (3) hypochondriacal beliefs; and (4) effect of symptoms. In the patient sample, the data was best explained by a two-factor solution: (1) health related anxiety and (2) effect of symptoms and treatment experience. All scales reached good to acceptable reliability coefficients. The scales derived from the student sample and those derived from the patient sample were able to distinguish between pain patients and a matched group of normal controls. Conclusion Our data suggests that the IAS is in student samples best represented by a four factor-solution and in patient samples by a two-factor-solution. PMID:17067384

Probabilistic simulation of the human factor in structural reliability

NASA Astrophysics Data System (ADS)

Chamis, Christos C.; Singhal, Surendra N.

1994-09-01

The formal approach described herein computationally simulates the probable ranges of uncertainties for the human factor in probabilistic assessments of structural reliability. Human factors such as marital status, professional status, home life, job satisfaction, work load, and health are studied by using a multifactor interaction equation (MFIE) model to demonstrate the approach. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Subsequently performed probabilistic sensitivity studies assess the suitability of the MFIE as well as the validity of the whole approach. Results show that uncertainties range from 5 to 30 percent for the most optimistic case, assuming 100 percent for no error (perfect performance).

Probabilistic Simulation of the Human Factor in Structural Reliability

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Singhal, Surendra N.

1994-01-01

The formal approach described herein computationally simulates the probable ranges of uncertainties for the human factor in probabilistic assessments of structural reliability. Human factors such as marital status, professional status, home life, job satisfaction, work load, and health are studied by using a multifactor interaction equation (MFIE) model to demonstrate the approach. Parametric studies in conjunction with judgment are used to select reasonable values for the participating factors (primitive variables). Subsequently performed probabilistic sensitivity studies assess the suitability of the MFIE as well as the validity of the whole approach. Results show that uncertainties range from 5 to 30 percent for the most optimistic case, assuming 100 percent for no error (perfect performance).

Denaturation of collagen structures and their transformation under the physical and chemical effects

NASA Astrophysics Data System (ADS)

Ivankin, A.; Boldirev, V.; Fadeev, G.; Baburina, M.; Kulikovskii, A.; Vostrikova, N.

2017-11-01

The process of denaturation of collagen structures under the influence of physical and chemical factors play an important role in the manufacture of food technology and the production of drugs for medicine and cosmetology. The paper discussed the problem of the combined effects of heat treatment, mechanical dispersion and ultrasonic action on the structural changes of the animal collagen in the presence of weak protonated organic acids. Algorithm combined effects of physical and chemical factors as a result of the formation of the technological properties of products containing collagen has been shown.

Application of Exploratory Structural Equation Modeling to Evaluate the Academic Motivation Scale

ERIC Educational Resources Information Center

Guay, Frédéric; Morin, Alexandre J. S.; Litalien, David; Valois, Pierre; Vallerand, Robert J.

2015-01-01

In this research, the authors examined the construct validity of scores of the Academic Motivation Scale using exploratory structural equation modeling. Study 1 and Study 2 involved 1,416 college students and 4,498 high school students, respectively. First, results of both studies indicated that the factor structure tested with exploratory…

Exploring the Structure of Adaptive Behavior: Project Report Number 87-1.

ERIC Educational Resources Information Center

Bruininks, Robert H.; McGrew, Kevin

This report presents results from three research studies that were designed to explore both the definition and the structure of the adaptive behavior construct. The first study investigated the structure of adaptive behavior as a function of age, developmental level, and type of handicap through an exploratory factor analysis of both the…

Fault-tolerant control of large space structures using the stable factorization approach

NASA Technical Reports Server (NTRS)

Razavi, H. C.; Mehra, R. K.; Vidyasagar, M.

1986-01-01

Large space structures are characterized by the following features: they are in general infinite-dimensional systems, and have large numbers of undamped or lightly damped poles. Any attempt to apply linear control theory to large space structures must therefore take into account these features. Phase I consisted of an attempt to apply the recently developed Stable Factorization (SF) design philosophy to problems of large space structures, with particular attention to the aspects of robustness and fault tolerance. The final report on the Phase I effort consists of four sections, each devoted to one task. The first three sections report theoretical results, while the last consists of a design example. Significant results were obtained in all four tasks of the project. More specifically, an innovative approach to order reduction was obtained, stabilizing controller structures for plants with an infinite number of unstable poles were determined under some conditions, conditions for simultaneous stabilizability of an infinite number of plants were explored, and a fault tolerance controller design that stabilizes a flexible structure model was obtained which is robust against one failure condition.

Correlation of the fragility of metallic liquids with the high temperature structure, volume, and cohesive energy

NASA Astrophysics Data System (ADS)

Gangopadhyay, A. K.; Pueblo, C. E.; Dai, R.; Johnson, M. L.; Ashcraft, R.; Van Hoesen, D.; Sellers, M.; Kelton, K. F.

2017-04-01

The thermal expansion coefficients, structure factors, and viscosities of twenty-five equilibrium and supercooled metallic liquids have been measured using an electrostatic levitation (ESL) facility. The structure factor was measured at the Advanced Photon Source, Argonne, using the ESL. A clear connection between liquid fragility and structural and volumetric changes at high temperatures is established; the observed changes are larger for the more fragile liquids. It is also demonstrated that the fragility of metallic liquids is determined to a large extent by the cohesive energy and is, therefore, predictable. These results are expected to provide useful guidance in the future design of metallic glasses.

Development, factor structure and application of the Dog Obesity Risk and Appetite (DORA) questionnaire

PubMed Central

Smith, Stephen P.; O’Rahilly, Stephen; Wardle, Jane

2015-01-01

Background. Dogs are compelling models in which to study obesity since the condition shares many characteristics between humans and dogs. Differences in eating behaviour are recognised to contribute to obesity susceptibility in other species but this has not been systematically studied in dogs. Aim. To develop and validate an owner-reported measure of canine eating behaviour and owner or dog related factors which can alter the development of obesity. Further, to then test variation in food-motivation in dogs and its association with obesity and owner management. Methods. Owner interviews, a literature review and existing human appetite scales were used to identify relevant topics and generate items for the questionnaire. Following a pilot phase, a 75 item online questionnaire was distributed via social media. Responses from 302 dog/owner dyads were analysed and factor structure and descriptive statistics calculated. Results were compared with descriptions of dog behaviour and management from a subset of respondents during semi-structured interviews. The optimum questions were disseminated as a 34 item final questionnaire completed by 213 owners, with a subset of respondents repeating the questionnaire 3 weeks later to assess test–retest reliability. Results. Analysis of responses to the final questionnaire relating to 213 dog/owner dyads showed a coherent factor structure and good test–retest reliability. There were three dog factors (food responsiveness and satiety, lack of selectivity, Interest in food), four owner factors (owner motivation to control dog weight, owner intervention to control dog weight, restriction of human food, exercise taken) and two dog health factors (signs of gastrointestinal disease, current poor health). Eating behaviour differed between individuals and between breed groups. High scores on dog factors (high food-motivation) and low scores on owner factors (less rigorous control of diet/exercise) were associated with obesity. Owners of more highly food-motivated dogs exerted more control over their dogs’ food intake than those of less food-motivated dogs. Conclusions. The DORA questionnaire is a reliable and informative owner-reported measure of canine eating behaviour and health and management factors which can be associated with obesity development. The tool will be applicable to study of the canine obesity model and to clinical veterinarians. Results revealed eating behaviour to be similarly associated with obesity as exercise and owners giving titbits. PMID:26468435

Development, factor structure and application of the Dog Obesity Risk and Appetite (DORA) questionnaire.

PubMed

Raffan, Eleanor; Smith, Stephen P; O'Rahilly, Stephen; Wardle, Jane

2015-01-01

Background. Dogs are compelling models in which to study obesity since the condition shares many characteristics between humans and dogs. Differences in eating behaviour are recognised to contribute to obesity susceptibility in other species but this has not been systematically studied in dogs. Aim. To develop and validate an owner-reported measure of canine eating behaviour and owner or dog related factors which can alter the development of obesity. Further, to then test variation in food-motivation in dogs and its association with obesity and owner management. Methods. Owner interviews, a literature review and existing human appetite scales were used to identify relevant topics and generate items for the questionnaire. Following a pilot phase, a 75 item online questionnaire was distributed via social media. Responses from 302 dog/owner dyads were analysed and factor structure and descriptive statistics calculated. Results were compared with descriptions of dog behaviour and management from a subset of respondents during semi-structured interviews. The optimum questions were disseminated as a 34 item final questionnaire completed by 213 owners, with a subset of respondents repeating the questionnaire 3 weeks later to assess test-retest reliability. Results. Analysis of responses to the final questionnaire relating to 213 dog/owner dyads showed a coherent factor structure and good test-retest reliability. There were three dog factors (food responsiveness and satiety, lack of selectivity, Interest in food), four owner factors (owner motivation to control dog weight, owner intervention to control dog weight, restriction of human food, exercise taken) and two dog health factors (signs of gastrointestinal disease, current poor health). Eating behaviour differed between individuals and between breed groups. High scores on dog factors (high food-motivation) and low scores on owner factors (less rigorous control of diet/exercise) were associated with obesity. Owners of more highly food-motivated dogs exerted more control over their dogs' food intake than those of less food-motivated dogs. Conclusions. The DORA questionnaire is a reliable and informative owner-reported measure of canine eating behaviour and health and management factors which can be associated with obesity development. The tool will be applicable to study of the canine obesity model and to clinical veterinarians. Results revealed eating behaviour to be similarly associated with obesity as exercise and owners giving titbits.

Application of Bayesian networks in a hierarchical structure for environmental risk assessment: a case study of the Gabric Dam, Iran.

PubMed

Malekmohammadi, Bahram; Tayebzadeh Moghadam, Negar

2018-04-13

Environmental risk assessment (ERA) is a commonly used, effective tool applied to reduce adverse effects of environmental risk factors. In this study, ERA was investigated using the Bayesian network (BN) model based on a hierarchical structure of variables in an influence diagram (ID). ID facilitated ranking of the different alternatives under uncertainty that were then used to evaluate comparisons of the different risk factors. BN was used to present a new model for ERA applicable to complicated development projects such as dam construction. The methodology was applied to the Gabric Dam, in southern Iran. The main environmental risk factors in the region, presented by the Gabric Dam, were identified based on the Delphi technique and specific features of the study area. These included the following: flood, water pollution, earthquake, changes in land use, erosion and sedimentation, effects on the population, and ecosensitivity. These risk factors were then categorized based on results from the output decision node of the BN, including expected utility values for risk factors in the decision node. ERA was performed for the Gabric Dam using the analytical hierarchy process (AHP) method to compare results of BN modeling with those of conventional methods. Results determined that a BN-based hierarchical structure to ERA present acceptable and reasonable risk assessment prioritization in proposing suitable solutions to reduce environmental risks and can be used as a powerful decision support system for evaluating environmental risks.

The Spinal Cord Injury- Functional Index: Item Banks to Measure Physical Functioning of Individuals with Spinal Cord Injury

PubMed Central

Tulsky, David S.; Jette, Alan; Kisala, Pamela A.; Kalpakjian, Claire; Dijkers, Marcel P.; Whiteneck, Gale; Ni, Pengsheng; Kirshblum, Steven; Charlifue, Susan; Heinemann, Allen W.; Forchheimer, Martin; Slavin, Mary; Houlihan, Bethlyn; Tate, Denise; Dyson-Hudson, Trevor; Fyffe, Denise; Williams, Steve; Zanca, Jeanne

2012-01-01

Objective To develop a comprehensive set of patient reported items to assess multiple aspects of physical functioning relevant to the lives of people with spinal cord injury (SCI) and to evaluate the underlying structure of physical functioning. Design Cross-sectional Setting Inpatient and community Participants Item pools of physical functioning were developed, refined and field tested in a large sample of 855 individuals with traumatic spinal cord injury stratified by diagnosis, severity, and time since injury Interventions None Main Outcome Measure SCI-FI measurement system Results Confirmatory factor analysis (CFA) indicated that a 5-factor model, including basic mobility, ambulation, wheelchair mobility, self care, and fine motor, had the best model fit and was most closely aligned conceptually with feedback received from individuals with SCI and SCI clinicians. When just the items making up basic mobility were tested in CFA, the fit statistics indicate strong support for a unidimensional model. Similar results were demonstrated for each of the other four factors indicating unidimensional models. Conclusions Though unidimensional or 2-factor (mobility and upper extremity) models of physical functioning make up outcomes measures in the general population, the underlying structure of physical function in SCI is more complex. A 5-factor solution allows for comprehensive assessment of key domain areas of physical functioning. These results informed the structure and development of the SCI-FI measurement system of physical functioning. PMID:22609299

Reliability and validity analysis of modified Nursing Stress Scale for Indian population.

PubMed

Pathak, Vasundhara; Chakraborty, Tania; Mukhopadhyay, Suman

2013-01-01

The original Nursing Stress Scale (NSS) was structurally modified according to results of factorial analysis and a new scale was named as modified nursing stress scale (MNSS). This is the first study to modify and validate NSS for Indian nursing population. Factorial analysis showed different factor loading for two subscales and items were shifted according to their loading to provide a more meaningful structure. After relocation of Items 13, 14, and 15 into first factor, this factor was renamed as "emotional and painful conditions of patients" to provide a more appropriate name to the first factor. Items 24, 25, 26, 27, 28, and 29 were found to be distributed under two different factors; one of these two was renamed as "unpredictable changes" and another retained its original name (i.e., workload). This distribution was also supported by rational analysis. All other items were distributed under factors as in the original scale. Rest of the validity assessment was done with the modified scale. Thus, with minor changes in structure, the scale was found to have better content validity.

Factor structure and validation of the Attentional Control Scale.

PubMed

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.

The structure of PTSD symptoms according to DSM-5 and IDC-11 proposal: A multi-sample analysis.

PubMed

Cyniak-Cieciura, M; Staniaszek, K; Popiel, A; Pragłowska, E; Zawadzki, B

2017-07-01

Posttraumatic stress disorder (PTSD) symptoms structure is a subject of ongoing debate since its inclusion in DSM-III classification in 1980. Different research on PTSD symptoms structure proved the better fit of four-factor and five-factor models comparing to the one proposed by DSM-IV. With the publication of DSM-5 classification, which introduced significant changes to PTSD diagnosis, the question arises about the adequacy of the proposed criteria to the real structure of disorder symptoms. Recent analyses suggest that seven-factor hybrid model is the best reflection of symptoms structure proposed to date. At the same time, some researchers and ICD-11 classification postulate a simplification of PTSD diagnosis restricting it to only three core criteria and adding additional diagnostic unit of complex-PTSD. This research aimed at checking symptoms' structure according to well-known and supported four-, five-, six- and seven-factor models based on DSM-5 symptoms and the conceptualization proposed by the ICD-11 as well as examining the relation between PTSD symptoms categories with borderline personality disorder. Four different trauma populations were examined with self-reported Posttraumatic Diagnostic Scale for DSM-5 (PDS-5) measure. The results suggest that six- and seven-factor hybrid model as well as three-factor ICD-11 concept fits the data better than other models. The core PTSD symptoms were less related to borderline personality disorder than other, broader, symptoms categories only in one sample. Combination of ICD-11 simplified PTSD diagnosis with the more complex approach (e.g. basing on a seven-factor model) may be an attractive proposal for both scientists and practitioners, however does not necessarily lower its comorbidity with borderline personality disorder. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

The feeding practices and structure questionnaire: construction and initial validation in a sample of Australian first-time mothers and their 2-year olds

PubMed Central

2014-01-01

Background Early feeding practices lay the foundation for children’s eating habits and weight gain. Questionnaires are available to assess parental feeding but overlapping and inconsistent items, subscales and terminology limit conceptual clarity and between study comparisons. Our aim was to consolidate a range of existing items into a parsimonious and conceptually robust questionnaire for assessing feeding practices with very young children (<3 years). Methods Data were from 462 mothers and children (age 21–27 months) from the NOURISH trial. Items from five questionnaires and two study-specific items were submitted to a priori item selection, allocation and verification, before theoretically-derived factors were tested using Confirmatory Factor Analysis. Construct validity of the new factors was examined by correlating these with child eating behaviours and weight. Results Following expert review 10 factors were specified. Of these, 9 factors (40 items) showed acceptable model fit and internal reliability (Cronbach’s α: 0.61-0.89). Four factors reflected non-responsive feeding practices: ‘Distrust in Appetite’, ‘Reward for Behaviour’, ‘Reward for Eating’, and ‘Persuasive Feeding’. Five factors reflected structure of the meal environment and limits: ‘Structured Meal Setting’, ‘Structured Meal Timing’, ‘Family Meal Setting’, ‘Overt Restriction’ and ‘Covert Restriction’. Feeding practices generally showed the expected pattern of associations with child eating behaviours but none with weight. Conclusion The Feeding Practices and Structure Questionnaire (FPSQ) provides a new reliable and valid measure of parental feeding practices, specifically maternal responsiveness to children’s hunger/satiety signals facilitated by routine and structure in feeding. Further validation in more diverse samples is required. PMID:24898364

[Dimensional structure of the Brazilian version of the Scale of Satisfaction with Interpersonal Processes of General Medical Care].

