ERIC Educational Resources Information Center
Hofmann, Rich; Sherman, Larry
Using data from 135 sixth-, seventh-, and eighth-graders between 11 and 15 years old attending a middle school in a suburban Southwest Ohio school district, two hypothesized models of the factor structures for the Coopersmith Self-Esteem Inventory were tested. One model represents the original Coopersmith factor structure, and the other model is…
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.
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.
Schretlen, David J; Peña, Javier; Aretouli, Eleni; Orue, Izaskun; Cascella, Nicola G; Pearlson, Godfrey D; Ojeda, Natalia
2013-06-01
We sought to determine whether a single hypothesized latent factor structure would characterize cognitive functioning in three distinct groups. We assessed 576 adults (340 community controls, 126 adults with bipolar disorder, and 110 adults with schizophrenia) using 15 measures derived from nine cognitive tests. Confirmatory factor analysis (CFA) was conducted to examine the fit of a hypothesized six-factor model. The hypothesized factors included attention, psychomotor speed, verbal memory, visual memory, ideational fluency, and executive functioning. The six-factor model provided an excellent fit for all three groups [for community controls, root mean square error of approximation (RMSEA) <0.048 and comparative fit index (CFI) = 0.99; for adults with bipolar disorder, RMSEA = 0.071 and CFI = 0.99; and for adults with schizophrenia, RMSEA = 0.06 and CFI = 0.98]. Alternate models that combined fluency with processing speed or verbal and visual memory reduced the goodness of fit. Multi-group CFA results supported factor invariance across the three groups. Confirmatory factor analysis supported a single six-factor structure of cognitive functioning among patients with schizophrenia or bipolar disorder and community controls. While the three groups clearly differ in level of performance, they share a common underlying architecture of information processing abilities. These cognitive factors could provide useful targets for clinical trials of treatments that aim to enhance information processing in persons with neurological and neuropsychiatric disorders. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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…
Automatic Bayes Factors for Testing Equality- and Inequality-Constrained Hypotheses on Variances.
Böing-Messing, Florian; Mulder, Joris
2018-05-03
In comparing characteristics of independent populations, researchers frequently expect a certain structure of the population variances. These expectations can be formulated as hypotheses with equality and/or inequality constraints on the variances. In this article, we consider the Bayes factor for testing such (in)equality-constrained hypotheses on variances. Application of Bayes factors requires specification of a prior under every hypothesis to be tested. However, specifying subjective priors for variances based on prior information is a difficult task. We therefore consider so-called automatic or default Bayes factors. These methods avoid the need for the user to specify priors by using information from the sample data. We present three automatic Bayes factors for testing variances. The first is a Bayes factor with equal priors on all variances, where the priors are specified automatically using a small share of the information in the sample data. The second is the fractional Bayes factor, where a fraction of the likelihood is used for automatic prior specification. The third is an adjustment of the fractional Bayes factor such that the parsimony of inequality-constrained hypotheses is properly taken into account. The Bayes factors are evaluated by investigating different properties such as information consistency and large sample consistency. Based on this evaluation, it is concluded that the adjusted fractional Bayes factor is generally recommendable for testing equality- and inequality-constrained hypotheses on variances.
Examining Factorial Validity and Measurement Invariance of the Student-Teacher Relationship Scale
ERIC Educational Resources Information Center
Webb, Mi-young L.; Neuharth-Pritchett, Stacey
2011-01-01
The purposes of this study were to (a) test the hypothesized factor structure of the Student-Teacher Relationship Scale (STRS; Pianta, 2001) for 308 African American (AA) and European American (EA) children using confirmatory factor analysis (CFA) and (b) examine the measurement invariance of the factor structure across AA and EA children. CFA of…
Examining the factor structure of the Multiple Sclerosis Impact Scale.
Fitzgerald, Shawn M; Li, Jian; Rumrill, Phillip D; Merchant, William; Bishop, Malachy
2014-01-01
The purpose of this study was to investigate the factor structure of the Multiple Sclerosis Impact Scale (MSIS-29) to assess its suitability for modeling the impact of MS on a nation-wide sample of individuals from the United States. Investigators completed a Confirmatory Factor Analysis (CFA) to examine the two-factor structure proposed by Hobart et al. [17]. Although the original MSIS-29 factor structure did not fit the data exactly, the hypothesized two-factor model was partially supported in the current data. Implications for future instrument development and rehabilitation practice are discussed.
ERIC Educational Resources Information Center
He, Jian-Ping; Burstein, Marcy; Schmitz, Anja; Merikangas, Kathleen R.
2013-01-01
The Strengths and Difficulties Questionnaire (SDQ) is one of the most commonly used instruments for screening psychopathology in children and adolescents. This study evaluated the hypothesized five-factor structure of the SDQ and examined its convergent validity against comprehensive clinical diagnostic assessments. Data were derived from the…
Factor Structure of ImPACT® in Adolescent Student Athletes.
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 autonomy preference index in people with severe mental illness.
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.
Bayes factors for testing inequality constrained hypotheses: Issues with prior specification.
Mulder, Joris
2014-02-01
Several issues are discussed when testing inequality constrained hypotheses using a Bayesian approach. First, the complexity (or size) of the inequality constrained parameter spaces can be ignored. This is the case when using the posterior probability that the inequality constraints of a hypothesis hold, Bayes factors based on non-informative improper priors, and partial Bayes factors based on posterior priors. Second, the Bayes factor may not be invariant for linear one-to-one transformations of the data. This can be observed when using balanced priors which are centred on the boundary of the constrained parameter space with a diagonal covariance structure. Third, the information paradox can be observed. When testing inequality constrained hypotheses, the information paradox occurs when the Bayes factor of an inequality constrained hypothesis against its complement converges to a constant as the evidence for the first hypothesis accumulates while keeping the sample size fixed. This paradox occurs when using Zellner's g prior as a result of too much prior shrinkage. Therefore, two new methods are proposed that avoid these issues. First, partial Bayes factors are proposed based on transformed minimal training samples. These training samples result in posterior priors that are centred on the boundary of the constrained parameter space with the same covariance structure as in the sample. Second, a g prior approach is proposed by letting g go to infinity. This is possible because the Jeffreys-Lindley paradox is not an issue when testing inequality constrained hypotheses. A simulation study indicated that the Bayes factor based on this g prior approach converges fastest to the true inequality constrained hypothesis. © 2013 The British Psychological Society.
Teacher role stress, satisfaction, commitment, and intentions to leave: a structural model.
Conley, Sharon; You, Sukkyung
2009-12-01
Structural equation modeling was used to assess the plausibility of a conceptual model specifying hypothesized linkages among teachers' perceptions of the role stresses of role ambiguity, role conflict, and role overload and commitment, satisfaction, and intentions to leave their employing school. 178 teachers in four high schools in a southern coastal region of California responded to survey questions designed to capture the above constructs. Confirmatory factor analysis was used to assess whether the role-stress items fit hypothesized constructs. Structural equation modeling results indicated that satisfaction and commitment are two mediators in the role stresses-intentions to leave relationship.
Limiting factors and landscape connectivity: the American marten in the Rocky Mountains
S. A. Cushman; M. G. Raphael; L. F. Ruggiero; A. S. Shirk; T. N. Wasserman; E. C. O' Doherty
2011-01-01
In mobile animals, movement behavior can maximize fitness by optimizing access to critical resources and minimizing risk of predation. We sought to evaluate several hypotheses regarding the effects of landscape structure on American marten foraging path selection in a landscape experiencing forest perforation by patchcut logging. We hypothesized that in the uncut pre-...
ERIC Educational Resources Information Center
Zimmermann, Gregoire; Mahaim, Elodie Biermann; Mantzouranis, Gregory; Genoud, Philippe A.; Crocetti, Elisabetta
2012-01-01
The purpose of this study was to evaluate the factor structure and the reliability of the French versions of the Identity Style Inventory (ISI-3) and the Utrecht-Management of Identity Commitments Scale (U-MICS) in a sample of college students (N = 457, 18-25 years old). Confirmatory factor analyses confirmed the hypothesized three-factor solution…
Graffigna, Guendalina; Bonanomi, Andrea
2017-01-01
Background Increasing bodies of scientific research today examines the factors and interventions affecting patients’ ability to self-manage and adhere to treatment. Patient activation is considered the most reliable indicator of patients’ ability to manage health autonomously. Only a few studies have tried to assess the role of psychosocial factors in promoting patient activation. A more systematic modeling of the psychosocial factors explaining the variance of patient activation is needed. Objective To test the hypothesized effect of patient activation on medication adherence; to test the the hypothesized effects of positive emotions and of the quality of the patient/doctor relationship on patient activation; and to test the hypothesized mediating effect of Patient Health Engagement (PHE-model) in this pathway. Material and methods This cross-sectional study involved 352 Italian-speaking adult chronic patients. The survey included measures of i) patient activation (Patient Activation Measure 13 –short form); ii) Patient Health Engagement model (Patient Health Engagement Scale); iii) patient adherence (4 item-Morinsky Medication Adherence Scale); iv) the quality of the patients’ emotional feelings (Manikin Self Assessment Scale); v) the quality of the patient/doctor relationship (Health Care Climate Questionnaire). Structural equation modeling was used to test the hypotheses proposed. Results According to the theoretical model we hypothesized, research results confirmed that patients’ activation significantly affects their reported medication adherence. Moreover, psychosocial factors, such as the patients’ quality of the emotional feelings and the quality of the patient/doctor relationship were demonstrated to be factors affecting the level of patient activation. Finally, the mediation effect of the Patient Health Engagement model was confirmed by the analysis. Conclusions Consistently with the results of previous studies, these findings demonstrate that the Patient Health Engagement Model is a critical factor in enhancing the quality of care. The Patient Health Engagement Model might acts as a mechanism to increase patient activation and adherence. PMID:28654686
Graffigna, Guendalina; Barello, Serena; Bonanomi, Andrea
2017-01-01
Increasing bodies of scientific research today examines the factors and interventions affecting patients' ability to self-manage and adhere to treatment. Patient activation is considered the most reliable indicator of patients' ability to manage health autonomously. Only a few studies have tried to assess the role of psychosocial factors in promoting patient activation. A more systematic modeling of the psychosocial factors explaining the variance of patient activation is needed. To test the hypothesized effect of patient activation on medication adherence; to test the the hypothesized effects of positive emotions and of the quality of the patient/doctor relationship on patient activation; and to test the hypothesized mediating effect of Patient Health Engagement (PHE-model) in this pathway. This cross-sectional study involved 352 Italian-speaking adult chronic patients. The survey included measures of i) patient activation (Patient Activation Measure 13 -short form); ii) Patient Health Engagement model (Patient Health Engagement Scale); iii) patient adherence (4 item-Morinsky Medication Adherence Scale); iv) the quality of the patients' emotional feelings (Manikin Self Assessment Scale); v) the quality of the patient/doctor relationship (Health Care Climate Questionnaire). Structural equation modeling was used to test the hypotheses proposed. According to the theoretical model we hypothesized, research results confirmed that patients' activation significantly affects their reported medication adherence. Moreover, psychosocial factors, such as the patients' quality of the emotional feelings and the quality of the patient/doctor relationship were demonstrated to be factors affecting the level of patient activation. Finally, the mediation effect of the Patient Health Engagement model was confirmed by the analysis. Consistently with the results of previous studies, these findings demonstrate that the Patient Health Engagement Model is a critical factor in enhancing the quality of care. The Patient Health Engagement Model might acts as a mechanism to increase patient activation and adherence.
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.
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…
The self as a mediator between personality and adjustment.
Graziano, W G; Jensen-Campbell, L A; Finch, J F
1997-08-01
The self can be conceptualized as a mediating agent that translates personality into situated goal-directed activities and adaptation. This research used a level-of-analysis approach to link personality dimensions (Level I) to self-systems (Level II) and to teacher ratings of adjustment in African American, Mexican American, and European American students (N = 317). The authors hypothesized that links among aspects of self-esteem and teacher ratings of adjustment would be domain specific, and those links to dimensions of the 5-factor model would reflects the domain specificity. Structural equation modeling corroborated hypotheses about domain specificity in links between adjustment and 5-factor dimensions. Results were discussed in terms of levels of analysis for personality structure, personality development, and age-related adaptations to social contexts.
Multilevel Multi-Informant Structure of the Authoritative School Climate Survey
ERIC Educational Resources Information Center
Konold, Timothy; Cornell, Dewey; Huang, Francis; Meyer, Patrick; Lacey, Anna; Nekvasil, Erin; Heilbrun, Anna; Shukla, Kathan
2014-01-01
The Authoritative School Climate Survey was designed to provide schools with a brief assessment of 2 key characteristics of school climate--disciplinary structure and student support--that are hypothesized to influence 2 important school climate outcomes--student engagement and prevalence of teasing and bullying in school. The factor structure of…
Lac, Andrew; Alvaro, Eusebio M; Crano, William D; Siegel, Jason T
2009-03-01
Despite research indicating that effective parenting plays an important protective role in adolescent risk behaviors, few studies have applied theory to examine this link with marijuana use, especially with national data. In the current study (N = 2,141), we hypothesized that parental knowledge (of adolescent activities and whereabouts) and parental warmth are antecedents of adolescents' marijuana beliefs-attitudes, subjective norms, and perceived behavioral control-as posited by the Theory of Planned Behavior (TPB; Ajzen 1991). These three types of beliefs were hypothesized to predict marijuana intention, which in turn was hypothesized to predict marijuana consumption. Results of confirmatory factor analyses corroborated the psychometric properties of the two-factor parenting structure as well as the five-factor structure of the TPB. Further, the proposed integrative predictive framework, estimated with a latent structural equation model, was largely supported. Parental knowledge inversely predicted pro-marijuana attitudes, subjective norms, and perceived behavioral control; parental warmth inversely predicted pro-marijuana attitudes and subjective norms, ps < .001. Marijuana intention (p < .001), but not perceived behavioral control, predicted marijuana use 1 year later. In households with high parental knowledge, parental warmth also was perceived to be high (r = .54, p < .001). Owing to the analysis of nationally representative data, results are generalizable to the United States population of adolescents 12-18 years of age.
Alcaraz-Ibáñez, Manuel; Sicilia, Alvaro
2018-06-01
This study examined the psychometric properties of a Spanish translation of the Body and Appearance Self-Conscious Emotions Scale (BASES; Castonguay et al., 2014) in a sample of university Spanish students. A total of 815 participants enrolled in two public universities located in Almería and Elche, Spain, completed the BASES along with measures of social physique anxiety and positive/negative affect. Exploratory and confirmatory factor analyses showed that one item failed to load clearly on the hypothesized factor (guilt). Once it was removed, results supported the hypothesized four-factor structure. Evidence of invariance of the four-factor structure across sex was obtained. Scores on the BASES showed adequate internal consistency and acceptable convergent validity. Compared to men, women reported significantly higher body and appearance-related guilt and shame, and significant lower authentic and hubristic pride. Preliminary evidence supporting the validity and reliability of the Spanish translation of the BASES is provided. Copyright © 2018 Elsevier Ltd. All rights reserved.
The Columbia Impairment Scale: Factor Analysis Using a Community Mental Health Sample
ERIC Educational Resources Information Center
Singer, Jonathan B.; Eack, Shaun M.; Greeno, Catherine M.
2011-01-01
Objective: The objective of this study was to test the factor structure of the parent version of the Columbia Impairment Scale (CIS) in a sample of mothers who brought their children for community mental health (CMH) services (n = 280). Method: Confirmatory factor analysis (CFA) was used to test the fit of the hypothesized four-factor structure…
ERIC Educational Resources Information Center
Fischer, Judith L.; Forthun, Larry F.; Pidcock, Boyd W.; Dowd, Duane A.
2007-01-01
This study tested associations between problems in parent-youth relationships and problems with alcohol use among college students (N = 1592) using structural equation modeling. Hypotheses were that relationships between both substance-specific parenting factors (parental drinking) and non-substance-specific parenting factors (parental intrusive…
WAIS-IV Subtest Covariance Structure: Conceptual and Statistical Considerations
ERIC Educational Resources Information Center
Ward, L. Charles; Bergman, Maria A.; Hebert, Katina R.
2012-01-01
D. Wechsler (2008b) reported confirmatory factor analyses (CFAs) with standardization data (ages 16-69 years) for 10 core and 5 supplemental subtests from the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV). Analyses of the 15 subtests supported 4 hypothesized oblique factors (Verbal Comprehension, Working Memory, Perceptual Reasoning,…
NASA Astrophysics Data System (ADS)
Ab Hamid, Mohd Rashid; Mustafa, Zainol; Mohd Suradi, Nur Riza; Idris, Fazli; Abdullah, Mokhtar
2013-04-01
Culture and employee-focused criteria are important factors for the success of any organization. These factors have to be aligned with the productivity initiatives in the organization in order to gear ahead for excellence. Therefore, this article investigated the impact of culture and employee-focused criteria on productivity in Higher Education Institutions (HEIs) in Malaysia using intangible indicators through core values. The hypothesized relationship was tested using Structural Equation Modeling (SEM) with the PLS estimation technique. 429 questionnaires were returned from the target population. The results of the modelling revealed that the PLS estimation confirmed all the hypotheses tested as in the hypothesized model. The results generally support significant relationships between culture values, employee-focused values and productivity-focused values. The study also confirmed the mediating role of employee-focused values for the relationship between culture values and productivity-focused values. In conclusion, the empirically validated results supported the adequacy of the hypothezised model of the impact of culture and employee-focused criteria on productivity in HEI through value-based indicators.
Tapsoba, H; Deschamps, J P; Leclercq, M H
2000-01-01
A questionnaire designed to measure oral health-related quality of life (OHRQOL) in adults and children was assessed for its factorial structure and reliability using data from the Second International Collaborative Study on Oral Health Outcomes in New Zealand, Poland and Germany. Principal component analysis with orthogonal and oblique rotation was applied. The three-factor structure hypothesized for the children's questionnaire (self-reported oral disease symptoms, perceived oral well-being, social and physical functioning) was confirmed in New Zealand and Poland, and two self-reported oral disease symptom dimensions emerged in Germany. Five factors instead of the three hypothesized were identified for adults: two dimensions of symptoms were identified, and social and physical functioning appeared to be independent dimensions of OHRQOL. Similarity between the factors was demonstrated in all three countries. The reliability of the questionnaire ranged from moderate to excellent depending on the dimension and the country. These findings provide preliminary evidence of the cross-cultural stability of the OHRQOL questionnaire in New Zealand, Poland and Germany, for both children and adults. Further investigations by the present authors of the properties of the instrument in other samples will focus on demonstrating the stability and replicability of the factor structure identified here.
ERIC Educational Resources Information Center
Newcomb, Michael D.; Abbott, Robert D.; Catalano, Richard F.; Hawkins, J. David; Battin-Pearson, Sara; Hill, Karl
2002-01-01
Understanding and preventing high school failure is a national priority. Structural strain and general deviance theories attempt to explain late high school failure. The authors tested the hypotheses that general (vs. specific) deviance and academic competence mediate the relationships between structural strain factors (gender, ethnicity, and…
ERIC Educational Resources Information Center
Middleton, James A.
2013-01-01
The role of mathematical interest, identity, utility, self-efficacy, and effort was examined as a set of interdependent factors leading to students' mathematics achievement. A structural equations model, testing a hypothesized structure of motivation variables and their impact on middle school mathematics achievement was developed utilizing the…
Dissociative absorption: An empirically unique, clinically relevant, dissociative factor.
Soffer-Dudek, Nirit; Lassri, Dana; Soffer-Dudek, Nir; Shahar, Golan
2015-11-01
Research of dissociative absorption has raised two questions: (a) Is absorption a unique dissociative factor within a three-factor structure, or a part of one general dissociative factor? Even when three factors are found, the specificity of the absorption factor is questionable. (b) Is absorption implicated in psychopathology? Although commonly viewed as "non-clinical" dissociation, absorption was recently hypothesized to be specifically associated with obsessive-compulsive symptoms. To address these questions, we conducted exploratory and confirmatory factor analyses on 679 undergraduates. Analyses supported the three-factor model, and a "purified" absorption scale was extracted from the original inclusive absorption factor. The purified scale predicted several psychopathology scales. As hypothesized, absorption was a stronger predictor of obsessive-compulsive symptoms than of general psychopathology. In addition, absorption was the only dissociative scale that longitudinally predicted obsessive-compulsive symptoms. We conclude that absorption is a unique and clinically relevant dissociative tendency that is particularly meaningful to obsessive-compulsive symptoms. Copyright © 2015 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Ausderau, Karla; Sideris, John; Furlong, Melissa; Little, Lauren M.; Bulluck, John; Baranek, Grace T.
2014-01-01
This national online survey study characterized sensory features in 1,307 children with autism spectrum disorder (ASD) ages 2-12 years using the Sensory Experiences Questionnaire Version 3.0 (SEQ-3.0). Using the SEQ-3.0, a confirmatory factor analytic model with four substantive factors of hypothesized sensory response patterns (i.e.,…
Classification and reduction of pilot error
NASA Technical Reports Server (NTRS)
Rogers, W. H.; Logan, A. L.; Boley, G. D.
1989-01-01
Human error is a primary or contributing factor in about two-thirds of commercial aviation accidents worldwide. With the ultimate goal of reducing pilot error accidents, this contract effort is aimed at understanding the factors underlying error events and reducing the probability of certain types of errors by modifying underlying factors such as flight deck design and procedures. A review of the literature relevant to error classification was conducted. Classification includes categorizing types of errors, the information processing mechanisms and factors underlying them, and identifying factor-mechanism-error relationships. The classification scheme developed by Jens Rasmussen was adopted because it provided a comprehensive yet basic error classification shell or structure that could easily accommodate addition of details on domain-specific factors. For these purposes, factors specific to the aviation environment were incorporated. Hypotheses concerning the relationship of a small number of underlying factors, information processing mechanisms, and error types types identified in the classification scheme were formulated. ASRS data were reviewed and a simulation experiment was performed to evaluate and quantify the hypotheses.
Tomko, Rachel L; Prisciandaro, James J; Falls, Sandhya Kutty; Magid, Viktoriya
2016-04-01
A youth version of the UPPS Impulsivity Scale (UPPS-R-C) was previously shown to predict drinking initiation among pre-adolescents. The goals of the current study were to confirm the structure of the UPPS-R-C using a sample of treatment-seeking adolescents and to examine the scales' relations with alcohol use, marijuana use, and problems related to substance use. Participants (N=120; ages 12-18; M=15.7) completed questionnaires at treatment intake. Confirmatory factor analysis (CFA) of the UPPS-R-C was conducted using a 5-factor model with factors corresponding to negative urgency, positive urgency, lack of perseverance, lack of premeditation, and sensation seeking. Relations between UPPS-R-C factors and binge drinking, marijuana use, and problems resulting from substance use were examined using path analysis. CFA suggested the 5-factor model provided adequate fit to the data. The hypothesized path model was partially supported, positive urgency was associated with frequency of binge drinking, and both negative urgency and frequency of binge drinking was associated with problems due to substance use. Other hypothesized paths were not significant. Although not hypothesized, negative urgency was associated with frequency of marijuana use and lack of perseverance was associated with problems due to use. Results suggest that the UPPS-R-C can be used with a treatment-seeking sample of adolescents. Furthermore, negative urgency, positive urgency, and lack of perseverance may be indicative of more severe substance use problems in a treatment setting. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Prisciandaro, James J.; Kutty Falls, Sandhya; Magid, Viktoriya
2016-01-01
Background A youth version of the UPPS Impulsivity Scale (UPPS-R-C) was previously shown to predict drinking initiation among pre-adolescents. The goals of the current study were to confirm the structure of the UPPS-R-C using a sample of treatment-seeking adolescents and to examine the scales’ relations with alcohol use, marijuana use, and problems related to substance use. Method Participants (N = 120; ages 12–18; M = 15.7) completed questionnaires at treatment intake. Confirmatory factor analysis (CFA) of the UPPS-R-C was conducted using a 5-factor model with factors corresponding to negative urgency, positive urgency, lack of perseverance, lack of premeditation, and sensation seeking. Relations between UPPS-R-C factors and binge drinking, marijuana use, and problems resulting from substance use were examined using path analysis. Results CFA suggested the 5-factor model provided adequate fit to the data. The hypothesized path model was partially supported, positive urgency was associated with frequency of binge drinking, and both negative urgency and frequency of binge drinking was associated with problems due to substance use. Other hypothesized paths were not significant. Although not hypothesized, negative urgency was associated with frequency of marijuana use and lack of perseverance was associated with problems due to use. Conclusions Results suggest that the UPPS-R-C can be used with a treatment-seeking sample of adolescents. Furthermore, negative urgency, positive urgency, and lack of perseverance may be indicative of more severe substance use problems in a treatment setting. PMID:26905208
Rolefulness: Social and Internal Sense of Role Satisfaction
ERIC Educational Resources Information Center
Kato, Daiki; Suzuki, Mikie
2018-01-01
The main purpose of this study is to hypothesize the existence of the general sense of role satisfaction and device a scale to measure it. The participants in study 1 were 1029 Japanese high school students (484 men and 545 women). The result of exploratory factor analysis suggested that the two-factor structure is adequate. One is "social…
Parasitism and generation cycles in a salt-marsh planthopper
John D. Reeve; James T. Cronin; Donald R. Strong
1994-01-01
1. In warm climates many insects exhibit discrete generations, in the absence of obvious factors that could synchronize their age structure.It has been hypothesized that parasitoid wasps might be responsible for these oscillations in the host age structure, known as generation cycles. 2. We examine the role of the parasitoid Anagrus delicatus in the dynamics of the...
ERIC Educational Resources Information Center
Huang, Francis L.; Cornell, Dewey G.; Konold, Timothy; Meyer, Joseph P.; Lacey, Anna; Nekvasil, Erin K.; Heilbrun, Anna; Shukla, Kathan D.
2015-01-01
Background: School climate is well recognized as an important influence on student behavior and adjustment to school, but there is a need for theory-guided measures that make use of teacher perspectives. Authoritative school climate theory hypothesizes that a positive school climate is characterized by high levels of disciplinary structure and…
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.
Multilevel multi-informant structure of the authoritative school climate survey.
Konold, Timothy; Cornell, Dewey; Huang, Francis; Meyer, Patrick; Lacey, Anna; Nekvasil, Erin; Heilbrun, Anna; Shukla, Kathan
2014-09-01
The Authoritative School Climate Survey was designed to provide schools with a brief assessment of 2 key characteristics of school climate--disciplinary structure and student support--that are hypothesized to influence 2 important school climate outcomes--student engagement and prevalence of teasing and bullying in school. The factor structure of these 4 constructs was examined with exploratory and confirmatory factor analyses in a statewide sample of 39,364 students (Grades 7 and 8) attending 423 schools. Notably, the analyses used a multilevel structural approach to model the nesting of students in schools for purposes of evaluating factor structure, demonstrating convergent and concurrent validity and gauging the structural invariance of concurrent validity coefficients across gender. These findings provide schools with a core group of school climate measures guided by authoritative discipline theory. PsycINFO Database Record (c) 2014 APA, all rights reserved.
Neighborhoods as a Power Factor.
ERIC Educational Resources Information Center
Woody, Bette; And Others
1980-01-01
Examines Washington, DC, Advisory Neighborhood Commissions (ANC) as an illustration of neighborhood involvement in city revitalization and maintenance. Considers (1) hypotheses about neighborhood roles and participation in public issue raising; (2) ANC structure, participation, and decision roles; and (3) likely roles neighborhood governments can…
ERIC Educational Resources Information Center
Shin, Huiyoung; Ryan, Allison M.
2012-01-01
This study investigated individual differences in sixth-grade students (N = 181; 47% girls, ethnically diverse) use of friends as a coping resource when dealing with a social stressor with another peer at school. Confirmatory factor analysis supported the hypothesized three factor structure of coping with friends: mastery, avoidance, and…
ERIC Educational Resources Information Center
Park, Yujeong; Benedict, Amber E.; Brownell, Mary T.
2014-01-01
The factor structure of the CORE Phonics Survey was analyzed using a sample of 165 students in upper elementary school with specific learning disabilities. Confirmatory factor analysis was used to identify the hypothesized constructs of the CORE Phonics Survey and predictive validity of the CORE Phonics Survey to predict students' success in word…
Boamah, Sheila A; Read, Emily A; Spence Laschinger, Heather K
2017-05-01
To test a hypothesized model linking new graduate nurses' perceptions of their manager's authentic leadership behaviours to structural empowerment, short-staffing and work-life interference and subsequent burnout, job satisfaction and patient care quality. Authentic leadership and structural empowerment have been shown to reduce early career burnout among nurses. Short-staffing and work-life interference are also linked to burnout and may help explain the impact of positive, empowering leadership on burnout, which in turn influences job satisfaction and patient care quality. A time-lagged study of Canadian new graduate nurses was conducted. At Time 1, surveys were sent to 3,743 nurses (November 2012-March 2013) and 1,020 were returned (27·3% response rate). At Time 2 (May-July 2014), 406 nurses who responded at Time 1 completed surveys (39·8% response rate). Descriptive analysis was conducted in SPSS. Structural equation modelling in Mplus was used to test the hypothesized model. The hypothesized model was supported. Authentic leadership had a significant positive effect on structural empowerment, which in turn decreased both short-staffing and work-life interference. Short-staffing and work-life imbalance subsequently resulted in nurse burnout, lower job satisfaction and lower patient care quality 1 year later. The findings suggest that short-staffing and work-life interference are important factors influencing new graduate nurse burnout. Developing nurse managers' authentic leadership behaviours and working with them to create and sustain empowering work environments may help reduce burnout, increase nurse job satisfaction and improve patient care quality. © 2016 John Wiley & Sons Ltd.
Hoyle, R H
1991-02-01
Indirect measures of psychological constructs are vital to clinical research. On occasion, however, the meaning of indirect measures of psychological constructs is obfuscated by statistical procedures that do not account for the complex relations between items and latent variables and among latent variables. Covariance structure analysis (CSA) is a statistical procedure for testing hypotheses about the relations among items that indirectly measure a psychological construct and relations among psychological constructs. This article introduces clinical researchers to the strengths and limitations of CSA as a statistical procedure for conceiving and testing structural hypotheses that are not tested adequately with other statistical procedures. The article is organized around two empirical examples that illustrate the use of CSA for evaluating measurement models with correlated error terms, higher-order factors, and measured and latent variables.
The dominant firm in health insurance.
Goldberg, L G; Greenberg, W
1985-01-01
Blue Cross, the largest insurer of hospital costs in most parts of the U.S., has a varying market share by area. This paper examines the factors affecting the market share of Blue Cross by state. The regression analysis finds that the Blue Cross discount has an important impact upon market structure and that certain regulatory factors have had an impact while others, such as the premium tax, have not. Hypotheses related to the effects of consumer demand and the structure of the industry on Blue Cross market share are also tested and largely rejected.
Knowledge discovery from structured mammography reports using inductive logic programming.
Burnside, Elizabeth S; Davis, Jesse; Costa, Victor Santos; Dutra, Inês de Castro; Kahn, Charles E; Fine, Jason; Page, David
2005-01-01
The development of large mammography databases provides an opportunity for knowledge discovery and data mining techniques to recognize patterns not previously appreciated. Using a database from a breast imaging practice containing patient risk factors, imaging findings, and biopsy results, we tested whether inductive logic programming (ILP) could discover interesting hypotheses that could subsequently be tested and validated. The ILP algorithm discovered two hypotheses from the data that were 1) judged as interesting by a subspecialty trained mammographer and 2) validated by analysis of the data itself.
Structural Genomics of Bacterial Virulence Factors
2006-05-01
positioned in the unit cell by Molecular Replacement (Protein Data Bank ( PDB ) ID code 1acc)6 using MOLREP, and refined with REFMAC version 5.0 (ref. 24...increase our understanding of the molecular mechanisms of pathogenicity, putting us in a stronger position to anticipate and react to emerging...term, the accumulated structural information will generate important and testable hypotheses that will increase our understanding of the molecular
BUREAUCRATIC STRUCTURE AND DECISIONMAKING.
ERIC Educational Resources Information Center
DOWNS, ANTHONY
ASPECTS OF ORGANIZATION THEORY ARE REVIEWED ANALYTICALLY TO DEVELOP THE IMPLICATIONS OF THREE MAJOR HYPOTHESES DEFINING THE RELATIONSHIP OF BUREAUS AND BUREAUCRATIC OFFICIALS TO THE DECISIONMAKING PROCESS IN A REALISTIC WORLD WHERE INFORMATION IS COSTLY AND UNCERTAINTY IS AN IMPORTANT FACTOR IN MAKING DECISIONS--(1) BUREAUCRATIC OFFICIALS SEEK TO…
ERIC Educational Resources Information Center
Smith, Gregory C.; Palmieri, Patrick A.; Hancock, Gregory R.; Richardson, Rhonda A.
2008-01-01
An adaptation of the Family Stress Model (FSM) with hypothesized linkages between family contextual factors, custodial grandmothers' psychological distress, parenting practices, and grandchildren's adjustment was tested with structural equation modeling. Interview data from 733 custodial grandmothers of grandchildren between ages 4-17 revealed…
Figueiredo-Ferraz, Hugo; Gil-Monte, Pedro R; Grau-Alberola, Ester; Llorca-Pellicer, Marta; García-Juesas, Juan A
2012-09-01
The problem of mobbing has attracted a great deal of attention over the past few years. This concern has increased the study of the phenomena, which has resulted in many scientific publications. Mobbing has been characterized as an emerging risk at work. The aim of this study was to analyse the influence of some psychosocial factors at work - role clarity, interpersonal conflicts and social support - on mobbing and its consequences - that is, inclination towards absenteeism and psychosomatic disorders. The sample included 422 employees working with people with intellectual disabilities. Structural equation modelling (SEM) was used to test the hypotheses. The Hypothesized model showed an adequate fit to data, and all hypothesized relationships were significant. The results of this study provide support for the mediator role of mobbing in the relationship between high role ambiguity, low social support and high interpersonal conflicts and psychosomatic disorders and inclination towards absenteeism. © 2012 Blackwell Publishing Ltd.
Confirmatory factor analysis of posttraumatic stress symptoms in sexually harassed women.
Palmieri, Patrick A; Fitzgerald, Louise F
2005-12-01
Posttraumatic stress disorder (PTSD) factor analytic research to date has not provided a clear consensus on the structure of posttraumatic stress symptoms. Seven hypothesized factor structures were evaluated using confirmatory factor analysis of the Posttraumatic Stress Disorder Checklist, a paper-and-pencil measure of posttraumatic stress symptom severity, in a sample of 1,218 women who experienced a broad range of workplace sexual harassment. The model specifying correlated re-experiencing, effortful avoidance, emotional numbing, and hyperarousal factors provided the best fit to the data. Virtually no support was obtained for the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV; American Psychiatric Association, 1994) three-factor model of re-experiencing, avoidance, and hyperarousal factors. Different patterns of correlations with external variables were found for the avoidance and emotional numbing factors, providing further validation of the supported model.
Factors Influencing Learning of Classical Mechanics.
ERIC Educational Resources Information Center
Champagne, Audrey B.; And Others
Beginning college physics students' misconceptions about moving objects, their mathematics skills, and formal reasoning ability, are all believed to be related to their achievement in physics. It is hypothesized that students whose knowledge structures include misconceptions that are in conflict with concepts in the lectures and text will have…
Factor Structure of a Sluggish Cognitive Tempo Scale in Clinically-Referred Children
ERIC Educational Resources Information Center
Jacobson, Lisa A.; Murphy-Bowman, Sarah C.; Pritchard, Alison E.; Tart-Zelvin, Ariana; Zabel, T. Andrew; Mahone, E. Mark
2012-01-01
"Sluggish cognitive tempo" (SCT) is a construct hypothesized to describe a constellation of behaviors that includes daydreaming, lethargy, drowsiness, difficulty sustaining attention, and underactivity. Although the construct has been inconsistently defined, measures of SCT have shown associations with symptoms of attention-deficit/hyperactivity…
An ecological model of intimate partner violence perpetration at different levels of severity.
Smith Slep, Amy M; Foran, Heather M; Heyman, Richard E
2014-08-01
Intimate partner violence (IPV) is a significant public health concern. This study proposed and tested an ecological model of both general and clinically significant (i.e., injurious or fear-evoking) IPV perpetration (IPVPerp). Risk and promotive factors from multiple ecological levels of influence (i.e., individual, family, workplace, community) were hypothesized to be important in the prediction of IPVPerp. Although clinically significant IPVPerp and general IPVPerp were hypothesized to relate, specific risks for clinically significant IPVPerp were hypothesized. U.S. Air Force active duty members and civilian spouses (N = 34,861 men; 24,331 women) from 82 sites worldwide completed the 2006 Community Assessment, an anonymous online survey assessing IPVPerp along with a variety of potential risk and promotive factors. Final structural equation models for men and women, cross-validated in holdout samples, clearly supported the relevance of an ecological approach to IPVPerp. Factors from all 4 levels were associated with both general IPVPerp and clinically significant IPVPerp, with relatively distal community and workplace factors operating via more proximal individual and family level variables (e.g., relationship satisfaction). The results suggest a variety of both established and novel potential targets for indirectly targeting general and clinically significant IPVPerp by improving risk profiles at the individual, family, workplace, and community levels.
Levant, Ronald F; McDermott, Ryon C; Hewitt, Amber A; Alto, Kathleen M; Harris, Kyle T
2016-10-01
Confirmatory factor analysis of responses to the Male Role Norms Inventory-Adolescent-revised (MRNI-A-r) from 384 middle school students (163 boys, 221 girls) indicated that the best fit to the data was a bifactor model incorporating the hypothesized 3-factor structure while explicitly modeling an additional, general factor. Specifically, each item-level indicator loaded simultaneously on 2 factors: a general traditional masculinity ideology factor and a specific factor corresponding to 1 of the 3 hypothesized masculine norms for adolescents: Emotionally Detached Dominance, Toughness, and Avoidance of Femininity. Invariance testing across gender supported metric invariance for the general factor only. Although item loadings on the general factor were similar across boys and girls, the specific factor loadings varied substantially, with many becoming nonsignificant in the presence of the general factor for girls. A structural regression analysis predicting latent variables of the Meanings of Adolescent Masculinity Scale (MAMS), the Rosenberg Self-esteem Scale, and the Discipline, School Difficulties, and Positive Behavior Scale (DSDPBS) indicated that the general factor was a strong predictor of MAMS for both genders and DSDPBS for girls. Findings indicate that the MRNI-A-r general factor is a valid and reliable indicator of overall internalization of traditional masculinity ideology in adolescents; however, the specific factors may have different meanings for boys as compared with girls and lack validity in the presence of the general factor. These findings are consistent with a developmental perspective of gender ideology that views adolescence as a time when a differentiated cognitive schema of masculine norms is beginning to develop. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Dimensions and categories: the "big five" factors and the DSM personality disorders.
Morey, L C; Gunderson, J; Quigley, B D; Lyons, M
2000-09-01
The five-factor model of personality, which has been widely studied in personality psychology, has been hypothesized to have specific relevance for DSM-defined personality disorders. To evaluate hypothesized relationships of the five-factor model of personality to personality disorders, 144 patients with personality disorders (diagnosed via a structured interview) completed an inventory to assess the five-factor model. Results indicated that the majority of the personality disorders can be differentiated in theoretically predictable ways using the five-factor model of personality. However, while the personality disorders as a whole appear to be differentiable from normal personality functioning on the five factors, the patterns are quite similar across the disorders, a finding that may provide some insight into the general nature of personality pathology but may also suggest problems with discriminant validity. Third, it does not appear that considering disorders as special combinations of features (as might be expected in some categorical models) is more informative than considering them as the sum of certain features (as might be expected in a dimensional model).
Structural equation modeling for observational studies
Grace, J.B.
2008-01-01
Structural equation modeling (SEM) represents a framework for developing and evaluating complex hypotheses about systems. This method of data analysis differs from conventional univariate and multivariate approaches familiar to most biologists in several ways. First, SEMs are multiequational and capable of representing a wide array of complex hypotheses about how system components interrelate. Second, models are typically developed based on theoretical knowledge and designed to represent competing hypotheses about the processes responsible for data structure. Third, SEM is conceptually based on the analysis of covariance relations. Most commonly, solutions are obtained using maximum-likelihood solution procedures, although a variety of solution procedures are used, including Bayesian estimation. Numerous extensions give SEM a very high degree of flexibility in dealing with nonnormal data, categorical responses, latent variables, hierarchical structure, multigroup comparisons, nonlinearities, and other complicating factors. Structural equation modeling allows researchers to address a variety of questions about systems, such as how different processes work in concert, how the influences of perturbations cascade through systems, and about the relative importance of different influences. I present 2 example applications of SEM, one involving interactions among lynx (Lynx pardinus), mongooses (Herpestes ichneumon), and rabbits (Oryctolagus cuniculus), and the second involving anuran species richness. Many wildlife ecologists may find SEM useful for understanding how populations function within their environments. Along with the capability of the methodology comes a need for care in the proper application of SEM.
Lee, Jeong-Won; Lee, Kyung-Eun; Park, Dong-Jin; Kim, Seong-Ho; Nah, Seong-Su; Lee, Ji Hyun; Kim, Seong-Kyu; Lee, Yeon-Ah; Hong, Seung-Jae; Kim, Hyun-Sook; Lee, Hye-Soon; Kim, Hyoun Ah; Joung, Chung-Il; Kim, Sang-Hyon; Lee, Shin-Seok
2017-01-01
Health-related quality of life (HRQOL) in patients with fibromyalgia (FM) is lower than in patients with other chronic diseases and the general population. Although various factors affect HRQOL, no study has examined a structural equation model of HRQOL as an outcome variable in FM patients. The present study assessed relationships among physical function, social factors, psychological factors, and HRQOL, and the effects of these variables on HRQOL in a hypothesized model using structural equation modeling (SEM). HRQOL was measured using SF-36, and the Fibromyalgia Impact Questionnaire (FIQ) was used to assess physical dysfunction. Social and psychological statuses were assessed using the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI), the Arthritis Self-Efficacy Scale (ASES), and the Social Support Scale. SEM analysis was used to test the structural relationships of the model using the AMOS software. Of the 336 patients, 301 (89.6%) were women with an average age of 47.9±10.9 years. The SEM results supported the hypothesized structural model (χ2 = 2.336, df = 3, p = 0.506). The final model showed that Physical Component Summary (PCS) was directly related to self-efficacy and inversely related to FIQ, and that Mental Component Summary (MCS) was inversely related to FIQ, BDI, and STAI. In our model of FM patients, HRQOL was affected by physical, social, and psychological variables. In these patients, higher levels of physical function and self-efficacy can improve the PCS of HRQOL, while physical function, depression, and anxiety negatively affect the MCS of HRQOL.
Lee, Jeong-Won; Lee, Kyung-Eun; Park, Dong-Jin; Kim, Seong-Ho; Nah, Seong-Su; Lee, Ji Hyun; Kim, Seong-Kyu; Lee, Yeon-Ah; Hong, Seung-Jae; Kim, Hyun-Sook; Lee, Hye-Soon; Kim, Hyoun Ah; Joung, Chung-Il; Kim, Sang-Hyon
2017-01-01
Objective Health-related quality of life (HRQOL) in patients with fibromyalgia (FM) is lower than in patients with other chronic diseases and the general population. Although various factors affect HRQOL, no study has examined a structural equation model of HRQOL as an outcome variable in FM patients. The present study assessed relationships among physical function, social factors, psychological factors, and HRQOL, and the effects of these variables on HRQOL in a hypothesized model using structural equation modeling (SEM). Methods HRQOL was measured using SF-36, and the Fibromyalgia Impact Questionnaire (FIQ) was used to assess physical dysfunction. Social and psychological statuses were assessed using the Beck Depression Inventory (BDI), the State-Trait Anxiety Inventory (STAI), the Arthritis Self-Efficacy Scale (ASES), and the Social Support Scale. SEM analysis was used to test the structural relationships of the model using the AMOS software. Results Of the 336 patients, 301 (89.6%) were women with an average age of 47.9±10.9 years. The SEM results supported the hypothesized structural model (χ2 = 2.336, df = 3, p = 0.506). The final model showed that Physical Component Summary (PCS) was directly related to self-efficacy and inversely related to FIQ, and that Mental Component Summary (MCS) was inversely related to FIQ, BDI, and STAI. Conclusions In our model of FM patients, HRQOL was affected by physical, social, and psychological variables. In these patients, higher levels of physical function and self-efficacy can improve the PCS of HRQOL, while physical function, depression, and anxiety negatively affect the MCS of HRQOL. PMID:28158289
Smoking Onset among Teens: An Empirical Analysis of Initial Situations.
ERIC Educational Resources Information Center
Friedman, Larry S.; And Others
This study attempted to identify factors associated with smoking onset among teens. It was hypothesized that initial cigarette smoking is largely prompted by peers, and that these prompts and subsequent social reinforcement may account for smoking participation. An in-depth structured interview investigating the first three smoking or smoking…
Figure Structure, Figure Action, and Framing in Drawings by American and Egyptian Children.
ERIC Educational Resources Information Center
Wilson, Brent; Wilson, Marjorie
1979-01-01
The purpose of this study is to investigate the interaction of biological unfolding and culturally related factors on sequences of narrative figure drawings by American and Egyptian elementary students. Findings support hypotheses relating to the interaction of natural and nurtural influences on children's drawings. (Author/SJL)
Impact of Scaffolding and Question Structure on the Gender Gap
ERIC Educational Resources Information Center
Dawkins, Hillary; Hedgeland, Holly; Jordan, Sally
2017-01-01
We address previous hypotheses about possible factors influencing the gender gap in attainment in physics. Specifically, previous studies claim that scaffolding may preferentially benefit female students, and we present some alternative conclusions surrounding this hypothesis. By taking both student attainment level and the degree of question…
Guo, Rui; Tao, Lan; Yan, Liang; Chen, Lianfang; Wang, Haijun
2014-09-01
From corporate internal governance structure and external institutional environment, this study uses a legitimacy perspective of intuitional theory to analyze the main influence factors on corporate environmental protection inputs and propose some hypotheses. With the establishment of empirical models, it analyzes the data of 2004-2009 listed biological and other companies in China to test the hypotheses. The findings are concluded that in internal institutional environment, the nature of the controlling shareholder, the proportion of the first shareholder in the ownership structure, the combination of chairman and general manager in board efficiency and the intensity of environmental laws and regulations of the industry in external institutional environment have an significant impact on the behaviors of corporate environmental protection inputs.
Approximated adjusted fractional Bayes factors: A general method for testing informative hypotheses.
Gu, Xin; Mulder, Joris; Hoijtink, Herbert
2018-05-01
Informative hypotheses are increasingly being used in psychological sciences because they adequately capture researchers' theories and expectations. In the Bayesian framework, the evaluation of informative hypotheses often makes use of default Bayes factors such as the fractional Bayes factor. This paper approximates and adjusts the fractional Bayes factor such that it can be used to evaluate informative hypotheses in general statistical models. In the fractional Bayes factor a fraction parameter must be specified which controls the amount of information in the data used for specifying an implicit prior. The remaining fraction is used for testing the informative hypotheses. We discuss different choices of this parameter and present a scheme for setting it. Furthermore, a software package is described which computes the approximated adjusted fractional Bayes factor. Using this software package, psychological researchers can evaluate informative hypotheses by means of Bayes factors in an easy manner. Two empirical examples are used to illustrate the procedure. © 2017 The British Psychological Society.
Improving the Factor Structure of Psychological Scales
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
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.
Evaluation of damping loss factor of flat laminates by sound transmission
NASA Astrophysics Data System (ADS)
Parrinello, A.; Ghiringhelli, G. L.
2018-06-01
A novel approach to investigate and evaluate the damping loss factor of a planar multilayered structure is presented. A statistical analysis reveals the connection between the damping properties of the structure and the transmission of sound through the thickness of its laterally infinite counterpart. The obtained expression for the panel loss factor involves all the derivatives of the transmission and reflection coefficients of the layered structure with respect each layer damping. The properties of the fluid for which the sound transmission is evaluated are chosen to fulfil the hypotheses on the basis of the statistical formulation. A transfer matrix approach is used to compute the required transmission and reflection coefficients, making it possible to deal with structures having arbitrary stratifications of different layers and also granting high efficiency in a wide frequency range. Comparison with alternative formulations and measurements demonstrates the effectiveness of the proposed methodology.
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
The relationship between cost estimates reliability and BIM adoption: SEM analysis
NASA Astrophysics Data System (ADS)
Ismail, N. A. A.; Idris, N. H.; Ramli, H.; Rooshdi, R. R. Raja Muhammad; Sahamir, S. R.
2018-02-01
This paper presents the usage of Structural Equation Modelling (SEM) approach in analysing the effects of Building Information Modelling (BIM) technology adoption in improving the reliability of cost estimates. Based on the questionnaire survey results, SEM analysis using SPSS-AMOS application examined the relationships between BIM-improved information and cost estimates reliability factors, leading to BIM technology adoption. Six hypotheses were established prior to SEM analysis employing two types of SEM models, namely the Confirmatory Factor Analysis (CFA) model and full structural model. The SEM models were then validated through the assessment on their uni-dimensionality, validity, reliability, and fitness index, in line with the hypotheses tested. The final SEM model fit measures are: P-value=0.000, RMSEA=0.079<0.08, GFI=0.824, CFI=0.962>0.90, TLI=0.956>0.90, NFI=0.935>0.90 and ChiSq/df=2.259; indicating that the overall index values achieved the required level of model fitness. The model supports all the hypotheses evaluated, confirming that all relationship exists amongst the constructs are positive and significant. Ultimately, the analysis verified that most of the respondents foresee better understanding of project input information through BIM visualization, its reliable database and coordinated data, in developing more reliable cost estimates. They also perceive to accelerate their cost estimating task through BIM adoption.
2016-10-21
grafting density is a key factor in the design of self - healing composite materials. There were two hypotheses that might help explain how the grafting...its physical properties. Herein we report several mechanisms by which autonomic material self -protection may be real ized. The incorporation of...network rapidly forms an endoskeletal structure within a flexible rubber , stiffening it up to 18x. Polymer seed particles have also been developed
Topa Cantisano, Gabriela; Morales Domínguez, J F; Depolo, Marco
2008-05-01
Although sexual harassment has been extensively studied, empirical research has not led to firm conclusions about its antecedents and consequences, both at the personal and organizational level. An extensive literature search yielded 42 empirical studies with 60 samples. The matrix correlation obtained through meta-analytic techniques was used to test a structural equation model. Results supported the hypotheses regarding organizational environmental factors as main predictors of harassment.
Transfer factor - hypotheses for its structure and function.
Shifrine, M; Scibienski, R
1975-01-01
Transfer factor (TF) is a dialyzable extract from primed lymphocytes that is able to transfer specific delayed hypersensitivity from one animal to another. On the basis of available data we suggest that TF is a polypeptide with a molecular weight below 15,000 daltons. We hypothesize that TF is the variable light or heavy chain domain of immunoglobulin: such a molecule conforms with the accepted properties of TF and also has the necessary specificity requirements. We also hypothesize that TF is part of a receptor site. beta-2-microglobulin, a molecule that is an integral part of cell surfaces, could be the anchor for TF. beta-2-microglobulin has homologies with the constant portion of immunoglobulin light or heavy chain and thus would combine with the variable domain (TF) to form a complete receptor site for a specific antigen. The properties of TF suggest its mode of action, which is discussed in detail in the text. The biologic advantages of TF is its ability to confer immediate (immunologie specific) protection while the 'normal' immune response develops.
Doyle, David Matthew; Molix, Lisa
2015-01-01
Work on structural stigma shows how public policy affects health outcomes for members of devalued groups, including sexual minorities. In the current research, structural stigma is proposed as a moderating variable that strengthens deleterious associations between perceived discrimination and social relationship functioning. Hypotheses were tested in two cross-sectional studies, including both online (N = 214; Study 1) and community (N = 94; Study 2) samples of sexual minority men and women residing throughout the United States. Structural stigma was coded from policy related to sexual minority rights within each state. Confirming hypotheses, support for the moderating role of structural stigma was found via multilevel models across studies. Specifically, associations between perceived discrimination and friendship strain, loneliness (Study 1) and familial strain (Study 2) were increased for those who resided in states with greater levels of structural stigma and attenuated for those who resided in states with lesser levels. In Study 1, these results were robust to state-level covariates (conservatism and religiosity), but conservatism emerged as a significant moderator in lieu of structural stigma in Study 2. Results are discussed in the context of the shifting landscape of public policy related to sexual minority rights within the United States. PMID:26807046
Longitudinal Stability of the Leadership Scale for Sports
ERIC Educational Resources Information Center
Fletcher, Richard B.; Roberts, Margaret H.
2013-01-01
This study evaluated the invariance properties of the Leadership Scale for Sport in a sample of 219 female netball players over four time points within a 10-week playing season. Support was found for Chelladurai and Saleh's (1980) hypothesized 5-factor structure of the Leadership Scale for Sport. Furthermore, differential stability and partial…
The Factor Structure of Concrete and Formal Operations: A Confirmation of Piaget.
ERIC Educational Resources Information Center
Gray, William M.
Piaget has hypothesized that concrete and formal operations can be described by specific logical models. The present study focused on assessing various aspects of four concrete operational groupings and two variations of two formal operational characteristics. Six hundred twenty-two 9-14 year old students participating in the Human Sciences…
Intimate Homicide between Asians and Non-Asians: The Impact of Community Context
ERIC Educational Resources Information Center
Wu, Bohsiu
2009-01-01
This study tests two competing hypotheses regarding the social structural dynamics of intimate homicide: backlash versus collective efficacy. This study also examines the role of race in how social factors specified in each hypothesis affect intimate homicide. Data are from the California Vital Statistics and Homicide Data, 1990-1999. Results from…
Modifiable Prostate Cancer Risk Reduction and Early Detection Behaviors in Black Men
ERIC Educational Resources Information Center
Odedina, Folakemi T.; Scrivens, John J., Jr.; Larose-Pierre, Margareth; Emanuel, Frank; Adams, Angela Denise; Dagne, Getachew A.; Pressey, Shannon Alexis; Odedina, Oladapo
2011-01-01
Objective: To explore the personal factors related to modifiable prostate cancer risk-reduction and detection behaviors among black men. Methods: Three thousand four hundred thirty (3430) black men were surveyed and structural equation modeling employed to test study hypotheses. Results: Modifiable prostate cancer risk-reduction behavior was found…
Bayes Factor Covariance Testing in Item Response Models.
Fox, Jean-Paul; Mulder, Joris; Sinharay, Sandip
2017-12-01
Two marginal one-parameter item response theory models are introduced, by integrating out the latent variable or random item parameter. It is shown that both marginal response models are multivariate (probit) models with a compound symmetry covariance structure. Several common hypotheses concerning the underlying covariance structure are evaluated using (fractional) Bayes factor tests. The support for a unidimensional factor (i.e., assumption of local independence) and differential item functioning are evaluated by testing the covariance components. The posterior distribution of common covariance components is obtained in closed form by transforming latent responses with an orthogonal (Helmert) matrix. This posterior distribution is defined as a shifted-inverse-gamma, thereby introducing a default prior and a balanced prior distribution. Based on that, an MCMC algorithm is described to estimate all model parameters and to compute (fractional) Bayes factor tests. Simulation studies are used to show that the (fractional) Bayes factor tests have good properties for testing the underlying covariance structure of binary response data. The method is illustrated with two real data studies.
Individual differences in processing styles: validity of the Rational-Experiential Inventory.
Björklund, Fredrik; Bäckström, Martin
2008-10-01
In Study 1 (N= 203) the factor structure of a Swedish translation of Pacini and Epstein's Rational-Experiential Inventory (REI-40) was investigated using confirmatory factor analysis. The hypothesized model with rationality and experientiality as orthogonal factors had satisfactory fit to the data, significantly better than alternative models (with two correlated factors or a single factor). Inclusion of "ability" and "favorability" subscales for rationality and experientiality increased fit further. It was concluded that the structural validity of the REI is adequate. In Study 2 (N= 72) the REI-factors were shown to have theoretically meaningful correlations to other personality traits, indicating convergent and discriminant validity. Finally, scores on the rationality scale were negatively related to risky choice framing effects in Kahneman and Tversky's Asian disease task, indicating concurrent validity. On the basis of these findings it was concluded that the test has satisfactory psychometric properties.
Barbeau, Myriam A.
2016-01-01
Top-down, bottom-up, middle-out and abiotic factors are usually viewed as main forces structuring biological communities, although assessment of their relative importance, in a single study, is rarely done. We quantified, using multivariate methods, associations between abiotic and biotic (top-down, bottom-up and middle-out) variables and infaunal population/community variation on intertidal mudflats in the Bay of Fundy, Canada, over two years. Our analysis indicated that spatial structural factors like site and plot accounted for most of the community and population variation. Although we observed a significant relationship between the community/populations and the biotic and abiotic variables, most were of minor importance relative to the structural factors. We suggest that community and population structure were relatively uncoupled from the structuring influences of biotic and abiotic factors in this system because of high concentrations of resources that sustain high densities of infauna and limit exploitative competition. Furthermore, we hypothesize that the infaunal community primarily reflects stochastic spatial events, namely a “first come, first served” process. PMID:26790098
Ocean plankton. Determinants of community structure in the global plankton interactome.
Lima-Mendez, Gipsi; Faust, Karoline; Henry, Nicolas; Decelle, Johan; Colin, Sébastien; Carcillo, Fabrizio; Chaffron, Samuel; Ignacio-Espinosa, J Cesar; Roux, Simon; Vincent, Flora; Bittner, Lucie; Darzi, Youssef; Wang, Jun; Audic, Stéphane; Berline, Léo; Bontempi, Gianluca; Cabello, Ana M; Coppola, Laurent; Cornejo-Castillo, Francisco M; d'Ovidio, Francesco; De Meester, Luc; Ferrera, Isabel; Garet-Delmas, Marie-José; Guidi, Lionel; Lara, Elena; Pesant, Stéphane; Royo-Llonch, Marta; Salazar, Guillem; Sánchez, Pablo; Sebastian, Marta; Souffreau, Caroline; Dimier, Céline; Picheral, Marc; Searson, Sarah; Kandels-Lewis, Stefanie; Gorsky, Gabriel; Not, Fabrice; Ogata, Hiroyuki; Speich, Sabrina; Stemmann, Lars; Weissenbach, Jean; Wincker, Patrick; Acinas, Silvia G; Sunagawa, Shinichi; Bork, Peer; Sullivan, Matthew B; Karsenti, Eric; Bowler, Chris; de Vargas, Colomban; Raes, Jeroen
2015-05-22
Species interaction networks are shaped by abiotic and biotic factors. Here, as part of the Tara Oceans project, we studied the photic zone interactome using environmental factors and organismal abundance profiles and found that environmental factors are incomplete predictors of community structure. We found associations across plankton functional types and phylogenetic groups to be nonrandomly distributed on the network and driven by both local and global patterns. We identified interactions among grazers, primary producers, viruses, and (mainly parasitic) symbionts and validated network-generated hypotheses using microscopy to confirm symbiotic relationships. We have thus provided a resource to support further research on ocean food webs and integrating biological components into ocean models. Copyright © 2015, American Association for the Advancement of Science.
Huang, Francis L; Cornell, Dewey G; Konold, Timothy; Meyer, Joseph P; Lacey, Anna; Nekvasil, Erin K; Heilbrun, Anna; Shukla, Kathan D
2015-12-01
School climate is well recognized as an important influence on student behavior and adjustment to school, but there is a need for theory-guided measures that make use of teacher perspectives. Authoritative school climate theory hypothesizes that a positive school climate is characterized by high levels of disciplinary structure and student support. A teacher version of the Authoritative School Climate Survey (ASCS) was administered to a statewide sample of 9099 7th- and 8th-grade teachers from 366 schools. The study used exploratory and multilevel confirmatory factor analyses (MCFA) that accounted for the nested data structure and allowed for the modeling of the factor structures at 2 levels. Multilevel confirmatory factor analyses conducted on both an exploratory (N = 4422) and a confirmatory sample (N = 4677) showed good support for the factor structures investigated. Factor correlations at 2 levels indicated that schools with greater levels of disciplinary structure and student support had higher student engagement, less teasing and bullying, and lower student aggression toward teachers. The teacher version of the ASCS can be used to assess 2 key domains of school climate and associated measures of student engagement and aggression toward peers and teachers. © 2015, American School Health Association.
Sandoval, Guillermo A; Brown, Adalsteinn D; Wodchis, Walter P; Anderson, Geoffrey M
2018-05-17
Measuring the value of medical imaging is challenging, in part, due to the lack of conceptual frameworks underlying potential mechanisms where value may be assessed. To address this gap, this article proposes a framework that builds on the large body of literature on quality of hospital care and the classic structure-process-outcome paradigm. The framework was also informed by the literature on adoption of technological innovations and introduces 2 distinct though related aspects of imaging technology not previously addressed specifically in the literature on quality of hospital care: adoption (a structural hospital characteristic) and use (an attribute of the process of care). The framework hypothesizes a 2-part causality where adoption is proposed to be a central, linking factor between hospital structural characteristics, market factors, and hospital outcomes (ie, quality and efficiency). The first part indicates that hospital structural characteristics and market factors influence or facilitate the adoption of high technology medical imaging within an institution. The presence of this technology, in turn, is hypothesized to improve the ability of the hospital to deliver high quality and efficient care. The second part describes this ability throughout 3 main mechanisms pointing to the importance of imaging use on patients, to the presence of staff and qualified care providers, and to some elements of organizational capacity capturing an enhanced clinical environment. The framework has the potential to assist empirical investigations of the value of adoption and use of medical imaging, and to advance understanding of the mechanisms that produce quality and efficiency in hospitals. Copyright © 2018 John Wiley & Sons, Ltd.
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.
Patterns of distribution, abundance, and change over time in a subarctic marine bird community
NASA Astrophysics Data System (ADS)
Cushing, Daniel A.; Roby, Daniel D.; Irons, David B.
2018-01-01
Over recent decades, marine ecosystems of Prince William Sound (PWS), Alaska, have experienced concurrent effects of natural and anthropogenic perturbations, including variability in the climate system of the northeastern Pacific Ocean. We documented spatial and temporal patterns of variability in the summer marine bird community in relation to habitat and climate variability using boat-based surveys of marine birds conducted during the period 1989-2012. We hypothesized that a major factor structuring marine bird communities in PWS would be proximity to the shoreline, which is theorized to relate to aspects of food web structure. We also hypothesized that shifts in physical ecosystem drivers differentially affected nearshore-benthic and pelagic components of PWS food webs. We evaluated support for our hypotheses using an approach centered on community-level patterns of spatial and temporal variability. We found that an environmental gradient related to water depth and distance from shore was the dominant factor spatially structuring the marine bird community. Responses of marine birds to this onshore-offshore environmental gradient were related to dietary specialization, and separated marine bird taxa by prey type. The primary form of temporal variability over the study period was monotonic increases or decreases in abundance for 11 of 18 evaluated genera of marine birds; 8 genera had declined, whereas 3 had increased. The greatest declines occurred in genera associated with habitats that were deeper and farther from shore. Furthermore, most of the genera that declined primarily fed on pelagic prey resources, such as forage fish and mesozooplankton, and few were directly affected by the 1989 Exxon Valdez oil spill. Our observations of synchronous declines are indicative of a shift in pelagic components of PWS food webs. This pattern was correlated with climate variability at time-scales of several years to a decade.
Patterns of distribution, abundance, and change over time in a subarctic marine bird community
Cushing, Daniel; Roby, Daniel D.; Irons, David B.
2017-01-01
Over recent decades, marine ecosystems of Prince William Sound (PWS), Alaska, have experienced concurrent effects of natural and anthropogenic perturbations, including variability in the climate system of the northeastern Pacific Ocean. We documented spatial and temporal patterns of variability in the summer marine bird community in relation to habitat and climate variability using boat-based surveys of marine birds conducted during the period 1989–2012. We hypothesized that a major factor structuring marine bird communities in PWS would be proximity to the shoreline, which is theorized to relate to aspects of food web structure. We also hypothesized that shifts in physical ecosystem drivers differentially affected nearshore-benthic and pelagic components of PWS food webs. We evaluated support for our hypotheses using an approach centered on community-level patterns of spatial and temporal variability. We found that an environmental gradient related to water depth and distance from shore was the dominant factor spatially structuring the marine bird community. Responses of marine birds to this onshore-offshore environmental gradient were related to dietary specialization, and separated marine bird taxa by prey type. The primary form of temporal variability over the study period was monotonic increases or decreases in abundance for 11 of 18 evaluated genera of marine birds; 8 genera had declined, whereas 3 had increased. The greatest declines occurred in genera associated with habitats that were deeper and farther from shore. Furthermore, most of the genera that declined primarily fed on pelagic prey resources, such as forage fish and mesozooplankton, and few were directly affected by the 1989 Exxon Valdez oil spill. Our observations of synchronous declines are indicative of a shift in pelagic components of PWS food webs. This pattern was correlated with climate variability at time-scales of several years to a decade.
ERIC Educational Resources Information Center
Chen, Yu; Starobin, Soko S.
2018-01-01
This study examined a psychosocial mechanism of how general self-efficacy interacts with other key factors and influences degree aspiration for students enrolled in an urban diverse community college. Using general self-efficacy scales, the authors hypothesized the General Self-efficacy model for Community College students (the GSE-CC model). A…
A General Structure for Legal Arguments about Evidence Using Bayesian Networks
ERIC Educational Resources Information Center
Fenton, Norman; Neil, Martin; Lagnado, David A.
