Comparison of an Ultrasonic Phased Array Evaluation with Destructive Analysis of a Documented Leak Path in a Nozzle Removed from Service

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

Cinson, Anthony D.; Crawford, Susan L.; MacFarlan, Paul J.

2012-09-24

Non-destructive and destructive testing methods were employed to evaluate a documented boric acid leakage path through an Alloy 600 control rod drive mechanism (CRDM) penetration from the North Anna Unit 2 reactor pressure vessel head that was removed from service in 2002. A previous ultrasonic in-service-inspection (ISI) conducted by industry prior to the head removal, identified a probable leakage path in Nozzle 63 located in the interference fit between the penetration tube and the vessel head. In this current examination, Nozzle 63 was examined using phased array (PA) ultrasonic testing with a 5.0-MHz, eight-element annular array; immersion data were acquiredmore » from the nozzle inner diameter (ID) surface. A variety of focal laws were employed to evaluate the signal responses from the interference fit region. These responses were compared to responses obtained from a mockup specimen that was used to determine detection limits and characterization capabilities for wastage and boric acid presence in the interference fit region. Nozzle 63 was destructively examined after the completion of the ultrasonic nondestructive evaluation (NDE) to visually assess the leak paths. These destructive and nondestructive results compared favorably« less

Modeling the Impact of Social Discrimination and Financial Hardship on the Sexual Risk of HIV Among Latino and Black Men Who Have Sex With Men

PubMed Central

Bingham, Trista; Kim, Junyeop; Wheeler, Darrell P.; Millett, Gregorio A.

2012-01-01

Objectives. We examined the impact of social discrimination and financial hardship on unprotected anal intercourse with a male sex partner of serodiscordant or unknown HIV status in the past 3 months among 1081 Latino and 1154 Black men who have sex with men (MSM; n = 2235) residing in Los Angeles County, California; New York, New York; and Philadelphia, Pennsylvania. Methods. We administered HIV testing and a questionnaire assessing 6 explanatory variables. We combined traditional mediation analysis with the results of a path analysis to simultaneously examine the direct, indirect, and total effects of these variables on the outcome variable. Results. Bivariate analysis showed that homophobia, racism, financial hardship, and lack of social support were associated with unprotected anal intercourse with a serodiscordant or sero-unknown partner. Path analysis determined that these relations were mediated by participation in risky sexual situations and lack of social support. However, paths between the explanatory variable and 2 mediating variables varied by participants’ serostatus. Conclusions. Future prevention research and program designs should specifically address the differential impact of social discrimination and financial hardship on lack of social support and risky sexual situations among Latino and Black MSM. PMID:22401516

A Comparison of Various MRA Methods Applied to Longitudinal Evaluation Studies in Vocational Education.

ERIC Educational Resources Information Center

Kapes, Jerome T.; And Others

Three models of multiple regression analysis (MRA): single equation, commonality analysis, and path analysis, were applied to longitudinal data from the Pennsylvania Vocational Development Study. Variables influencing weekly income of vocational education students one year after high school graduation were examined: grade point averages (grades…

Path analysis of the genetic integration of traits in the sand cricket: a novel use of BLUPs.

PubMed

Roff, D A; Fairbairn, D J

2011-09-01

This study combines path analysis with quantitative genetics to analyse a key life history trade-off in the cricket, Gryllus firmus. We develop a path model connecting five traits associated with the trade-off between flight capability and reproduction and test this model using phenotypic data and estimates of breeding values (best linear unbiased predictors) from a half-sibling experiment. Strong support by both types of data validates our causal model and indicates concordance between the phenotypic and genetic expression of the trade-off. Comparisons of the trade-off between sexes and wing morphs reveal that these discrete phenotypes are not genetically independent and that the evolutionary trajectories of the two wing morphs are more tightly constrained to covary than those of the two sexes. Our results illustrate the benefits of combining a quantitative genetic analysis, which examines statistical correlations between traits, with a path model that focuses upon the causal components of variation. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

Insights into vehicle trajectories at the handling limits: analysing open data from race car drivers

NASA Astrophysics Data System (ADS)