PubMed

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.

The Structure of Character Strengths: Variable- and Person-Centered Approaches

PubMed Central

Najderska, Małgorzata; Cieciuch, Jan

2018-01-01

This article examines the structure of character strengths (Peterson and Seligman, 2004) following both variable-centered and person-centered approaches. We used the International Personality Item Pool-Values in Action (IPIP-VIA) questionnaire. The IPIP-VIA measures 24 character strengths and consists of 213 direct and reversed items. The present study was conducted in a heterogeneous group of N = 908 Poles (aged 18–78, M = 28.58). It was part of a validation project of a Polish version of the IPIP-VIA questionnaire. The variable-centered approach was used to examine the structure of character strengths on both the scale and item levels. The scale-level results indicated a four-factor structure that can be interpreted based on four of the five personality traits from the Big Five theory (excluding neuroticism). The item-level analysis suggested a slightly different and limited set of character strengths (17 not 24). After conducting a second-order analysis, a four-factor structure emerged, and three of the factors could be interpreted as being consistent with the scale-level factors. Three character strength profiles were found using the person-centered approach. Two of them were consistent with alpha and beta personality metatraits. The structure of character strengths can be described by using categories from the Five Factor Model of personality and metatraits. They form factors similar to some personality traits and occur in similar constellations as metatraits. The main contributions of this paper are: (1) the validation of IPIP-VIA conducted in variable-centered approach in a new research group (Poles) using a different measurement instrument; (2) introducing the person-centered approach to the study of the structure of character strengths. PMID:29515482

Factor Analysis of Persistent Post-Concussive Symptoms within a Military Sample with Blast Exposure

PubMed Central

Franke, L.M.; Czarnota, J.N.; Ketchum, J.M.; Walker, W.C.

2014-01-01

Objective To determine the factor structure of persistent post-concussive syndrome (PPCS) symptoms in a blast-exposed military sample and validate factors against objective and symptom measures. Setting Veterans Affairs medical center and military bases. Participants One hundred eighty-one service members and veterans with at least one significant exposure to blast during deployment within the two years prior to study enrollment. Design Confirmatory and exploratory factor analysis of the Rivermead Post-concussion Questionnaire (RPQ). Main Measures RPQ, PTSD Symptom Checklist-Civilian, Center for Epidemiologic Studies Depression inventory, Sensory Organization Test, Paced Auditory Serial Addition Test, California Verbal Learning Test, Delis-Kaplan Executive Function System subtests. Results The three-factor structure of PPCS was not confirmed. A four-factor structure was extracted, and factors were interpreted as reflecting emotional, cognitive, visual, and vestibular functions. All factors were associated with scores on psychological symptom inventories; visual and vestibular factors were also associated with balance performance. There was no significant association between the cognitive factor and neuropsychological performance, nor between a history of mTBI and factor scores. Conclusion Persistent post-concussive symptoms observed months after blast exposure seem to be related to four distinct forms of distress, but not to mTBI per se, with vestibular and visual factors possibly related to injury of sensory organs by blast. PMID:24695267

Dimensional Model for Estimating Factors influencing Childhood Obesity: Path Analysis Based Modeling

PubMed Central

Kheirollahpour, Maryam; Shohaimi, Shamarina

2014-01-01

The main objective of this study is to identify and develop a comprehensive model which estimates and evaluates the overall relations among the factors that lead to weight gain in children by using structural equation modeling. The proposed models in this study explore the connection among the socioeconomic status of the family, parental feeding practice, and physical activity. Six structural models were tested to identify the direct and indirect relationship between the socioeconomic status and parental feeding practice general level of physical activity, and weight status of children. Finally, a comprehensive model was devised to show how these factors relate to each other as well as to the body mass index (BMI) of the children simultaneously. Concerning the methodology of the current study, confirmatory factor analysis (CFA) was applied to reveal the hidden (secondary) effect of socioeconomic factors on feeding practice and ultimately on the weight status of the children and also to determine the degree of model fit. The comprehensive structural model tested in this study suggested that there are significant direct and indirect relationships among variables of interest. Moreover, the results suggest that parental feeding practice and physical activity are mediators in the structural model. PMID:25097878

Accurate optimization of amino acid form factors for computing small-angle X-ray scattering intensity of atomistic protein structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tong, Dudu; Yang, Sichun; Lu, Lanyuan

2016-06-20

Structure modellingviasmall-angle X-ray scattering (SAXS) data generally requires intensive computations of scattering intensity from any given biomolecular structure, where the accurate evaluation of SAXS profiles using coarse-grained (CG) methods is vital to improve computational efficiency. To date, most CG SAXS computing methods have been based on a single-bead-per-residue approximation but have neglected structural correlations between amino acids. To improve the accuracy of scattering calculations, accurate CG form factors of amino acids are now derived using a rigorous optimization strategy, termed electron-density matching (EDM), to best fit electron-density distributions of protein structures. This EDM method is compared with and tested againstmore » other CG SAXS computing methods, and the resulting CG SAXS profiles from EDM agree better with all-atom theoretical SAXS data. By including the protein hydration shell represented by explicit CG water molecules and the correction of protein excluded volume, the developed CG form factors also reproduce the selected experimental SAXS profiles with very small deviations. Taken together, these EDM-derived CG form factors present an accurate and efficient computational approach for SAXS computing, especially when higher molecular details (represented by theqrange of the SAXS data) become necessary for effective structure modelling.« less

Reliability, convergent validity and factor structure of the DASS-21 in a sample of Vietnamese adolescents

PubMed Central

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

Validating the cross-cultural factor structure and invariance property of the Insomnia Severity Index: evidence based on ordinal EFA and CFA.

PubMed

Chen, Po-Yi; Yang, Chien-Ming; Morin, Charles M

2015-05-01

The purpose of this study is to examine the factor structure of the Insomnia Severity Index (ISI) across samples recruited from different countries. We tried to identify the most appropriate factor model for the ISI and further examined the measurement invariance property of the ISI across samples from different countries. Our analyses included one data set collected from a Taiwanese sample and two data sets obtained from samples in Hong Kong and Canada. The data set collected in Taiwan was analyzed with ordinal exploratory factor analysis (EFA) to obtain the appropriate factor model for the ISI. After that, we conducted a series of confirmatory factor analyses (CFAs), which is a special case of the structural equation model (SEM) that concerns the parameters in the measurement model, to the statistics collected in Canada and Hong Kong. The purposes of these CFA were to cross-validate the result obtained from EFA and further examine the cross-cultural measurement invariance of the ISI. The three-factor model outperforms other models in terms of global fit indices in Taiwan's population. Its external validity is also supported by confirmatory factor analyses. Furthermore, the measurement invariance analyses show that the strong invariance property between the samples from different cultures holds, providing evidence that the ISI results obtained in different cultures are comparable. The factorial validity of the ISI is stable in different populations. More importantly, its invariance property across cultures suggests that the ISI is a valid measure of the insomnia severity construct across countries. Copyright © 2014 Elsevier B.V. All rights reserved.

PTSD's latent structure in Malaysian tsunami victims: assessing the newly proposed Dysphoric Arousal model.

PubMed

Armour, Cherie; Raudzah Ghazali, Siti; Elklit, Ask

2013-03-30

The underlying latent structure of Posttraumatic Stress Disorder (PTSD) is widely researched. However, despite a plethora of factor analytic studies, no single model has consistently been shown as superior to alternative models. The two most often supported models are the Emotional Numbing and the Dysphoria models. However, a recently proposed five-factor Dysphoric Arousal model has been gathering support over and above existing models. Data for the current study were gathered from Malaysian Tsunami survivors (N=250). Three competing models (Emotional Numbing/Dysphoria/Dysphoric Arousal) were specified and estimated using Confirmatory Factor Analysis (CFA). The Dysphoria model provided superior fit to the data compared to the Emotional Numbing model. However, using chi-square difference tests, the Dysphoric Arousal model showed a superior fit compared to both the Emotional Numbing and Dysphoria models. In conclusion, the current results suggest that the Dysphoric Arousal model better represents PTSD's latent structure and that items measuring sleeping difficulties, irritability/anger and concentration difficulties form a separate, unique PTSD factor. These results are discussed in relation to the role of Hyperarousal in PTSD's on-going symptom maintenance and in relation to the DSM-5. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

AB INITIO Molecular Dynamics Simulations on Local Structure and Electronic Properties in Liquid MgxBi1-x Alloys

NASA Astrophysics Data System (ADS)

Hao, Qing-Hai; You, Yu-Wei; Kong, Xiang-Shan; Liu, C. S.

2013-03-01

The microscopic structure and dynamics of liquid MgxBi1-x(x = 0.5, 0.6, 0.7) alloys together with pure liquid Mg and Bi metals were investigated by means of ab initio molecular dynamics simulations. We present results of structure properties including pair correlation function, structural factor, bond-angle distribution function and bond order parameter, and their composition dependence. The dynamical and electronic properties have also been studied. The structure factor and pair correlation function are in agreement with the available experimental data. The calculated bond-angle distribution function and bond order parameter suggest that the stoichiometric composition Mg3Bi2 exhibits a different local structure order compared with other concentrations, which help us understand the appearance of the minimum electronic conductivity at this composition observed in previous experiments.

Development of Equivalent Material Properties of Microbump for Simulating Chip Stacking Packaging

PubMed Central

Lee, Chang-Chun; Tzeng, Tzai-Liang; Huang, Pei-Chen

2015-01-01

A three-dimensional integrated circuit (3D-IC) structure with a significant scale mismatch causes difficulty in analytic model construction. This paper proposes a simulation technique to introduce an equivalent material composed of microbumps and their surrounding wafer level underfill (WLUF). The mechanical properties of this equivalent material, including Young’s modulus (E), Poisson’s ratio, shear modulus, and coefficient of thermal expansion (CTE), are directly obtained by applying either a tensile load or a constant displacement, and by increasing the temperature during simulations, respectively. Analytic results indicate that at least eight microbumps at the outermost region of the chip stacking structure need to be considered as an accurate stress/strain contour in the concerned region. In addition, a factorial experimental design with analysis of variance is proposed to optimize chip stacking structure reliability with four factors: chip thickness, substrate thickness, CTE, and E-value. Analytic results show that the most significant factor is CTE of WLUF. This factor affects microbump reliability and structural warpage under a temperature cycling load and high-temperature bonding process. WLUF with low CTE and high E-value are recommended to enhance the assembly reliability of the 3D-IC architecture. PMID:28793495

Extending the applicability of the Goldschmidt tolerance factor to arbitrary ionic compounds

PubMed Central

Sato, Toyoto; Takagi, Shigeyuki; Deledda, Stefano; Hauback, Bjørn C.; Orimo, Shin-ichi

2016-01-01

Crystal structure determination is essential for characterizing materials and their properties, and can be facilitated by various tools and indicators. For instance, the Goldschmidt tolerance factor (T) for perovskite compounds is acknowledged for evaluating crystal structures in terms of the ionic packing. However, its applicability is limited to perovskite compounds. Here, we report on extending the applicability of T to ionic compounds with arbitrary ionic arrangements and compositions. By focussing on the occupancy of constituent spherical ions in the crystal structure, we define the ionic filling fraction (IFF), which is obtained from the volumes of crystal structure and constituent ions. Ionic compounds, including perovskites, are arranged linearly by the IFF, providing consistent results with T. The linearity guides towards finding suitable unit cell and composition, thus tackling the main obstacle for determining new crystal structures. We demonstrate the utility of the IFF by solving the structure of three hydrides with new crystal structures. PMID:27032978

Extending the applicability of the Goldschmidt tolerance factor to arbitrary ionic compounds.

PubMed

Sato, Toyoto; Takagi, Shigeyuki; Deledda, Stefano; Hauback, Bjørn C; Orimo, Shin-ichi

2016-04-01

Crystal structure determination is essential for characterizing materials and their properties, and can be facilitated by various tools and indicators. For instance, the Goldschmidt tolerance factor (T) for perovskite compounds is acknowledged for evaluating crystal structures in terms of the ionic packing. However, its applicability is limited to perovskite compounds. Here, we report on extending the applicability of T to ionic compounds with arbitrary ionic arrangements and compositions. By focussing on the occupancy of constituent spherical ions in the crystal structure, we define the ionic filling fraction (IFF), which is obtained from the volumes of crystal structure and constituent ions. Ionic compounds, including perovskites, are arranged linearly by the IFF, providing consistent results with T. The linearity guides towards finding suitable unit cell and composition, thus tackling the main obstacle for determining new crystal structures. We demonstrate the utility of the IFF by solving the structure of three hydrides with new crystal structures.

[Confirmative study of a French version of the Exercise Dependence Scale-revised with a French population].

PubMed

Allegre, B; Therme, P

2008-10-01

Since the first writings on excessive exercise, there has been an increased interest in exercise dependence. One of the major consequences of this increased interest has been the development of several definitions and measures of exercise dependence. The work of Veale [Does primary exercise dependence really exist? In: Annet J, Cripps B, Steinberg H, editors. Exercise addiction: Motivation for participation in sport and exercise.Leicester, UK: Br Psychol Soc; 1995. p. 1-5.] provides an advance for the definition and measure of exercise dependence. These studies have adapted the DSM-IV criteria for substance dependence to measure exercise dependence. The Exercise Dependence Scale-Revised is based on these diagnostic criteria, which are: tolerance; withdrawal effects; intention effect; lack of control; time; reductions in other activities; continuance. Confirmatory factor analyses of EDS-R provided support to present a measurement model (21 items loaded in seven factors) of EDS-R (Comparative Fit Index=0.97; Root mean Square Error of Approximation=0.05; Tucker-Lewis Index=0.96). The aim of this study was to examine the psychometric properties of a French version of the EDS-R [Factorial validity and psychometric examination of the exercise dependence scale-revised. Meas Phys Educ Exerc Sci 2004;8(4):183-201.] to test the stability of the seven-factor model of the original version with a French population. A total of 516 half-marathoners ranged in age from 17 to 74 years old (Mean age=39.02 years, ET=10.64), with 402 men (77.9%) and 114 women (22.1%) participated in the study. The principal component analysis results in a six-factor structure, which accounts for 68.60% of the total variance. Because principal component analysis presents a six-factor structure differing from the original seven-factor structure, two models were tested, using confirmatory factor analysis. The first model is the seven-factor model of the original version of the EDS-R and the second is the model produced by the principal component analysis. The results of confirmatory factor analysis presented the original model (with a seven-factor structure) as a good model and fit indices were good (X(2)/ddl=2.89, Root Mean Square Error of Approximation (RMSEA)=0.061, Expected Cross Validation Index (ECVI)=1.20, Goodness-of-Fit Index (GFI)=0.92, Comparative Fit Index (CFI)=0.94, Standardized Root Mean Square (SRMS)=0.048). These results showed that the French version of EDS-R has an identical factor structure to the original. Therefore, the French version of EDS-R was an acceptable scale to measure exercise dependence and can be used on a French population.