2013-01-01
A Bayesian network (BN) is a graphical model of uncertainty that is especially well suited to legal arguments. It enables us to visualize and model dependencies between different hypotheses and pieces of evidence and to calculate the revised probability beliefs about all uncertain factors when any piece of new evidence is presented. Although BNs…
ERIC Educational Resources Information Center
Bartning, Inge; Lundell, Fanny Forsberg; Hancock, Victorine
2012-01-01
The purpose of this article is to offer contextual linguistic explanations for morphosyntactic deviances (MSDs) in high-level second language (L2) French (30 nonnative speakers vs. 10 native speakers). It is hypothesized that the distribution of formulaic sequences (FSs) and the complexity of information structure will influence the occurrence of…
The SRP-II as a Rich Source of Data on the Psychopathic Personality
ERIC Educational Resources Information Center
Lester, Whitney S.; Salekin, Randall T.; Sellbom, Martin
2013-01-01
This study examined the factor structure, external correlates, and predictive utility of the Self-Report Psychopathy scale (SRP-II; Hare, Harpur, & Hemphill, 1989). Despite a revision of the SRP-II to address, among other criticisms, a lack of items reflecting antisocial behavior, we hypothesized that the SRP-II would have a conceptually coherent…
Community Organizations and Sense of Community: Further Development in Theory and Measurement
ERIC Educational Resources Information Center
Peterson, N. Andrew; Speer, Paul W.; Hughey, Joseph; Armstead, Theresa L.; Schneider, John E.; Sheffer, Megan A.
2008-01-01
The Community Organization Sense of Community Scale (COSOC) is a frequently used or cited measure of the construct in community psychology and other disciplines, despite a lack of confirmation of its underlying 4-factor framework. Two studies were conducted to test the hypothesized structure of the COSOC, the potential effects of method bias on…
USDA-ARS?s Scientific Manuscript database
The correct identification of the source population of an invasive species is a prerequisite for defining and testing different hypotheses concerning the environmental and evolutionary factors responsible for biological invasions. The native area of invasive species may be large, barely known and/or...
Leadership Profile of a Successful Military Middle Manager.
1979-12-01
Curriculum (consideration) HS 7 HC 7 H0 Ust2- s PS E C t 1UCE 26 H. Concerning birth order, the hypotheses are: HS 8: First born (fb) children would...it to say that first-born children are significantly less structured than their siblings as measured by the instrument used in this study. B. REMARKS...counterparts on two very important dimensions of leadership: consideration and structure. And, whether any key background factors impact on the levels of 0 DOI
Donovan, M A; Drasgow, F; Munson, L J
1998-10-01
The Perceptions of Fair Interpersonal Treatment (PFIT) scale was designed to assess employees' perceptions of the interpersonal treatment in their work environment. Analyses of the factor structure and reliability of this new instrument indicate that the PFIT scale is a reliable instrument composed of 2 factors: supervisor treatment and coworker treatment. It was hypothesized that the PFIT scale would be positively correlated with job satisfaction variables and negatively correlated with work withdrawal, job withdrawal, experiences of sexual harassment, and an organization's tolerance of sexual harassment. Results based on 509 employees in a private-sector organization and 217 female faculty and staff members at a large midwestern university supported these hypotheses. Arguments that common method variance and employees' dispositions are responsible for the significant correlations between the PFIT scale and other job-related variables were eliminated. The implications of these results are discussed.
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.
de Vries, Janneke E; Dekker, Carolien; Bastiaenen, Carolien H G; Goossens, Mariëlle E J B; Engelbert, Raoul H H; Verbunt, Jeanine A M C F
2017-11-29
To assess the factor structure, related constructs and internal consistency of the Child Activity Limitation Interview 21-Child version for use in Dutch-language countries. Cross-sectional validation study: After forward and back translation of the Dutch version of the Child Activity Limitation Interview 21-Child adolescents (11-21 years old) with chronic musculoskeletal pain completed an assessment. The assessment contained the Dutch Child Activity Limitation Interview, and questionnaires about demographics, pain intensity, functional disability, anxiety and depression. Internal consistency and construct validity were evaluated through exploratory factor analysis (principal axis factoring with oblique rotation) and hypotheses testing using pain intensity, activity limitations, anxiety and depression as comparative constructs. Seventy-four adolescents completed the assessment. Exploratory factor analysis resulted in a two-factor structure, explaining 50% of the variance. Internal consistency was good (Cronbach's α = 0.91 total scale, α = 0.90 Factor 1, α = 0.80 Factor 2). All nine hypotheses were confirmed. The Dutch version can be used to assess pain-related disability in Dutch-speaking adolescents comparable to the study sample. Scores on both subscales provide insight into the severity of the pain-related disability in both daily routine and more physically vigorous activities. Implications for Rehabilitation Chronic pain is a disabling disorder which not only impacts physically but restricts quality of life. This study provides clinicians a questionnaire to measure pain-related disability and quantify the impact of pain on the daily living of adolescents. The advantage of the Dutch version of the Child Activity and Limitations Interview over other measurements is that it can distinguish limitations in daily activities from more physically vigorous activities.
The factorial validity of the Maslach Burnout Inventory-Student Survey in China.
Hu, Qiao; Schaufeli, Wilmar B
2009-10-01
The dimensional structure of the Maslach Burnout Inventory-Student Survey (MBI-SS) was investigated using data collected from three samples of Chinese students in two high schools, a university, and a nursing school, respectively (total N = 1,499; 36% males, 64% females; M age 19.0 yr., SD = 1.3). Single group Confirmatory Factor Analyses corroborated the hypothesized three-factor model for the composite sample as well as for the three independent samples. Subsequent multigroup analyses revealed that the three-dimensional structure of the MBI-SS is partially invariant across three samples. It is concluded that the MBI-SS can be used to assess burnout in Chinese students.
A phenotypic structure and neural correlates of compulsive behaviors in adolescents.
Montigny, Chantale; Castellanos-Ryan, Natalie; Whelan, Robert; Banaschewski, Tobias; Barker, Gareth J; Büchel, Christian; Gallinat, Jürgen; Flor, Herta; Mann, Karl; Paillère-Martinot, Marie-Laure; Nees, Frauke; Lathrop, Mark; Loth, Eva; Paus, Tomas; Pausova, Zdenka; Rietschel, Marcella; Schumann, Gunter; Smolka, Michael N; Struve, Maren; Robbins, Trevor W; Garavan, Hugh; Conrod, Patricia J
2013-01-01
A compulsivity spectrum has been hypothesized to exist across Obsessive-Compulsive disorder (OCD), Eating Disorders (ED), substance abuse (SA) and binge-drinking (BD). The objective was to examine the validity of this compulsivity spectrum, and differentiate it from an externalizing behaviors dimension, but also to look at hypothesized personality and neural correlates. A community-sample of adolescents (N=1938; mean age 14.5 years), and their parents were recruited via high-schools in 8 European study sites. Data on adolescents' psychiatric symptoms, DSM diagnoses (DAWBA) and substance use behaviors (AUDIT and ESPAD) were collected through adolescent- and parent-reported questionnaires and interviews. The phenotypic structure of compulsive behaviors was then tested using structural equation modeling. The model was validated using personality variables (NEO-FFI and TCI), and Voxel-Based Morphometry (VBM) analysis. Compulsivity symptoms best fit a higher-order two factor model, with ED and OCD loading onto a compulsivity factor, and BD and SA loading onto an externalizing factor, composed also of ADHD and conduct disorder symptoms. The compulsivity construct correlated with neuroticism (r=0.638; p ≤ 0.001), conscientiousness (r=0.171; p ≤ 0.001), and brain gray matter volume in left and right orbitofrontal cortex, right ventral striatum and right dorsolateral prefrontal cortex. The externalizing factor correlated with extraversion (r=0.201; p ≤ 0.001), novelty-seeking (r=0.451; p ≤ 0.001), and negatively with gray matter volume in the left inferior and middle frontal gyri. Results suggest that a compulsivity spectrum exists in an adolescent, preclinical sample and accounts for variance in both OCD and ED, but not substance-related behaviors, and can be differentiated from an externalizing spectrum.
Development and preliminary validation of the Parenting around SNAcking Questionnaire (P-SNAQ).
Davison, K K; Blake, C E; Kachurak, A; Lumeng, J C; Coffman, D L; Miller, A L; Hughes, S O; Power, T G; Vaughn, A F; Blaine, R E; Younginer, N; Fisher, J O
2018-06-01
Snacking makes significant contributions to children's dietary intake but is poorly understood from a parenting perspective. This research was designed to develop and evaluate the psychometrics of a theoretically grounded, empirically-informed measure of snack parenting. The Parenting around SNAcking Questionnaire (P-SNAQ) was developed using a conceptual model derived from current theory and mixed-methods research to include 20 hypothesized snack parenting practices along 4 parenting dimensions (autonomy support, structure, coercive control and permissiveness). Expert panel evaluation and cognitive interviews were used to refine items and construct definitions. The initial instrument of 105 items was administered to an ethnically diverse, low-income sample of 305 parents (92% mothers) of children aged 1-6 y participating in three existing cohort studies. The sample was randomly split into two equal samples. Exploratory factor analysis was conducted with the first sample to identify snack parenting practices within each parenting dimension, followed by confirmatory factor analysis with the second sample to test the hypothesized factor structure. Internal consistency of sub-scales and associations with existing measures of food parenting practices and styles and child weight status were evaluated. The final P-SNAQ scale included 51 items reflecting 14 snack parenting practices across four parenting dimensions. The factor structure of the P-SNAQ was consistent with prior theoretical frameworks. Internal consistency coefficients were good to very good for 12 out of 14 scales and subscale scores were moderately correlated with previously validated measures. In conclusion, initial evidence suggests that P-SNAQ is a psychometrically sound measure for evaluating a wide range of snack parenting practices in young children. Copyright © 2018 Elsevier Ltd. All rights reserved.
A Phenotypic Structure and Neural Correlates of Compulsive Behaviors in Adolescents
Montigny, Chantale; Castellanos-Ryan, Natalie; Whelan, Robert; Banaschewski, Tobias; Barker, Gareth J.; Büchel, Christian; Gallinat, Jürgen; Flor, Herta; Mann, Karl; Paillère-Martinot, Marie-Laure; Nees, Frauke; Lathrop, Mark; Loth, Eva; Paus, Tomas; Pausova, Zdenka; Rietschel, Marcella; Schumann, Gunter; Smolka, Michael N.; Struve, Maren; Robbins, Trevor W.; Garavan, Hugh; Conrod, Patricia J.
2013-01-01
Background A compulsivity spectrum has been hypothesized to exist across Obsessive-Compulsive disorder (OCD), Eating Disorders (ED), substance abuse (SA) and binge-drinking (BD). The objective was to examine the validity of this compulsivity spectrum, and differentiate it from an externalizing behaviors dimension, but also to look at hypothesized personality and neural correlates. Method A community-sample of adolescents (N=1938; mean age 14.5 years), and their parents were recruited via high-schools in 8 European study sites. Data on adolescents’ psychiatric symptoms, DSM diagnoses (DAWBA) and substance use behaviors (AUDIT and ESPAD) were collected through adolescent- and parent-reported questionnaires and interviews. The phenotypic structure of compulsive behaviors was then tested using structural equation modeling. The model was validated using personality variables (NEO-FFI and TCI), and Voxel-Based Morphometry (VBM) analysis. Results Compulsivity symptoms best fit a higher-order two factor model, with ED and OCD loading onto a compulsivity factor, and BD and SA loading onto an externalizing factor, composed also of ADHD and conduct disorder symptoms. The compulsivity construct correlated with neuroticism (r=0.638; p≤0.001), conscientiousness (r=0.171; p≤0.001), and brain gray matter volume in left and right orbitofrontal cortex, right ventral striatum and right dorsolateral prefrontal cortex. The externalizing factor correlated with extraversion (r=0.201; p≤0.001), novelty-seeking (r=0.451; p≤0.001), and negatively with gray matter volume in the left inferior and middle frontal gyri. Conclusions Results suggest that a compulsivity spectrum exists in an adolescent, preclinical sample and accounts for variance in both OCD and ED, but not substance-related behaviors, and can be differentiated from an externalizing spectrum. PMID:24244633
ERIC Educational Resources Information Center
Herman, Keith C.; Lambert, Sharon F.; Reinke, Wendy M.; Ialongo, Nicholas S.
2008-01-01
The present study investigated the role of low academic competence in the emergence of depressive cognitions and symptoms. Structural equation modeling was conducted on a longitudinal sample of African American boys (n = 253) and girls (n = 221). Results supported the hypothesized path models from academic competence in 1st grade to depressive…
Maureen C. Kennedy; E. David Ford; Thomas M. Hinckley
2009-01-01
Many hypotheses have been advanced about factors that control tree longevity. We use a simulation model with multi-criteria optimization and Pareto optimality to determine branch morphologies in the Pinaceae that minimize the effect of growth limitations due to water stress while simultaneously maximizing carbohydrate gain. Two distinct branch morphologies in the...
Validating the Riverside Acculturation Stress Inventory with Asian Americans.
Miller, Matthew J; Kim, Jungeun; Benet-Martínez, Verónica
2011-06-01
An emerging body of empirical research highlights the impact of acculturative stress in the lives of culturally diverse populations. Therefore, to facilitate future research in this area, we conducted 3 studies to examine the psychometric properties of the Riverside Acculturation Stress Inventory (RASI; Benet-Martínez & Haritatos, 2005) and its 5 subscales in a total sample of 793 self-identified Asian American participants. The reliability and validity of RASI scores and the hypothesized 1-factor higher order model (with 1st-order factors Language Skills, Work Challenges, Intercultural Relations, Discrimination, and Cultural Isolation) of the RASI were examined in Study 1. The RASI higher order structure and score validity and reliability were examined across different generational groups in Study 2. The stability of RASI scores over a 3-week period was examined in Study 3. Overall, findings from these studies support the hypothesized structure of the RASI and indicate that this brief instrument provides reliable and valid acculturative stress scores. In addition, results suggest that RASI items are interpreted in an equivalent manner across different generations of Asian American individuals. Implications for research and assessment are discussed. 2011 APA, all rights reserved
The Economic Effect of Competition in the Air Transportation Industry
NASA Technical Reports Server (NTRS)
Hubbard, H. B.
1972-01-01
The air transportation industry has been described as a highly-competitive, regulated oligopoly or as a price-regulated cartel with blocked entry, resulting in excessive service and low load factors. The current structure of the industry has been strongly influenced by the hypotheses that increased levels of competition are desirable per se, and that more competing carriers can be economically supported in larger markets, in longer haul markets, with lower unit costs, and with higher fare levels. An elementary application of competition/game theory casts doubt on the validity of these hypotheses, but rather emphasizes the critical importance of the short-term non-variable costs in determining economic levels of competition.
Factor Structure of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA)
Díaz-Santos, Mirella; Cumba-Avilés, Eduardo; Bernal, Guillermo; Rivera-Medina, Carmen
2018-01-01
The current concept and measures of self-efficacy for depression in adolescents do not consider developmental and cultural aspects essential to understand and assess this construct in Latino youth. We examined the factor structure of the Escala de Autoeficacia para la Depresión en Adolescentes (EADA): a Spanish instrument designed to assess this construct as experienced by this population. Participants were 116 Puerto Rican adolescents aged 13 to 17 years who completed the EADA and two other self-report measures. An exploratory factor analysis yielded a two-factor solution (Personal Self-Efficacy for Depression and Interpersonal Self-Efficacy for Depression) accounting for 37.57% of the total variance. Results revealed that EADA factors have excellent internal consistency as well as concurrent and construct validity, supporting its adequacy to assess Latino adolescents’ self-efficacy for depression. The conceptual meaning of the factors was consistent with the distinction between aspects of this construct hypothesized to be important among Latino youth.
Babcock, Russell C.; Dambacher, Jeffrey M.; Morello, Elisabetta B.; Plagányi, Éva E.; Hayes, Keith R.; Sweatman, Hugh P. A.; Pratchett, Morgan S.
2016-01-01
The crown-of-thorns starfish Acanthaster planci (COTS) has contributed greatly to declines in coral cover on Australia’s Great Barrier Reef, and remains one of the major acute disturbances on Indo-Pacific coral reefs. Despite uncertainty about the underlying causes of outbreaks and the management responses that might address them, few studies have critically and directly compared competing hypotheses. This study uses qualitative modelling to compare hypotheses relating to outbreak initiation, explicitly considering the potential role of positive feedbacks, elevated nutrients, and removal of starfish predators by fishing. When nutrients and fishing are considered in isolation, the models indicate that a range of alternative hypotheses are capable of explaining outbreak initiation with similar levels of certainty. The models also suggest that outbreaks may be caused by multiple factors operating simultaneously, rather than by single proximal causes. As the complexity and realism of the models increased, the certainty of outcomes decreased, but key areas that require further research to improve the structure of the models were identified. Nutrient additions were likely to result in outbreaks only when COTS larvae alone benefitted from nutrients. Similarly, the effects of fishing on the decline of corals depended on the complexity of interactions among several categories of fishes. Our work suggests that management approaches which seek to be robust to model structure uncertainty should allow for multiple potential causes of outbreaks. Monitoring programs can provide tests of alternative potential causes of outbreaks if they specifically monitor all key taxa at reefs that are exposed to appropriate combinations of potential causal factors. PMID:28036360
From Racial Discrimination to Risky Sex: Prospective Relations Involving Peers and Parents
Roberts, Megan E.; Gibbons, Frederick X.; Gerrard, Meg; Weng, Chih-Yuan; Murry, Velma M.; Simons, Leslie G.; Simons, Ronald L.; Lorenz, Frederick O.
2013-01-01
This study investigated how early experience with racial discrimination affected the subsequent risky sexual behaviors of a diverse sample of African American youths (N = 745). The analyses focused on 3 risk-promoting factors thought to mediate the hypothesized discrimination → risky sex relation: negative affect, affiliation with deviant peers, and favorable attitudes toward risky sex. In addition, attentive parenting was examined as a protective factor. Analyses using structural equation modeling revealed that youths who perceived more racial discrimination at age 10 or 11 were engaging in more sexual risk taking at age 18 or 19. This relation was mediated by the hypothesized risk-promoting factors via pathways that were consistent with our conceptual model. Results also indicated a prospective reciprocal relation between parenting and children’s deviant affiliations: deviant peer affiliations at age 10 or 11 predicted more attentive parenting behaviors by the parents; this response from the parents, in turn, predicted relatively fewer deviant affiliations when the youths were 15 or 16. Study findings are discussed in terms of their relevance to the disproportionately high rates of sexually transmitted infections among African Americans. PMID:21942666
Fernández, Maria E.; Diamond, Pamela M.; Rakowski, William; Gonzales, Alicia; Tortolero-Luna, Guillermo; Williams, Janet; Morales-Campos, Daisy Y.
2011-01-01
While self-efficacy (SE), a construct from Social Cognitive Theory, has been shown to influence other screening behaviors, few measures currently exist for measuring Pap test SE. This paper describes the development and psychometric testing of such a measure for Mexican-American women. Data from two separate samples of Mexican-American women 50 years or older, obtained as part of a study to develop and evaluate a breast and cervical cancer screening educational program, were used in the current study. Exploratory factor analysis indicated a single factor solution and all item loadings were > .73. Confirmatory analysis confirmed a single factor structure with all standardized loadings greater than .40 as hypothesized. The eight item SE scale demonstrated high internal consistency (Cronbach's alpha = .95). As hypothesized, SE was correlated with knowledge, prior experience, and screening intention. Logistic regression supported the theoretical relationship that women with higher SE were more likely to have had a recent Pap test. Findings showed a significant increase in SE following the intervention, indicating the measure has good sensitivity to change over time. PMID:19258484
Scale Development for Measuring and Predicting Adolescents’ Leisure Time Physical Activity Behavior
Ries, Francis; Romero Granados, Santiago; Arribas Galarraga, Silvia
2009-01-01
The aim of this study was to develop a scale for assessing and predicting adolescents’ physical activity behavior in Spain and Luxembourg using the Theory of Planned Behavior as a framework. The sample was comprised of 613 Spanish (boys = 309, girls = 304; M age =15.28, SD =1.127) and 752 Luxembourgish adolescents (boys = 343, girls = 409; M age = 14.92, SD = 1.198), selected from students of two secondary schools in both countries, with a similar socio-economic status. The initial 43-items were all scored on a 4-point response format using the structured alternative format and translated into Spanish, French and German. In order to ensure the accuracy of the translation, standardized parallel back-translation techniques were employed. Following two pilot tests and subsequent revisions, a second order exploratory factor analysis with oblimin direct rotation was used for factor extraction. Internal consistency and test-retest reliabilities were also tested. The 4-week test-retest correlations confirmed the items’ time stability. The same five factors were obtained, explaining 63.76% and 63.64% of the total variance in both samples. Internal consistency for the five factors ranged from α = 0.759 to α = 0. 949 in the Spanish sample and from α = 0.735 to α = 0.952 in the Luxembourgish sample. For both samples, inter-factor correlations were all reported significant and positive, except for Factor 5 where they were significant but negative. The high internal consistency of the subscales, the reported item test-retest reliabilities and the identical factor structure confirm the adequacy of the elaborated questionnaire for assessing the TPB-based constructs when used with a population of adolescents in Spain and Luxembourg. The results give some indication that they may have value in measuring the hypothesized TPB constructs for PA behavior in a cross-cultural context. Key points When using the structured alternative format, weak internal consistency was obtained. Rephrasing the items and scoring items on a Likert-type scale enhanced greatly the subscales reliability. Identical factorial structure was extracted for both culturally different samples. The obtained factors, namely perceived physical competence, parents’ physical activity, perceived resources support, attitude toward physical activity and perceived parental support were hypothesized as for the original TPB constructs. PMID:24149606
Scale development for measuring and predicting adolescents' leisure time physical activity behavior.
Ries, Francis; Romero Granados, Santiago; Arribas Galarraga, Silvia
2009-01-01
The aim of this study was to develop a scale for assessing and predicting adolescents' physical activity behavior in Spain and Luxembourg using the Theory of Planned Behavior as a framework. The sample was comprised of 613 Spanish (boys = 309, girls = 304; M age =15.28, SD =1.127) and 752 Luxembourgish adolescents (boys = 343, girls = 409; M age = 14.92, SD = 1.198), selected from students of two secondary schools in both countries, with a similar socio-economic status. The initial 43-items were all scored on a 4-point response format using the structured alternative format and translated into Spanish, French and German. In order to ensure the accuracy of the translation, standardized parallel back-translation techniques were employed. Following two pilot tests and subsequent revisions, a second order exploratory factor analysis with oblimin direct rotation was used for factor extraction. Internal consistency and test-retest reliabilities were also tested. The 4-week test-retest correlations confirmed the items' time stability. The same five factors were obtained, explaining 63.76% and 63.64% of the total variance in both samples. Internal consistency for the five factors ranged from α = 0.759 to α = 0. 949 in the Spanish sample and from α = 0.735 to α = 0.952 in the Luxembourgish sample. For both samples, inter-factor correlations were all reported significant and positive, except for Factor 5 where they were significant but negative. The high internal consistency of the subscales, the reported item test-retest reliabilities and the identical factor structure confirm the adequacy of the elaborated questionnaire for assessing the TPB-based constructs when used with a population of adolescents in Spain and Luxembourg. The results give some indication that they may have value in measuring the hypothesized TPB constructs for PA behavior in a cross-cultural context. Key pointsWhen using the structured alternative format, weak internal consistency was obtained. Rephrasing the items and scoring items on a Likert-type scale enhanced greatly the subscales reliability.Identical factorial structure was extracted for both culturally different samples.The obtained factors, namely perceived physical competence, parents' physical activity, perceived resources support, attitude toward physical activity and perceived parental support were hypothesized as for the original TPB constructs.
Development and validity of the Emotion and Motivation Self-regulation Questionnaire (EMSR-Q).
Alonso-Tapia, Jesús; Panadero Calderón, Ernesto; Díaz Ruiz, Miguel A
2014-07-15
This study has two objectives, first, to develop and validate the "Emotion and Motivation Self-regulation Questionnaire" (EMSR-Q), and second, to analyze (in the context of the questionnaire validation process) the relationships between self-regulation styles (SRS) rooted in goal orientations, and classroom motivational climate (CMC). A total of 664 Secondary Education students from Madrid (Spain) formed the sample of the study. It was divided randomly in two groups to perform confirmatory factor analysis and to cross-validate the results. Both analyses supported a five first-order factor structure, organized around two second-order factors, "Learning self-regulation style" (LSR) and "Avoidance self-regulation style" (ASR): (χ 2 /df = 2.71; GFI = .89; IFI = .84; CFI = .84; RMSEA = .07). Hypotheses concerning the relationships between SRS, goal orientations and expectancies are supported by additional correlation and factor analyses. Moreover, several regression analyses supported for the most part of the remaining hypotheses concerning the role of self-regulation styles as predictors of classroom motivational climate (CMC) perception, of change in self-regulation attributed to teacher work, and of students' satisfaction with this same work. Theoretical and practical implications are discussed.
Giesbrecht, Chantelle J; O'Rourke, Norm; Leonova, Olga; Strehlau, Verena; Paquet, Karine; Vila-Rodriguez, Fidel; Panenka, William J; MacEwan, G William; Smith, Geoffrey N; Thornton, Allen E; Honer, William G
2016-01-01
Rates of psychopathology are elevated in marginalized and unstably housed persons, underscoring the need for applicable clinical measures for these populations. The Positive and Negative Syndrome Scale (PANSS) is a clinical instrument principally developed for use in schizophrenia to identify the presence and severity of psychopathology symptoms. The current study investigates whether a reliable and valid PANSS factor structure emerges in a marginally housed, heterogeneous sample recruited from the Downtown Eastside of Vancouver where substance use disorders and psychiatric illness are pervasive. Participants (n = 270) underwent structured clinical assessments including the PANSS and then were randomly assigned to either exploratory (EFA) or confirmatory factor analytic (CFA) subsamples. EFA pointed to a novel three factor PANSS. This solution was supported by CFA. All retained items (28 out of 30) load significantly upon hypothesized factors and model goodness of fit analyses are in the acceptable to good range. Each of the three first-order factor constructs, labeled Psychosis/Disorganized, Negative Symptoms/Hostility, and Insight/Awareness, contributed significantly to measurement of a higher-order psychopathology construct. Further, the latent structure of this 3-factor solution appears temporally consistent over one-year. This PANSS factor structure appears valid and reliable for use in persons with multimorbidity, including substance use disorders. The structure is somewhat distinct from existing solutions likely due to the unique characteristics of this marginally housed sample.
Giesbrecht, Chantelle J.; O’Rourke, Norm; Leonova, Olga; Strehlau, Verena; Paquet, Karine; Vila-Rodriguez, Fidel; Panenka, William J.; MacEwan, G. William; Smith, Geoffrey N.; Thornton, Allen E.; Honer, William G.
2016-01-01
Rates of psychopathology are elevated in marginalized and unstably housed persons, underscoring the need for applicable clinical measures for these populations. The Positive and Negative Syndrome Scale (PANSS) is a clinical instrument principally developed for use in schizophrenia to identify the presence and severity of psychopathology symptoms. The current study investigates whether a reliable and valid PANSS factor structure emerges in a marginally housed, heterogeneous sample recruited from the Downtown Eastside of Vancouver where substance use disorders and psychiatric illness are pervasive. Participants (n = 270) underwent structured clinical assessments including the PANSS and then were randomly assigned to either exploratory (EFA) or confirmatory factor analytic (CFA) subsamples. EFA pointed to a novel three factor PANSS. This solution was supported by CFA. All retained items (28 out of 30) load significantly upon hypothesized factors and model goodness of fit analyses are in the acceptable to good range. Each of the three first-order factor constructs, labeled Psychosis/Disorganized, Negative Symptoms/Hostility, and Insight/Awareness, contributed significantly to measurement of a higher-order psychopathology construct. Further, the latent structure of this 3-factor solution appears temporally consistent over one-year. This PANSS factor structure appears valid and reliable for use in persons with multimorbidity, including substance use disorders. The structure is somewhat distinct from existing solutions likely due to the unique characteristics of this marginally housed sample. PMID:26999280
Smith, Gregory C; Palmieri, Patrick A; Hancock, Gregory R; Richardson, Rhonda A
2008-01-01
An adaptation of the Family Stress Model (FSM) with hypothesized linkages between family contextual factors, custodial grandmothers' psychological distress, parenting practices, and grandchildren's adjustment was tested with structural equation modeling. Interview data from 733 custodial grandmothers of grandchildren between ages 4-17 revealed that the effect of grandmothers' distress on grandchildren's adjustment was mediated by dysfunctional parenting, especially regarding externalizing problems. The effects of contextual factors on grandchildren's adjustment were also indirect. The model's measurement and structural components were largely invariant across grandmothers' race and age, as well as grandchildren's gender and age. Group differences were more prevalent regarding the magnitude of latent means for model constructs. We conclude that parenting models like the FSM are useful for investigating custodial grandfamilies.
Smith, Gregory C.; Palmieri, Patrick A.; Hancock, Gregory R.; Richardson, Rhonda A.
2009-01-01
An adaptation of the Family Stress Model (FSM) with hypothesized linkages between family contextual factors, custodial grandmothers' psychological distress, parenting practices, and grandchildren's adjustment was tested with structural equation modeling. Interview data from 733 custodial grandmothers of grandchildren between ages 4-17 revealed that the effect of grandmothers' distress on grandchildren's adjustment was mediated by dysfunctional parenting, especially regarding externalizing problems. The effects of contextual factors on grandchildren's adjustment were also indirect. The model's measurement and structural components were largely invariant across grandmothers' race and age, as well as grandchildren's gender and age. Group differences were more prevalent regarding the magnitude of latent means for model constructs. We conclude that parenting models like the FSM are useful for investigating custodial grandfamilies. PMID:19266869
Klein, Hugh
2011-11-01
This study examines the value of using syndemics theory as a model for understanding HIV risk taking in a population of men who are at great risk for acquiring and/or transmitting HIV. The principal aim is to provide an empirical test of the applicability of the theory to sexual risk behaviors in this particular research population. The study was based on a national random sample of 332 men who have sex with men, or MSM, who use the Internet to seek men with whom they can engage in unprotected sex. Data collection was conducted via telephone interviews between January 2008 and May 2009. As hypothesized in the syndemics theory model, attitudes toward condom use were central to understanding men's involvement in risky sex. As hypothesized, these attitudes depended on various demographic, psychological/psychosocial functioning, and sex-related preference measures. Also as hypothesized, psychological and psychosocial functioning were found to be very important to the overall model, and as expected, these factors were shaped greatly by factors such as demographic characteristics and childhood maltreatment experiences. The structural equation assessing the fit of the overall model indicated solid support for the syndemics theory approach. Overall, syndemics theory seems to apply fairly well to understanding the complexity of the factors that underlie men's risk-taking practices. The complicated interplay among factors such as attitudes toward condom use, childhood maltreatment experiences, psychological and psychosocial functioning, and substance use and abuse-all of which are central to a syndemics theory approach to studying risk-was demonstrated.
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.
10 Aspects of the Big Five in the Personality Inventory for DSM-5
DeYoung, Colin. G.; Carey, Bridget E.; Krueger, Robert F.; Ross, Scott R.
2015-01-01
DSM-5 includes a dimensional model of personality pathology, operationalized in the Personality Inventory for DSM-5 (PID-5), with 25 facets grouped into five higher-order factors resembling the Big Five personality dimensions. The present study tested how well these 25 facets could be integrated with the 10-factor structure of traits within the Big Five that is operationalized by the Big Five Aspect Scales (BFAS). In two healthy adult samples, 10-factor solutions largely confirmed our hypothesis that each of the 10 BFAS scales would be the highest loading BFAS scale on one and only one factor. Varying numbers of PID-5 scales were additional markers of each factor, and the overall factor structure in the first sample was well replicated in the second. Our results allow Cybernetic Big Five Theory (CB5T) to be brought to bear on manifestations of personality disorder, because CB5T offers mechanistic explanations of the 10 factors measured by the BFAS. Future research, therefore, may begin to test hypotheses derived from CB5T regarding the mechanisms that are dysfunctional in specific personality disorders. PMID:27032017
ERIC Educational Resources Information Center
Dolan, Conor V.; Molenaar, Peter C. M.
1994-01-01
In multigroup covariance structure analysis with structured means, the traditional latent selection model is formulated as a special case of phenotypic selection. Illustrations with real and simulated data demonstrate how one can test specific hypotheses concerning selection on latent variables. (SLD)
Fida, Roberta; Laschinger, Heather K Spence; Leiter, Michael P
Incivility has negative consequences in the workplace and remains a prevalent issue in nursing. Research has consistently linked incivility to nurse burnout and, in turn, to poor mental health and turnover intentions. To retain high-quality nurses, it is important to understand what factors might protect nurses from the negative effects of workplace mistreatment. The aim of the study was to investigate the role of relational occupational coping self-efficacy in protecting nurses from workplace incivility and related burnout and turnover intentions. A two-wave national sample of 596 Canadian nurses completed mail surveys both at Time 1 and one year later at Time 2. Structural equation modeling was used to test the hypothesized model. The model showed a good fit, and most of the hypothesized paths were significant. Overall, the results supported the hypothesized protective effect of relational occupational coping self-efficacy against incivility and later burnout, mental health, and turnover intentions. Relational occupational coping self-efficacy is an important protective factor against negative work behavior. Organizations should provide nurses with opportunities to build their coping strategies for managing job demands and difficult interpersonal interactions. Similarly, providing exposure to effective role models and providing meaningful verbal encouragement are other sources of efficacy information for building nurses' relational coping self-efficacy.
Review. Neurobiological mechanisms for opponent motivational processes in addiction.
Koob, George F; Le Moal, Michel
2008-10-12
The conceptualization of drug addiction as a compulsive disorder with excessive drug intake and loss of control over intake requires motivational mechanisms. Opponent process as a motivational theory for the negative reinforcement of drug dependence has long required a neurobiological explanation. Key neurochemical elements involved in reward and stress within basal forebrain structures involving the ventral striatum and extended amygdala are hypothesized to be dysregulated in addiction to convey the opponent motivational processes that drive dependence. Specific neurochemical elements in these structures include not only decreases in reward neurotransmission such as dopamine and opioid peptides in the ventral striatum, but also recruitment of brain stress systems such as corticotropin-releasing factor (CRF), noradrenaline and dynorphin in the extended amygdala. Acute withdrawal from all major drugs of abuse produces increases in reward thresholds, anxiety-like responses and extracellular levels of CRF in the central nucleus of the amygdala. CRF receptor antagonists block excessive drug intake produced by dependence. A brain stress response system is hypothesized to be activated by acute excessive drug intake, to be sensitized during repeated withdrawal, to persist into protracted abstinence and to contribute to stress-induced relapse. The combination of loss of reward function and recruitment of brain stress systems provides a powerful neurochemical basis for the long hypothesized opponent motivational processes responsible for the negative reinforcement driving addiction.
Khazem, Lauren R; Law, Keyne C; Green, Bradley A; Anestis, Michael D
2015-02-01
Suicidal desire in the military has been previously examined through the lens of the Interpersonal-Psychological Theory of Suicide (IPTS). However, no research has examined the impact of specific coping strategies on perceived burdensomeness, thwarted belongingness, and suicidal ideation in a large population of individuals serving in the US military. Furthermore, the factor structure of previously utilized coping clusters did not apply to our sample of military personnel. Therefore, we found a three-factor solution to be tested in this sample. We hypothesized that specific types of coping behavior clusters (Adaptive and Maladaptive) would predict both IPTS constructs and suicidal ideation. Results indicated that Adaptive and Maladaptive coping clusters predicted the IPTS constructs in the hypothesized directions. However, only the Maladaptive cluster predicted suicidal ideation. These findings implicate the need for further research and suicide prevention efforts focusing on coping strategies, specifically those that are maladaptive in nature, in relation to suicidal ideation in military members. Copyright © 2014 Elsevier Inc. All rights reserved.
[Mobbing: a meta-analysis and integrative model of its antecedents and consequences].
Topa Cantisano, Gabriela; Depolo, Marco; Morales Domínguez, J Francisco
2007-02-01
Although mobbing has been extensively studied, empirical research has not led to firm conclusions regarding its antecedents and consequences, both at personal and organizational levels. An extensive literature search yielded 86 empirical studies with 93 samples. The matrix correlation obtained through meta-analytic techniques was used to test a structural equation model. Results supported hypotheses regarding organizational environmental factors as main predictors of mobbing.
2014-08-25
11 distributed cyclic microplasticity . Recent approaches have been developed to incorporate these finite process zone effects at notches [25, 26...the distribution of microvoids [50] or microplasticity [51]. According to the hypotheses on which the weakest link theory is based, given a structure...high cycle fatigue regime, where scatter of heterogeneous microplasticity in the fatigue specimen is a common occurrence. The probability of success
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.
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
Factor structure and gender stability in the multidimensional condom attitudes scale.
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.
Scott-Baumann, James F; Morgan, Eric R
2015-07-01
The use of aromatic plants and their essential oils for ectoparasite treatment is a field of growing interest. Several species of birds regularly introduce aromatic herbs into their nests putatively to reduce parasites. The behaviour is most often seen in cavity nesting birds and after nest building has finished. The plants are included in a non-structural manner and are often strongly aromatic. Various different hypotheses have been proposed regarding the function of this behaviour; from the plants altering some non-living factor in the nest (crypsis, water loss and insulation hypotheses) to them being involved in mate selection (mate hypothesis) or even having a beneficial effect, direct or indirect, on chicks (drug or nest protection hypothesis, NPH). Many studies have been carried out over the years observing and experimentally testing these hypotheses. This review focuses on studies involving the most popular of these hypotheses, the NPH: that plants decrease nest parasites or pathogens, thereby conveying positive effects to the chicks, allowing the behaviour to evolve. Studies providing observational evidence towards this hypothesis and those experimentally testing it are discussed.
Factors affecting smartphone adoption for accessing information in medical settings.
Tahamtan, Iman; Pajouhanfar, Sara; Sedghi, Shahram; Azad, Mohsen; Roudbari, Masoud
2017-06-01
This study aimed to acquire knowledge about the factors affecting smartphone adoption for accessing information in medical settings in Iranian Hospitals. A qualitative and quantitative approach was used to conduct this study. Semi-structured interviews were conducted with 21 medical residents and interns in 2013 to identify determinant factors for smartphone adoption. Afterwards, nine relationships were hypothesised. We developed a questionnaire to test these hypotheses and to evaluate the importance of each factor. Structural equation modelling was used to analyse the causal relations between model parameters and to accurately identify determinant factors. Eight factors were identified in the qualitative phase of the study, including perceived usefulness, perceived ease of use, training, internal environment, personal experience, social impacts, observability and job related characteristics. Among the studied factors, perceived usefulness, personal experience and job related characteristics were significantly associated with attitude to use a smartphone which accounted for 64% of the variance in attitude. Perceived usefulness had the strongest impact on attitude to use a smartphone. The factors that emerged from interviews were consistent with the Technology Acceptance Model (TAM) and some previous studies. TAM is a reliable model for understanding the factors of smartphone acceptance in medical settings. © 2017 Health Libraries Group.
Moreno-Murcia, Juan A; Martínez-Galindo, Celestina; Moreno-Pérez, Víctor; Marcos, Pablo J.; Borges, Fernanda
2012-01-01
This study aimed to cross-validate the psychometric properties of the Basic Psychological Needs in Exercise Scale (BPNES) by Vlachopoulos and Michailidou, 2006 in a Spanish context. Two studies were conducted. Confirmatory factor analysis results confirmed the hypothesized three-factor solution In addition, we documented evidence of reliability, analysed as internal consistency and temporal stability. Future studies should analyse the scale's validity and reliability with different populations and check their experimental effect. Key pointsThe Basic Psychological Needs in Exercise Scale (BPNES) is valid and reliable for measuring basic psychological needs in healthy physical exercise in the Spanish context.The factor structure of three correlated factors has shown minimal invariance across gender. PMID:24149130
Signatures of DNA target selectivity by ETS transcription factors
Kim, Hye Mi
2017-01-01
ABSTRACT The ETS family of transcription factors is a functionally heterogeneous group of gene regulators that share a structurally conserved, eponymous DNA-binding domain. DNA target specificity derives from combinatorial interactions with other proteins as well as intrinsic heterogeneity among ETS domains. Emerging evidence suggests molecular hydration as a fundamental feature that defines the intrinsic heterogeneity in DNA target selection and susceptibility to epigenetic DNA modification. This perspective invokes novel hypotheses in the regulation of ETS proteins in physiologic osmotic stress, their pioneering potential in heterochromatin, and the effects of passive and pharmacologic DNA demethylation on ETS regulation. PMID:28301293
Signatures of DNA target selectivity by ETS transcription factors.
Poon, Gregory M K; Kim, Hye Mi
2017-05-27
The ETS family of transcription factors is a functionally heterogeneous group of gene regulators that share a structurally conserved, eponymous DNA-binding domain. DNA target specificity derives from combinatorial interactions with other proteins as well as intrinsic heterogeneity among ETS domains. Emerging evidence suggests molecular hydration as a fundamental feature that defines the intrinsic heterogeneity in DNA target selection and susceptibility to epigenetic DNA modification. This perspective invokes novel hypotheses in the regulation of ETS proteins in physiologic osmotic stress, their pioneering potential in heterochromatin, and the effects of passive and pharmacologic DNA demethylation on ETS regulation.
The Theory of Planned Behavior as a Model of Heavy Episodic Drinking Among College Students
Collins, Susan E.; Carey, Kate B.
2008-01-01
This study provided a simultaneous, confirmatory test of the theory of planned behavior (TPB) in predicting heavy episodic drinking (HED) among college students. It was hypothesized that past HED, drinking attitudes, subjective norms and drinking refusal self-efficacy would predict intention, which would in turn predict future HED. Participants consisted of 131 college drinkers (63% female) who reported having engaged in HED in the previous two weeks. Participants were recruited and completed questionnaires within the context of a larger intervention study (see Collins & Carey, 2005). Latent factor structural equation modeling was used to test the ability of the TPB to predict HED. Chi-square tests and fit indices indicated good fit for the final structural models. Self-efficacy and attitudes but not subjective norms significantly predicted baseline intention, and intention and past HED predicted future HED. Contrary to hypotheses, however, a structural model excluding past HED provided a better fit than a model including it. Although further studies must be conducted before a definitive conclusion is reached, a TPB model excluding past behavior, which is arguably more parsimonious and theory driven, may provide better prediction of HED among college drinkers than a model including past behavior. PMID:18072832
The association of hospital governance with innovation in Taiwan.
Yang, Chen-Wei; Yan, Yu-Hua; Fang, Shih-Chieh; Inamdar, Syeda Noorein; Lin, Hsien-Cheng
2018-01-01
Hospitals in Taiwan are facing major changes and innovation is increasingly becoming a critical factor for remaining competitive. One determinant that can have a significant impact on innovation is hospital governance. However, there is limited prior research on the relationship between hospital governance and innovation. The purpose of this study is to propose a conceptual framework to hypothesize the relationship between governance mechanisms and innovation and to empirically test the hypotheses in hospital organizations. We examine the relationship between governance mechanisms and innovation using data on 102 hospitals in Taiwan from the Taiwan Joint Commission on Hospital Accreditation and Quality Improvement. We model governance mechanisms using board structure, information transparency and strategic decision-making processes. For our modeling and data analysis we use measurement and structural models. We find that in hospital governance, information transparency and strategic decision making did impact innovation. However, governance structure did not. To facilitate innovation, hospital boards can increase information transparency and improve the decision-making process when considering strategic investments in innovative initiatives. To remain competitive, hospital boards need to develop and monitor indices that measure hospital innovation to ensure ongoing progress. Copyright © 2017 John Wiley & Sons, Ltd.
Lynch, Shannon M; Rebbeck, Timothy R
2013-04-01
To address the complex nature of cancer occurrence and outcomes, approaches have been developed to simultaneously assess the role of two or more etiologic agents within hierarchical levels including the: (i) macroenvironment level (e.g., health care policy, neighborhood, or family structure); (ii) individual level (e.g., behaviors, carcinogenic exposures, socioeconomic factors, and psychologic responses); and (iii) biologic level (e.g., cellular biomarkers and inherited susceptibility variants). Prior multilevel approaches tend to focus on social and environmental hypotheses, and are thus limited in their ability to integrate biologic factors into a multilevel framework. This limited integration may be related to the limited translation of research findings into the clinic. We propose a "Multi-level Biologic and Social Integrative Construct" (MBASIC) to integrate macroenvironment and individual factors with biology. The goal of this framework is to help researchers identify relationships among factors that may be involved in the multifactorial, complex nature of cancer etiology, to aid in appropriate study design, to guide the development of statistical or mechanistic models to study these relationships, and to position the results of these studies for improved intervention, translation, and implementation. MBASIC allows researchers from diverse fields to develop hypotheses of interest under a common conceptual framework, to guide transdisciplinary collaborations, and to optimize the value of multilevel studies for clinical and public health activities.
Andersen, Rikke Sand; Vedsted, Peter; Olesen, Frede; Bro, Flemming; Søndergaard, Jens
2011-09-01
The absence of a more significant improvement in cancer survival in countries such as the UK and Denmark may be partly rooted in delayed care-seeking among cancer patients. Past research on patient delay has mainly focused on patient characteristics (e.g. sociodemographic and psychological factors and symptom recognition) as causes of delayed care-seeking, while few studies have examined how the organizational structure of health care systems may influence patients' reflections on seeking care. The aim of this study was to explore this relationship. The analysis presented is based on semi-structured interviews with 30 cancer patients and their families. The article raises two hypotheses on the relationship between structural elements of a health care system and people's reflections on seeking health care: (1) Gatekeeping introduces an asymmetrical relationship between the patient and the GP which potentially results in self-restricting care-seeking, (2) Continuity in the doctor-patient relationship may negatively influence patient reflections on access to health care, as the focus shifts from the medical issues of the consultation to reflections on how to properly interact with the GP and the system in which she/he is situated. It is concluded that these hypotheses form a sound basis for further primary care research on how the organizational structure of health care systems influences patient reflections on access to medical care.
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.
Orloff, Natalia C.; Hormes, Julia M.
2014-01-01
Women in the United States experience an increase in food cravings at two specific times during their life, (1) perimenstrually and (2) prenatally. The prevalence of excess gestational weight gain (GWG) is a growing concern due to its association with adverse health outcomes in both mothers and children. To the extent that prenatal food cravings may be a determinant of energy intake in pregnancy, a better understanding of craving etiology could be crucial in addressing the issue of excessive GWG. This paper reviews the available literature to corroborate and/or dispute some of the most commonly accepted hypotheses regarding the causes of food cravings during pregnancy, including a role of (1) hormonal changes, (2) nutritional deficits, (3) pharmacologically active ingredients in the desired foods, and (4) cultural and psychosocial factors. An existing model of perimenstrual chocolate craving etiology serves to structure the discussion of these hypotheses. The main hypotheses discussed receive little support, with the notable exception of a postulated role of cultural and psychosocial factors. The presence of cravings during pregnancy is a common phenomenon across different cultures, but the types of foods desired and the adverse impact of cravings on health may be culture-specific. Various psychosocial factors appear to correlate with excess GWG, including the presence of restrained eating. Findings strongly suggest that more research be conducted in this area. We propose that future investigations fall into one of the four following categories: (1) validation of food craving and eating-related measures specifically in pregnant populations, (2) use of ecological momentary assessment to obtain real time data on cravings during pregnancy, (3) implementation of longitudinal studies to address causality between eating disorder symptoms, food cravings, and GWG, and (4) development of interventions to ensure proper prenatal nutrition and prevent excess GWG. PMID:25295023
Factors limiting the establishment of canopy-forming algae on artificial structures
NASA Astrophysics Data System (ADS)
Cacabelos, Eva; Martins, Gustavo M.; Thompson, Richard; Prestes, Afonso C. L.; Azevedo, José Manuel N.; Neto, Ana I.
2016-11-01
Macroalgal canopies are important ecosystem engineers, contributing to coastal productivity and supporting a rich assemblage of associated flora and fauna. However, they are often absent from infrastructures such as coastal defences and there has been a worldwide decline in their distribution in urbanised coastal areas. The macroalga Fucus spiralis is the only high-shore canopy forming species present in the Azores. It is widely distributed in the archipelago but is never found on coastal infrastructures. Here we evaluate factors that may potentially limit its establishment on artificial structures. A number of observational and manipulative experiments were used to test the hypotheses that: (i) limited-dispersal ability limits the colonisation of new plants onto artificial structures, (ii) vertical substratum slope negatively influences the survivorship of recruits, and (iii) vertical substratum slope also negatively influences the survivorship and fitness of adults. Results showed that the limited dispersal from adult plants may be a more important factor than slope in limiting the species ability to colonise coastal infrastructures, since the vertical substratum slope does not affect its fitness or survivorship.
Ten aspects of the Big Five in the Personality Inventory for DSM-5.
DeYoung, Colin G; Carey, Bridget E; Krueger, Robert F; Ross, Scott R
2016-04-01
Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5) includes a dimensional model of personality pathology, operationalized in the Personality Inventory for DSM-5 (PID-5), with 25 facets grouped into 5 higher order factors resembling the Big Five personality dimensions. The present study tested how well these 25 facets could be integrated with the 10-factor structure of traits within the Big Five that is operationalized by the Big Five Aspect Scales (BFAS). In 2 healthy adult samples, 10-factor solutions largely confirmed our hypothesis that each of the 10 BFAS would be the highest loading BFAS on 1 and only 1 factor. Varying numbers of PID-5 scales were additional markers of each factor, and the overall factor structure in the first sample was well replicated in the second. Our results allow Cybernetic Big Five Theory (CB5T) to be brought to bear on manifestations of personality disorder, because CB5T offers mechanistic explanations of the 10 factors measured by the BFAS. Future research, therefore, may begin to test hypotheses derived from CB5T regarding the mechanisms that are dysfunctional in specific personality disorders. (c) 2016 APA, all rights reserved).
Psychometric Properties of the “Sport Motivation Scale (SMS)” Adapted to Physical Education
Granero-Gallegos, Antonio; Baena-Extremera, Antonio; Gómez-López, Manuel; Sánchez-Fuentes, José Antonio; Abraldes, J. Arturo
2014-01-01
The aim of this study was to investigate the factor structure of a Spanish version of the Sport Motivation Scale adapted to physical education. A second aim was to test which one of three hypothesized models (three, five and seven-factor) provided best model fit. 758 Spanish high school students completed the Sport Motivation Scale adapted for Physical Education and also completed the Learning and Performance Orientation in Physical Education Classes Questionnaire. We examined the factor structure of each model using confirmatory factor analysis and also assessed internal consistency and convergent validity. The results showed that all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model (χ2/gl = 2.73; ECVI = 1.38) as it produces better values when adapted to physical education, that five-factor model (χ2/gl = 2.82; ECVI = 1.44) and three-factor model (χ2/gl = 3.02; ECVI = 1.53). Key Points Physical education research conducted in Spain has used the version of SMS designed to assess motivation in sport, but validity reliability and validity results in physical education have not been reported. Results of the present study lend support to the factorial validity and internal reliability of three alternative factor structures (3, 5, and 7 factors) of SMS adapted to Physical Education in Spanish. Although all three models in Spanish produce good indicators of fitness, but we suggest using the seven-factor model. PMID:25435772
Factors Affecting Career Decision Making of Mexican and Mexican-American Students.
ERIC Educational Resources Information Center
Newlon, Betty J.; Borboa, Roman
The purpose of this research was to identify the self-reported factors affecting the career decision making of Mexican and Mexican-American students. It was hypothesized that the factor clusters would differ between the two sample populations, Mexican and Mexican-American. It was also hypothesized that these clusters would differ from six clusters…
Impact of scaffolding and question structure on the gender gap
NASA Astrophysics Data System (ADS)
Dawkins, Hillary; Hedgeland, Holly; Jordan, Sally
2017-12-01
We address previous hypotheses about possible factors influencing the gender gap in attainment in physics. Specifically, previous studies claim that scaffolding may preferentially benefit female students, and we present some alternative conclusions surrounding this hypothesis. By taking both student attainment level and the degree of question scaffolding into account, we identify questions that exhibit real bias in favor of male students. We find that both multidimensional context and use of diagrams are common elements of such questions.
Van Wijhe, Corine I; Peeters, Maria C W; Schaufeli, Wilmar B
2011-12-01
Although workaholics and work engaged employees both work long hours, they seem to have a different underlying motivation to do so. The mood as input model might offer an explanation for the difference in work persistence of these employees. This model suggests that the interplay of mood and "persistence rules" (enough and enjoyment rules) may lead to different kinds of persistence mechanisms. The aims of this study are to present a scale for measuring persistence rules, the Work Persistence rules Checklist (WoPeC), to analyze its psychometric properties and to test the mood as input model in relationship with workaholism and work engagement. Structural equation modeling was used to analyze the data. Results of a confirmatory factor analysis in study 1 provided support for the hypothesized factor structure of the WoPeC. In study 2, it appeared that the use of an enough and an enjoyment rule for determining when to continue working is related to workaholism and work engagement, respectively. Furthermore, it was hypothesized and found that negative mood is related to workaholism, whereas positive mood is associated with work engagement. The expected interactions between mood and persistence rules on workaholism and work engagement were not demonstrated. Mood and persistence rules seem relevant for explaining the difference between workaholism and work engagement.
Waldman, Irwin D; Poore, Holly E; van Hulle, Carol; Rathouz, Paul J; Lahey, Benjamin B
2016-11-01
Several recent studies of the hierarchical phenotypic structure of psychopathology have identified a General psychopathology factor in addition to the more expected specific Externalizing and Internalizing dimensions in both youth and adult samples and some have found relevant unique external correlates of this General factor. We used data from 1,568 twin pairs (599 MZ & 969 DZ) age 9 to 17 to test hypotheses for the underlying structure of youth psychopathology and the external validity of the higher-order factors. Psychopathology symptoms were assessed via structured interviews of caretakers and youth. We conducted phenotypic analyses of competing structural models using Confirmatory Factor Analysis and used Structural Equation Modeling and multivariate behavior genetic analyses to understand the etiology of the higher-order factors and their external validity. We found that both a General factor and specific Externalizing and Internalizing dimensions are necessary for characterizing youth psychopathology at both the phenotypic and etiologic levels, and that the 3 higher-order factors differed substantially in the magnitudes of their underlying genetic and environmental influences. Phenotypically, the specific Externalizing and Internalizing dimensions were slightly negatively correlated when a General factor was included, which reflected a significant inverse correlation between the nonshared environmental (but not genetic) influences on Internalizing and Externalizing. We estimated heritability of the general factor of psychopathology for the first time. Its moderate heritability suggests that it is not merely an artifact of measurement error but a valid construct. The General, Externalizing, and Internalizing factors differed in their relations with 3 external validity criteria: mother's smoking during pregnancy, parent's harsh discipline, and the youth's association with delinquent peers. Multivariate behavior genetic analyses supported the external validity of the 3 higher-order factors by suggesting that the General, Externalizing, and Internalizing factors were correlated with peer delinquency and parent's harsh discipline for different etiologic reasons. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Vestigial Biological Structures: A Classroom-Applicable Test of Creationist Hypotheses
ERIC Educational Resources Information Center
Senter, Phil; Ambrocio, Zenis; Andrade, Julia B.; Foust, Katanya K.; Gaston, Jasmine E.; Lewis, Ryshonda P.; Liniewski, Rachel M.; Ragin, Bobby A.; Robinson, Khanna L.; Stanley, Shane G.
2015-01-01
Lists of vestigial biological structures in biology textbooks are so short that some young-Earth creationist authors claim that scientists have lost confidence in the existence of vestigial structures and can no longer identify any verifiable ones. We tested these hypotheses with a method that is easily adapted to biology classes. We used online…
[The influences of interaction during online gaming on sociability and aggression in real life].
Fuji, Kei; Yoshida, Fujio
2010-02-01
This study examined the influences of online gaming on sociability and aggression in real life. It was hypothesized that the effects of online gaming would differ depending on the interaction style of the online-gamers. Online-gamers in Japan (n = 1 477) were asked to respond to questionnaires that measured interaction style during online gaming, the effects of sociability and aggression, as well as social and individual orientation in real life. Factor analysis of the scores for interaction style extracted five factors. Covariance structure analysis indicated that sociable interactions such as "Broadening relations" and "Feeling of belonging" promoted sociability in real life. In addition, "Release from daily hassles" promoted sociability and decreased aggression. In contrast, non-sociable and aggressive interactions decreased sociability and increased aggression. The results also suggested that a social orientation in real life promoted sociable interactions during game playing, while an individual orientation promoted non-sociable and aggressive interactions. These results supported the hypotheses and suggested that online gaming resulted in positive outcomes for those who are socially, but negative outcomes for those who are not.
Effects of Spaceflight on Venous and Arterial Compliance
NASA Technical Reports Server (NTRS)
Platts, S. H.; Pibeiro, L. C.; Laurie, S. S.; Lee, S. M. C.; Martin, D. S.; Ploutz-Snyder, R.; Stenger, M. B.
2016-01-01
The visual impairment and intracranial pressure (VIIP) syndrome is a spaceflight-associated medical condition consisting of a constellation of symptoms affecting less than 70% of American astronauts who have flown International Space Station (ISS) missions. VIIP is defined primarily by visual acuity deficits and anatomical changes to eye structures and is hypothesized to be related to elevated intracranial pressure secondary to spaceflight-induced cephalad fluid shifts, although other space flight factors (e.g., diet, environmental factors) may contribute. Loss of visual acuity could be a significant threat to crew health and performance during and after an exploration mission and may have implications for years postflight.
[Masculinity and femininity scales: current state of the art].
Fernández, Juan; Quiroga, María A; Del Olmo, Isabel; Rodríguez, Antonio
2007-08-01
A theoretical and empirical review of masculinity and femininity scales was carried out after 30 years of their existence. Hypotheses to be tested were: (a) muldimensionality versus bidimensionality; (b) inadequate percentage of variance accounted for (less than 50%); (c) inconsistency between factor structure and the dualistic model. 618, 200 and 287 students took part in each of the three studies that were carried out. Factorial analyses (PAF) were performed. Results support multidimensionality, unsatisfactory percentage of variance accounted for, and lack of congruence between obtained factors and the dualistic model. All these data were analysed within the context of the twofold sex and gender reality model.
The roles of social factor and internet self-efficacy in nurses' web-based continuing learning.
Chiu, Yen-Lin; Tsai, Chin-Chung
2014-03-01
This study was conducted to explore the relationships among social factor, Internet self-efficacy and attitudes toward web-based continuing learning in a clinical nursing setting. The participants recruited were 244 in-service nurses from hospitals in Taiwan. Three instruments were used to assess their perceptions of social factor, Internet self-efficacy (including basic and advanced Internet self-efficacy) and attitudes toward web-based continuing learning (including perceived usefulness, perceived ease of use, affection and behavior). Structural equation modeling (SEM) was utilized to identify the hypothesized structural model. The results of this study support that social factor is a significant factor correlated to Internet self-efficacy and attitudes toward web-based continuing learning (including perceived usefulness, perceived ease of use and affection). In addition, nurses' basic Internet self-efficacy plays a key role in attitudes including perceived usefulness, perceived ease of use and affection. However, advanced self-efficacy was not correlated to any of the attitudes. The behavior dimension was not linked to social factor or Internet self-efficacy, but was linked to perceived ease of use and affection. Copyright © 2013 Elsevier Ltd. All rights reserved.
Fok, Carlotta Ching Ting; Allen, James; Henry, David
2014-02-01
The Relationship dimension of the Family Environment Scale, which consists of the Cohesion, Expressiveness, and Conflict subscales, measures a person's perception of the quality of his or her family relationship functioning. This study investigates an adaptation of the Relationship dimension of the Family Environment Scale for Alaska Native youth. The authors tested the adapted measure, the Brief Family Relationship Scale, for psychometric properties and internal structure with 284 12- to 18-year-old predominately Yup'ik Eskimo Alaska Native adolescents from rural, remote communities. This non-Western cultural group is hypothesized to display higher levels of collectivism traditionally organized around an extended kinship family structure. Results demonstrate a subset of the adapted items function satisfactorily, a three-response alternative format provided meaningful information, and the subscale's underlying structure is best described through three distinct first-order factors, organized under one higher order factor. Convergent and discriminant validity of the Brief Family Relationship Scale was assessed through correlational analysis.
Schürmann, Tim; Beckerle, Philipp; Preller, Julia; Vogt, Joachim; Christ, Oliver
2016-12-19
In product development for lower limb prosthetic devices, a set of special criteria needs to be met. Prosthetic devices have a direct impact on the rehabilitation process after an amputation with both perceived technological and psychological aspects playing an important role. However, available psychometric questionnaires fail to consider the important links between these two dimensions. In this article a probabilistic latent trait model is proposed with seven technical and psychological factors which measure satisfaction with the prosthesis. The results of a first study are used to determine the basic parameters of the statistical model. These distributions represent hypotheses about factor loadings between manifest items and latent factors of the proposed psychometric questionnaire. A study was conducted and analyzed to form hypotheses for the prior distributions of the questionnaire's measurement model. An expert agreement study conducted on 22 experts was used to determine the prior distribution of item-factor loadings in the model. Model parameters that had to be specified as part of the measurement model were informed prior distributions on the item-factor loadings. For the current 70 items in the questionnaire, each factor loading was set to represent the certainty with which experts had assigned the items to their respective factors. Considering only the measurement model and not the structural model of the questionnaire, 70 out of 217 informed prior distributions on parameters were set. The use of preliminary studies to set prior distributions in latent trait models, while being a relatively new approach in psychological research, provides helpful information towards the design of a seven factor questionnaire that means to identify relations between technical and psychological factors in prosthetic product design and rehabilitation medicine.
Kwok, Cannas; Endrawes, Gihane; Lee, Chun Fan
2016-02-01
The aim of the study was to report the psychometric properties of the Arabic version of the Breast Cancer Screening Beliefs Questionnaire (BCSBQ). A convenience sample of 251 Arabic-Australian women was recruited from a number of Arabic community organizations. Construct validity was examined by Cuzick's non-parametric test while Cronbach α was used to assess internal consistency reliability. Explanatory factor analysis was conducted to study the factor structure. The results indicated that the Arabic version of the BCSBQ had satisfactory validity and internal consistency. The Cronbach's alpha of the three subscales ranged between 0.810 and 0.93. The frequency of breast cancer screening practices (breast awareness, clinical breast-examination and mammography) were significantly associated with attitudes towards general health check-up and perceived barriers to mammographic screening. Exploratory factor analysis showed a similar fit for the hypothesized three-factor structure with our data set. The Arabic version of the BCBSQ is a culturally appropriate, valid and reliable instrument for assessing the beliefs, knowledge and attitudes to breast cancer and breast cancer screening practices among Arabic-Australian women. Copyright © 2015 Elsevier Ltd. All rights reserved.
McDonough, Christine M.; Jette, Alan M.; Ni, Pengsheng; Bogusz, Kara; Marfeo, Elizabeth E; Brandt, Diane E; Chan, Leighton; Meterko, Mark; Haley, Stephen M.; Rasch, Elizabeth K.
2014-01-01
Objectives To build a comprehensive item pool representing work-relevant physical functioning and to test the factor structure of the item pool. These developmental steps represent initial outcomes of a broader project to develop instruments for the assessment of function within the context of Social Security Administration (SSA) disability programs. Design Comprehensive literature review; gap analysis; item generation with expert panel input; stakeholder interviews; cognitive interviews; cross-sectional survey administration; and exploratory and confirmatory factor analyses to assess item pool structure. Setting In-person and semi-structured interviews; internet and telephone surveys. Participants A sample of 1,017 SSA claimants, and a normative sample of 999 adults from the US general population. Interventions Not Applicable. Main Outcome Measure Model fit statistics Results The final item pool consisted of 139 items. Within the claimant sample 58.7% were white; 31.8% were black; 46.6% were female; and the mean age was 49.7 years. Initial factor analyses revealed a 4-factor solution which included more items and allowed separate characterization of: 1) Changing and Maintaining Body Position, 2) Whole Body Mobility, 3) Upper Body Function and 4) Upper Extremity Fine Motor. The final 4-factor model included 91 items. Confirmatory factor analyses for the 4-factor models for the claimant and the normative samples demonstrated very good fit. Fit statistics for claimant and normative samples respectively were: Comparative Fit Index = 0.93 and 0.98; Tucker-Lewis Index = 0.92 and 0.98; Root Mean Square Error Approximation = 0.05 and 0.04. Conclusions The factor structure of the Physical Function item pool closely resembled the hypothesized content model. The four scales relevant to work activities offer promise for providing reliable information about claimant physical functioning relevant to work disability. PMID:23542402
Strength conditions for the elastic structures with a stress error
NASA Astrophysics Data System (ADS)
Matveev, A. D.
2017-10-01
As is known, the constraints (strength conditions) for the safety factor of elastic structures and design details of a particular class, e.g. aviation structures are established, i.e. the safety factor values of such structures should be within the given range. It should be noted that the constraints are set for the safety factors corresponding to analytical (exact) solutions of elasticity problems represented for the structures. Developing the analytical solutions for most structures, especially irregular shape ones, is associated with great difficulties. Approximate approaches to solve the elasticity problems, e.g. the technical theories of deformation of homogeneous and composite plates, beams and shells, are widely used for a great number of structures. Technical theories based on the hypotheses give rise to approximate (technical) solutions with an irreducible error, with the exact value being difficult to be determined. In static calculations of the structural strength with a specified small range for the safety factors application of technical (by the Theory of Strength of Materials) solutions is difficult. However, there are some numerical methods for developing the approximate solutions of elasticity problems with arbitrarily small errors. In present paper, the adjusted reference (specified) strength conditions for the structural safety factor corresponding to approximate solution of the elasticity problem have been proposed. The stress error estimation is taken into account using the proposed strength conditions. It has been shown that, to fulfill the specified strength conditions for the safety factor of the given structure corresponding to an exact solution, the adjusted strength conditions for the structural safety factor corresponding to an approximate solution are required. The stress error estimation which is the basis for developing the adjusted strength conditions has been determined for the specified strength conditions. The adjusted strength conditions presented by allowable stresses are suggested. Adjusted strength conditions make it possible to determine the set of approximate solutions, whereby meeting the specified strength conditions. Some examples of the specified strength conditions to be satisfied using the technical (by the Theory of Strength of Materials) solutions and strength conditions have been given, as well as the examples of stress conditions to be satisfied using approximate solutions with a small error.