Kegelman, John C.; Harbott, Lene K.; Gerdes, J. Christian

2017-02-01

Race car drivers can offer insights into vehicle control during extreme manoeuvres; however, little data from race teams is publicly available for analysis. The Revs Program at Stanford has built a collection of vehicle dynamics data acquired from vintage race cars during live racing events with the intent of making this database publicly available for future analysis. This paper discusses the data acquisition, post-processing, and storage methods used to generate the database. An analysis of available data quantifies the repeatability of professional race car driver performance by examining the statistical dispersion of their driven paths. Certain map features, such as sections with high path curvature, consistently corresponded to local minima in path dispersion, quantifying the qualitative concept that drivers anchor their racing lines at specific locations around the track. A case study explores how two professional drivers employ distinct driving styles to achieve similar lap times, supporting the idea that driving at the limits allows a family of solutions in terms of paths and speed that can be adapted based on specific spatial, temporal, or other constraints and objectives.

The impact of environmental factors on cycling speed on shared paths.

PubMed

Boufous, Soufiane; Hatfield, Julie; Grzebieta, Raphael

2018-01-01

Despite the importance of cycling speed on shared paths to the amenity and safety of users, few studies have systematically measured it, nor examined circumstances surrounding it. Speed was measured for 5421 riders who were observed cycling on shared paths across 12 metropolitan and regional locations in Sydney, Australia. Multivariate regression analysis was carried out to examine rider and environmental factors that contribute to riders cycling above the median speed. The study found that observed riders travelled at a median speed of 16km/h (mean 18.4km/h). Nearly 80% of riders travelled at 20km/h or less and 7.8% at speeds of more than 30km/h. Riders were significantly less likely to cycle above the median speed on shared paths that had an average volume of over 20 pedestrians/hour. Riders were significantly more likely to travel above the median speed on paths that had a centreline (OR: 1.71, 95% CI: 1.41-2.07), on wider paths (over 3.5m) (OR: 1.34, 95% CI: 1.12-1.59) and on paths with visual segregation between cyclists and pedestrians. Visual segregation, where cycling and walking areas are differentiated by the type of material or by paint colour used, was the strongest predictor of travelling above median speed on shared paths (OR: 3.9, 95% CI: 3.1-4.8). The findings suggest that riders adjust their speeds to accommodate pedestrians and path conditions. Path characteristics that support separation from pedestrians may allow relatively higher speeds, and associated amenity, without substantial loss of safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

Examining the Relationships among Coaching Staff Diversity, Perceptions of Diversity, Value Congruence, and Life Satisfaction

ERIC Educational Resources Information Center

Cunningham, George B.

2009-01-01

The purpose of this study was to examine relationships among coaching staff diversity, perceptions of diversity, value congruence, and life satisfaction. Data were collected from 71 coaching staffs (N = 196 coaches). Observed path analysis was used to examine the study predictions. Results indicate that actual staff diversity was positively…

Life stress and atherosclerosis: a pathway through unhealthy lifestyle.

PubMed

Mainous, Arch G; Everett, Charles J; Diaz, Vanessa A; Player, Marty S; Gebregziabher, Mulugeta; Smith, Daniel W

2010-01-01

To examine the relationship between a general measure of chronic life stress and atherosclerosis among middle aged adults without clinical cardiovascular disease via pathways through unhealthy lifestyle characteristics. We conducted an analysis of The Multi-Ethnic Study of Atherosclerosis (MESA). The MESA collected in 2000 includes 5,773 participants, aged 45-84. We computed standard regression techniques to examine the relationship between life stress and atherosclerosis as well as path analysis with hypothesized paths from stress to atherosclerosis through unhealthy lifestyle. Our outcome was sub-clinical atherosclerosis measured as presence of coronary artery calcification (CAC). A logistic regression adjusted for potential confounding variables along with the unhealthy lifestyle characteristics of smoking, excessive alcohol use, high caloric intake, sedentary lifestyle, and obesity yielded no significant relationship between chronic life stress (OR 0.93, 95% CI 0.80-1.08) and CAC. However, significant indirect pathways between chronic life stress and CAC through smoking (p = .007), and sedentary lifestyle (p = .03) and caloric intake (.002) through obesity were found. These results suggest that life stress is related to atherosclerosis once paths of unhealthy coping behaviors are considered.