On a fast calculation of structure factors at a subatomic resolution.

PubMed

Afonine, P V; Urzhumtsev, A

2004-01-01

In the last decade, the progress of protein crystallography allowed several protein structures to be solved at a resolution higher than 0.9 A. Such studies provide researchers with important new information reflecting very fine structural details. The signal from these details is very weak with respect to that corresponding to the whole structure. Its analysis requires high-quality data, which previously were available only for crystals of small molecules, and a high accuracy of calculations. The calculation of structure factors using direct formulae, traditional for 'small-molecule' crystallography, allows a relatively simple accuracy control. For macromolecular crystals, diffraction data sets at a subatomic resolution contain hundreds of thousands of reflections, and the number of parameters used to describe the corresponding models may reach the same order. Therefore, the direct way of calculating structure factors becomes very time expensive when applied to large molecules. These problems of high accuracy and computational efficiency require a re-examination of computer tools and algorithms. The calculation of model structure factors through an intermediate generation of an electron density [Sayre (1951). Acta Cryst. 4, 362-367; Ten Eyck (1977). Acta Cryst. A33, 486-492] may be much more computationally efficient, but contains some parameters (grid step, 'effective' atom radii etc.) whose influence on the accuracy of the calculation is not straightforward. At the same time, the choice of parameters within safety margins that largely ensure a sufficient accuracy may result in a significant loss of the CPU time, making it close to the time for the direct-formulae calculations. The impact of the different parameters on the computer efficiency of structure-factor calculation is studied. It is shown that an appropriate choice of these parameters allows the structure factors to be obtained with a high accuracy and in a significantly shorter time than that required when using the direct formulae. Practical algorithms for the optimal choice of the parameters are suggested.

Examination of the Brief Fear of Negative Evaluation Scale-Version 2 and the Brief Fear of Negative Evaluation Scale-Straightforward Items Factor Structure in a Sample of U.S. College Students

ERIC Educational Resources Information Center

Liu, Liu; Lowe, Patricia A.

2016-01-01

The current study examined the factor structure of the Brief Fear of Negative Evaluation-Straightforward Items (BFNE-S) and the Brief Fear of Negative Evaluation-Version 2 (BFNE-II) among 151 college students from the United States. Results indicated that the BFNE-S and the BFNE-II scores demonstrated excellent internal consistency reliability.…

Distortion of Local Atomic Structures in Amorphous Ge-Sb-Te Phase Change Materials

NASA Astrophysics Data System (ADS)

Hirata, A.; Ichitsubo, T.; Guan, P. F.; Fujita, T.; Chen, M. W.

2018-05-01

The local atomic structures of amorphous Ge-Sb-Te phase-change materials have yet to be clarified and the rapid crystal-amorphous phase change resulting in distinct optical contrast is not well understood. We report the direct observation of local atomic structures in amorphous Ge2Sb2Te5 using "local" reverse Monte Carlo modeling dedicated to an angstrom-beam electron diffraction analysis. The results corroborated the existence of local structures with rocksalt crystal-like topology that were greatly distorted compared to the crystal symmetry. This distortion resulted in the breaking of ideal octahedral atomic environments, thereby forming local disordered structures that basically satisfied the overall amorphous structure factor. The crystal-like distorted octahedral structures could be the main building blocks in the formation of the overall amorphous structure of Ge-Sb-Te.

The development of summary components for the Disablement in the Physically Active scale in collegiate athletes.

PubMed

Houston, Megan N; Hoch, Johanna M; Van Lunen, Bonnie L; Hoch, Matthew C

2015-11-01

The Disablement in the Physically Active scale (DPA) is a generic patient-reported outcome designed to evaluate constructs of disability in physically active populations. The purpose of this study was to analyze the DPA scale structure for summary components. Four hundred and fifty-six collegiate athletes completed a demographic form and the DPA. A principal component analysis (PCA) was conducted with oblique rotation. Factors with eigenvalues >1 that explained >5 % of the variance were retained. The PCA revealed a two-factor structure consistent with paradigms used to develop the original DPA. Items 1-12 loaded on Factors 1 and Items 13-16 loaded on Factor 2. Items 1-12 pertain to impairment, activity limitations, and participation restrictions. Items 13-16 address psychosocial and emotional well-being. Consideration of item content suggested Factor 1 concerned physical function, while Factor 2 concerned mental well-being. Thus, items clustered around Factor 1 and 2 were identified as physical (DPA-PSC) and mental (DPA-MSC) summary components, respectively. Together, the factors accounted for 65.1 % of the variance. The PCA revealed a two-factor structure for the DPA that resulted in DPA-PSC and DPA-MSC. Analyzing the DPA as separate constructs may provide distinct information that could help to prescribe treatment and rehabilitation strategies.

Influence factors and forecast of carbon emission in China: structure adjustment for emission peak

NASA Astrophysics Data System (ADS)

Wang, B.; Cui, C. Q.; Li, Z. P.

2018-02-01

This paper introduced Principal Component Analysis and Multivariate Linear Regression Model to verify long-term balance relationships between Carbon Emissions and the impact factors. The integrated model of improved PCA and multivariate regression analysis model is attainable to figure out the pattern of carbon emission sources. Main empirical results indicate that among all selected variables, the role of energy consumption scale was largest. GDP and Population follow and also have significant impacts on carbon emission. Industrialization rate and fossil fuel proportion, which is the indicator of reflecting the economic structure and energy structure, have a higher importance than the factor of urbanization rate and the dweller consumption level of urban areas. In this way, some suggestions are put forward for government to achieve the peak of carbon emissions.

Structural sensitivity of x-ray Bragg projection ptychography to domain patterns in epitaxial thin films

DOE PAGES

Hruszkewycz, S. O.; Zhang, Q.; Holt, M. V.; ...

2016-10-04

Bragg projection ptychography (BPP) is a coherent diffraction imaging technique capable of mapping the spatial distribution of the Bragg structure factor in nanostructured thin films. Here, we show that, because these images are projections, the structural sensitivity of the resulting images depends on the film thickness and the aspect ratio and orientation of the features of interest and that image interpretation depends on these factors. Lastly, we model changes in contrast in the BPP reconstructions of simulated PbTiO 3 ferroelectric thin films with meandering 180° stripe domains as a function of film thickness, discuss their origin, and comment on themore » implication of these factors on the design of BPP experiments of general nanostructured films.« less

Using the Karolinska Scales of Personality on male juvenile delinquents: relationships between scales and factor structure.

PubMed

Dåderman, Anna M; Hellström, Ake; Wennberg, Peter; Törestad, Bertil

2005-01-01

The aim of the present study was to investigate relationships between scales from the Karolinska Scales of Personality (KSP) and the factor structure of the KSP in a sample of male juvenile delinquents. The KSP was administered to a group of male juvenile delinquents (n=55, mean age 17 years; standard deviation=1.2) from four Swedish national correctional institutions for serious offenders. As expected, the KSP showed appropriate correlations between the scales. Factor analysis (maximum likelihood) arrived at a four-factor solution in this sample, which is in line with previous research performed in a non-clinical sample of Swedish males. More research is needed in a somewhat larger sample of juvenile delinquents in order to confirm the present results regarding the factor solution.

An Exploratory Factor Analysis of the Acquired Capability for Suicide Scale in Male Prison Inmates

PubMed Central

Smith, Phillip N.; Wolford, Caitlin; Mandracchia, Jon T.; Jahn, Danielle R.

2014-01-01

Prison inmates are exposed to a number of adverse conditions prior to and during incarceration that place them at risk for suicide. The interpersonal theory of suicide may prove useful in better understanding suicide in prisons, allowing for more effective prevention and treatment programs. However, no studies of the interpersonal theory have been conducted in prison populations. Further, there have been no studies examining the factor structure of the assessment of one of the theory’s main constructs: the acquired capability for suicide. The current study examined the factor structure of the Acquired Capability for Suicide Scale in a sample of male prison inmates. We found that a four-factor model provided the best statistical and conceptual fit; though, only three of these factors were meaningful with an additional method-factor. The three resulting factors were each associated with previous exposure to painful and provocative events, but none differentiated suicide attempter status. Results suggest that the interpersonal theory has promise in application to suicide in prison populations, but more work is needed to develop a self-report measure of acquired capability, particularly as it relates to prisoners. PMID:23230965

An exploratory factor analysis of the Acquired Capability for Suicide Scale in male prison inmates.

PubMed

Smith, Phillip N; Wolford-Clevenger, Caitlin; Mandracchia, Jon T; Jahn, Danielle R

2013-02-01

Prison inmates are exposed to a number of adverse conditions prior to and during incarceration that place them at risk for suicide. The interpersonal theory of suicide may prove useful in better understanding suicide in prisons, allowing for more effective prevention and treatment programs. However, no studies of the interpersonal theory have been conducted in prison populations. Further, there have been no studies examining the factor structure of the assessment of one of the theory's main constructs: the acquired capability for suicide. The current study examined the factor structure of the Acquired Capability for Suicide Scale in a sample of male prison inmates. We found that a 4-factor model provided the best statistical and conceptual fit, though only 3 of these factors were meaningful with an additional method-factor. The 3 resulting factors were each associated with previous exposure to painful and provocative events, but none differentiated suicide attempter status. Results suggest that the interpersonal theory has promise in application to suicide in prison populations, but more work is needed to develop a self-report measure of acquired capability, particularly as it relates to prisoners.

Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability

DOE PAGES

Yu, Xiqian; Hu, Enyuan; Bak, Seongmin; ...

2015-12-07

Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. Furthermore, we also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue. As a result, it is widely accepted that the thermal instability of themore » cathodes is one of the most critical factors in thermal runaway and related safety problems.« less

Structural properties of fracture haematoma: current status and future clinical implications.

PubMed

Wang, Xin; Friis, Thor; Glatt, Vaida; Crawford, Ross; Xiao, Yin

2017-10-01

Blood clots (haematomas) that form immediately following a bone fracture have been shown to be vital for the subsequent healing process. During the clotting process, a number of factors can influence the fibrin clot structure, such as fibrin polymerization, growth factor binding, cellular infiltration (including platelet retraction), protein concentrations and cytokines. The modulation of the fibrin clot structure within the fracture site has important clinical implications and could result in the development of multifunctional scaffolds that mimic the natural structure of a haematoma. Artificial haematoma structures such as these can be created from the patient's own blood and can therefore act as an ideal bone defect filling material for potential clinical application to accelerate bone regeneration. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Internal Stress Monitoring of In-Service Structural Steel Members with Ultrasonic Method

PubMed Central

Li, Zuohua; He, Jingbo; Teng, Jun; Wang, Ying

2016-01-01

Internal stress in structural steel members is an important parameter for steel structures in their design, construction, and service stages. However, it is hard to measure via traditional approaches. Among the existing non-destructive testing (NDT) methods, the ultrasonic method has received the most research attention. Longitudinal critically refracted (Lcr) waves, which propagate parallel to the surface of the material within an effective depth, have shown great potential as an effective stress measurement approach. This paper presents a systematic non-destructive evaluation method to determine the internal stress in in-service structural steel members using Lcr waves. Based on theory of acoustoelasticity, a stress evaluation formula is derived. Factor of stress to acoustic time difference is used to describe the relationship between stress and measurable acoustic results. A testing facility is developed and used to demonstrate the performance of the proposed method. Two steel members are measured by using the proposed method and the traditional strain gauge method for verification. Parametric studies are performed on three steel members and the aluminum plate to investigate the factors that influence the testing results. The results show that the proposed method is effective and accurate for determining stress in in-service structural steel members. PMID:28773347

Internal Stress Monitoring of In-Service Structural Steel Members with Ultrasonic Method.

PubMed

Li, Zuohua; He, Jingbo; Teng, Jun; Wang, Ying

2016-03-23

Internal stress in structural steel members is an important parameter for steel structures in their design, construction, and service stages. However, it is hard to measure via traditional approaches. Among the existing non-destructive testing (NDT) methods, the ultrasonic method has received the most research attention. Longitudinal critically refracted (Lcr) waves, which propagate parallel to the surface of the material within an effective depth, have shown great potential as an effective stress measurement approach. This paper presents a systematic non-destructive evaluation method to determine the internal stress in in-service structural steel members using Lcr waves. Based on theory of acoustoelasticity, a stress evaluation formula is derived. Factor of stress to acoustic time difference is used to describe the relationship between stress and measurable acoustic results. A testing facility is developed and used to demonstrate the performance of the proposed method. Two steel members are measured by using the proposed method and the traditional strain gauge method for verification. Parametric studies are performed on three steel members and the aluminum plate to investigate the factors that influence the testing results. The results show that the proposed method is effective and accurate for determining stress in in-service structural steel members.

Study on turbulent flow and heat transfer performance of tubes with internal fins in EGR cooler

NASA Astrophysics Data System (ADS)

Liu, Lin; Ling, Xiang; Peng, Hao

2015-07-01

In this paper, flow and heat transfer performances of the tubes with internal longitudinal fins in Exhaust Gas Recirculation (EGR ) cooler were investigated by three-dimension computation and experiment . Each test tube was a single-pipe structure, without inner tube. Three-dimension computation was performed to determine the thermal characteristics difference between the two kinds of tubes, that is, the tube with an inner solid staff as a blocked structure and the tube without the blocked structure. The effects of fin width and fin height on heat transfer and flow are examined. For proving the validity of numerical method, the calculated results were compared with corresponding experimental data. The tube-side friction factor and heat transfer coefficient were examined. As a result, the maximum deviations between the numerical results and the experimental data are approximately 5.4 % for friction factor and 8.6 % for heat transfer coefficient, respectively. It is found that two types of internally finned tubes enhance significantly heat transfer. The heat transfer of the tube with blocked structure is better, while the pressure drop of the tube without blocked structure is lower. The comprehensive performance of the unblocked tube is better to applied in EGR cooler.

Validation of the factor structure of the adolescent dissociative experiences scale in a sample of trauma-exposed detained youth.