NASA Astrophysics Data System (ADS)
MacMillan, Mitchell R.; Duarte, Cristian; Quijón, Pedro A.
2017-07-01
Most literature suggests that sandy beach macrobenthic communities are structured by physical factors. However, an aspect that has not been studied in detail is whether those physical factors change with erosion or the association of beaches to backshore features like sand dunes, till bluffs, and sandstone cliffs. We addressed this question by sampling 14 sandy beaches on the north shore of Prince Edward Island, Atlantic Canada. Two null hypotheses were tested: first, there is no relationship between physical factors and community descriptors across sandy beaches, and second, there is no difference among beaches associated with distinct backshore features both in terms of physical factors and community descriptors. In order to test these hypotheses, samples of macrobenthic organisms and measurements of grain size, slope, beach deposit index and erosion rates were obtained. Our surveys collected a total of 14 taxa numerically dominated by the spionid polychaete Scolelepis squamata. With regards to the first hypothesis, regression analyses showed that community descriptors were all positively related to erosion rates while unrelated to the variation in grain size, slope and beach deposit index. As for the second hypothesis, erosion rates were significantly different among beaches associated to till bluffs (highest), dunes and sandstone cliffs (lowest). Meanwhile, the other physical factors did not significantly differ among backshore features. Species richness was highest in beaches associated to till bluffs and lowest in those associated to sandstone cliffs. Abundance values were also lowest in beaches associated to sandstone cliffs, and their community composition was significantly different to those associated to dunes and till bluffs. We suggest that the relationship between erosion rates and community descriptors is complex and may be mediated by the availability of nutrients: higher erosion levels might account for higher concentrations of nutrients for suspension feeders, the numerically dominant organisms in this system. We call for further attention to the relationship between erosion and suspended nutrients.
Gene Expression and Structural Skeletal Responses to Long-Duration Simulated Microgravity in Rats
NASA Technical Reports Server (NTRS)
Shirazi-Fard, Yasaman; Rael, Victoria E.; Torres, Samantha; Steczina, Sonette; Bryant, Sheenah; Tahimic, Candice; Globus, Ruth K.
2017-01-01
In this study, we aim to examine skeletal responses to simulated long-duration spaceflight (90 days) and weight-bearing recovery on bone loss using the ground-based hindlimb unloading (HU) model in adolescent (3-month old) male rats. We hypothesized that simulated microgravity leads to the temporal regulation of oxidative defense genes and pro-bone resorption factors, where there is a progression and eventual plateau; furthermore, early transient changes in these pathways precede skeletal adaptations.
Depression, stress, and blood pressure in urban African-American women.
Artinian, Nancy T; Washington, Olivia G M; Flack, John M; Hockman, Elaine M; Jen, Kai-Lin Catherine
2006-01-01
African-American women have disturbingly high rates of hypertension, exceeding those of African-American men and other ethnic groups. Reasons for these disparities are not understood. Depression, more common in women than men, has been linked to endothelial dysfunction, inflammation, metabolic and hematologic abnormalities, and increased sympathetic nervous system activity--all factors associated with cardiovascular disease. A descriptive correlational design was used to test the following hypotheses: 1) African-American women with higher levels of depression will have higher blood pressure (BP) levels, more cardiovascular risk factors, greater stress, and lower social support; and 2) depression will mediate the relationship between stress and BP. A convenience sample of 245 hypertensive African-American women (mean age, 61+/-12.7 years) was recruited through free BP screenings offered in the community. All data were collected during a structured interview and brief physical examination. Pearson r correlation coefficients, analysis of variance, and multiple regression analyses were used to analyze the hypotheses. Women with higher levels of depression had higher diastolic BP and were more likely to smoke, eat fewer fruits and vegetables, and have more stress and less social support. Depression mediated the relationship between stress and diastolic BP. The findings emphasize the importance of assessing both behavioral and psychosocial factors in urban African-American women with hypertension.
Bipolar Pathophysiology and Development of Improved Treatments
Bowden, Charles L.
2013-01-01
The purpose of this review is to provide strategies and their rationale which can facilitate scientifically productive investigations into genetic, neuronal, brain functional and clinical aspects of bipolar disorder. The presentation addresses both factors that have impeded and those that have facilitated landmark advances on the pathophysiology and treatment of bipolar disorders. Application of the strategies can provide a scientific platform that may be useful to basic and clinical scientists for the purposes of achieving seminal advances in understanding pathophysiology, including inherited and experience based contributors to disease expression. Current diagnostic criteria omit certain key symptoms, do not include illness course or family history and lack specification of the importance of fundamental symptomatology. Consideration of such factors in inclusion and exclusion criteria, and in assessment instruments in basic and clinical studies, serves to strengthen the capability of a research plan to test key hypotheses regarding moderating and mediating factors of this complex illness. For example, most studies of brain structure and function and of new interventions have selected subjects on the basis of traditional full syndromal criteria. Evidence indicates that additional consideration of principal behavioral domains of bipolar symptomatology, e.g., anxiety, psychosis, impulsivity, elevated psychomotor and cognitive processing speed, rather than strictly depressive or manic syndromes can provide more homogeneous samples for study, and increase the focus of experimental hypotheses. PMID:18582440
Andersen, Rikke Sand; Vedsted, Peter; Olesen, Frede; Bro, Flemming; Søndergaard, Jens
2011-01-01
Objective The absence of a more significant improvement in cancer survival in countries such as the UK and Denmark may be partly rooted in delayed care-seeking among cancer patients. Past research on patient delay has mainly focused on patient characteristics (e.g. sociodemographic and psychological factors and symptom recognition) as causes of delayed care-seeking, while few studies have examined how the organizational structure of health care systems may influence patients’ reflections on seeking care. The aim of this study was to explore this relationship. Design The analysis presented is based on semi-structured interviews with 30 cancer patients and their families. Results The article raises two hypotheses on the relationship between structural elements of a health care system and people's reflections on seeking health care: (1) Gatekeeping introduces an asymmetrical relationship between the patient and the GP which potentially results in self-restricting care-seeking, (2) Continuity in the doctor–patient relationship may negatively influence patient reflections on access to health care, as the focus shifts from the medical issues of the consultation to reflections on how to properly interact with the GP and the system in which she/he is situated. Conclusion It is concluded that these hypotheses form a sound basis for further primary care research on how the organizational structure of health care systems influences patient reflections on access to medical care. PMID:21861597
Nguyen, Trang Quynh; Poteat, Tonia; Bandeen-Roche, Karen; German, Danielle; Nguyen, Yen Hai; Vu, Loan Kieu-Chau; Nguyen, Nam Thi-Thu; Knowlton, Amy R
2016-08-01
We developed the first Vietnamese Internalized Homophobia (IH) scale for use with Vietnamese sexual minority women (SMW). Drawing from existing IH scales in the international literature and based on prior qualitative research about SMW in the Viet Nam context, the scale covers two domains: self-stigma (negative attitudes toward oneself as a sexual minority person) and sexual prejudice (negative attitudes toward homosexuality/same-sex relations in general). Scale items, including items borrowed from existing scales and items based on local expressions, were reviewed and confirmed by members of the target population. Quantitative evaluation used data from an anonymous web-based survey of Vietnamese SMW, including those who identified as lesbian (n = 1187), or as bisexual (n = 641) and those who were unsure about their sexual identity (n = 353). The scale was found to consist of two highly correlated factors reflecting self-stigma (not normal/wholesome and self-reproach and wishing away same-sex sexuality) and one factor reflecting sexual prejudice, and to have excellent internal consistency. Construct validity was evidenced by subscale associations with a wide range of hypothesized correlates, including perceived sexual stigma, outness, social support, connection to other SMW, relationship quality, psychological well-being, anticipation of heterosexual marriage, and endorsement of same-sex marriage legalization. Self-stigma was more strongly associated with psychosocial correlates, and sexual prejudice was more associated with endorsement of legal same-sex marriage. The variations in these associations across the hypothesized correlates and across sexual identity groups were consistent with the minority stress model and the IH literature, and exhibited context-specific features, which are discussed.
Nguyen, Trang Quynh; Poteat, Tonia; Bandeen-Roche, Karen; German, Danielle; Nguyen, Yen Hai; Vu, Loan Kieu-Chau; Nguyen, Nam Thi-Thu; Knowlton, Amy R.
2016-01-01
We developed the first Vietnamese internalized homophobia (IH) scale, for use with Vietnamese sexual minority women (SMW). Drawing from existing IH scales in the international literature and based on prior qualitative research about SMW in the Viet Nam context, the scale covers two domains: self-stigma (negative attitudes toward oneself as a sexual minority person) and sexual prejudice (negative attitudes toward homosexuality/same-sex relations in general). Scale items, including items borrowed from existing scales and items based on local expressions, were reviewed and confirmed by members of the target population. Quantitative evaluation used data from an anonymous web-based survey of Vietnamese SMW, including those who identified as lesbian (n=1187), or as bisexual (n=641) and those who were unsure about their sexual identity (n=353). The scale was found to consist of two highly correlated factors reflecting self-stigma (not normal/wholesome and self-reproach and wishing away same-sex sexuality) and one factor reflecting sexual prejudice, and to have excellent internal consistency. Construct validity was evidenced by subscales’ associations with a wide range of hypothesized correlates including perceived sexual stigma, outness, social support, connection to other SMW, relationship quality, psychological well-being, anticipation of heterosexual marriage and endorsement of same-sex marriage legalization. Self-stigma was more strongly associated with psychosocial correlates and sexual prejudice was more associated with endorsement of legal same-sex marriage. The variations in these associations across the hypothesized correlates and across sexual identity groups were consistent with the Minority Stress Model and the IH literature, and exhibited context-specific features, which are discussed. PMID:27007469
Richmond, Katherine; Levant, Ronald; Smalley, Bryant; Cook, Stephen
2015-01-01
The purpose of this study was to conduct a confirmatory factor analytic investigation of the Femininity Ideology Scale (FIS) and to assess whether feminine gender role stress mediated the relationship between femininity ideology and anxiety. During the 2010-2011 academic year, a convenience sample of 606 college women were recruited from three universities and one college. Confirmatory factor analysis supported a four- versus the hypothesized five-factor model, resulting in the elimination of the Dependency/Deference factor. Mediation analysis using structural equation modeling indicated no direct relationship between Femininity Ideology and Anxiety, although an indirect one was observed, mediated through Feminine Gender Role Stress. The results are discussed in terms of possible changes in contemporary notions of femininity, and the utility of using the FIS in applied therapeutic settings.
Fok, Carlotta Ching Ting; Allen, James; Henry, David; Mohatt, Gerald V
2012-06-01
Self-mastery refers to problem-focused coping facilitated through personal agency. Communal mastery describes problem solving through an interwoven social network. This study investigates an adaptation of self- and communal mastery measures for youth. Given the important distinction between family and peers in the lives of youth, these adaptation efforts produced Mastery-Family and Mastery-Friends subscales, along with a Mastery-Self subscale. We tested these measures for psychometric properties and internal structure with 284 predominately Yup'ik Eskimo Alaska Native adolescents (12- to 18-year-olds) from rural, remote communities-a non-Western culturally distinct group hypothesized to display higher levels of collectivism and communal mastery. Results demonstrate a subset of items adapted for youth function satisfactorily, a 3-response alternative format provided meaningful information, and the subscale's underlying structure is best described through 3 distinct first-order factors organized under 1 higher order mastery factor. (c) 2012 APA, all rights reserved
Aging and social networks in Spain: the importance of pubs and churches.
Buz, José; Sanchez, Marta; Levenson, Michael R; Aldwin, Carolyn M
2014-01-01
We examined whether the social convoy model and socioemotional selectivity theory apply in collectivistic cultures by examining the contextual factors which are hypothesized to mediate age-related differences in social support in a collectivist European country. Five hundred Spanish community-dwelling older adults (Mean age = 74.78, SD = 7.76, range = 60-93) were interviewed to examine structural aspects of their social networks. We found that age showed highly complex relationships with network size and frequency of interaction, depending on the network circle and the mediation of cultural factors. Family structure was important for social relations in the inner circle, while pubs and churches were important for peripheral relations. Surprisingly, pub attendance was the most important variable for maintenance of social support of peripheral network members. In general, the results support the applicability of the social convoy and socioemotional selectivity constructs to social support among Spanish older adults.
Fok, Carlotta Ching Ting; Allen, James; Henry, David; Mohatt, Gerald V.
2012-01-01
Self-mastery refers to problem-focused coping facilitated through personal agency. Communal mastery describes problem solving through an interwoven social network. This study investigates an adaptation of self- and communal mastery measures for youth. Given the important distinction between family and peers in the lives of youth, these adaptation efforts produced Mastery-Family and Mastery-Friends subscales, along with a Mastery-Self subscale. We tested these measures for psychometric properties and internal structure with 284 12 to 18-year-old predominately Yup’ik Eskimo Alaska Native adolescents from rural, remote communities — a non-Western culturally distinct group hypothesized to display higher levels of collectivism and communal mastery. Results demonstrate a subset of items adapted for youth function satisfactorily, a three-response alternative format provided meaningful information, and the subscale’s underlying structure is best described through three distinct first-order factors organized under one higher order mastery factor. PMID:21928912
Cárdenas Castro, Manuel
2010-02-01
The main purpose of this study was to investigate the dimensionality of a Spanish-language version of the Blatant and Subtle Prejudice Scale via exploratory (EFA) and confirmatory factor analysis (CFA). No research has confirmed the hypothesized factor structure in Latin American countries. Using data from a random and probability survey in population of the northern area of Chile (N= 896), four models were specified: single factor model (global prejudice factor), correlated two-factor model (subtle and blatant prejudice), correlated two-factor second-order model, and single-factor second-order model. The findings indicated that the two-factor second-order model had the best fit. The corresponding alpha coefficients were .82 (subtle prejudice) and .76 (blatant prejudice). Lastly, differences were examined between
A confirmatory factor analytic validation of the Tinnitus Handicap Inventory.
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.
Ehrhart, Mark G.; Torres, Elisa M.; Finn, Natalie K.; Roesch, Scott C.
2016-01-01
There have been recent calls for pragmatic measures to assess factors that influence evidence-based practice (EBP) implementation processes and outcomes. The Implementation Leadership Scale (ILS) is a brief and efficient measure that can be used for research or organizational development purposes to assess leader behaviors and actions that actively support effective EBP implementation. The ILS was developed and validated in mental health settings. This study validates the ILS factor structure with providers in alcohol and other drug (AOD) use treatment agencies. Participants were 323 service providers working in 72 workgroups from three AOD use treatment agencies. Confirmatory factor analyses and reliability analyses were conducted to examine the psychometric properties of the ILS. Convergent and discriminant validity were also assessed. Confirmatory factor analyses demonstrated good fit to the hypothesized first and second order factor structure. Internal consistency reliability was excellent. Convergent and discriminant validity was supported. The ILS psychometric characteristics, reliability, and validity were supported in AOD use treatment agencies. The ILS is a brief and pragmatic measure that can be used for research and practice to assess leadership for EBP implementation in AOD use treatment agencies. PMID:27431044
Aarons, Gregory A; Ehrhart, Mark G; Torres, Elisa M; Finn, Natalie K; Roesch, Scott C
2016-09-01
There have been recent calls for pragmatic measures to assess factors that influence evidence-based practice (EBP) implementation processes and outcomes. The Implementation Leadership Scale (ILS) is a brief and efficient measure that can be used for research or organizational development purposes to assess leader behaviors and actions that actively support effective EBP implementation. The ILS was developed and validated in mental health settings. This study validates the ILS factor structure with providers in alcohol and other drug (AOD) use treatment agencies. Participants were 323 service providers working in 72 workgroups from three AOD use treatment agencies. Confirmatory factor analyses and reliability analyses were conducted to examine the psychometric properties of the ILS. Convergent and discriminant validity were also assessed. Confirmatory factor analyses demonstrated good fit to the hypothesized first and second order factor structure. Internal consistency reliability was excellent. Convergent and discriminant validity was supported. The ILS psychometric characteristics, reliability, and validity were supported in AOD use treatment agencies. The ILS is a brief and pragmatic measure that can be used for research and practice to assess leadership for EBP implementation in AOD use treatment agencies. Copyright © 2016 Elsevier Inc. All rights reserved.
Fick, Stephen E; Decker, Cheryl E.; Duniway, Michael C.; Miller, Mark E.
2016-01-01
Anthropogenic desertification is a problem that plagues drylands globally; however, the factors which maintain degraded states are often unclear. In Canyonlands National Park on the Colorado Plateau of southeastern Utah, many degraded grasslands have not recovered structure and function >40 yr after release from livestock grazing pressure, necessitating active restoration. We hypothesized that multiple factors contribute to the persistent degraded state, including lack of seed availability, surficial soil-hydrological properties, and high levels of spatial connectivity (lack of perennial vegetation and other surface structure to retain water, litter, seed, and sediment). In combination with seeding and surface raking treatments, we tested the effect of small barrier structures (“ConMods”) designed to disrupt the loss of litter, seed and sediment in degraded soil patches within the park. Grass establishment was highest when all treatments (structures, seed addition, and soil disturbance) were combined, but only in the second year after installation, following favorable climatic conditions. We suggest that multiple limiting factors were ameliorated by treatments, including seed limitation and microsite availability, seed removal by harvester ants, and stressful abiotic conditions. Higher densities of grass seedlings on the north and east sides of barrier structures following the summer months suggest that structures may have functioned as artificial “nurse-plants”, sheltering seedlings from wind and radiation as well as accumulating wind-blown resources. Barrier structures increased the establishment of both native perennial grasses and exotic annuals, although there were species-specific differences in mortality related to spatial distribution of seedlings within barrier structures. The unique success of all treatments combined, and even then only under favorable climatic conditions and in certain soil patches, highlights that restoration success (and potentially, natural regeneration) often is contingent on many interacting factors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neff, Michael M.
This is a final report for Department of Energy Grant No. DE-FG02-08ER15927 entitled “Molecular Genetic Analysis of Activation-Tagged Transcription Factors Thought to be Involved in Photomorphogenesis”. Based on our preliminary photobiological and genetic analysis of the sob1-D mutant, we hypothesized that OBP3 is a transcription factor involved in both phytochrome and cryptochrome-mediated signal transduction. In addition, we hypothesized that OBP3 is involved in auxin signaling and root development. Based on our preliminary photobiological and genetic analysis of the sob2-D mutant, we also hypothesized that a related gene, LEP, is involved in hormone signaling and seedling development.
NASA Astrophysics Data System (ADS)
McDowell, P. F.
2016-12-01
The Middle Fork John Day River at Oxbow Conservation Area, northeastern Oregon, experienced heavy cattle grazing for a number of decades and was dredge mined for gold in the 1930s-50s. As a result of dredging, flow was divided between the original meandering channel on the southern part of the floodplain and a straight dredged channel on the northern part of the floodplain. The Confederated Tribes of the Warm Springs acquired this property and began planning floodplain and instream restoration focused primarily on anadromous and resident salmonids. In 2000, cattle grazing in the riparian zone was eliminated, resulting in expansion of sedges and other plants on banks, bars and the channel bed. In 2003, riparian planting of woody vegetation began. In 2011, log structures were constructed in the south channel. The overarching goals of the log structure project were: 1) to add bank protection and roughness to accommodate the planned increase in discharge, and 2) to provide fish cover, pools, and channel complexity. In 2013, the north channel was closed and all flow was put in the south channel. This paper examines channel morphological response to these multiple actions. Channel adjustment was monitored through repeated channel cross-section surveys, longitudinal profile surveys, and analysis of planform change using high-resolution aerial imagery. I hypothesized that channel adjustment would be greatest where banks were less protected, and where bed materials were more mobile due to smaller size or local hydraulic factors such as bend curvature. The results indicate that there has been significant reorganization of riffle-pool structure in the longitudinal profile, but less change in cross-sections and planform. Cross-sections, both at log structures and not at structures, show limited bar aggradation and bank erosion. Some modest erosion occurred on banks protected by log structures. There is no increase in pool depth. The hypothesized relationship between channel change and hydraulic factors is not supported. With healthy riparian vegetation and log structures, this reach is relatively resistant to change, yet it continues to have an active and mobile gravel-cobble bed, even in years with modest floods.
Astrøm, Anne Nordrehaug; Ekbäck, Gunnar; Ordell, Sven
2010-04-01
No studies have tested oral health-related quality of life models in dentate older adults across different populations. To test the factor structure of oral health outcomes within Gilbert's conceptual model among 65-year olds in Sweden and Norway. It was hypothesized that responses to 14 observed indicators could be explained by three correlated factors, symptom status, functional limitations and oral disadvantages, that each observed oral health indicator would associate more strongly with the factor it is supposed to measure than with competing factors and that the proposed 3-factor structure would possess satisfactory cross-national stability with 65-year olds in Norway and Sweden. In 2007, 6078 Swedish- and 4062 Norwegian adults borne in 1942 completed mailed questionnaires including oral symptoms, functional limitations and the eight item Oral Impacts on Daily Performances inventory. Model generation analysis was restricted to the Norwegian study group and the model achieved was tested without modifications in Swedish 65-year olds. A modified 3-factor solution with cross-loadings, improved the fit to the data compared with a 2-factor- and the initially proposed 3-factor model among the Norwegian [comparative fit index (CFI) = 0.97] and Swedish (CFI = 0.98) participants. All factor loadings for the modified 3-factor model were in the expected direction and were statistically significant at CR > 1. Multiple group confirmatory factor analyses, with Norwegian and Swedish data simultaneously revealed acceptable fit for the unconstrained model (CFI = 0.97), whereas unconstrained and constrained models were statistically significant different in nested model comparison. Within construct validity of Gilbert's model was supported with Norwegian and Swedish 65-year olds, indicating that the 14-item questionnaire reflected three constructs; symptom status, functional limitation and oral disadvantage. Measurement invariance was confirmed at the level of factor structure, suggesting that the 3-factor model is comparable to some extent across 65-year olds in Norway and Sweden.
Extensive validation of the pain disability index in 3 groups of patients with musculoskeletal pain.
Soer, Remko; Köke, Albère J A; Vroomen, Patrick C A J; Stegeman, Patrick; Smeets, Rob J E M; Coppes, Maarten H; Reneman, Michiel F
2013-04-20
A cross-sectional study design was performed. To validate the pain disability index (PDI) extensively in 3 groups of patients with musculoskeletal pain. The PDI is a widely used and studied instrument for disability related to various pain syndromes, although there is conflicting evidence concerning factor structure, test-retest reliability, and missing items. Additionally, an official translation of the Dutch language version has never been performed. For reliability, internal consistency, factor structure, test-retest reliability and measurement error were calculated. Validity was tested with hypothesized correlations with pain intensity, kinesiophobia, Rand-36 subscales, Depression, Roland-Morris Disability Questionnaire, Quality of Life, and Work Status. Structural validity was tested with independent backward translation and approval from the original authors. One hundred seventy-eight patients with acute back pain, 425 patients with chronic low back pain and 365 with widespread pain were included. Internal consistency of the PDI was good. One factor was identified with factor analyses. Test-retest reliability was good for the PDI (intraclass correlation coefficient, 0.76). Standard error of measurement was 6.5 points and smallest detectable change was 17.9 points. Little correlations between the PDI were observed with kinesiophobia and depression, fair correlations with pain intensity, work status, and vitality and moderate correlations with the Rand-36 subscales and the Roland-Morris Disability Questionnaire. The PDI-Dutch language version is internally consistent as a 1-factor structure, and test-retest reliable. Missing items seem high in sexual and professional items. Using the PDI as a 2-factor questionnaire has no additional value and is unreliable.
Lacham-Kaplan, Orly; Chy, Hun; Trounson, Alan
2006-02-01
Previous reports and the current study have found that germ cell precursor cells appear in embryoid bodies (EBs) formed from mouse embryonic stem cells as identified by positive expression of specific germ cell markers such as Oct-3/4, Mvh, c-kit, Stella, and DAZL. We hypothesized that if exposed to appropriate growth factors, the germ cell precursor cells within the EBs would differentiate into gametes. The source for growth factors used in the present study is conditioned medium collected from testicular cell cultures prepared from the testes of newborn males. Testes at this stage of development contain most growth factors required for the transformation of germ stem cells into differentiated gametes. When EBs were cultured in the conditioned medium, they developed into ovarian structures, which contained putative oocytes. The oocytes were surrounded by one to two layers of flattened cells and did not have a visible zona pellucida. However, oocyte-specific markers such as Fig-alpha and ZP3 were found expressed by the ovarian structures. The production of oocytes using this method is repeatable and reliable and may be applicable to other mammalian species, including the human.
Incidence and persistence of classical swine fever in free-ranging wild boar (Sus scrofa).
Rossi, S; Fromont, E; Pontier, D; Crucière, C; Hars, J; Barrat, J; Pacholek, X; Artois, M
2005-06-01
Although veterinary authorities aim to limit persistence of classical swine fever (CSF) in wild boar (Sus scrofa), to avoid potential transmission to pigs, factors influencing CSF transmission and persistence are not clearly understood. Here we analyse incidence and persistence in a CSF epidemic that occurred in the French Vosges Forest. Higher incidence was found in large forests compared to smaller isolated ones, being highest near the starting point of the epidemic, but poorly related to the local density. We hypothesize that the spatial and social structure of wild boar populations may be responsible for this variability of incidence over space. Persistence was highest near the starting point of the epidemic and where initial density was highest. We hypothesize that persistence was favoured by the abundance of young wild boar, itself encouraged by CSF. Our results allow us to propose management measures aimed at limiting CSF persistence.
Luyckx, Koen; Goossens, Luc; Soenens, Bart; Beyers, Wim
2006-06-01
A model of identity formation comprising four structural dimensions (Commitment Making, Identification with Commitment, Exploration in Depth, and Exploration in Breadth) was developed through confirmatory factor analysis. In a sample of 565 emerging adults, this model provided a better fit than did alternative two- and three-dimensional models, thereby validating the unpacking of both exploration and commitment. Regression analyses indicated that Commitment Making was significantly related to family context in accordance with hypotheses. Identification with Commitment and both exploration dimensions were significantly related to adjustment and family context, again in accordance with hypotheses. Identification with Commitment was positively related to positive adjustment indicators and negatively to depressive symptoms, whereas Exploration in Breadth was positively related to depressive symptoms and substance use. Exploration in Depth, on the other hand, was positively related to academic adjustment and negatively to substance use. Implications and suggestions for future research are discussed.
Kudel, Ian; Cotton, Sian; Leonard, Anthony C.; Tsevat, Joel; Ritchey, P. Neal
2011-01-01
A decade ago, an expert panel developed a framework for measuring spirituality/religion in health research (Brief Multidimensional Measure of Religiousness/Spirituality), but empirical testing of this framework has been limited. The purpose of this study was to determine whether responses to items across multiple measures assessing spirituality/religion by 450 patients with HIV replicate this model. We hypothesized a six-factor model underlying a collective of 56 items, but results of confirmatory factor analyses suggested eight dimensions: Meaning/Peace, Tangible Connection to the Divine, Positive Religious Coping, Love/Appreciation, Negative Religious Coping, Positive Congregational Support, Negative Congregational Support, and Cultural Practices. This study corroborates parts of the factor structure underlying the Brief Multidimensional Measure of Religiousness/Spirituality and some recent refinements of the original framework. PMID:21136166
Szaflarski, Magdalena; Kudel, Ian; Cotton, Sian; Leonard, Anthony C; Tsevat, Joel; Ritchey, P Neal
2012-12-01
A decade ago, an expert panel developed a framework for measuring spirituality/religion in health research (Brief Multidimensional Measure of Religiousness/Spirituality), but empirical testing of this framework has been limited. The purpose of this study was to determine whether responses to items across multiple measures assessing spirituality/religion by 450 patients with HIV replicate this model. We hypothesized a six-factor model underlying a collective of 56 items, but results of confirmatory factor analyses suggested eight dimensions: Meaning/Peace, Tangible Connection to the Divine, Positive Religious Coping, Love/Appreciation, Negative Religious Coping, Positive Congregational Support, Negative Congregational Support, and Cultural Practices. This study corroborates parts of the factor structure underlying the Brief Multidimensional Measure of Religiousness/Spirituality and some recent refinements of the original framework.
Portuguese Version of the Pain Beliefs and Perceptions Inventory: A Multicenter Validation Study.
Azevedo, Luís Filipe; Sampaio, Rute; Camila Dias, Cláudia; Romão, José; Lemos, Laurinda; Agualusa, Luís; Vaz-Serra, Sílvia; Patto, Teresa; Costa-Pereira, Altamiro; Castro-Lopes, José Manuel
2017-07-01
We aimed to perform the translation, cultural adaptation, and validation of the Pain Beliefs and Perceptions Inventory (PBPI) for the European Portuguese language and chronic pain population. This is a longitudinal multicenter validation study. A Portuguese version of the PBPI (PBPI-P) was created through a process of translation, back translation, and expert panel evaluation. The PBPI-P was administered to a total of 122 patients from 13 chronic pain clinics in Portugal, at baseline and after 7 days. Internal consistency and test-retest reliability were assessed by Cronbach's alpha (α) and intraclass correlation coefficient (ICC). Construct (convergent and discriminant) validity was assessed based on a set of previously developed theoretical hypotheses about interrelations between the PBPI-P and other measures. Exploratory and confirmatory factor analyses were performed to test the theoretical structure of the PBPI-P. The internal consistency and test-retest reliability coefficients for each respective subscale were α = 0.620 and ICC = 0.801 for mystery; α = 0.744 and ICC = 0.841 for permanence; α = 0.778 and ICC = 0.791 for constancy; and α = 0.764 and ICC = 0.881 for self-blame. Exploratory and confirmatory factor analysis revealed a four-factor structure (performance, constancy, self-blame, and mystery) that explained 63% of the variance. The construct validity of the PBPI-P was shown to be adequate, with more than 90% of the previously defined hypotheses regarding interrelations with other measures confirmed. The PBPI-P has been shown to be adequate and to have excellent reliability, internal consistency, and validity. It may contribute to a better pain assessment and is suitable for research and clinical use. © 2016 World Institute of Pain.
Relationships between bullying, school climate, and student risk behaviors.
Klein, Jennifer; Cornell, Dewey; Konold, Timothy
2012-09-01
This study examined whether characteristics of a positive school climate were associated with lower student risk behavior in a sample of 3,687 high school students who completed the School Climate Bullying Survey and questions about risk behavior from the Youth Risk Behavior Surveillance Survey (YRBS). Confirmatory factor analyses established fit for 20 items with three hypothesized school climate scales measuring (1) prevalence of bullying and teasing; (2) aggressive attitudes; and (3) student willingness to seek help. Structural equation modeling established the relationship of these measures with student reports of risk behavior. Multigroup analyses identified differential effects across gender and race. A positive school climate could be an important protective factor in preventing student risk behavior.
Tonsing, Kareen N; Tse, Samson; Tonsing, Jenny C
2016-02-01
Although migration itself may not compromise the mental health of immigrants, the acculturative process can involve highly stressful factors that are specific to immigrant and minority status. Using structural equation modeling, this study examined the relations between acculturation orientations, perceived discrimination, acculturative stress, and psychological distress among 229 Pakistani and 218 Nepalese migrants living in Hong Kong. Although the initial hypothesized model was not confirmed, a modified model with good fit indices showed that acculturation orientation mediated the relationships of perceived discrimination and acculturative stress with psychological distress. Of all the factors in the model, acculturative stress had the strongest association with psychological distress. © The Author(s) 2015.
Minnix, Jennifer A; Romero, Catherine; Joiner, Thomas E; Weinberg, Elizabeth F
2007-11-01
This study aims to investigate factors related to suicide in a unique clinical population with more chronic psychopathology than many outpatient samples. One hundred and five adult outpatients were included in the current study. We predicted that higher scores on the resolved plans and preparation (RPP) factor of the Beck Suicide Scale [Beck, A.T., Kovacs, M., Weissman, M., (1979). Assessment of suicidal intention: The scale for suicidal ideation. Journal of Consulting and Clinical Psychology 47, 343-352] would predict multiple attempter status even after accounting for co-morbid diagnoses and suicidal ideation (SI) factor scores. Additionally, we predicted that the scores on the RPP factor would decrease less over time than scores on the SI factor. Results were consistent with both hypotheses, suggesting that RPP factor scores were uniquely predictive of status as a multiple attempter and were more stable over time. Mental health diagnoses were rendered without the use of a structured interview and therefore no reliability data were collected.
Genetic and Environmental Architecture of Changes in Episodic Memory from Middle to Late Middle Age
Panizzon, Matthew S.; Neale, Michael C.; Docherty, Anna R.; Franz, Carol E.; Jacobson, Kristen C.; Toomey, Rosemary; Xian, Hong; Vasilopoulos, Terrie; Rana, Brinda K.; McKenzie, Ruth M.; Lyons, Michael J.; Kremen, William S.
2015-01-01
Episodic memory is a complex construct at both the phenotypic and genetic level. Ample evidence supports age-related cognitive stability and change being accounted for by general and domain-specific factors. We hypothesized that general and specific factors would underlie change even within this single cognitive domain. We examined six measures from three episodic memory tests in a narrow age cohort at middle and late middle age. The factor structure was invariant across occasions. At both timepoints two of three test-specific factors (story recall, design recall) had significant genetic influences independent of the general memory factor. Phenotypic stability was moderate to high, and primarily accounted for by genetic influences, except for one test-specific factor (list learning). Mean change over time was nonsignificant for one test-level factor; one declined; one improved. The results highlight the phenotypic and genetic complexity of memory and memory change, and shed light on an understudied period of life. PMID:25938244
Genetic and environmental architecture of changes in episodic memory from middle to late middle age.
Panizzon, Matthew S; Neale, Michael C; Docherty, Anna R; Franz, Carol E; Jacobson, Kristen C; Toomey, Rosemary; Xian, Hong; Vasilopoulos, Terrie; Rana, Brinda K; McKenzie, Ruth; Lyons, Michael J; Kremen, William S
2015-06-01
Episodic memory is a complex construct at both the phenotypic and genetic level. Ample evidence supports age-related cognitive stability and change being accounted for by general and domain-specific factors. We hypothesized that general and specific factors would underlie change even within this single cognitive domain. We examined 6 measures from 3 episodic memory tests in a narrow age cohort at middle and late middle age. The factor structure was invariant across occasions. At both timepoints 2 of 3 test-specific factors (story recall, design recall) had significant genetic influences independent of the general memory factor. Phenotypic stability was moderate to high, and primarily accounted for by genetic influences, except for 1 test-specific factor (list learning). Mean change over time was nonsignificant for 1 test-level factor; 1 declined; 1 improved. The results highlight the phenotypic and genetic complexity of memory and memory change, and shed light on an understudied period of life. (c) 2015 APA, all rights reserved.
Scale-dependent mechanisms of habitat selection for a migratory passerine: an experimental approach
Donovan, Therese M.; Cornell, Kerri L.
2010-01-01
Habitat selection theory predicts that individuals choose breeding habitats that maximize fitness returns on the basis of indirect environmental cues at multiple spatial scales. We performed a 3-year field experiment to evaluate five alternative hypotheses regarding whether individuals choose breeding territories in heterogeneous landscapes on the basis of (1) shrub cover within a site, (2) forest land-cover pattern surrounding a site, (3) conspecific song cues during prebreeding settlement periods, (4) a combination of these factors, and (5) interactions among these factors. We tested hypotheses with playbacks of conspecific song across a gradient of landscape pattern and shrub density and evaluated changes in territory occupancy patterns in a forest-nesting passerine, the Black-throated Blue Warbler (Dendroica caerulescens). Our results support the hypothesis that vegetation structure plays a primary role during presettlement periods in determining occupancy patterns in this species. Further, both occupancy rates and territory turnover were affected by an interaction between local shrub density and amount of forest in the surrounding landscape, but not by interactions between habitat cues and social cues. Although previous studies of this species in unfragmented landscapes found that social postbreeding song cues played a key role in determining territory settlement, our prebreeding playbacks were not associated with territory occupancy or turnover. Our results suggest that in heterogeneous landscapes during spring settlement, vegetation structure may be a more reliable signal of reproductive performance than the physical location of other individuals.
NASA Astrophysics Data System (ADS)
Wang, Mingyang; Zhang, Feifei; Song, Chao; Shi, Pengfei; Zhu, Jin
2016-07-01
Innovation in hypotheses is a key transformative driver for scientific development. The conventional centralized hypothesis formulation approach, where a dominant hypothesis is typically derived from a primary phenomenon, can, inevitably, impose restriction on the range of conceivable experiments and legitimate hypotheses, and ultimately impede understanding of the system of interest. We report herein the proposal of a decentralized approach for the formulation of hypotheses, through initial preconception-free phenomenon accumulation and subsequent reticular logical reasoning processes. The two-step approach can provide an unbiased, panoramic view of the system and as such should enable the generation of a set of more coherent and therefore plausible hypotheses. As a proof-of-concept demonstration of the utility of this open-ended approach, a hierarchical model has been developed for a prion self-assembled system, allowing insight into hitherto elusive static and dynamic features associated with this intriguing structure.
ERIC Educational Resources Information Center
Simons, Loretta N.
This study evaluated an hypothesized model of biopsychosocial factors that mediate the relationship between childhood abuse and substance abuse. A questionnaire packet consisting of self-report measures was administered to 160 drug dependent participants with and without co-occurring psychological disorders in residential, partial, and outpatient…
ERIC Educational Resources Information Center
Hazari, Zahra; Potvin, Geoff; Lock, Robynne M.; Lung, Florin; Sonnert, Gerhard; Sadler, Philip M.
2013-01-01
There are many hypotheses regarding factors that may encourage female students to pursue careers in the physical sciences. Using multivariate matching methods on national data drawn from the Persistence Research in Science and Engineering (PRiSE) project ("n" = 7505), we test the following five commonly held beliefs regarding what…
Biological pathways and genetic mechanisms involved in social functioning.
Ordoñana, Juan R; Bartels, Meike; Boomsma, Dorret I; Cella, David; Mosing, Miriam; Oliveira, Joao R; Patrick, Donald L; Veenhoven, Ruut; Wagner, Gert G; Sprangers, Mirjam A G
2013-08-01
To describe the major findings in the literature regarding associations between biological and genetic factors and social functioning, paying special attention to: (1) heritability studies on social functioning and related concepts; (2) hypothesized biological pathways and genetic variants that could be involved in social functioning, and (3) the implications of these results for quality-of-life research. A search of Web of Science and PubMed databases was conducted using combinations of the following keywords: genetics, twins, heritability, social functioning, social adjustment, social interaction, and social dysfunction. Variability in the definitions and measures of social functioning was extensive. Moderate to high heritability was reported for social functioning and related concepts, including prosocial behavior, loneliness, and extraversion. Disorders characterized by impairments in social functioning also show substantial heritability. Genetic variants hypothesized to be involved in social functioning are related to the network of brain structures and processes that are known to affect social cognition and behavior. Better knowledge and understanding about the impact of genetic factors on social functioning is needed to help us to attain a more comprehensive view of health-related quality-of-life (HRQOL) and will ultimately enhance our ability to identify those patients who are vulnerable to poor social functioning.
Conceptualization of an R&D Based Learning-to-Innovate Model for Science Education
NASA Astrophysics Data System (ADS)
Lai, Oiki Sylvia
The purpose of this research was to conceptualize an R & D based learning-to-innovate (LTI) model. The problem to be addressed was the lack of a theoretical L TI model, which would inform science pedagogy. The absorptive capacity (ACAP) lens was adopted to untangle the R & D LTI phenomenon into four learning processes: problem-solving via knowledge acquisition, incremental improvement via knowledge participation, scientific discovery via knowledge creation, and product design via knowledge productivity. The four knowledge factors were the latent factors and each factor had seven manifest elements as measured variables. The key objectives of the non experimental quantitative survey were to measure the relative importance of the identified elements and to explore the underlining structure of the variables. A questionnaire had been prepared, and was administered to more than 155 R & D professionals from four sectors - business, academic, government, and nonprofit. The results showed that every identified element was important to the R & D professionals, in terms of improving the related type of innovation. The most important elements were highlighted to serve as building blocks for elaboration. In search for patterns of the data matrix, exploratory factor analysis (EF A) was performed. Principal component analysis was the first phase of EF A to extract factors; while maximum likelihood estimation (MLE) was used to estimate the model. EF A yielded the finding of two aspects in each kind of knowledge. Logical names were assigned to represent the nature of the subsets: problem and knowledge under knowledge acquisition, planning and participation under knowledge participation, exploration and discovery under knowledge creation, and construction and invention under knowledge productivity. These two constructs, within each kind of knowledge, added structure to the vague R & D based LTI model. The research questions and hypotheses testing were addressed using correlation analysis. The alternative hypotheses that there were positive relationships between knowledge factors and their corresponding types of innovation were accepted. In-depth study of each process is recommended in both research and application. Experimental tests are needed, in order to ultimately present the LTI model to enhance the scientific knowledge absorptive capacity of the learners to facilitate their innovation performance.
Analyzing Human Behaviour Toward Food Waste in Qatar
NASA Astrophysics Data System (ADS)
A Hussain, Shaema Mohd Hassan
Food waste is a major issue in many countries due to the impact of waste on the environment and the cost of producing food and water. Food waste not only constitutes a hazard to the environment through the emission of greenhouse gases, but billions of dollars are also lost as a result of production, distribution and waste management costs. In view of this, this study examined factors that have potential to influence intent to waste food and food waste behavior among consumers in Qatar. The main objective of the study was to find a suitable model that explains food waste behavior in Qatar and compare it to an international model in order to understand region specific factors and try to replicate a hypothesized model of the causal effects of some factors (i.e., subjective norm, perceived behavioral control, and personal attitude) on intent to waste food and food waste behavior. Three research questions were developed and answers were provided by random selection of 139 respondents from the Qatar Foundation and Georgetown University Qatar databases gathered through a survey with 139 complete questionnaires in order to test the hypothesized model, which was created based on literature. The Structural Equation Modelling (SEM) approach was the main statistical tool of the investigation and was used to carry out the path analysis. The findings of the study revealed that factors, including, planning routine, Ramadan, gender task, and personal norm were strong predictors of intention to waste food and food waste behavior.
Translational Research in South Africa: Evaluating Implementation Quality Using a Factorial Design
Smith, Edward A.; Collins, Linda M.; Graham, John W.; Lai, Mary; Wegner, Lisa; Vergnani, Tania; Matthews, Catherine; Jacobs, Joachim
2012-01-01
Background HealthWise South Africa: Life Skills for Adolescents (HW) is an evidence-based substance use and sexual risk prevention program that emphasizes the positive use of leisure time. Since 2000, this program has evolved from pilot testing through an efficacy trial involving over 7,000 youth in the Cape Town area. Beginning in 2011, through 2015, we are undertaking a new study that expands HW to all schools in the Metro South Education District. Objective This paper describes a research study designed in partnership with our South African collaborators that examines three factors hypothesized to affect the quality and fidelity of HW implementation: enhanced teacher training; teacher support, structure and supervision; and enhanced school environment. Methods Teachers and students from 56 schools in the Cape Town area will participate in this study. Teacher observations are the primary means of collecting data on factors affecting implementation quality. These factors address the practical concerns of teachers and schools related to likelihood of use and cost-effectiveness, and are hypothesized to be “active ingredients” related to high-quality program implementation in real-world settings. An innovative factorial experimental design was chosen to enable estimation of the individual effect of each of the three factors. Results Because this paper describes the conceptualization of our study, results are not yet available. Conclusions The results of this study may have both substantive and methodological implications for advancing Type 2 translational research. PMID:22707870
Measuring Individual Differences in the Perfect Automation Schema.
Merritt, Stephanie M; Unnerstall, Jennifer L; Lee, Deborah; Huber, Kelli
2015-08-01
A self-report measure of the perfect automation schema (PAS) is developed and tested. Researchers have hypothesized that the extent to which users possess a PAS is associated with greater decreases in trust after users encounter automation errors. However, no measure of the PAS currently exists. We developed a self-report measure assessing two proposed PAS factors: high expectations and all-or-none thinking about automation performance. In two studies, participants responded to our PAS measure, interacted with imperfect automated aids, and reported trust. Each of the two PAS measure factors demonstrated fit to the hypothesized factor structure and convergent and discriminant validity when compared with propensity to trust machines and trust in a specific aid. However, the high expectations and all-or-none thinking scales showed low intercorrelations and differential relationships with outcomes, suggesting that they might best be considered two separate constructs rather than two subfactors of the PAS. All-or-none thinking had significant associations with decreases in trust following aid errors, whereas high expectations did not. Results therefore suggest that the all-or-none thinking scale may best represent the PAS construct. Our PAS measure (specifically, the all-or-none thinking scale) significantly predicted the severe trust decreases thought to be associated with high PAS. Further, it demonstrated acceptable psychometric properties across two samples. This measure may be used in future work to assess levels of PAS in users of automated systems in either research or applied settings. © 2015, Human Factors and Ergonomics Society.
Covariance hypotheses for LANDSAT data
NASA Technical Reports Server (NTRS)
Decell, H. P.; Peters, C.
1983-01-01
Two covariance hypotheses are considered for LANDSAT data acquired by sampling fields, one an autoregressive covariance structure and the other the hypothesis of exchangeability. A minimum entropy approximation of the first structure by the second is derived and shown to have desirable properties for incorporation into a mixture density estimation procedure. Results of a rough test of the exchangeability hypothesis are presented.
Game changer: the topology of creativity.
de Vaan, Mathijs; Stark, David; Vedres, Balazs
2015-01-01
This article examines the sociological factors that explain why some creative teams are able to produce game changers--cultural products that stand out as distinctive while also being critically recognized as outstanding. The authors build on work pointing to structural folding--the network property of a cohesive group whose membership overlaps with that of another cohesive group. They hypothesize that the effects of structural folding on game changing success are especially strong when overlapping groups are cognitively distant. Measuring social distance separately from cognitive distance and distinctiveness independently from critical acclaim, the authors test their hypothesis about structural folding and cognitive diversity by analyzing team reassembly for 12,422 video games and the career histories of 139,727 video game developers. When combined with cognitive distance, structural folding channels and mobilizes a productive tension of rules, roles, and codes that promotes successful innovation. In addition to serving as pipes and prisms, network ties are also the source of tools and tensions.
Comparative social grooming networks in captive chimpanzees and bonobos.
Rodrigues, Michelle A; Boeving, Emily R
2018-06-21
Despite similar dispersal patterns, models of Pan sociality emphasize sex differences in social bonding between the two species. Such disparities are attributed to hypothesized differences in environmental selective pressures that structure association patterns. However, recent research documents greater within-species variation in social bonds in both species. Here, we examine grooming networks in captive chimpanzees at the North Carolina Zoo, and captive bonobos at the Columbus Zoo. We hypothesized that male-female grooming relationships would be the strongest in both species, but that males and females of both species would not significantly differ between centrality, strength, or clustering. Via Mantel tests, we found that neither bonobos (t = - 0.070, r = - 0.009, two-tailed p = 0.942) nor chimpanzees (t = - 0.495, r = - 0.0939, two-tailed p = 0.6205) had significant differences in grooming between or within sexes. Neither species had significant sex differences in centrality, strength, or clustering. To account for idiosyncratic factors affecting grooming distribution, we examined the effect of origin, kinship, and group tenure on social network position. We found that wild-born bonobos exhibited greater eigenvector centrality (t = - 2.592, df = 9, p = 0.29) and strength (t = - 2.401; df = 9, p = 0.040), and group tenure was significantly correlated with strength (r = 0.608; N = 11, p - 0 = 0.47). None of these factors varied with social network position in chimpanzees. Our findings suggest that in captive settings, idiosyncratic factors related to individual history play a greater role in structuring social networks. Such variation may point to the behavioral flexibility inherent in fission-fusion networks, and mirror between-site variation found in wild chimpanzees. However, some idiosyncratic factors shaping captive networks may be an artifact of captivity.
Lanfranchi, A L; Rossin, M A; Timi, J T
2009-12-01
The structure and composition of parasite communities of Mullus argentinae were analysed under two alternative hypotheses in a sample of 75 specimens caught off Mar del Plata, Argentina (38 degrees 27'S, 57 degrees 90'W). The first, based on the dominance of trophically transmitted larval parasites of low host-specificity among fish species in the region, predicts that infracommunities will be random subsets of regionally available species. The second, based on previous studies on other mullids, predicts that infracommunities will be dominated by adult digeneans. The parasite fauna of goatfishes was mainly composed of endoparasites, with metacercariae of Prosorhynchus australis accounting for most individual parasites and greatly affecting infracommunity descriptors. Its importance was reinforced by the low number of trophically transmitted larval parasites. Both hypotheses were refuted; parasite communities were not dominated either by trophically transmitted larval parasites of low host-specificity or by adult digeneans. Prosorhynchus australis was the only species displaying any degree of phylogenetic specificity. Therefore, the influence of phylogenetic factors seems to exceed that of ecological ones in determining the observed structure of infracommunities. However, it is precisely host ecology that allows P. australis to become the determinant of infracommunity structure by constraining the acquisition of other parasites. Studies aiming to determine the relative importance of evolutionary and ecological processes as structuring forces of parasite communities should take into account not only the identity and specificity of their component parasites, but also their availability in the compound community.
Thaler, Nicholas S; Allen, Daniel N; Sutton, Griffin P; Vertinski, Mary; Ringdahl, Erik N
2013-12-01
While it is well-established that patients with schizophrenia and bipolar disorder exhibit deficits in social cognition, few studies have separately examined bipolar disorder with and without psychotic features. The current study addressed this gap by comparing patients with bipolar disorder with (BD+) and without (BD-) psychotic features, patients with schizophrenia (SZ), and healthy controls (NC) across social cognitive measures. Principal factor analysis on five social cognition tasks extracted a two-factor structure comprised of social/emotional processing and theory of mind. Factor scores were compared among the four groups. Results identified differential patterns of impairment between the BD+ and BD- group on the social/emotional processing factor while all clinical groups performed poorer than controls on the theory of mind factor. This provides evidence that a history of psychosis should be taken into account while evaluating social cognition in patients with bipolar disorder and also raises hypotheses about the relationship between social cognition and psychosis. Copyright © 2013 Elsevier Ltd. All rights reserved.
Marshall, Grant N; Sherbourne, Cathy D; Meredith, Lisa S; Camp, Patti; Hays, Ron D
2003-04-01
The structure of self-reported symptoms representative of the tripartite model was examined using data drawn from the Medical Outcomes Study (Tarlov et al., 1989). Participants were persons who had been diagnosed 48 months previously as suffering from either depression (N = 315) or hypertension (N = 403). Results of confirmatory factor analyses were broadly consistent with the tripartite model (L. A. Clark & Watson, 1991). Factors emerged corresponding to each of the 3 posited first-order dimensions of negative affect, positive affect, and physiologic arousal. Nonetheless, some discrepancies were found between the observed data and the hypothesized tripartite model. First, the obtained physiologic arousal factor was best viewed as reflecting nonspecific somatic distress rather than physiologic arousal. Finally, although differentiable in the strictest statistical sense, all three domains were significantly correlated (.36 to.86, absolute value). In particular, contrary to the tripartite model, positive and negative affect covaried markedly (-.81 to -.86). Findings raise issues concerning the utility of the tripartite model as a heuristic framework for enhancing understanding of individual differences in normal mood as well as mood disorders.
Chen, Yuan; Wong, Lena L. N.; Zhu, Shufeng; Xi, Xin
2015-01-01
Objective To examine the direct and indirect effects of demographical factors on speech perception and vocabulary outcomes of Mandarin-speaking children with cochlear implants (CIs). Methods 115 participants implanted before the age of 5 and who had used CI before 1 to 3 years were evaluated using a battery of speech perception and vocabulary tests. Structural equation modeling was used to test the hypotheses proposed. Results Early implantation significantly contributed to speech perception outcomes while having undergone a hearing aid trial (HAT) before implantation, maternal educational level (MEL), and having undergone universal newborn hearing screening (UNHS) before implantation had indirect effects on speech perception outcomes via their effects on age at implantation. In addition, both age at implantation and MEL had direct and indirect effects on vocabulary skills, while UNHS and HAT had indirect effects on vocabulary outcomes via their effects on age at implantation. Conclusion A number of factors had indirect and direct effects on speech perception and vocabulary outcomes in Mandarin-speaking children with CIs and these factors were not necessarily identical to those reported among their English-speaking counterparts. PMID:26348360
Handren, Lindsay; Crano, William D.
2018-01-01
Culturally, people tend to abstain from alcohol intake during the weekdays and wait to consume in greater frequency and quantity during the weekends. The current research sought to empirically justify the days representing weekday versus weekend alcohol consumption. In study 1 (N = 419), item response theory was applied to a two-parameter (difficulty and discrimination) model that evaluated the days of drinking (frequency) during the typical 7-day week. Item characteristic curves were most similar for Monday, Tuesday, and Wednesday (prototypical weekday) and for Friday and Saturday (prototypical weekend). Thursday and Sunday, however, exhibited item characteristics that bordered the properties of weekday and weekend consumption. In study 2 (N = 403), confirmatory factor analysis was applied to test six hypothesized measurement structures representing drinks per day (quantity) during the typical week. The measurement model producing the strongest fit indices was a correlated two-factor structure involving separate weekday and weekend factors that permitted Thursday and Sunday to double load on both dimensions. The proper conceptualization and accurate measurement of the days demarcating the normative boundaries of “dry” weekdays and “wet” weekends are imperative to inform research and prevention efforts targeting temporal alcohol intake patterns. PMID:27488456
Lac, Andrew; Handren, Lindsay; Crano, William D
2016-10-01
Culturally, people tend to abstain from alcohol intake during the weekdays and wait to consume in greater frequency and quantity during the weekends. The current research sought to empirically justify the days representing weekday versus weekend alcohol consumption. In study 1 (N = 419), item response theory was applied to a two-parameter (difficulty and discrimination) model that evaluated the days of drinking (frequency) during the typical 7-day week. Item characteristic curves were most similar for Monday, Tuesday, and Wednesday (prototypical weekday) and for Friday and Saturday (prototypical weekend). Thursday and Sunday, however, exhibited item characteristics that bordered the properties of weekday and weekend consumption. In study 2 (N = 403), confirmatory factor analysis was applied to test six hypothesized measurement structures representing drinks per day (quantity) during the typical week. The measurement model producing the strongest fit indices was a correlated two-factor structure involving separate weekday and weekend factors that permitted Thursday and Sunday to double load on both dimensions. The proper conceptualization and accurate measurement of the days demarcating the normative boundaries of "dry" weekdays and "wet" weekends are imperative to inform research and prevention efforts targeting temporal alcohol intake patterns.
Mobile computing acceptance factors in the healthcare industry: a structural equation model.
Wu, Jen-Her; Wang, Shu-Ching; Lin, Li-Min
2007-01-01
This paper presents a revised technology acceptance model to examine what determines mobile healthcare systems (MHS) acceptance by healthcare professionals. Conformation factor analysis was performed to test the reliability and validity of the measurement model. The structural equation modeling technique was used to evaluate the causal model. The results indicated that compatibility, perceived usefulness and perceived ease of use significantly affected healthcare professional behavioral intent. MHS self-efficacy had strong indirect impact on healthcare professional behavioral intent through the mediators of perceived usefulness and perceived ease of use. Yet, the hypotheses for technical support and training effects on the perceived usefulness and perceived ease of use were not supported. This paper provides initial insights into factors that are likely to be significant antecedents of planning and implementing mobile healthcare to enhance professionals' MHS acceptance. The proposed model variables explained 70% of the variance in behavioral intention to use MHS; further study is needed to explore extra significant antecedents of new IT/IS acceptance for mobile healthcare. Such as privacy and security issue, system and information quality, limitations of mobile devices; the above may be other interesting factors for implementing mobile healthcare and could be conducted by qualitative research.
Ramirez, Kelly S; Knight, Christopher G; de Hollander, Mattias; Brearley, Francis Q; Constantinides, Bede; Cotton, Anne; Creer, Si; Crowther, Thomas W; Davison, John; Delgado-Baquerizo, Manuel; Dorrepaal, Ellen; Elliott, David R; Fox, Graeme; Griffiths, Robert I; Hale, Chris; Hartman, Kyle; Houlden, Ashley; Jones, David L; Krab, Eveline J; Maestre, Fernando T; McGuire, Krista L; Monteux, Sylvain; Orr, Caroline H; van der Putten, Wim H; Roberts, Ian S; Robinson, David A; Rocca, Jennifer D; Rowntree, Jennifer; Schlaeppi, Klaus; Shepherd, Matthew; Singh, Brajesh K; Straathof, Angela L; Bhatnagar, Jennifer M; Thion, Cécile; van der Heijden, Marcel G A; de Vries, Franciska T
2018-02-01
The emergence of high-throughput DNA sequencing methods provides unprecedented opportunities to further unravel bacterial biodiversity and its worldwide role from human health to ecosystem functioning. However, despite the abundance of sequencing studies, combining data from multiple individual studies to address macroecological questions of bacterial diversity remains methodically challenging and plagued with biases. Here, using a machine-learning approach that accounts for differences among studies and complex interactions among taxa, we merge 30 independent bacterial data sets comprising 1,998 soil samples from 21 countries. Whereas previous meta-analysis efforts have focused on bacterial diversity measures or abundances of major taxa, we show that disparate amplicon sequence data can be combined at the taxonomy-based level to assess bacterial community structure. We find that rarer taxa are more important for structuring soil communities than abundant taxa, and that these rarer taxa are better predictors of community structure than environmental factors, which are often confounded across studies. We conclude that combining data from independent studies can be used to explore bacterial community dynamics, identify potential 'indicator' taxa with an important role in structuring communities, and propose hypotheses on the factors that shape bacterial biogeography that have been overlooked in the past.
Dutch version of the Fear of Pain Questionnaire for adolescents with chronic pain.
Dekker, Carolien; Bastiaenen, Caroline H G; de Vries, Janneke E; Simons, Laura E; Goossens, Mariëlle E J B; Verbunt, Jeanine A M C F
2018-06-01
Fear of pain is important in the development and maintenance of chronic pain. The Fear of Pain Questionnaire-Child version has been developed to assess pain related fear in children and adolescents. Translating the original questionnaire into Dutch, and investigating internal consistency and construct validity to enable use in the Dutch pain rehabilitation setting for treatment and research. Cross-sectional validation study: After forward and back translation of the FOPQ-C, adolescents (11-22 years old) with chronic musculoskeletal pain completed an assessment containing the Dutch Fear of Pain Questionnaire, and questionnaires about demographics, pain catastrophizing, functional disability, and pain intensity. Internal consistency and construct validity were evaluated through exploratory factor analysis (principal axis factoring with oblique rotation) and hypotheses testing using pain catastrophizing, functional disability, and pain intensity as comparative constructs. Eighty-six adolescents completed the assessment. Exploratory factor analysis resulted in a two-factor structure, explaining 43% of the variance. Internal consistency was strong (Cronbach's α = 0.92 total scale, α = 0.88 factor 1, and α = .86 factor 2). Five out of 6 hypotheses were confirmed. The Dutch version demonstrated good internal consistency and good construct validity in a population of adolescents with chronic musculoskeletal pain. Implications for rehabilitation The Fear of Pain Questionnaire-Child version was developed to measure fear of pain and avoidance in children and adolescents with chronic pain. Identification of fear of pain and activities that are being avoided are important during screening and assessment of the adolescent for chronic pain rehabilitation treatment. The presence of fear of pain and/or avoidance behavior is important information to shape and target multidisciplinary rehabilitation treatment.
Austin, Jane E.; Slattery, Stuart; Clark, Robert G.
2014-01-01
There are 30 threatened or endangered species of waterfowl worldwide, and several sub-populations are also threatened. Some of these species occur in North America, and others there are also of conservation concern due to declining population trends and their importance to hunters. Here we review conservation initiatives being undertaken for several of these latter species, along with conservation measures in place in Europe, to seek common themes and approaches that could be useful in developing broad conservation guidelines. While focal species may vary in their life histories, population threats and geopolitical context, most conservation efforts have used a systematic approach to understand factors limiting populations and o identify possible management or policy actions. This approach generally includes a priori identification of plausible hypotheses about population declines or status, incorporation of hypotheses into conceptual or quantitative planning models, and the use of some form of structured decision making and adaptive management to develop and implement conservation actions in the face of many uncertainties. A climate of collaboration among jurisdictions sharing these birds is important to the success of a conservation or management programme. The structured conservation approach exemplified herein provides an opportunity to involve stakeholders at all planning stages, allows for all views to be examined and incorporated into model structures, and yields a format for improved communication, cooperation and learning, which may ultimately be one of the greatest benefits of this strategy.
Bacterial phylogeny structures soil resistomes across habitats
Forsberg, Kevin J.; Patel, Sanket; Gibson, Molly K.; Lauber, Christian L.; Knight, Rob; Fierer, Noah; Dantas, Gautam
2014-01-01
Summary Ancient and diverse antibiotic resistance genes (ARGs) have previously been identified from soil1–3, including genes identical to those in human pathogens4. Despite the apparent overlap between soil and clinical resistomes4–6, factors influencing ARG composition in soil and their movement between genomes and habitats remain largely unknown3. General metagenome functions often correlate with the underlying structure of bacterial communities7–12. However, ARGs are hypothesized to be highly mobile4,5,13, prompting speculation that resistomes may not correlate with phylogenetic signatures or ecological divisions13,14. To investigate these relationships, we performed functional metagenomic selections for resistance to 18 antibiotics from 18 agricultural and grassland soils. The 2895 ARGs we discovered were predominantly novel, and represent all major resistance mechanisms15. We demonstrate that distinct soil types harbor distinct resistomes, and that nitrogen fertilizer amendments strongly influenced soil ARG content. Resistome composition also correlated with microbial phylogenetic and taxonomic structure, both across and within soil types. Consistent with this strong correlation, mobility elements syntenic with ARGs were rare in soil compared to sequenced pathogens, suggesting that ARGs in the soil may not transfer between bacteria as readily as is observed in the clinic. Together, our results indicate that bacterial community composition is the primary determinant of soil ARG content, challenging previous hypotheses that horizontal gene transfer effectively decouples resistomes from phylogeny13,14. PMID:24847883
A Study of Individual Responses to Bullying as a Function of Teacher Burnout
ERIC Educational Resources Information Center
Rice, Wanda J.
2013-01-01
It is hypothesized that factors related to teacher burnout influence responses to bullying behaviors. This study hypothesizes that teachers with a higher degree of burnout are less likely to respond to bullying behaviors and it further hypothesizes that those with greater years of teaching are less likely to respond to bullying behaviors. Of…
Listening, Watching, and Reading: The Structure and Correlates of Entertainment Preferences
Rentfrow, Peter J.; Goldberg, Lewis R.; Zilca, Ran
2010-01-01
People spend considerable amounts of time and money listening to music, watching TV and movies, and reading books and magazines, yet almost no attention in psychology has been devoted to understanding individual differences in preferences for such entertainment. The present research was designed to examine the structure and correlates of entertainment genre preferences. Analyses of the genre preferences of over 3,000 individuals revealed a remarkably clear factor structure. Using multiple samples, methods, and geographic regions, data converged to reveal five entertainment-preference dimensions: Communal, Aesthetic, Dark, Thrilling, and Cerebral. Preferences for these entertainment dimensions were uniquely related to demographics and personality traits. Results also indicated that personality accounted for significant proportions of variance in entertainment preferences over and above demographics. The results provide a foundation for developing and testing hypotheses about the psychology of entertainment preferences. PMID:20649744
McDonough, Christine M; Jette, Alan M; Ni, Pengsheng; Bogusz, Kara; Marfeo, Elizabeth E; Brandt, Diane E; Chan, Leighton; Meterko, Mark; Haley, Stephen M; Rasch, Elizabeth K
2013-09-01
To build a comprehensive item pool representing work-relevant physical functioning and to test the factor structure of the item pool. These developmental steps represent initial outcomes of a broader project to develop instruments for the assessment of function within the context of Social Security Administration (SSA) disability programs. Comprehensive literature review; gap analysis; item generation with expert panel input; stakeholder interviews; cognitive interviews; cross-sectional survey administration; and exploratory and confirmatory factor analyses to assess item pool structure. In-person and semistructured interviews and Internet and telephone surveys. Sample of SSA claimants (n=1017) and a normative sample of adults from the U.S. general population (n=999). Not applicable. Model fit statistics. The final item pool consisted of 139 items. Within the claimant sample, 58.7% were white; 31.8% were black; 46.6% were women; and the mean age was 49.7 years. Initial factor analyses revealed a 4-factor solution, which included more items and allowed separate characterization of: (1) changing and maintaining body position, (2) whole body mobility, (3) upper body function, and (4) upper extremity fine motor. The final 4-factor model included 91 items. Confirmatory factor analyses for the 4-factor models for the claimant and the normative samples demonstrated very good fit. Fit statistics for claimant and normative samples, respectively, were: Comparative Fit Index=.93 and .98; Tucker-Lewis Index=.92 and .98; and root mean square error approximation=.05 and .04. The factor structure of the physical function item pool closely resembled the hypothesized content model. The 4 scales relevant to work activities offer promise for providing reliable information about claimant physical functioning relevant to work disability. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Hedonic Homeostatic Dysregulation as a Driver of Drug-Seeking Behavior
Koob, George F.