Self-Concept and Academic Achievement: A Meta-Analysis of Longitudinal Relations

ERIC Educational Resources Information Center

Huang, Chiungjung

2011-01-01

The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from 0.20 to 0.27 between prior self-concept and subsequent academic…

Cytological Evaluation and REBA HPV-ID HPV Testing of Newly Developed Liquid-Based Cytology, EASYPREP: Comparison with SurePath.

PubMed

Lee, Youn Soo; Gong, Gyungyub; Sohn, Jin Hee; Ryu, Ki Sung; Lee, Jung Hun; Khang, Shin Kwang; Cho, Kyung-Ja; Kim, Yong-Man; Kang, Chang Suk

2013-06-01

The objective of this study was to evaluate a newly-developed EASYPREP liquid-based cytology method in cervicovaginal specimens and compare it with SurePath. Cervicovaginal specimens were prospectively collected from 1,000 patients with EASYPREP and SurePath. The specimens were first collected by brushing for SurePath and second for EASYPREP. The specimens of both methods were diagnosed according to the Bethesda System. Additionally, we performed to REBA HPV-ID genotyping and sequencing analysis for human papillomavirus (HPV) on 249 specimens. EASYPREP and SurePath showed even distribution of cells and were equal in cellularity and staining quality. The diagnostic agreement between the two methods was 96.5%. Based on the standard of SurePath, the sensitivity, specificity, positive predictive value, and negative predictive value of EASYPREP were 90.7%, 99.2%, 94.8%, and 98.5%, respectively. The positivity of REBA HPV-ID was 49.4% and 95.1% in normal and abnormal cytological samples, respectively. The result of REBA HPV-ID had high concordance with sequencing analysis. EASYPREP provided comparable results to SurePath in the diagnosis and staining quality of cytology examinations and in HPV testing with REBA HPV-ID. EASYPREP could be another LBC method choice for the cervicovaginal specimens. Additionally, REBA HPV-ID may be a useful method for HPV genotyping.

Structural model of self‐care agency in patients with diabetes: A path analysis of the Instrument of Diabetes Self‐Care Agency and body self‐awareness

PubMed Central

Shimizu, Yasuko; Uchiumi, Kyoko; Asou, Kawai; Kuroda, Kumiko; Murakado, Naoko; Seto, Natsuko; Masaki, Harue; Ishii, Hidetoki

2016-01-01

Aim The aim of this study was to examine a causal model of self‐care agency by exploring the relationship between the structure of “body self‐awareness” and the structure of the Instrument of Diabetes Self‐Care Agency (IDSCA). Methods The participants were 353 patients with diabetes. The internal consistency of the six items for body self‐awareness was examined by calculating the factor structure using principal factor analysis and Cronbach's alpha. In order to examine the relationship between the seven factors in the IDSCA, a path analysis was conducted. Results With regard to the factor structure, the factor loading of these five items was 0.511–0.743 (α = 0.739). In the path analysis, “body self‐awareness” was influenced by the “ability to acquire knowledge” and had a direct effect (0.33) on the “motivation to self‐manage”, while “motivation to self‐manage” had an effect (−0.32) on the “ability to self‐manage”. The Goodness‐of‐Fit Index was 0.974. Conclusion “Body self‐awareness” plays a part in the self‐care operation process and serves as an intermediary factor to enable the performance of self‐care operations by making the most use of self‐care agency. Moreover, striking a proper balance between self‐management that is focused on the treatment of diabetes and a person's ability for self‐management of diabetes was found to be important. PMID:27224894

Verification of relationship model between Korean new elderly class's recovery resilience and productive aging.

PubMed

Cho, Gun-Sang; Kim, Dae-Sung; Yi, Eun-Surk

2015-12-01

The purpose of this study is to verification of relationship model between Korean new elderly class's recovery resilience and productive aging. As of 2013, this study sampled preliminary elderly people in Gyeonggi-do and other provinces nationwide. Data from a total of effective 484 subjects was analyzed. The collected data was processed using the IBM SPSS 20.0 and AMOS 20.0, and underwent descriptive statistical analysis, confirmatory factor analysis, and structure model verification. The path coefficient associated with model fitness was examined. The standardization path coefficient between recovery resilience and productive aging is β=0.975 (t=14.790), revealing a statistically significant positive effect. Thus, it was found that the proposed basic model on the direct path of recovery resilience and productive aging was fit for the model.