PubMed

Kerig, Patricia K; Charak, Ruby; Chaplo, Shannon D; Bennett, Diana C; Armour, Cherie; Modrowski, Crosby A; McGee, Andrew B

2016-09-01

The inclusion of a dissociative subtype in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM–5 ) criteria for the diagnosis of posttraumatic stress disorder (PTSD) has highlighted the need for valid and reliable measures of dissociative symptoms across developmental periods. The Adolescent Dissociative Experiences Scale (A-DES) is 1 of the few measures validated for young persons, but previous studies have yielded inconsistent results regarding its factor structure. Further, research to date on the A-DES has been based upon nonclinical samples of youth or those without a known history of trauma. To address these gaps in the literature, the present study investigated the factor structure and construct validity of the A-DES in a sample of highly trauma-exposed youth involved in the juvenile justice system. A sample of 784 youth (73.7% boys) recruited from a detention center completed self-report measures of trauma exposure and the A-DES, a subset of whom (n = 212) also completed a measure of PTSD symptoms. Confirmatory factor analyses revealed a best fitting 3-factor structure comprised of depersonalization or derealization, amnesia, and loss of conscious control, with configural and metric invariance across gender. Logistic regression analyses indicated that the depersonalization or derealization factor effectively distinguished between those youth who did and did not likely meet criteria for a diagnosis of PTSD as well as those with PTSD who did and did not likely meet criteria for the dissociative subtype. These results provide support for the multidimensionality of the construct of posttraumatic dissociation and contribute to the understanding of the dissociative subtype of PTSD among adolescents. (PsycINFO Database Record PsycINFO Database Record (c) 2016 APA, all rights reserved

Exploration and confirmation of the latent variable structure of the Jefferson scale of empathy

PubMed Central

LaNoue, Marianna

2014-01-01

Objectives: To reaffirm the underlying components of the JSE by using exploratory factor analysis (EFA), and to confirm its latent variable structure by using confirmatory factor analysis (CFA). Methods Research participants included 2,612 medical students who entered Jefferson Medical College between 2002 and 2012. This sample was divided into two groups: Matriculants between 2002 and 2007 (n=1,380) and between 2008 and 2012 (n=1,232). Data for 2002-2007 matriculants were subjected to EFA (principal component factor extraction), and data for matriculants of 2008-2012 were used for CFA (structural equation modeling, and root mean square error for approximation). Results The EFA resulted in three factors: “perspective-taking,” “compassionate care” and “walking in patient’s shoes” replicating the 3-factor model reported in most of the previous studies. The CFA showed that the 3-factor model was an acceptable fit, thus confirming the latent variable structure emerged in the EFA. Corrected item-total score correlations for the total sample were all positive and statistically significant, ranging from 0.13 to 0.61 with a median of 0.44 (p<0.01). The item discrimination effect size indices (contrasting item mean scores for the top-third versus bottom-third JSE scorers) ranged from 0.50 to 1.4 indicating that the differences in item mean scores between top and bottom scorers on the JSE were of practical importance. Cronbach’s alpha coefficient of the JSE for the total sample was 0.80, ranging from 0.75 to 0.84 for matriculatnts of different years. Conclusions Findings provided further support for underlying constructs of the JSE, adding to its credibility. PMID:25341215

The Historical Loss Scale: Longitudinal measurement equivalence and prospective links to anxiety among North American indigenous adolescents.

PubMed

Armenta, Brian E; Whitbeck, Les B; Habecker, Patrick N

2016-01-01

Thoughts of historical loss (i.e., the loss of culture, land, and people as a result of colonization) are conceptualized as a contributor to the contemporary distress experienced by North American Indigenous populations. Although discussions of historical loss and related constructs (e.g., historical trauma) are widespread within the Indigenous literature, empirical efforts to understand the consequence of historical loss are limited, partially because of the lack of valid assessments. In this study we evaluated the longitudinal measurement properties of the Historical Loss Scale (HLS)-a standardized measure that was developed to systematically examine the frequency with which Indigenous individuals think about historical loss-among a sample of North American Indigenous adolescents. We also test the hypothesis that thoughts of historical loss can be psychologically distressing. Via face-to-face interviews, 636 Indigenous adolescents from a single cultural group completed the HLS and a measure of anxiety at 4 time-points, which were separated by 1- to 2-year intervals (Mage = 12.09 years, SD = .86, 50.0% girls at baseline). Responses to the HLS were explained well by 3-factor (i.e., cultural loss, loss of people, and cultural mistreatment) and second-order factor structures. Both of these factor structures held full longitudinal metric (i.e., factor loadings) and scalar (i.e., intercepts) equivalence. In addition, using the second-order factor structure, more frequent thoughts of historical loss were associated with increased anxiety. The identified 3-factor and second-order HLS structures held full longitudinal measurement equivalence. Moreover, as predicted, our results suggest that historical loss can be psychologically distressing for Indigenous adolescents. (c) 2016 APA, all rights reserved).

Factor Structure of ImPACT® in Adolescent Student Athletes.

PubMed

Gerrard, Paul B; Iverson, Grant L; Atkins, Joseph E; Maxwell, Bruce A; Zafonte, Ross; Schatz, Philip; Berkner, Paul D

2017-02-01

ImPACT ® (Immediate Post-Concussion Assessment and Cognitive Testing) is a computerized neuropsychological screening battery, which is widely used to measure the acute effects of sport-related concussion and to monitor recovery from injury. This study examined the factor structure of ImPACT ® in several samples of high school student athletes. We hypothesized that a 2-factor structure would be present in all samples. A sample of 4,809 adolescent student athletes was included, and subgroups with a history of treatment for headaches or a self-reported history of learning problems or attention-deficit hyperactivity disorder were analyzed separately. Exploratory principal axis factor analyses with Promax rotations were used. As hypothesized, both the combination of Verbal Memory and Visual Memory Composite scores loaded on one (Memory) factor, while Visual Motor Speed and Reaction Time loaded on a different (Speed) factor, in the total sample and in all subgroups. These results provide reasonably compelling evidence, across multiple samples, which ImPACT ® measures 2 distinct factors: memory and speed. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Factor structure of the functional movement screen in marine officer candidates.

PubMed

Kazman, Josh B; Galecki, Jeffrey M; Lisman, Peter; Deuster, Patricia A; OʼConnor, Francis G

2014-03-01

Functional movement screening (FMS) is a musculoskeletal assessment that is intended to fill a gap between preparticipation examinations and performance tests. Functional movement screening consists of 7 standardized movements involving multiple muscle groups that are rated 0-3 during performance; scores are combined into a final score, which is intended to predict injury risk. This use of a sum-score in this manner assumes that the items are unidimensional and scores are internally consistent, which are measures of internal reliability. Despite research into the FMS' predictive value and interrater reliability, research has not assessed its psychometric properties. The present study is a standard psychometric analysis of the FMS and is the first to assess the internal consistency and factor structure of the FMS, using Cronbach's alpha and exploratory factor analysis (EFA). Using a cohort of 877 male and 57 female Marine officer candidates who performed the FMS, EFA of polychoric correlations with varimax rotation was conducted to explore the structure of the FMS. Tests were repeated on the original scores, which integrated feelings of pain during movement (0-3), and then on scores discounting the pain instruction and based only on the performance (1-3), to determine whether pain ratings affected the factor structure. The average FMS score was 16.7 ± 1.8. Cronbach's alpha was 0.39. Exploratory factor analysis availed 2 components accounting for 21 and 17% and consisting of separate individual movements (shoulder mobility and deep squat, respectively). Analysis on scores discounting pain showed similar results. The factor structures were not interpretable, and the low Cronbach's alpha suggests a lack of internal consistency in FMS sum scores. Results do not offer support for validity of the FMS sum score as a unidimensional construct. In the absence of additional psychometric research, caution is warranted when using the FMS sum score.

Leadership: validation of a self-report scale.

PubMed

Dussault, Marc; Frenette, Eric; Fernet, Claude

2013-04-01

The aim of this paper was to propose and test the factor structure of a new self-report questionnaire on leadership. A sample of 373 school principals in the Province of Quebec, Canada completed the initial 46-item version of the questionnaire. In order to obtain a questionnaire of minimal length, a four-step procedure was retained. First, items analysis was performed using Classical Test Theory. Second, Rasch analysis was used to identify non-fitting or overlapping items. Third, a confirmatory factor analysis (CFA) using structural equation modelling was performed on the 21 remaining items to verify the factor structure of the scale. Results show that the model with a single third-order dimension (leadership), two second-order dimensions (transactional and transformational leadership), and one first-order dimension (laissez-faire leadership) provides a good fit to the data. Finally, invariance of factor structure was assessed with a second sample of 222 vice-principals in the Province of Quebec, Canada. This model is in agreement with the theoretical model developed by Bass (1985), upon which the questionnaire is based.

An SEM Assessment of the Internal Structure and Predictive Validity of the Abbreviated Early Adolescent HOME Inventory.

PubMed

Green, Samuel B; Pennar, Amy L; Bradley, Robert H

2018-05-01

The Home Observation for Measurement of the Environment (HOME) Inventory is designed to assess the quality and quantity of support, stimulation, and structure provided to children in the home environment. HOME has been widely used for research and applied purposes. We focused on an abbreviated version of the Early Adolescent HOME (EA-HOME-A) that was administered to 15-year-old adolescents and their parents ( N = 958) as part of the NICHD (National Institute of Child Health and Human Development) Study of Early Child Care and Youth Development. Our study had two objectives. First, we hypothesized and tested a bifactor model that specified a general factor in support of the use of the HOME total score and group factors for subsets of items in support of the content domain scores. Second, we applied structural equation modeling to relate the EA-HOME-A factors to outcome factors assessing maladaptive behaviors, autonomy, self-control, and cognitive-academic performance. The results supported the construct validity of the EA-HOME-A with respect to its internal structure as well as its correlates.

Development and Validation of Videogame Addiction Scale for Children (VASC).

PubMed

Yılmaz, Eyüp; Griffiths, Mark D; Kan, Adnan

2017-01-01

The aim of the present study was to develop a valid and reliable Videogame Addiction Scale for Children (VASC). The data were derived from 780 children who completed the Videogame Addiction Scale (405 girls and 375 boys; 48.1% ranging in age from 9 to 12 years). The sample was randomly split into two different sub-samples (sample 1, n  = 400; sample 2, n  = 380). Sample 1 was used to perform exploratory factor analysis (EFA) to define the factorial structure of VASC. As a result of EFA, a four-factor structure comprising 21 items was obtained and explained 55% of the total variance (the four factors being "self-control," "reward/reinforcement," "problems," and "involvement"). The internal consistency reliability of VASC has found 0.89. Confirmatory factor analysis (CFA) was performed to confirm the factorial structure obtained by EFA in the remaining half of sample ( n  = 390). The obtained fit indices from the CFA confirmed the structure of the EFA. The 21-item VASC has good psychometric properties that can be used among Turkish schoolchildren populations.

The Four Faces of Competition: The Development of the Multidimensional Competitive Orientation Inventory

PubMed Central

Orosz, Gábor; Tóth-Király, István; Büki, Noémi; Ivaskevics, Krisztián; Bőthe, Beáta; Fülöp, Márta

2018-01-01

To date, no short scale exists with established factor structure that can assess individual differences in competition. The aim of the present study was to uncover and operationalize the facets of competitive orientations with theoretical underpinning and strong psychometric properties. A total of 2676 respondents were recruited for four studies. The items were constructed based on qualitative research in different cultural contexts. A combined method of exploratory structural equation modeling (ESEM) and confirmatory factor analysis (CFA) was employed. ESEM resulted in a four-factor structure of the competitive orientations and this structure was supported by a series of CFAs on different comprehensive samples. The Multidimensional Competitive Orientation Inventory (MCOI) included 12 items and four factors: hypercompetitive orientation, self-developmental competitive orientation, anxiety-driven competition avoidance, and lack of interest toward competition. Strong gender invariance was established. The four facets of competition have differentiated relationship patterns with adaptive and maladaptive personality and motivational constructs. The MCOI can assess the adaptive and maladaptive facets of competitive orientations with a short, reliable, valid and theoretically underlined multidimensional measure. PMID:29872415

Surface Irregularity Factor as a Parameter to Evaluate the Fatigue Damage State of CFRP

PubMed Central

Zuluaga-Ramírez, Pablo; Frövel, Malte; Belenguer, Tomás; Salazar, Félix

2015-01-01

This work presents an optical non-contact technique to evaluate the fatigue damage state of CFRP structures measuring the irregularity factor of the surface. This factor includes information about surface topology and can be measured easily on field, by techniques such as optical perfilometers. The surface irregularity factor has been correlated with stiffness degradation, which is a well-accepted parameter for the evaluation of the fatigue damage state of composite materials. Constant amplitude fatigue loads (CAL) and realistic variable amplitude loads (VAL), representative of real in- flight conditions, have been applied to “dog bone” shaped tensile specimens. It has been shown that the measurement of the surface irregularity parameters can be applied to evaluate the damage state of a structure, and that it is independent of the type of fatigue load that has caused the damage. As a result, this measurement technique is applicable for a wide range of inspections of composite material structures, from pressurized tanks with constant amplitude loads, to variable amplitude loaded aeronautical structures such as wings and empennages, up to automotive and other industrial applications. PMID:28793655

Phenomenology of future-oriented mind-wandering episodes

PubMed Central

Stawarczyk, David; Cassol, Helena; D'Argembeau, Arnaud

2013-01-01

Recent research suggests that prospective and non-prospective forms of mind-wandering possess distinct properties, yet little is known about what exactly differentiates between future-oriented and non-future-oriented mind-wandering episodes. In the present study, we used multilevel exploratory factor analyses (MEFA) to examine the factorial structure of various phenomenological dimensions of mind-wandering, and we then investigated whether future-oriented mind-wandering episodes differ from other classes of mind-wandering along the identified factors. We found that the phenomenological dimensions of mind-wandering are structured in four factors: representational format (inner speech vs. visual imagery), personal relevance, realism/concreteness, and structuration. Prospective mind-wandering differed from non-prospective mind-wandering along each of these factors. Specifically, future-oriented mind-wandering episodes involved inner speech to a greater extent, were more personally relevant, more realistic/concrete, and more often part of structured sequences of thoughts. These results show that future-oriented mind-wandering possesses a unique phenomenological signature and provide new insights into how this particular form of mind-wandering may adaptively contribute to autobiographical planning. PMID:23882236

Structural factors associated with an increased risk of HIV and sexually transmitted infection transmission among street-involved youth

PubMed Central

Marshall, Brandon DL; Kerr, Thomas; Shoveller, Jean A; Montaner, Julio SG; Wood, Evan

2009-01-01

Background The prevalence of HIV and sexually transmitted infections (STIs) among street-involved youth greatly exceed that of the general adolescent population; however, little is known regarding the structural factors that influence disease transmission risk among this population. Methods Between September 2005 and October 2006, 529 street-involved youth were enroled in a prospective cohort known as the At Risk Youth Study (ARYS). We examined structural factors associated with number of sex partners using quasi-Poisson regression and consistent condom use using logistic regression. Results At baseline, 415 (78.4%) were sexually active, of whom 253 (61.0%) reported multiple sex partners and 288 (69.4%) reported inconsistent condom use in the past six months. In multivariate analysis, self-reported barriers to health services were inversely associated with consistent condom use (adjusted odds ratio [aOR] = 0.52, 95%CI: 0.25 – 1.07). Structural factors that were associated with greater numbers of sex partners included homelessness (adjusted incidence rate ratio [aIRR] = 1.54, 95%CI: 1.11 – 2.14) and having an area restriction that affects access to services (aIRR = 2.32, 95%CI: 1.28 – 4.18). Being searched or detained by the police was significant for males (aIRR = 1.36, 95%CI: 1.02 – 1.81). Conclusion Although limited by its cross-sectional design, our study found several structural factors amenable to policy-level interventions independently associated with sexual risk behaviours. These findings imply that the criminalization and displacement of street-involved youth may increase the likelihood that youth will engage in sexual risk behaviours and exacerbate the negative impact of resultant health outcomes. Moreover, our findings indicate that environmental-structural interventions may help to reduce the burden of these diseases among street youth in urban settings. PMID:19134203

Relationship between oral health-related knowledge, attitudes and behavior among 15-16-year-old adolescents: a structural equation modeling approach.