2009-01-01
Drug addiction can be defined by a compulsion to seek and take drug and loss of control in limiting intake, and the excessive drug taking derives from multiple motivational mechanisms. One such mechanism is the emergence of a negative emotional state when access to the drug is prevented, reflecting hedonic homeostatic dysregulation. Excessive drug taking then results in part via the construct of negative reinforcement. The negative emotional state that drives such negative reinforcement is hypothesized to derive from dysregulation of key neurochemical elements involved in reward and stress within basal forebrain structures, including the ventral striatum and extended amygdala. Specific neurochemical elements in these structures include not only decreases in reward neurotransmission, such as decreases in dopamine and opioid peptide function in the ventral striatum, but also recruitment of brain stress systems, such as corticotropin-releasing factor (CRF), in the extended amygdala. Chronic exposure or extended access to self-administration of all major drugs of abuse produces during abstinence increases in reward thresholds, increases in aversive anxiety-like responses, increases in extracellular levels of CRF in the central nucleus of the amygdala, and increases in drug self-administration. CRF receptor antagonists block excessive drug intake produced by dependence. A combination of decreased reward system function and increased brain stress response system function is hypothesized to be responsible for hedonic homeostatic dysregulation that drives drug seeking behavior in dependence. Such hedonic dysregulation is hypothesized to extend into protracted abstinence to provide a residual negative emotional state that enhances the salience of cues eliciting drug seeking and relapse. PMID:20054425
Huff-Lonergan, E; Lonergan, S M
2007-11-01
The aim of this review was to summarize some of the most important and novel hypotheses regarding the development of water-holding capacity in pork. Among the key factors that determine water-holding capacity are rate and extent of pH decline and the structure of the muscle and the muscle cell itself. However, there have been numerous reviews on the importance of pH yet relatively few on the concept of how muscle cell structure influences the ability of the postmortem cell to maintain water/moisture. Recent advances in the ability of scientists to monitor the movement of water within the cell and within the muscle and to monitor protein degradation have led to new hypotheses regarding the development of drip or purge from fresh meat. One of the more novel and promising hypotheses that has surfaced recently is that alterations in the architecture of the cell may govern the retention/loss of moisture from the muscle cell and ultimately the muscle. The degradation of cytoskeletal and intermediate filament proteins (like desmin) early postmortem may release constraints within the cell that limit the space available for water/fluid that has been forced from the myofibril during rigour. Conversely, degradation of some membrane proteins (like integrin) could actually contribute to the formation of drip channels and thus might actually improve the ability of moisture to 'escape' from the muscle cell. Thus, water-holding capacity in fresh meat is associated with specific changes that occur in early postmortem muscle.
Physical Education Students' Ownership, Empowerment, and Satisfaction With PE and Physical Activity.
Moore, E Whitney G; Fry, Mary D
2017-12-01
Individuals experiencing a highly caring, task-involving, and low ego-involving exercise climate have reported greater ownership in exercise class and empowerment to exercise in general. This study examined the relationship between ownership and empowerment in exercise, with 2 context-specific outcomes, satisfaction with physical education (PE) and physical activity, respectively. Given the mission of PE to foster individuals' lifelong physical activity habit, the perceptions of high school students were collected for this study. Ownership in exercise was hypothesized to be significantly, positively correlated with students reporting satisfaction in PE more than their satisfaction in physical activity, whereas empowerment in exercise was hypothesized to be more strongly, positively correlated with students' physical activity satisfaction. A second purpose of this study was to test the measurement quality of the updated Empowerment in Exercise Scale (EES; now 13 items). High school students (N = 502, 43% female) in a Midwestern U.S. school district completed a survey. Confirmatory factor analysis supported the internal measurement structure of the EES (λ = .62-.91; McDonald's omega = .89) across student gender (strong invariance). Additionally, the structural equation modeling analysis revealed only 1 parameter moderated by the students' gender (latent mean of ownership). The hypotheses were supported, such that ownership in exercise was more strongly correlated with PE satisfaction (r = .87) and empowerment in exercise had a stronger correlation with physical activity satisfaction (r = .92). These results support the beneficial effect a satisfying experience in PE can have on students' satisfaction with physical activity outside of school.
Does the Assessment of Recovery Capital scale reflect a single or multiple domains?
Arndt, Stephan; Sahker, Ethan; Hedden, Suzy
2017-01-01
The goal of this study was to determine whether the 50-item Assessment of Recovery Capital scale represents a single general measure or whether multiple domains might be psychometrically useful for research or clinical applications. Data are from a cross-sectional de-identified existing program evaluation information data set with 1,138 clients entering substance use disorder treatment. Principal components and iterated factor analysis were used on the domain scores. Multiple group factor analysis provided a quasi-confirmatory factor analysis. The solution accounted for 75.24% of the total variance, suggesting that 10 factors provide a reasonably good fit. However, Tucker's congruence coefficients between the factor structure and defining weights (0.41-0.52) suggested a poor fit to the hypothesized 10-domain structure. Principal components of the 10-domain scores yielded one factor whose eigenvalue was greater than one (5.93), accounting for 75.8% of the common variance. A few domains had perceptible but small unique variance components suggesting that a few of the domains may warrant enrichment. Our findings suggest that there is one general factor, with a caveat. Using the 10 measures inflates the chance for Type I errors. Using one general measure avoids this issue, is simple to interpret, and could reduce the number of items. However, those seeking to maximally predict later recovery success may need to use the full instrument and all 10 domains.
Evidence of structural invariance across three groups of Meehlian schizotypes
Chan, Raymond CK; Gooding, Diane C; Shi, Hai-song; Geng, Fu-lei; Xie, Dong-jie; Yang, Zhuo-Ya; Liu, Wen-hua; Wang, Yi; Yan, Chao; Shi, Chuan; Lui, Simon SY; Cheung, Eric FC
2016-01-01
According to Meehl’s model of schizotypy, there is a latent personality organization associated with the diathesis for schizophrenia that can be identified in several ways. We sought to examine the structural invariance of four Chapman psychosis–proneness scales (CPPS) across three groups of putative schizotypes, namely, clinically-, biologically-, and psychometrically-identified schizotypes. We examined the factor structure of the Perceptual Aberration (PER), Magical Ideation (MIS), Revised Social Anhedonia (RSAS), and Revised Physical Anhedonia (RPAS) scales in 196 schizophrenia patients, 197 non-psychotic first-degree relatives, and 1,724 non-clinical young adults. The confirmatory factor analyses indicated that the best-fitting model was one in which there is a two-factor model with negative schizotypy (RSAS and RPAS) and positive schizotypy (PER and MIS). All three samples fit the model well, with Comparative Fit Indices>0.95 and Tucker Lewis Indices>0.90. The root mean square error of approximations were all small (P values⩽0.01). We also observed that for both anhedonia scales, the groups’ mean scale scores varied in the hypothesized direction, as predicted by Meehl’s model of schizotypy. All three Chinese samples, namely, the patients (clinical schizotypes), relatives (biologically-identified schizotypes), and non-clinical young adults (containing psychometrically-identified schizotypes) showed the same factorial structure. This finding supports the suitability of the CPPS for cross-cultural and/or genetic investigations of schizotypy. PMID:27336057
Horn, Sebastian; Hempel, Stefan; Verbruggen, Erik; Rillig, Matthias C; Caruso, Tancredi
2017-01-01
Arbuscular mycorrhizal fungi (AMF) are crucial to plants and vice versa, but little is known about the factors linking the community structure of the two groups. We investigated the association between AMF and the plant community structure in the nearest neighborhood of Festuca brevipila in a semiarid grassland with steep environmental gradients, using high-throughput sequencing of the Glomeromycotina (former Glomeromycota). We focused on the Passenger, Driver and Habitat hypotheses: (i) plant communities drive AMF (passenger); (ii) AMF communities drive the plants (driver); (iii) the environment shapes both communities causing covariation. The null hypothesis is that the two assemblages are independent and this study offers a spatially explicit novel test of it in the field at multiple, small scales. The AMF community consisted of 71 operational taxonomic units, the plant community of 47 species. Spatial distance and spatial variation in the environment were the main determinants of the AMF community. The structure of the plant community around the focal plant was a poor predictor of AMF communities, also in terms of phylogenetic community structure. Some evidence supports the passenger hypothesis, but the relative roles of the factors structuring the two groups clearly differed, leading to an apparent decoupling of the two assemblages at the relatively small scale of this study. Community phylogenetic structure in AMF suggests an important role of within-assemblage interactions. PMID:28244977
Horn, Sebastian; Hempel, Stefan; Verbruggen, Erik; Rillig, Matthias C; Caruso, Tancredi
2017-06-01
Arbuscular mycorrhizal fungi (AMF) are crucial to plants and vice versa, but little is known about the factors linking the community structure of the two groups. We investigated the association between AMF and the plant community structure in the nearest neighborhood of Festuca brevipila in a semiarid grassland with steep environmental gradients, using high-throughput sequencing of the Glomeromycotina (former Glomeromycota). We focused on the Passenger, Driver and Habitat hypotheses: (i) plant communities drive AMF (passenger); (ii) AMF communities drive the plants (driver); (iii) the environment shapes both communities causing covariation. The null hypothesis is that the two assemblages are independent and this study offers a spatially explicit novel test of it in the field at multiple, small scales. The AMF community consisted of 71 operational taxonomic units, the plant community of 47 species. Spatial distance and spatial variation in the environment were the main determinants of the AMF community. The structure of the plant community around the focal plant was a poor predictor of AMF communities, also in terms of phylogenetic community structure. Some evidence supports the passenger hypothesis, but the relative roles of the factors structuring the two groups clearly differed, leading to an apparent decoupling of the two assemblages at the relatively small scale of this study. Community phylogenetic structure in AMF suggests an important role of within-assemblage interactions.
Eisenberg, Daniel P; Aniskin, Dmitry B; White, Leonard; Stein, Judith A; Harvey, Philip D; Galynker, Igor I
2009-01-01
The emerging dimensional approach to classification and treatment of psychiatric disorders calls for better understanding of diagnosis-related variations in psychiatric syndromes and for proper validation of psychometric scales used for the evaluation of those syndromes. This study tested the hypothesis that negative and depressive syndromes as measured by the Positive and Negative Syndrome Scale (PANSS) are consistent across different diagnoses. We administered the PANSS to subjects with schizophrenia (n = 305), organic brain disease (OBD, n = 66) and major depressive disorder (MDD, n = 75). Confirmatory factor analysis (CFA) was used to establish if the PANSS items for negative symptoms and for depression fit the hypothesized factor structure and if the item factor loadings were similar among the diagnostic groups. The negative and depressive symptom subscales fit well according to a variety of fit indexes for all groups individually after some modest model modification. However, multisample modeling procedures indicated that the pattern of factor loadings was significantly different among the groups in most cases. The results of this study indicate diagnosis-related variations in the negative and depressive syndrome dimensions in schizophrenia, OBD and MDD. These results also validate limited use of the PANSS for evaluation of negative and depressive syndromes in disorders other than schizophrenia. Larger studies are warranted to further evaluate clinical and nosologic significance of diagnostic categories, dimensions and structures of psychiatric syndromes. 2009 S. Karger AG, Basel.
Stanley, Thomas R.; Newmark, William D.
2015-01-01
Most tropical insectivorous birds, unlike their temperate counterparts, hold and defend a feeding and breeding territory year-around. However, our understanding of ecological factors influencing territory selection and size in tropical insectivores is limited. Here we examine three prominent hypotheses relating food abundance, food dispersion (spatial arrangement of food items), and habitat structure to territoriality in the Usambara Thrush Turdus roehli. We first compared leaf-litter macro-invertebrate abundance and dispersion, and habitat structure between territories and random sites. We then examined the relation between these same ecological factors and territory size. Invertebrate abundance and dispersion were sparsely and evenly distributed across our study system and did not vary between territories and random sites. In contrast, habitat structure did vary between territories and random sites indicating the Usambara Thrush selects territories with open understorey and closed overstorey habitat. Invertebrate abundance and dispersion within territories of the Usambara Thrush were not associated with habitat structure. We believe the most likely explanation for the Usambara Thrush’s preference for open understorey and closed overstorey habitat relates to foraging behavior. Using information-theoretic model selection we found that invertebrate abundance was the highest-ranked predictor of territory size and was inversely related, consistent with food value theory of territoriality.
Deciphering structural and temporal interplays during the architectural development of mango trees.
Dambreville, Anaëlle; Lauri, Pierre-Éric; Trottier, Catherine; Guédon, Yann; Normand, Frédéric
2013-05-01
Plant architecture is commonly defined by the adjacency of organs within the structure and their properties. Few studies consider the effect of endogenous temporal factors, namely phenological factors, on the establishment of plant architecture. This study hypothesized that, in addition to the effect of environmental factors, the observed plant architecture results from both endogenous structural and temporal components, and their interplays. Mango tree, which is characterized by strong phenological asynchronisms within and between trees and by repeated vegetative and reproductive flushes during a growing cycle, was chosen as a plant model. During two consecutive growing cycles, this study described vegetative and reproductive development of 20 trees submitted to the same environmental conditions. Four mango cultivars were considered to assess possible cultivar-specific patterns. Integrative vegetative and reproductive development models incorporating generalized linear models as components were built. These models described the occurrence, intensity, and timing of vegetative and reproductive development at the growth unit scale. This study showed significant interplays between structural and temporal components of plant architectural development at two temporal scales. Within a growing cycle, earliness of bud burst was highly and positively related to earliness of vegetative development and flowering. Between growing cycles, flowering growth units delayed vegetative development compared to growth units that did not flower. These interplays explained how vegetative and reproductive phenological asynchronisms within and between trees were generated and maintained. It is suggested that causation networks involving structural and temporal components may give rise to contrasted tree architectures.
A framework for the etiology of running-related injuries.
Bertelsen, M L; Hulme, A; Petersen, J; Brund, R K; Sørensen, H; Finch, C F; Parner, E T; Nielsen, R O
2017-11-01
The etiology of running-related injury is important to consider as the effectiveness of a given running-related injury prevention intervention is dependent on whether etiologic factors are readily modifiable and consistent with a biologically plausible causal mechanism. Therefore, the purpose of the present article was to present an evidence-informed conceptual framework outlining the multifactorial nature of running-related injury etiology. In the framework, four mutually exclusive parts are presented: (a) Structure-specific capacity when entering a running session; (b) structure-specific cumulative load per running session; (c) reduction in the structure-specific capacity during a running session; and (d) exceeding the structure-specific capacity. The framework can then be used to inform the design of future running-related injury prevention studies, including the formation of research questions and hypotheses, as well as the monitoring of participation-related and non-participation-related exposures. In addition, future research applications should focus on addressing how changes in one or more exposures influence the risk of running-related injury. This necessitates the investigation of how different factors affect the structure-specific load and/or the load capacity, and the dose-response relationship between running participation and injury risk. Ultimately, this direction allows researchers to move beyond traditional risk factor identification to produce research findings that are not only reliably reported in terms of the observed cause-effect association, but also translatable in practice. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Towards self-learning based hypotheses generation in biomedical text domain.
Gopalakrishnan, Vishrawas; Jha, Kishlay; Xun, Guangxu; Ngo, Hung Q; Zhang, Aidong
2018-06-15
The overwhelming amount of research articles in the domain of bio-medicine might cause important connections to remain unnoticed. Literature Based Discovery is a sub-field within biomedical text mining that peruses these articles to formulate high confident hypotheses on possible connections between medical concepts. Although many alternate methodologies have been proposed over the last decade, they still suffer from scalability issues. The primary reason, apart from the dense inter-connections between biological concepts, is the absence of information on the factors that lead to the edge-formation. In this work, we formulate this problem as a collaborative filtering task and leverage a relatively new concept of word-vectors to learn and mimic the implicit edge-formation process. Along with single-class classifier, we prune the search-space of redundant and irrelevant hypotheses to increase the efficiency of the system and at the same time maintaining and in some cases even boosting the overall accuracy. We show that our proposed framework is able to prune up to 90% of the hypotheses while still retaining high recall in top-K results. This level of efficiency enables the discovery algorithm to look for higher-order hypotheses, something that was infeasible until now. Furthermore, the generic formulation allows our approach to be agile to perform both open and closed discovery. We also experimentally validate that the core data-structures upon which the system bases its decision has a high concordance with the opinion of the experts.This coupled with the ability to understand the edge formation process provides us with interpretable results without any manual intervention. The relevant JAVA codes are available at: https://github.com/vishrawas/Medline-Code_v2. Supplementary data are available at Bioinformatics online.
Dambacher, Jeffrey M; Rothlisberg, Peter C; Loneragan, Neil R
2015-01-01
A major decline in the catch of the banana prawn [shrimp], Penaeus (Fenneropenaeus) merguiensis, occurred over a six-year period in the Weipa region of the northeastern Gulf of Carpentaria, Australia. Three main hypotheses have been developed to explain this decline: (1) prawn recruitment collapsed due to overfishing; (2) recruitment collapsed due to a change in the prawn's environment; and (3) adult banana prawns were still present, but fishers could no longer effectively find or catch them. Qualitative mathematical models were used to link population biology, environmental factors, and fishery dynamics to evaluate the alternative hypotheses. This modeling approach provides the means to rapidly integrate knowledge across disciplines and consider alternative hypotheses about how the structure and function of an ecosystem affects its dynamics. Alternative models were constructed to address the different hypotheses and also to encompass a diversity of opinion about the underlying dynamics of the system. Key findings from these analyses are that: instability in the system can arise when discarded fishery bycatch supports relatively high predation pressure; system stability can be enhanced by management of fishing effort or stock catchability; catch per unit effort is not necessarily a reliable indicator of stock abundance; a change in early-season rainfall should affect all stages in the banana prawn's life cycle; and a reduced catch in the Weipa region can create and reinforce a shift in fishing effort away from Weipa. Results from the models informed an approach to test the hypotheses (i.e., an experimental fishing program), and promoted understanding of the system among researchers, management agencies, and industry. The analytical tools developed in this work to address stages of a prawn life cycle and fishery dynamics are generally applicable to any exploited natural. resource.
Kondo, Masaki; Kiyomizu, Kensuke; Goto, Fumiyuki; Kitahara, Tadashi; Imai, Takao; Hashimoto, Makoto; Shimogori, Hiroaki; Ikezono, Tetsuo; Nakayama, Meiho; Watanabe, Norio; Akechi, Tatsuo
2015-01-22
Dizziness or vertigo is associated with both vestibular-balance and psychological factors. A common assessment tool is the Vertigo Symptom Scale (VSS) -short form, which has two subscales: vestibular-balance and autonomic-anxiety. Despite frequent use, the factor structure of the VSS-short form has yet to be confirmed. Here, we clarified the factor structure of the VSS-short form, and assessed the validity and reliability of the Japanese version of this tool. We conducted a cross-sectional, multicenter, psychometric evaluation of patients with non-central dizziness or vertigo persisting for longer than 1 month. Participants completed the VSS-short form, the Dizziness Handicap Inventory, and the Hospital Anxiety and Depression Scale. They also completed the VSS-short form a second time 1-3 days later. The questionnaire was translated into Japanese and cross-culturally adapted. We conducted a confirmatory factor analysis followed by an exploratory factor analysis. Convergent and discriminant validity, internal consistency, and test-retest reliability were evaluated. The total sample and retest sample consisted of 159 and 79 participants, respectively. Model-fitting for a two-subscale structure in a confirmatory factor analysis was poor. An exploratory factor analysis produced a three-factor structure: long-duration vestibular-balance symptoms, short-duration vestibular-balance symptoms, and autonomic-anxiety symptoms. Regarding convergent and discriminant validity, all hypotheses were clearly supported. We obtained high Cronbach's α coefficients for the total score and subscales, ranging from 0.758 to 0.866. Total score and subscale interclass correlation coefficients for test-retest reliability were acceptable, ranging from 0.867 to 0.897. The VSS-short form has a three-factor structure that was cross-culturally well-matched with previous data from the VSS-long version. Thus, it was suggested that vestibular-balance symptoms can be analyzed separately according to symptom duration, which may reflect pathophysiological factors. The VSS-short form can be used to evaluate vestibular-balance symptoms and autonomic-anxiety symptoms, as well as the duration of vestibular-balance symptoms. Further research using the VSS-short form should be required in other languages and populations.
Coumar, Mohane Selvaraj; Chu, Chang-Ying; Lin, Cheng-Wei; Shiao, Hui-Yi; Ho, Yun-Lung; Reddy, Randheer; Lin, Wen-Hsing; Chen, Chun-Hwa; Peng, Yi-Hui; Leou, Jiun-Shyang; Lien, Tzu-Wen; Huang, Chin-Ting; Fang, Ming-Yu; Wu, Szu-Huei; Wu, Jian-Sung; Chittimalla, Santhosh Kumar; Song, Jen-Shin; Hsu, John T-A; Wu, Su-Ying; Liao, Chun-Chen; Chao, Yu-Sheng; Hsieh, Hsing-Pang
2010-07-08
A focused library of furanopyrimidine (350 compounds) was rapidly synthesized in parallel reactors and in situ screened for Aurora and epidermal growth factor receptor (EGFR) kinase activity, leading to the identification of some interesting hits. On the basis of structural biology observations, the hit 1a was modified to better fit the back pocket, producing the potent Aurora inhibitor 3 with submicromolar antiproliferative activity in HCT-116 colon cancer cell line. On the basis of docking studies with EGFR hit 1s, introduction of acrylamide Michael acceptor group led to 8, which inhibited both the wild and mutant EGFR kinase and also showed antiproliferative activity in HCC827 lung cancer cell line. Furthermore, the X-ray cocrystal study of 3 and 8 in complex with Aurora and EGFR, respectively, confirmed their hypothesized binding modes. Library construction, in situ screening, and structure-based drug design (SBDD) strategy described here could be applied for the lead identification of other kinases.
NASA Astrophysics Data System (ADS)
Qin, Yanlin; Qiu, Xueqing; Zhu, J. Y.
2016-10-01
Here we used dilute oxalic acid to pretreat a kraft bleached Eucalyptus pulp (BEP) fibers to facilitate mechanical fibrillation in producing cellulose nanofibrils using disk milling with substantial mechanical energy savings. We successfully applied a reaction kinetics based combined hydrolysis factor (CHFX) as a severity factor to quantitatively control xylan dissolution and BEP fibril deploymerization. More importantly, we were able to accurately predict the degree of polymerization (DP) of disk-milled fibrils using CHFX and milling time or milling energy consumption. Experimentally determined ratio of fibril DP and number mean fibril height (diameter d), DP/d, an aspect ratio measurer, were independent of the processing conditions. Therefore, we hypothesize that cellulose have a longitudinal hierarchical structure as in the lateral direction. Acid hydrolysis and milling did not substantially cut the “natural” chain length of cellulose fibrils. This cellulose longitudinal hierarchical model provides support for using weak acid hydrolysis in the production of cellulose nanofibrils with substantially reduced energy input without negatively affecting fibril mechanical strength.
The future of crystallography in drug discovery
Zheng, Heping; Hou, Jing; Zimmerman, Matthew D; Wlodawer, Alexander; Minor, Wladek
2014-01-01
Introduction X-ray crystallography plays an important role in structure-based drug design (SBDD), and accurate analysis of crystal structures of target macromolecules and macromolecule–ligand complexes is critical at all stages. However, whereas there has been significant progress in improving methods of structural biology, particularly in X-ray crystallography, corresponding progress in the development of computational methods (such as in silico high-throughput screening) is still on the horizon. Crystal structures can be overinterpreted and thus bias hypotheses and follow-up experiments. As in any experimental science, the models of macromolecular structures derived from X-ray diffraction data have their limitations, which need to be critically evaluated and well understood for structure-based drug discovery. Areas covered This review describes how the validity, accuracy and precision of a protein or nucleic acid structure determined by X-ray crystallography can be evaluated from three different perspectives: i) the nature of the diffraction experiment; ii) the interpretation of an electron density map; and iii) the interpretation of the structural model in terms of function and mechanism. The strategies to optimally exploit a macromolecular structure are also discussed in the context of ‘Big Data’ analysis, biochemical experimental design and structure-based drug discovery. Expert opinion Although X-ray crystallography is one of the most detailed ‘microscopes’ available today for examining macromolecular structures, the authors would like to re-emphasize that such structures are only simplified models of the target macromolecules. The authors also wish to reinforce the idea that a structure should not be thought of as a set of precise coordinates but rather as a framework for generating hypotheses to be explored. Numerous biochemical and biophysical experiments, including new diffraction experiments, can and should be performed to verify or falsify these hypotheses. X-ray crystallography will find its future application in drug discovery by the development of specific tools that would allow realistic interpretation of the outcome coordinates and/or support testing of these hypotheses. PMID:24372145
Structured plant metabolomics for the simultaneous exploration of multiple factors.
Vasilev, Nikolay; Boccard, Julien; Lang, Gerhard; Grömping, Ulrike; Fischer, Rainer; Goepfert, Simon; Rudaz, Serge; Schillberg, Stefan
2016-11-17
Multiple factors act simultaneously on plants to establish complex interaction networks involving nutrients, elicitors and metabolites. Metabolomics offers a better understanding of complex biological systems, but evaluating the simultaneous impact of different parameters on metabolic pathways that have many components is a challenging task. We therefore developed a novel approach that combines experimental design, untargeted metabolic profiling based on multiple chromatography systems and ionization modes, and multiblock data analysis, facilitating the systematic analysis of metabolic changes in plants caused by different factors acting at the same time. Using this method, target geraniol compounds produced in transgenic tobacco cell cultures were grouped into clusters based on their response to different factors. We hypothesized that our novel approach may provide more robust data for process optimization in plant cell cultures producing any target secondary metabolite, based on the simultaneous exploration of multiple factors rather than varying one factor each time. The suitability of our approach was verified by confirming several previously reported examples of elicitor-metabolite crosstalk. However, unravelling all factor-metabolite networks remains challenging because it requires the identification of all biochemically significant metabolites in the metabolomics dataset.
de Vocht, Frank; Hannam, Kimberly; Buchan, Iain
2013-05-01
There is a public health need to balance timely generation of hypotheses with cautious causal inference. For rare cancers this is particularly challenging because standard epidemiological study designs may not be able to elucidate causal factors in an early period of newly emerging risks. Alternative methodologies need to be considered for generating and shaping hypotheses prior to definitive investigation. To evaluate whether open-access databases can be used to explore links between potential risk factors and cancers at an ecological level, using the case study of brain and nervous system cancers as an example. National age-adjusted cancer incidence rates were obtained from the GLOBOCAN 2008 resource and combined with data from the United Nations Development Report and the World Bank list of development indicators. Data were analysed using multivariate regression models. Cancer rates, potential confounders and environmental risk factors were available for 165 of 208 countries. 2008 national incidences of brain and nervous system cancers were associated with continent, gross national income in 2008 and Human Development Index Score. The only exogenous risk factor consistently associated with higher incidence was the penetration rate of mobile/cellular telecommunications subscriptions, although other factors were highlighted. According to these ecological results the latency period is at least 11-12 years, but probably more than 20 years. Missing data on cancer incidence and for other potential risk factors prohibit more detailed investigation of exposure-response associations and/or explore other hypotheses. Readily available ecological data may be underused, particularly for the study of risk factors for rare diseases and those with long latencies. The results of ecological analyses in general should not be overinterpreted in causal inference, but equally they should not be ignored where alternative signals of aetiology are lacking.
Excessive Cap-dependent Translation as a Molecular Mechanism Underlying ASD
2012-08-01
SUPPLEMENTARY NOTES 14. ABSTRACT We hypothesize that excessive cap-dependent translation is a causative factor in autism spectrum disorder...compounds to therapeutically target eIF4E-eIF4G interactions and eIF4A for treating patients with ASD. 15. SUBJECT TERMS autism spectrum...Introduction We hypothesize that excessive cap-dependent translation is a causative factor in autism spectrum disorder (ASD). To test this
Neto, Jose Osni Bruggemann; Gesser, Rafael Lehmkuhl; Steglich, Valdir; Bonilauri Ferreira, Ana Paula; Gandhi, Mihir; Vissoci, João Ricardo Nickenig; Pietrobon, Ricardo
2013-01-01
The validation of widely used scales facilitates the comparison across international patient samples. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. The Simple Shoulder Test was translated from English into Brazilian Portuguese, translated back into English, and evaluated for accuracy by an expert committee. It was then administered to 100 patients with shoulder conditions. Psychometric properties were analyzed including factor analysis, internal reliability, test-retest reliability at seven days, and construct validity in relation to the Short Form 36 health survey (SF-36). Factor analysis demonstrated a three factor solution. Cronbach's alpha was 0.82. Test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.84. Associations were observed in the hypothesized direction with all subscales of SF-36 questionnaire. The Simple Shoulder Test translation and cultural adaptation to Brazilian-Portuguese demonstrated adequate factor structure, internal reliability, and validity, ultimately allowing for its use in the comparison with international patient samples.
Neto, Jose Osni Bruggemann; Gesser, Rafael Lehmkuhl; Steglich, Valdir; Bonilauri Ferreira, Ana Paula; Gandhi, Mihir; Vissoci, João Ricardo Nickenig; Pietrobon, Ricardo
2013-01-01
Background The validation of widely used scales facilitates the comparison across international patient samples. The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. Objective The objective of this study was to translate, culturally adapt and validate the Simple Shoulder Test into Brazilian Portuguese. Also we test the stability of factor analysis across different cultures. Methods The Simple Shoulder Test was translated from English into Brazilian Portuguese, translated back into English, and evaluated for accuracy by an expert committee. It was then administered to 100 patients with shoulder conditions. Psychometric properties were analyzed including factor analysis, internal reliability, test-retest reliability at seven days, and construct validity in relation to the Short Form 36 health survey (SF-36). Results Factor analysis demonstrated a three factor solution. Cronbach’s alpha was 0.82. Test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.84. Associations were observed in the hypothesized direction with all subscales of SF-36 questionnaire. Conclusion The Simple Shoulder Test translation and cultural adaptation to Brazilian-Portuguese demonstrated adequate factor structure, internal reliability, and validity, ultimately allowing for its use in the comparison with international patient samples. PMID:23675436
HyQue: evaluating hypotheses using Semantic Web technologies.
Callahan, Alison; Dumontier, Michel; Shah, Nigam H
2011-05-17
Key to the success of e-Science is the ability to computationally evaluate expert-composed hypotheses for validity against experimental data. Researchers face the challenge of collecting, evaluating and integrating large amounts of diverse information to compose and evaluate a hypothesis. Confronted with rapidly accumulating data, researchers currently do not have the software tools to undertake the required information integration tasks. We present HyQue, a Semantic Web tool for querying scientific knowledge bases with the purpose of evaluating user submitted hypotheses. HyQue features a knowledge model to accommodate diverse hypotheses structured as events and represented using Semantic Web languages (RDF/OWL). Hypothesis validity is evaluated against experimental and literature-sourced evidence through a combination of SPARQL queries and evaluation rules. Inference over OWL ontologies (for type specifications, subclass assertions and parthood relations) and retrieval of facts stored as Bio2RDF linked data provide support for a given hypothesis. We evaluate hypotheses of varying levels of detail about the genetic network controlling galactose metabolism in Saccharomyces cerevisiae to demonstrate the feasibility of deploying such semantic computing tools over a growing body of structured knowledge in Bio2RDF. HyQue is a query-based hypothesis evaluation system that can currently evaluate hypotheses about the galactose metabolism in S. cerevisiae. Hypotheses as well as the supporting or refuting data are represented in RDF and directly linked to one another allowing scientists to browse from data to hypothesis and vice versa. HyQue hypotheses and data are available at http://semanticscience.org/projects/hyque.
The use of analysis of variance procedures in biological studies
Williams, B.K.
1987-01-01
The analysis of variance (ANOVA) is widely used in biological studies, yet there remains considerable confusion among researchers about the interpretation of hypotheses being tested. Ambiguities arise when statistical designs are unbalanced, and in particular when not all combinations of design factors are represented in the data. This paper clarifies the relationship among hypothesis testing, statistical modelling and computing procedures in ANOVA for unbalanced data. A simple two-factor fixed effects design is used to illustrate three common parametrizations for ANOVA models, and some associations among these parametrizations are developed. Biologically meaningful hypotheses for main effects and interactions are given in terms of each parametrization, and procedures for testing the hypotheses are described. The standard statistical computing procedures in ANOVA are given along with their corresponding hypotheses. Throughout the development unbalanced designs are assumed and attention is given to problems that arise with missing cells.
Winnie, John A
2012-12-01
Aspen in the Greater Yellowstone Ecosystem are hypothesized to be recovering from decades of heavy browsing by elk due to a behaviorally mediated trophic cascade (BMTC). Several authors have suggested that wolves interact with certain terrain features, creating places of high predation risk at fine spatial scales, and that elk avoid these places, which creates refugia for plants. This hypothesized BMTC could release aspen from elk browsing pressure, leading to a patchy recovery in places of high risk. I tested whether four specific, hypothesized fine-scale risk factors are correlated with changes in current elk browsing pressure on aspen, or with aspen recruitment since wolf reintroduction, in the Daly Creek drainage in Yellowstone National Park, and near two aspen enclosures outside of the park boundary. Aspen were not responding to hypothesized fine-scale risk factors in ways consistent with the current BMTC hypothesis.
Development and initial validation of a cognitive-based work-nonwork conflict scale.
Ezzedeen, Souha R; Swiercz, Paul M
2007-06-01
Current research related to work and life outside work specifies three types of work-nonwork conflict: time, strain, and behavior-based. Overlooked in these models is a cognitive-based type of conflict whereby individuals experience work-nonwork conflict from cognitive preoccupation with work. Four studies on six different groups (N=549) were undertaken to develop and validate an initial measure of this construct. Structural equation modeling confirmed a two-factor, nine-item scale. Hypotheses regarding cognitive-based conflict's relationship with life satisfaction, work involvement, work-nonwork conflict, and work hours were supported. The relationship with knowledge work was partially supported in that only the cognitive dimension of cognitive-based conflict was related to extent of knowledge work. Hypotheses regarding cognitive-based conflict's relationship with family demands were rejected in that the cognitive dimension correlated positively rather than negatively with number of dependent children and perceived family demands. The study provides encouraging preliminary evidence of scale validity.
Rural neighborhoods and child aggression.
Bowen, Natasha K; Wretman, Christopher J
2014-12-01
Structural equation modeling with latent variables was used to evaluate the direct and mediated effects of a neighborhood risk factor (negative teen behaviors) on the parent-report aggressive behavior of 213 students in grades 3 through 5 attending a school in a low-income, rural community. Contagion and social control hypotheses were examined as well as hypotheses about whether the neighborhood served as a microsystem or exosystem for rural pre-adolescents. Analyses took into account the clustering of students and ordinal nature of the data. Findings suggest that rural neighborhoods may operate as both a microsystem and exosystem for children, with direct contagion effects on their aggressive behaviors as well as indirect social control effects through parenting practices. Direct effects on aggression were also found for parenting practices and child reports of friends' negative behaviors. Pre-adolescence may be a transitional stage, when influences of the neighborhood on child behavior begin to compete with influences of caregivers. Findings can inform the timing and targets of violence prevention in rural communities.
Wong, Cho Lee; Ip, Wan Yim; Choi, Kai Chow; Lam, Lai Wah
2015-05-01
To test a hypothesized model that examines the relationship between selected basic conditioning factors, self-care agency, and self-care behaviors among adolescent girls with dysmenorrhea using Orem's self-care deficit nursing theory as a framework. This was a predictive correlational study conducted with a total of 531 secondary school girls. Self-care agency, self-care behaviors, and 11 variables that have been theoretically or empirically justified in previous studies as relevant to basic conditioning factors were selected and collected by means of structured questionnaires. Path analyses were performed to test the hypothesized linkages among variables. Path analysis revealed that age and received menstrual education had both direct and indirect effects through self-care agency on self-care behaviors. Mother's and father's educational level, pain intensity, and self-medication used when experiencing dysmenorrhea only affected the self-care behaviors directly. This is the first study that provided information about the relationship between basic conditioning factors, self-care agency, and self-care behaviors among adolescent girls with dysmenorrhea. Knowledge of the factors influencing self-care behaviors in these adolescent girls will assist healthcare professionals in developing effective interventions to promote self-care and ameliorate the adverse impact of this condition. Interventional strategies that aim at promoting self-care behaviors among adolescent girls with dysmenorrhea should strengthen girls' self-care agency and should target those with a younger age, higher pain intensity, mother with a higher educational level, father with a lower educational level, and those who do not take self-medication for dysmenorrhea. © 2015 Sigma Theta Tau International.
Marshall, Andrew J; Evanovich, Emma K; David, Sarah Jo; Mumma, Gregory H
2018-01-17
High comorbidity rates among emotional disorders have led researchers to examine transdiagnostic factors that may contribute to shared psychopathology. Bifactor models provide a unique method for examining transdiagnostic variables by modelling the common and unique factors within measures. Previous findings suggest that the bifactor model of the Depression Anxiety and Stress Scale (DASS) may provide a method for examining transdiagnostic factors within emotional disorders. This study aimed to replicate the bifactor model of the DASS, a multidimensional measure of psychological distress, within a US adult sample and provide initial estimates of the reliability of the general and domain-specific factors. Furthermore, this study hypothesized that Worry, a theorized transdiagnostic variable, would show stronger relations to general emotional distress than domain-specific subscales. Confirmatory factor analysis was used to evaluate the bifactor model structure of the DASS in 456 US adult participants (279 females and 177 males, mean age 35.9 years) recruited online. The DASS bifactor model fitted well (CFI = 0.98; RMSEA = 0.05). The General Emotional Distress factor accounted for most of the reliable variance in item scores. Domain-specific subscales accounted for modest portions of reliable variance in items after accounting for the general scale. Finally, structural equation modelling indicated that Worry was strongly predicted by the General Emotional Distress factor. The DASS bifactor model is generalizable to a US community sample and General Emotional Distress, but not domain-specific factors, strongly predict the transdiagnostic variable Worry.
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.
Thymocyte emigration is mediated by active movement away from stroma-derived factors
Poznansky, Mark C.; Olszak, Ivona T.; Evans, Richard H.; Wang, Zhengyu; Foxall, Russell B.; Olson, Douglas P.; Weibrecht, Kathryn; Luster, Andrew D.; Scadden, David T.
2002-01-01
T cells leave the thymus at a specific time during differentiation and do not return despite elaboration of known T cell chemoattractants by thymic stroma. We observed differentiation stage–restricted egress of thymocytes from an artificial thymus in which vascular structures or hemodynamics could not have been playing a role. Hypothesizing that active movement of cells away from a thymic product may be responsible, we demonstrated selective reduction in emigration from primary thymus by inhibitors of active movement down a concentration gradient (chemofugetaxis). Immature intrathymic precursors were insensitive to an emigration signal, whereas mature thymocytes and peripheral blood T cells were sensitive. Thymic stroma was noted to elaborate at least two proteins capable of inducing emigration, one of which was stromal cell–derived factor-1. Thymic emigration is mediated, at least in part, by specific fugetaxis-inducing factors to which only mature cells respond. PMID:11956248
The interaction of culture with general job stressors in air traffic controllers.
Shouksmith, G; Taylor, J E
1997-01-01
Elements of the job of Air Traffic Controllers perceived as being stressful were rated for degree of stressfulness by a group of Singaporean controllers. The results were compared with those from earlier studies in Canada and New Zealand. It was hypothesized that the international nature of the job would be reflected in findings from all three groups of controllers. It was further hypothesized, however, that environmental and cultural factors would produce differences among the groups and that these would be greater between the Asian and the two "Western" cultures than between the two earlier samples studied. Results showed that the two Western cultures share 56% common variance in their perceptions of stressfulness, but this changes to 35% between the New Zealand and Singapore groups and only 21% between Canada and Singapore. Although comparison of the factor structure of the stress ratings of the Singapore and New Zealand samples again confirmed a general pattern of underlying stressors related to air traffic control (which fits general occupational models of stress), it also revealed culturally specific components. The nature of these suggests that they are emhedded in the context of Asian environments and cultures. The conclusion is that stress in Air Traffic Controllers is related both to generic occupation stressors and to others that are both organizationally and culturally specific.
NASA Astrophysics Data System (ADS)
Kokornaczyk, Maria Olga; Dinelli, Giovanni; Betti, Lucietta
2013-01-01
The present paper reports on an observation that dendrite-like polycrystalline structures from evaporating droplets of wheat grain leakages exhibit bilateral symmetry. The exactness of this symmetry, measured by means of fluctuating asymmetry, varies depending on the cultivar and stress factor influence, and seems to correspond to the seed germination rate. In the bodies of plants, animals, and humans, the exactness of bilateral symmetry is known to reflect the environmental conditions of an organism's growth, its health, and its success in sexual selection. In polycrystalline structures, formed under the same conditions, the symmetry exactness depends on the properties of the crystallizing solution such as the composition and viscosity; however, it has never been associated with sample quality. We hypothesize here that, as in living nature, the exactness of approximate bilateral symmetry might be considered a quality indicator also in crystallographic methods applied to food quality analysis.
Structure of the Integral Membrane Protein CAAX Protease Ste24p
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pryor Jr., Edward E.; Horanyi, Peter S.; Clark, Kathleen M.
2012-10-26
Posttranslational lipidation provides critical modulation of the functions of some proteins. Isoprenoids (i.e., farnesyl or geranylgeranyl groups) are attached to cysteine residues in proteins containing C-terminal CAAX sequence motifs (where A is an aliphatic residue and X is any residue). Isoprenylation is followed by cleavage of the AAX amino acid residues and, in some cases, by additional proteolytic cuts. We determined the crystal structure of the CAAX protease Ste24p, a zinc metalloprotease catalyzing two proteolytic steps in the maturation of yeast mating pheromone a -factor. The Ste24p core structure is a ring of seven transmembrane helices enclosing a voluminous cavitymore » containing the active site and substrate-binding groove. The cavity is accessible to the external milieu by means of gaps between splayed transmembrane helices. We hypothesize that cleavage proceeds by means of a processive mechanism of substrate insertion, translocation, and ejection.« less
Listening, watching, and reading: the structure and correlates of entertainment preferences.
Rentfrow, Peter J; Goldberg, Lewis R; Zilca, Ran
2011-04-01
People spend considerable amounts of time and money listening to music, watching TV and movies, and reading books and magazines, yet almost no attention in psychology has been devoted to understanding individual differences in preferences for such entertainment. The present research was designed to examine the structure and correlates of entertainment genre preferences. Analyses of the genre preferences of more than 3,000 individuals revealed a remarkably clear factor structure. Using multiple samples, methods, and geographic regions, data converged to reveal five entertainment-preference dimensions: Communal, Aesthetic, Dark, Thrilling, and Cerebral. Preferences for these entertainment dimensions were uniquely related to demographics and personality traits. Results also indicated that personality accounted for significant proportions of variance in entertainment preferences over and above demographics. The results provide a foundation for developing and testing hypotheses about the psychology of entertainment preferences. © 2011 The Authors. Journal of Personality © 2011, Wiley Periodicals, Inc.
Miller, Kathleen E.; Dermen, Kurt H.; Lucke, Joseph F.
2017-01-01
BACKGROUND Young adult use of alcohol mixed with energy drinks (AmEDs) has been linked with elevated risks for a constellation of problem behaviors. These risks may be conditioned by expectancies regarding the effects of caffeine in conjunction with alcohol consumption. The aim of this study was to describe the construction and psychometric evaluation of the Intoxication-Related AmED Expectancies Scale (AmED_EXPI), 15 self-report items measuring beliefs about how the experience of AmED intoxication differs from the experience of noncaffeinated alcohol (NCA) intoxication. METHODS Scale development and testing were conducted using data from a U.S. national sample of 3,105 adolescents and emerging adults aged 13–25. Exploratory and confirmatory factor analyses were conducted to evaluate the factor structure and establish factor invariance across gender, age, and prior experience with AmED use. Cross-sectional and longitudinal analyses examining correlates of AmED use were used to assess construct and predictive validity. RESULTS In confirmatory factor analyses, fit indices for the hypothesized four-factor structure (i.e., Intoxication Management [IM], Alertness [AL], Sociability [SO], and Jitters [JT]) revealed a moderately good fit to the data. Together, these factors accounted for 75.3% of total variance. The factor structure was stable across male/female, teen/young adult, and AmED experience/no experience subgroups. The resultant unit-weighted subscales showed strong internal consistency and satisfactory convergent validity. Baseline scores on the IM, SO, and JT subscales predicted changes in AmED use over a subsequent three-month period. CONCLUSIONS The AmED_EXPI appears to be a reliable and valid tool for measuring expectancies about the effects of caffeine during alcohol intoxication. PMID:28421613
Levant, Ronald F; Hall, Rosalie J; Weigold, Ingrid K; McCurdy, Eric R
2016-10-01
The construct validity of the Male Role Norms Inventory-Short Form (MRNI-SF) was assessed using a latent variable approach implemented with structural equation modeling (SEM). The MRNI-SF was specified as having a bifactor structure, and validation scales were also specified as latent variables. The latent variable approach had the advantages of separating effects of general and specific factors and controlling for some sources of measurement error. Data (N = 484) were from a diverse sample (38.8% men of color, 22.3% men of diverse sexualities) of community-dwelling and college men who responded to an online survey. The construct validity of the MRNI-SF General Traditional Masculinity Ideology factor was supported for all 4 of the proposed latent correlations with: (a) Male Role Attitudes Scale; (b) general factor of Conformity to Masculine Norms Inventory-46; (c) higher-order factor of Gender Role Conflict Scale; and (d) Personal Attributes Questionnaire-Masculinity Scale. Significant correlations with relevant other latent factors provided concurrent validity evidence for the MRNI-SF specific factors of Negativity toward Sexual Minorities, Importance of Sex, Restrictive Emotionality, and Toughness, with all 8 of the hypothesized relationships supported. However, 3 relationships concerning Dominance were not supported. (The construct validity of the remaining 2 MRNI-SF specific factors-Avoidance of Femininity and Self-Reliance through Mechanical Skills was not assessed.) Comparisons were made, and meaningful differences noted, between the latent correlations emphasized in this study and their raw variable counterparts. Results are discussed in terms of the advantages of an SEM approach and the unique characteristics of the bifactor model. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Confirmatory factor analysis of the Autonomy over Tobacco Scale (AUTOS) in adults.
Wellman, Robert J; DiFranza, Joseph R; O'Loughlin, Jennifer
2015-11-01
The Autonomy over Tobacco Scale (AUTOS), a 12-item self-administered questionnaire, was designed to measure autonomy in three correlated lower-order symptom domains: withdrawal, psychological dependence, and cue-induced craving. The factor structure of the AUTOS remains an open question; confirmatory analyses in adolescents supported the hierarchical structure, while exploratory analyses in adolescents and adults yield single-factor solutions. Here we seek to determine whether the hypothesized hierarchical structure is valid in adult smokers. The AUTOS was administered to two independent convenience samples of adult current smokers: a calibration sample recruited in the US for online studies, and a confirmation sample drawn from the prospective Nicotine Dependence in Teens study in Montreal. We tested competing hierarchical and single-factor models using the robust weighted least-squares (WLSMV) estimation method. A single-factor model that allowed correlated error variances between theoretically related items fit well in the calibration sample (n = 434), χ(2)SB(52) = 165.71; χ(2)/df = 3.19; SRMR = 0.03; CFI = 0.96; NNFI = 0.95; RMSEA = 0.07 (95% CI: 0.06, 0.08). Reliability of the single factor was high (ωB = 0.92) and construct validity was adequate. In the confirmation sample (n = 335), a similar model fit well:χ(2)SB(53) = 126.94; χ(2)/df = 2.44; SRMR = 0.04; CFI = 0.95; NNFI = 0.93; RMSEA = 0.07 (95% CI: 0.05, 0.08). Reliability of the single factor was again high (ωB = 0.92) and construct validity was adequate. The AUTOS is unidimensional in adult smokers. Copyright © 2015 Elsevier Ltd. All rights reserved.
Miller, Kathleen E; Dermen, Kurt H; Lucke, Joseph F
2017-06-01
Young adult use of alcohol mixed with energy drinks (AmEDs) has been linked with elevated risks of a constellation of problem behaviors. These risks may be conditioned by expectancies regarding the effects of caffeine in conjunction with alcohol consumption. The aim of this study was to describe the construction and psychometric evaluation of the Intoxication-Related AmED Expectancies Scale (AmED_EXPI), 15 self-report items measuring beliefs about how the experience of AmED intoxication differs from the experience of noncaffeinated alcohol (NCA) intoxication. Scale development and testing were conducted using data from a U.S. national sample of 3,105 adolescents and emerging adults aged 13 to 25. Exploratory and confirmatory factor analyses were conducted to evaluate the factor structure and establish factor invariance across gender, age, and prior experience with AmED use. Cross-sectional and longitudinal analyses examining correlates of AmED use were used to assess construct and predictive validity. In confirmatory factor analyses, fit indices for the hypothesized 4-factor structure (i.e., Intoxication Management [IM], Alertness [AL], Sociability [SO], and Jitters [JT]) revealed a moderately good fit to the data. Together, these factors accounted for 75.3% of total variance. The factor structure was stable across male/female, teen/young adult, and AmED experience/no experience subgroups. The resultant unit-weighted subscales showed strong internal consistency and satisfactory convergent validity. Baseline scores on the IM, SO, and JT subscales predicted changes in AmED use over a subsequent 3-month period. The AmED_EXPI appears to be a reliable and valid tool for measuring expectancies about the effects of caffeine during alcohol intoxication. Copyright © 2017 by the Research Society on Alcoholism.
Compositional grading of InxGa1-xAs/GaAs tunnel junctions enhanced by ErAs nanoparticles
NASA Astrophysics Data System (ADS)
Salas, R.; Krivoy, E. M.; Crook, A. M.; Nair, H. P.; Bank, S. R.
2011-10-01
We investigate the electrical conductivity of GaAs-based tunnel junctions enhanced with semimetallic ErAs nanoparticles. In particular, we examine the effects of digitally-graded InGaAs alloys on the n-type side of the tunnel junction, along with different p-type doping levels. Device characteristics of the graded structures indicate that the n-type Schottky barrier may not be the limiting factor in the tunneling current as initially hypothesized. Moreover, significantly improved forward and reverse bias tunneling currents were observed with increased p-type doping, suggesting p-side limitation.
Social cognitive mediators of parent-child sexual communication.
Evans, W Douglas; Blitstein, Jonathan L; Davis, Kevin C
2011-07-01
To test a social cognitive behavior change model and identify mediators of the effects of the Parents Speak Up National Campaign (PSUNC) on parent-child sexual communication. Investigators used 5 waves of data from an online randomized controlled trial. Latent variables were developed based on item response theory and confirmatory factor analysis. Structural equation modeling was used to test mediation. Outcome expectations mediated effects of social norms and self-efficacy on sexual communication. Other hypothesized mediators were not confirmed. Interventions to promote parent-child sexual communication should target outcome expectations. Future research should investigate parents' health information seeking.
Constructing petal modes from the coherent superposition of Laguerre-Gaussian modes
NASA Astrophysics Data System (ADS)
Naidoo, Darryl; Forbes, Andrew; Ait-Ameur, Kamel; Brunel, Marc
2011-03-01
An experimental approach in generating Petal-like transverse modes, which are similar to what is seen in porro-prism resonators, has been successfully demonstrated. We hypothesize that the petal-like structures are generated from a coherent superposition of Laguerre-Gaussian modes of zero radial order and opposite azimuthal order. To verify this hypothesis, visually based comparisons such as petal peak to peak diameter and the angle between adjacent petals are drawn between experimental data and simulated data. The beam quality factor of the Petal-like transverse modes and an inner product interaction is also experimentally compared to numerical results.
Re-inventing collectivism? Using innovation collectives to create and grow new technology firms
NASA Astrophysics Data System (ADS)
Hudson, David; Tanev, Stoyan
2012-03-01
Academic spin-offs are an important mechanism to develop the regional economy and support their parent institutions. This research applies the lessons learned from an action research project focusing on the development of a model and 10 hypotheses that examine university spin-off efficiency. The formation of the academic spin-off is conceptualized to be embedded in a collective that includes entrepreneurs and those who help them transform their ideas into ventures. Ten factors organized into two constructs - idea-venture path and collective structure, are identified as determinants of academic spin-off efficiency.
Re-inventing collectivism? Using innovation collectives to create and grow new technology firms
NASA Astrophysics Data System (ADS)
Hudson, David; Tanev, Stoyan
2011-10-01
Academic spin-offs are an important mechanism to develop the regional economy and support their parent institutions. This research applies the lessons learned from an action research project focusing on the development of a model and 10 hypotheses that examine university spin-off efficiency. The formation of the academic spin-off is conceptualized to be embedded in a collective that includes entrepreneurs and those who help them transform their ideas into ventures. Ten factors organized into two constructs - idea-venture path and collective structure, are identified as determinants of academic spin-off efficiency.
Etiology of depression comorbidity in combat-related PTSD: a review of the literature.
Stander, Valerie A; Thomsen, Cynthia J; Highfill-McRoy, Robyn M
2014-03-01
Posttraumatic stress disorder is often diagnosed with other mental health problems, particularly depression. Although PTSD comorbidity has been associated with more severe and chronic symptomology, relationships among commonly co-occurring disorders are not well understood. The purpose of this study was to review the literature regarding the development of depression comorbid with combat-related PTSD among military personnel. We summarize results of commonly tested hypotheses about the etiology of PTSD and depression comorbidity, including (1) causal hypotheses, (2) common factor hypotheses, and (3) potential confounds. Evidence suggests that PTSD may be a causal risk factor for subsequent depression; however, associations are likely complex, involving bidirectional causality, common risk factors, and common vulnerabilities. The unique nature of PTSD-depression comorbidity in the context of military deployment and combat exposure is emphasized. Implications of our results for clinical practice and future research are discussed. Published by Elsevier Ltd.
Factors Affecting the Vocational Calling of Laboratory Animal Care and Research Employees
Boivin, Gregory P; Markert, Ronald J
2016-01-01
We surveyed laboratory animal care and research workers to determine the factors affecting their vocational calling. The survey comprised 56 questions in 4 groups: passion, job stability or happiness, work volition, and demographics. We hypothesized that personnel who worked in the field a longer time, were older, had higher education levels, were involved with AALAS, and in higher positions in their organization were more likely to indicate a calling to the laboratory animal care field. In addition, we hypothesized that job satisfaction and classifying one's job as a calling were positively related to organizational support and work volition. Overall, 44% of respondents categorized their work as at least partially a calling. Those working at a higher level in the position of laboratory animal technician and in the organization were more likely to view their work as a calling. Increasing education level was related to work being a calling. Overall, vocational calling was significantly associated with higher pay, but technicians were the only subgroup where calling and higher pay were significantly related. Vocational calling and job satisfaction were associated with organizational support. For our sample of workers in the animal care field, other factors analyzed were not related to work being considered a calling. Leaders in the field of animal care may find our survey results valuable as they strive to adapt their organization's structure to the perceptions of their workforce with regard to their sense of calling. PMID:27931315
Antibiotics for coughing in general practice: a qualitative decision analysis.
Coenen, S; Van Royen, P; Vermeire, E; Hermann, I; Denekens, J
2000-10-01
In family practice, medical decisions are prompted most often by complaints about coughing. There is no single yardstick for the differential diagnosis of respiratory tract infections (RTIs). In 80% of cases, the excessive use of antibiotics in the treatment of RTIs is caused by the prescription behaviour of GPs. Our aim was to explicate GPs' diagnostic (and therapeutic) decisions regarding adult patients who consult them with complaints about coughing, and to investigate what determines decision making. Exploratory, descriptive focus groups were held with GPs. Hypotheses were generated on the basis of 'qualitative content analysis'. Results. Twenty-four GPs participated in four semi-structured group discussions. In order to differentiate RTIs from other possible diagnoses, less likely diagnoses were not ruled out explicitly. In the case of suspected RTI, there was a low degree of certainty in the differentiation between RTIs (e.g. between bronchitis and pneumonia). Clinical signs and symptoms, which determine the probability of disease, often left GPs with reasonable diagnostic doubt. In the end, the decision whether or not to prescribe antibiotics was taken. GPs' prescription behaviour was also determined by doctor- and patient-related factors (e.g. having missed pneumonia once, patient expectations). The 'chagrin factor' explains why these factors lead to a shift in the action threshold, in favour of antibiotics. This inductive research method enabled the generation of meaningful hypotheses regarding the complex decision processes pursued by GPs. The authors are developing an educational intervention that builds on these findings, focusing on the prescribing decision.
Kim, Sunny S.; Nguyen, Tuan T.; Hajeebhoy, Nemat; Tran, Lan M.; Alayon, Silvia; Ruel, Marie T.; Rawat, Rahul; Frongillo, Edward A.; Menon, Purnima
2016-01-01
Abstract The pathways through which behavior change interventions impact breastfeeding practices have not been well studied. This study aimed to examine: (1) the effects of exposure to mass media and interpersonal counseling on exclusive breastfeeding (EBF) and hypothesized psychosocial determinants (i.e. knowledge, intention, beliefs, social norms, and self‐efficacy); and (2) the pathways through which exposure to mass media and interpersonal counseling are associated with EBF. We used survey data from mothers with children < 2 year (n = 2045) from the 2013 process evaluation of Alive & Thrive's program in Viet Nam. Multiple linear regression analyses and structural equation modeling were used to estimate effects. Exposure to mass media only, interpersonal counseling only, both or neither was 51%, 5%, 19% and 25%, respectively. Exposure to both mass media and interpersonal counseling had additive effects on EBF as well as on related psychosocial factors, compared with no exposure. For example, EBF prevalence was 26.1 percentage points (pp) higher in the group that received interpersonal counseling only, 3.9 pp higher in the mass media group and 31.8 pp higher in the group that received both interventions. As hypothesized, more than 90% of the total effect of the two interventions on EBF was explained by the psychosocial factors measured. Our findings suggest that combining different behavior change interventions leads to greater changes in psychosocial factors, which in turn positively affects breastfeeding behaviors. PMID:27334544
Solomon, Scott E.; Bacci, Mauricio; Martins, Joaquim; Vinha, Giovanna Gonçalves; Mueller, Ulrich G.
2008-01-01
The evolutionary basis for high species diversity in tropical regions of the world remains unresolved. Much research has focused on the biogeography of speciation in the Amazon Basin, which harbors the greatest diversity of terrestrial life. The leading hypotheses on allopatric diversification of Amazonian taxa are the Pleistocene refugia, marine incursion, and riverine barrier hypotheses. Recent advances in the fields of phylogeography and species-distribution modeling permit a modern re-evaluation of these hypotheses. Our approach combines comparative, molecular phylogeographic analyses using mitochondrial DNA sequence data with paleodistribution modeling of species ranges at the last glacial maximum (LGM) to test these hypotheses for three co-distributed species of leafcutter ants (Atta spp.). The cumulative results of all tests reject every prediction of the riverine barrier hypothesis, but are unable to reject several predictions of the Pleistocene refugia and marine incursion hypotheses. Coalescent dating analyses suggest that population structure formed recently (Pleistocene-Pliocene), but are unable to reject the possibility that Miocene events may be responsible for structuring populations in two of the three species examined. The available data therefore suggest that either marine incursions in the Miocene or climate changes during the Pleistocene—or both—have shaped the population structure of the three species examined. Our results also reconceptualize the traditional Pleistocene refugia hypothesis, and offer a novel framework for future research into the area. PMID:18648512
The revelation effect: A meta-analytic test of hypotheses.
Aßfalg, André; Bernstein, Daniel M; Hockley, William
2017-12-01
Judgments can depend on the activity directly preceding them. An example is the revelation effect whereby participants are more likely to claim that a stimulus is familiar after a preceding task, such as solving an anagram, than without a preceding task. We test conflicting predictions of four revelation-effect hypotheses in a meta-analysis of 26 years of revelation-effect research. The hypotheses' predictions refer to three subject areas: (1) the basis of judgments that are subject to the revelation effect (recollection vs. familiarity vs. fluency), (2) the degree of similarity between the task and test item, and (3) the difficulty of the preceding task. We use a hierarchical multivariate meta-analysis to account for dependent effect sizes and variance in experimental procedures. We test the revelation-effect hypotheses with a model selection procedure, where each model corresponds to a prediction of a revelation-effect hypothesis. We further quantify the amount of evidence for one model compared to another with Bayes factors. The results of this analysis suggest that none of the extant revelation-effect hypotheses can fully account for the data. The general vagueness of revelation-effect hypotheses and the scarcity of data were the major limiting factors in our analyses, emphasizing the need for formalized theories and further research into the puzzling revelation effect.
Kumar, Supriya; Piper, Kaitlin; Galloway, David D; Hadler, James L; Grefenstette, John J
2015-09-23
In New Haven County, CT (NHC), influenza hospitalization rates have been shown to increase with census tract poverty in multiple influenza seasons. Though multiple factors have been hypothesized to cause these inequalities, including population structure, differential vaccine uptake, and differential access to healthcare, the impact of each in generating observed inequalities remains unknown. We can design interventions targeting factors with the greatest explanatory power if we quantify the proportion of observed inequalities that hypothesized factors are able to generate. Here, we ask if population structure is sufficient to generate the observed area-level inequalities in NHC. To our knowledge, this is the first use of simulation models to examine the causes of differential poverty-related influenza rates. Using agent-based models with a census-informed, realistic representation of household size, age-structure, population density in NHC census tracts, and contact rates in workplaces, schools, households, and neighborhoods, we measured poverty-related differential influenza attack rates over the course of an epidemic with a 23 % overall clinical attack rate. We examined the role of asthma prevalence rates as well as individual contact rates and infection susceptibility in generating observed area-level influenza inequalities. Simulated attack rates (AR) among adults increased with census tract poverty level (F = 30.5; P < 0.001) in an epidemic caused by a virus similar to A (H1N1) pdm09. We detected a steeper, earlier influenza rate increase in high-poverty census tracts-a finding that we corroborate with a temporal analysis of NHC surveillance data during the 2009 H1N1 pandemic. The ratio of the simulated adult AR in the highest- to lowest-poverty tracts was 33 % of the ratio observed in surveillance data. Increasing individual contact rates in the neighborhood did not increase simulated area-level inequalities. When we modified individual susceptibility such that it was inversely proportional to household income, inequalities in AR between high- and low-poverty census tracts were comparable to those observed in reality. To our knowledge, this is the first study to use simulations to probe the causes of observed inequalities in influenza disease patterns. Knowledge of the causes and their relative explanatory power will allow us to design interventions that have the greatest impact on reducing inequalities. Differential exposure due to population structure in our realistic simulation model explains a third of the observed inequality. Differential susceptibility to disease due to prevailing chronic conditions, vaccine uptake, and smoking should be considered in future models in order to quantify the role of additional factors in generating influenza inequalities.
The Rosenberg Self-Esteem Scale: a bifactor answer to a two-factor question?
McKay, Michael T; Boduszek, Daniel; Harvey, Séamus A
2014-01-01
Despite its long-standing and widespread use, disagreement remains regarding the structure of the Rosenberg Self-Esteem Scale (RSES). In particular, concern remains regarding the degree to which the scale assesses self-esteem as a unidimensional or multidimensional (positive and negative self-esteem) construct. Using a sample of 3,862 high school students in the United Kingdom, 4 models were tested: (a) a unidimensional model, (b) a correlated 2-factor model in which the 2 latent variables are represented by positive and negative self-esteem, (c) a hierarchical model, and (d) a bifactor model. The totality of results including item loadings, goodness-of-fit indexes, reliability estimates, and correlations with self-efficacy measures all supported the bifactor model, suggesting that the 2 hypothesized factors are better understood as "grouping" factors rather than as representative of latent constructs. Accordingly, this study supports the unidimensionality of the RSES and the scoring of all 10 items to produce a global self-esteem score.
Moshier, Samantha J; Landau, Aaron J; Hearon, Bridget A; Stein, Aliza T; Greathouse, Lee; Smits, Jasper A J; Otto, Michael W
2016-01-01
Compensatory eating in response to exercise may be an obstacle to achieving weight-loss and fitness goals. In this study we develop and conduct a preliminary examination of the psychometric properties of the Compensatory Eating Motives Questionnaire (CEMQ), a self-report questionnaire of motives for compensatory eating. Development and testing of the CEMQ was conducted in two student samples. Of respondents, 75% reported engaging in compensatory eating. Factor analysis yielded factors representing three domains of motives for compensatory eating: Eating for Reward, Eating for Recovery, and Eating for Relief. Internal consistency of the factors was adequate, and the factor structure was replicated. Correlations between the CEMQ subscales and trait questionnaires supported hypotheses for convergent and divergent validity. These results encourage further investigation of compensatory eating as a potential obstacle to weight loss, and support the continued assessment of the CEMQ as a tool to measure three conceptually distinct motives for compensatory eating.
Validation of the Work-Life Balance Culture Scale (WLBCS).