Verification of relationship model between Korean new elderly class’s recovery resilience and productive aging

PubMed Central

Cho, Gun-Sang; Kim, Dae-Sung; Yi, Eun-Surk

2015-01-01

The purpose of this study is to verification of relationship model between Korean new elderly class’s recovery resilience and productive aging. As of 2013, this study sampled preliminary elderly people in Gyeonggi-do and other provinces nationwide. Data from a total of effective 484 subjects was analyzed. The collected data was processed using the IBM SPSS 20.0 and AMOS 20.0, and underwent descriptive statistical analysis, confirmatory factor analysis, and structure model verification. The path coefficient associated with model fitness was examined. The standardization path coefficient between recovery resilience and productive aging is β=0.975 (t=14.790), revealing a statistically significant positive effect. Thus, it was found that the proposed basic model on the direct path of recovery resilience and productive aging was fit for the model. PMID:26730383

Mortality, migration, income, and air pollution: a comparative study

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

Bozzo, S.R.; Novak, K.M.; Galdos, F.

1978-06-02

The interrelationships among different demographic factors, specific causes of death, median family income, and estimated air pollution emissions were examined. Using the Medical Data Base (MEDABA) developed at Brookhaven National Laboratory, the entire population of the United States was cross-tabulated by income and emission levels of air pollutants. Path analysis was used to examine a number of patterns and relationships for each age, race, and sex group containing a minimum of 10,000 persons. Competitive and complementary effects were observed. These effects were frequently age dependent and occasionaly sex related. This specialized data base, the application of path analysis, and themore » development of a dynamic population and mortality model, in combination, proved to be a useful tool for investigating the effects of energy related pollutants on the exposed population.« less

Family Functioning and Adolescent Alcohol Use: A Moderated Mediation Analysis

PubMed Central

Ohannessian, Christine McCauley; Flannery, Kaitlin M.; Simpson, Emily; Russell, Beth S.

2016-01-01

The primary goals of this longitudinal study were to examine the relationship between family functioning and adolescent alcohol use and to examine whether depressed mood mediates this relationship. An additional goal was to explore whether these relations were moderated by gender. The sample included 1,031 high school students from the Mid-Atlantic United States. Participants completed surveys in school during the spring of 2007, 2008, and 2009. Path analysis results indicated that family functioning predicted alcohol use for girls. Moreover, depressed mood mediated this relationship. None of the direct paths between family functioning and adolescent alcohol use were significant for boys. However, similar to girls, depressed mood negatively predicted alcohol use for boys. Taken together, the findings highlight the need for prevention programs targeting adolescent substance use to consider gender-specific trajectories. PMID:26994346

Relationships between the quality of blended learning experience, self-regulated learning, and academic achievement of medical students: a path analysis.

PubMed

Kassab, Salah Eldin; Al-Shafei, Ahmad I; Salem, Abdel Halim; Otoom, Sameer

2015-01-01

This study examined the relationships between the different aspects of students' course experience, self-regulated learning, and academic achievement of medical students in a blended learning curriculum. Perceptions of medical students (n=171) from the Royal College of Surgeons in Ireland, Medical University of Bahrain (RCSI Bahrain), on the blended learning experience were measured using the Student Course Experience Questionnaire (SCEQ), with an added e-Learning scale. In addition, self-regulated learning was measured using the Motivated Strategies for Learning Questionnaire (MSLQ). Academic achievement was measured by the scores of the students at the end of the course. A path analysis was created to test the relationships between the different study variables. Path analysis indicated that the perceived quality of the face-to-face component of the blended experience directly affected the motivation of students. The SCEQ scale "quality of teaching" directly affected two aspects of motivation: control of learning and intrinsic goal orientation. Furthermore, appropriate course workload directly affected the self-efficacy of students. Moreover, the e-Learning scale directly affected students' peer learning and critical thinking but indirectly affected metacognitive regulation. The resource management regulation strategies, time and study environment, and effort regulation directly affected students' examination scores (17% of the variance explained). However, there were no significant direct relationships between the SCEQ scales and cognitive learning strategies or examination scores. The results of this study will have important implications for designing blended learning courses in medical schools.