PubMed

Tolvanen, Mimmi; Lahti, Satu; Miettunen, Jouko; Hausen, Hannu

2012-03-01

The aim of this study was to confirm the previously observed attitudinal factor structure related to behavioral change and the knowledge-attitude-behavior model on dental health and hygiene among adolescents. The study population consisted of all 8(th) and 9(th) graders (15-16 years) who started the 2004-2005 school year in Rauma, Finland (n = 827). Data on knowledge, attitudes, toothbrushing and using fluoride toothpaste were gathered by questionnaires. Hypothesized structure included four attitudinal factors related to dental health and hygiene: 'importance of toothbrushing when participating in social situations' (F1), 'importance of toothbrushing for health-related reasons and better appearance' (F2), 'being concerned about developing caries lesions' (F3) and 'importance of toothbrushing for feeling accepted' (F4). Structural equation modeling (SEM) was used to test the hypothesized model: pathways lead from knowledge to behavior both directly and via attitudes. The hypothesized model was also modified by removing non-significant pathways and studying the inter-relationships between attitudes. A confirmatory factor analysis revealed that factor F4 had to be removed. In the final model, knowledge influenced behavior directly and via two attitude factors, F1 and F2, which were inter-related. 'Concern about developing caries lesions' was a background factor influencing only knowledge. The final factor structure and SEM model were acceptable-to-good fit. Knowledge had a smaller effect on behavior than on attitudes. Our results support theories about the causal knowledge-attitudes-behavior chain, also for adolescents' oral health-related behaviors.

Factors affecting economies of scale in combined sewer systems.

PubMed

Maurer, Max; Wolfram, Martin; Anja, Herlyn

2010-01-01

A generic model is introduced that represents the combined sewer infrastructure of a settlement quantitatively. A catchment area module first calculates the length and size distribution of the required sewer pipes on the basis of rain patterns, housing densities and area size. These results are fed into the sewer-cost module in order to estimate the combined sewer costs of the entire catchment area. A detailed analysis of the relevant input parameters for Swiss settlements is used to identify the influence of size on costs. The simulation results confirm that an economy of scale exists for combined sewer systems. This is the result of two main opposing cost factors: (i) increased construction costs for larger sewer systems due to larger pipes and increased rain runoff in larger settlements, and (ii) lower costs due to higher population and building densities in larger towns. In Switzerland, the more or less organically grown settlement structures and limited land availability emphasise the second factor to show an apparent economy of scale. This modelling approach proved to be a powerful tool for understanding the underlying factors affecting the cost structure for water infrastructures.

Factors influencing accuracy of cortical thickness in the diagnosis of Alzheimer's disease.

PubMed

Belathur Suresh, Mahanand; Fischl, Bruce; Salat, David H

2018-04-01

There is great value to use of structural neuroimaging in the assessment of Alzheimer's disease (AD). However, to date, predictive value of structural imaging tend to range between 80% and 90% in accuracy and it is unclear why this is the case given that structural imaging should parallel the pathologic processes of AD. There is a possibility that clinical misdiagnosis relative to the gold standard pathologic diagnosis and/or additional brain pathologies are confounding factors contributing to reduced structural imaging classification accuracy. We examined potential factors contributing to misclassification of individuals with clinically diagnosed AD purely from cortical thickness measures. Correctly classified and incorrectly classified groups were compared across a range of demographic, biological, and neuropsychological data including cerebrospinal fluid biomarkers, amyloid imaging, white matter hyperintensity (WMH) volume, cognitive, and genetic factors. Individual subject analyses suggested that at least a portion of the control individuals misclassified as AD from structural imaging additionally harbor substantial AD biomarker pathology and risk, yet are relatively resistant to cognitive symptoms, likely due to "cognitive reserve," and therefore clinically unimpaired. In contrast, certain clinical control individuals misclassified as AD from cortical thickness had increased WMH volume relative to other controls in the sample, suggesting that vascular conditions may contribute to classification accuracy from cortical thickness measures. These results provide examples of factors that contribute to the accuracy of structural imaging in predicting a clinical diagnosis of AD, and provide important information about considerations for future work aimed at optimizing structural based diagnostic classifiers for AD. © 2017 Wiley Periodicals, Inc.

The structural basis for the functional comparability of Factor VIII and the long-acting variant recombinant Factor VIII Fc fusion protein

PubMed Central

Leksa, N.C.; Chiu, P.-L.; Bou-Assaf, G.M.; Quan, C.; Liu, Z.; Goodman, A.B.; Chambers, M.G.; Tsutakawa, S.E.; Hammel, M.; Peters, R.T.; Walz, T.; Kulman, J.D.

2017-01-01

SUMMARY Background Fusion of the human IgG1 Fc domain to the C-terminal C2 domain of B domain-deleted (BDD) factor VIII (FVIII) results in the rFVIIIFc fusion protein that has a 1.5-fold longer half-life in humans. Objective To assess the structural properties of rFVIIIFc by comparing its constituent FVIII and Fc elements with their respective isolated components and evaluating their structural independence within rFVIIIFc. Methods rFVIIIFc and its isolated FVIII and Fc components were compared by hydrogen-deuterium exchange mass spectrometry (HDX-MS). The structure of rFVIIIFc was also evaluated by X-ray crystallography, small-angle X-ray scattering (SAXS), and electron microscopy (EM). The degree of steric interference by the appended Fc domain was assessed by EM and surface plasmon resonance (SPR). Results HDX-MS analysis of rFVIIIFc revealed that fusion caused no structural perturbations in FVIII or Fc. The rFVIIIFc crystal structure showed that the FVIII component is indistinguishable from published BDD FVIII structures. The Fc domain was not observed, indicating high mobility. SAXS analysis was consistent with an ensemble of rigid-body models in which the Fc domain exists in a largely extended orientation relative to FVIII. Binding of Fab fragments of anti-C2 domain antibodies to BDD FVIII was visualized by EM, and the affinities of the corresponding intact antibodies for BDD FVIII and rFVIIIFc were comparable by SPR analysis. Conclusions The FVIII and Fc components of rFVIIIFc are structurally indistinguishable from their isolated constituents and exhibit a high degree of structural independence, consistent with the functional comparability of rFVIIIFc and unmodified FVIII. PMID:28397397

Structural validation of the Self-Compassion Scale with a German general population sample

PubMed Central

Kwakkenbos, Linda; Moran, Chelsea; Thombs, Brett; Albani, Cornelia; Bourkas, Sophia; Zenger, Markus; Brahler, Elmar; Körner, Annett

2018-01-01

Background Published validation studies have reported different factor structures for the Self-Compassion Scale (SCS). The objective of this study was to assess the factor structure of the SCS in a large general population sample representative of the German population. Methods A German population sample completed the SCS and other self-report measures. Confirmatory factor analysis (CFA) in MPlus was used to test six models previously found in factor analytic studies (unifactorial model, two-factor model, three-factor model, six-factor model, a hierarchical (second order) model with six first-order factors and two second-order factors, and a model with arbitrarily assigned items to six factors). In addition, three bifactor models were also tested: bifactor model #1 with two group factors (SCS positive items, called SCS positive) and SCS negative items, called SCS negative) and one general factor (overall SCS); bifactor model #2, which is a two-tier model with six group factors, three (SCS positive subscales) corresponding to one general dimension (SCS positive) and three (SCS negative subscales) corresponding to the second general dimension (SCS negative); bifactor model #3 with six group factors (six SCS subscales) and one general factor (overall SCS). Results The two-factor model, the six-factor model, and the hierarchical model showed less than ideal, but acceptable fit. The model fit indices for these models were comparable, with no apparent advantage of the six-factor model over the two-factor model. The one-factor model, the three-factor model, and bifactor model #3 showed poor fit. The other two bifactor models showed strong support for two factors: SCS positive and SCS negative. Conclusion The main results of this study are that, among the German general population, six SCS factors and two SCS factors fit the data reasonably well. While six factors can be modelled, the three negative factors and the three positive factors, respectively, did not reflect reliable or meaningful variance beyond the two summative positive and negative item factors. As such, we recommend the use of two subscale scores to capture a positive factor and a negative factor when administering the German SCS to general population samples and we strongly advise against the use of a total score across all SCS items. PMID:29408888

Quick screen of patients’ numeracy and document literacy skills: the factor structure of the Newest Vital Sign

PubMed Central

Huang, Yen-Ming; Shiyanbola, Olayinka O; Smith, Paul D; Chan, Hsun-Yu

2018-01-01

Introduction The Newest Vital Sign (NVS) is a survey designed to measure general health literacy whereby an interviewer asks six questions related to information printed on a nutritional label from an ice cream container. It enables researchers to evaluate several health literacy dimensions in a short period of time, including document literacy, comprehension, quantitative literacy (numeracy), application, and evaluation. No study has empirically examined which items belong to which latent dimensions of health literacy in the NVS using factor analysis. Identifying the factor structure of the NVS would enable health care providers to choose appropriate intervention strategies to address patients’ health literacy as well as improve their health outcomes accordingly. This study aimed to explore the factor structure of the NVS that is used to assess multiple dimensions of health literacy. Methods A cross-sectional study administering the NVS in a face-to-face manner was conducted at two family medicine clinics in the USA. One hundred and seventy four individuals who participated were at least 20 years old, diagnosed with type 2 diabetes, prescribed at least one oral diabetes medicine, and used English as their primary language. Exploratory factor analysis and confirmatory factor analysis were conducted to investigate the factor structure of the NVS. Results Numeracy and document literacy are two dimensions of health literacy that were identified and accounted for 63.05% of the variance in the NVS. Internal consistency (Cronbach’s alpha) of the NVS were 0.78 and 0.91 for numeracy and document literacy, respectively. Conclusion Numeracy and document literacy appropriately represent the factor structure of the NVS and may be used for assessing health literacy in greater detail for patients with type 2 diabetes. PMID:29844661

Factor Structure and Stability of Smoking-Related Health Beliefs in the National Lung Screening Trial

PubMed Central

Koblitz, Amber R.; Persoskie, Alexander; Ferrer, Rebecca A.; Klein, William M. P.; Dwyer, Laura A.; Park, Elyse R.

2016-01-01

Introduction: Absolute and comparative risk perceptions, worry, perceived severity, perceived benefits, and self-efficacy are important theoretical determinants of tobacco use, but no measures have been validated to ensure the discriminant validity as well as test-retest reliability of these measures in the tobacco context. The purpose of the current study is to examine the reliability and factor structure of a measure assessing smoking-related health cognitions and emotions in a national sample of current and former heavy smokers in the National Lung Screening Trial. Methods: A sub-study of the National Lung Screening Trial assessed current and former smokers’ (age 55–74; N = 4379) self-reported health cognitions and emotions at trial enrollment and at 12-month follow-up. Items were derived from the Health Belief Model and Self-Regulation Model. Results: An exploratory factor analysis of baseline responses revealed a five-factor structure for former smokers (risk perceptions, worry, perceived severity, perceived benefits, and self-efficacy) and a six-factor structure for current smokers, such that absolute risk and comparative risk perceptions emerged as separate factors. A confirmatory factor analysis of 12-month follow-up responses revealed a good fit for the five latent constructs for former smokers and six latent constructs for current smokers. Longitudinal stability of these constructs was also demonstrated. Conclusions: This is the first study to examine tobacco-related health cognition and emotional constructs over time in current and former heavy smokers undergoing lung screening. This study found that the theoretical constructs were stable across time and that the factor structure differed based on smoking status (current vs. former). PMID:25964503

Personal and Situational Factors Influencing Intrinsic Interest of Adolescent Girls in School Physical Education: A Structural Equation Modelling Analysis.

ERIC Educational Resources Information Center

Cury, Francois; Biddle, Stuart; Famose, Jean-Pierre; Goudas, Marios; Sarrazin, Philippe; Durand, Marc

1996-01-01

Presents the results of a study that assessed the influence of individual and contextual factors on adolescent girls' interest in school physical education. Suggests that classroom environment is more important than individual goals in influencing pupil interest. Results are discussed in the context of theoretical propositions of goal perspectives…

New Parenting Challenges in Europe Today.

ERIC Educational Resources Information Center

Fthenakis, Wassilios E.

This article discusses factors affecting parents in contemporary Europe. The focus is on family development, mechanisms conditioning social and family interactions, and the historical processes that are resulting in changes in family structure. Family changes discussed include the declining birthrate, structural conditions for parenthood, changing…

Intrinsic factors of Peltigera lichens influence the structure of the associated soil bacterial microbiota.

PubMed

Leiva, Diego; Clavero-León, Claudia; Carú, Margarita; Orlando, Julieta

2016-11-01

Definition of lichens has evolved from bi(tri)partite associations to multi-species symbioses, where bacteria would play essential roles. Besides, although soil bacterial communities are known to be affected by edaphic factors, when lichens grow upon them these could become less preponderant. We hypothesized that the structure of both the lichen microbiota and the microbiota in the soil underneath lichens is shaped by lichen intrinsic and extrinsic factors. In this work, intrinsic factors corresponded to mycobiont and cyanobiont identities of Peltigera lichens, metabolite diversity and phenoloxidase activity and extrinsic factors involved the site of the forest where lichens grow. Likewise, the genetic and metabolic structure of the lichen and soil bacterial communities were analyzed by fingerprinting. Among the results, metabolite diversity was inversely related to the genetic structure of bacterial communities of lichens and soils, highlighting the far-reaching effect of these substances; while phenoloxidase activity was inversely related to the metabolic structure only of the lichen bacterial microbiota, presuming a more limited effect of the products of these enzymes. Soil bacterial microbiota was different depending on the site and, strikingly, according to the cyanobiont present in the lichen over them, which could indicate an influence of the photobiont metabolism on the availability of soil nutrients. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Biomotor structures in elite female handball players according to performance.

PubMed

Cavala, Marijana; Rogulj, Nenad; Srhoj, Vatromir; Srhoj, Ljerka; Katić, Ratko

2008-03-01

In order to identify biomotor structures in elite female handball players, factor structures of morphological characteristics and basic motor abilities, and of variables evaluating situation motor abilities of elite female handball players (n = 53) were determined first, followed by determination of differences and relations of the morphological, motor and specific motor space according to handball performance. Factor analysis of 16 morphological measures produced three morphological factors, i.e. factor of absolute voluminosity, i.e. mesoendomorphy, factor of longitudinal skeleton dimensionality, and factor of transverse hand dimensionality. Factor analysis of 15 motor variables yielded five basic motor dimensions, i.e. factor of agility, factor of throwing explosive strength, factor of running explosive strength (sprint), factor of jumping explosive strength and factor of movement frequency rate. Factor analysis of 5 situation motor variables produced two dimensions: factor of specific agility with explosiveness and factor of specific precision with ball manipulation. Analysis of variance yielded greatest differences relative to handball performance in the factor of specific agility and throwing strength, and the factor of basic motoricity that integrates the ability of coordination (agility) with upper extremity throwing explosiveness and lower extremity sprint (30-m sprint) and jumping (standing triple jump). Considering morphological factors, the factor of voluminosity, i.e. mesoendomorphy, which is defined by muscle mass rather than adipose tissue, was found to contribute significantly to the players'performance. Results of regression analysis indicated the handball performance to be predominantly determined by the general specific motor factor based on specific agility and explosiveness, and by the morphological factor based on body mass and volume, i.e. muscle mass. Concerning basic motor abilities, the factor of movement frequency rate, which is associated with the ability of ball manipulation, was observed to predict significantly the handball players' performance.