Nitzsche, Anika; Jung, Julia; Kowalski, Christoph; Pfaff, Holger
2014-01-01
The purpose of this paper is to describe the theoretical development and initial validation of the newly developed Work-Life Balance Culture Scale (WLBCS), an instrument for measuring an organizational culture that promotes the work-life balance of employees. In Study 1 (N=498), the scale was developed and its factorial validity tested through exploratory factor analyses. In Study 2 (N=513), confirmatory factor analysis (CFA) was performed to examine model fit and retest the dimensional structure of the instrument. To assess construct validity, a priori hypotheses were formulated and subsequently tested using correlation analyses. Exploratory and confirmatory factor analyses revealed a one-factor model. Results of the bivariate correlation analyses may be interpreted as preliminary evidence of the scale's construct validity. The five-item WLBCS is a new and efficient instrument with good overall quality. Its conciseness makes it particularly suitable for use in employee surveys to gain initial insight into a company's perceived work-life balance culture.
Assessment of children's emotional adjustment: construction and validation of a new instrument.
Thorlacius, Ö; Gudmundsson, E
2015-09-01
The present study describes the Children's Emotional Adjustment Scale (CEAS), a 47-item parent-reported scale designed to capture children's emotional functioning on four continuous dimensions. A large community sample of mothers of children (n = 606) aged 6-13 years was used to examine the psychometric properties of the CEAS. Exploratory and confirmatory factor analysis supported the hypothesized four-factor structure of the instrument: (1) temper control; (2) anxiety control; (3) mood repair; and (4) social assertiveness. Cronbach's alphas for the factors were consistently above 0.90, and convergent validity of the factors was satisfactory with maternal ratings of child psychopathology. Children rated by their mothers as having emotional problems in the clinical range on the Strengths and Difficulties Questionnaire had significantly lower scores on the CEAS scales. The CEAS is a psychometrically sound instrument, covering healthy emotional adjustment as well as maladjustment. The scale might prove to be valuable in the assessment and screening of behaviours underlying child psychopathology. © 2014 John Wiley & Sons Ltd.
Psychometric Evaluation of the Altered States of Consciousness Rating Scale (OAV)
Studerus, Erich; Gamma, Alex; Vollenweider, Franz X.
2010-01-01
Background The OAV questionnaire has been developed to integrate research on altered states of consciousness (ASC). It measures three primary and one secondary dimensions of ASC that are hypothesized to be invariant across ASC induction methods. The OAV rating scale has been in use for more than 20 years and applied internationally in a broad range of research fields, yet its factorial structure has never been tested by structural equation modeling techniques and its psychometric properties have never been examined in large samples of experimentally induced ASC. Methodology/Principal Findings The present study conducted a psychometric evaluation of the OAV in a sample of psilocybin (n = 327), ketamine (n = 162), and MDMA (n = 102) induced ASC that was obtained by pooling data from 43 experimental studies. The factorial structure was examined by confirmatory factor analysis, exploratory structural equation modeling, hierarchical item clustering (ICLUST), and multiple indicators multiple causes (MIMIC) modeling. The originally proposed model did not fit the data well even if zero-constraints on non-target factor loadings and residual correlations were relaxed. Furthermore, ICLUST suggested that the “oceanic boundlessness” and “visionary restructuralization” factors could be combined on a high level of the construct hierarchy. However, because these factors were multidimensional, we extracted and examined 11 new lower order factors. MIMIC modeling indicated that these factors were highly measurement invariant across drugs, settings, questionnaire versions, and sexes. The new factors were also demonstrated to have improved homogeneities, satisfactory reliabilities, discriminant and convergent validities, and to differentiate well among the three drug groups. Conclusions/Significance The original scales of the OAV were shown to be multidimensional constructs. Eleven new lower order scales were constructed and demonstrated to have desirable psychometric properties. The new lower order scales are most likely better suited to assess drug induced ASC. PMID:20824211
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cho,Y.; Jones, B.; Vermeire, J.
2007-01-01
Hookworms, parasitic nematodes that infect nearly one billion people worldwide, are a major cause of anemia and malnutrition. We hypothesize that hookworms actively manipulate the host immune response through the production of specific molecules designed to facilitate infection by larval stages and adult worm survival within the intestine. A full-length cDNA encoding a secreted orthologue of the human cytokine, Macrophage Migration Inhibitory Factor (MIF) has been cloned from the hookworm Ancylostoma ceylanicum. Elucidation of the three-dimensional crystal structure of recombinant AceMIF (rAceMIF) revealed an overall structural homology with significant differences in the tautomerase sites of the human and hookworm proteins.more » The relative bioactivities of human and hookworm MIF proteins were compared using in vitro assays of tautomerase activity, macrophage migration, and binding to MIF receptor CD74. The activity of rAceMIF was not inhibited by the ligand ISO-1, which was previously determined to be an inhibitor of the catalytic site of human MIF. These data define unique immunological, structural, and functional characteristics of AceMIF, thereby establishing the potential for selectively inhibiting the hookworm cytokine as a means of reducing parasite survival and disease pathogenesis.« less
Zhuang, Zhihao; Yoder, Bonita L; Burgers, Peter M J; Benkovic, Stephen J
2006-02-21
Numerous proteins that function in DNA metabolic pathways are known to interact with the proliferating cell nuclear antigen (PCNA). The important function of PCNA in stimulating various cellular activities requires its topological linkage with DNA. Loading of the circular PCNA onto duplex DNA requires the activity of a clamp-loader [replication factor C (RFC)] complex and the energy derived from ATP hydrolysis. The mechanistic and structural details regarding PCNA loading by the RFC complex are still developing. In particular, the positive identification of a long-hypothesized structure of an open clamp-RFC complex as an intermediate in loading has remained elusive. In this study, we capture an open yeast PCNA clamp in a complex with RFC through fluorescence energy transfer experiments. We also follow the topological transitions of PCNA in the various steps of the clamp-loading pathway through both steady-state and stopped-flow fluorescence studies. We find that ATP effectively drives the clamp-loading process to completion with the formation of the closed PCNA bound to DNA, whereas ATPgammaS cannot. The information derived from this work complements that obtained from previous structural and mechanistic studies and provides a more complete picture of a eukaryotic clamp-loading pathway using yeast as a paradigm.
Lee, Edmund W J; Shin, Mincheol; Kawaja, Ariffin; Ho, Shirley S
2016-05-01
As knowledge acquisition is an important component of health communication research, this study examines factors associated with Singaporean women's breast cancer knowledge using an augmented cognitive mediation model. We conducted a nationally representative study that surveyed 802 women between the ages of 30 and 70 using random-digit dialing. The results supported the augmented cognitive mediation model, which proposes the inclusion of risk perception as a motivator of health information seeking and structural knowledge as an additional knowledge dimension. There was adequate support for the hypothesized paths in the model. Risk perception was positively associated with attention to newspaper, television, Internet, and interpersonal communication. Attention to the three media channels was associated with interpersonal communication, but only newspaper and television attention were associated with elaboration. Interpersonal communication was positively associated with structural knowledge, whereas elaboration was associated with both factual and structural knowledge. Differential indirect effects between media attention and knowledge dimensions via interpersonal communication and elaboration were found. Theoretical and practical implications are discussed.
Crystal structures of a group II intron maturase reveal a missing link in spliceosome evolution.
Zhao, Chen; Pyle, Anna Marie
2016-06-01
Group II introns are self-splicing ribozymes that are essential in many organisms, and they have been hypothesized to share a common evolutionary ancestor with the spliceosome. Although structural similarity of RNA components supports this connection, it is of interest to determine whether associated protein factors also share an evolutionary heritage. Here we present the crystal structures of reverse transcriptase (RT) domains from two group II intron-encoded proteins (maturases) from Roseburia intestinalis and Eubacterium rectale, obtained at 1.2-Å and 2.1-Å resolution, respectively. These domains are more similar in architecture to the spliceosomal Prp8 RT-like domain than to any other RTs, and they share substantial similarity with flaviviral RNA polymerases. The RT domain itself is sufficient for binding intron RNA with high affinity and specificity, and it is contained within an active RT enzyme. These studies provide a foundation for understanding structure-function relationships within group II intron-maturase complexes.
A multi-agent safety response model in the construction industry.
Meliá, José L
2015-01-01
The construction industry is one of the sectors with the highest accident rates and the most serious accidents. A multi-agent safety response approach allows a useful diagnostic tool in order to understand factors affecting risk and accidents. The special features of the construction sector can influence the relationships among safety responses along the model of safety influences. The purpose of this paper is to test a model explaining risk and work-related accidents in the construction industry as a result of the safety responses of the organization, the supervisors, the co-workers and the worker. 374 construction employees belonging to 64 small Spanish construction companies working for two main companies participated in the study. Safety responses were measured using a 45-item Likert-type questionnaire. The structure of the measure was analyzed using factor analysis and the model of effects was tested using a structural equation model. Factor analysis clearly identifies the multi-agent safety dimensions hypothesized. The proposed safety response model of work-related accidents, involving construction specific results, showed a good fit. The multi-agent safety response approach to safety climate is a useful framework for the assessment of organizational and behavioral risks in construction.
Van Geest, Rob J.; Leeuwis, Jan Willem; Dendooven, Amélie; Pfister, Frederick; Bosch, Klazien; Hoeben, Kees A.; Vogels, Ilse M.C.; Van der Giezen, Dionne M.; Dietrich, Nadine; Hammes, Hans-Peter; Goldschmeding, Roel; Klaassen, Ingeborg; Van Noorden, Cornelis J.F.
2014-01-01
Early retinal vascular changes in the development of diabetic retinopathy (DR) include capillary basal lamina (BL) thickening, pericyte loss and the development of acellular capillaries. Expression of the CCN (connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed) family member CCN2 or connective tissue growth factor (CTGF), a potent inducer of the expression of BL components, is upregulated early in diabetes. Diabetic mice lacking one functional CTGF allele (CTGF+/−) do not show this BL thickening. As early events in DR may be interrelated, we hypothesized that CTGF plays a role in the pathological changes of retinal capillaries other than BL thickening. We studied the effects of long-term (6-8 months) streptozotocin-induced diabetes on retinal capillary BL thickness, numbers of pericytes and the development of acellular capillaries in wild type and CTGF+/− mice. Our results show that an absence of BL thickening of retinal capillaries in long-term diabetic CTGF+/− mice is associated with reduced pericyte dropout and reduced formation of acellular capillaries. We conclude that CTGF is involved in structural retinal vascular changes in diabetic rodents. Inhibition of CTGF in the eye may therefore be protective against the development of DR. PMID:24217924
Brain-derived neurotrophic factor mediates cognitive improvements following acute exercise.
Borror, Andrew
2017-09-01
The mechanisms causing improved cognition following acute exercise are poorly understood. This article proposes that brain-derived neurotrophic factor (BDNF) is the main factor contributing to improved cognition following exercise. Additionally, it argues that cerebral blood flow (CBF) and oxidative stress explain the release of BDNF from cerebral endothelial cells. One way to test these hypotheses is to block endothelial function and measure the effect on BDNF levels and cognitive performance. The CBF and oxidative stress can also be examined in relationship to BDNF using a multiple linear regression. If these hypotheses are true, there would be a linear relationship between CBF+oxidative stress and BDNF levels as well as between BDNF levels and cognitive performance. The novelty of these hypotheses comes from the emphasis on the cerebral endothelium and the interplay between BDNF, CBF, and oxidative stress. If found to be valid, these hypotheses would draw attention to the cerebral endothelium and provide direction for future research regarding methods to optimize BDNF release and enhance cognition. Elucidating these mechanisms would provide direction for expediting recovery in clinical populations, such as stroke, and maintaining quality of life in the elderly. Copyright © 2017 Elsevier Ltd. All rights reserved.
On the stability of lung parenchymal lesions with applications to early pneumothorax diagnosis.
Bhandarkar, Archis R; Banerjee, Rohan; Seshaiyer, Padmanabhan
2013-01-01
Spontaneous pneumothorax, a prevalent medical challenge in most trauma cases, is a form of sudden lung collapse closely associated with risk factors such as lung cancer and emphysema. Our work seeks to explore and quantify the currently unknown pathological factors underlying lesion rupture in pneumothorax through biomechanical modeling. We hypothesized that lesion instability is closely associated with elastodynamic strain of the pleural membrane from pulsatile air flow and collagen-elastin dynamics. Based on the principles of continuum mechanics and fluid-structure interaction, our proposed model coupled isotropic tissue deformation with pressure from pulsatile air motion and the pleural fluid. Next, we derived mathematical instability criteria for our ordinary differential equation system and then translated these mathematical instabilities to physically relevant structural instabilities via the incorporation of a finite energy limiter. The introduction of novel biomechanical descriptions for collagen-elastin dynamics allowed us to demonstrate that changes in the protein structure can lead to a transition from stable to unstable domains in the material parameter space for a general lesion. This result allowed us to create a novel streamlined algorithm for detecting material instabilities in transient lung CT scan data via analyzing deformations in a local tissue boundary.
Social structure of collared peccaries (Pecari tajacu): does relatedness matter?
Biondo, Cibele; Izar, Patrícia; Miyaki, Cristina Y; Bussab, Vera S R
2014-11-01
Relatedness is considered an important factor in shaping social structure as the association among kin might facilitate cooperation via inclusive fitness benefits. We addressed here the influence of relatedness on the social structure of a Neotropical ungulate, the collared peccary (Pecari tajacu). As peccaries are highly social and cooperative, live in stable cohesive herds and show certain degree of female philopatry and high mean relatedness within herds, we hypothesized that kin would be spatially closer and display more amicable and less agonistic interactions than non-kin. We recorded spatial association patterns and rates of interactions of two captive groups. Pairwise relatedness was calculated based on microsatellite data. As predicted, we found that kin were spatially closer than non-kin, which suggests that relatedness is a good predictor of spatial association in peccaries. However, relatedness did not predict the rates of social interactions. Although our results indirectly indicate some role of sex, age and familiarity, further studies are needed to clarify the factors that shape the rates of interactions in collared peccaries. This article is part of a Special Issue entitled: Neotropical Behaviour. Copyright © 2014 Elsevier B.V. All rights reserved.
Spence Laschinger, Heather K; Nosko, Amanda; Wilk, Piotr; Finegan, Joan
2014-12-01
Recruitment and retention strategies have emphasized the importance of positive work environments that support professional nursing practice for sustaining the nursing workforce. Unit leadership that creates empowering workplace conditions plays a key role in establishing supportive practice environments that increase work effectiveness, and, ultimately, improves job satisfaction. To test a multi-level model examining the effect of both contextual and individual factors on individual nurse job satisfaction. At the unit level, structural empowerment and support for professional nursing practice (organizational resources) were hypothesized to be predictors of unit level effectiveness. At the individual level, core self-evaluation, and psychological empowerment (intrapersonal resources) were modeled as predictors of nurse job satisfaction one year later. Cross-level unit effects on individual nurses' job satisfaction were also examined. This study employed a longitudinal survey design with 545 staff nurses from 49 hospital units in Ontario, Canada. Participants completed a survey at two points in time (response rate of 40%) with standardized measures of the major study variables in the hypothesized model. Multilevel structural equation modeling was used to test the model. Nurses shared perceptions of structural empowerment on their units indirectly influenced their shared perceptions of unit effectiveness (Level 2) through perceived unit support for professional nursing practice, which in turn, had a significant positive direct effect on unit effectiveness (Level 2). Unit effectiveness was also strongly related to individual nurse job satisfaction one year later. At Level 1, higher core self-evaluation had a direct and indirect effect on job satisfaction through increased psychological empowerment. The results suggest that nurses' job satisfaction is influenced by a combination of individual and contextual factors demonstrating utility in considering both sources of nurses' satisfaction with their work in creating effective nursing work environments. Copyright © 2014 Elsevier Ltd. All rights reserved.
Hishiki, Asami; Hara, Kodai; Ikegaya, Yuzu; Yokoyama, Hideshi; Shimizu, Toshiyuki; Sato, Mamoru; Hashimoto, Hiroshi
2015-05-22
HLTF (helicase-like transcription factor) is a yeast RAD5 homolog found in mammals. HLTF has E3 ubiquitin ligase and DNA helicase activities, and plays a pivotal role in the template-switching pathway of DNA damage tolerance. HLTF has an N-terminal domain that has been designated the HIRAN (HIP116 and RAD5 N-terminal) domain. The HIRAN domain has been hypothesized to play a role in DNA binding; however, the structural basis of, and functional evidence for, the HIRAN domain in DNA binding has remained unclear. Here we show for the first time the crystal structure of the HIRAN domain of human HLTF in complex with DNA. The HIRAN domain is composed of six β-strands and two α-helices, forming an OB-fold structure frequently found in ssDNA-binding proteins, including in replication factor A (RPA). Interestingly, this study reveals that the HIRAN domain interacts with not only with a single-stranded DNA but also with a duplex DNA. Furthermore, the structure unexpectedly clarifies that the HIRAN domain specifically recognizes the 3'-end of DNA. These results suggest that the HIRAN domain functions as a sensor to the 3'-end of the primer strand at the stalled replication fork and that the domain facilitates fork regression. HLTF is recruited to a damaged site through the HIRAN domain at the stalled replication fork. Furthermore, our results have implications for the mechanism of template switching. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
HyQue: evaluating hypotheses using Semantic Web technologies
2011-01-01
Background Key to the success of e-Science is the ability to computationally evaluate expert-composed hypotheses for validity against experimental data. Researchers face the challenge of collecting, evaluating and integrating large amounts of diverse information to compose and evaluate a hypothesis. Confronted with rapidly accumulating data, researchers currently do not have the software tools to undertake the required information integration tasks. Results We present HyQue, a Semantic Web tool for querying scientific knowledge bases with the purpose of evaluating user submitted hypotheses. HyQue features a knowledge model to accommodate diverse hypotheses structured as events and represented using Semantic Web languages (RDF/OWL). Hypothesis validity is evaluated against experimental and literature-sourced evidence through a combination of SPARQL queries and evaluation rules. Inference over OWL ontologies (for type specifications, subclass assertions and parthood relations) and retrieval of facts stored as Bio2RDF linked data provide support for a given hypothesis. We evaluate hypotheses of varying levels of detail about the genetic network controlling galactose metabolism in Saccharomyces cerevisiae to demonstrate the feasibility of deploying such semantic computing tools over a growing body of structured knowledge in Bio2RDF. Conclusions HyQue is a query-based hypothesis evaluation system that can currently evaluate hypotheses about the galactose metabolism in S. cerevisiae. Hypotheses as well as the supporting or refuting data are represented in RDF and directly linked to one another allowing scientists to browse from data to hypothesis and vice versa. HyQue hypotheses and data are available at http://semanticscience.org/projects/hyque. PMID:21624158
DIA-datasnooping and identifiability
NASA Astrophysics Data System (ADS)
Zaminpardaz, S.; Teunissen, P. J. G.
2018-04-01
In this contribution, we present and analyze datasnooping in the context of the DIA method. As the DIA method for the detection, identification and adaptation of mismodelling errors is concerned with estimation and testing, it is the combination of both that needs to be considered. This combination is rigorously captured by the DIA estimator. We discuss and analyze the DIA-datasnooping decision probabilities and the construction of the corresponding partitioning of misclosure space. We also investigate the circumstances under which two or more hypotheses are nonseparable in the identification step. By means of a theorem on the equivalence between the nonseparability of hypotheses and the inestimability of parameters, we demonstrate that one can forget about adapting the parameter vector for hypotheses that are nonseparable. However, as this concerns the complete vector and not necessarily functions of it, we also show that parameter functions may exist for which adaptation is still possible. It is shown how this adaptation looks like and how it changes the structure of the DIA estimator. To demonstrate the performance of the various elements of DIA-datasnooping, we apply the theory to some selected examples. We analyze how geometry changes in the measurement setup affect the testing procedure, by studying their partitioning of misclosure space, the decision probabilities and the minimal detectable and identifiable biases. The difference between these two minimal biases is highlighted by showing the difference between their corresponding contributing factors. We also show that if two alternative hypotheses, say Hi and Hj , are nonseparable, the testing procedure may have different levels of sensitivity to Hi -biases compared to the same Hj -biases.
Brief Self-Efficacy Scales for use in Weight-Loss Trials: Preliminary Evidence of Validity
Wilson, Kathryn E.; Harden, Samantha M.; Almeida, Fabio A.; You, Wen; Hill, Jennie L.; Goessl, Cody; Estabrooks, Paul A.
2015-01-01
Self-efficacy is a commonly included cognitive variable in weight-loss trials, but there is little uniformity in its measurement. Weight-loss trials frequently focus on physical activity (PA) and eating behavior, as well as weight loss, but no survey is available that offers reliable measurement of self-efficacy as it relates to each of these targeted outcomes. The purpose of this study was to test the psychometric properties of brief, pragmatic self-efficacy scales specific to PA, healthful eating and weight-loss (4 items each). An adult sample (n=1790) from 28 worksites enrolled in a worksite weight-loss program completed the self-efficacy scale, as well as measures of PA, dietary fat intake, and weight, at baseline, 6-, and 12-months. The hypothesized factor structure was tested through confirmatory factor analysis, which supported the expected factor structure for three latent self-efficacy factors, specific to PA, healthful eating, and weight-loss. Measurement equivalence/invariance between relevant demographic groups, and over time was also supported. Parallel growth processes in self-efficacy factors and outcomes (PA, fat intake, and weight) support the predictive validity of score interpretations. Overall, this initial series of psychometric analyses supports the interpretation that scores on these scales reflect self-efficacy for PA, healthful eating, and weight-loss. The use of this instrument in large-scale weight-loss trials is encouraged. PMID:26619093
Pritt, Jeremy J.; Roseman, Edward F.; O'Brien, Timothy P.
2014-01-01
In his seminal work, Hjort (in Fluctuations in the great fisheries of Northern Europe. Conseil Parmanent International Pour L'Exploration De La Mar. Rapports et Proces-Verbaux, 20: 1–228, 1914) observed that fish population levels fluctuated widely, year-class strength was set early in life, and egg production by adults could not alone explain variability in year-class strength. These observations laid the foundation for hypotheses on mechanisms driving recruitment variability in marine systems. More recently, researchers have sought to explain year-class strength of important fish in the Laurentian Great Lakes and some of the hypotheses developed for marine fisheries have been transferred to Great Lakes fish. We conducted a literature review to determine the applicability of marine recruitment hypotheses to Great Lakes fish. We found that temperature, interspecific interactions, and spawner effects (abundance, age, and condition of adults) were the most important factors in explaining recruitment variability in Great Lakes fish, whereas relatively fewer studies identified bottom-up trophodynamic factors or hydrodynamic factors as important. Next, we compared recruitment between Great Lakes and Baltic Sea fish populations and found no statistical difference in factors driving recruitment between the two systems, indicating that recruitment hypotheses may often be transferable between Great Lakes and marine systems. Many recruitment hypotheses developed for marine fish have yet to be applied to Great Lakes fish. We suggest that future research on recruitment in the Great Lakes should focus on forecasting the effects of climate change and invasive species. Further, because the Great Lakes are smaller and more enclosed than marine systems, and have abundant fishery-independent data, they are excellent candidates for future hypothesis testing on recruitment in fish.
Deformational plagiocephaly in normal infants: a systematic review of causes and hypotheses.
De Bock, Freia; Braun, Volker; Renz-Polster, Herbert
2017-06-01
Deformational plagiocephaly (DP) is one of the most prevalent abnormal findings in infants and a frequent reason for parents to seek paediatric advice. To systematically review the literature and identify evidence and hypotheses on the aetiology and determinants of DP in otherwise healthy infants. Systematic keyword search in all major biomedical databases to identify peer-reviewed publications reporting (a) empirical research or (b) hypotheses on the aetiology of DP in healthy, term infants. 3150 studies published between 1985 and 2016 and containing relevant keywords were screened. In a two-pronged approach, results were summarised separately for the body of empirical work (22 studies) and the body of hypotheses (110 articles). Only a few empirical studies have examined risk factors in non-selected patient populations on a higher grade methodological level. The most commonly reported risk factors were: male gender, supine sleep position, limited neck rotation or preference in head position, first-born child, lower level of activity and lack of tummy time. Agreement between empirical studies was poor for most exposures, including supine sleep position, tummy time and use of car seats. The articles reporting hypotheses on the aetiology of DP cover a wide field of environmental and biological factors, but include little suggestions as to the potential influence of the everyday care environment of the baby. The evidence on the aetiology of DP is fragmentary and heterogeneous. In addition, factors possibly relevant to the development of DP have not been appreciated in the scientific discussion. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Djukanovic, Ingrid; Carlsson, Jörg; Årestedt, Kristofer
2017-10-04
The HADS (Hospital Anxiety and Depression Scale) aims to measure symptoms of anxiety (HADS Anxiety) and depression (HADS Depression). The HADS is widely used but has shown ambiguous results both regarding the factor structure and sex differences in the prevalence of depressive symptoms. There is also a lack of psychometric evaluations of the HADS in non-clinical samples of older people. The aim of the study was to evaluate the factor structure of the HADS in a general population 65-80 years old and to exam possible presence of differential item functioning (DIF) with respect to sex. This study was based on data from a Swedish sample, randomized from the total population in the age group 65-80 years (n = 6659). Confirmatory factor analyses (CFA) were performed to examine the factor structure. Ordinal regression analyses were conducted to detect DIF for sex. Reliability was examined by both ordinal as well as traditional Cronbach's alpha. The CFA showed a two-factor model with cross-loadings for two items (7 and 8) had excellent model fit. Internal consistency was good in both subscales, measured with ordinal and traditional alpha. Floor effects were presented for all items. No indication for meaningful DIF regarding sex was found for any of the subscales. HADS Anxiety and HADS Depression are unidimensional measures with acceptable internal consistency and are invariant with regard to sex. Despite pronounced ceiling effects and cross-loadings for item 7 and 8, the hypothesized two-factor model of HADS can be recommended to assess psychological distress among a general population 65-80 years old.
Wagner, J A; Schnoll, R A; Gipson, M T
1998-07-01
Adherence to self-monitoring of blood glucose (SMBG) is problematic for many people with diabetes. Self-reports of adherence have been found to be unreliable, and existing paper-and-pencil measures have limitations. This study developed a brief measure of SMBG adherence with good psychometric properties and a useful factor structure that can be used in research and in practice. A total of 216 adults with diabetes responded to 30 items rated on a 9-point Likert scale that asked about blood monitoring habits. In part I of the study, items were evaluated and retained based on their psychometric properties. The sample was divided into exploratory and confirmatory halves. Using the exploratory half, items with acceptable psychometric properties were subjected to a principal components analysis. In part II of the study, structural equation modeling was used to confirm the component solution with the entire sample. Structural modeling was also used to test the relationship between these components. It was hypothesized that the scale would produce four correlated factors. Principal components analysis suggested a two-component solution, and confirmatory factor analysis confirmed this solution. The first factor measures the degree to which patients rely on others to help them test and thus was named "social influence." The second component measures the degree to which patients use physical symptoms of blood glucose levels to help them test and thus was named "physical influence." Results of the structural model show that the components are correlated and make up the higher-order latent variable adherence. The resulting 15-item scale provides a short, reliable way to assess patient adherence to SMBG. Despite the existence of several aspects of adherence, this study indicates that the construct consists of only two components. This scale is an improvement on previous measures of adherence because of its good psychometric properties, its interpretable factor structure, and its rigorous empirical development.
Tjin A Tsoi, Sharon L N M; de Boer, Anthonius; Croiset, Gerda; Koster, Andries S; van der Burgt, Stéphanie; Kusurkar, Rashmi A
2018-01-31
Insufficient professional development may lead to poor performance of healthcare professionals. Therefore, continuing education (CE) and continuing professional development (CPD) are needed to secure safe and good quality healthcare. The aim of the study was to investigate the hypothesized associations and their directions between pharmacists' basic psychological needs in CE, their academic motivation, well-being, learning outcomes. Self-determination theory was used as a theoretical framework for this study. Data were collected through four questionnaires measuring: academic motivation, basic psychological needs (BPN), vitality and lifelong learning adaptability of pharmacists in the CE/CPD learning context. Structural equation modelling was used to analyze the data. Demographic factors like gender and working environment influenced the observed scores for frustration of BPN and factors like training status and working experience influenced the observed scores for academic motivation. A good model fit could be found only for a part of the hypothesized pathway. Frustration of BPN is positively directly related to the less desirable type of academic motivation, controlled motivation (0.88) and negatively directly related to vitality (- 1.61) and negatively indirectly related to learning outcomes in CE. Fulfillment or frustration of BPN are important predictors for well-being and learning outcomes. Further research should be conducted to discover how we can prevent these needs from being frustrated in order to design a motivating, vitalizing and sustainable CE/CPD system for pharmacists and other healthcare professionals. Basic psychological needs are very important predictors for well-being and learning outcomes. Further research should be conducted to discover how we can prevent these needs from being frustrated in order to design a motivating, vitalizing and sustainable CE/CPD system for pharmacists and other healthcare professionals.
Structural Models that Manage IT Portfolio Affecting Business Value of Enterprise Architecture
NASA Astrophysics Data System (ADS)
Kamogawa, Takaaki
This paper examines the structural relationships between Information Technology (IT) governance and Enterprise Architecture (EA), with the objective of enhancing business value in the enterprise society. Structural models consisting of four related hypotheses reveal the relationship between IT governance and EA in the improvement of business values. We statistically examined the hypotheses by analyzing validated questionnaire items from respondents within firms listed on the Japanese stock exchange who were qualified to answer them. We concluded that firms which have organizational ability controlled by IT governance are more likely to deliver business value based on IT portfolio management.
Konkolÿ Thege, Barna; Rafael, Beatrix; Rohánszky, Magda
2014-01-01
Form C of the Multidimensional Health Locus of Control Scales (MHLC-C) was designed to investigate health-related control beliefs of persons with an existing medical condition. The aim of the present study was to examine the psychometric properties of this instrument in a culture characterized by external control beliefs and learned helplessness—contrary to the societal context of original test development. Altogether, 374 Hungarian patients with cancer, irritable bowel syndrome, diabetes, and cardiovascular and musculoskeletal disorders were enrolled in the study. Besides the MHLC-C, instruments measuring general control beliefs, anxiety, depression, self-efficacy, and health behaviors were also administered to evaluate the validity of the scale. Both exploratory and confirmatory factor analytic techniques were used to investigate the factor structure of the scale. Our results showed that the Hungarian adaptation of the instrument had a slightly different structure than the one originally hypothesized: in the present sample, a three-factor structure emerged where the items of the Doctors and the Others subscales loaded onto a single common component. Internal reliability of all three subscales was adequate (alphas between .71 and .79). Data concerning the instrument's validity were comparable with previous results from Western countries. These findings may suggest that health locus of control can be construed very similarly to Western countries even in a post-communist society—regardless of the potential differences in general control beliefs. PMID:25202967
Research on the Hotel Image Based on the Detail Service
NASA Astrophysics Data System (ADS)
Li, Ban; Shenghua, Zheng; He, Yi
Detail service management, initially developed as marketing programs to enhance customer loyalty, has now become an important part of customer relation strategy. This paper analyzes the critical factors of detail service and its influence on the hotel image. We establish the theoretical model of influencing factors on hotel image and propose corresponding hypotheses. We use applying statistical method to test and verify the above-mentioned hypotheses. This paper provides a foundation for further study of detail service design and planning issues.
Adie, James W; Duda, Joan L; Ntoumanis, Nikos
2008-06-01
Grounded in the 2x2 achievement goal framework (Elliot & McGregor, 2001), a model was tested examining the hypothesized relationships between approach and avoidance (mastery and performance) goals, challenge and threat appraisals of sport competition, and positive and negative indices of well-being (i.e., self-esteem, positive, and negative affect). A further aim was to determine the degree to which the cognitive appraisals mediated the relationship between the four achievement goals and the indicators of athletes' welfare. Finally, measurement and structural invariance was tested with respect to gender in the hypothesized model. An alternative model was also estimated specifying self-esteem as an antecedent of the four goals and cognitive appraisals. Four hundred and twenty-four team sport participants (Mage=24.25) responded to a multisection questionnaire. Structural equation modeling analyses provided support for the hypothesized model only. Challenge and threat appraisals partially mediated the relationships observed between mastery-based goals and the well-being indicators. Lastly, the hypothesized model was found to be invariant across gender.
Itzchakov, Guy; Kluger, Avraham N; Castro, Dotan R
2017-01-01
We examined how listeners characterized by empathy and a non-judgmental approach affect speakers' attitude structure. We hypothesized that high quality listening decreases speakers' social anxiety, which in turn reduces defensive processing. This reduction in defensive processing was hypothesized to result in an awareness of contradictions (increased objective-attitude ambivalence), and decreased attitude extremity. Moreover, we hypothesized that experiencing high quality listening would enable speakers to tolerate contradictory responses, such that listening would attenuate the association between objective- and subjective-attitude ambivalence. We obtained consistent support for our hypotheses across four laboratory experiments that manipulated listening experience in different ways on a range of attitude topics. The effects of listening on objective-attitude ambivalence were stronger for higher dispositional social anxiety and initial objective-attitude ambivalence (Study 4). Overall, the results suggest that speakers' attitude structure can be changed by a heretofore unexplored interpersonal variable: merely providing high quality listening.
Standardization of the NEO-PI-3 in the Greek general population.
Fountoulakis, Konstantinos N; Siamouli, Melina; Moysidou, Stefania; Pantoula, Eleonora; Moutou, Katerina; Panagiotidis, Panagiotis; Kemeridou, Marina; Mavridou, Eirini; Loli, Efimia; Batsiari, Elena; Preti, Antonio; Tondo, Leonardo; Gonda, Xenia; Mobayed, Nisreen; Akiskal, Kareen; Akiskal, Hagop; Costa, Paul; McCrae, Robert
2014-01-01
The revised NEO Personality Inventory (NEO-PI-3) includes 240 items corresponding to the Big Five personality traits (Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to Experience) and subordinate dimensions (facets). It is suitable for use with adolescents and adults (12 years or older). The aim of the current study was to validate the Greek translation of the NEO-PI-3 in the general Greek population. The study sample included 734 subjects from the general Greek population of whom 59.4% were females and 40.6% males aged 40.80 ± 11.48. The NEO-PI-3 was translated into Greek and back-translated into English, and the accuracy of the translation was confirmed and established. The statistical analysis included descriptive statistics, confirmatory factorial analysis (CFA), the calculation of Cronbach's alpha, and the calculation of Pearson product-moment correlations. Sociodemographics groups were compared by ANOVA. Most facets had Cronbach's alpha above 0.60. Confirmatory factor analysis showed acceptable loading of the facets on their own hypothesized factors and very good estimations of Cronbach's alphas for the hypothesized factors, so it was partially supportive of the five-factor structure of the NEO-PI-3.The factors extracted with Procrustes rotation analysis can be considered reasonably homologous to the factors of the American normative sample. Correlations between dimensions were as expected and similar to those reported in the literature. The literature suggests that overall, the psychometric properties of NEO-PI-3 scales have been found to generalize across ages, cultures, and methods of measurement. In accord with this, the results of the current study confirm the reliability of the Greek translation and adaptation of the NEO-PI-3. The inventory has comparable psychometric properties in its Greek version in comparison to the original and other national translations, and it is suitable for clinical as well as research use.
Psychometric Evaluation of the Pain Attitudes Questionnaire-Revised for People With Advanced Cancer.
Mah, Kenneth; Tran, Kim T; Gauthier, Lynn R; Rodin, Gary; Zimmermann, Camilla; Warr, David; Librach, S Lawrence; Moore, Malcolm; Shepherd, Frances A; Gagliese, Lucia
2017-07-01
Pain-related stoicism and cautiousness are theorized to be more prevalent in older than younger patients and to lead to greater pain under-reporting and consequently inadequate pain management in older patients. The Pain Attitudes Questionnaire-Revised (PAQ-R), which measures 5 pain-related stoicism (fortitude, concealment, superiority) and cautiousness (self-doubt, reluctance) factors in chronic pain, can help test this hypothesis in advanced cancer but requires validation. We conducted a psychometric evaluation of the PAQ-R in 155 younger (younger than 60 years) and 114 older (aged 60 years and older) patients with advanced cancer. Participants showed disagreement with self-doubt items and floor effects with the subscale. Confirmatory factor analyses revealed good fit of the PAQ-R's 5 factors to younger and older groups' data but collinearity between fortitude and concealment. Multisample confirmatory factor analyses supported partial scalar invariance between age groups. Few hypothesized age-related differences were observed. Younger patients reported higher superiority scores than older patients. Whereas older patients showed greater fortitude and superiority with lower average pain intensity, younger patients showed greater concealment or fortitude with greater worst and average pain intensity. Furthermore, whereas older patients displayed greater superiority with lower interference in relations with others, younger patients displayed greater concealment and superiority with greater interference in walking ability and greater concealment and self-doubt with more interference in relations with others. Cross-validation of the PAQ-R's factor structure and identification of pathways to the factors and effect on pain-related outcomes using multivariate approaches are warranted. This article presents the psychometric properties of a measure of 2 particular pain-related attitudes. The measure can help clarify whether these attitudes adversely influence pain reporting in older patients with advanced cancer as hypothesized and, in turn, explain the inadequate pain management frequently reported with this clinical group. Copyright © 2017 American Pain Society. Published by Elsevier Inc. All rights reserved.
Fischer, Barbara M; Schatz, Heinrich; Maraun, Mark
2010-11-01
The community structure, stable isotope ratios ((15)N/(14)N, (13)C/(12)C) and reproductive mode of oribatid mites (Acari, Oribatida) were investigated in four habitats (upper tree bark, lower tree bark, dry grassland soil, forest soil) at two sites in the Central Alps (Tyrol, Austria). We hypothesized that community structure and trophic position of oribatid mites of dry grassland soils and bark of trees are similar since these habitats have similar abiotic characteristics (open, dry) compared with forest soil. Further, we hypothesized that derived taxa of oribatid mites reproducing sexually dominate on the bark of trees since species in this habitat consume living resources such as lichens. In contrast to our hypothesis, the community structure of oribatid mites differed among grassland, forest and bark indicating the existence of niche differentiation in the respective oribatid mite species. In agreement with our hypothesis, sexually reproducing taxa of oribatid mites dominated on the bark of trees whereas parthenogenetic species were more frequent in soil. Several species of bark-living oribatid mites had stable isotope signatures that were similar to lichens indicating that they feed on lichens. However, nine species that frequently occurred on tree bark did not feed on lichens according to their stable isotope signatures. No oribatid mite species could be ascribed to moss feeding. We conclude that sexual reproduction served as preadaptation for oribatid mites allowing them to exploit new habitats and new resources on the bark of trees. Abiotic factors likely are of limited importance for bark-living oribatid mites since harsh abiotic conditions are assumed to favor parthenogenesis.
ERIC Educational Resources Information Center
Ortolano, Girolamo; Finn, Julia; Ortolano, Leonard
2017-01-01
In this activity, students learned scientific practices and evidence-based reasoning by formulating and testing hypotheses about factors affecting human reaction time and examining those hypotheses with data from ruler-drop tests. The project aligns with all eight of the science and engineering practices (SEP) embodied in the "Next Generation…
Exploratory factor analysis of the Oral Health Impact Profile.
John, M T; Reissmann, D R; Feuerstahler, L; Waller, N; Baba, K; Larsson, P; Celebić, A; Szabo, G; Rener-Sitar, K
2014-09-01
Although oral health-related quality of life (OHRQoL) as measured by the Oral Health Impact Profile (OHIP) is thought to be multidimensional, the nature of these dimensions is not known. The aim of this report was to explore the dimensionality of the OHIP using the Dimensions of OHRQoL (DOQ) Project, an international study of general population subjects and prosthodontic patients. Using the project's Learning Sample (n = 5173), we conducted an exploratory factor analysis on the 46 OHIP items not specifically referring to dentures for 5146 subjects with sufficiently complete data. The first eigenvalue (27·0) of the polychoric correlation matrix was more than ten times larger than the second eigenvalue (2·6), suggesting the presence of a dominant, higher-order general factor. Follow-up analyses with Horn's parallel analysis revealed a viable second-order, four-factor solution. An oblique rotation of this solution revealed four highly correlated factors that we named Oral Function, Oro-facial Pain, Oro-facial Appearance and Psychosocial Impact. These four dimensions and the strong general factor are two viable hypotheses for the factor structure of the OHIP. © 2014 John Wiley & Sons Ltd.
NASA Technical Reports Server (NTRS)
Reed, G. L.; Matsueda, G. R.; Haber, E.
1992-01-01
Platelet clots resist fibrinolysis by plasminogen activators. We hypothesized that platelet factor XIII may enhance the fibrinolytic resistance of platelet-rich clots by catalyzing the crosslinking of alpha 2-antiplasmin (alpha 2AP) to fibrin. Analysis of plasma clot structure by polyacrylamide gel electrophoresis and immunoblotting revealed accelerated alpha 2AP-fibrin crosslinking in platelet-rich compared with platelet-depleted plasma clots. A similar study of clots formed with purified fibrinogen (depleted of factor XIII activity), isolated platelets, and specific factor XIII inhibitors indicated that this accelerated crosslinking was due to the catalytic activity of platelet factor XIII. Moreover, when washed platelets were aggregated by thrombin, there was evidence of platelet factor XIII-mediated crosslinking between platelet alpha 2AP and platelet fibrin(ogen). Specific inhibition (by a monoclonal antibody) of the alpha 2AP associated with washed platelet aggregates accelerated the fibrinolysis of the platelet aggregate. Thus in platelet-rich plasma clots, and in thrombin-induced platelet aggregates, platelet factor XIII actively formed alpha 2AP-fibrin crosslinks, which appeared to enhance the resistance of platelet-rich clots to fibrinolysis.
Deacon, Nicholas John; Cavender-Bares, Jeannine
2015-01-01
Quercus oleoides Cham. and Schlect., tropical live oak, is a species of conservation importance in its southern range limit of northwestern Costa Rica. It occurs in high-density stands across a fragmented landscape spanning a contrasting elevation and precipitation gradient. We examined genetic diversity and spatial genetic structure in this geographically isolated and genetically distinct population. We characterized population genetic diversity at 11 nuclear microsatellite loci in 260 individuals from 13 sites. We monitored flowering time at 10 sites, and characterized the local environment in order to compare observed spatial genetic structure to hypotheses of isolation-by-distance and isolation-by-environment. Finally, we quantified pollen dispersal distances and tested for local adaptation through a reciprocal transplant experiment in order to experimentally address these hypotheses. High genetic diversity is maintained in the population and the genetic variation is significantly structured among sampled sites. We identified 5 distinct genetic clusters and average pollen dispersal predominately occurred over short distances. Differences among sites in flowering phenology and environmental factors, however, were not strictly associated with genetic differentiation. Growth and survival of upland and lowland progeny in their native and foreign environments was expected to exhibit evidence of local adaptation due to the more extreme dry season in the lowlands. Seedlings planted in the lowland garden experienced much higher mortality than seedlings in the upland garden, but we did not identify evidence for local adaptation. Overall, this study indicates that the Costa Rican Q. oleoides population has a rich population genetic history. Despite environmental heterogeneity and habitat fragmentation, isolation-by-distance and isolation-by-environment alone do not explain spatial genetic structure. These results add to studies of genetic structure by examining a common, tropical tree over multiple habitats and provide information for managers of a successional forest in a protected area.
Family Structure and Adolescent Substance Use: An International Perspective.
Hoffmann, John P
2017-11-10
Numerous studies indicate that family structure is a key correlate of adolescent substance use. Yet there are some important limitations to this research. Studies have been conducted mainly in the United States, with relatively few studies that have compared family structure and youth substance use across nations. There is also a lack of recognition of the complexity of family types prevalent in contemporary global society. Moreover, there remains a need to consider personal, interpersonal, and macro-level characteristics that may help account for the association between family structure and youth substance use. This study uses data from 37 countries to examine several models that purport to explain the association between family structure and substance use. The data are from the 2005-2006 WHO-sponsored Health Behaviour in School-Aged Children (HBSC) (n = 193,202). Multilevel models, including linear, probit, and structural equation models (SEMs), were used to test several hypotheses. The results suggest that time spent with friends largely accounted for the association between specific types of family structures and frequency of alcohol use and getting drunk, but that cannabis use was negatively associated with living with both biological parents irrespective of other factors.
A structural model of treatment program and individual counselor leadership in innovation transfer.
Joe, George W; Becan, Jennifer E; Knight, Danica K; Flynn, Patrick M
2017-03-23
A number of program-level and counselor-level factors are known to impact the adoption of treatment innovations. While program leadership is considered a primary factor, the importance of leadership among clinical staff to innovation transfer is less known. Objectives included explore (1) the influence of two leadership roles, program director and individual counselor, on recent training activity and (2) the relationship of counselor attributes on training endorsement. The sample included 301 clinical staff in 49 treatment programs. A structural equation model was evaluated for key hypothesized relationships between exogenous and endogenous variables related to the two leadership roles. The importance of organizational leadership, climate, and counselor attributes (particularly counseling innovation interest and influence) to recent training activity was supported. In a subset of 68 counselors who attended a developer-led training on a new intervention, it was found that training endorsement was higher among those with high innovation interest and influence. The findings suggest that each leadership level impacts the organization in different ways, yet both can promote or impede technology transfer.
Do (epi)genetics impact the brain in functional neurologic disorders?
Frodl, T
2016-01-01
Advances in neuropsychiatric research are supposed to lead to significant improvements in understanding functional neurologic disorders and their diagnosis. However, epigenetic and genetic research on conversion disorders and somatoform disorders is only at its start. This review demonstrates the current state within this field and tries to bridge a gap from what is known on gene-stress interactions in other psychiatric disorders like depression. The etiology of conversion disorders is hypothesized to be multifactorial. These considerations also suggest that potential etiologic factors lead to alterations in brain function, either episodically or chronically, eventually leading to structural brain changes. In particular, the knowledge of how the environment influences brain structure and function, e.g., via epigenetic regulation, may be interesting for future research in functional neurologic disorders. Reviewing the literature results in evidence that childhood adversities play a role in the development of functional neurologic disorders, whereby at present no reports exist about the interactive effect between childhood adversity and genetic factors or about the impact of epigenetics. © 2016 Elsevier B.V. All rights reserved.
A taxometric study of hypochondriasis symptoms.
Longley, Susan L; Broman-Fulks, Joshua J; Calamari, John E; Noyes, Russell; Wade, Michael; Orlando, Carissa M
2010-12-01
Hypochondriasis has been conceptualized as both a distinct category that is characterized by a disabling illness preoccupation and as a continuum of health concerns. Empirical support for one of these theoretical models will clarify inconsistent assessment approaches and study designs that have impeded theory and research. To facilitate progress, taxometric analyses were conducted to determine whether hypochondriasis is best understood as a discrete category, consistent with the DSM, or as a dimensional entity, consistent with prevailing opinion and most self-report measures. Data from a large undergraduate sample that completed 3 hypochondriasis symptom measures were factor analyzed. The 4 factor analytically derived symptom indicators were then used in these taxometric analyses. Consistent with our hypotheses and existing theory, results supported a dimensional structure for hypochondriasis. Implications for the conceptualization of hypochondriasis and directions for future study are discussed. Copyright © 2010. Published by Elsevier Ltd.
Concepts for the development of light-weight composite structures for rotor burst containment
NASA Technical Reports Server (NTRS)
Holmes, A. G.
1977-01-01
A set of hypotheses is established as to what variables might control the design of a weight-efficient protective device. A particular experiment for evaluating the hypotheses and materials was designed. The design and methods for the analysis of results are described.
An integrated model of feedback-seeking behavior: disposition, context, and cognition.
VandeWalle, D; Ganesan, S; Challagalla, G N; Brown, S P
2000-12-01
This study replicates, integrates, and extends prior research on the dispositional, contextual, and cognitive antecedents of feedback-seeking behavior. Regression analysis was used to analyze data collected from a sample of salespeople (N = 310) from 2 Fortune 500 companies. The study hypotheses were supported with the following results. First, the individual disposition of learning goal orientation and the contextual factors of leader consideration and leader initiation of structure influenced cognitions about the perceived cost and value of feedback seeking. Second, the strength of the relationship of learning goal orientation with the cost and value perceptions was moderated by the leadership style of the supervisor.
Can theories of visual representation help to explain asymmetries in amygdala function?
McMenamin, Brenton W; Marsolek, Chad J
2013-06-01
Emotional processing differs between the left and right hemispheres of the brain, and functional differences have been reported more specifically between the left and right amygdalae, subcortical structures heavily implicated in emotional processing. However, the empirical pattern of amygdalar asymmetries is inconsistent with extant theories of emotional asymmetries. Here we review this discrepancy, and we hypothesize that hemispheric differences in visual object processing help to explain the previously reported functional differences between the left and right amygdalae. The implication that perceptual factors play a large role in determining amygdalar asymmetries may help to explain amygdalar dysfunction in the development and maintenance of posttraumatic stress disorder.
Bayes Factor Approaches for Testing Interval Null Hypotheses
ERIC Educational Resources Information Center
Morey, Richard D.; Rouder, Jeffrey N.
2011-01-01
Psychological theories are statements of constraint. The role of hypothesis testing in psychology is to test whether specific theoretical constraints hold in data. Bayesian statistics is well suited to the task of finding supporting evidence for constraint, because it allows for comparing evidence for 2 hypotheses against each another. One issue…
Beyond edge effects: landscape controls on forest structure in the southeastern US
NASA Astrophysics Data System (ADS)
Fagan, M. E.; Morton, D. C.; Cook, B.; Masek, J. G.; Zhao, F. A.; Nelson, R.; Huang, C.
2016-12-01
The structure of forest canopies (i.e., their height and complexity) is known to be influenced by a variety of factors, including forest age, species composition, disturbance, edaphic and topographical conditions, and exposure to edge environments. The combined impact of each of these factors on canopy structure is not well characterized for most forest ecosystems, however, which limits our ability to predict the regional impacts of forest fragmentation. The objective of this study was to elucidate the main biophysical drivers of canopy structure across two dominant ecosystems in the southeastern U.S: natural mixed deciduous forests, and industrial conifer plantations. We analyzed spatial changes in canopy structure along aerial transects of LiDAR data ( 3,000 km in all). High-resolution (1 m) LiDAR data from Goddard's LiDAR, Hyperspectral, and Thermal Airborne Imager (G-LiHT) were combined with time series of Landsat imagery to quantify forest type, age, composition, and fragmentation. Forest structural metrics (height, gap fraction, and canopy roughness) were examined across forest types, ages, topography, and decreasing edge exposure. We hypothesized that 1) structural edge effects would be weak in both natural and plantation forest types, and 2) age, composition, and topography would be the dominant influences on natural forest structure. We analyzed all large (>4 ha) fragments from the 8562 distinct forests measured during G-LiHT data collections in 2011 across the southeastern U.S. In general, the relationship between forest structural metrics and edge exposure was highly variable in both natural forests and plantations. However, variability in all structural metrics decreased with distance from an edge. Forest age and topography were strong predictors of canopy structure in natural forests. However plantations tended to be located in sites with limited topographical variation, and thinning disturbances of conifer plantations decreased the strength of the age-structure relationship. We found that canopy structure in our region is influenced by edge effects, but other factors played a larger role in determining forest characteristics. Our results highlight the importance of endogenous, stand-specific processes for forest structure, biomass, and biodiversity in the southeastern U.S.
NASA Astrophysics Data System (ADS)
White, Dave D.; Virden, Randy J.; van Riper, Carena J.
2008-10-01
It is generally accepted that recreation use in natural environments results in some degree of negative social and environmental impact. Environmental managers are tasked with mitigating the impact while providing beneficial recreation opportunities. Research on the factors that influence visitors’ perceptions of environmental and social conditions is necessary to inform sound environmental management of protected natural areas. This study examines the effect of prior experience with the setting and two dimensions of place attachment (i.e., place identity and place dependence) on visitors’ perceptions of three types of recreation impacts (i.e., depreciative behavior, environmental impacts, and recreation conflict). Principal components analysis, confirmatory factor analysis, and structural equation modeling were used to test the study hypotheses using data collected from 351 visitors through on-site questionnaires (response rate of 93 percent). The results show that prior experience exhibited a moderate and significant direct positive effect on place identity, place dependence, and visitors’ perceptions of recreation impacts. Contrary to study hypotheses and prior research, neither place dependence nor place identity exhibited a significant effect on the dependent variables. The results show that prior experience causes visitors to be more sensitive to depreciative behaviors, environmental impacts, and recreation conflict. These findings raise concerns over potential visitor displacement and deterioration of site conditions. Implications for resource managers are discussed, which include education, modifying visitor use patterns, and site design strategies.
White, Dave D; Virden, Randy J; van Riper, Carena J
2008-10-01
It is generally accepted that recreation use in natural environments results in some degree of negative social and environmental impact. Environmental managers are tasked with mitigating the impact while providing beneficial recreation opportunities. Research on the factors that influence visitors' perceptions of environmental and social conditions is necessary to inform sound environmental management of protected natural areas. This study examines the effect of prior experience with the setting and two dimensions of place attachment (i.e., place identity and place dependence) on visitors' perceptions of three types of recreation impacts (i.e., depreciative behavior, environmental impacts, and recreation conflict). Principal components analysis, confirmatory factor analysis, and structural equation modeling were used to test the study hypotheses using data collected from 351 visitors through on-site questionnaires (response rate of 93 percent). The results show that prior experience exhibited a moderate and significant direct positive effect on place identity, place dependence, and visitors' perceptions of recreation impacts. Contrary to study hypotheses and prior research, neither place dependence nor place identity exhibited a significant effect on the dependent variables. The results show that prior experience causes visitors to be more sensitive to depreciative behaviors, environmental impacts, and recreation conflict. These findings raise concerns over potential visitor displacement and deterioration of site conditions. Implications for resource managers are discussed, which include education, modifying visitor use patterns, and site design strategies.
How Do Children Restrict Their Linguistic Generalizations? An (Un-)Grammaticality Judgment Study
Ambridge, Ben
2013-01-01
A paradox at the heart of language acquisition research is that, to achieve adult-like competence, children must acquire the ability to generalize verbs into non-attested structures, while avoiding utterances that are deemed ungrammatical by native speakers. For example, children must learn that, to denote the reversal of an action, un- can be added to many verbs, but not all (e.g., roll/unroll; close/*unclose). This study compared theoretical accounts of how this is done. Children aged 5–6 (N = 18), 9–10 (N = 18), and adults (N = 18) rated the acceptability of un- prefixed forms of 48 verbs (and, as a control, bare forms). Across verbs, a negative correlation was observed between the acceptability of ungrammatical un- prefixed forms (e.g., *unclose) and the frequency of (a) the bare form and (b) alternative forms (e.g., open), supporting the entrenchment and pre-emption hypotheses, respectively. Independent ratings of the extent to which verbs instantiate the semantic properties characteristic of a hypothesized semantic cryptotype for un- prefixation were a significant positive predictor of acceptability, for all age groups. The relative importance of each factor differed for attested and unattested un- forms and also varied with age. The findings are interpreted in the context of a new hybrid account designed to incorporate the three factors of entrenchment, pre-emption, and verb semantics. PMID:23252958
Empowering leadership and job crafting: The role of employee optimism.
Thun, Sylvi; Bakker, Arnold B
2018-06-08
The objective of this study was to test the relationship between empowering leadership and job crafting and to examine the moderating role of optimism as a personal resource. We hypothesized that the association between empowering leadership and job crafting would be stronger for employees with high (vs. low) levels of optimism. A total of 331 Norwegian workers from a variety of occupations participated in our study. Results of structural equation modelling analysis generally supported our hypotheses. Empowering leadership was positively related to 3 of the 4 job crafting strategies investigated (increasing structural job resources, increasing social job resources, and increasing challenging job demands; but not reducing hindrance job demands). Moreover, as hypothesized, optimism strengthened the empowering leadership-job crafting relationship for increasing structural resources and increasing challenging demands. The results suggest that empowering leadership is an important antecedent of job crafting strategies, except for reducing hindrance demands. The implications of these findings are discussed. Copyright © 2018 John Wiley & Sons, Ltd.
The gender wealth gap:structural and material constraints and implications for later life.
Denton, Margaret; Boos, Linda
2007-01-01
Wealth is an important measure of economic well-being, because while income captures the current state of inequality, wealth has the potential for examining accumulated and historically structured inequality. This presentation documents the extent of gender inequality in wealth for Canadian women and men aged 45 and older. The analysis uses data from the 1999 Canadian Survey of Financial Security, a large nationally representative survey of household wealth in Canada. Wealth is measured by total net worth as measured by total assets minus debt. We test two general hypotheses to account for gender differences in wealth. The differential exposure hypothesis suggests that women report less wealth accumulation because of their reduced access to the material and social conditions of life that foster economic security. The differential vulnerability hypothesis suggests that women report lower levels of wealth because they receive differential returns to material and social conditions of their lives. Support is found for both hypotheses. Much of the gender differences in wealth can be explained by the gendering of work and family roles that restricts women's ability to build up assets over the life course. But beyond this, there are significant gender interaction effects that indicate that women are further penalized by their returns to participation in family life, their health and where they live. When women do work, net of other factors, they are better able to accumulate wealth than their male counterparts.
Thinking strategies used by Registered Nurses during emergency department triage.
Göransson, Katarina E; Ehnfors, Margareta; Fonteyn, Marsha E; Ehrenberg, Anna
2008-01-01
This paper is a report of a study to describe and compare thinking strategies and cognitive processing in the emergency department triage process by Registered Nurses with high and low triage accuracy. Sound clinical reasoning and accurate decision-making are integral parts of modern nursing practice and are of vital importance during triage in emergency departments. Although studies have shown that individual and contextual factors influence the decisions of Registered Nurses in the triage process, others have failed to explain the relationship between triage accuracy and clinical experience. Furthermore, no study has shown the relationship between Registered Nurses' thinking strategies and their triage accuracy. Using the 'think aloud' method, data were collected in 2004-2005 from 16 RNs working in Swedish emergency departments who had previously participated in a study examining triage accuracy. Content analysis of the data was performed. The Registered Nurses used a variety of thinking strategies, ranging from searching for information, generating hypotheses to stating propositions. They structured the triage process in several ways, beginning by gathering data, generating hypotheses or allocating acuity ratings. Comparison of participants' use of thinking strategies and the structure of the triage process based on their previous triage accuracy revealed only slight differences. The wide range of thinking strategies used by Registered Nurses when performing triage indicates that triage decision-making is complex. Further research is needed to ascertain which skills are most important in triage decision-making.
Yildirim, Bariş O; Derksen, Jan J L
2013-08-01
Since its theoretical inception, psychopathy has been considered by philosophers, clinicians, theorists, and empirical researchers to be substantially and critically explained by genetic factors. In this systematic review and structural analysis, new hypotheses will be introduced regarding gene-gene and gene-environment interactions in the etiology of psychopathy and sociopathy. Theory and research from neurobiological and behavioral sciences will be integrated in order to place this work in a broader conceptual framework and promote synergy across fields. First, a between groups comparison between psychopathy and sociopathy is made based on their specific dysfunctions in emotional processing, behavioral profiles, etiological pathways, HPA-axis functioning, and serotonergic profiles. Next, it is examined how various polymorphisms in serotonergic genes (e.g., TPH, 5HTT, HTR1A, HTR2A, HTR2C, and HTR3) might contribute either individually or interactively to the development of these disorders and through which specific biological and behavioral endophenotypes this effect could be mediated. A short introduction is made into mediating variables such as GABAergic functioning and testosterone which could potentially alter the decisive effect of serotonergic genotypes on behavior and physiology. Finally, critical commentary is presented on how to interpret the hypotheses put forward in this review. Copyright © 2013 Elsevier Ltd. All rights reserved.
Nguyen, Phuong H; Kim, Sunny S; Nguyen, Tuan T; Hajeebhoy, Nemat; Tran, Lan M; Alayon, Silvia; Ruel, Marie T; Rawat, Rahul; Frongillo, Edward A; Menon, Purnima
2016-10-01
The pathways through which behavior change interventions impact breastfeeding practices have not been well studied. This study aimed to examine: (1) the effects of exposure to mass media and interpersonal counseling on exclusive breastfeeding (EBF) and hypothesized psychosocial determinants (i.e. knowledge, intention, beliefs, social norms, and self-efficacy); and (2) the pathways through which exposure to mass media and interpersonal counseling are associated with EBF. We used survey data from mothers with children < 2 year (n = 2045) from the 2013 process evaluation of Alive & Thrive's program in Viet Nam. Multiple linear regression analyses and structural equation modeling were used to estimate effects. Exposure to mass media only, interpersonal counseling only, both or neither was 51%, 5%, 19% and 25%, respectively. Exposure to both mass media and interpersonal counseling had additive effects on EBF as well as on related psychosocial factors, compared with no exposure. For example, EBF prevalence was 26.1 percentage points (pp) higher in the group that received interpersonal counseling only, 3.9 pp higher in the mass media group and 31.8 pp higher in the group that received both interventions. As hypothesized, more than 90% of the total effect of the two interventions on EBF was explained by the psychosocial factors measured. Our findings suggest that combining different behavior change interventions leads to greater changes in psychosocial factors, which in turn positively affects breastfeeding behaviors. © 2016 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
Capitao, Liliana; Sampaio, Adriana; Fernandez, Montse; Sousa, Nuno; Pinheiro, Ana; Goncalves, Oscar F.
2011-01-01
Individuals with Williams syndrome display indiscriminate approach towards strangers. Neuroimaging studies conducted so far have linked this social profile to structural and/or functional abnormalities in WS amygdala and prefrontal cortex. In this study, the neuropsychological hypotheses of amygdala and prefrontal cortex involvement in WS…
Contrasting Microbial Community Assembly Hypotheses: A Reconciling Tale from the Río Tinto
Palacios, Carmen; Zettler, Erik; Amils, Ricardo; Amaral-Zettler, Linda
2008-01-01
Background The Río Tinto (RT) is distinguished from other acid mine drainage systems by its natural and ancient origins. Microbial life from all three domains flourishes in this ecosystem, but bacteria dominate metabolic processes that perpetuate environmental extremes. While the patchy geochemistry of the RT likely influences the dynamics of bacterial populations, demonstrating which environmental variables shape microbial diversity and unveiling the mechanisms underlying observed patterns, remain major challenges in microbial ecology whose answers rely upon detailed assessments of community structures coupled with fine-scale measurements of physico-chemical parameters. Methodology/Principal Findings By using high-throughput environmental tag sequencing we achieved saturation of richness estimators for the first time in the RT. We found that environmental factors dictate the distribution of the most abundant taxa in this system, but stochastic niche differentiation processes, such as mutation and dispersal, also contribute to observed diversity patterns. Conclusions/Significance We predict that studies providing clues to the evolutionary and ecological processes underlying microbial distributions will reconcile the ongoing debate between the Baas Becking vs. Hubbell community assembly hypotheses. PMID:19052647
Contrasting microbial community assembly hypotheses: a reconciling tale from the Río Tinto.
Palacios, Carmen; Zettler, Erik; Amils, Ricardo; Amaral-Zettler, Linda
2008-01-01
The Río Tinto (RT) is distinguished from other acid mine drainage systems by its natural and ancient origins. Microbial life from all three domains flourishes in this ecosystem, but bacteria dominate metabolic processes that perpetuate environmental extremes. While the patchy geochemistry of the RT likely influences the dynamics of bacterial populations, demonstrating which environmental variables shape microbial diversity and unveiling the mechanisms underlying observed patterns, remain major challenges in microbial ecology whose answers rely upon detailed assessments of community structures coupled with fine-scale measurements of physico-chemical parameters. By using high-throughput environmental tag sequencing we achieved saturation of richness estimators for the first time in the RT. We found that environmental factors dictate the distribution of the most abundant taxa in this system, but stochastic niche differentiation processes, such as mutation and dispersal, also contribute to observed diversity patterns. We predict that studies providing clues to the evolutionary and ecological processes underlying microbial distributions will reconcile the ongoing debate between the Baas Becking vs. Hubbell community assembly hypotheses.
Unifying the aspects of the Big Five, the interpersonal circumplex, and trait affiliation.
DeYoung, Colin G; Weisberg, Yanna J; Quilty, Lena C; Peterson, Jordan B
2013-10-01
Two dimensions of the Big Five, Extraversion and Agreeableness, are strongly related to interpersonal behavior. Factor analysis has indicated that each of the Big Five contains two separable but related aspects. The present study examined the manner in which the aspects of Extraversion (Assertiveness and Enthusiasm) and Agreeableness (Compassion and Politeness) relate to interpersonal behavior and trait affiliation, with the hypothesis that these four aspects have a structure corresponding to the octants of the interpersonal circumplex. A second hypothesis was that measures of trait affiliation would fall between Enthusiasm and Compassion in the IPC. These hypotheses were tested in three demographically different samples (N = 469; 294; 409) using both behavioral frequency and trait measures of the interpersonal circumplex, in conjunction with the Big Five Aspect Scales (BFAS) and measures of trait affiliation. Both hypotheses were strongly supported. These findings provide a more thorough and precise mapping of the interpersonal traits within the Big Five and support the integration of the Big Five with models of interpersonal behavior and trait affiliation. © 2012 Wiley Periodicals, Inc.
Bardenheier, Barbara H; Bullard, Kai McKeever; Caspersen, Carl J; Cheng, Yiling J; Gregg, Edward W; Geiss, Linda S
2013-09-01
To use structural modeling to test a hypothesized model of causal pathways related with prediabetes among older adults in the U.S. Cross-sectional study of 2,230 older adults (≥ 50 years) without diabetes included in the morning fasting sample of the 2001-2006 National Health and Nutrition Examination Surveys. Demographic data included age, income, marital status, race/ethnicity, and education. Behavioral data included physical activity (metabolic equivalent hours per week for vigorous or moderate muscle strengthening, walking/biking, and house/yard work), and poor diet (refined grains, red meat, added sugars, solid fats, and high-fat dairy). Structural-equation modeling was performed to examine the interrelationships among these variables with family history of diabetes, high blood pressure, BMI, large waist (waist circumference: women, ≥ 35 inches; men, ≥ 40 inches), triglycerides ≥ 200 mg/dL, and total and HDL (≥ 60 mg/dL) cholesterol. After dropping BMI and total cholesterol, our best-fit model included three single factors: socioeconomic position (SEP), physical activity, and poor diet. Large waist had the strongest direct effect on prediabetes (0.279), followed by male sex (0.270), SEP (-0.157), high blood pressure (0.122), family history of diabetes (0.070), and age (0.033). Physical activity had direct effects on HDL (0.137), triglycerides (-0.136), high blood pressure (-0.132), and large waist (-0.067); poor diet had direct effects on large waist (0.146) and triglycerides (0.148). Our results confirmed that, while including factors known to be associated with high risk of developing prediabetes, large waist circumference had the strongest direct effect. The direct effect of SEP on prediabetes suggests mediation by some unmeasured factor(s).