The role of critical ethnic awareness and social support in the discrimination-depression relationship among Asian Americans: path analysis.

PubMed

Kim, Isok

2014-01-01

This study used a path analytic technique to examine associations among critical ethnic awareness, racial discrimination, social support, and depressive symptoms. Using a convenience sample from online survey of Asian American adults (N = 405), the study tested 2 main hypotheses: First, based on the empowerment theory, critical ethnic awareness would be positively associated with racial discrimination experience; and second, based on the social support deterioration model, social support would partially mediate the relationship between racial discrimination and depressive symptoms. The result of the path analysis model showed that the proposed path model was a good fit based on global fit indices, χ²(2) = 4.70, p = .10; root mean square error of approximation = 0.06; comparative fit index = 0.97; Tucker-Lewis index = 0.92; and standardized root mean square residual = 0.03. The examinations of study hypotheses demonstrated that critical ethnic awareness was directly associated (b = .11, p < .05) with the racial discrimination experience, whereas social support had a significant indirect effect (b = .48; bias-corrected 95% confidence interval [0.02, 1.26]) between the racial discrimination experience and depressive symptoms. The proposed path model illustrated that both critical ethnic awareness and social support are important mechanisms for explaining the relationship between racial discrimination and depressive symptoms among this sample of Asian Americans. This study highlights the usefulness of the critical ethnic awareness concept as a way to better understand how Asian Americans might perceive and recognize racial discrimination experiences in relation to its mental health consequences.

Analysis of Academic Administrators' Attitudes: Annual Evaluations and Factors That Improve Teaching

ERIC Educational Resources Information Center

Cherry, Brian D.; Grasse, Nathan; Kapla, Dale; Hamel, Brad

2017-01-01

This article examines academic administrators' attitudes towards the academic evaluation process in the US and those factors that are utilised to improve teaching. We use path regressions to examine satisfaction with evaluation procedures, as well as the direct and indirect effects of these factors on perceptions of whether the evaluation process…

Analysis of Factors Influencing Creative Personality of Elementary School Students

ERIC Educational Resources Information Center

Park, Jongman; Kim, Minkee; Jang, Shinho

2017-01-01

This quantitative research examined factors that affect elementary students' creativity and how those factors correlate. Aiming to identify significant factors that affect creativity and to clarify the relationship between these factors by path analysis, this research was designed to be a stepping stone for creativity enhancement studies. Data…

GLOBAL ALTERNATIVE FUTURE SCENARIOS

EPA Science Inventory

One way to examine possible future outcomes for environmental protection is through the development and analysis of alternative future scenarios. This type of assessment postulates two or more different paths that social and environmental development might take, using correspond...

The prediction of postpartum depression: The role of the PRECEDE model and health locus of control

PubMed Central

Moshki, Mahdi; Kharazmi, Akram; Cheravi, Khadijeh; Beydokhti, Tahereh Baloochi

2015-01-01

Background: The main purpose of this study was to investigate the effect of the PRECEDE model and health locus of control (HLC) on postpartum depression. This study used the path analysis to test the pattern of causal relations through the correlation coefficients. Materials and Method: The participants included 230 pregnant women in the north-east of Iran who were selected by convenience sampling. To analyze data, Pearson correlation and path analysis were applied to examine the relationships between variables using SPSS 20 and LISREL 8.50software. Results: The result of path analysis showed that a positive correlation exists between predisposing (knowledge, internal HLC, powerful others HLC, chance HLC) enabling and reinforcing factors with postpartum depression by GHQ score (GFI = 1, RSMEA = 000). Conclusion: The current study supported the application of the PRECEDE model and HLC in understanding the promoting behaviors in mental health and demonstrated their relationships with postpartum depression. PMID:26288792

Inter-rater reliability of PATH observations for assessment of ergonomic risk factors in hospital work.