Exploratory factor analysis of self-reported symptoms in a large, population-based military cohort

PubMed Central

2010-01-01

Background US military engagements have consistently raised concern over the array of health outcomes experienced by service members postdeployment. Exploratory factor analysis has been used in studies of 1991 Gulf War-related illnesses, and may increase understanding of symptoms and health outcomes associated with current military conflicts in Iraq and Afghanistan. The objective of this study was to use exploratory factor analysis to describe the correlations among numerous physical and psychological symptoms in terms of a smaller number of unobserved variables or factors. Methods The Millennium Cohort Study collects extensive self-reported health data from a large, population-based military cohort, providing a unique opportunity to investigate the interrelationships of numerous physical and psychological symptoms among US military personnel. This study used data from the Millennium Cohort Study, a large, population-based military cohort. Exploratory factor analysis was used to examine the covariance structure of symptoms reported by approximately 50,000 cohort members during 2004-2006. Analyses incorporated 89 symptoms, including responses to several validated instruments embedded in the questionnaire. Techniques accommodated the categorical and sometimes incomplete nature of the survey data. Results A 14-factor model accounted for 60 percent of the total variance in symptoms data and included factors related to several physical, psychological, and behavioral constructs. A notable finding was that many factors appeared to load in accordance with symptom co-location within the survey instrument, highlighting the difficulty in disassociating the effects of question content, location, and response format on factor structure. Conclusions This study demonstrates the potential strengths and weaknesses of exploratory factor analysis to heighten understanding of the complex associations among symptoms. Further research is needed to investigate the relationship between factor analytic results and survey structure, as well as to assess the relationship between factor scores and key exposure variables. PMID:20950474

Male Role Norms Inventory-Short Form (MRNI-SF): development, confirmatory factor analytic investigation of structure, and measurement invariance across gender.

PubMed

Levant, Ronald F; Hall, Rosalie J; Rankin, Thomas J

2013-04-01

The current study reports the development from the Male Role Norms Inventory-Revised (MRNI-R; Levant, Rankin, Williams, Hasan, & Smalley, 2010) of the 21-item MRNI-Short Form (MRNI-SF). Confirmatory factor analysis of MRNI-SF responses from a sample of 1,017 undergraduate participants (549 men, 468 women) indicated that the best fitting "bifactor" model incorporated the hypothesized 7-factor structure while explicitly modeling an additional, general traditional masculinity ideology factor. Specifically, each item-level indicator loaded on 2 factors: a general traditional masculinity ideology factor and a specific factor corresponding to 1 of the 7 hypothesized traditional masculinity ideology norms. The bifactor model was assessed for measurement invariance across gender groups, with findings of full configural invariance and partial metric invariance, such that factor loadings were equivalent across the gender groups for the 7 specific factors but not for the general traditional masculinity ideology factor. Theoretical explanations for this latter result include the potential that men's sense of self or identity may be engaged when responding to questions asking to what extent they agree or disagree with normative statements about their behavior, a possibility that could be investigated in future research by examining the associations of the general and specific factors with measures of masculine identity. Additional exploratory invariance analyses demonstrated latent mean differences between men and women on 4 of the 8 factors, and equivocal results for invariance of item intercepts, item uniquenesses, and factor variances-covariances.

Elasto-limited plastic analysis of structures for probabilistic conditions

NASA Astrophysics Data System (ADS)

Movahedi Rad, M.

2018-06-01

With applying plastic analysis and design methods, significant saving in material can be obtained. However, as a result of this benefit excessive plastic deformations and large residual displacements might develop, which in turn might lead to unserviceability and collapse of the structure. In this study, for deterministic problem the residual deformation of structures is limited by considering a constraint on the complementary strain energy of the residual forces. For probabilistic problem the constraint for the complementary strain energy of the residual forces is given randomly and critical stresses updated during the iteration. Limit curves are presented for the plastic limit load factors. The results show that these constraints have significant effects on the load factors. The formulations of the deterministic and probabilistic problems lead to mathematical programming which are solved by the use of nonlinear algorithm.

The structure of the Hospital Anxiety and Depression Scale in four cohorts of community-based, healthy older people: the HALCyon program.

PubMed

Gale, Catharine R; Allerhand, Michael; Sayer, Avan Aihie; Cooper, Cyrus; Dennison, Elaine M; Starr, John M; Ben-Shlomo, Yoav; Gallacher, John E; Kuh, Diana; Deary, Ian J

2010-06-01

The Hospital Anxiety and Depression Scale (HADS) is widely used but evaluation of its psychometric properties has produced equivocal results. Little is known about its structure in non-clinical samples of older people. We used data from four cohorts in the HALCyon collaborative research program into healthy aging: the Caerphilly Prospective Study, the Hertfordshire Ageing Study, the Hertfordshire Cohort Study, and the Lothian Birth Cohort 1921. We used exploratory factor analysis and confirmatory factor analysis with multi-group comparisons to establish the structure of the HADS and test for factorial invariance between samples. Exploratory factor analysis showed a bi-dimensional structure (anxiety and depression) of the scale in men and women in each cohort. We tested a hypothesized three-factor model but high correlations between two of the factors made a two-factor model more psychologically plausible. Multi-group confirmatory factor analysis revealed that the sizes of the respective item loadings on the two factors were effectively identical in men and women from the same cohort. There was more variation between cohorts, particularly those from different parts of the U.K. and in whom the HADS was administered differently. Differences in social-class distribution accounted for part of this variation. Scoring the HADS as two subscales of anxiety and depression is appropriate in non-clinical populations of older men and women. However, there were differences between cohorts in the way that individual items were linked with the constructs of anxiety and depression, perhaps due to differences in sociocultural factors and/or in the administration of the scale.

National Institutes of Health Toolbox Emotion Battery for English- and Spanish-speaking adults: normative data and factor-based summary scores.

PubMed

Babakhanyan, Ida; McKenna, Benjamin S; Casaletto, Kaitlin B; Nowinski, Cindy J; Heaton, Robert K

2018-01-01

The National Institutes of Health Toolbox Emotion Battery (NIHTB-EB) is a "common currency", computerized assessment developed to measure the full spectrum of emotional health. Though comprehensive, the NIHTB-EB's 17 scales may be unwieldy for users aiming to capture more global indices of emotional functioning. NIHTB-EB was administered to 1,036 English-speaking and 408 Spanish-speaking adults as a part of the NIH Toolbox norming project. We examined the factor structure of the NIHTB-EB in English- and Spanish-speaking adults and developed factor analysis-based summary scores. Census-weighted norms were presented for English speakers, and sample-weighted norms were presented for Spanish speakers. Exploratory factor analysis for both English- and Spanish-speaking cohorts resulted in the same 3-factor solution: 1) negative affect, 2) social satisfaction, and 3) psychological well-being. Confirmatory factor analysis supported similar factor structures for English- and Spanish-speaking cohorts. Model fit indices fell within the acceptable/good range, and our final solution was optimal compared to other solutions. Summary scores based upon the normative samples appear to be psychometrically supported and should be applied to clinical samples to further validate the factor structures and investigate rates of problematic emotions in medical and psychiatric populations.

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study.

PubMed

Rönnberg, Jerker; Lunner, Thomas; Ng, Elaine Hoi Ning; Lidestam, Björn; Zekveld, Adriana Agatha; Sörqvist, Patrik; Lyxell, Björn; Träff, Ulf; Yumba, Wycliffe; Classon, Elisabet; Hällgren, Mathias; Larsby, Birgitta; Signoret, Carine; Pichora-Fuller, M Kathleen; Rudner, Mary; Danielsson, Henrik; Stenfelt, Stefan

2016-11-01

The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R(2) = 0.40). All LEVEL 2 factors are important theoretically as well as for clinical assessment.

A structural equation modelling approach examining the pathways between safety climate, behaviour performance and workplace slipping

PubMed Central

Swedler, David I; Verma, Santosh K; Huang, Yueng-Hsiang; Lombardi, David A; Chang, Wen-Ruey; Brennan, Melayne; Courtney, Theodore K

2015-01-01

Objective Safety climate has previously been associated with increasing safe workplace behaviours and decreasing occupational injuries. This study seeks to understand the structural relationship between employees’ perceptions of safety climate, performing a safety behaviour (ie, wearing slip-resistant shoes) and risk of slipping in the setting of limited-service restaurants. Methods At baseline, we surveyed 349 employees at 30 restaurants for their perceptions of their safety training and management commitment to safety as well as demographic data. Safety performance was identified as wearing slip-resistant shoes, as measured by direct observation by the study team. We then prospectively collected participants’ hours worked and number of slips weekly for the next 12 weeks. Using a confirmatory factor analysis, we modelled safety climate as a higher order factor composed of previously identified training and management commitment factors. Results The 349 study participants experienced 1075 slips during the 12-week follow-up. Confirmatory factor analysis supported modelling safety climate as a higher order factor composed of safety training and management commitment. In a structural equation model, safety climate indirectly affected prospective risk of slipping through safety performance, but no direct relationship between safety climate and slips was evident. Conclusions Results suggest that safety climate can reduce workplace slips through performance of a safety behaviour as well as suggesting a potential causal mechanism through which safety climate can reduce workplace injuries. Safety climate can be modelled as a higher order factor composed of safety training and management commitment. PMID:25710968

Structural validity and reliability of the Spanish version of the White Bear Suppression Inventory (WBSI) in a sample of the general Spanish population.

PubMed

González Rodríguez, Manuel; Avero Delgado, Pedro; Rovella, Anna Teresa; Cubas León, Rosario

2008-11-01

This paper introduces the validation of the Spanish adaptation of the White Bear Suppression Inventory (WBSI) by Wegner and Zanakos (1994). A sample of 833 people from the general population completed the WBSI along with other questionnaires. The exploratory factor analysis and the confirmatory factor analysis supported a two-factor solution accounting for 51.8% of the cumulative variance. This structure is comprised of the two following factors: unwanted intrusive thoughts (alpha = .87, r = .70) and actions of distraction and suppression of thoughts (alpha = .80, r = .60). Both internal consistency reliability (alpha = .89) and test-retest reliability (r = .71) showed adequate homogeneity, sound consistency, and stability over time. The results are discussed bearing in mind both isolated factors and the possible relationships of the suppression factor with automatic negative thoughts and insomnia.

'Post-deployment appraisal' and the relationship with stress and psychological health in Australian veterans.

PubMed

Wright, Breanna; Forbes, Andrew; Kelsall, Helen; Clarke, David; Ikin, Jill; Sim, Malcolm

2015-12-01

Understanding how veterans appraise their post-deployment experiences could provide insight into better assisting their deployment transitions. We aimed to assess the factor structure of positive and negative post-deployment appraisals in Australian veterans and to examine the resultant factors in their relationship with military stress and psychological health. Questions capturing post-deployment attitudes were developed by the researchers in collaboration with veterans. The questions were administered to 1938 veterans and the results factor analysed. The relationships between post-deployment appraisal, military stress and psychological health were examined using Structural Equation Modelling. A three-factor solution was found for the post-deployment appraisal questions; representing personal development, lack of recognition, and appreciation of life and country. Military stress was associated with the three factors and psychological health. The three factors were weakly to moderately associated with psychological health. Mediation between military stress and psychological health by any post-deployment appraisal factor was minimal. Post-deployment appraisal measures three important attitudes and concerns of veterans after deployment. Military stress is associated with the post-deployment appraisal factors. However, the factors did not mediate the relationship between military stress and psychological health. These factors provide insight into how veterans appraise their complex array of post-deployment experiences, and may provide useful in regard to transitions and integration into civilian life.

The role of burnout syndrome as a mediator for the effect of psychosocial risk factors on the intensity of musculoskeletal disorders: a structural equation modeling approach.

PubMed

Gholami, Tahereh; Pahlavian, Ahmad Heidari; Akbarzadeh, Mahdi; Motamedzade, Majid; Moghaddam, Rashid Heidari

2016-01-01

This study examined the hypothesis that burnout syndrome mediates effects of psychosocial risk factors and intensity of musculoskeletal disorders (MSDs) among hospital nurses. The sample was composed of 415 nurses from various wards across five hospitals of Iran's Hamedan University of Medical Sciences. Data were collected through three questionnaires: job content questionnaire, Maslach burnout inventory and visual analogue scale. Results of structural equation modeling with a mediating effect showed that psychosocial risk factors were significantly related to changes in burnout, which in turn affects intensity of MSDs.

Assessing a Norwegian translation of the Organizational Climate Measure.

PubMed

Bernstrøm, Vilde Hoff; Lone, Jon Anders; Bjørkli, Cato A; Ulleberg, Pål; Hoff, Thomas

2013-04-01

This study investigated the Norwegian translation of the Organizational Climate Measure developed by Patterson and colleagues. The Organizational Climate Measure is a global measure of organizational climate based on Quinn and Rohrbaugh's competing values model. The survey was administered to a Norwegian branch of an international service sector company (N = 555). The results revealed satisfactory internal reliability and interrater agreement for the 17 scales, and confirmatory factor analysis supported the original factor structure. The findings gave preliminary support for the Organizational Climate Measure as a reliable measure with a stable factor structure, and indicated that it is potentially useful in the Norwegian context.

Validity of a brief workaholism scale.

PubMed

Del Líbano, Mario; Llorens, Susana; Salanova, Marisa; Schaufeli, Wilmar

2010-02-01

The current study contributes to our understanding of workaholism as a negative construct, and to its measurement by examining the psychometric properties of a short 10-item workaholism scale called DUWAS (Dutch Work Addiction Scale). Confirmatory factor analyses were carried out in a heterogeneous sample of 2,714 employees from the Netherlands (n= 2,164) and Spain (n= 550). The results confirmed the expected two-factor structure of workaholism: working excessively and working compulsively. Moreover, multi-group analyses showed that this two-factor structure was invariant across both countries. Lastly, negative correlations among workaholism and psychosocial well-being (i.e., perceived health and happiness) are indicators of the negative nature of workaholism.

Structural validity of the Wechsler Intelligence Scale for Children-Fifth Edition: Confirmatory factor analyses with the 16 primary and secondary subtests.

PubMed

Canivez, Gary L; Watkins, Marley W; Dombrowski, Stefan C

2017-04-01

The factor structure of the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V; Wechsler, 2014a) standardization sample (N = 2,200) was examined using confirmatory factor analyses (CFA) with maximum likelihood estimation for all reported models from the WISC-V Technical and Interpretation Manual (Wechsler, 2014b). Additionally, alternative bifactor models were examined and variance estimates and model-based reliability estimates (ω coefficients) were provided. Results from analyses of the 16 primary and secondary WISC-V subtests found that all higher-order CFA models with 5 group factors (VC, VS, FR, WM, and PS) produced model specification errors where the Fluid Reasoning factor produced negative variance and were thus judged inadequate. Of the 16 models tested, the bifactor model containing 4 group factors (VC, PR, WM, and PS) produced the best fit. Results from analyses of the 10 primary WISC-V subtests also found the bifactor model with 4 group factors (VC, PR, WM, and PS) produced the best fit. Variance estimates from both 16 and 10 subtest based bifactor models found dominance of general intelligence (g) in accounting for subtest variance (except for PS subtests) and large ω-hierarchical coefficients supporting general intelligence interpretation. The small portions of variance uniquely captured by the 4 group factors and low ω-hierarchical subscale coefficients likely render the group factors of questionable interpretive value independent of g (except perhaps for PS). Present CFA results confirm the EFA results reported by Canivez, Watkins, and Dombrowski (2015); Dombrowski, Canivez, Watkins, and Beaujean (2015); and Canivez, Dombrowski, and Watkins (2015). (PsycINFO Database Record (c) 2017 APA, all rights reserved).