2013-01-01
Background Two of the current methodological barriers to implementation science efforts are the lack of agreement regarding constructs hypothesized to affect implementation success and identifiable measures of these constructs. In order to address these gaps, the main goals of this paper were to identify a multi-level framework that captures the predominant factors that impact implementation outcomes, conduct a systematic review of available measures assessing constructs subsumed within these primary factors, and determine the criterion validity of these measures in the search articles. Method We conducted a systematic literature review to identify articles reporting the use or development of measures designed to assess constructs that predict the implementation of evidence-based health innovations. Articles published through 12 August 2012 were identified through MEDLINE, CINAHL, PsycINFO and the journal Implementation Science. We then utilized a modified five-factor framework in order to code whether each measure contained items that assess constructs representing structural, organizational, provider, patient, and innovation level factors. Further, we coded the criterion validity of each measure within the search articles obtained. Results Our review identified 62 measures. Results indicate that organization, provider, and innovation-level constructs have the greatest number of measures available for use, whereas structural and patient-level constructs have the least. Additionally, relatively few measures demonstrated criterion validity, or reliable association with an implementation outcome (e.g., fidelity). Discussion In light of these findings, our discussion centers on strategies that researchers can utilize in order to identify, adapt, and improve extant measures for use in their own implementation research. In total, our literature review and resulting measures compendium increases the capacity of researchers to conceptualize and measure implementation-related constructs in their ongoing and future research. PMID:23414420
The role of personality in predicting drug and alcohol use among sexual minorities.
Livingston, Nicholas A; Oost, Kathryn M; Heck, Nicholas C; Cochran, Bryan N
2015-06-01
Research consistently demonstrates that sexual minority status is associated with increased risk of problematic substance use. Existing literature in this area has focused on group-specific minority stress factors (e.g., victimization and internalized heterosexism). However, no known research has tested the incremental validity of personality traits as predictors of substance use beyond identified group-specific risk factors. A sample of 704 sexual minority adults was recruited nationally from lesbian, gay, bisexual, transgender, queer, and questioning community organizations and social networking Web sites and asked to complete an online survey containing measures of personality, sexual minority stress, and substance use. Hierarchical regression models were constructed to test the incremental predictive validity of five-factor model personality traits over and above known sexual minority risk factors. Consistent with hypotheses, extraversion and conscientiousness were associated with drug and alcohol use after accounting for minority stress factors, and all factors except agreeableness were associated with substance use at the bivariate level of analysis. Future research should seek to better understand the role of normal personality structures and processes conferring risk for substance use among sexual minorities. (PsycINFO Database Record (c) 2015 APA, all rights reserved).
Sources of stress, burnout and intention to terminate among rugby union referees.
Rainey, D W; Hardy, L
1999-10-01
We examined sources of stress, burnout and intention to terminate among rugby union referees. Questionnaires were returned by 682 of 1175 referees (58%) from Wales, Scotland and England. Exploratory and confirmatory factor analyses revealed four correlated sources of stress factors (performance concerns, time pressure, interpersonal conflict and fear of physical harm), which accounted for 49.6% of the variance. Referees believed the first three factors to be mildly related to their stress. They believed fear of physical harm to be unrelated to their stress. A structural model hypothesizing that time pressure and interpersonal conflict predict burnout, and that age and burnout predict intention to terminate refereeing, fit the observed data. The goodness-of-fit index for this model was 0.96. Our results and those of other studies indicate that interpersonal conflict and time pressure are common sources of stress for sport officials and are frequently related to their burnout experiences. Also, age and burnout are frequently, although only marginally, related to intention to terminate.
Trompette, Justine; Kivits, Joëlle; Minary, Laetitia; Cambon, Linda; Alla, François
2014-11-04
The effects of health promotion interventions are the result not only of the interventions themselves, but also of the contexts in which they unfold. The objective of this study was to analyze, through stakeholders' discourse, the characteristics of an intervention that can influence its outcomes. This case study was based on semi-structured interviews with health promotion stakeholders involved in a regional program (PRALIMAP). General hypotheses on transferability and on how the intervention is presumed to produce its effects were used to construct an interview guide. Interviews were analyzed using thematic coding. Twenty-three stakeholders were interviewed. Results showed stakeholders made few references to population and environment characteristics. Three themes emerged as significant for the stakeholders: implementation modalities and methodology, modalities used to mobilize actors; and transferability-promoting factors and barriers. Our work contributes to a better understanding not only of transferability factors, but also of stakeholders' perceptions of them, which are just as important, because those perceptions themselves are a factor in mobilization of actors, implementation, and transferability.
Family obligation values as a protective and vulnerability factor among low-income adolescent girls.
Milan, Stephanie; Wortel, Sanne
2015-06-01
Adolescents' beliefs about family obligation often reflect cultural variations in their family context, and thus are important for understanding development among diverse youth. In this study, we test hypotheses about the role of family obligation values in risk behavior and mental health in a sample of 194 low-income adolescent girls (mean age = 15.2; 58% Latina, 28% African-American/Black). We hypothesized that family obligation values can be both a protective and vulnerability factor, depending on the type of outcome and the presence of other risk factors. Across the sample, higher family obligation values tended to occur with indicators of positive family functioning (e.g., more frequent communication, less maternal hostility) based on mother and adolescent reports. As hypothesized, family obligation values moderated the relationship between established risk factors and adjustment in distinct ways, such that high family obligation values decreased risk in some domains (i.e., a protective factor) but increased risk in other domains (i.e., a vulnerability factor). Specifically, high family obligation values diminished the relationship between peer norms for risky behavior (sex and substance use) and individual engagement in those behaviors. At the same time, high family obligation values magnified the relationship between exposure to negative life events and poor mental health (PTSD and depressive symptoms). The results suggest that family obligation is an important but complex aspect of development among diverse adolescent girls.
Ideological change in nuclear witnesses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garcia-Bahne, B.
1985-01-01
This research examines factors associated with atomic veterans maintaining or changing their ideology in relation to their radiation exposure as a function of having witnessed nuclear weapons testing. The study also examined inconsistency (incongruence between physician ratings of self-reported symptoms and perceived health), and current attitudes towards the government. Data were collected with atomic veterans through 16 interviews and a questionnaire with 128 respondents. Three hypotheses were formulated. (1) Ideological change is associated with a high need for structure and high openness; low ideological change with low openness and a high need for structure. Findings failed to substantially support thismore » hypothesis. (2) High ideological change is associated with a high need for structure and high acknowledgement; least ideological change, with a high need for structure and low acknowledgement. Findings failed to substantially support this hypothesis. (3) High ideological change and a high need for structure are both expected with high openness and inconsistency. Low ideological change and a high need for structure are associated with low openness and inconsistency. Current faith in the government is associated with low openness and inconsistency. Findings confirmed the third part. Trends and significant supplementary variables are discussed.« less
Reddan, Jeffery M.; White, David J.; Macpherson, Helen; Scholey, Andrew; Pipingas, Andrew
2018-01-01
Modifying nutritional intake through supplementation may be efficacious for altering the trajectory of cerebral structural decline evident with increasing age. To date, there have been a number of clinical trials in older adults whereby chronic supplementation with B vitamins, omega-3 fatty acids, or resveratrol, has been observed to either slow the rate of decline or repair cerebral tissue. There is also some evidence from animal studies indicating that supplementation with glycerophospholipids (GPL) may benefit cerebral structure, though these effects have not yet been investigated in adult humans. Despite this paucity of research, there are a number of factors predicting poorer cerebral structure in older humans, which GPL supplementation appears to beneficially modify or protect against. These include elevated concentrations of homocysteine, unbalanced activity of reactive oxygen species both increasing the risk of oxidative stress, increased concentrations of pro-inflammatory messengers, as well as poorer cardio- and cerebrovascular function. As such, it is hypothesized that GPL supplementation will support cerebral structure in older adults. These cerebral effects may influence cognitive function. The current review aims to provide a theoretical basis for future clinical trials investigating the effects of GPL supplementation on cerebral structural integrity in older adults. PMID:29563868
Spence Laschinger, Heather K; Fida, Roberta
2015-05-01
A model linking authentic leadership, structural empowerment, and supportive professional practice environments to nurses' perceptions of patient care quality and job satisfaction was tested. Positive work environment characteristics are important for nurses' perceptions of patient care quality and job satisfaction (significant factors for retention). Few studies have examined the mechanism by which these characteristics operate to influence perceptions of patient care quality or job satisfaction. A cross-sectional provincial survey of 723 Canadian nurses was used to test the hypothesized models using structural equation modeling. The model was an acceptable fit and all paths were significant. Authentic leadership had a positive effect on structural empowerment, which had a positive effect on perceived support for professional practice and a negative effect on nurses' perceptions that inadequate unit staffing prevented them from providing high-quality patient care. These workplace conditions predicted job satisfaction. Authentic leaders play an important role in creating empowering professional practice environments that foster high-quality care and job satisfaction.
WAIS-IV subtest covariance structure: conceptual and statistical considerations.
Ward, L Charles; Bergman, Maria A; Hebert, Katina R
2012-06-01
D. Wechsler (2008b) reported confirmatory factor analyses (CFAs) with standardization data (ages 16-69 years) for 10 core and 5 supplemental subtests from the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV). Analyses of the 15 subtests supported 4 hypothesized oblique factors (Verbal Comprehension, Working Memory, Perceptual Reasoning, and Processing Speed) but also revealed unexplained covariance between Block Design and Visual Puzzles (Perceptual Reasoning subtests). That covariance was not included in the final models. Instead, a path was added from Working Memory to Figure Weights (Perceptual Reasoning subtest) to improve fit and achieve a desired factor pattern. The present research with the same data (N = 1,800) showed that the path from Working Memory to Figure Weights increases the association between Working Memory and Matrix Reasoning. Specifying both paths improves model fit and largely eliminates unexplained covariance between Block Design and Visual Puzzles but with the undesirable consequence that Figure Weights and Matrix Reasoning are equally determined by Perceptual Reasoning and Working Memory. An alternative 4-factor model was proposed that explained theory-implied covariance between Block Design and Visual Puzzles and between Arithmetic and Figure Weights while maintaining compatibility with WAIS-IV Index structure. The proposed model compared favorably with a 5-factor model based on Cattell-Horn-Carroll theory. The present findings emphasize that covariance model comparisons should involve considerations of conceptual coherence and theoretical adherence in addition to statistical fit. (c) 2012 APA, all rights reserved
Vaingankar, Janhavi Ajit; Subramaniam, Mythily; Abdin, Edimansyah; Picco, Louisa; Chua, Boon Yiang; Eng, Goi Khia; Sambasivam, Rajeswari; Shafie, Saleha; Zhang, Yunjue; Chong, Siow Ann
2014-06-01
The 47-item positive mental health (PMH) instrument measures the level of PMH in multiethnic adult Asian populations. This study aimed to (1) develop a short PMH instrument and (2) establish its validity and reliability among the adult Singapore population. Two separate studies were conducted among adult community-dwelling Singapore residents of Chinese, Malay or Indian ethnicity where participants completed self-administered questionnaires. In the first study, secondary data analysis was conducted using confirmatory factor analysis (CFA) to shorten the PMH instrument. In the second study, the newly developed short PMH instrument and other scales were administered to 201 residents to establish its factor structure, validity and reliability. A 20-item short PMH instrument fulfilling a higher-order six-factor structure was developed following secondary analysis. The mean age of the participants in the second study was 41 years and about 53% were women. One item with poor factor loading was further removed to generate a 19-item version of the PMH instrument. CFA demonstrated a first-order six-factor model of the short PMH instrument. The PMH-19 instrument and its subscales fulfilled criterion validity hypotheses. Internal consistency and test-retest reliability of the PMH-19 instrument were high (Cronbach's α coefficient = 0.87; intraclass correlation coefficient = 0.93, respectively). The 19-item PMH instrument is multidimensional, valid and reliable, and most importantly, with its reduced administration time, the short PMH instrument can be used to measure and evaluate PMH in Asian communities.
Cross-cultural differences in driving skills: a comparison of six countries.
Ozkan, Türker; Lajunen, Timo; Chliaoutakis, Joannes El; Parker, Dianne; Summala, Heikki
2006-09-01
The first aim of the present study was to investigate the applicability of the two-factor structure (perceptual-motor skills by 11 items, e.g., "fluent driving"; safety skills by 9 items, e.g., "conforming to the speed limits") of the Driver Skill Inventory (DSI) among British, Dutch, Finnish, Greek, Iranian, and Turkish drivers. It was also hypothesized that the combination of self reported high ratings of perceptual-motor skills and low ratings of safety skills creates a serious risk for dangerous driving and road accident involvement. The second aim of this study was, therefore, to investigate this asymmetric relationship between perceptual-motor and safety skills in traffic penalties and accident involvement. Two hundred and forty two drivers were chosen from each of the six countries, matched for age and sex. The results of exploratory factor analyses together with target rotation showed that the two-factor structure of DSI found in "safe" Northern and Western European countries were highly congruent. However, the safety skills factor of DSI in Greece, Iran, and Turkey was relatively incongruent in spite of high factor similarity found in perceptual-motor skills. The asymmetric relationship between perceptual-motor and safety skills on traffic penalties was found in Finland and Turkey. A negative relationship between safety skills and the number of accidents was found both in Greece and Iran while a positive relationship between perceptual-motor skills and the number of accidents was found only in Iran.
Influence of syllable structure on L2 auditory word learning.
Hamada, Megumi; Goya, Hideki
2015-04-01
This study investigated the role of syllable structure in L2 auditory word learning. Based on research on cross-linguistic variation of speech perception and lexical memory, it was hypothesized that Japanese L1 learners of English would learn English words with an open-syllable structure without consonant clusters better than words with a closed-syllable structure and consonant clusters. Two groups of college students (Japanese group, N = 22; and native speakers of English, N = 21) learned paired English pseudowords and pictures. The pseudoword types differed in terms of the syllable structure and consonant clusters (congruent vs. incongruent) and the position of consonant clusters (coda vs. onset). Recall accuracy was higher for the pseudowords in the congruent type and the pseudowords with the coda-consonant clusters. The syllable structure effect was obtained from both participant groups, disconfirming the hypothesized cross-linguistic influence on L2 auditory word learning.
Molecular Mechanisms and New Treatment Paradigm for Atrial Fibrillation.
Sirish, Padmini; Li, Ning; Timofeyev, Valeriy; Zhang, Xiao-Dong; Wang, Lianguo; Yang, Jun; Lee, Kin Sing Stephen; Bettaieb, Ahmed; Ma, Sin Mei; Lee, Jeong Han; Su, Demetria; Lau, Victor C; Myers, Richard E; Lieu, Deborah K; López, Javier E; Young, J Nilas; Yamoah, Ebenezer N; Haj, Fawaz; Ripplinger, Crystal M; Hammock, Bruce D; Chiamvimonvat, Nipavan
2016-05-01
Atrial fibrillation represents the most common arrhythmia leading to increased morbidity and mortality, yet, current treatment strategies have proven inadequate. Conventional treatment with antiarrhythmic drugs carries a high risk for proarrhythmias. The soluble epoxide hydrolase enzyme catalyzes the hydrolysis of anti-inflammatory epoxy fatty acids, including epoxyeicosatrienoic acids from arachidonic acid to the corresponding proinflammatory diols. Therefore, the goal of the study is to directly test the hypotheses that inhibition of the soluble epoxide hydrolase enzyme can result in an increase in the levels of epoxyeicosatrienoic acids, leading to the attenuation of atrial structural and electric remodeling and the prevention of atrial fibrillation. For the first time, we report findings that inhibition of soluble epoxide hydrolase reduces inflammation, oxidative stress, atrial structural, and electric remodeling. Treatment with soluble epoxide hydrolase inhibitor significantly reduces the activation of key inflammatory signaling molecules, including the transcription factor nuclear factor κ-light-chain-enhancer, mitogen-activated protein kinase, and transforming growth factor-β. This study provides insights into the underlying molecular mechanisms leading to atrial fibrillation by inflammation and represents a paradigm shift from conventional antiarrhythmic drugs, which block downstream events to a novel upstream therapeutic target by counteracting the inflammatory processes in atrial fibrillation. © 2016 American Heart Association, Inc.
Knowledge of Global Climate Change: View of Iranian University Students
ERIC Educational Resources Information Center
Salehi, Sadegh; Nejad, Zahra Pazuki; Mahmoudi, Hossein; Burkart, Stefan
2016-01-01
This article assesses students' understanding of global climate change (GCC) and social factors affecting it. It was hypothesized that students who demonstrate pro-environmental attitudes are more likely to possess higher knowledge of GCC. It was further hypothesized that trust and personal efficiency would have a positive effect on the knowledge…
A Structural Equation Model on Korean Adolescents' Excessive Use of Smartphones.
Lee, Hana; Kim, JooHyun
2018-03-31
We develop a unified structural model that defines multi-relationships between systematic factors causing excessive use of smartphones and the corresponding results. We conducted a survey with adolescents who live in Seoul, Pusan, Gangneung, Donghae, and Samcheok from Feb. to Mar. 2016. We utilized SPSS Ver. 22 and Amos Ver. 22 to analyze the survey result at a 0.05 significance level. To investigate demographic characteristics of the participants and their variations, we employed descriptive analysis. We adopted the maximum likelihood estimate method to verify the fitness of the hypothetical model and the hypotheses therein. We used χ 2 statistics, GFI, AGFI, CFI, NFI, IFI, RMR, and RMSEA to verify the fitness of our structural model. (1) Our proposed structural model demonstrated a fine fitness level. (2) Our proposed structural model could describe the excessive use of a smartphone with 88.6% accuracy. (3) The absence of the family function and relationship between friends, impulsiveness, and low self-esteem were confirmed as key factors that cause excessive use of smartphones. (4) Further, impulsiveness and low self-esteem are closely related to the absence of family functions and relations between friends by 68.3% and 54.4%, respectively. We suggest that nursing intervention programs from various angles are required to reduce adolescents' excessive use of smartphones. For example, family communication programs would be helpful for both parents and children. Consultant programs about friend relationship also meaningful for the program. Copyright © 2018. Published by Elsevier B.V.
Secondary flow structure in a model curved artery: 3D morphology and circulation budget analysis
NASA Astrophysics Data System (ADS)
Bulusu, Kartik V.; Plesniak, Michael W.
2015-11-01
In this study, we examined the rate of change of circulation within control regions encompassing the large-scale vortical structures associated with secondary flows, i.e. deformed Dean-, Lyne- and Wall-type (D-L-W) vortices at planar cross-sections in a 180° curved artery model (curvature ratio, 1/7). Magnetic resonance velocimetry (MRV) and particle image velocimetry (PIV) experiments were performed independently, under the same physiological inflow conditions (Womersley number, 4.2) and using Newtonian blood-analog fluids. The MRV-technique performed at Stanford University produced phase-averaged, three-dimensional velocity fields. Secondary flow field comparisons of MRV-data to PIV-data at various cross-sectional planes and inflow phases were made. A wavelet-decomposition-based approach was implemented to characterize various secondary flow morphologies. We hypothesize that the persistence and decay of arterial secondary flow vortices is intrinsically related to the influence of the out-of-plane flow, tilting, in-plane convection and diffusion-related factors within the control regions. Evaluation of these factors will elucidate secondary flow structures in arterial hemodynamics. Supported by the National Science Foundation under Grant Number CBET-0828903, and GW Center for Biomimetics and Bioinspired Engineering (COBRE). The MRV data were acquired at Stanford University in collaboration with Christopher Elkins and John Eaton.
Structure and Relaxation in Solutions of Monoclonal Antibodies.
Wang, Gang; Varga, Zsigmond; Hofmann, Jennifer; Zarraga, Isidro E; Swan, James W
2018-03-22
Reversible self-association of therapeutic antibodies is a key factor in high protein solution viscosities. In the present work, a coarse-grained computational model accounting for electrostatic, dispersion, and long-ranged hydrodynamic interactions of two model monoclonal antibodies is applied to understand the nature of self-association, predicting the solution microstructure and resulting transport properties of the solution. For the proteins investigated, the structure factor across a range of solution conditions shows quantitative agreement with neutron-scattering experiments. We observe a homogeneous, dynamical association of the antibodies with no evidence of phase separation. Calculations of self-diffusivity and viscosity from coarse-grained dynamic simulations show the appropriate trends with concentration but, respectively, over- and under-predict the experimentally measured values. By adding constraints to the self-associated clusters that rigidify them under flow, prediction of the transport properties is significantly improved with respect to experimental measurements. We hypothesize that these rigidity constraints are associated with missing degrees of freedom in the coarse-grained model resulting from patchy and heterogeneous interactions among coarse-grained domains. These results demonstrate how structural anisotropy and anisotropy of interactions generated by features at the 2-5 nm length scale in antibodies are sufficient to recover the dynamics and rheological properties of these important macromolecular solutions.
Tremblay, Marlène; Crim, Stacy M; Cole, Dana J; Hoekstra, Robert M; Henao, Olga L; Döpfer, Dörte
2017-10-01
The Foodborne Diseases Active Surveillance Network (FoodNet) is currently using a negative binomial (NB) regression model to estimate temporal changes in the incidence of Campylobacter infection. FoodNet active surveillance in 483 counties collected data on 40,212 Campylobacter cases between years 2004 and 2011. We explored models that disaggregated these data to allow us to account for demographic, geographic, and seasonal factors when examining changes in incidence of Campylobacter infection. We hypothesized that modeling structural zeros and including demographic variables would increase the fit of FoodNet's Campylobacter incidence regression models. Five different models were compared: NB without demographic covariates, NB with demographic covariates, hurdle NB with covariates in the count component only, hurdle NB with covariates in both zero and count components, and zero-inflated NB with covariates in the count component only. Of the models evaluated, the nonzero-augmented NB model with demographic variables provided the best fit. Results suggest that even though zero inflation was not present at this level, individualizing the level of aggregation and using different model structures and predictors per site might be required to correctly distinguish between structural and observational zeros and account for risk factors that vary geographically.
2011-01-01
Background Although many biological databases are applying semantic web technologies, meaningful biological hypothesis testing cannot be easily achieved. Database-driven high throughput genomic hypothesis testing requires both of the capabilities of obtaining semantically relevant experimental data and of performing relevant statistical testing for the retrieved data. Tissue Microarray (TMA) data are semantically rich and contains many biologically important hypotheses waiting for high throughput conclusions. Methods An application-specific ontology was developed for managing TMA and DNA microarray databases by semantic web technologies. Data were represented as Resource Description Framework (RDF) according to the framework of the ontology. Applications for hypothesis testing (Xperanto-RDF) for TMA data were designed and implemented by (1) formulating the syntactic and semantic structures of the hypotheses derived from TMA experiments, (2) formulating SPARQLs to reflect the semantic structures of the hypotheses, and (3) performing statistical test with the result sets returned by the SPARQLs. Results When a user designs a hypothesis in Xperanto-RDF and submits it, the hypothesis can be tested against TMA experimental data stored in Xperanto-RDF. When we evaluated four previously validated hypotheses as an illustration, all the hypotheses were supported by Xperanto-RDF. Conclusions We demonstrated the utility of high throughput biological hypothesis testing. We believe that preliminary investigation before performing highly controlled experiment can be benefited. PMID:21342584
Hoben, Matthias; Estabrooks, Carole A.; Squires, Janet E.; Behrens, Johann
2016-01-01
We translated the Canadian residential long term care versions of the Alberta Context Tool (ACT) and the Conceptual Research Utilization (CRU) Scale into German, to study the association between organizational context factors and research utilization in German nursing homes. The rigorous translation process was based on best practice guidelines for tool translation, and we previously published methods and results of this process in two papers. Both instruments are self-report questionnaires used with care providers working in nursing homes. The aim of this study was to assess the factor structure, reliability, and measurement invariance (MI) between care provider groups responding to these instruments. In a stratified random sample of 38 nursing homes in one German region (Metropolregion Rhein-Neckar), we collected questionnaires from 273 care aides, 196 regulated nurses, 152 allied health providers, 6 quality improvement specialists, 129 clinical leaders, and 65 nursing students. The factor structure was assessed using confirmatory factor models. The first model included all 10 ACT concepts. We also decided a priori to run two separate models for the scale-based and the count-based ACT concepts as suggested by the instrument developers. The fourth model included the five CRU Scale items. Reliability scores were calculated based on the parameters of the best-fitting factor models. Multiple-group confirmatory factor models were used to assess MI between provider groups. Rather than the hypothesized ten-factor structure of the ACT, confirmatory factor models suggested 13 factors. The one-factor solution of the CRU Scale was confirmed. The reliability was acceptable (>0.7 in the entire sample and in all provider groups) for 10 of 13 ACT concepts, and high (0.90–0.96) for the CRU Scale. We could demonstrate partial strong MI for both ACT models and partial strict MI for the CRU Scale. Our results suggest that the scores of the German ACT and the CRU Scale for nursing homes are acceptably reliable and valid. However, as the ACT lacked strict MI, observed variables (or scale scores based on them) cannot be compared between provider groups. Rather, group comparisons should be based on latent variable models, which consider the different residual variances of each group. PMID:27656156
Assessment of Magical Beliefs about Food and Health.
Lindeman, M; Keskivaara, P; Roschier, M
2000-03-01
The Magical Beliefs About Food and Health scale (MFH) was developed to assess individual differences in the tendency to adopt eating and health instructions that many magazines, health care books and food ideologies regard as valid but which obey universal laws of similarity and contagion. In a study of 216 individuals, the total MFH score showed good internal consistency and it was associated with various validity criteria as hypothesized (e.g. vegetarianism and other ideological commitments to food choice, female gender, increased neuroticism, experiential thinking, positive attitudes towards alternative medicine, low sensation seeking and endorsement of universalism values). Factor analysis yielded two factors: General Magical Beliefs and Animal Products as Food Contaminants. In addition, three other items (the Animal Products as Personality Contaminants scale) cross-loaded on the two factors. The factor structure and test-retest reliability were confirmed with separate samples. The results showed that the total MFH score is a reliable and valid measure of magical food and health beliefs, and that the subscales may prove useful when a multidimensional assessment of magical beliefs is needed.
Reproductive and hormonal risk factors of breast cancer: a historical perspective.
Horn, Julie; Vatten, Lars J
2017-01-01
The complexity of breast cancer etiology has puzzled scientists for more than 300 years. In this brief review, we emphasize the importance of reproductive and hormonal factors in relation to the risk of breast cancer. By following the historical course of how various risk factors have been determined, this study attempts to illustrate the origin of hypotheses, their subsequent rejection, and development of new hypotheses. Starting with the contributions of Italian physicians in the 18th century and covering the activity of British epidemiologists before World War II, this review ends up with the international collaboration that became increasingly important in the second half of the 20th century.
Contractor, Ateka A; Durham, Tory A; Brennan, Julie A; Armour, Cherie; Wutrick, Hanna R; Frueh, B Christopher; Elhai, Jon D
2014-01-30
Existing literature indicates significant comorbidity between posttraumatic stress disorder (PTSD) and major depression. We examined whether PTSD's dysphoria and mood/cognitions factors, conceptualized by the empirically supported four-factor DSM-5 PTSD models, account for PTSD's inherent relationship with depression. We hypothesized that depression's somatic and non-somatic factors would be more related to PTSD's dysphoria and mood/cognitions factors than other PTSD model factors. Further, we hypothesized that PTSD's arousal would significantly mediate relations between PTSD's dysphoria and somatic/non-somatic depression. Using 181 trauma-exposed primary care patients, confirmatory factor analyses (CFA) indicated a well-fitting DSM-5 PTSD dysphoria model, DSM-5 numbing model and two-factor depression model. Both somatic and non-somatic depression factors were more related to PTSD's dysphoria and mood/cognitions factors than to re-experiencing and avoidance factors; non-somatic depression was more related to PTSD's dysphoria than PTSD's arousal factor. PTSD's arousal did not mediate the relationship between PTSD's dysphoria and somatic/non-somatic depression. Implications are discussed. © 2013 Published by Elsevier Ireland Ltd.
NASA Technical Reports Server (NTRS)
Chafin, R. L.; Martin, T. H.
1980-01-01
The project plan was to hold focus groups to identify the factors influencing the ease of use characteristics of software and to bond the problem. A questionnaire survey was conducted to evaluate those factors which were more appropriately measured with that method. The performance oriented factors were analyzed and relationships hypothesized. The hypotheses were put to test in the experimental phase of the project. In summary, the initial analysis indicates that there is an initial performance effect favoring computer controlled dialogue but the advantage fades fast as operators become experienced. The user documentation style is seen to have a significant effect on performance. The menu and prompt command formats are preferred by inexperienced operators. The short form mnemonic is least favored. There is no clear best command format but the short form mnemonic is clearly the worst.
Without Specifiers: Phrase Structure and Events
ERIC Educational Resources Information Center
Lohndal, Terje
2012-01-01
This dissertation attempts to unify two reductionist hypotheses: that there is no relational difference between specifiers and complements, and that verbs do not have thematic arguments. I argue that these two hypotheses actually bear on each other and that we get a better theory if we pursue both of them. The thesis is centered around the…
Supporting shared hypothesis testing in the biomedical domain.
Agibetov, Asan; Jiménez-Ruiz, Ernesto; Ondrésik, Marta; Solimando, Alessandro; Banerjee, Imon; Guerrini, Giovanna; Catalano, Chiara E; Oliveira, Joaquim M; Patanè, Giuseppe; Reis, Rui L; Spagnuolo, Michela
2018-02-08
Pathogenesis of inflammatory diseases can be tracked by studying the causality relationships among the factors contributing to its development. We could, for instance, hypothesize on the connections of the pathogenesis outcomes to the observed conditions. And to prove such causal hypotheses we would need to have the full understanding of the causal relationships, and we would have to provide all the necessary evidences to support our claims. In practice, however, we might not possess all the background knowledge on the causality relationships, and we might be unable to collect all the evidence to prove our hypotheses. In this work we propose a methodology for the translation of biological knowledge on causality relationships of biological processes and their effects on conditions to a computational framework for hypothesis testing. The methodology consists of two main points: hypothesis graph construction from the formalization of the background knowledge on causality relationships, and confidence measurement in a causality hypothesis as a normalized weighted path computation in the hypothesis graph. In this framework, we can simulate collection of evidences and assess confidence in a causality hypothesis by measuring it proportionally to the amount of available knowledge and collected evidences. We evaluate our methodology on a hypothesis graph that represents both contributing factors which may cause cartilage degradation and the factors which might be caused by the cartilage degradation during osteoarthritis. Hypothesis graph construction has proven to be robust to the addition of potentially contradictory information on the simultaneously positive and negative effects. The obtained confidence measures for the specific causality hypotheses have been validated by our domain experts, and, correspond closely to their subjective assessments of confidences in investigated hypotheses. Overall, our methodology for a shared hypothesis testing framework exhibits important properties that researchers will find useful in literature review for their experimental studies, planning and prioritizing evidence collection acquisition procedures, and testing their hypotheses with different depths of knowledge on causal dependencies of biological processes and their effects on the observed conditions.
Balasubramaniam, Krishna N; Beisner, Brianne A; Berman, Carol M; De Marco, Arianna; Duboscq, Julie; Koirala, Sabina; Majolo, Bonaventura; MacIntosh, Andrew J; McFarland, Richard; Molesti, Sandra; Ogawa, Hideshi; Petit, Odile; Schino, Gabriele; Sosa, Sebastian; Sueur, Cédric; Thierry, Bernard; de Waal, Frans B M; McCowan, Brenda
2018-01-01
Among nonhuman primates, the evolutionary underpinnings of variation in social structure remain debated, with both ancestral relationships and adaptation to current conditions hypothesized to play determining roles. Here we assess whether interspecific variation in higher-order aspects of female macaque (genus: Macaca) dominance and grooming social structure show phylogenetic signals, that is, greater similarity among more closely-related species. We use a social network approach to describe higher-order characteristics of social structure, based on both direct interactions and secondary pathways that connect group members. We also ask whether network traits covary with each other, with species-typical social style grades, and/or with sociodemographic characteristics, specifically group size, sex-ratio, and current living condition (captive vs. free-living). We assembled 34-38 datasets of female-female dyadic aggression and allogrooming among captive and free-living macaques representing 10 species. We calculated dominance (transitivity, certainty), and grooming (centrality coefficient, Newman's modularity, clustering coefficient) network traits as aspects of social structure. Computations of K statistics and randomization tests on multiple phylogenies revealed moderate-strong phylogenetic signals in dominance traits, but moderate-weak signals in grooming traits. GLMMs showed that grooming traits did not covary with dominance traits and/or social style grade. Rather, modularity and clustering coefficient, but not centrality coefficient, were strongly predicted by group size and current living condition. Specifically, larger groups showed more modular networks with sparsely-connected clusters than smaller groups. Further, this effect was independent of variation in living condition, and/or sampling effort. In summary, our results reveal that female dominance networks were more phylogenetically conserved across macaque species than grooming networks, which were more labile to sociodemographic factors. Such findings narrow down the processes that influence interspecific variation in two core aspects of macaque social structure. Future directions should include using phylogeographic approaches, and addressing challenges in examining the effects of socioecological factors on primate social structure. © 2017 Wiley Periodicals, Inc.
Vahip, Simavi; Kesebir, Sermin; Alkan, Müge; Yazici, Olcay; Akiskal, Knarig K; Akiskal, Hagop S
2005-03-01
This is a first attempt to evaluate the reliability and factor structure replicability of the Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire (TEMPS-A) in its Turkish Version. The questionnaire is a self-report 110-item measure that postulates five affective temperaments-the depressive, cyclothymic, irritable, hyperthymic, and anxious-which embody both strengths and liabilities along affective lines. The questionnaire was administered to 658 clinically-well subjects in a Turkish university circle. We undertook item analysis and test-retest reliability. We then examined internal consistency through factor analysis with PCA rotation. We found good to excellent test-retest reliability (0.73-0.91), and internal consistency (0.77-0.85). We deleted 10 items with factor loading <0.20 for their own subscales, resulting in a questionnaire with 99 items. Despite considerable overlap between depressive and cognitive anxiety traits, a distinct "nervous"-anxious factor emerged as well, and the hypothesized (original English) 5-factor structure of the TEMPS-A was supported. Cut-offs for each temperament were based on z-scores higher than +2S.D. Dominant irritable (3.7%), nervous-anxious (3.7%) and depressive (3.1%) temperaments were the most common in this population, whereas dominant cyclothymic (1.7%) and hyperthymic (1.2%) temperaments were relatively uncommon. These temperaments tended to lose their intensity with age. As expected, women scored significantly higher on the nervous-anxious, and men on the hyperthymic temperaments. The sample was composed of younger subjects with higher education than the general population of Turkey. Although the distribution of the scores for each of the temperaments deviated somewhat from normal curves, for heuristic reasons we did attempt to provide prevalence rates based on z-scores. In this preliminary version of the TEMPS-A, we have retained 100 (of the original 110) traits loading >0.20. Some deleted items referred to sleep, others appeared socially desirability traits in the Turkish culture endorsed by many subjects. Nonetheless, item analyses within each factor revealed traits indicative of personal assets (specific to each temperament) along with those which might represent vulnerability to affective illness. This is in line with the hypothesized original theoretical framework of the senior authors. Even in this "first pass," in its Turkish version the TEMPS-A is a reliable and valid instrument. Further refinement of the instrument will require the study of a nationally representative sample in Turkey.
Buist-Bouwman, M A; Ormel, J; De Graaf, R; Vilagut, G; Alonso, J; Van Sonderen, E; Vollebergh, W A M
2008-01-01
This study assessed the factor structure, internal consistency, and discriminatory validity of the World Health Organization Disability Assessment Schedule (WHODAS) version used in the European Study of the Epidemiology of Mental Disorders (ESEMeD). In total 8796 adults were assessed using the ESEMeD WHODAS (22 severity and 8 frequency items). An Exploratory Factor Analysis (EFA) with promax rotation was done with a random 50%. The other half was used for confirmatory factor analysis (CFA) comparing models (a) suggested by EFA; (b) hypothesized a priori; and (c) reduced with four items. A CFA model with covariates was conducted in the whole sample to assess invariance across Mediterranean (Spain, France and Italy) and non-Mediterranean (Belgium, Germany and the Netherlands) countries. Cronbach's alphas and discriminatory validity were also examined. EFA identified seven factors (explained variance: 80%). The reduced model (six factors, four frequency items excluded) presented the best fit [Confirmatory Fit Index (CFI) = 0.992, Tucker-Lewis Index (TLI) = 0.996, Root Mean Square Error of Approximation (RMSEA) = 0.024]. The second-order factor structure also fitted well (CFI = 0.987, TLI = 0.991, RMSEA = 0.036). Measurement non-invariance was found for Embarrassment. Cronbach's alphas ranged from 0.84 for Participation to 0.93 for Mobility. Preliminary data suggest acceptable discriminatory validity. Thus, the ESEMeD WHODAS may well be a valuable shortened version of the WHODAS-II, but future users should reconsider the filter questions. Copyright (c) 2008 John Wiley & Sons, Ltd.
A measurement model for general noise reaction in response to aircraft noise.
Kroesen, Maarten; Schreckenberg, Dirk
2011-01-01
In this paper a measurement model for general noise reaction (GNR) in response to aircraft noise is developed to assess the performance of aircraft noise annoyance and a direct measure of general reaction as indicators of this concept. For this purpose GNR is conceptualized as a superordinate latent construct underlying particular manifestations. This conceptualization is empirically tested through estimation of a second-order factor model. Data from a community survey at Frankfurt Airport are used for this purpose (N=2206). The data fit the hypothesized factor structure well and support the conceptualization of GNR as a superordinate construct. It is concluded that noise annoyance and a direct measure of general reaction to noise capture a large part of the negative feelings and emotions in response to aircraft noise but are unable to capture all relevant variance. The paper concludes with recommendations for the valid measurement of community reaction and several directions for further research.
Klemanski, David H; Curtiss, Joshua; McLaughlin, Katie A; Nolen-Hoeksema, Susan
2017-04-01
Social anxiety and depression are common mental health problems among adolescents and are frequently comorbid. Primary aims of this study were to (1) elucidate the nature of individual differences in specific emotion regulation deficits among adolescents with symptoms of social anxiety and depression, and (2) determine whether repetitive negative thinking (RNT) functions as a transdiagnostic factor. A diverse sample of adolescents (N = 1065) completed measures assessing emotion regulation and symptoms of social anxiety and depression. Results indicated that adolescents with high levels of social anxiety and depression symptoms reported decreased emotional awareness, dysregulated emotion expression, and reduced use of emotion management strategies. The hypothesized structural model in which RNT functions as a transdiagnostic factor exhibited a better fit than an alternative model in which worry and rumination function as separate predictors of symptomatology. Findings implicate emotion regulation deficits and RNT in the developmental psychopathology of youth anxiety and mood disorders.
Martin, Andrew J
2008-02-01
The present study assessed the application of a multidimensional model of motivation and engagement (the Motivation and Engagement Wheel) and its accompanying instrumentation (the Motivation and Engagement Scale) to the music and sport domains. Participants were 463 young classical musicians (N=224) and sportspeople (N=239). In both music and sport samples, the data confirmed the good fit of the four hypothesized higher-order dimensions and their 11 first-order dimensions: adaptive cognitions (self-efficacy, valuing, mastery orientation), adaptive behaviors (planning, task management, persistence), impeding/maladaptive cognitions (uncertain control, anxiety, failure avoidance), and maladaptive behaviors (self-handicapping, disengagement). Multigroup tests of factor invariance showed that in terms of underlying motivational constructs and the composition of and relationships among these constructs, key subsamples are not substantially different. Moreover-and of particular relevance to issues around the generalizability of the framework-the factor structure for music and sport samples was predominantly invariant.
McKay, Michael T; Morgan, Grant B; van Exel, N Job; Worrell, Frank C
2015-01-01
Despite its widespread use, disagreement remains regarding the structure of the Consideration of Future Consequences Scale (CFCS). In particular there is disagreement regarding whether the scale assesses future orientation as a unidimensional or multidimensional (immediate and future) construct. Using 2 samples of high school students in the United Kingdom, 4 models were tested. The totality of results including item loadings, goodness-of-fit indexes, and reliability estimates all supported the bifactor model, suggesting that the 2 hypothesized factors are better understood as grouping or method factors rather than as representative of latent constructs. Accordingly this study supports the unidimensionality of the CFCS and the scoring of all 12 items to produce a global future orientation score. Researchers intending to use the CFCS, and those with existing data, are encouraged to examine a bifactor solution for the scale.
Assessment of the psychometric properties of the Family Management Measure.
Knafl, Kathleen; Deatrick, Janet A; Gallo, Agatha; Dixon, Jane; Grey, Margaret; Knafl, George; O'Malley, Jean
2011-06-01
This paper reports development of the Family Management Measure (FaMM) of parental perceptions of family management of chronic conditions. By telephone interview, 579 parents of children age 3 to 19 with a chronic condition (349 partnered mothers, 165 partners, 65 single mothers) completed the FaMM and measures of child functional status and behavioral problems and family functioning. Analyses addressed reliability, factor structure, and construct validity. Exploratory factor analysis yielded six scales: Child's Daily Life, Condition Management Ability, Condition Management Effort, Family Life Difficulty, Parental Mutuality, and View of Condition Impact. Internal consistency reliability ranged from .72 to .91, and test-retest reliability from .71 to .94. Construct validity was supported by significant correlations in hypothesized directions between FaMM scales and established measures. Results support FaMM's; reliability and validity, indicating it performs in a theoretically meaningful way and taps distinct aspects of family response to childhood chronic conditions.
Safety management in a relationship-oriented culture.
Hsu, Shang Hwa; Lee, Chun-Chia
2012-01-01
A relationship-oriented culture predominates in the Greater China region, where it is more important than in Western countries. Some characteristics of this culture influence strongly the organizational structure and interactions among members in an organization. This study aimed to explore the possible influence of relationships on safety management in relationship-oriented cultures. We hypothesized that organizational factors (management involvement and harmonious relationships) within a relationship-oriented culture would influence supervisory work (ongoing monitoring and task instructions), the reporting system (selective reporting), and teamwork (team communication and co-ordination) in safety management at a group level, which would in turn influence individual reliance complacency, risk awareness, and practices. We distributed a safety climate questionnaire to the employees of Taiwanese high-risk industries. The results of structural equation modeling supported the hypothesis. This article also discusses the findings and implications for safety improvement in countries with a relationship-oriented culture.
NASA Astrophysics Data System (ADS)
Barlocco, Daniela; Cignarella, Giorgio; Greco, Giovanni; Novellino, Ettore
1993-10-01
Molecular modeling studies were carried out on a set of piperazine and 3,8-diazabicyclo[3.2.1]octane derivatives with the aim to highlight the main factors modulating their affinity for the μ-opioid receptor. Structure-affinity relationships were developed with the aid of molecular mechanics and semiempirical quantum-mechanics methods. According to our proposed pharmacodynamic model, the binding to the μ-receptor is promoted by the following physico-chemical features: the presence of hydrocarbon fragments on the nitrogen ring frame capable of interacting with one of two hypothesized hydrophobic receptor pockets; a `correct' orientation of an N-propionyl side chain so as to avoid a sterically hindered region of the receptor; the possibility of accepting a hydrogen bond from a receptor site complementary to the morphine phenol oxygen.
The Impact of Schools on Learning: Inner-City Children in Suburban Schools
ERIC Educational Resources Information Center
Mahan, Thomas W.; Mahan, Aline M.
1971-01-01
Hypotheses tested were that the average achievement level of the classroom is a determining factor in achievement of urban minority group children and that social acceptance of the urban minority child by white middle class peers is related to academic achievement. Results using urban and suburban schools supported the hypotheses. (Author/CG)
The Role of Episodic Structure and of Story Length in Children's Recall of Simple Stories
ERIC Educational Resources Information Center
Glenn, Christine G.
1978-01-01
It was hypothesized that if the episodic structure of a story determines subjects' organization of that story in memory, then variation in structure should affect the organization of information in recall. (Author/NCR)
A terrestrial lidar assessment of climate change impacts on forest structure
NASA Astrophysics Data System (ADS)
van Aardt, J. A.; Kelbe, D.; Sacca, K.; Giardina, C. P.; Selmants, P. C.; Litton, C. M.; Asner, G. P.
2016-12-01
The projected impact of climate change on ecosystems has received much scientific attention, specifically related to geographical species shifts and carbon allocation. This study, however, was undertaken to assess the expected changes in tropical forest structure as a function of changing temperatures. Our study area is a constrained model ecological system and is located on the eastern flank of Mauna Kea Volcano, Hawaii, USA. Nine plots from this closed-canopy, tropical montane wet forest fall along an elevation-based 5.2°C mean annual temperature (MAT) gradient, where multiple other biotic and abiotic factors are held nearly constant. This MAT gradient has been used to assess subtle temperature effects on ecosystem functioning including carbon cycles, but less has been done on the effects of temperature on vegetation structure. We acquired vegetation structural data using a SICK-LMS151 terrestrial laser scanner (905 nm) for full 270x360° coverage. This Compact Biomass Lidar (CBL) was developed by Rochester Institute of Technology and the University of Massachusetts, Boston. Data for each plot along the temperature gradient were collected in a 20 m x 20 m configuration at a 5 m scan spacing. Initial challenges, related to the irregular radial scan pattern and registration of 25 scans per plot, were addressed in order to extract normalized vegetation density metrics and to mitigate occlusion effects, respectively. However, we believe that the CBL scans can be assessed independently, i.e., treating 25 scans/plot as a population sample. We derived height statistics, return density metrics, canopy rugosity, and higher-order metrics in order to describe the differences in vegetation structure, which ultimately will be tied to the elevation-induced temperature range. We hypothesized that, for this MAT gradient (i) vertical vegetation stratification; (ii) diameter distributions; and (iii) aboveground biomass will differ significantly, while more species-dependent canopy rugosity remain stable. Our results support these hypotheses, allowing for future studies of vegetation structural responses to static and dynamic climate drivers. The findings have implications for forest management, mitigation strategies to limit losses in carbon sequestration, and forest inventory in structurally complex forests.
Harrop, Tiffany M; Preston, Olivia C; Khazem, Lauren R; Anestis, Michael D; Junearick, Regis; Green, Bradley A; Anestis, Joye C
2017-10-01
Studies have identified independent relationships between psychopathy, narcissism, and suicidality. The current study expands upon the extant literature by exploring psychopathic and narcissistic personality traits and components of the interpersonal-psychological theory of suicide, utilizing a 3-factor model of psychopathy and 2-factor model of pathological narcissism in community, undergraduate, and military individuals. We hypothesized that the impulsive-antisocial facets of psychopathy would be related to suicidal desire, whereas all facets of psychopathy would relate to the capability for suicide. We anticipated an association between pathological narcissism, thwarted belongingness, and capability for suicide, but not perceived burdensomeness. We further hypothesized a relationship between physical pain tolerance and persistence and the affective (i.e., callousness) facet of psychopathy. Results partially supported these hypotheses and underscore the need for further examination of these associations utilizing contemporary models of psychopathy and narcissism. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Davis, Laurel; Hanson, Sheila K; Zamir, Osnat; Gewirtz, Abigail H; DeGarmo, David S
2015-08-01
Deployment separation and reunifications are salient contexts that directly impact effective family functioning and parenting for military fathers. Yet, we know very little about determinants of postdeployed father involvement and effective parenting. The present study examined hypothesized risk and protective factors of observed parenting for 282 postdeployed fathers who served in the National Guard/Reserves. Preintervention data were employed from fathers participating in the After Deployment, Adaptive Parenting Tools randomized control trial. Parenting practices were obtained from direct observation of father-child interaction and included measures of problem solving, harsh discipline, positive involvement, encouragement, and monitoring. Risk factors included combat exposure, negative life events, months deployed, and posttraumatic stress disorder symptoms. Protective factors included education, income, dyadic adjustment, and social support. Results of a structural equation model assessing risk and protective factors for an effective parenting construct indicated that months deployed, income, and father age were most related to observed parenting, explaining 16% of the variance. We are aware of no other study using direct parent-child observations of fathers' parenting skills following overseas deployment. Implications for practice and preventive intervention are discussed. (c) 2015 APA, all rights reserved).
Cohen, Lisa Janet; Gorman, Bernard; Briggs, Jessica; Jeon, Min Eun; Ginsburg, Tal; Galynker, Igor
2018-02-04
In this study, we introduce the construct of the suicidal narrative, a hypothetical personal narrative linked to imminent suicide, and explore its relationship to near-term suicidal risk and the suicide crisis syndrome (SCS). Psychiatric outpatients (N = 289) were administered the Columbia Suicide-Severity Rating Scale (C-SSRS), Suicide Crisis Inventory (SCI), and Suicide Narrative Inventory (SNI), a novel instrument combining the documented risk factors of Thwarted Belongingness, Perceived Burdensomeness, Humiliation, Social Defeat, Goal Disengagement, and Goal Reengagement. Dimensional measures of past month, lifetime, and past suicidal phenomena, incorporating ideation and behavior, were calculated from the C-SSRS. Structural equation modeling was used to explore the interaction among variables. Factor analysis of the SNI yielded two orthogonal factors, termed Interpersonal and Goal Orientation. The former factor was comprised of Perceived Burdensomeness, Social Defeat, Humiliation, and Thwarted Belongingness, the latter of Goal Disengagement and Goal Reengagement. The Interpersonal factor correlated with both SCS severity and suicidal phenomena in each time frame and the Goal Orientation factor with no other variable. As hypothesized, the proposed model was significant for the past month only. Our findings support the construct of the suicidal narrative and its function as a near-term suicidal risk factor. © 2018 The American Association of Suicidology.
Alienation and the Ontology of Social Structure.
ERIC Educational Resources Information Center
Segalman, Ralph
Theoretical models of social structure are analyzed in light of modern work patterns, social affiliations, and social attitudes. It is hypothesized that previous paradigms for society were based on classic theory which analyzed the then emergent forms of social structure and relationships. Because social structures and relationships have changed,…
ERIC Educational Resources Information Center
Guisasola, Jenaro; Ceberio, Mikel; Zubimendi, Jose Luis
2006-01-01
The study we present tries to explore how first year engineering students formulate hypotheses in order to construct their own problem solving structure when confronted with problems in physics. Under the constructivistic perspective of the teaching-learning process, the formulation of hypotheses plays a key role in contrasting the coherence of…
ERIC Educational Resources Information Center
Wu, Amery D.; Stone, Jake E.
2016-01-01
This article explores an approach for test score validation that examines test takers' strategies for taking a reading comprehension test. The authors formulated three working hypotheses about score validity pertaining to three types of test-taking strategy (comprehending meaning, test management, and test-wiseness). These hypotheses were…
Social imagery, tobacco independence, and the truthsm campaign.
Evans, W Douglas; Price, Simani; Blahut, Steven; Hersey, James; Niederdeppe, Jeffrey; Ray, Sarah
2004-01-01
This study investigated relationships among exposure to the truthsm campaign, differences in social imagery about not smoking and related measures, and smoking behavior. We asked, "How does truthsm work? Through what psychological mechanisms does it affect smoking behavior?" We developed a framework to explain how receptivity to truthsm ads might influence youth cognitive states and subsequent effects on progression to established smoking. The main hypotheses were that social imagery about not smoking and related beliefs and attitudes about tobacco use mediate the relationship between truthsm exposure and smoking status. The study was based on data from the Legacy Media Tracking Survey (LMTS), waves I-III, which were conducted at three time points from 1999 through 2001. A nationally representative sample of 20,058 respondents aged 12-24 from the three time points was used in the analysis. We developed a structural equation model (SEM) based on constructs drawn from the LMTS. We investigated the model and tested our hypotheses about the psychological and behavioral effects of campaign exposure. We tested our constructs and model using a two-stage structural equation modeling approach. We first conducted a confirmatory factor analysis (CFA) to test the measurement model. Our model achieved satisfactory fit, and we conducted the SEM to test our hypotheses. We found that social imagery and perceived tobacco independence mediate the relationship between truthsm exposure and smoking status. We found meaningful differences between paths for segmented samples based on age, gender, and race/ethnicity subgroups and over time. The truthsm campaign operates through individuals'sense of tobacco independence and social imagery about not smoking. This study indicates that the campaign's strategy has worked as predicted and represents an effective model for social marketing to change youth risk behaviors. Future studies should further investigate subgroup differences in campaign reactions and utilize contextual information about the truthsm campaign's evolution to explain changes in reactions over time.
Histopathologic study of human vocal fold mucosa unphonated over a decade.
Sato, Kiminori; Umeno, Hirohito; Ono, Takeharu; Nakashima, Tadashi
2011-12-01
Mechanotransduction caused by vocal fold vibration could possibly be an important factor in the maintenance of extracellular matrices and layered structure of the human adult vocal fold mucosa as a vibrating tissue after the layered structure has been completed. Vocal fold stellate cells (VFSCs) in the human maculae flavae of the vocal fold mucosa are inferred to be involved in the metabolism of extracellular matrices of the vocal fold mucosa. Maculae flavae are also considered to be an important structure in the growth and development of the human vocal fold mucosa. Tension caused by phonation (vocal fold vibration) is hypothesized to stimulate the VFSCs to accelerate production of extracellular matrices. A human adult vocal fold mucosa unphonated over a decade was investigated histopathologically. Vocal fold mucosa unphonated for 11 years and 2 months of a 64-year-old male with cerebral hemorrhage was investigated by light and electron microscopy. The vocal fold mucosae (including maculae flavae) were atrophic. The vocal fold mucosa did not have a vocal ligament, Reinke's space or a layered structure. The lamina propria appeared as a uniform structure. Morphologically, the VFSCs synthesized fewer extracellular matrices, such as fibrous protein and glycosaminoglycan. Consequently, VFSCs appeared to decrease their level of activity.
Alderwick, Luke J.; Molle, Virginie; Kremer, Laurent; Cozzone, Alain J.; Dafforn, Timothy R.; Besra, Gurdyal S.; Fütterer, Klaus
2006-01-01
Ser/Thr phosphorylation has emerged as a critical regulatory mechanism in a number of bacteria, including Mycobacterium tuberculosis. This problematic pathogen encodes 11 eukaryotic-like Ser/Thr kinases, yet few substrates or signaling targets have been characterized. Here, we report the structure of EmbR (2.0 Å), a putative transcriptional regulator of key arabinosyltransferases (EmbC, -A, and -B), and an endogenous substrate of the Ser/Thr-kinase PknH. EmbR presents a unique domain architecture: the N-terminal winged-helix DNA-binding domain forms an extensive interface with the all-helical central bacterial transcriptional activation domain and is positioned adjacent to the regulatory C-terminal forkhead-associated (FHA) domain, which mediates binding to a Thr-phosphorylated site in PknH. The structure in complex with a phospho-peptide (1.9 Å) reveals a conserved mode of phospho-threonine recognition by the FHA domain and evidence for specific recognition of the cognate kinase. The present structures suggest hypotheses as to how EmbR might propagate the phospho-relay signal from its cognate kinase, while serving as a template for the structurally uncharacterized Streptomyces antibiotic regulatory protein family of transcription factors. PMID:16477027
Chimaeric sounds reveal dichotomies in auditory perception
Smith, Zachary M.; Delgutte, Bertrand; Oxenham, Andrew J.
2008-01-01
By Fourier's theorem1, signals can be decomposed into a sum of sinusoids of different frequencies. This is especially relevant for hearing, because the inner ear performs a form of mechanical Fourier transform by mapping frequencies along the length of the cochlear partition. An alternative signal decomposition, originated by Hilbert2, is to factor a signal into the product of a slowly varying envelope and a rapidly varying fine time structure. Neurons in the auditory brainstem3–6 sensitive to these features have been found in mammalian physiological studies. To investigate the relative perceptual importance of envelope and fine structure, we synthesized stimuli that we call ‘auditory chimaeras’, which have the envelope of one sound and the fine structure of another. Here we show that the envelope is most important for speech reception, and the fine structure is most important for pitch perception and sound localization. When the two features are in conflict, the sound of speech is heard at a location determined by the fine structure, but the words are identified according to the envelope. This finding reveals a possible acoustic basis for the hypothesized ‘what’ and ‘where’ pathways in the auditory cortex7–10. PMID:11882898
Dwyer, John M; Fensham, Rod J; Buckley, Yvonne M
2010-10-01
Opportunities for dual restoration and carbon benefits from naturally regenerating woody ecosystems in agricultural landscapes have been highlighted recently. The restoration capacity of woody ecosystems depends on the magnitude and duration of ecosystem modification, i.e., the "agricultural legacy." However, this legacy may not influence carbon sequestration in the same way as restoration because carbon potential depends primarily on biomass accumulation, with little consideration of other attributes and functions of the ecosystem. Our present study simultaneously assesses the restoration and carbon potential of Acacia harpophylla regrowth, an extensive regrowth ecosystem in northeastern Australia. We used a landscape-scale survey of A. harpophylla regrowth to test the following hypotheses: (1) management history, in combination with climatic and edaphic factors, has long-term effects on stem densities, and (2) higher-density stands have lower restoration and carbon potential, which is also influenced by climatic and edaphic factors. We focused on the restoration of forest structure, which was characterized using stem density, aboveground biomass, stem heights, and stem diameters. Data were analyzed using multilevel models within the hierarchical Bayesian model (HBM) framework. We found strong support for both hypotheses. Repeated attempts at clearing Brigalow (A. harpophylla ecosystem) regrowth increases stem densities, and these densities remain high over the long term, particularly in high-rainfall areas and on gilgaied, high-clay soils (hypothesis 1). In models testing hypothesis 2, interactions between stem density and stand age indicate that higher-density stands have slower biomass accumulation and structural development in the long term. After accounting for stem density and stand age, annual rainfall had a positive effect on biomass accumulation and structural development. Other climate and soil variables were retained in the various models but had weaker effects. Spatial extrapolations of the HBMs indicated that the central and eastern parts of the study region are most suitable for biomass accumulation; however, these may not correspond to the areas that historically supported the highest biomass Brigalow forests. We conclude that carbon and restoration goals are largely congruent within areas of similar climate. At the regional scale, however, spatial prioritization of restoration and carbon projects may only be aligned where carbon benefits will be high.
Lesnik-Oberstein, M; Koers, A J; Cohen, L
1995-01-01
A revised version of the three-factor theory of child abuse (Lesnik-Oberstein, Cohen, & Koers, 1982) is presented. Further, we report on a research designed to test three main hypotheses derived from Factor I (1) (a high level of hostility in abusive parents) and its sources. The three main hypotheses are: (1) that psychologically abusive mothers have a high level of hostile feelings (Factor I); (2) that the high level of hostile feelings in abusive mothers is associated with low marital coping skills (resulting in affectionless, violent marriages), a negative childhood upbringing (punitive, uncaring, over controlling), a high level of stress (objective stress), and a high level of strain (low self-esteem, depression, neurotic symptoms, social anxiety, feelings of being wronged); and (3) that maternal psychological child abuse is associated with low marital coping skills, a negative childhood upbringing, a high level of stress and a high level of strain. Forty-four psychologically abusing mothers were compared with 128 nonabusing mothers on a variety of measures and were matched for age and educational level. All the mothers had children who were hospitalized for medical symptoms. The three hypotheses were supported, with the exception of the component of hypothesis 2 concerning the association between objective stress and maternal hostility. The positive results are consistent with the three-factor theory.
Progress in violence risk assessment and communication: hypothesis versus evidence.
Harris, Grant T; Rice, Marnie E
2015-02-01
We draw a distinction between hypothesis and evidence with respect to the assessment and communication of the risk of violent recidivism. We suggest that some authorities in the field have proposed quite valid and reasonable hypotheses with respect to several issues. Among these are the following: that accuracy will be improved by the adjustment or moderation of numerical scores based on clinical opinions about rare risk factors or other considerations pertaining to the applicability to the case at hand; that there is something fundamentally distinct about protective factors so that they are not merely the obverse of risk factors, such that optimal accuracy cannot be achieved without consideration of such protective factors; and that assessment of dynamic factors is required for optimal accuracy and furthermore interventions aimed at such dynamic factors can be expected to cause reductions in violence risk. We suggest here that, while these are generally reasonable hypotheses, they have been inappropriately presented to practitioners as empirically supported facts, and that practitioners' assessment and communication about violence risk run beyond that supported by the available evidence as a result. We further suggest that this represents harm, especially in impeding scientific progress. Nothing here justifies stasis or simply surrendering to authoritarian custody with somatic treatment. Theoretically motivated and clearly articulated assessment and intervention should be provided for offenders, but in a manner that moves the field more firmly from hypotheses to evidence. Copyright © 2015 John Wiley & Sons, Ltd.
Organisation of biotechnological information into knowledge.
Boh, B
1996-09-01
The success of biotechnological research, development and marketing depends to a large extent on the international transfer of information and on the ability to organise biotechnology information into knowledge. To increase the efficiency of information-based approaches, an information strategy has been developed and consists of the following stages: definition of the problem, its structure and sub-problems; acquisition of data by targeted processing of computer-supported bibliographic, numeric, textual and graphic databases; analysis of data and building of specialized in-house information systems; information processing for structuring data into systems, recognition of trends and patterns of knowledge, particularly by information synthesis using the concept of information density; design of research hypotheses; testing hypotheses in the laboratory and/or pilot plant; repeated evaluation and optimization of hypotheses by information methods and testing them by further laboratory work. The information approaches are illustrated by examples from the university-industry joint projects in biotechnology, biochemistry and agriculture.
Structural equation modeling: building and evaluating causal models: Chapter 8
Grace, James B.; Scheiner, Samuel M.; Schoolmaster, Donald R.
2015-01-01
Scientists frequently wish to study hypotheses about causal relationships, rather than just statistical associations. This chapter addresses the question of how scientists might approach this ambitious task. Here we describe structural equation modeling (SEM), a general modeling framework for the study of causal hypotheses. Our goals are to (a) concisely describe the methodology, (b) illustrate its utility for investigating ecological systems, and (c) provide guidance for its application. Throughout our presentation, we rely on a study of the effects of human activities on wetland ecosystems to make our description of methodology more tangible. We begin by presenting the fundamental principles of SEM, including both its distinguishing characteristics and the requirements for modeling hypotheses about causal networks. We then illustrate SEM procedures and offer guidelines for conducting SEM analyses. Our focus in this presentation is on basic modeling objectives and core techniques. Pointers to additional modeling options are also given.
Factors that encourage females to pursue physical science careers: Testing five common hypotheses
NASA Astrophysics Data System (ADS)
Hazari, Zahra; Potvin, Geoff; Lock, Robynne M.; Lung, Florin; Sadler, Philip M.; Sonnert, Gerhard
2012-03-01
There are many hypotheses regarding factors that may encourage female students to pursue careers in the physical sciences. Using Propensity Score Matching (PSM) on national data (n=7505) drawn from the Persistence Research in Science and Engineering (PRiSE) project, we test five commonly held beliefs including having a single-sex physics class, having a female physics teacher, having female scientist guest speakers in physics class, discussing the work of women scientists in physics class, and discussing the under-representation of women in physics class. The effect of these experiences is compared for female students who are matched on several factors, including parental education, prior science/math interests, and academic background, thereby controlling for the effect of many confounding variables.
Do multiple fires interact to affect vegetation structure in temperate eucalypt forests?
Haslem, Angie; Leonard, Steve W J; Bruce, Matthew J; Christie, Fiona; Holland, Greg J; Kelly, Luke T; MacHunter, Josephine; Bennett, Andrew F; Clarke, Michael F; York, Alan
2016-12-01
Fire plays an important role in structuring vegetation in fire-prone regions worldwide. Progress has been made towards documenting the effects of individual fire events and fire regimes on vegetation structure; less is known of how different fire history attributes (e.g., time since fire, fire frequency) interact to affect vegetation. Using the temperate eucalypt foothill forests of southeastern Australia as a case study system, we examine two hypotheses about such interactions: (1) post-fire vegetation succession (e.g., time-since-fire effects) is influenced by other fire regime attributes and (2) the severity of the most recent fire overrides the effect of preceding fires on vegetation structure. Empirical data on vegetation structure were collected from 540 sites distributed across central and eastern Victoria, Australia. Linear mixed models were used to examine these hypotheses and determine the relative influence of fire and environmental attributes on vegetation structure. Fire history measures, particularly time since fire, affected several vegetation attributes including ground and canopy strata; others such as low and sub-canopy vegetation were more strongly influenced by environmental characteristics like rainfall. There was little support for the hypothesis that post-fire succession is influenced by fire history attributes other than time since fire; only canopy regeneration was influenced by another variable (fire type, representing severity). Our capacity to detect an overriding effect of the severity of the most recent fire was limited by a consistently weak effect of preceding fires on vegetation structure. Overall, results suggest the primary way that fire affects vegetation structure in foothill forests is via attributes of the most recent fire, both its severity and time since its occurrence; other attributes of fire regimes (e.g., fire interval, frequency) have less influence. The strong effect of environmental drivers, such as rainfall and topography, on many structural features show that foothill forest vegetation is also influenced by factors outside human control. While fire is amenable to human management, results suggest that at broad scales, structural attributes of these forests are relatively resilient to the effects of current fire regimes. Nonetheless, the potential for more frequent severe fires at short intervals, associated with a changing climate and/or fire management, warrant further consideration. © 2016 by the Ecological Society of America.