PubMed

Park, Jung-Keun; Boyer, Jon; Tessler, Jamie; Casey, Jeffrey; Schemm, Linda; Gore, Rebecca; Punnett, Laura

2009-07-01

This study examined the inter-rater reliability of expert observations of ergonomic risk factors by four analysts. Ten jobs were observed at a hospital using a newly expanded version of the PATH method (Buchholz et al. 1996), to which selected upper extremity exposures had been added. Two of the four raters simultaneously observed each worker onsite for a total of 443 observation pairs containing 18 categorical exposure items each. For most exposure items, kappa coefficients were 0.4 or higher. For some items, agreement was higher both for the jobs with less rapid hand activity and for the analysts with a higher level of ergonomic job analysis experience. These upper extremity exposures could be characterised reliably with real-time observation, given adequate experience and training of the observers. The revised version of PATH is applicable to the analysis of jobs where upper extremity musculoskeletal strain is of concern.

Path Analysis Examining Self-Efficacy and Decision-Making Performance on a Simulated Baseball Task

ERIC Educational Resources Information Center

Hepler, Teri J.; Feltz, Deborah L.

2012-01-01

The purpose of this study was to examine the relationship between decision-making self-efficacy and decision-making performance in sport. Undergraduate students (N = 78) performed 10 trials of a decision-making task in baseball. Self-efficacy was measured before performing each trial. Decision-making performance was assessed by decision speed and…

Hard paths, soft paths or no paths? Cross-cultural perceptions of water solutions

NASA Astrophysics Data System (ADS)

Wutich, A.; White, A. C.; Roberts, C. M.; White, D. D.; Larson, K. L.; Brewis, A.

2013-06-01

In this study, we examine how development status and water scarcity shape people's perceptions of "hard path" and "soft path" water solutions. Based on ethnographic research conducted in four semi-rural/peri-urban sites (in Bolivia, Fiji, New Zealand, and the US), we use content analysis to conduct statistical and thematic comparisons of interview data. Our results indicate clear differences based on development status and, to a lesser extent, water scarcity. People in less developed sites were more likely to suggest hard path solutions, less likely to suggest soft path solutions, and more likely to see no path to solutions than people in more developed sites. Thematically, people in less developed sites envisioned solutions that involve small-scale water infrastructure and decentralized, community based solutions, while people in more developed sites envisioned solutions that involve large-scale infrastructure and centralized, regulatory water solutions. People in water-scarce sites were less likely to suggest soft path solutions and more likely to see no path to solutions (but no more likely to suggest hard path solutions) than people in water-rich sites. Thematically, people in water-rich sites seemed to perceive a wider array of unrealized potential soft path solutions than those in water-scarce sites. On balance, our findings are encouraging in that they indicate that people are receptive to soft path solutions in a range of sites, even those with limited financial or water resources. Our research points to the need for more studies that investigate the social feasibility of soft path water solutions, particularly in sites with significant financial and natural resource constraints.

Different Paths from Powerlessness to Empowerment: A Dramatistic Analysis of Two Eating Disorder Therapies.

ERIC Educational Resources Information Center

Cooks, Leda; Descutner, David

1993-01-01

Uses a dramatistic analysis to examine the rhetorical elements of two therapeutic discourses designed to help women cope with eating disorders: spiritual recovery therapy (SR) and feminist psychoanalytic therapy (FT). Finds each therapy has the same key terms but serve different functions and encourage different interpretations. (NH)

Relationships between the quality of blended learning experience, self-regulated learning, and academic achievement of medical students: a path analysis