[Appearance of psychopathic tendencies among children and adolescents].

PubMed

Pataky, Nóra; Körmendi, Attila

2010-01-01

There has been a growing body of researches about psychopathic tendencies appearing among children and adolescents. First generation studies differentiated psychopathic constellation from conduct problems in childhood and pointed out that the presence of these traits predict unpleasant therapeutic prognosis and is partly independent from quality of parenting. The factor structure of constellation is similar to the factor structure of adult psychopaths. Surveying the structure became clear that C/U traits are the core of the child and adolescent psychopathic constellation. This paper summarize results of empirical studies connected to C/U traits among children and adolescents. We introduce debatable questions about child and adolescent psychopathic traits and connected empirical studies.

Bem Sex Role Inventory Validation in the International Mobility in Aging Study.

PubMed

Ahmed, Tamer; Vafaei, Afshin; Belanger, Emmanuelle; Phillips, Susan P; Zunzunegui, Maria-Victoria

2016-09-01

This study investigated the measurement structure of the Bem Sex Role Inventory (BSRI) with different factor analysis methods. Most previous studies on validity applied exploratory factor analysis (EFA) to examine the BSRI. We aimed to assess the psychometric properties and construct validity of the 12-item short-form BSRI in a sample administered to 1,995 older adults from wave 1 of the International Mobility in Aging Study (IMIAS). We used Cronbach's alpha to assess internal consistency reliability and confirmatory factor analysis (CFA) to assess psychometric properties. EFA revealed a three-factor model, further confirmed by CFA and compared with the original two-factor structure model. Results revealed that a two-factor solution (instrumentality-expressiveness) has satisfactory construct validity and superior fit to data compared to the three-factor solution. The two-factor solution confirms expected gender differences in older adults. The 12-item BSRI provides a brief, psychometrically sound, and reliable instrument in international samples of older adults.

Is Small Still Beautiful for the Strengths and Difficulties Questionnaire? Novel Findings Using Exploratory Structural Equation Modeling.

PubMed

Garrido, Luis Eduardo; Barrada, Juan Ramón; Aguasvivas, José Armando; Martínez-Molina, Agustín; Arias, Víctor B; Golino, Hudson F; Legaz, Eva; Ferrís, Gloria; Rojo-Moreno, Luis

2018-06-01

During the present decade a large body of research has employed confirmatory factor analysis (CFA) to evaluate the factor structure of the Strengths and Difficulties Questionnaire (SDQ) across multiple languages and cultures. However, because CFA can produce strongly biased estimations when the population cross-loadings differ meaningfully from zero, it may not be the most appropriate framework to model the SDQ responses. With this in mind, the current study sought to assess the factorial structure of the SDQ using the more flexible exploratory structural equation modeling approach. Using a large-scale Spanish sample composed of 67,253 youths aged between 10 and 18 years ( M = 14.16, SD = 1.07), the results showed that CFA provided a severely biased and overly optimistic assessment of the underlying structure of the SDQ. In contrast, exploratory structural equation modeling revealed a generally weak factorial structure, including questionable indicators with large cross-loadings, multiple error correlations, and significant wording variance. A subsequent Monte Carlo study showed that sample sizes greater than 4,000 would be needed to adequately recover the SDQ loading structure. The findings from this study prevent recommending the SDQ as a screening tool and suggest caution when interpreting previous results in the literature based on CFA modeling.

Numerical examination of like-honeycomb structures

NASA Astrophysics Data System (ADS)

John, Małgorzata; John, Antoni; Skarka, Wojciech

2018-01-01

In the paper based on the analogy with the biological tissue of bones, it was decided to examine more homogenous structure and also a heterogeneous structure too. Here, a new approach is proposed based on results from literature obtained using topology optimization 2D and 3D structures like beam, girder and cantilever. Proposed model of structure is similar to spatial trusses with honeycomb-shape porous. Parameters varied not only uniformly throughout the volume of the sample, but also be modified depending on various factors. They underwent a change in cell dimensions, among other things, the thickness of the wall. The obtained results were compared with those obtained previously for homogeneous samples.

Latent structure of the Wisconsin Card Sorting Test: a confirmatory factor analytic study.

PubMed

Greve, Kevin W; Stickle, Timothy R; Love, Jeffrey M; Bianchini, Kevin J; Stanford, Matthew S

2005-05-01

The present study represents the first large scale confirmatory factor analysis of the Wisconsin Card Sorting Test (WCST). The results generally support the three factor solutions reported in the exploratory factor analysis literature. However, only the first factor, which reflects general executive functioning, is statistically sound. The secondary factors, while likely reflecting meaningful cognitive abilities, are less stable except when all subjects complete all 128 cards. It is likely that having two discontinuation rules for the WCST has contributed to the varied factor analytic solutions reported in the literature and early discontinuation may result in some loss of useful information. Continued multivariate research will be necessary to better clarify the processes underlying WCST performance and their relationships to one another.

Relations between anger and DSM-5 posttraumatic stress disorder symptoms.

PubMed

Durham, Tory A; Byllesby, Brianna M; Armour, Cherie; Forbes, David; Elhai, Jon D

2016-10-30

The present study investigated the relationship between posttraumatic stress disorder (PTSD) and anger. Anger co-occurring with PTSD is found to have a severe effect across a wide range of traumatic experiences, making this an important relationship to examine. The present study utilized data regarding dimensions of PTSD symptoms and anger collected from a non-clinical sample of 247 trauma-exposed participants. Confirmatory factor analysis (CFA) was used to determine the underlying factor structure of both PTSD and anger by examining anger in the context of three models of PTSD. Results indicate that a five-factor representation of PTSD and one-factor representation of anger fit the data best. Additionally, anger demonstrated a strong relationship with the dysphoric arousal and negative alterations in cognitions and mood (NACM) factors; and dysphoric arousal was differentially related to anger. Clinical implications include potential need to reevaluate PTSD's diagnostic symptom structure and highlight the potential need to target and treat comorbid anger in individuals with PTSD. In regard to research, these results support the heterogeneity of PTSD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Electromagnetic Transition Form Factor of the η meson with WASA-at-COSY

NASA Astrophysics Data System (ADS)

Goswami, A.

2016-11-01

In this work we present a study of the Dalitz decay η → γe+e-. The aim of this work is to measure the transition form factor of the η meson. The transition form factor of the η meson describes the electromagnetic structure of the meson. The study of the Dalitz decay helps to calculate the transition form factor of the η meson. When a particle is point-like it's decay rate can be calculated within QED. However, the complex structure of the meson modifies its decay rate. The transition form factor is determined by comparing the lepton-antilepton invariant mass distribution with QED. For this study data on proton-proton reaction at a beam energy of 1.4 GeV has been collected with WASA-at-COSY detector at Forschungszentrum Juelich, Germany. In the higher invariant mass region recent theoretical calculations slightly deviate from the fit to the data. We expect better results in the higher invariant mass region than previous measurements. The preliminary results of the analysis will be presented.

Refining the Measurement of Distress Intolerance

PubMed Central

McHugh, R. Kathryn; Otto, Michael W.

2012-01-01

Distress intolerance is an important transdiagnostic variable that has long been implicated in the development and maintenance of psychological disorders. Self-report measurement strategies for distress intolerance have emerged from several different models of psychopathology and these measures have been applied inconsistently in the literature in the absence of a clear gold standard. The absence of a consistent assessment strategy has limited the ability to compare across studies and samples, thus hampering the advancement of this research agenda. This study evaluated the latent factor structure of existing measures of DI to examine the degree to which they are capturing the same construct. Results of confirmatory factor analysis in 3 samples totaling 400 participants provided support for a single factor latent structure. Individual items of these four scales were then correlated with this factor to identify those that best capture the core construct. Results provided consistent supported for 10 items that demonstrated the strongest concordance with this factor. The use of these 10 items as a unifying measure in the study of DI and future directions for the evaluation of its utility are discussed. PMID:22697451

Global search in photoelectron diffraction structure determination using genetic algorithms

NASA Astrophysics Data System (ADS)

Viana, M. L.; Díez Muiño, R.; Soares, E. A.; Van Hove, M. A.; de Carvalho, V. E.

2007-11-01

Photoelectron diffraction (PED) is an experimental technique widely used to perform structural determinations of solid surfaces. Similarly to low-energy electron diffraction (LEED), structural determination by PED requires a fitting procedure between the experimental intensities and theoretical results obtained through simulations. Multiple scattering has been shown to be an effective approach for making such simulations. The quality of the fit can be quantified through the so-called R-factor. Therefore, the fitting procedure is, indeed, an R-factor minimization problem. However, the topography of the R-factor as a function of the structural and non-structural surface parameters to be determined is complex, and the task of finding the global minimum becomes tough, particularly for complex structures in which many parameters have to be adjusted. In this work we investigate the applicability of the genetic algorithm (GA) global optimization method to this problem. The GA is based on the evolution of species, and makes use of concepts such as crossover, elitism and mutation to perform the search. We show results of its application in the structural determination of three different systems: the Cu(111) surface through the use of energy-scanned experimental curves; the Ag(110)-c(2 × 2)-Sb system, in which a theory-theory fit was performed; and the Ag(111) surface for which angle-scanned experimental curves were used. We conclude that the GA is a highly efficient method to search for global minima in the optimization of the parameters that best fit the experimental photoelectron diffraction intensities to the theoretical ones.

Past climate change drives current genetic structure of an endangered freshwater mussel species.

PubMed

Inoue, Kentaro; Lang, Brian K; Berg, David J

2015-04-01

Historical-to-recent climate change and anthropogenic disturbance affect species distributions and genetic structure. The Rio Grande watershed of the United States and Mexico encompasses ecosystems that are intensively exploited, resulting in substantial degradation of aquatic habitats. While significant anthropogenic disturbances in the Rio Grande are recent, inhospitable conditions for freshwater organisms likely existed prior to such disturbances. A combination of anthropogenic and past climate factors may contribute to current distributions of aquatic fauna in the Rio Grande basin. We used mitochondrial DNA and 18 microsatellite loci to infer evolutionary history and genetic structure of an endangered freshwater mussel, Popenaias popeii, throughout the Rio Grande drainage. We estimated spatial connectivity and gene flow across extant populations of P. popeii and used ecological niche models (ENMs) and approximate Bayesian computation (ABC) to infer its evolutionary history during the Pleistocene. structure results recovered regional and local population clusters in the Rio Grande. ENMs predicted drastic reductions in suitable habitat during the last glacial maximum. ABC analyses suggested that regional population structure likely arose in this species during the mid-to-late Pleistocene and was followed by a late Pleistocene population bottleneck in New Mexico populations. The local population structure arose relatively recently, perhaps due to anthropogenic factors. Popenaias popeii, one of the few freshwater mussel species native to the Rio Grande basin, is a case study for understanding how both geological and anthropogenic factors shape current population genetic structure. Conservation strategies for this species should account for the fragmented nature of contemporary populations. © 2015 John Wiley & Sons Ltd.

Ab initio study of the structure and dynamics of bulk liquid Fe

NASA Astrophysics Data System (ADS)

Marqués, M.; González, L. E.; González, D. J.

2015-10-01

Several static and dynamic properties of bulk liquid Fe at a thermodynamic state near its triple point have been evaluated by ab initio molecular dynamics simulations. The calculated static structure shows very good agreement with the available experimental data, including an asymmetric second peak in the structure factor which underlines a substantial local icosahedral short-range order in the liquid. The dynamical structure reveals propagating density fluctuations, with an associated dispersion relation which closely follows the experimental data. The dynamic structure factors S (q ,ω ) show a good agreement with their experimental counterparts which have been recently measured by an inelastic x-ray scattering experiment. The dynamical processes behind the S (q ,ω ) have been analyzed by using a model with two decay channels (a fast and a slow) associated with the relaxations of the collective excitations. The recent finding of transverselike excitation modes in the IXS data is analyzed by using the present ab initio simulation results. Several transport coefficients have been evaluated and the results are compared with the available experimental data.

Mapping the MMPI-2-RF Specific Problems Scales Onto Extant Psychopathology Structures.

PubMed

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.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borodin, Oleg; Price, David L.; Aoun, Bachir

The influence of water on the structure of a prototype ionic liquid (IL) 1-octyl-3-methyimidazolium tetrafluoroborate (C8mimBF4) is examined in the IL-rich regime using high-energy x-ray diffraction (HEXRD) and molecular dynamics (MD) simulations. A many-body polarizable force field APPLE&P was developed for C8mimBF4 water mixture. It predicts structure factors of pure IL and IL-water mixture in excellent agreement with the HEXRD experiments. The MD results provide detailed insights into the structural changes from the partial structure factors, 2-D projections of the simulation box and 3-D distribution functions. Water partitioning with IL and its competition with BF4- for complexing the imidazolium ringsmore » was examined. The added water molecules occupy a diffuse coordination shell around the imidazolium ring but are not present around the alkyl tail. The strong coordination of the fluorine atoms of the BF4- anions to the imidazolium ring is not significantly changed by the addition of water. These results are consistent with the very small differences in the average structure between the pure IL and the mixture.« less

The role of social and ecological processes in structuring animal populations: a case study from automated tracking of wild birds

PubMed Central

Farine, Damien R.; Firth, Josh A.; Aplin, Lucy M.; Crates, Ross A.; Culina, Antica; Garroway, Colin J.; Hinde, Camilla A.; Kidd, Lindall R.; Milligan, Nicole D.; Psorakis, Ioannis; Radersma, Reinder; Verhelst, Brecht; Voelkl, Bernhard; Sheldon, Ben C.

2015-01-01

Both social and ecological factors influence population process and structure, with resultant consequences for phenotypic selection on individuals. Understanding the scale and relative contribution of these two factors is thus a central aim in evolutionary ecology. In this study, we develop a framework using null models to identify the social and spatial patterns that contribute to phenotypic structure in a wild population of songbirds. We used automated technologies to track 1053 individuals that formed 73 737 groups from which we inferred a social network. Our framework identified that both social and spatial drivers contributed to assortment in the network. In particular, groups had a more even sex ratio than expected and exhibited a consistent age structure that suggested local association preferences, such as preferential attachment or avoidance. By contrast, recent immigrants were spatially partitioned from locally born individuals, suggesting differential dispersal strategies by phenotype. Our results highlight how different scales of social decision-making, ranging from post-natal dispersal settlement to fission–fusion dynamics, can interact to drive phenotypic structure in animal populations. PMID:26064644

Factor structure and psychometric properties of the Body Appreciation Scale-2 among adolescents and young adults in Danish, Portuguese, and Swedish.

PubMed

Lemoine, J E; Konradsen, H; Lunde Jensen, A; Roland-Lévy, C; Ny, P; Khalaf, A; Torres, S

2018-05-14

In recent years, the study of body image shifted from focusing on the negative aspects to a more extensive view of body image. The present study seeks to validate a measure of positive body image, the Body Appreciation Scale-2 (BAS-2; Tylka & Wood-Barcalow, 2015a) in Denmark, Portugal, and Sweden. Participants (N = 1012) were adolescents and young adults aged from 12 to 19. Confirmatory factor analyses confirmed the one-dimensional factor structure of the scale. Multi-group confirmatory factor analyses indicated that the scale was invariant across sex and country. Further results showed that BAS-2 was positively correlated with self-esteem, psychological well-being, and intuitive eating. It was negatively correlated with BMI among boys and girls in Portugal but not in Denmark and Sweden. Additionally, boys had higher body appreciation than girls. Results indicated that the BAS-2 has good psychometric properties in the three languages. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Spanish adaptation of the Stress Manifestations Scale of the Student Stress Inventory (SSI-SM)].