Meinck, Franziska; Boyes, Mark E; Cluver, Lucie; Ward, Catherine L; Schmidt, Peter; DeStone, Sachin; Dunne, Michael P
2018-05-31
Child abuse prevention research has been hampered by a lack of validated multi-dimensional non-proprietary instruments, sensitive enough to measure change in abuse victimization or behavior. This study aimed to adapt the ICAST child abuse self-report measure (parent and child) for use in intervention studies and to investigate the psychometric properties of this substantially modified tool in a South African sample. First, cross-cultural and sensitivity adaptation of the original ICAST tools resulted in two preliminary measures (ICAST-Trial adolescents: 27 items, ICAST-Trial caregivers: 19 items). Second, ICAST-Trial data from a cluster randomized trial of a parenting intervention for families with adolescents (N = 1104, 552 caregiver-adolescent dyads) was analyzed. Confirmatory factor analysis established the hypothesized 6-factor (adolescents) and 4-factor (caregivers) structure. Removal of two items for adolescents and five for caregivers resulted in adequate model fit. Concurrent criterion validity analysis confirmed hypothesized relationships between child abuse and adolescent and caregiver mental health, adolescent behavior, discipline techniques and caregiver childhood abuse history. The resulting ICAST-Trial measures have 25 (adolescent) and 14 (caregiver) items respectively and measure physical, emotional and contact sexual abuse, neglect (both versions), and witnessing intimate partner violence and sexual harassment (adolescent version). The study established that both tools are sensitive to measuring change over time in response to a parenting intervention. The ICAST-Trial should have utility for evaluating the effectiveness of child abuse prevention efforts in similar socioeconomic contexts. Further research is needed to replicate these findings and examine cultural appropriateness, barriers for disclosure, and willingness to engage in child abuse research. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
An approach to large scale identification of non-obvious structural similarities between proteins
Cherkasov, Artem; Jones, Steven JM
2004-01-01
Background A new sequence independent bioinformatics approach allowing genome-wide search for proteins with similar three dimensional structures has been developed. By utilizing the numerical output of the sequence threading it establishes putative non-obvious structural similarities between proteins. When applied to the testing set of proteins with known three dimensional structures the developed approach was able to recognize structurally similar proteins with high accuracy. Results The method has been developed to identify pathogenic proteins with low sequence identity and high structural similarity to host analogues. Such protein structure relationships would be hypothesized to arise through convergent evolution or through ancient horizontal gene transfer events, now undetectable using current sequence alignment techniques. The pathogen proteins, which could mimic or interfere with host activities, would represent candidate virulence factors. The developed approach utilizes the numerical outputs from the sequence-structure threading. It identifies the potential structural similarity between a pair of proteins by correlating the threading scores of the corresponding two primary sequences against the library of the standard folds. This approach allowed up to 64% sensitivity and 99.9% specificity in distinguishing protein pairs with high structural similarity. Conclusion Preliminary results obtained by comparison of the genomes of Homo sapiens and several strains of Chlamydia trachomatis have demonstrated the potential usefulness of the method in the identification of bacterial proteins with known or potential roles in virulence. PMID:15147578
Understanding the Anatomic Basis for Obstructive Sleep Apnea Syndrome in Adolescents
Kim, Christopher; Bagchi, Sheila; Keenan, Brendan T.; Comyn, François-Louis; Wang, Stephen; Tapia, Ignacio E.; Huang, Shirley; Traylor, Joel; Torigian, Drew A.; Bradford, Ruth M.; Marcus, Carole L.
2015-01-01
Rationale: Structural risk factors for obstructive sleep apnea syndrome (OSAS) in adolescents have not been well characterized. Because many adolescents with OSAS are obese, we hypothesized that the anatomic OSAS risk factors would be more similar to those in adults than those in children. Objectives: To investigate the anatomic risk factors in adolescents with OSAS compared with obese and lean control subjects using magnetic resonance imaging (MRI). Methods: Three groups of adolescents (age range: 12–16 yr) underwent MRI: obese individuals with OSAS (n = 49), obese control subjects (n = 38), and lean control subjects (n = 50). Measurements and Main Results: We studied 137 subjects and found that (1) obese adolescents with OSAS had increased adenotonsillar tissue compared with obese and lean control subjects; (2) obese OSAS adolescents had a smaller nasopharyngeal airway than control subjects; (3) the size of other upper airway soft tissue structures (volume of the tongue, parapharyngeal fat pads, lateral walls, and soft palate) was similar between subjects with OSAS and obese control subjects; (4) although there were no major craniofacial abnormalities in most of the adolescents with OSAS, the ratio of soft tissue to craniofacial space surrounding the airway was increased; and (5) there were sex differences in the pattern of lymphoid proliferation. Conclusions: Increased size of the pharyngeal lymphoid tissue, rather than enlargement of the upper airway soft tissue structures, is the primary anatomic risk factor for OSAS in obese adolescents. These results are important for clinical decision making and suggest that adenotonsillectomy should be considered as the initial treatment for OSAS in obese adolescents, a group that has poor continuous positive airway pressure adherence and difficulty in achieving weight loss. PMID:25835282
Environmental modeling and recognition for an autonomous land vehicle
NASA Technical Reports Server (NTRS)
Lawton, D. T.; Levitt, T. S.; Mcconnell, C. C.; Nelson, P. C.
1987-01-01
An architecture for object modeling and recognition for an autonomous land vehicle is presented. Examples of objects of interest include terrain features, fields, roads, horizon features, trees, etc. The architecture is organized around a set of data bases for generic object models and perceptual structures, temporary memory for the instantiation of object and relational hypotheses, and a long term memory for storing stable hypotheses that are affixed to the terrain representation. Multiple inference processes operate over these databases. Researchers describe these particular components: the perceptual structure database, the grouping processes that operate over this, schemas, and the long term terrain database. A processing example that matches predictions from the long term terrain model to imagery, extracts significant perceptual structures for consideration as potential landmarks, and extracts a relational structure to update the long term terrain database is given.
Keller, Robert T
2006-01-01
Transformational leadership, initiating structure, and selected substitutes for leadership were studied as longitudinal predictors of performance in 118 research and development (R&D) project teams from 5 firms. As hypothesized, transformational leadership predicted 1-year-later technical quality, schedule performance, and cost performance and 5-year-later profitability and speed to market. Initiating structure predicted all the performance measures. The substitutes of subordinate ability and an intrinsically satisfying task each predicted technical quality and profitability, and ability predicted speed to market. Moderator effects for type of R&D work were hypothesized and found whereby transformational leadership was a stronger predictor of technical quality in research projects, whereas initiating structure was a stronger predictor of technical quality in development projects. Implications for leadership theory and research are discussed. (c) 2006 APA, all rights reserved.
Association of West Nile virus illness and urban landscapes in Chicago and Detroit.
Ruiz, Marilyn O; Walker, Edward D; Foster, Erik S; Haramis, Linn D; Kitron, Uriel D
2007-03-12
West Nile virus infection in humans in urban areas of the Midwestern United States has exhibited strong spatial clustering during epidemic years. We derived urban landscape classes from the physical and socio-economic factors hypothesized to be associated with West Nile Virus (WNV) transmission and compared those to human cases of illness in 2002 in Chicago and Detroit. The objectives were to improve understanding of human exposure to virus-infected mosquitoes in the urban context, and to assess the degree to which environmental factors found to be important in Chicago were also found in Detroit. Five urban classes that partitioned the urban space were developed for each city region. The classes had many similarities in the two settings. In both regions, the WNV case rate was considerably higher in the urban class associated with the Inner Suburbs, where 1940-1960 era housing dominates, vegetation cover is moderate, and population density is moderate. The land cover mapping approach played an important role in the successful and consistent classification of the urban areas. The analysis demonstrates how urban form and past land use decisions can influence transmission of a vector-borne virus. In addition, the results are helpful to develop hypotheses regarding urban landscape features and WNV transmission, they provide a structured method to stratify the urban areas to locate representative field study sites specifically for WNV, and this analysis contributes to the question of how the urban environment affects human health.
Christiana, Richard W; Davis, Marsha; Wilson, Mark G; McCarty, Frances A; Green, Gary T
2014-12-01
Young adolescents who have little interest in participating in competitive team sports are at an increased risk for physical inactivity. Noncompetitive outdoor physical activity can provide young adolescents with increased opportunities to participate in physical activities that appeal to them and have positive health effects. The purpose of this study was to examine factors related to rural young adolescents' participation in noncompetitive outdoor physical activity to inform intervention design. Young adolescents aged 10 to 14 years old (N = 1,032) from 1 rural county completed a self-administered questionnaire assessing constructs from self-determination theory (SDT) and the theory of planned behavior (TPB) related to noncompetitive outdoor physical activity. Structural equation modeling was used to examine an integrated conceptual model of hypothesized relationships among constructs. The hypothesized conceptual model provided a good fit to the data with greater perceptions of autonomy support and self-determined motivation having statistically significant positive indirect effects on participation in noncompetitive outdoor physical activity mediated by the constructs of the TPB. All direct paths in the model were statistically significant; however, the direct effect of attitudes on intention was weak (.08) and self-determined motivation had no indirect effect on intention through attitudes (.03). Constructs of SDT and TPB should be accounted for by interventions targeting noncompetitive outdoor physical activity among young adolescents. More research is needed to determine young adolescents' preferences for noncompetitive and competitive physical activity and the potential influence that noncompetitive outdoor physical activity may have on total daily physical activity.
Mattsson, Brady J.; Zipkin, Elise F.; Gardner, Beth; Blank, Peter J.; Sauer, John R.; Royle, J. Andrew
2013-01-01
Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.
Mattsson, Brady J; Zipkin, Elise F; Gardner, Beth; Blank, Peter J; Sauer, John R; Royle, J Andrew
2013-01-01
Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition.
Mattsson, Brady J.; Zipkin, Elise F.; Gardner, Beth; Blank, Peter J.; Sauer, John R.; Royle, J. Andrew
2013-01-01
Understanding interactions between mobile species distributions and landcover characteristics remains an outstanding challenge in ecology. Multiple factors could explain species distributions including endogenous evolutionary traits leading to conspecific clustering and endogenous habitat features that support life history requirements. Birds are a useful taxon for examining hypotheses about the relative importance of these factors among species in a community. We developed a hierarchical Bayes approach to model the relationships between bird species occupancy and local landcover variables accounting for spatial autocorrelation, species similarities, and partial observability. We fit alternative occupancy models to detections of 90 bird species observed during repeat visits to 316 point-counts forming a 400-m grid throughout the Patuxent Wildlife Research Refuge in Maryland, USA. Models with landcover variables performed significantly better than our autologistic and null models, supporting the hypothesis that local landcover heterogeneity is important as an exogenous driver for species distributions. Conspecific clustering alone was a comparatively poor descriptor of local community composition, but there was evidence for spatial autocorrelation in all species. Considerable uncertainty remains whether landcover combined with spatial autocorrelation is most parsimonious for describing bird species distributions at a local scale. Spatial structuring may be weaker at intermediate scales within which dispersal is less frequent, information flows are localized, and landcover types become spatially diversified and therefore exhibit little aggregation. Examining such hypotheses across species assemblages contributes to our understanding of community-level associations with conspecifics and landscape composition. PMID:23393564
Organizational Context and Capabilities for Integrating Care: A Framework for Improvement.
Evans, Jenna M; Grudniewicz, Agnes; Baker, G Ross; Wodchis, Walter P
2016-08-31
Interventions aimed at integrating care have become widespread in healthcare; however, there is significant variability in their success. Differences in organizational contexts and associated capabilities may be responsible for some of this variability. This study develops and validates a conceptual framework of organizational capabilities for integrating care, identifies which of these capabilities may be most important, and explores the mechanisms by which they influence integrated care efforts. The Context and Capabilities for Integrating Care (CCIC) Framework was developed through a literature review, and revised and validated through interviews with leaders and care providers engaged in integrated care networks in Ontario, Canada. Interviews involved open-ended questions and graphic elicitation. Quantitative content analysis was used to summarize the data. The CCIC Framework consists of eighteen organizational factors in three categories: Basic Structures, People and Values, and Key Processes. The three most important capabilities shaping the capacity of organizations to implement integrated care interventions include Leadership Approach, Clinician Engagement and Leadership, and Readiness for Change. The majority of hypothesized relationships among organizational capabilities involved Readiness for Change and Partnering, emphasizing the complexity, interrelatedness and importance of these two factors to integrated care efforts. Organizational leaders can use the framework to determine readiness to integrate care, develop targeted change management strategies, and select appropriate partners with overlapping or complementary profiles on key capabilities. Researchers may use the results to test and refine the proposed framework, with a focus on the hypothesized relationships among organizational capabilities and between organizational capabilities and performance outcomes.
Neural Mechanisms Underlying the Computation of Hierarchical Tree Structures in Mathematics
Nakai, Tomoya; Sakai, Kuniyoshi L.
2014-01-01
Whether mathematical and linguistic processes share the same neural mechanisms has been a matter of controversy. By examining various sentence structures, we recently demonstrated that activations in the left inferior frontal gyrus (L. IFG) and left supramarginal gyrus (L. SMG) were modulated by the Degree of Merger (DoM), a measure for the complexity of tree structures. In the present study, we hypothesize that the DoM is also critical in mathematical calculations, and clarify whether the DoM in the hierarchical tree structures modulates activations in these regions. We tested an arithmetic task that involved linear and quadratic sequences with recursive computation. Using functional magnetic resonance imaging, we found significant activation in the L. IFG, L. SMG, bilateral intraparietal sulcus (IPS), and precuneus selectively among the tested conditions. We also confirmed that activations in the L. IFG and L. SMG were free from memory-related factors, and that activations in the bilateral IPS and precuneus were independent from other possible factors. Moreover, by fitting parametric models of eight factors, we found that the model of DoM in the hierarchical tree structures was the best to explain the modulation of activations in these five regions. Using dynamic causal modeling, we showed that the model with a modulatory effect for the connection from the L. IPS to the L. IFG, and with driving inputs into the L. IFG, was highly probable. The intrinsic, i.e., task-independent, connection from the L. IFG to the L. IPS, as well as that from the L. IPS to the R. IPS, would provide a feedforward signal, together with negative feedback connections. We indicate that mathematics and language share the network of the L. IFG and L. IPS/SMG for the computation of hierarchical tree structures, and that mathematics recruits the additional network of the L. IPS and R. IPS. PMID:25379713
Pawlik, Joseph R; Loh, Tse-Lynn; McMurray, Steven E; Finelli, Christopher M
2013-01-01
Caribbean coral reefs have been transformed in the past few decades with the demise of reef-building corals, and sponges are now the dominant habitat-forming organisms on most reefs. Competing hypotheses propose that sponge communities are controlled primarily by predatory fishes (top-down) or by the availability of picoplankton to suspension-feeding sponges (bottom-up). We tested these hypotheses on Conch Reef, off Key Largo, Florida, by placing sponges inside and outside predator-excluding cages at sites with less and more planktonic food availability (15 m vs. 30 m depth). There was no evidence of a bottom-up effect on the growth of any of 5 sponge species, and 2 of 5 species grew more when caged at the shallow site with lower food abundance. There was, however, a strong effect of predation by fishes on sponge species that lacked chemical defenses. Sponges with chemical defenses grew slower than undefended species, demonstrating a resource trade-off between growth and the production of secondary metabolites. Surveys of the benthic community on Conch Reef similarly did not support a bottom-up effect, with higher sponge cover at the shallower depth. We conclude that the structure of sponge communities on Caribbean coral reefs is primarily top-down, and predict that removal of sponge predators by overfishing will shift communities toward faster-growing, undefended species that better compete for space with threatened reef-building corals.
Pawlik, Joseph R.; Loh, Tse-Lynn; McMurray, Steven E.; Finelli, Christopher M.
2013-01-01
Caribbean coral reefs have been transformed in the past few decades with the demise of reef-building corals, and sponges are now the dominant habitat-forming organisms on most reefs. Competing hypotheses propose that sponge communities are controlled primarily by predatory fishes (top-down) or by the availability of picoplankton to suspension-feeding sponges (bottom-up). We tested these hypotheses on Conch Reef, off Key Largo, Florida, by placing sponges inside and outside predator-excluding cages at sites with less and more planktonic food availability (15 m vs. 30 m depth). There was no evidence of a bottom-up effect on the growth of any of 5 sponge species, and 2 of 5 species grew more when caged at the shallow site with lower food abundance. There was, however, a strong effect of predation by fishes on sponge species that lacked chemical defenses. Sponges with chemical defenses grew slower than undefended species, demonstrating a resource trade-off between growth and the production of secondary metabolites. Surveys of the benthic community on Conch Reef similarly did not support a bottom-up effect, with higher sponge cover at the shallower depth. We conclude that the structure of sponge communities on Caribbean coral reefs is primarily top-down, and predict that removal of sponge predators by overfishing will shift communities toward faster-growing, undefended species that better compete for space with threatened reef-building corals. PMID:23667492
Fenollar, Pedro; Román, Sergio; Cuestas, Pedro J
2007-12-01
The prediction and explanation of academic performance and the investigation of the factors relating to the academic success and persistence of students are topics of utmost importance in higher education. The main aim of the present study is to develop and test a conceptual framework in a university context, where the effects of achievement goals, self-efficacy and class size on academic performance are hypothesized to be direct and indirect through study strategies. Participants were 553 students of different faculties from a university in Spain. Pre-existing scales were used to develop the questionnaire. Questionnaires were group-administered in 21 classes during the first 2 weeks of May (i.e. about 1 month before the final examination). At the end of the academic year, students' grades were obtained from professors of each course. Data were analysed through structural equation modelling. The results of the structural model provided support for most of the hypothesized relationships. Achievement goals and self-efficacy had no direct effects on performance, but results from the model comparison suggested that a mediational model provided a better fit to the data. Our study provides support for the key mediational role of study strategies in the effect of achievement goals and self-efficacy on academic performance. Self-efficacy seems to have the strongest indirect effect on performance. Mastery goals play a key role increasing deep processing and effort, and in turn affecting performance. Academic performance tends to diminish with increasing class size.
The self-transcendence scale: an investigation of the factor structure among nursing home patients.
Haugan, Gørill; Rannestad, Toril; Garåsen, Helge; Hammervold, Randi; Espnes, Geir Arild
2012-09-01
Self-transcendence, the ability to expand personal boundaries in multiple ways, has been found to provide well-being. The purpose of this study was to examine the dimensionality of the Norwegian version of the Self-Transcendence Scale, which comprises 15 items. Reed's empirical nursing theory of self-transcendence provided the theoretical framework; self-transcendence includes an interpersonal, intrapersonal, transpersonal, and temporal dimension. Cross-sectional data were obtained from a sample of 202 cognitively intact elderly patients in 44 Norwegian nursing homes. Exploratory factor analysis revealed two and four internally consistent dimensions of self-transcendence, explaining 35.3% (two factors) and 50.7% (four factors) of the variance, respectively. Confirmatory factor analysis indicated that the hypothesized two- and four-factor models fitted better than the one-factor model (cx (2), root mean square error of approximation, standardized root mean square residual, normed fit index, nonnormed fit index, comparative fit index, goodness-of-fit index, and adjusted goodness-of-fit index). The findings indicate self-transcendence as a multifactorial construct; at present, we conclude that the two-factor model might be the most accurate and reasonable measure of self-transcendence. This research generates insights in the application of the widely used Self-Transcendence Scale by investigating its psychometric properties by applying a confirmatory factor analysis. It also generates new research-questions on the associations between self-transcendence and well-being.
Lindegarth, M
2001-05-01
Assemblages of animals in soft-sediments were studied in relation to pontoons for mooring private boats in two estuaries near Sydney, Australia. Based on previously observed patterns around other types of artificial structures, it was predicted that assemblages of animals under pontoons would be different from those in similar areas away from pontoons. Hypotheses about overall differences in average abundance and composition between sites with and without pontoons were tested, as were hypotheses about variable differences among and within estuaries. Analyses revealed that there were fewer crustaceans under pontoons in one estuary. The most conspicuous patterns related to pontoons were, however, differences in variability among sites with pontoons compared to sites without pontoons. Differences in spatial variability were found for the overall multivariate structure using Bray-Curtis dissimilarities and for abundances of most major taxa. Total abundance was approximately 60 times more variable among sites without pontoons and number of taxa were seven times more variable among sites with pontoons. Such patterns indicate that impacts of pontoons occur at some sites but not at others. This may be explained by intrinsic differences among sites or by differences in practices for maintenance. Predictions from these two contrasting models need to be tested in order to achieve efficient management of this type of structure.
Brain structures in the sciences and humanities.
Takeuchi, Hikaru; Taki, Yasuyuki; Sekiguchi, Atsushi; Nouchi, Rui; Kotozaki, Yuka; Nakagawa, Seishu; Miyauchi, Carlos Makoto; Iizuka, Kunio; Yokoyama, Ryoichi; Shinada, Takamitsu; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Hashizume, Hiroshi; Sassa, Yuko; Kawashima, Ryuta
2015-11-01
The areas of academic interest (sciences or humanities) and area of study have been known to be associated with a number of factors associated with autistic traits. However, despite the vast amount of literature on the psychological and physiological characteristics associated with faculty membership, brain structural characteristics associated with faculty membership have never been investigated directly. In this study, we used voxel-based morphometry to investigate differences in regional gray matter volume (rGMV)/regional white matter volume (rWMV) between science and humanities students to test our hypotheses that brain structures previously robustly shown to be altered in autistic subjects are related to differences in faculty membership. We examined 312 science students (225 males and 87 females) and 179 humanities students (105 males and 74 females). Whole-brain analyses of covariance revealed that after controlling for age, sex, and total intracranial volume, the science students had significantly larger rGMV in an anatomical cluster around the medial prefrontal cortex and the frontopolar area, whereas the humanities students had significantly larger rWMV in an anatomical cluster mainly concentrated around the right hippocampus. These anatomical structures have been linked to autism in previous studies and may mediate cognitive functions that characterize differences in faculty membership. The present results may support the ideas that autistic traits and characteristics of the science students compared with the humanities students share certain characteristics from neuroimaging perspectives. This study improves our understanding of differences in faculty membership which is the link among cognition, biological factors, disorders, and education (academia).
The G-factor as a tool to learn more about bone structure and function.
Zerath, E
1999-07-01
In normal life on earth, the locomotor system is exposed to two types of stimulation: gravity (passive stimulation) and motion (active stimulation). Both permanently combine, and the interactions between locomotion and gravity induce an overall recruitment which is repeated daily and maintains the bone tissue structure within the range of constraints to which it is adapted. This range is one of the basic hypotheses underlying the mechanical concepts of bone structure control, and it has been considered as logical to assume that weightlessness of spaceflight should produce bone loss since astronauts are outside of the terrestrial gravitational field of forces, no longer relying on muscular work to change positions or move. But, thirty years after the first changes in phospho-calcium metabolism were observed in astronauts after spaceflight, current knowledge does not provide a full understanding of this pathogeny, and prove the G-factor is now considered as an essential component of the experimental tools available to study bone physiology. The study of the physiology of bone tissue usually consists in the investigation of its two fundamental roles, i.e. reservoir of inorganic elements (calcium, phosphorus, magnesium) and mechanical support for soft tissues. Together with the combined action of muscles, tendons, and ligaments, this support permits motion and locomotion. These two functions rely on a sophisticated bone tissue architecture, and on the adaptability of this structure, with modeling and remodeling processes, themselves associated with the coupled activity of specialized bone cell populations.
ERIC Educational Resources Information Center
Brown, P. Margaret; Byrnes, Linda J.; Watson, Linda M.; Raban, Bridie
2013-01-01
This study investigated the relationships between children's home literacy environments and their early hypotheses about printed words in the year prior to entering school. There were 147 children (70 girls and 77 boys: mean age 57 months, range = 47-66 months, standard deviation = 4.5 months) in the study. Results showed that the children had…
ERIC Educational Resources Information Center
Somech, Lior Y.; Elizur, Yoel
2012-01-01
Research of psychological distress (PD) needs to differentiate between anxiety/depression and hostility/suspiciousness, which are associated with different motivational systems. In this study, structural equation modeling was used to test two hypothesized models for the prediction of each facet of PD. Hypotheses were proposed about the effects of…
ERIC Educational Resources Information Center
Van Noy, Michelle; Trimble, Madeline; Jenkins, Davis; Barnett, Elisabeth; Wachen, John
2016-01-01
Objective: Some have hypothesized that community college programs are not sufficiently structured to support student success and that students would benefit from more highly structured programs. This study examines the specific ways that structure is expressed in policy and practice at representative community colleges. Method: Using data obtained…
Al-Balas, Qosay A.; Amawi, Haneen A.; Hassan, Mohammad A.; Qandil, Amjad M.; Almaaytah, Ammar M.; Mhaidat, Nizar M.
2013-01-01
Farnesyltransferase enzyme (FTase) is considered an essential enzyme in the Ras signaling pathway associated with cancer. Thus, designing inhibitors for this enzyme might lead to the discovery of compounds with effective anticancer activity. In an attempt to obtain effective FTase inhibitors, pharmacophore hypotheses were generated using structure-based and ligand-based approaches built in Discovery Studio v3.1. Knowing the presence of the zinc feature is essential for inhibitor’s binding to the active site of FTase enzyme; further customization was applied to include this feature in the generated pharmacophore hypotheses. These pharmacophore hypotheses were thoroughly validated using various procedures such as ROC analysis and ligand pharmacophore mapping. The validated pharmacophore hypotheses were used to screen 3D databases to identify possible hits. Those which were both high ranked and showed sufficient ability to bind the zinc feature in active site, were further refined by applying drug-like criteria such as Lipiniski’s “rule of five” and ADMET filters. Finally, the two candidate compounds (ZINC39323901 and ZINC01034774) were allowed to dock using CDOCKER and GOLD in the active site of FTase enzyme to optimize hit selection. PMID:24276257
Al-Balas, Qosay A; Amawi, Haneen A; Hassan, Mohammad A; Qandil, Amjad M; Almaaytah, Ammar M; Mhaidat, Nizar M
2013-05-27
Farnesyltransferase enzyme (FTase) is considered an essential enzyme in the Ras signaling pathway associated with cancer. Thus, designing inhibitors for this enzyme might lead to the discovery of compounds with effective anticancer activity. In an attempt to obtain effective FTase inhibitors, pharmacophore hypotheses were generated using structure-based and ligand-based approaches built in Discovery Studio v3.1. Knowing the presence of the zinc feature is essential for inhibitor's binding to the active site of FTase enzyme; further customization was applied to include this feature in the generated pharmacophore hypotheses. These pharmacophore hypotheses were thoroughly validated using various procedures such as ROC analysis and ligand pharmacophore mapping. The validated pharmacophore hypotheses were used to screen 3D databases to identify possible hits. Those which were both high ranked and showed sufficient ability to bind the zinc feature in active site, were further refined by applying drug-like criteria such as Lipiniski's "rule of five" and ADMET filters. Finally, the two candidate compounds (ZINC39323901 and ZINC01034774) were allowed to dock using CDOCKER and GOLD in the active site of FTase enzyme to optimize hit selection.
Derous, Davina; Mitchell, Sharon E; Wang, Lu; Green, Cara L; Wang, Yingchun; Chen, Luonan; Han, Jing-Dong J; Promislow, Daniel E L; Lusseau, David; Douglas, Alex; Speakman, John R
2017-07-31
Calorie restriction (CR) may extend longevity by modulating the mechanisms involved in aging. Different hypotheses have been proposed for its main mode of action. We quantified hepatic transcripts of male C57BL/6 mice exposed to graded levels of CR (0% to 40% CR) for three months, and evaluated the responses relative to these various hypotheses. Of the four main signaling pathways implied to be linked to the impact of CR on lifespan (insulin/insulin like growth factor 1 (IGF-1), nuclear factor-kappa beta (NF-ĸB), mechanistic target of rapamycin (mTOR) and sirtuins (SIRTs)), all the pathways except SIRT were altered in a manner consistent with increased lifespan. However, the expression levels of SIRT4 and SIRT7 were decreased with increasing levels of CR. Changes consistent with altered fuel utilization under CR may reduce reactive oxygen species production, which was paralleled by reduced protection. Downregulated major urinary protein (MUP) transcription suggested reduced reproductive investment. Graded CR had a positive effect on autophagy and xenobiotic metabolism, and was protective with respect to cancer signaling. CR had no significant effect on fibroblast growth factor-21 (FGF21) transcription but affected transcription in the hydrogen sulfide production pathway. Responses to CR were consistent with several different hypotheses, and the benefits of CR on lifespan likely reflect the combined impact on multiple aging related processes.
Derous, Davina; Mitchell, Sharon E.; Wang, Lu; Green, Cara L.; Wang, Yingchun; Chen, Luonan; Han, Jing-Dong J.; Promislow, Daniel E.L.; Lusseau, David; Douglas, Alex; Speakman, John R.
2017-01-01
Calorie restriction (CR) may extend longevity by modulating the mechanisms involved in aging. Different hypotheses have been proposed for its main mode of action. We quantified hepatic transcripts of male C57BL/6 mice exposed to graded levels of CR (0% to 40% CR) for three months, and evaluated the responses relative to these various hypotheses. Of the four main signaling pathways implied to be linked to the impact of CR on lifespan (insulin/insulin like growth factor 1 (IGF-1), nuclear factor-kappa beta (NF-ĸB), mechanistic target of rapamycin (mTOR) and sirtuins (SIRTs)), all the pathways except SIRT were altered in a manner consistent with increased lifespan. However, the expression levels of SIRT4 and SIRT7 were decreased with increasing levels of CR. Changes consistent with altered fuel utilization under CR may reduce reactive oxygen species production, which was paralleled by reduced protection. Downregulated major urinary protein (MUP) transcription suggested reduced reproductive investment. Graded CR had a positive effect on autophagy and xenobiotic metabolism, and was protective with respect to cancer signaling. CR had no significant effect on fibroblast growth factor-21 (FGF21) transcription but affected transcription in the hydrogen sulfide production pathway. Responses to CR were consistent with several different hypotheses, and the benefits of CR on lifespan likely reflect the combined impact on multiple aging related processes. PMID:28768896
Extracurricular participation among children with epilepsy in Canada.
Kamath, Sangita; Fayed, Nora; Goodman, Carly; Streiner, David L; Ronen, Gabriel M
2016-03-01
Participation in extracurricular activities creates opportunities for children to foster friendships, promote a sense of belonging, and improve physical and mental well-being. The objective of this study was to determine the relationship(s) of personal factors, seizure variables, and social supports with extracurricular participation in children with epilepsy (CWE). Baseline analysis of the QUALITÉ longitudinal study cohort of children aged 8-14 years (N=426) was conducted. Variables hypothesized to be related to the participation of CWE were classified using the International Classification of Functioning, Disability and Health according to body functions (presence of generalized tonic-clonic seizures in the past month, on/off AEDs, and seizure severity), environmental factors (perceived social support from parents and friends), and personal factors (sex, age, family structure, and family income). Analysis of variables related to extracurricular participation was conducted with regression modeling. Personal factors of age, gender, and family structure as well as body function variables of generalized tonic-clonic seizures and seizure severity were found to be the most important to extracurricular participation based on how frequently they were included in the final models (16/16 and 13/16 times, respectively). When parental support was found to be related to participation, the association was negative in 6 out of 16 models. The personal factors that are related to extracurricular participation among children with epilepsy mirror samples based on the general population, although seizures also play an important role. The relationship between perceived parental support and actual participation levels warrants further exploration. Copyright © 2015 Elsevier Inc. All rights reserved.
Brewer, Shannon K.; Worthington, Thomas A.; Zhang, Tianjioa; Logue, Daniel R.; Mittelstet, Aaron R.
2016-01-01
Truncated distributions of pelagophilic fishes have been observed across the Great Plains of North America, with water use and landscape fragmentation implicated as contributing factors. Developing conservation strategies for these species is hindered by the existence of multiple competing flow regime hypotheses related to species persistence. Our primary study objective was to compare the predicted distributions of one pelagophil, the Arkansas River Shiner Notropis girardi, constructed using different flow regime metrics. Further, we investigated different approaches for improving temporal transferability of the species distribution model (SDM). We compared four hypotheses: mean annual flow (a baseline), the 75th percentile of daily flow, the number of zero-flow days, and the number of days above 55th percentile flows, to examine the relative importance of flows during the spawning period. Building on an earlier SDM, we added covariates that quantified wells in each catchment, point source discharges, and non-native species presence to a structured variable framework. We assessed the effects on model transferability and fit by reducing multicollinearity using Spearman’s rank correlations, variance inflation factors, and principal component analysis, as well as altering the regularization coefficient (β) within MaxEnt. The 75th percentile of daily flow was the most important flow metric related to structuring the species distribution. The number of wells and point source discharges were also highly ranked. At the default level of β, model transferability was improved using all methods to reduce collinearity; however, at higher levels of β, the correlation method performed best. Using β = 5 provided the best model transferability, while retaining the majority of variables that contributed 95% to the model. This study provides a workflow for improving model transferability and also presents water-management options that may be considered to improve the conservation status of pelagophils.
Graessel, Elmar; Berth, Hendrik; Lichte, Thomas; Grau, Hannes
2014-02-20
Subjective burden is a central variable describing the situation encountered by family caregivers. The 10-item short version of the Burden Scale for Family Caregivers (BSFC-short/BSFC-s) was developed to provide an economical measure of this variable. The present study examined the reliability and validity of the BSFC-s. Comprehensive data from "the IDA project" were the basis of the calculations, which included 351 dyads and examined medical data on people with dementia, interview data from their family caregivers, and health insurance data. A factor analysis was performed to explore the structure of the BSFC-s; Cronbach's alpha was used to evaluate the internal consistency of the scale. The items were analyzed to determine the item difficulty and the discriminatory power. Construct validity was tested with five hypotheses. To establish the predictive validity of the BSFC-s, predictors of institutionalization at a follow-up time of 2.5 years were analyzed (binary logistic regression). The BSFC-s score adhered to a one-factor structure. Cronbach's alpha for the complete scale was .92. A significant increase in the BSFC-s score was observed when dementia progressed, disturbing behavior occurred more frequently, care requirements increased, and when caregivers were diagnosed with depression. Caregiver burden was the second strongest predictor of institutionalization out of a total of four significant predictors. All hypotheses that referred to the construct validity were supported. The BSFC-short with its ten items is a very economical instrument for assessing the caregiver's total subjective burden in a short time frame. The BSFC-s score has predictive validity for the institutionalization of people with dementia. Therefore it is an appropriate outcome measure to evaluate caregiver interventions. The scale is available for free in 20 languages (http://www.caregiver-burden.eu). This availability facilitates the comparison of international research findings.
Radford, Ian J.; Dickman, Christopher R.; Start, Antony N.; Palmer, Carol; Carnes, Karin; Everitt, Corrin; Fairman, Richard; Graham, Gordon; Partridge, Thalie; Thomson, Allan
2014-01-01
We construct a state-and-transition model for mammals in tropical savannas in northern Australia to synthesize ecological knowledge and understand mammalian declines. We aimed to validate the existence of alternative mammal assemblage states similar to those in arid Australian grasslands, and to speculate on transition triggers. Based on the arid grassland model, we hypothesized that assemblages are partitioned across rainfall gradients and between substrates. We also predicted that assemblages typical of arid regions in boom periods would be prevalent in savannas with higher and more regular rainfall. Data from eight mammal surveys from the Kimberley region, Western Australia (1994 to 2011) were collated. Survey sites were partitioned across rainfall zones and habitats. Data allowed us to identify three assemblage states: State 0:- low numbers of mammals, State II:- dominated by omnivorous rodents and State III:- dominated by rodents and larger marsupials. Unlike arid grasslands, assemblage dominance by insectivorous dasyurids (State I) did not occur in savannas. Mammal assemblages were partitioned across rainfall zones and between substrates as predicted, but—unlike arid regions—were not related strongly to yearly rainfall. Mammal assemblage composition showed high regional stability, probably related to high annual rainfall and predictable wet season resource pulses. As a consequence, we speculate that perpetually booming assemblages in savannas allow top-down control of the ecosystem, with suppression of introduced cats by the dingo, the region's top predator. Under conditions of low or erratic productivity, imposed increasingly by intense fire regimes and introduced herbivore grazing, dingoes may not limit impacts of cats on native mammals. These interacting factors may explain contemporary declines of savanna mammals as well as historical declines in arid Australia. The cat-ecosystem productivity hypothesis raised here differs from the already-articulated cat-habitat structure hypothesis for mammal declines, and we suggest approaches for explicit testing of transition triggers for competing hypotheses. PMID:24670997
Radford, Ian J; Dickman, Christopher R; Start, Antony N; Palmer, Carol; Carnes, Karin; Everitt, Corrin; Fairman, Richard; Graham, Gordon; Partridge, Thalie; Thomson, Allan
2014-01-01
We construct a state-and-transition model for mammals in tropical savannas in northern Australia to synthesize ecological knowledge and understand mammalian declines. We aimed to validate the existence of alternative mammal assemblage states similar to those in arid Australian grasslands, and to speculate on transition triggers. Based on the arid grassland model, we hypothesized that assemblages are partitioned across rainfall gradients and between substrates. We also predicted that assemblages typical of arid regions in boom periods would be prevalent in savannas with higher and more regular rainfall. Data from eight mammal surveys from the Kimberley region, Western Australia (1994 to 2011) were collated. Survey sites were partitioned across rainfall zones and habitats. Data allowed us to identify three assemblage states: State 0:--low numbers of mammals, State II:--dominated by omnivorous rodents and State III:--dominated by rodents and larger marsupials. Unlike arid grasslands, assemblage dominance by insectivorous dasyurids (State I) did not occur in savannas. Mammal assemblages were partitioned across rainfall zones and between substrates as predicted, but-unlike arid regions-were not related strongly to yearly rainfall. Mammal assemblage composition showed high regional stability, probably related to high annual rainfall and predictable wet season resource pulses. As a consequence, we speculate that perpetually booming assemblages in savannas allow top-down control of the ecosystem, with suppression of introduced cats by the dingo, the region's top predator. Under conditions of low or erratic productivity, imposed increasingly by intense fire regimes and introduced herbivore grazing, dingoes may not limit impacts of cats on native mammals. These interacting factors may explain contemporary declines of savanna mammals as well as historical declines in arid Australia. The cat-ecosystem productivity hypothesis raised here differs from the already-articulated cat-habitat structure hypothesis for mammal declines, and we suggest approaches for explicit testing of transition triggers for competing hypotheses.
2017-01-01
Understanding how individual photoreceptor cells factor in the spectral sensitivity of a visual system is essential to explain how they contribute to the visual ecology of the animal in question. Existing methods that model the absorption of visual pigments use templates which correspond closely to data from thin cross-sections of photoreceptor cells. However, few modeling approaches use a single framework to incorporate physical parameters of real photoreceptors, which can be fused, and can form vertical tiers. Akaike’s information criterion (AICc) was used here to select absorptance models of multiple classes of photoreceptor cells that maximize information, given visual system spectral sensitivity data obtained using extracellular electroretinograms and structural parameters obtained by histological methods. This framework was first used to select among alternative hypotheses of photoreceptor number. It identified spectral classes from a range of dark-adapted visual systems which have between one and four spectral photoreceptor classes. These were the velvet worm, Principapillatus hitoyensis, the branchiopod water flea, Daphnia magna, normal humans, and humans with enhanced S-cone syndrome, a condition in which S-cone frequency is increased due to mutations in a transcription factor that controls photoreceptor expression. Data from the Asian swallowtail, Papilio xuthus, which has at least five main spectral photoreceptor classes in its compound eyes, were included to illustrate potential effects of model over-simplification on multi-model inference. The multi-model framework was then used with parameters of spectral photoreceptor classes and the structural photoreceptor array kept constant. The goal was to map relative opsin expression to visual pigment concentration. It identified relative opsin expression differences for two populations of the bluefin killifish, Lucania goodei. The modeling approach presented here will be useful in selecting the most likely alternative hypotheses of opsin-based spectral photoreceptor classes, using relative opsin expression and extracellular electroretinography. PMID:28740757
Chapman, C Richard; Vierck, Charles J
2017-04-01
The nature of the transition from acute to chronic pain still eludes explanation, but chronic pain resulting from surgery provides a natural experiment that invites clinical epidemiological investigation and basic scientific inquiry into the mechanisms of this transition. The primary purpose of this article is to review current knowledge and hypotheses on the transition from acute to persistent postsurgical pain, summarizing literature on clinical epidemiological studies of persistent postsurgical pain development, as well as basic neurophysiological studies targeting mechanisms in the periphery, spinal cord, and brain. The second purpose of this article is to integrate theory, information, and causal reasoning in these areas. Conceptual mapping reveals 5 classes of hypotheses pertaining to pain. These propose that chronic pain results from: 1) persistent noxious signaling in the periphery; 2) enduring maladaptive neuroplastic changes at the spinal dorsal horn and/or higher central nervous system structures reflecting a multiplicity of factors, including peripherally released neurotrophic factors and interactions between neurons and microglia; 3) compromised inhibitory modulation of noxious signaling in medullary-spinal pathways; 4) descending facilitatory modulation; and 5) maladaptive brain remodeling in function, structure, and connectivity. The third purpose of this article is to identify barriers to progress and review opportunities for advancing the field. This review reveals a need for a concerted, strategic effort toward integrating clinical epidemiology, basic science research, and current theory about pain mechanisms to hasten progress toward understanding, managing, and preventing persistent postsurgical pain. The development of chronic pain after surgery is a major clinical problem that provides an opportunity to study the transition from acute to chronic pain at epidemiologic and basic science levels. Strategic, coordinated, multidisciplinary research efforts targeting mechanisms of pain chronification can to help minimize or eliminate persistent postsurgical pain. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.
Lessios, Nicolas
2017-01-01
Understanding how individual photoreceptor cells factor in the spectral sensitivity of a visual system is essential to explain how they contribute to the visual ecology of the animal in question. Existing methods that model the absorption of visual pigments use templates which correspond closely to data from thin cross-sections of photoreceptor cells. However, few modeling approaches use a single framework to incorporate physical parameters of real photoreceptors, which can be fused, and can form vertical tiers. Akaike's information criterion (AIC c ) was used here to select absorptance models of multiple classes of photoreceptor cells that maximize information, given visual system spectral sensitivity data obtained using extracellular electroretinograms and structural parameters obtained by histological methods. This framework was first used to select among alternative hypotheses of photoreceptor number. It identified spectral classes from a range of dark-adapted visual systems which have between one and four spectral photoreceptor classes. These were the velvet worm, Principapillatus hitoyensis , the branchiopod water flea, Daphnia magna , normal humans, and humans with enhanced S-cone syndrome, a condition in which S-cone frequency is increased due to mutations in a transcription factor that controls photoreceptor expression. Data from the Asian swallowtail, Papilio xuthus , which has at least five main spectral photoreceptor classes in its compound eyes, were included to illustrate potential effects of model over-simplification on multi-model inference. The multi-model framework was then used with parameters of spectral photoreceptor classes and the structural photoreceptor array kept constant. The goal was to map relative opsin expression to visual pigment concentration. It identified relative opsin expression differences for two populations of the bluefin killifish, Lucania goodei . The modeling approach presented here will be useful in selecting the most likely alternative hypotheses of opsin-based spectral photoreceptor classes, using relative opsin expression and extracellular electroretinography.
Wang, Jong-Yi; Li, Yi-Shan; Chen, Jen-De; Liang, Wen-Miin; Yang, Tung-Chuan; Lee, Young-Chang; Wang, Chia-Woei
2015-01-01
Patients with infertility are a high risk group in depression and anxiety. However, an existing theoretically and empirically validated model of stressors, stress, and mental symptoms specific for infertile patients is still a void. This study aimed to determine the related factors and their relational structures that affect the level of depressive and anxiety symptoms among infertile patients. A cross-sectional sample of 400 infertility outpatients seeking reproduction treatments in three teaching hospitals across Taiwan participated in the structured questionnaire survey in 2011. The hypothesized model comprising 10 latent variables was tested by Structural Equation Modeling using AMOS 17. Goodness-of-fit indexes, including χ2/DF = 1.871, PGFI = 0.746, PNFI = 0.764, and others, confirmed the modified model fit the data well. Marital stressor, importance of children, guilt-and-blame, and social stressor showed a direct effect on perceived stress. Instead of being a factor of stress, social support was directly and positively related to self-esteem. Perceived stress and self-esteem were the two major mediators for the relationships between stressors and mental symptoms. Increase in social support and self-esteem led to decrease in mental symptoms among the infertile patients. The relational structures were identified and named as the Stressors Stress Symptoms Model, clinically applied to predict anxiety and depression from various stressors. Assessing sources and level of infertility-related stress and implementing culturally-sensitive counseling with an emphasis on positive personal value may assist in preventing the severity of depression and anxiety.
Wang, Jong-Yi; Liang, Wen-Miin; Yang, Tung-Chuan; Lee, Young-Chang; Wang, Chia-Woei
2015-01-01
Objective Patients with infertility are a high risk group in depression and anxiety. However, an existing theoretically and empirically validated model of stressors, stress, and mental symptoms specific for infertile patients is still a void. This study aimed to determine the related factors and their relational structures that affect the level of depressive and anxiety symptoms among infertile patients. Methods A cross-sectional sample of 400 infertility outpatients seeking reproduction treatments in three teaching hospitals across Taiwan participated in the structured questionnaire survey in 2011. The hypothesized model comprising 10 latent variables was tested by Structural Equation Modeling using AMOS 17. Results Goodness-of-fit indexes, including χ2/DF = 1.871, PGFI = 0.746, PNFI = 0.764, and others, confirmed the modified model fit the data well. Marital stressor, importance of children, guilt-and-blame, and social stressor showed a direct effect on perceived stress. Instead of being a factor of stress, social support was directly and positively related to self-esteem. Perceived stress and self-esteem were the two major mediators for the relationships between stressors and mental symptoms. Increase in social support and self-esteem led to decrease in mental symptoms among the infertile patients. Conclusions The relational structures were identified and named as the Stressors Stress Symptoms Model, clinically applied to predict anxiety and depression from various stressors. Assessing sources and level of infertility-related stress and implementing culturally-sensitive counseling with an emphasis on positive personal value may assist in preventing the severity of depression and anxiety. PMID:26484531
A Dual-Driver Model of Retention and Turnover in the Direct Care Workforce
ERIC Educational Resources Information Center
Mittal, Vikas; Rosen, Jules; Leana, Carrie
2009-01-01
Purpose: The purpose of this study was to understand the factors associated with turnover and retention of direct care workers. We hypothesize that a dual-driver model that includes individual factors, on-the-job factors, off-the-job factors, and contextual factors can be used to distinguish between reasons for direct care workforces (DCWs)…
Religiosity, social support, and life satisfaction among elderly Korean immigrants.
Park, Jisung; Roh, Soonhee; Yeo, Younsook
2012-10-01
The present study tested Smith's (2003. Theorizing religious effects among American adolescents. Journal for the Scientific Study of Religion, 42, 17-30. doi:10.1111/1468-5906.t01-1-00158) theory of religious effects to explore the relationship of religiosity, social support, and life satisfaction among elderly Korean immigrants. The study investigated the mediating role of social support to the relationship between religiosity and life satisfaction. We hypothesized that religiosity would be positively associated with life satisfaction and that the relationship between religiosity and life satisfaction would be mediated by social support. Structural equation modeling was used to test the proposed hypotheses with a sample of 200 Korean immigrant older adults in New York City (mean age = 72.5, range = 65-89). We found that greater religiosity was related to greater life satisfaction and that social support partially explained the positive relationship between religiosity and life satisfaction. Results indicated that religious engagement and social support could be significant factors to improve the quality of life among elderly Korean immigrants. Social services that facilitate religiosity and social support may be beneficial for Korean elders' life satisfaction. Future studies are invited to replicate this study for diverse ethnic groups of elderly immigrants.
Increasing elevation of fire in the Sierra Nevada and implications for forest change
Schwartz, Mark W.; Butt, Nathalie; Dolanc, Christopher R.; Holguin, Andrew; Moritz, Max A.; North, Malcolm P.; Safford, Hugh D.; Stephenson, Nathan L.; Thorne, James H.; van Mantgem, Phillip J.
2015-01-01
Fire in high-elevation forest ecosystems can have severe impacts on forest structure, function and biodiversity. Using a 105-year data set, we found increasing elevation extent of fires in the Sierra Nevada, and pose five hypotheses to explain this pattern. Beyond the recognized pattern of increasing fire frequency in the Sierra Nevada since the late 20th century, we find that the upper elevation extent of those fires has also been increasing. Factors such as fire season climate and fuel build up are recognized potential drivers of changes in fire regimes. Patterns of warming climate and increasing stand density are consistent with both the direction and magnitude of increasing elevation of wildfire. Reduction in high elevation wildfire suppression and increasing ignition frequencies may also contribute to the observed pattern. Historical biases in fire reporting are recognized, but not likely to explain the observed patterns. The four plausible mechanistic hypotheses (changes in fire management, climate, fuels, ignitions) are not mutually exclusive, and likely have synergistic interactions that may explain the observed changes. Irrespective of mechanism, the observed pattern of increasing occurrence of fire in these subalpine forests may have significant impacts on their resilience to changing climatic conditions.
The body unbound: vestibular-motor hallucinations and out-of-body experiences.
Cheyne, J Allan; Girard, Todd A
2009-02-01
Among the varied hallucinations associated with sleep paralysis (SP), out-of-body experiences (OBEs) and vestibular-motor (V-M) sensations represent a distinct factor. Recent studies of direct stimulation of vestibular cortex report a virtually identical set of bodily-self hallucinations. Both programs of research agree on numerous details of OBEs and V-M experiences and suggest similar hypotheses concerning their association. In the present study, self-report data from two on-line surveys of SP-related experiences were employed to assess hypotheses concerning the causal structure of relations among V-M experiences and OBEs during SP episodes. The results complement neurophysiological evidence and are consistent with the hypothesis that OBEs represent a breakdown in the normal binding of bodily-self sensations and suggest that out-of-body feelings (OBFs) are consequences of anomalous V-M experiences and precursors to a particular form of autoscopic experience, out-of-body autoscopy (OBA). An additional finding was that vestibular and motor experiences make relatively independent contributions to OBE variance. Although OBEs are superficially consistent with universal dualistic and supernatural intuitions about the nature of the soul and its relation to the body, recent research increasingly offers plausible alternative naturalistic explanations of the relevant phenomenology.
Satellite DNA: An Evolving Topic
Garrido-Ramos, Manuel A.
2017-01-01
Satellite DNA represents one of the most fascinating parts of the repetitive fraction of the eukaryotic genome. Since the discovery of highly repetitive tandem DNA in the 1960s, a lot of literature has extensively covered various topics related to the structure, organization, function, and evolution of such sequences. Today, with the advent of genomic tools, the study of satellite DNA has regained a great interest. Thus, Next-Generation Sequencing (NGS), together with high-throughput in silico analysis of the information contained in NGS reads, has revolutionized the analysis of the repetitive fraction of the eukaryotic genomes. The whole of the historical and current approaches to the topic gives us a broad view of the function and evolution of satellite DNA and its role in chromosomal evolution. Currently, we have extensive information on the molecular, chromosomal, biological, and population factors that affect the evolutionary fate of satellite DNA, knowledge that gives rise to a series of hypotheses that get on well with each other about the origin, spreading, and evolution of satellite DNA. In this paper, I review these hypotheses from a methodological, conceptual, and historical perspective and frame them in the context of chromosomal organization and evolution. PMID:28926993
Information Content Moderates Positivity and Negativity Biases in Memory
Hess, Thomas M.; Popham, Lauren E.; Dennis, Paul A.; Emery, Lisa
2014-01-01
Two experiments examined the impact of encoding conditions and information content in memory for positive, neutral, and negative pictures. We examined the hypotheses that the positivity effect in memory (i.e., a bias in favor of positive or against negative information in later life) would be reduced when (a) pictures were viewed under structured as opposed to unstructured conditions, and (b) contained social as opposed to nonsocial content. Both experiments found that the positivity effect observed with nonsocial stimuli was absent with social stimuli. In addition, little evidence was obtained that encoding conditions affected the strength of the positivity effect. We argue that some types of social stimuli may engage different types of processing than nonsocial stimuli, perhaps encouraging self-referential processing that engages attention and supports memory. This processing may then conflict with the goal-driven, top-down processing that is hypothesized to drive the positivity effect. Thus, our results identify further boundary conditions associated with the positivity effect in memory, arguing that stimulus factors as well as situational goals may affect its occurrence. Further research awaits to determine if this effect is specific to all social stimuli or specific subsets. PMID:23421322
Information content moderates positivity and negativity biases in memory.
Hess, Thomas M; Popham, Lauren E; Dennis, Paul A; Emery, Lisa
2013-09-01
Two experiments examined the impact of encoding conditions and information content in memory for positive, neutral, and negative pictures. We examined the hypotheses that the positivity effect in memory (i.e., a bias in favor of positive or against negative information in later life) would be reduced when (a) pictures were viewed under structured as opposed to unstructured conditions, and (b) contained social as opposed to nonsocial content. Both experiments found that the positivity effect observed with nonsocial stimuli was absent with social stimuli. In addition, little evidence was obtained that encoding conditions affected the strength of the positivity effect. We argue that some types of social stimuli may engage different types of processing than nonsocial stimuli, perhaps encouraging self-referential processing that engages attention and supports memory. This processing may then conflict with the goal-driven, top-down processing that is hypothesized to drive the positivity effect. Thus, our results identify further boundary conditions associated with the positivity effect in memory, arguing that stimulus factors as well as situational goals may affect its occurrence. Further research awaits to determine if this effect is specific to all social stimuli or specific subsets.
Dimensionality and Transcultural Specificity of the Sexual Attraction Questionnaire (SAQ).
Fernández, Juan; Quiroga, María Angeles; Icaza, Vanessa J; Escorial, Sergio
2012-03-01
Sexual attraction was considered a component of sexual orientation from the beginning of the second half of the 20th century to present times. However, some recent researchers have studied sexual attraction as an independent field measuring it by the Sexual Attraction Questionnaire (SAQ). This study analyzes sexual attraction through the SAQ in 400 university students from a Peruvian catholic university. These participants -191 women and 209 men- show a very diverse curricular background. The following hypotheses were tested: a) the structure of the SAQ, pointing out two concepts: attraction to men and attraction to women; b) the high inverse correlation between these two concepts or factors; c) the specific impact of this context in sexual attraction: higher percentage of attracted by none of the sexes and lower percentage of attracted to the opposite sex, in comparison with other contexts; and d) the Lippa prediction (2006, 2007), regarding a higher polarization of sexual attraction for men than for women. Results support the first three hypotheses. Clarifications are laid down with regard to the fourth one. Discussion focuses on theoretical and applied advantages of using the SAQ as opposed to the frequent use of a single item of sexual attraction for each sex.
Testing a Model of Functional Impairment in Telephone Crisis Support Workers.
Kitchingman, Taneile A; Wilson, Coralie J; Caputi, Peter; Wilson, Ian; Woodward, Alan
2017-11-01
It is well known that helping professionals experience functional impairment related to elevated symptoms of psychological distress as a result of frequent empathic engagement with distressed others. Whether telephone crisis support workers are impacted in a similar way is not currently reported in the literature. The purpose of this study was to test a hypothesized model of factors contributing to functional impairment in telephone crisis support workers. A national sample of 210 telephone crisis support workers completed an online survey including measures of emotion regulation, symptoms of general psychological distress and suicidal ideation, intentions to seek help for symptoms, and functional impairment. Structural equation modeling was used to test the fit of the data to the hypothesized model. Goodness-of-fit indices were adequate and supported the interactive effects of emotion regulation, general psychological distress, suicidal ideation, and intentions to seek help for ideation on functional impairment. These results warrant the deliberate management of telephone crisis support workers' impairment through service selection, training, supervision, and professional development strategies. Future research replicating and extending this model will further inform the modification and/or development of strategies to optimize telephone crisis support workers' well-being and delivery of support to callers.
The Tsenkher Structure in the Gobi-Altai, Mongolia: Preliminary Results from the 2007 Expedition
NASA Astrophysics Data System (ADS)
Komatsu, G.; Ormö, J.; Bayaraa, T.; Matsui, T.; Gereltsetseg, L.; Tserendug, S.; Goto, K.; Gomez-Ortiz, D.; Demberel, S.
2008-03-01
The 3.6-3.7 km Tsenkher structure located in Mongolia was proposed to be an impact crater. Volcanic hypotheses are not ruled out, but its uplifted rim, extensive breccia deposit, and rootless structure are consistent with an impact origin.
Predisposition Factors in Anorexia Nervosa.
ERIC Educational Resources Information Center
Nagel, K. L.; Jones, Karen H.
1992-01-01
Reviews literature concerned with investigating psychiatric disturbances and genetic variables hypothesized as predisposing factors in etiology of anorexia nervosa. Gives particular emphasis to research which discusses association between anorexia nervosa and depression. Reviews psychopharmacological evidence and family genetics studies. Offers…
Perceptual Factors and Learning in Digital Environments
ERIC Educational Resources Information Center
Paek, Seungoh; Hoffman, Daniel L.; Black, John B.
2016-01-01
The purpose of this study was to examine if student understanding of new material could be promoted by manipulating the perceptual factors experienced at the time of learning. It was hypothesized that the thematic relevance of perceptual factors would be a significant contributor to learner understanding. To test this hypothesis, one hundred…
Multilevel Confirmatory Factor Analysis of the Teacher My Class Inventory-Short Form
ERIC Educational Resources Information Center
Villares, Elizabeth; Mariani, Melissa; Sink, Christopher A.; Colvin, Kimberly
2016-01-01
Researchers analyzed data from elementary teachers (N = 233) to further establish the psychometric soundness of the Teacher My Class Inventory-Short Form. Supporting previous psychometric research, confirmatory factor analyses findings supported the factorial validity of the hypothesized five-factor solution. Internal reliability estimates were…
Maternal Early Life Experiences and Parenting: The Mediating Role of Cortisol and Executive Function
ERIC Educational Resources Information Center
Gonzalez, Andrea; Jenkins, Jennifer M.; Steiner, Meir; Fleming, Alison S.
2012-01-01
Objective: Research suggests that early life adversity may affect subsequent parenting. Animal studies investigating mechanisms of transmission have focused on biological factors; whereas research in humans has emphasized cognitive and psychosocial factors. We hypothesized that neuropsychological and physiological factors would act as mediators…
Sanchez, Delida; Whittaker, Tiffany A; Hamilton, Emma; Zayas, Luis H
2016-07-01
This study explored the relation between perceived discrimination and sexual precursor behaviors among 205 Mexican American preadolescent middle school girls. In addition, this study examined whether psychological distress and sexual attitudes mediated and whether marianismo beliefs moderated this relation. A categorical confirmatory factor analysis (CCFA) of the Marianismo Beliefs Scale (MBS) was conducted to test the factor structure with a preadolescent Mexican American population (ages 11-14). A path analysis of analytic models was then performed to examine the hypothesized relations between perceived discrimination, psychological distress, sexual attitudes, marianismo beliefs, and sexual precursor behaviors. Results of the CCFA did not support the original 5-factor structure of the MBS for preadolescent Latina girls. However, a revised version of the MBS indicated an acceptable model fit, and findings from the path analysis indicated that perceived discrimination was both directly and indirectly linked to sexual precursor behaviors via psychological distress. Marianismo was not found to moderate the relation between perceived discrimination and sexual risk behaviors, however certain marianismo pillars were significantly negatively linked with sexual attitudes and precursor behaviors. This study underscores the importance of psychological distress in the perceived discrimination and sexual precursor link as well as the compensatory aspects of marianismo against sexual precursor behaviors in Mexican American preadolescent girls. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Scaling methane oxidation: From laboratory incubation experiments to landfill cover field conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abichou, Tarek, E-mail: abichou@eng.fsu.edu; Mahieu, Koenraad; Chanton, Jeff
2011-05-15
Evaluating field-scale methane oxidation in landfill cover soils using numerical models is gaining interest in the solid waste industry as research has made it clear that methane oxidation in the field is a complex function of climatic conditions, soil type, cover design, and incoming flux of landfill gas from the waste mass. Numerical models can account for these parameters as they change with time and space under field conditions. In this study, we developed temperature, and water content correction factors for methane oxidation parameters. We also introduced a possible correction to account for the different soil structure under field conditions.more » These parameters were defined in laboratory incubation experiments performed on homogenized soil specimens and were used to predict the actual methane oxidation rates to be expected under field conditions. Water content and temperature corrections factors were obtained for the methane oxidation rate parameter to be used when modeling methane oxidation in the field. To predict in situ measured rates of methane with the model it was necessary to set the half saturation constant of methane and oxygen, K{sub m}, to 5%, approximately five times larger than laboratory measured values. We hypothesize that this discrepancy reflects differences in soil structure between homogenized soil conditions in the lab and actual aggregated soil structure in the field. When all of these correction factors were re-introduced into the oxidation module of our model, it was able to reproduce surface emissions (as measured by static flux chambers) and percent oxidation (as measured by stable isotope techniques) within the range measured in the field.« less
ERIC Educational Resources Information Center
Ullrich, Simone; Coid, Jeremy
2011-01-01
Objective: There is a substantial body of research on risk factors for violent behavior in adulthood but little empirical study of protective factors and desistance. Method: This study aimed to investigate the protective effects of factors hypothesized to reduce violent reoffending among a sample of 800 male prisoners following release into the…
Lenticular nucleus correlates of general self-efficacy in young adults.
Nakagawa, Seishu; Takeuchi, Hikaru; Taki, Yasuyuki; Nouchi, Rui; Kotozaki, Yuka; Shinada, Takamitsu; Maruyama, Tsukasa; Sekiguchi, Atsushi; Iizuka, Kunio; Yokoyama, Ryoichi; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Miyauchi, Carlos Makoto; Magistro, Daniele; Sakaki, Kohei; Jeong, Hyeonjeong; Sasaki, Yukako; Kawashima, Ryuta
2017-09-01
General self-efficacy (GSE) is an important factor in education, social participation, and medical treatment. However, the only study that has investigated the direct association between GSE and a neural correlate did not identify specific brain regions, rather only assessed brain structures, and included older adult subjects. GSE is related to motivation, physical activity, learning, the willingness to initiate behaviour and expend effort, and adjustment. Thus, it was hypothesized in the present study that the neural correlates of GSE might be related to changes in the basal ganglia, which is a region related to the abovementioned self-efficacy factors. This study aimed to identify the brain structures associated with GSE in healthy young adults (n = 1204, 691 males and 513 females, age 20.7 ± 1.8 years) using regional grey matter density and volume (rGMD and rGMV), fractional anisotropy (FA) and mean diffusivity (MD) analyses of magnetic resonance imaging (MRI) data. The findings showed that scores on the GSE Scale (GSES) were associated with a lower MD value in regions from the right putamen to the globus pallidum; however, there were no significant association between GSES scores and regional brain structures using the other analyses (rGMD, rGMV, and FA). Thus, the present findings indicated that the lenticular nucleus is a neural correlate of GSE.
Hankin, Benjamin L.; Snyder, Hannah R.; Gulley, Lauren D.; Schweizer, Tina H.; Bijttebier, Patricia; Nelis, Sabine; Toh, Gim; Vasey, Michael W.
2016-01-01
It is well known that comorbidity is the rule, not the exception, for categorically defined psychiatric disorders, and this is also the case for internalizing disorders of depression and anxiety. This theoretical review paper addresses the ubiquity of comorbidity among internalizing disorders. Our central thesis is that progress in understanding this co-occurrence can be made by employing latent dimensional structural models that organize both psychopathology as well as vulnerabilities and risk mechanisms and by connecting the multiple levels of risk and psychopathology outcomes together. Different vulnerabilities and risk mechanisms are hypothesized to predict different levels of the structural model of psychopathology. We review the present state of knowledge based on concurrent and developmental sequential comorbidity patterns among common discrete psychiatric disorders in youth, and then we advocate for the use of more recent bifactor dimensional models of psychopathology (e.g., p factor, Caspi et al., 2014) that can help to explain the co-occurrence among internalizing symptoms. In support of this relatively novel conceptual perspective, we review six exemplar vulnerabilities and risk mechanisms, including executive function, information processing biases, cognitive vulnerabilities, positive and negative affectivity aspects of temperament, and autonomic dysregulation, along with the developmental occurrence of stressors in different domains, to show how these vulnerabilities can predict the general latent psychopathology factor, a unique latent internalizing dimension, as well as specific symptom syndrome manifestations. PMID:27739389
Exposure assessment for endocrine disruptors: some considerations in the design of studies.
Rice, Carol; Birnbaum, Linda S; Cogliano, James; Mahaffey, Kathryn; Needham, Larry; Rogan, Walter J; vom Saal, Frederick S
2003-01-01
In studies designed to evaluate exposure-response relationships in children's development from conception through puberty, multiple factors that affect the generation of meaningful exposure metrics must be considered. These factors include multiple routes of exposure; the timing, frequency, and duration of exposure; need for qualitative and quantitative data; sample collection and storage protocols; and the selection and documentation of analytic methods. The methods for exposure data collection and analysis must be sufficiently robust to accommodate the a priori hypotheses to be tested, as well as hypotheses generated from the data. A number of issues that must be considered in study design are summarized here. PMID:14527851
ERIC Educational Resources Information Center
Asbury, Kathryn; Dunn, Judy; Plomin, Robert
2006-01-01
Non-shared environmental influence (NSE) has been found to account for around 50 percent of anxiety variance, but specific NSE factors have not been identified. Discordant monozygotic (MZ) twins can be used to generate relevant hypotheses because MZ discordance can be caused by NSE, but not by genes or shared environment. Of 1590 MZ pairs teacher…
Intra Articular Therapeutic Delivery for Post Traumatic Osteoarthritis
2016-10-01
method. Our central hypotheses are that joint retention time and therapeutic efficacy will be influenced by amniotic membrane particle size ...three Specific Aims: Aim 1: Evaluate the effects of human amniotic membrane (AM) particle size distribution on particle retention and progression of OA...following trauma. Factors we hypothesized would impact therapeutic efficacy of dHACM included particle size , timing of treatment, and frequency of delivery
Structural diversity promotes productivity of mixed, uneven-aged forests in southwestern Germany.
Dănescu, Adrian; Albrecht, Axel T; Bauhus, Jürgen
2016-10-01
Forest diversity-productivity relationships have been intensively investigated in recent decades. However, few studies have considered the interplay between species and structural diversity in driving productivity. We analyzed these factors using data from 52 permanent plots in southwestern Germany with more than 53,000 repeated tree measurements. We used basal area increment as a proxy for productivity and hypothesized that: (1) structural diversity would increase tree and stand productivity, (2) diversity-productivity relationships would be weaker for species diversity than for structural diversity, and (3) species diversity would also indirectly impact stand productivity via changes in size structure. We measured diversity using distance-independent indices. We fitted separate linear mixed-effects models for fir, spruce and beech at the tree level, whereas at the stand level we pooled all available data. We tested our third hypothesis using structural equation modeling. Structural and species diversity acted as direct and independent drivers of stand productivity, with structural diversity being a slightly better predictor. Structural diversity, but not species diversity, had a significant, albeit asymmetric, effect on tree productivity. The functioning of structurally diverse, mixed forests is influenced by both structural and species diversity. These sources of trait diversity contribute to increased vertical stratification and crown plasticity, which in turn diminish competitive interferences and lead to more densely packed canopies per unit area. Our research highlights the positive effects of species diversity and structural diversity on forest productivity and ecosystem dynamics.
Factors affecting construction performance: exploratory factor analysis
NASA Astrophysics Data System (ADS)
Soewin, E.; Chinda, T.
2018-04-01
The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.
Problem-solving skills and hardiness as protective factors against stress in Iranian nurses.
Abdollahi, Abbas; Talib, Mansor Abu; Yaacob, Siti Nor; Ismail, Zanariah
2014-02-01
Nursing is a stressful occupation, even when compared with other health professions; therefore, it is necessary to advance our knowledge about the protective factors that can help reduce stress among nurses. The present study sought to investigate the associations among problem-solving skills and hardiness with perceived stress in nurses. The participants, 252 nurses from six private hospitals in Tehran, completed the Personal Views Survey, the Perceived Stress Scale, and the Problem-Solving Inventory. Structural Equation Modeling (SEM) was used to analyse the data and answer the research hypotheses. As expected, greater hardiness was associated with low levels of perceived stress, and nurses low in perceived stress were more likely to be considered approachable, have a style that relied on their own sense of internal personal control, and demonstrate effective problem-solving confidence. These findings reinforce the importance of hardiness and problem-solving skills as protective factors against perceived stress among nurses, and could be important in training future nurses so that hardiness ability and problem-solving skills can be imparted, allowing nurses to have more ability to control their perceived stress.
Human performance interfaces in air traffic control.
Chang, Yu-Hern; Yeh, Chung-Hsing
2010-01-01
This paper examines how human performance factors in air traffic control (ATC) affect each other through their mutual interactions. The paper extends the conceptual SHEL model of ergonomics to describe the ATC system as human performance interfaces in which the air traffic controllers interact with other human performance factors including other controllers, software, hardware, environment, and organisation. New research hypotheses about the relationships between human performance interfaces of the system are developed and tested on data collected from air traffic controllers, using structural equation modelling. The research result suggests that organisation influences play a more significant role than individual differences or peer influences on how the controllers interact with the software, hardware, and environment of the ATC system. There are mutual influences between the controller-software, controller-hardware, controller-environment, and controller-organisation interfaces of the ATC system, with the exception of the controller-controller interface. Research findings of this study provide practical insights in managing human performance interfaces of the ATC system in the face of internal or external change, particularly in understanding its possible consequences in relation to the interactions between human performance factors.
Zapolski, Tamika C. B.; Garcia, Crystal A.; Jarjoura, G. Roger; Lau, Katherine S. L.; Aalsma, Matthew C.
2016-01-01
Risk assessment instruments are commonly used within the juvenile justice system to estimate a juvenile's likelihood of reoffending or engaging in aggressive or violent behavior. Although such instruments assess a broad range of factors, the influence of culture is often excluded. The current study examines the unique effect of ethnic/racial socialization on recent aggressive behaviors above and beyond three well-established risk and protective factors: delinquency history, moral disengagement, and social support. Participants were 95 juveniles who were either on probation or in detention centers in three Midwestern counties and who completed structured surveys related to personal experiences within and outside of the juvenile justice system. The findings provided partial support for our hypotheses: Consistent with previous findings, delinquency history and moral disengagement were significant predictors of recent aggressive behavior. Furthermore, when ethnic/racial socialization was added to the model, promotion of mistrust provided additional predictive validity for aggressive behavior above and beyond the other factors assessed. Based on these findings, the inclusion of education on culture may prove to be an important supplement to established intervention tools for juvenile offenders. PMID:27453798
Ren, Zhengjia; Hood, Ralph W
2018-04-01
This study reports the development of an inventory to assess the perceived internalized homophobia of gay men in a collectivistic Chinese cultural context. The results of exploratory and confirmatory factor analyses using two samples suggested the viability and stability of a three-factor model: internalized heteronormativity (IHN), family-oriented identity (FOI), and socially oriented identity (SOI). The 11-item internalized homophobia inventory demonstrated good internal consistency and construct validity. Internalized homophobia was related positively to the extent of a sense of loneliness and negatively to self-evaluation and the discrepancy in self-identification as a gay man. In addition, the participants' internalized SOI consistently predicted their coming out choices in their social surroundings, while their FOI predicted their decisions to enter into heterosexual marriages. The findings suggest that sexual self-prejudice was correlated with IHN, family values, and social norms. The present research demonstrates that a culturally sensitive scale is necessary to understand the cultural and family-oriented values that influence gay Chinese men's everyday lives, self-constructs, and behavioral choices.
Pre-Service Teachers' Free and Structured Mathematical Problem Posing
ERIC Educational Resources Information Center
Silber, Steven; Cai, Jinfa
2017-01-01
This exploratory study examined how pre-service teachers (PSTs) pose mathematical problems for free and structured mathematical problem-posing conditions. It was hypothesized that PSTs would pose more complex mathematical problems under structured posing conditions, with increasing levels of complexity, than PSTs would pose under free posing…
Aspects of the Internal Structure of Nominalization: Roots, Morphology and Derivation
ERIC Educational Resources Information Center
Punske, Jeffrey
2012-01-01
This dissertation uses syntactic, semantic and morphological evidence from English nominalization to probe the interaction of event-structure and syntax, develop a typology of structural complexity within nominalization, and test hypotheses about the strict ordering of functional items. I focus on the widely assumed typology of nominalization…
Davis, Laurel; Hanson, Sheila K.; Zamir, Osnat; Gewirtz, Abigail H.; DeGarmo, David S.
2015-01-01
Deployment separation and reunifications are salient contexts that directly impact effective family functioning and parenting for military fathers. Yet, we know very little about determinants of post-deployed father involvement and effective parenting. The present study examined hypothesized risk and protective factors of observed parenting for 282 post-deployed fathers who served in the Army National Guard/Reserves. Pre-intervention data were employed from fathers participating in the After Deployment, Adaptive Parenting Tools (ADAPT) randomized control trial. Parenting practices were obtained from direct observation of father-child interaction and included measures of problem solving, harsh discipline, positive involvement, encouragement, and monitoring. Risk factors included combat exposure, negative life events, months deployed, and PTSD symptoms. Protective factors included education, income, dyadic adjustment, and social support. Results of a structural equation model predicting an effective parenting construct indicated that months deployed, income, and father age were most related to observed parenting, explaining 16% of the variance. We are aware of no other study utilizing direct parent-child observations of father’s parenting skills following overseas deployment. Implications for practice and preventive intervention are discussed. PMID:26213794
Correlated factors in amphibian decline: Exotic species and habitat change in western Washington
Adams, Michael J.
1999-01-01
Amphibian declines may frequently be associated with multiple, correlated factors. In western North America, exotic species and hydrological changes are often correlated and are considered 2 of the greatest threats to freshwater systems. Bullfrog (Rana catesbeiana) introductions are frequently cited as a threat to lentic-breeding anurans native to western North America and are a suspected factor in the decline of red-legged frogs (Rana aurora) in California. Introduced fish and habitat change are cited less frequently but are equally viable hypotheses. I examined the relation among introduced species, habitat, and the distribution and abundance of red-legged frogs in western Washington. Red-legged frog occurrence in the Puget Lowlands was more closely associated with habitat structure and the presence of exotic fish than with the presence of bull-frogs. The spread of exotics is correlated with a shift toward greater permanence in wetland habitats regionally. Conservation of more ephemeral wetland habitats may have direct benefits for some native amphibians and may also reduce the threat of exotic fish and bullfrogs, both of which were associated with permanent wetlands. Research and conservation efforts for lowland anurans in the West should emphasize the complexities of multiple contributing factors to amphibian losses.
Health Equity and Aging of Bisexual Older Adults: Pathways of Risk and Resilience
Shiu, Chengshi; Bryan, Amanda E. B.; Goldsen, Jayn; Kim, Hyun-Jun
2017-01-01
Abstract Objectives: Bisexual older adults are a growing yet largely invisible, underserved, and understudied population. Utilizing the Health Equity Promotion Model, we examined hypothesized mechanisms accounting for health disparities between bisexual older adults and lesbian and gay older adults. Method: Based on data from Caring and Aging with Pride, the largest national survey of LGBT older adults, this study (N = 2,463) utilized structural equation modeling to investigate direct and indirect associations between sexual identity (bisexual vs. lesbian and gay) and health via sexual identity factors (identity disclosure and internalized stigma), social resources, and socioeconomic status (SES). Results: Bisexual older adults reported significantly poorer health compared with lesbian and gay older adults. Indirect effects involving sexual identity factors, social resources, and SES explained the association between bisexual identity and poorer health. A potentially protective pathway was also identified wherein bisexuals had larger social networks after adjusting for other factors. Discussion: Bisexual older adults face distinct challenges and health risks relative to other older adults, likely because of the accumulation of socioeconomic and psychosocial disadvantages across the life course. Interventions taking into account older bisexuals’ unique risk and protective factors may be helpful in reducing health inequities. PMID:27815302
Risky sexual behaviour among unmarried young people in Cameroon: another look at family environment.
Dimbuene, Zacharie Tsala; Defo, Barthelemy Kuate
2011-03-01
Most studies of the association between family structure and risky sexual behaviour among adolescents and young adults have employed a risk perspective which assumes that, compared with other types, two-parent families are protective. Drawing from a positive-oriented approach in this study, it is hypothesized that within each family type some influential factors may mitigate such anticipated deleterious effects of non-intact families and decrease sexual risk-taking. The paper examines specifically the effects of risk and protective factors with an emphasis on family processes associated with resilience, using data from a pooled sample of 1025 females and males aged 12-24 years from Bandjoun (West Cameroon). Findings show that the quality of parent/guardian-youth relationships significantly decreases the odds of risky sexual behaviour by 36%, 65% and 50% in neither-, one- and two-parent families, respectively. For two-parent families only, parental control acts as a significant protective factor; it decreased by 41% the odds of risky sexual behaviour. Programmatically, protective family factors such as parent/guardian-youth interactions need to be promoted to improve the efficiency of reproductive health and HIV interventions in sub-Saharan Africa.
Huang, Tingting; Chang, Chin -Yuan; Lohman, Jeremy R.; ...
2016-10-01
Comparative analysis of the enediyne biosynthetic gene clusters revealed sets of conserved genes serving as outstanding candidates for the enediyne core. Here we report the crystal structures of SgcJ and its homologue NCS-Orf16, together with gene inactivation and site-directed mutagenesis studies, to gain insight into enediyne core biosynthesis. Gene inactivation in vivo establishes that SgcJ is required for C-1027 production in Streptomyces globisporus. SgcJ and NCS-Orf16 share a common structure with the nuclear transport factor 2-like superfamily of proteins, featuring a putative substrate binding or catalytic active site. Site-directed mutagenesis of the conserved residues lining this site allowed us tomore » propose that SgcJ and its homologues may play a catalytic role in transforming the linear polyene intermediate, along with other enediyne polyketide synthase-associated enzymes, into an enzyme-sequestered enediyne core intermediate. In conclusion, these findings will help formulate hypotheses and design experiments to ascertain the function of SgcJ and its homologues in nine-membered enediyne core biosynthesis.« less
Rocha, Juliana Monteiro de Almeida; Pinto, Míriam Plaza; Boubli, Jean Philippe; Grelle, Carlos Eduardo Viveiros
2015-01-01
The factors responsible for the formation of Amazonian primate communities are not well understood. Here we investigated the influence of interspecific competition in the assembly of these communities, specifically whether they follow an assembly rule known as "favored states". According to this rule, interspecific competition influences final species composition, resulting in functional groups that are equally represented in the community. We compiled presence-absence data for primate species at 39 Amazonian sites in Brazil, contrasting two regions with distinct productivity regimes: the eutrophic Juruá River basin and the oligotrophic Negro River basin. We tested two hypotheses: that interspecific competition is a mechanism that influences the structure of Amazonian primate communities, and that competition has had a greater influence on the structure of primate communities in regions with low productivity, where resources are more limited. We used null models to test the statistical significance of the results, and found a non-random pattern compatible with the favored states rule in the two regions. Our findings suggest that interspecific competition is an important force driving primate community assembly regardless of productivity regimes. PMID:26696089
[A Structural Equation Model of Pressure Ulcer Prevention Action in Clinical Nurses].
Lee, Sook Ja; Park, Ok Kyoung; Park, Mi Yeon
2016-08-01
The purpose of this study was to construct and test a structural equation model for pressure ulcer prevention action by clinical nurses. The Health Belief Model and the Theory of Planned Behavior were used as the basis for the study. A structured questionnaire was completed by 251 clinical nurses to analyze the relationships between concepts of perceived benefits, perceived barriers, attitude, subjective norm, perceived control, intention to perform action and behavior. SPSS 22.0 and AMOS 22.0 programs were used to analyze the efficiency of the hypothesized model and calculate the direct and indirect effects of factors affecting pressure ulcer prevention action among clinical nurses. The model fitness statistics of the hypothetical model fitted to the recommended levels. Attitude, subjective norm and perceived control on pressure ulcer prevention action explained 64.2% for intention to perform prevention action. The major findings of this study indicate that it is essential to recognize improvement in positive attitude for pressure ulcer prevention action and a need for systematic education programs to increase perceived control for prevention action.
Murray, Aja Louise; Eisner, Manuel; Ribeaud, Denis
2016-11-01
Recent studies have suggested that the structure of psychopathology may be usefully represented in terms of a general factor of psychopathology (p-factor) capturing variance common to a broad range of symptoms transcending diagnostic domains in addition to specific factors capturing variance common to smaller subsets of more closely related symptoms. Little is known about how the general co-morbidity captured by this p-factor develops and whether general co-morbidity increases or decreases over childhood and adolescence. We evaluated two competing hypotheses: 1) dynamic mutualism which predicts growth in general co-morbidity and associated p-factor strength over time and 2) p-differentiation which predicts that manifestations of liabilities towards psychopathology become increasingly specific over time. Data came from the Zurich Project on the Social Development of Children and Youths (z-proso), a longitudinal study of a normative sample (approx. 50 % male) measured at 8 time points from ages 7 to 15. We operationalised general co-morbidity as p-factor strength in a bi-factor model and used omega hierarchical to track how this changed over development. In contrast to the predictions of both dynamic mutualism and p-differentiation, p-factor strength remained relatively constant over the studied period suggesting that such processes do not govern the interplay between psychopathological symptoms during this phase of development. Future research should focus on earlier phases of development and on factors that maintain the consistency of symptom-general covariation across this period.
Factors affecting the remotely sensed response of coniferous forest plantations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Danson, F.M.; Curran, P.J.
1993-01-01
Remote sensing of forest biophysical properties has concentrated upon forest sites with a wide range of green vegetation amount and thereby leaf area index and canopy cover. However, coniferous forest plantations, an important forest type in Europe, are managed to maintain a large amount of green vegetation with little spatial variation. Therefore, the strength of the remotely sensed signal will, it is hypothesized, be determined more by the structure of this forest than by its cover. Airborne Thematic Mapper (ATM) and SPOT-1 HRV data were used to determine the effects of this structural variation on the remotely sensed response ofmore » a coniferous forest plantation in the United Kingdom. Red and near infrared radiance were strongly and negatively correlated with a range of structural properties and with the age of the stands but weakly correlated with canopy cover. A composite variable, related to the volume of the canopy, accounted for over 75% of the variation in near infrared radiance. A simple model that related forest structural variables to the remotely sensed response was used to understand and explain this response from a coniferous forest plantation.« less
Changes in assembly processes in soil bacterial communities following a wildfire disturbance.
Ferrenberg, Scott; O'Neill, Sean P; Knelman, Joseph E; Todd, Bryan; Duggan, Sam; Bradley, Daniel; Robinson, Taylor; Schmidt, Steven K; Townsend, Alan R; Williams, Mark W; Cleveland, Cory C; Melbourne, Brett A; Jiang, Lin; Nemergut, Diana R
2013-06-01
Although recent work has shown that both deterministic and stochastic processes are important in structuring microbial communities, the factors that affect the relative contributions of niche and neutral processes are poorly understood. The macrobiological literature indicates that ecological disturbances can influence assembly processes. Thus, we sampled bacterial communities at 4 and 16 weeks following a wildfire and used null deviation analysis to examine the role that time since disturbance has in community assembly. Fire dramatically altered bacterial community structure and diversity as well as soil chemistry for both time-points. Community structure shifted between 4 and 16 weeks for both burned and unburned communities. Community assembly in burned sites 4 weeks after fire was significantly more stochastic than in unburned sites. After 16 weeks, however, burned communities were significantly less stochastic than unburned communities. Thus, we propose a three-phase model featuring shifts in the relative importance of niche and neutral processes as a function of time since disturbance. Because neutral processes are characterized by a decoupling between environmental parameters and community structure, we hypothesize that a better understanding of community assembly may be important in determining where and when detailed studies of community composition are valuable for predicting ecosystem function.
Changes in assembly processes in soil bacterial communities following a wildfire disturbance
Ferrenberg, Scott; O'Neill, Sean P; Knelman, Joseph E; Todd, Bryan; Duggan, Sam; Bradley, Daniel; Robinson, Taylor; Schmidt, Steven K; Townsend, Alan R; Williams, Mark W; Cleveland, Cory C; Melbourne, Brett A; Jiang, Lin; Nemergut, Diana R
2013-01-01
Although recent work has shown that both deterministic and stochastic processes are important in structuring microbial communities, the factors that affect the relative contributions of niche and neutral processes are poorly understood. The macrobiological literature indicates that ecological disturbances can influence assembly processes. Thus, we sampled bacterial communities at 4 and 16 weeks following a wildfire and used null deviation analysis to examine the role that time since disturbance has in community assembly. Fire dramatically altered bacterial community structure and diversity as well as soil chemistry for both time-points. Community structure shifted between 4 and 16 weeks for both burned and unburned communities. Community assembly in burned sites 4 weeks after fire was significantly more stochastic than in unburned sites. After 16 weeks, however, burned communities were significantly less stochastic than unburned communities. Thus, we propose a three-phase model featuring shifts in the relative importance of niche and neutral processes as a function of time since disturbance. Because neutral processes are characterized by a decoupling between environmental parameters and community structure, we hypothesize that a better understanding of community assembly may be important in determining where and when detailed studies of community composition are valuable for predicting ecosystem function. PMID:23407312
Money Affects Theory of Mind Differently by Gender
Ridinger, Garret; McBride, Michael
2015-01-01
Theory of Mind (ToM) ─ the ability to understand other’s thoughts, intentions, and emotions ─ is important for navigating interpersonal relationships, avoiding conflict, and empathizing. Prior research has identified many factors that affect one’s ToM ability, but little work has examined how different kinds of monetary incentives affect ToM ability. We ask: Does money affect ToM ability? If so, how does the effect depend on the structure of monetary incentives? How do the differences depend on gender? We hypothesize that money will affect ToM ability differently by gender: monetary rewards increase males’ motivation to express ToM ability while simultaneously crowding out females’ motivation. This prediction is confirmed in an experiment that varies the structure of monetary rewards for correct answers in the Reading the Mind in the Eyes Test (RMET). RMET scores decrease for females and increase for males with individual payments, and this effect is stronger with competitively-structured payments. RMET scores do not significantly change when monetary earnings go to a charity. Whether money improves or hinders ToM ability, and, hence, success in social interactions, thus depends on the interaction of gender and monetary incentive structure. PMID:26633171
Money Affects Theory of Mind Differently by Gender.
Ridinger, Garret; McBride, Michael
2015-01-01
Theory of Mind (ToM)--the ability to understand other's thoughts, intentions, and emotions--is important for navigating interpersonal relationships, avoiding conflict, and empathizing. Prior research has identified many factors that affect one's ToM ability, but little work has examined how different kinds of monetary incentives affect ToM ability. We ask: Does money affect ToM ability? If so, how does the effect depend on the structure of monetary incentives? How do the differences depend on gender? We hypothesize that money will affect ToM ability differently by gender: monetary rewards increase males' motivation to express ToM ability while simultaneously crowding out females' motivation. This prediction is confirmed in an experiment that varies the structure of monetary rewards for correct answers in the Reading the Mind in the Eyes Test (RMET). RMET scores decrease for females and increase for males with individual payments, and this effect is stronger with competitively-structured payments. RMET scores do not significantly change when monetary earnings go to a charity. Whether money improves or hinders ToM ability, and, hence, success in social interactions, thus depends on the interaction of gender and monetary incentive structure.
Core-satellite species hypothesis and native versus exotic species in secondary succession
Martinez, Kelsey A.; Gibson, David J.; Middleton, Beth A.
2015-01-01
A number of hypotheses exist to explain species’ distributions in a landscape, but these hypotheses are not frequently utilized to explain the differences in native and exotic species distributions. The core-satellite species (CSS) hypothesis predicts species occupancy will be bimodally distributed, i.e., many species will be common and many species will be rare, but does not explicitly consider exotic species distributions. The parallel dynamics (PD) hypothesis predicts that regional occurrence patterns of exotic species will be similar to native species. Together, the CSS and PD hypotheses may increase our understanding of exotic species’ distribution relative to natives. We selected an old field undergoing secondary succession to study the CSS and PD hypotheses in conjunction with each other. The ratio of exotic to native species (richness and abundance) was observed through 17 years of secondary succession. We predicted species would be bimodally distributed and that exotic:native species ratios would remain steady or decrease through time under frequent disturbance. In contrast to the CSS and PD hypotheses, native species occupancies were not bimodally distributed at the site, but exotic species were. The exotic:native species ratios for both richness (E:Nrichness) and abundance (E:Ncover) generally decreased or remained constant throughout supporting the PD hypothesis. Our results suggest exotic species exhibit metapopulation structure in old field landscapes, but that metapopulation structures of native species are disrupted, perhaps because these species are dispersal limited in the fragmented landscape.
Effects of High Dietary HEME Iron and Radiation on Cardiovascular Function
NASA Technical Reports Server (NTRS)
Westby, Christian M.; Brown, A. K.; Platts, S. H.
2012-01-01
The radiation related health risks to astronauts is of particular concern to NASA. Data support that exposure to radiation is associated with a number of disorders including a heightened risk for cardiovascular diseases. Independent of radiation, altered nutrient status (e.g. high dietary iron) also increases ones risk for cardiovascular disease. However, it is unknown whether exposure to radiation in combination with high dietary iron further increases ones cardiovascular risk. The intent of our proposal is to generate compulsory data examining the combined effect of radiation exposure and iron overload on sensitivity to radiation injury to address HRP risks: 1) Risk Factor of Inadequate Nutrition; 2) Risk of Cardiac Rhythm Problems; and 3) Risk of Degenerative Tissue or other Health Effects from Space Radiation. Towards our goal we propose two distinct pilot studies using the following specific aims: Vascular Aim 1: To determine the short-term consequences of the independent and combined effects of exposure to gamma radiation and elevated body iron stores on measures of endothelial function and cell viability and integrity. We hypothesize that animals that have high body iron stores and are exposed to gamma radiation will show a greater reduction in endothelial dependent nitric oxid production and larger pathological changes in endothelial integrity than animals that have only 1 of those treatments (either high iron stores or exposure to gamma radiation). Vascular Aim 2: Identify and compare the effects of gamma radiation and elevated body iron stores on the genetic and epigenetic regulation of proteins associated with endothelial cell function. We hypothesize that modifications of epigenetic control and posttranslational expression of proteins associated with endothelial cell function will be differentially altered in rats with high body iron stores and exposed to gamma radiation compared to rats with only 1 type of treatment. Cardiac Aim 1: To determine the short-term consequences of the independent and combined effects of gamma radiation and elevated body iron stores on measures of cardiac structure. We hypothesize that modifications to cardiac structure and function will be greater in rats with high body iron stores and exposed to gamma radiation than in rats that have only 1 of those treatments. Cardiac Aim 2: Identify and compare the effects of gamma radiation and elevated body iron stores on the genetic and epigenetic regulation of proteins associated with cardiac structure and function. We hypothesize that modifications of epigenetic control and posttranslational expression of proteins associated with cardiac contractile function will be differentially altered in rats with high body iron stores and exposed to gamma radiation compared to rats with only 1 type of treatment.
Blood-Siegfried, Jane
2015-01-01
Sudden infant death syndrome (SIDS) is still not well understood. It is defined as the sudden and unexpected death of an infant without a definitive cause. There are numerous hypotheses about the etiology of SIDS but the exact cause or causes have never been pinpointed. Examination of theoretical pathologies might only be possible in animal models. Development of these models requires consideration of the environmental and/or developmental risk factors often associated with SIDS, as they need to explain how the risk factors could contribute to the cause of death. These models were initially developed in common laboratory animals to test various hypotheses to explain these infant deaths - guinea pig, piglet, mouse, neonatal rabbit, and neonatal rat. Currently, there are growing numbers of researchers using genetically altered animals to examine specific areas of interest. This review describes the different systems and models developed to examine the diverse hypotheses for the cause of SIDS and their potential for defining a causal mechanism or mechanisms.
Moon, Sung Seek; Rao, Uma
2011-01-01
In this article, we present the effects of three hypothesized protective factors: social activities, school-related activities, and anti-substance use media messages on adolescent tobacco and alcohol use. Data were drawn from the "Monitoring the Future" (MTF) research project, which was conducted by the Institute for Social Research at the University of Michigan. The sample included 2,551 twelfth-grade students. The results of the structural equation model showed that exposure to media anti-drug messages had an indirect negative effect on tobacco and alcohol use through school-related activity and social activity. The results suggest that comprehensive ecological interventions encompassing media, family, and school can increase on the preventive effects of adolescent's substance use.
Hernández-Díaz, Sonia; Levin, Michael
2014-01-01
Maternal use of anticonvulsants during the first trimester of pregnancy has been associated with an elevated risk of major congenital malformations in the offspring. Whether the increased risk is caused by the specific pharmacological mechanisms of certain anticonvulsants, the underlying epilepsy, or common genetic or environmental risk factors shared by epilepsy and malformations is controversial. We hypothesize that anticonvulsant therapies during pregnancy that attain more successful inhibition of neurotransmission might lead to both better seizure control in the mother and stronger alteration of bioelectrically-controlled processes in the embryo that result in structural malformations. If our theory were correct, development of pharmaceuticals that do not alter cell resting transmembrane voltage levels could result in safer drugs. PMID:24815983
Reducing structural uncertainty in conceptual hydrological modeling in the semi-arid Andes
NASA Astrophysics Data System (ADS)
Hublart, P.; Ruelland, D.; Dezetter, A.; Jourde, H.
2014-10-01
The use of lumped, conceptual models in hydrological impact studies requires placing more emphasis on the uncertainty arising from deficiencies and/or ambiguities in the model structure. This study provides an opportunity to combine a multiple-hypothesis framework with a multi-criteria assessment scheme to reduce structural uncertainty in the conceptual modeling of a meso-scale Andean catchment (1515 km2) over a 30 year period (1982-2011). The modeling process was decomposed into six model-building decisions related to the following aspects of the system behavior: snow accumulation and melt, runoff generation, redistribution and delay of water fluxes, and natural storage effects. Each of these decisions was provided with a set of alternative modeling options, resulting in a total of 72 competing model structures. These structures were calibrated using the concept of Pareto optimality with three criteria pertaining to streamflow simulations and one to the seasonal dynamics of snow processes. The results were analyzed in the four-dimensional space of performance measures using a fuzzy c-means clustering technique and a differential split sample test, leading to identify 14 equally acceptable model hypotheses. A filtering approach was then applied to these best-performing structures in order to minimize the overall uncertainty envelope while maximizing the number of enclosed observations. This led to retain 8 model hypotheses as a representation of the minimum structural uncertainty that could be obtained with this modeling framework. Future work to better consider model predictive uncertainty should include a proper assessment of parameter equifinality and data errors, as well as the testing of new or refined hypotheses to allow for the use of additional auxiliary observations.
Reducing structural uncertainty in conceptual hydrological modelling in the semi-arid Andes
NASA Astrophysics Data System (ADS)
Hublart, P.; Ruelland, D.; Dezetter, A.; Jourde, H.
2015-05-01
The use of lumped, conceptual models in hydrological impact studies requires placing more emphasis on the uncertainty arising from deficiencies and/or ambiguities in the model structure. This study provides an opportunity to combine a multiple-hypothesis framework with a multi-criteria assessment scheme to reduce structural uncertainty in the conceptual modelling of a mesoscale Andean catchment (1515 km2) over a 30-year period (1982-2011). The modelling process was decomposed into six model-building decisions related to the following aspects of the system behaviour: snow accumulation and melt, runoff generation, redistribution and delay of water fluxes, and natural storage effects. Each of these decisions was provided with a set of alternative modelling options, resulting in a total of 72 competing model structures. These structures were calibrated using the concept of Pareto optimality with three criteria pertaining to streamflow simulations and one to the seasonal dynamics of snow processes. The results were analyzed in the four-dimensional (4-D) space of performance measures using a fuzzy c-means clustering technique and a differential split sample test, leading to identify 14 equally acceptable model hypotheses. A filtering approach was then applied to these best-performing structures in order to minimize the overall uncertainty envelope while maximizing the number of enclosed observations. This led to retain eight model hypotheses as a representation of the minimum structural uncertainty that could be obtained with this modelling framework. Future work to better consider model predictive uncertainty should include a proper assessment of parameter equifinality and data errors, as well as the testing of new or refined hypotheses to allow for the use of additional auxiliary observations.
Moen, Vegard Pihl; Drageset, Jorunn; Eide, Geir Egil; Klokkerud, Mari; Gjesdal, Sturla
2017-02-01
The World Health Organization Disability Assessment Schedule (WHODAS) 2.0 is a generic instrument to assess disability covering six domains. The purpose of this study was to investigate the potential of the instrument for monitoring disability in specialized somatic rehabilitation by testing reliability, construct validity and responsiveness of WHODAS 2.0, Norwegian version, among patients with various health conditions. For taxonomy, terminology and definitions, the Consensus-based Standards for the Selection of Health Measurement Instruments were followed. Reproducibility was investigated by the intra-class correlation coefficient (ICC) in a randomly selected sample. Internal consistency was assessed by Cronbach's alpha. Construct validity was evaluated by correlations between WHODAS 2.0 and the Medical Outcomes Study 36-item Short Form, and fit of the hypothesized structure using confirmatory factor analysis (CFA). Responsiveness was evaluated in another randomly selected sample by testing a priori formulated hypotheses. Nine hundred seventy patients were included in the study. Reproducibility and responsiveness were evaluated in 53 and 104 patients, respectively. The ICC for the WHODAS 2.0 domains ranged from 0.63 to 0.84 and was 0.87 for total score. Cronbach's alpha for domains ranged from 0.75 to 0.94 and was 0.93 for total score. For construct validity, 6 of 12 expected correlations were confirmed and CFA did not achieve satisfactory fit indices. For responsiveness, 3 of 8 hypotheses were confirmed. The Norwegian version of WHODAS 2.0 showed moderate to satisfactory reliability and moderate validity in rehabilitation patients. However, the present study indicated possible limitations in terms of responsiveness.
Jantchou, Prévost; Monnet, Elisabeth; Carbonnel, Franck
2006-01-01
A rapid increase in the incidence of Crohn's disease and ulcerative colitis in developed countries, the occurrence of Crohn's disease in spouses, and a lack of complete concordance in monozygotic twins are strong arguments for the role of environmental factors in inflammatory bowel disease (IBD). Research in the field of environmental factors in IBD is based upon epidemiological (geographical and case-control), clinical and experimental studies. The role of two environmental factors has clearly been established in IBD. Smoking is a risk factor for Crohn's disease and a protective factor for ulcerative colitis; appendectomy is a protective factor for ulcerative colitis. Many other environmental factors for IBD have been investigated, including infectious agents, diet, drugs, stress and social status. They are detailed in the present review. Among them, atypical Mycobacteria, oral contraceptives and antibiotics could play a role in Crohn's disease. To date, three hypotheses associate environmental factors with the pathophysiology of IBD (loss of tolerance of intestinal immune system towards commensal bacterial flora): the hygiene, infection and cold chain hypotheses. Much work remains to be done to identify risk factors for IBD. Research identifying environmental factors that might cause a predisposition to IBD is useful. It may lead to disease prevention in subjects who are genetically predisposed and disease improvement in patients.
Social Networks in the Classroom: Personality Factors as Antecedents of Student Social Capital
ERIC Educational Resources Information Center
Seevers, Matthew T.; Johnson, Bryan R.; Darnold, Todd C.
2015-01-01
This study examines personality factors as antecedents of student social capital. We hypothesize relationships between two constructs taken from the five-factor model of personality (agreeableness and extraversion) and two variables that reflect a student's social capital (quantity of ties and strength of ties) in an academic setting. Analysis of…
ERIC Educational Resources Information Center
Fü rst, Guillaume; Ghisletta, Paolo; Lubart, Todd
2016-01-01
The present work proposes an integrative model of creativity that includes personality traits and cognitive processes. This model hypothesizes that three high-order personality factors predict two main process factors, which in turn predict intensity and achievement of creative activities. The personality factors are: "Plasticity" (high…
The Fundamental Skills Training Project
2003-08-01
rejecting hypotheses. This ITS teaches ecology concepts in areas including biomes , abiotic factors of plant growth, biotic factors in ecosystems, human...Deserts, Temperate Deciduous Forests, Coniferous Forests, Tropical Rainforests, Polar Regions, Tundra, Fresh Water, Marine . Abiotic Factors...critical points in each workspace. Incorporating motivational features that address individual characteristics such as learning styles and interests
Explaining Discrepancies in Arrest Rates between Black and White Male Juveniles
ERIC Educational Resources Information Center
Fite, Paula J.; Wynn, Porche'; Pardini, Dustin A.
2009-01-01
The authors investigated discrepancies in arrest rates between Black and White male juveniles by examining the role of early risk factors for arrest. Two hypotheses were evaluated: (a) Disproportionate minority arrest is due to increased exposure to early risk factors, and (b) a differential sensitivity to early risk factors contributes to…
ERIC Educational Resources Information Center
Johnson, Faye C. Stucy
1987-01-01
Tested hypotheses regarding importance of various factors on students' decision to enroll in a food service-related course. Findings include (1) interests and persons close to students were most influential and (2) teachers and students perceived similarly the order but not degree of importance of factors. (Author/CH)
Adolescent Psychosocial Risk Factors for Severe Intimate Partner Violence in Young Adulthood
ERIC Educational Resources Information Center
Keenan-Miller, Danielle; Hammen, Constance; Brennan, Patricia
2007-01-01
The authors examined prospective measures of psychosocial risk factors as predictors of severe intimate partner violence among a community sample of 610 young adults at risk for intergenerational transmission of depression. The hypothesized risk factors were youth history of depression by age 15 and maternal history of depression. Youth social…
Brown, Mark P
2006-01-01
The effect of nursing professionals (i.e., nurse aid/orderly, licensed practical nurse, registered nurse) pay structures and pay levels on hospitals risk-adjusted heart attack outcomes was determined. Operationalizing hospitals' heart attack outcomes as their thirty-day risk-adjusted mortality rates, a positive curvilinear relation is hypothesized between pay dispersion and hospitals' heart attack outcomes, whereas a direct relation is hypothesized between pay level and hospitals' heart attack outcomes. Pay level is also hypothesized as a moderator of the relation between pay dispersion and hospitals' heart attack outcomes. Using a sample of 138 California hospitals, support is not found for either the curvilinear relation between hospitals' nursing professionals pay dispersion and hospitals' heart attack outcomes, or the direct relation between nursing professionals' pay level and hospitals' heart attack outcomes. Support is found for the moderation hypothesis in which nursing professionals' pay level moderates the relation between hospitals' nursing professionals pay dispersion and hospitals' heart attack outcomes. Implications for practice are discussed in light of the study's results.
ERIC Educational Resources Information Center
Tanha, Marieh; Beck, Connie J. A.; Figueredo, Aurelio Jose; Raghavan, Chitra
2010-01-01
Research argues that coercive control (CC) is a special case of intimate partner violence (IPV). The present study hypothesized that instead CC is the "motivator" for other types of IPV, with control of the victim as the goal. When CC fails, physical types of IPV are used. This hypothesized relationship was tested using a large matched sample of…
Concepts for the development of light-weight composite structures for rotor burst containment
NASA Technical Reports Server (NTRS)
Holms, A. G.
1977-01-01
Published results on rotor burst containment with single materials, and on body armor using composite materials were used to establish a set of hypotheses about what variables might control the design of a weight-efficient protective device. Based on modern concepts for the design and analysis of small optimum seeking experiments, a particular experiment for evaluating the hypotheses and materials was designed. The design and methods for the analysis of results are described. The consequence of such hypotheses is that the device should consist of as many as four concentric rings, each to consist of a material uniquely chosen for its position in the penetration sequence.
Moses Lake Fishery Restoration Project : FY 1999 Annual Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None given
2000-12-01
The Moses Lake Project consists of 3 phases. Phase 1 is the assessment of all currently available physical and biological information, the collection of baseline biological data, the formulation of testable hypotheses, and the development of a detailed study plan to test the hypotheses. Phase 2 is dedicated to the implementation of the study plan including data collection, hypotheses testing, and the formulation of a management plan. Phase 3 of the project is the implementation of the management plan, monitoring and evaluation of the implemented recommendations. The project intends to restore the failed recreational fishery for panfish species (black crappie,more » bluegill and yellow perch) in Moses Lake as off site mitigation for lost recreational fishing opportunities for anadromous species in the upper Columbia River. This report summarizes the results of Phase 1 investigations and presents the study plan directed at initiating Phase 2 of the project. Phase 1of the project culminates with the formulation of testable hypotheses directed at investigating possible limiting factors to the production of panfish in Moses Lake. The limiting factors to be investigated will include water quality, habitat quantity and quality, food limitations, competition, recruitment, predation, over harvest, environmental requirements, and the physical and chemical limitations of the system in relation to the fishes.« less
Schield, Drew R; Adams, Richard H; Card, Daren C; Corbin, Andrew B; Jezkova, Tereza; Hales, Nicole R; Meik, Jesse M; Perry, Blair W; Spencer, Carol L; Smith, Lydia L; García, Gustavo Campillo; Bouzid, Nassima M; Strickland, Jason L; Parkinson, Christopher L; Borja, Miguel; Castañeda-Gaytán, Gamaliel; Bryson, Robert W; Flores-Villela, Oscar A; Mackessy, Stephen P; Castoe, Todd A
2018-06-15
The Mojave rattlesnake (Crotalus scutulatus) inhabits deserts and arid grasslands of the western United States and Mexico. Despite considerable interest in its highly toxic venom and the recognition of two subspecies, no molecular studies have characterized range-wide genetic diversity and population structure or tested species limits within C. scutulatus. We used mitochondrial DNA and thousands of nuclear loci from double-digest restriction site associated DNA sequencing to infer population genetic structure throughout the range of C. scutulatus, and to evaluate divergence times and gene flow between populations. We find strong support for several divergent mitochondrial and nuclear clades of C. scutulatus, including splits coincident with two major phylogeographic barriers: the Continental Divide and the elevational increase associated with the Central Mexican Plateau. We apply Bayesian clustering, phylogenetic inference, and coalescent-based species delimitation to our nuclear genetic data to test hypotheses of population structure. We also performed demographic analyses to test hypotheses relating to population divergence and gene flow. Collectively, our results support the existence of four distinct lineages within C. scutulatus, and genetically defined populations do not correspond with currently recognized subspecies ranges. Finally, we use approximate Bayesian computation to test hypotheses of divergence among multiple rattlesnake species groups distributed across the Continental Divide, and find evidence for co-divergence at this boundary during the mid-Pleistocene. Copyright © 2018 Elsevier Inc. All rights reserved.
Mitochondria: A Connecting Link In The Major Depressive Disorder Jigsaw.
Sharma, Shilpa; Akundi, Ravi Shankar
2018-03-02
Depression is a widespread phenomenon with varying degrees of pathology in different patients. Various hypotheses have been proposed for the cause and continuance of depression. Some of these include, but not limited to, the monoamine hypothesis, the neuroendocrine hypothesis, and the more recent epigenetic and inflammatory hypotheses. In this article, we review all the above hypotheses with a focus on the role of mitochondria as the connecting link. Oxidative stress, respiratory activity, mitochondrial dynamics and metabolism are some of the mitochondria-dependent factors which are affected during depression. We also propose exogenous ATP as a contributing factor to depression. Literature review shows that pro-inflammatory markers are elevated in depressive individuals. The cause for elevated levels of cytokines in depression is not completely understood. We propose exogenous ATP activates purinergic receptors which in turn increase the levels of various pro-inflammatory factors in the pathophysiology of depression. Mitochondria are integral to the function of neurons and undergo dysfunction in major depressive disorder patients. This dysfunction is reflected in all the various hypotheses that have been proposed for depression. Among the newer targets identified, which also involve mitochondria, includes the role of exogenous ATP. The diversity of purinergic receptors, and their differential expression among various individuals in the population, due to genetic and environmental (prenatal) influences, may influence the susceptibility and severity of depression. Identifying specific receptors involved and using patient-specific purinergic receptor antagonist may be an appropriate therapeutic course in the future. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Smith, Brian N; Wang, Joyce M; Vaughn-Coaxum, Rachel A; Di Leone, Brooke A L; Vogt, Dawne
2017-01-01
The postdeployment social context is likely highly salient in explaining mental health symptoms following deployment. The aim of this study was to examine the role of postdeployment social factors (social support and social reintegration difficulty) in linking deployment-related experiences (warfare exposure, sexual harassment, concerns about relationship disruptions, and deployment social support) and posttraumatic stress disorder (PTSD) symptomatology in male and female veterans. A survey was administered to 998 potential participants (after accounting for undeliverable mail) who had returned from deployment to Afghanistan or Iraq. Completed surveys were received from 469 veterans, yielding a response rate of 47%. Hypotheses were examined using structural equation modeling. For male and female veterans, deployment factors predicted later PTSD symptoms through postdeployment social support and social reintegration, with lower support and higher social reintegration difficulty both associated with higher PTSD symptomatology. While the final models for women and men indicated similar risk mechanisms, some differences in pathways were observed. Sexual harassment presented more of a risk for women, whereas lower social support was a greater risk factor for men. Postdeployment social factors appear to represent potentially important targets for interventions aiming to reduce the potential impact of stressful deployment experiences.
Mohammed, Selma F; Borlaug, Barry A; Roger, Véronique L; Mirzoyev, Sultan A; Rodeheffer, Richard J; Chirinos, Julio A; Redfield, Margaret M
2012-11-01
Patients with heart failure and preserved ejection fraction (HFpEF) display increased adiposity and multiple comorbidities, factors that in themselves may influence cardiovascular structure and function. This has sparked debate as to whether HFpEF represents a distinct disease or an amalgamation of comorbidities. We hypothesized that fundamental cardiovascular structural and functional alterations are characteristic of HFpEF, even after accounting for body size and comorbidities. Comorbidity-adjusted cardiovascular structural and functional parameters scaled to independently generated and age-appropriate allometric powers were compared in community-based cohorts of HFpEF patients (n=386) and age/sex-matched healthy n=193 and hypertensive, n=386 controls. Within HFpEF patients, body size and concomitant comorbidity-adjusted cardiovascular structural and functional parameters and survival were compared in those with and without individual comorbidities. Among HFpEF patients, comorbidities (obesity, anemia, diabetes mellitus, and renal dysfunction) were each associated with unique clinical, structural, functional, and prognostic profiles. However, after accounting for age, sex, body size, and comorbidities, greater concentric hypertrophy, atrial enlargement and systolic, diastolic, and vascular dysfunction were consistently observed in HFpEF compared with age/sex-matched normotensive and hypertensive. Comorbidities influence ventricular-vascular properties and outcomes in HFpEF, yet fundamental disease-specific changes in cardiovascular structure and function underlie this disorder. These data support the search for mechanistically targeted therapies in this disease.
NASA Technical Reports Server (NTRS)
Klinger, L. F.
1988-01-01
The study of mass extinction events has largely focused on defining an environmental factor or factors that might account for specific patterns of faunal demise. Several hypotheses elaborate on how a given environmental factor might affect fauna directly, but differentially, causing extinction in certain taxa but not others. Yet few studies have considered specific habitat changes that might result from natural vegetation processes or from perturbations of vegetation. The role of large-scale habitat change induced by natural successional change from forest to bog (paludification) is examined and how large perturbations (e.g., volcanism, bolide impacts) might favor increased rates of paludification and consequent mass extinctions is considered. This hypothesis has an advantage over other hypotheses for mass extinctions in that modern day analogs of paludification are common throughout the world, thus allowing for considerable testing.
Moses, Tally
2015-05-01
Better understanding of the individual and environmental factors that promote adolescents' use of more or less adaptive coping strategies with mental illness stigma would inform interventions designed to bolster youth resilience. This cross-sectional study draws on data from research on adolescents' well-being after discharge from a first psychiatric hospitalization to explore the relationships between anticipated coping in reaction to a hypothetical social stigma scenario, and various factors conceptualized as 'coping resource' and 'coping vulnerability' factors. Focusing on coping strategies also identified in the companion article, we hypothesize that primary and secondary control engagement coping would relate to more coping resource and less coping vulnerability factors, and the opposite would be true for disengagement, aggression/confrontation and efforts to disconfirm stereotypes. Data were elicited from interviews with 102 adolescents within 7 days of discharge. Hypothesized coping resource factors included social resources, optimistic illness perceptions, better hospital experiences and higher self-esteem. Vulnerability factors included more previous stigma experiences, desire for concealment of treatment, more contingent self-worth, higher symptom levels and higher anticipated stress. Multivariate ordinary least squares (OLS) regression was used to analyze associations between coping strategy endorsement and correlates. Although some coping correlates 'behaved' contrary to expectations, for the most part, our hypotheses were confirmed. As expected, youth anticipating reacting to the stigmatizing situation with greater disengagement, aggression/confrontation or efforts to disconfirm stenotypes rated significantly lower on 'coping resources' such as self-esteem and higher on vulnerability factors such as symptom severity. The opposite was true for youth who anticipated exercising more primary and secondary control engagement coping. This study begins to identify factors that promote more and less adaptive coping strategies among youth at high risk for social stigma. Some factors that can be modified in the shorter term point to useful directions for clinical interventions. © The Author(s) 2014.
Shim, Eun-Jung; Hahm, Bong-Jin; Go, Dong Jin; Lee, Kwang-Min; Noh, Hae Lim; Park, Seung-Hee; Song, Yeong Wook
2018-06-01
To examine factors in the fear-avoidance model, such as pain, pain catastrophizing, fear-avoidance beliefs, physical disability, and depression and their relationships with physical and psychological quality of life in patients with rheumatic diseases. The data were obtained from 360 patients with rheumatic diseases who completed self-report measures assessing study variables. Structural equation modeling was used to examine the hypothesized relationships among factors specified in the fear-avoidance model predicting physical and psychological quality of life. Final models fit the data well, explaining 96% and 82% of the variance in physical and psychological quality of life, respectively. Higher pain catastrophizing was related to stronger fear-avoidance beliefs that had a direct negative association with physical disability and depression, which, in turn, negatively affected physical quality of life. Pain severity was also directly related to physical disability. Physical disability also affected physical quality of life indirectly through depression. The hypothesized relationships specified in the model were also confirmed for psychological quality of life. However, physical disability had an indirect association with psychological quality of life via depression. The current results underscore the significant role of cognitive, affective, and behavioral factors in perceived physical disability and their mediated detrimental effect on physical and psychological quality of life in patients with rheumatic diseases. Implications for rehabilitation The fear-avoidance model is applicable to the prediction of quality of life in patients with rheumatic diseases. As pain-catastrophizing and fear-avoidance beliefs are important factors linked to physical disability and depression, intervening these cognitive factors is necessary to improve physical function and depression in patients with rheumatic diseases. Considering the strong association between depression and physical and psychological quality of life, the assessment and treatment of the former should be included in the rehabilitation of patients with rheumatic diseases. Interventions targeting physical function and depression are likely to be effective in terms of improving physical and psychological quality of life in patients with rheumatic diseases.
Initiation of coagulation by tissue factor (TF) is a potentially powerful regulator of local inflammatory responses. We hypothesized that blockade of TF-factor VIIa (FVIIa) complex would decrease lung inflammation and proinflammatory cytokine release after tracheal instillation o...
Corn Response to Competition: Growth Alteration vs. Yield Limiting Factors
USDA-ARS?s Scientific Manuscript database
Understanding competition mechanisms among adjacent plants can improve site-specific management recommendations. This 2-yr study compared two hypotheses, yield limiting factors vs. behavior modification, to explain plant interactions. Corn was grown under different levels of stress by varying light ...
Jeffries, William L; Greene, Kevin M; Paz-Bailey, Gabriela; McCree, Donna Hubbard; Scales, Lamont; Dunville, Richard; Whitmore, Suzanne
2018-04-09
This study sought to determine why young men who have sex with men (MSM) have higher HIV incidence rates than older MSM in the United States. We developed hypotheses that may explain this disparity. Data came from peer-reviewed studies published during 1996-2016. We compared young and older MSM with respect to behavioral, clinical, psychosocial, and structural factors that promote HIV vulnerability. Compared with older MSM, young MSM were more likely to have HIV-discordant condomless receptive intercourse. Young MSM also were more likely to have "any" sexually transmitted infection and gonorrhea. Among HIV-positive MSM, young MSM were less likely to be virally suppressed, use antiretroviral therapy, and be aware of their infection. Moreover, young MSM were more likely than older MSM to experience depression, polysubstance use, low income, decreased health care access, and early ages of sexual expression. These factors likely converge to exacerbate age-associated HIV incidence disparities among MSM.
Curtiss, Joshua; McLaughlin, Katie A.; Nolen-Hoeksema, Susan
2016-01-01
Social anxiety and depression are common mental health problems among adolescents and are frequently comorbid. Primary aims of this study were to (1) elucidate the nature of individual differences in specific emotion regulation deficits among adolescents with symptoms of social anxiety and depression, and (2) determine whether repetitive negative thinking (RNT) functions as a transdiagnostic factor. A diverse sample of adolescents (N = 1065) completed measures assessing emotion regulation and symptoms of social anxiety and depression. Results indicated that adolescents with high levels of social anxiety and depression symptoms reported decreased emotional awareness, dysregulated emotion expression, and reduced use of emotion management strategies. The hypothesized structural model in which RNT functions as a transdiagnostic factor exhibited a better fit than an alternative model in which worry and rumination function as separate predictors of symptomatology. Findings implicate emotion regulation deficits and RNT in the developmental psychopathology of youth anxiety and mood disorders. PMID:28579659
Sierra-Fitzgerald, O; Quevedo-Caicedo, J
The aim of this article is to relate two theories regarding the structure of the human mind. We suggest that the theory of multiple intelligences, a neurocognitive theory of the psychologist Howard Garnerd provides a suitable context for theoretical understanding and validation of the hypothesis of the pathology of superiority, a neuropsychological hypothesis formulated by the neuropsychologists Norman Geschwind and Albert Galaburda. Similarly, we show that, apart from being a context, the first theory enriches the second. We review the essential elements of both theories together with the arguments for them so that the reader may judge for himself. Similarly we review the factors determining intelligence; the association between neuropathology and intellectual dysfunction, general and specific, and the new directions in the understanding of human cognition. We propose to consider the first theory as a fertile ambit and broad methodological framework for investigation in neuropsychology. This simultaneously shows the relevance of including neuropsychological investigation in broader cognitive and neuropsychological theories and models.
Suicide risk factors for young adults: testing a model across ethnicities.
Gutierrez, P M; Rodriguez, P J; Garcia, P
2001-06-01
A general path model based on existing suicide risk research was developed to test factors contributing to current suicidal ideation in young adults. A sample of 673 undergraduate students completed a packet of questionnaires containing the Beck Depression Inventory, Adult Suicidal Ideation Questionnaire, and Multi-Attitude Suicide Tendency Scale. They also provided information on history of suicidality and exposure to attempted and completed suicide in others. Structural equation modeling was used to test the fit of the data to the hypothesized model. Goodness-of-fit indices were adequate and supported the interactive effects of exposure, repulsion by life, depression, and history of self-harm on current ideation. Model fit for three subgroups based on race/ethnicity (i.e., White, Black, and Hispanic) determined that repulsion by life and depression function differently across groups. Implications of these findings for current methods of suicide risk assessment and future research are discussed in the context of the importance of culture.
Why still marry? The role of feelings in the persistence of marriage as an institution(1).
Billari, Francesco C; Liefbroer, Aart C
2016-09-01
Despite cohabitation becoming increasingly equivalent to marriage in some of the most 'advanced' Western European societies, the vast majority of people still marry. Why so? Existing theories, mostly based on various approaches tied to cognitive decision-making, do not provide a sufficient explanation of the persistence of marriage. In this article, we argue that feelings attached to marriage, i.e. the affective evaluation of those involved in a partner relationship concerning marriage as opposed to cohabitation, explain the persistent importance of marriage as an institution. We argue that socialization, biological and social-structural factors affect these affective evaluations. We provide a test of our hypotheses using a longitudinal study of young adults in the Netherlands. The results of our analyses are consistent with a central role of feelings in the decision to marry, as well as with a role for key moderating factors such as gender. © London School of Economics and Political Science 2016.
Effects of Living Alone on Social Capital and Health Among Older Adults in China.
Xu, Qingwen; Norstrand, Julie A; Du, Yan
2015-12-01
Social capital has been connected with positive health outcomes across countries, including China. Given the rise in the number of seniors living alone, there is a need to examine the health benefits of social capital, accounting for living arrangements. Data from the 2005 Chinese General Social Survey were used to test research hypotheses. Controlling for demographics, elders living alone possessed similar level of social capital compared with elders living with others. While bonding and linking social capital were significant factors in urban areas and linking social capital was a significant factor in rural areas, the relationship between living alone and health did not differ based on the level of social capital possession. When the traditional intergenerational living arrangement has not been a valid option for many older adults in China, seeking new way of family caring, and developing appropriate social and institutional structures to assist elders living alone, becomes critical. © The Author(s) 2016.
Koshy, Anson J.; Watkins, Marley W.; Cassano, Michael C.; Wahlberg, Andrea C.; Mautone, Jennifer A.; Blum, Nathan J.
2013-01-01
Objective To evaluate the construct validity of the Behavioral Health Checklist (BHCL) for children aged from 4 to 12 years from diverse backgrounds. Method The parents of 4–12-year-old children completed the BHCL in urban and suburban primary care practices affiliated with a tertiary-care children’s hospital. Across practices, 1,702 were eligible and 1,406 (82.6%) provided consent. Children of participating parents were primarily non-Hispanic black/African American and white/Caucasian from low- to middle-income groups. Confirmatory factor analyses examined model fit for the total sample and subsamples defined by demographic characteristics. Results The findings supported the hypothesized 3-factor structure: Internalizing Problems, Externalizing Problems, and Inattention/Hyperactivity. The model demonstrated adequate to good fit across age-groups, gender, races, income groups, and suburban versus urban practices. Conclusion The findings provide strong evidence of the construct validity, developmental appropriateness, and cultural sensitivity of the BHCL when used for screening in primary care. PMID:23978505
Hurtz, Gregory M; Williams, Kevin J
2009-05-01
This study investigated factors influencing ongoing participation in employee development activities. A multiple-indicator structural equation model building on the theory of planned behavior and prior employee development literature was tested with a survey across 4 organizations on 2 occasions. The model uses reactions to past participation and past supportiveness of the social and organizational environment as indirect antecedents of participation, filtered through their impact on attitudes and behavioral intentions toward future participation. Learning goal orientation also influenced attitudes toward participation. Whereas personal control over participation and higher levels of voluntariness were negatively related to participation, intentions to participate and availability of opportunities arose as strong predictors of higher participation rates. Many significant hypothesized paths were found, and 85% of the variance in participation was explained by the model variables. Increasing employee awareness of opportunities and managing positive attitudes toward those opportunities are recommended as key factors for increasing participation rates. (c) 2009 APA, all rights reserved.
Balducci, Cristian; Fraccaroli, Franco; Schaufeli, Wilmar B
2011-10-01
Workplace bullying refers to prolonged exposure to frequent hostile behaviors at work, which can lead to severe stress reactions. Research in this area has not revealed a clear picture on how bullying escalates in organizations. Drawing on recent developments in work stress theory, this study tested a comprehensive model of bullying in which work environmental and personality factors were hypothesized to act as antecedents of bullying and post-traumatic stress symptoms as an outcome. Structural equation modeling on data provided by 609 public sector employees in Italy showed that job demands (workload and role conflict) and job resources (decision authority, co-worker support and salary/promotion prospects) were related to bullying over and above neuroticism, and that bullying mediated the relationship between job demands and PTSD symptoms. Evidence also emerged for a buffering effect of job resources on the job demands-bullying relationship. Overall results are compatible with a view of bullying as a strain phenomenon, initiated by both work environmental and personality factors.
Players' perceptions of accountability factors in secondary school sports settings.
Hastie, P A
1993-06-01
The purpose of this study was to gauge the extent to which students believed that the accountability strategies employed by their coaches had significant effects on their involvement in sports training sessions. Questionnaire data from 235 secondary school athletes were analyzed using linear structural relations to test a model of accountability hypothesized as operating in these coaching settings. The accountability strategy of active instruction was found to be a variable that significantly affected the students' valuing of their coaches as well as their task involvement. However, the rewards/consequences variable was not found to be a predictor of valuing or task involvement, suggesting that these athletes seemed more task oriented than reliant on external sanctions. The results of this study can only be generalized to team sport settings. Detailed examination needs to be made of the processes through which accountability factors operate for other contexts, including individual sports and competitive levels. Further research could also be undertaken into gender differences, especially in relation to the gender of coaches.
Park, Yujeong; Seo, Dong Gi; Park, Jaekook; Bettini, Elizabeth; Smith, Jamie
2016-01-01
This study aims to explore the influences of personal, vocational, and job environment related factors that are associated with job satisfaction of individuals with disabilities in South Korea. Data for wage-based working employees from a nationwide survey were obtained, which resulted in a total number of 417 participants. The six hypotheses and mediation effects of personal and work related environmental factors were tested using the structural equation modeling drawn from existing research evidence. Results revealed that (a) life satisfaction and job related environments directly influenced job satisfaction; (b) the relationship between personal experience and job satisfaction was mediated by life satisfaction for both mild/moderate and severe/profound disabilities group; and (c) the mediating role of job environment between vocational preparedness and job satisfaction was only observed for individuals with mild/moderate disabilities. Summary of findings and implications for future research and practices are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.
Albiero, Paolo; Matricardi, Giada; Speltri, Daniela; Toso, Diana
2009-04-01
The present study examined the validity of the Basic Empathy Scale (BES) [Jolliffe, D., & Farrington, D. P. (2006a). Development and validation of the Basic Empathy Scale. Journal of Adolescence, 29, 589-611; Jolliffe, D., & Farrington, D. P. (2006b). Examining the relationship between low empathy and bullying. Aggressive Behavior, 32(6), 540-550.] and found further evidence for the scale's good psychometric properties. The BES was administered to a sample of 655 Italian adolescents to examine the generalizability and reliability of its factor structure. The results of the confirmatory factor analysis showed a reasonable data fit with the two hypothesized BES domains of Cognitive Empathy and Affective Empathy. Scale reliability was also satisfactory, showing good internal consistency. Lastly, BES scores were significantly associated with other empathy questionnaire scores (the Interpersonal Reactivity Index and Balanced Emotional Empathy Scale) and with a scale measuring prosocial behavior. Research and practice implications are discussed.
Intergenerational transmission of depression: a launch and grow model of change across adolescence.
Garber, Judy; Cole, David A
2010-11-01
The present study tested a "launch-and-grow" type of cascade model in which an earlier risk factor (e.g., exposure to maternal depression by age 12) was hypothesized to predict several risk processes during development (e.g., stress, family relationships, self-worth [SW]), which then set the course for the growth of children's depressive symptoms over time. Participants were 240 mothers and children (mean age = 11.87 years, SD = 0.57) who were evaluated annually across 6 years. The Structured Clinical Interview for DSM diagnoses was used to assess mothers' psychiatric history; 185 mothers had had a mood disorder and 55 mothers were lifetime free of psychiatric diagnoses. At each assessment, mothers completed measures of their current level of depressive symptoms and stressful life events; adolescents completed measures about their perceptions of the family environment and their SW; and clinicians rated adolescents' level of depressive symptoms based on separate interviews with the adolescent and mother. Latent growth curve analyses revealed that history of maternal depression significantly predicted the intercepts of the growth trajectories of adolescents' depressive symptoms, mothers' current depressive symptoms, stressful life events, family environment, and adolescents' SW. The intercepts of each of these variables then predicted the trajectory (i.e., slope) of the growth of adolescents' depressive symptoms across the 6 years of the study. These results were consistent with the hypothesized model of maternal depression launching a set of risk factors, which in turn predict the growth of depressive symptoms during adolescence. Implications for interventions aimed at preventing depression in at-risk youth are discussed.
Psychometric evaluation of the Differentiation of Self Inventory for adolescents.
Knauth, Donna G; Skowron, Elizabeth A
2004-01-01
Evidence of psychometric support is needed for use of the Differentiation of Self Inventory with adolescents as a clinical assessment instrument to evaluate psychotherapeutic progress and outcomes, and for its use as a research instrument to evaluate the effectiveness of interventions on the basis of Bowen family systems theory. To examine the reliability and validity of the 46-item, self-report Differentiation of Self Inventory (DSI) for use with adolescents. An ex post facto research design was used to determine the psychometric properties of the DSI for adolescents, and to test theoretically grounded hypotheses drawn from Bowen theory that linked differentiation of self with chronic anxiety and symptom development. The DSI, the State-Trait Anxiety Inventory, and the Symptom Pattern Scale were administered to an ethnically diverse sample of 363 adolescents 14 to 19 years of age. The DSI full scale demonstrated good internal consistency reliability, with a Cronbach's alpha coefficient of.84. Factor analysis yielded a six-factor structure, representing the multidimensionality of the DSI items among adolescents. As hypothesized, differentiation of self mediated the relation between chronic anxiety and symptom development (p <.001), indicating that greater differentiation of self predicted fewer symptoms over and above chronic anxiety, and lending support to the construct validity of the DSI in adolescent populations. The results of this study support the use of the DSI with adolescents. Future longitudinal studies are needed for definitive causal conclusions regarding the role that differentiation of self plays as a mediator between the relation of chronic anxiety and symptom development.
Oshri, Assaf; Kogan, Steven; Liu, Sihong; Sweet, Lawrence; Mackillop, James
2017-12-01
African American men experience increases in smoking during the young adult transition. Exposure to childhood adversity, a risk factor which disproportionately affects African American men, has been identified as a robust precursor to health risk behavior in general and cigarette smoking in particular. The intermediate mechanisms that transmit the influence of early adversity to smoking behavior are not well understood. We tested a model of the escalation of smoking behaviors among young adult African American men, investigating sleep disturbance and delayed reward discounting as intermediate factors linking adverse childhood experiences with smoking. Hypotheses were tested with three waves of data (M age-T1 = 20.34, M age-T2 = 21.92, M age-T3 = 23.02) from 505 African American men living in rural counties in South Georgia. Men provided self-report data on their adverse childhood experiences, sleep problems, and smoking behavior using audio-assisted computer self-interviews. Men also completed a computer-based delayed reward discounting task. Structural equation modeling analyses supported our hypotheses: Adverse childhood experiences predicted poor sleep adequacy, which forecast increases in delayed reward discounting; discounting, in turn, predicted increased smoking. Significant indirect pathways were detected linking adversity to discounting via sleep adequacy and linking sleep adequacy to smoking via discounting. Prevention and intervention researchers can draw on these findings to develop programs that focus on sleep adequacy to reduce smoking in African American men exposed to childhood adversity.