PubMed

Escobar Espejo, Milagros; Blanca, María J; Fernández-Baena, F Javier; Trianes Torres, María Victoria

2011-08-01

The aim of the present study was to translate into Spanish and to describe the psychometric properties of the Stress Manifestations Scale of the Student Stress Inventory (SSI-SM), developed by Fimian, Fastenau, Tashner and Cross to identify the main manifestations of stress in adolescents. The scale was applied to a sample of 1,002 pupils from years one and two of Secondary Education. The paper reports the factor structure, an item analysis, the internal consistency, differences by sex and academic year, external evidence of validity, and norms for scoring the scale. The results reveal a factor structure based on three first-order factors (emotional manifestations, physiological manifestations and behavioural manifestations) and one second-order factor (indicative of stress manifestations). In terms of external validity, there was a positive association with measures of perceived stress, aggressiveness, internalized/externalized symptoms, and a negative association with life satisfaction. The results show that the scale is an adequate tool for evaluating stress manifestations in adolescents.

Cross-ethnic generalizability of the three-factor model of psychopathy: the Youth Psychopathic Traits Inventory in an incarcerated sample of native Dutch and Moroccan immigrant boys.

PubMed

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

2011-01-01

Previous research provides support for the existence of the psychopathy construct in youths. However, studies regarding the psychometric properties of psychopathy measures with ethnic minority youths are lacking. In the present study, the three-factor structure of the Youth Psychopathic Traits Inventory (YPI) was examined for both native Dutch youth (N=158) and an ethnic minority group, Moroccans (N=141), in an incarcerated adolescent population in the Netherlands. Our results showed that the three-factor structure of the YPI is comparable across an ethnic majority and an ethnic minority group in an incarcerated sample in the Netherlands. Moreover, associations between psychopathic traits and mental health problems were similar for both ethnic groups. The results support the cross-ethnic generalizability of the three-factor model of psychopathy as measured through the Youth Psychopathic Traits Inventory. Copyright © 2011 Elsevier Ltd. All rights reserved.

The effects of rigid motions on elastic network model force constants

PubMed Central

Lezon, Timothy R.

2012-01-01

Elastic network models provide an efficient way to quickly calculate protein global dynamics from experimentally determined structures. The model’s single parameter, its force constant, determines the physical extent of equilibrium fluctuations. The values of force constants can be calculated by fitting to experimental data, but the results depend on the type of experimental data used. Here we investigate the differences between calculated values of force constants _t to data from NMR and X-ray structures. We find that X-ray B factors carry the signature of rigid-body motions, to the extent that B factors can be almost entirely accounted for by rigid motions alone. When fitting to more refined anisotropic temperature factors, the contributions of rigid motions are significantly reduced, indicating that the large contribution of rigid motions to B factors is a result of over-fitting. No correlation is found between force constants fit to NMR data and those fit to X-ray data, possibly due to the inability of NMR data to accurately capture protein dynamics. PMID:22228562

Generalized Structured Component Analysis

ERIC Educational Resources Information Center

Hwang, Heungsun; Takane, Yoshio

2004-01-01

We propose an alternative method to partial least squares for path analysis with components, called generalized structured component analysis. The proposed method replaces factors by exact linear combinations of observed variables. It employs a well-defined least squares criterion to estimate model parameters. As a result, the proposed method…

Correlation of soil microbes and soil micro-environment under long-term safflower (Carthamus tinctorius L.) plantation in China.

PubMed

Lu, Shuang; Quan, Wang; Wang, Shao-Ming; Liu, Hong-Ling; Tan, Yong; Zeng, Guang-Ping; Zhang, Xia

2013-04-01

Microbial community structure and ecological functions are influenced by interactions between above and belowground biota. There is an urgent need for intensive monitoring of microbes feedback of soil micro-ecosystem for setting up a good agricultural practice. Recent researches have revealed that many soils characteristic can effect microbial community structure. In the present study factors affecting microbial community structure and soil in Carthamus tinctorius plantations in arid agricultural ecosystem of northern Xinjiang, China were identified. The result of the study revealed that soil type was the key factor in safflower yield; Unscientific field management resulted high fertility level (bacteria dominant) of soil to turn to low fertility level (fungi dominant), and Detruded Canonical Correspondence Analysis (DCCA) showed that soil water content, organic matter, available N, P and K were the dominant factors affecting distribution of microbial community. Soil water content showed a significant positive correlation with soil microbes quantity (P < 0.01), while others showed a significant quantity correlation with soil microbe quantity (P < 0.05).

Ab-initio molecular dynamics simulations of liquid Hg-Pb alloys

NASA Astrophysics Data System (ADS)

Sharma, Nalini; Thakur, Anil; Ahluwalia, P. K.

2014-04-01

Ab-initio molecular dynamics simulations are performed to study the structural properties of liquid Hg-Pb alloys. The interatomic interactions are described by ab-initio pseudopotentials given by Troullier and Martins. Three liquid Hg-Pb mixtures (Hg30Pb70, Hg50Pb50 and Hg90Pb10) at 600K are considered. The radial distribution function g(r) and structure factor S(q) of considered alloys are compared with respective experimental results for liquid Hg (l-Hg) and lead (l-Pb). The radial distribution function g(r) shows the presence of short range order in the systems considered. Smooth curves of Bhatia-Thornton partial structure factors factor shows the presence of liquid state in the considered three alloys. Among the all considered alloys, Hg50Pb50 alloy shows presence of more chemical ordering and presence of hetero-coordination.

[Identification of the cumulative eco-environment effect of coal-electricity integration based on interpretative structural model].

PubMed

Han, Lin Wei; Fu, Xiao; Yan, Yan; Wang, Chen Xing; Wu, Gang

2017-05-18

In order to determine the cumulative eco-environmental effect of coal-electricity integration, we selected 29 eco-environmental factors including different development and construction activities of coal-electricity integration, soil, water, atmospheric conditions, biology, landscape, and ecology. Literature survey, expert questionnaire and interview were conducted to analyze the interactive relationships between different factors. The structure and correlations between the eco-environmental factors influenced by coal-electricity integration activities were analyzed using interpretive structural modeling (ISM) and the cumulative eco-environment effect of development and construction activities was determined. A research and evaluation framework for the cumulative eco-environmental effect was introduced in addition to specific evaluation and management needs. The results of this study would provide a theoretical and technical basis for planning and management of coal-electricity integration development activities.

Factor structure and sex differences on the Wechsler Preschool and Primary Scale of Intelligence in China, Japan and United States.

PubMed

Liu, Jianghong; Lynn, Richard

2011-08-01

This study presents data on the factor structure of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) and sex and cultural differences in WPPSI test scores among 5- and 6-year-olds from China, Japan, and the United States. Results show the presence of a verbal and nonverbal factor structure across all three countries. Sex differences on the 10 subtests were generally consistent, with a male advantage on a subtest of spatial abilities (Mazes). Males in the Chinese sample obtained significantly higher Full Scale IQ scores than females and had lower variability in their test scores. These observations were not present in the Japan and United States samples. Mean Full Scale IQ score in the Chinese sample was 104.1, representing a 4-point increase from 1988 to 2004.

Using structured additive regression models to estimate risk factors of malaria: analysis of 2010 Malawi malaria indicator survey data.

PubMed

Chirombo, James; Lowe, Rachel; Kazembe, Lawrence

2014-01-01

After years of implementing Roll Back Malaria (RBM) interventions, the changing landscape of malaria in terms of risk factors and spatial pattern has not been fully investigated. This paper uses the 2010 malaria indicator survey data to investigate if known malaria risk factors remain relevant after many years of interventions. We adopted a structured additive logistic regression model that allowed for spatial correlation, to more realistically estimate malaria risk factors. Our model included child and household level covariates, as well as climatic and environmental factors. Continuous variables were modelled by assuming second order random walk priors, while spatial correlation was specified as a Markov random field prior, with fixed effects assigned diffuse priors. Inference was fully Bayesian resulting in an under five malaria risk map for Malawi. Malaria risk increased with increasing age of the child. With respect to socio-economic factors, the greater the household wealth, the lower the malaria prevalence. A general decline in malaria risk was observed as altitude increased. Minimum temperatures and average total rainfall in the three months preceding the survey did not show a strong association with disease risk. The structured additive regression model offered a flexible extension to standard regression models by enabling simultaneous modelling of possible nonlinear effects of continuous covariates, spatial correlation and heterogeneity, while estimating usual fixed effects of categorical and continuous observed variables. Our results confirmed that malaria epidemiology is a complex interaction of biotic and abiotic factors, both at the individual, household and community level and that risk factors are still relevant many years after extensive implementation of RBM activities.

The implementation leadership scale (ILS): development of a brief measure of unit level implementation leadership

PubMed Central

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

The factor structure of the Spanish version of the Work-Family Culture Scale in a sample of workers from the advertising sector.

PubMed

Beléndez Vázquez, Marina; Martín Llaguno, Marta; Hernández Ruiz, Alejandra

2013-01-01

The Work-Family Culture Scale (WFCS) was designed to assess employee perceptions of the extent to which their organizations facilitates a work-family balance. The WFCS comprises three dimensions: Oorganizational time demands, Managerial support and Negative career consequences. The primary purpose of the present study was to analyze the factor structure and reliability of the Spanish version of the Work-Family Culture Scale in a sample of 795 employees (447 females and 348 males) working for twenty-three firms in the Spanish advertising sector. Both EFA and CFA using split-half data sets yielded an 11-item three-factor model (Managerial support, Career consequences and Organizational time demands) that fits the data very well. The findings for structural equation modeling were as follows: χ(2) (41) = 63.85; CFI = .99; GFI = .97; and RMSEA = .038. Internal consistency for the WFCS factors proved adequate. The results of the analysis indicate that this three-factor model confirms previous exploratory analyses of the original scale.

Factor structure and psychometric properties of a Romanian translation of the Body Appreciation Scale-2.

PubMed

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.

Factor structure and psychometric properties of a Spanish translation of the Body Appreciation Scale-2 (BAS-2).

PubMed

Swami, Viren; García, Antonio Alías; Barron, David

2017-09-01

We examined the psychometric properties of a Spanish translation of the Body Appreciation Scale-2 (BAS-2) in a community sample of 411 women and 389 men in Almería, Spain. Participants completed the 10-item BAS-2 along with measures of appearance evaluation, body areas satisfaction, self-esteem, life satisfaction, and self-reported body mass index (BMI). Exploratory factor analyses with one split-half subsample revealed that BAS-2 scores had a one-dimensional factor structure in women and men. Confirmatory factor analysis with a second split-half subsample showed the one-dimensional factor structure had acceptable fit and was invariant across sex. There were no significant sex differences in BAS-2 scores. BAS-2 scores were significantly and positively correlated with appearance evaluation, body areas satisfaction, self-esteem, and life satisfaction. Body appreciation was significantly and negatively correlated with BMI in men, but associations in women were only significant in the second subsample. Results suggest that the Spanish BAS-2 has adequate psychometric properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Broad Ability Factors in 12- to 13-Year-Old Children, the Theory of Fluid and Crystallized Intelligence, and the Differentiation Hypothesis

ERIC Educational Resources Information Center

Undheim, Johan Olav

1978-01-01

A simple-structure factor analysis of test data from 149 sixth-grade children in Norway was conducted. Broad factors were interpreted to represent Visualization, Speediness, and Fluency, as well as Fluid and Crystallized Intelligence. The results are discussed in relation to the Cattell-Horn theory of intelligence. (Author/JAC)

Structural validity of the Maslach Burnout Inventory and influence of depressive symptoms in banking workplace: Unfastening the occupational conundrum.

PubMed

Valente, Maria do Socorro da Silva; Wang, Yuan-Pang; Menezes, Paulo Rossi

2018-06-04

Burnout and mental disorders have been reported in the financial industry. This study aims to examine the structural validity of the Maslach Burnout Inventory (MBI) and to investigate the connection between the dimensions of burnout and depressive symptoms in a sample of 1046 bank employees from North Brazil who completed the MBI and the Patient Health Questionnaire-9 (PHQ-9. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to cross-check the factorial structure of the MBI. One-way analysis of variance and correlation analysis were applied to elucidate the relationship between burnout and depressive symptoms. Both 3-factor and 4-factor oblique solutions were plausible EFA models of the burnout syndrome. Results of CFA supported the 19-item 4-factor structure as the best fitting model to data, with two exhaustion factors ("exhausted" and "strained"), depersonalization, and personal accomplishment. The PHQ-9 total score and individual score of depressive items were significantly correlated with all MBI dimensions, notably with the emotional exhaustion dimension. The moderate-to-high correlation observed between burnout and depression suggest the potential utility of the MBI for evaluating burnout among bank employees as well as to point out the need to evaluate systematically the burnout and depressive symptoms given to their potential association. Copyright © 2018. Published by Elsevier B.V.

A systematic review of the factor structure and reliability of the Spence Children's Anxiety Scale.

PubMed

Orgilés, Mireia; Fernández-Martínez, Iván; Guillén-Riquelme, Alejandro; Espada, José P; Essau, Cecilia A

2016-01-15

The Spence Children's Anxiety Scale (SCAS) is a widely used instrument for assessing symptoms of anxiety disorders among children and adolescents. Previous studies have demonstrated its good reliability for children and adolescents from different backgrounds. However, remarkable variability in the reliability of the SCAS across studies and inconsistent results regarding its factor structure has been found. The present study aims to examine the SCAS factor structure by means of a systematic review with narrative synthesis, the mean reliability of the SCAS by means of a meta-analysis, and the influence of the moderators on the SCAS reliability. Databases employed to collect the studies included Scholar Google, PsycARTICLES, PsycINFO, Web of Science, and Scopus since 1997. Twenty-nine and 32 studies, which examined the factor structure and the internal consistency of the SCAS, respectively, were included. The SCAS was found to have strong internal consistency, influenced by different moderators. The systematic review demonstrated that the original six-factor model was supported by most studies. Factorial invariance studies (across age, gender, country) and test-retest reliability of the SCAS were not examined in this study. It is concluded that the SCAS is a reliable instrument for cross-cultural use, and it is suggested that the original six-factor model is appropriate for cross-cultural application. Copyright © 2015 Elsevier B.V. All rights reserved.

Determination of ensemble-average pairwise root mean-square deviation from experimental B-factors.

PubMed

Kuzmanic, Antonija; Zagrovic, Bojan

2010-03-03

Root mean-square deviation (RMSD) after roto-translational least-squares fitting is a measure of global structural similarity of macromolecules used commonly. On the other hand, experimental x-ray B-factors are used frequently to study local structural heterogeneity and dynamics in macromolecules by providing direct information about root mean-square fluctuations (RMSF) that can also be calculated from molecular dynamics simulations. We provide a mathematical derivation showing that, given a set of conservative assumptions, a root mean-square ensemble-average of an all-against-all distribution of pairwise RMSD for a single molecular species, (1/2), is directly related to average B-factors () and (1/2). We show this relationship and explore its limits of validity on a heterogeneous ensemble of structures taken from molecular dynamics simulations of villin headpiece generated using distributed-computing techniques and the Folding@Home cluster. Our results provide a basis for quantifying global structural diversity of macromolecules in crystals directly from x-ray experiments, and we show this on a large set of structures taken from the Protein Data Bank. In particular, we show that the ensemble-average pairwise backbone RMSD for a microscopic ensemble underlying a typical protein x-ray structure is approximately 1.1 A, under the assumption that the principal contribution to experimental B-factors is conformational variability. 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.