PubMed Central

Kassab, Salah Eldin; Al-Shafei, Ahmad I; Salem, Abdel Halim; Otoom, Sameer

2015-01-01

Purpose This study examined the relationships between the different aspects of students’ course experience, self-regulated learning, and academic achievement of medical students in a blended learning curriculum. Methods Perceptions of medical students (n=171) from the Royal College of Surgeons in Ireland, Medical University of Bahrain (RCSI Bahrain), on the blended learning experience were measured using the Student Course Experience Questionnaire (SCEQ), with an added e-Learning scale. In addition, self-regulated learning was measured using the Motivated Strategies for Learning Questionnaire (MSLQ). Academic achievement was measured by the scores of the students at the end of the course. A path analysis was created to test the relationships between the different study variables. Results Path analysis indicated that the perceived quality of the face-to-face component of the blended experience directly affected the motivation of students. The SCEQ scale “quality of teaching” directly affected two aspects of motivation: control of learning and intrinsic goal orientation. Furthermore, appropriate course workload directly affected the self-efficacy of students. Moreover, the e-Learning scale directly affected students’ peer learning and critical thinking but indirectly affected metacognitive regulation. The resource management regulation strategies, time and study environment, and effort regulation directly affected students’ examination scores (17% of the variance explained). However, there were no significant direct relationships between the SCEQ scales and cognitive learning strategies or examination scores. Conclusion The results of this study will have important implications for designing blended learning courses in medical schools. PMID:25610011

Examination of Bidirectional Relationships between Parent Stress and Two Types of Problem Behavior in Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Zaidman-Zait, Anat; Mirenda, Pat; Duku, Eric; Szatmari, Peter; Georgiades, Stelios; Volden, Joanne; Zwaigenbaum, Lonnie; Vaillancourt, Tracy; Bryson, Susan; Smith, Isabel; Fombonne, Eric; Roberts, Wendy; Waddell, Charlotte; Thompson, Ann

2014-01-01

Path analysis within a structural equation modeling framework was employed to examine the relationships between two types of parent stress and children's externalizing and internalizing behaviors over a 4-year period, in a sample of 184 mothers of young children with autism spectrum disorder. Parent stress was measured with the Parenting Stress…

An Examination of Reflective Thinking, Learning Approaches, and Self-Efficacy Beliefs at the University of the South Pacific: A Path Analysis Approach

ERIC Educational Resources Information Center

Phan, Huy P.

2007-01-01

This study examined the causal and mediating relations between students' learning approaches, self-efficacy beliefs, stages of reflective thinking, and academic performance. Second-year undergraduate students (n = 241; 118 females, 123 males) in the South Pacific were administered the revised version of Biggs' Study Process Questionnaire, the…

An Examination of Preservice Teachers' Intentions to Pursue Careers in Special Education

ERIC Educational Resources Information Center

Zhang, Dake; Wang, Qiu; Losinski, Mickey; Katsiyannis, Antonis

2014-01-01

An understanding of one's intention to pursue a career related to special education is crucial yet there is limited research in this area. This study examined factors that influence teacher candidates' intention to pursue a career in special education by surveying 214 preservice teachers. Data were analyzed using path analysis to capture…

A potential conflict between preserving regional plant diversity and biotic resistance to an invasive grass, Microstegium vimineum

Treesearch

J. Stephen Brewer

2010-01-01

The relevance of diversity-biotic resistance studies to conservation of biodiversity could be improved by simultaneously examining the drivers of regional diversity and their effects on local species diversity and invasion. Using path analysis, I examined direct and indirect effects of various abiotic factors (i.e., flooding, treefall gaps, soil texture, proximity to...

Application of non-attenuating frequency radars for prediction of rain attenuation and space diversity performance

NASA Technical Reports Server (NTRS)

Goldhirsh, J.

1979-01-01

In order to establish transmitter power and receiver sensitivity levels at frequencies above 10 GHz, the designers of earth-satellite telecommunication systems are interested in cumulative rain fade statistics at variable path orientations, elevation angles, climatological regions, and frequencies. They are also interested in establishing optimum space diversity performance parameters. In this work are examined the many elements involved in the employment of single non-attenuating frequency radars for arriving at the desired information. The elements examined include radar techniques and requirements, phenomenological assumptions, path attenation formulations and procedures, as well as error budgeting and calibration analysis. Included are the pertinent results of previous investigators who have used radar for rain attenuation modeling. Suggestions are made for improving present methods.

Hard paths, soft paths or no paths? Cross-cultural perceptions of water solutions

NASA Astrophysics Data System (ADS)

Wutich, A.; White, A. C.; White, D. D.; Larson, K. L.; Brewis, A.; Roberts, C.

2014-01-01

In this study, we examine how development status and water scarcity shape people's perceptions of "hard path" and "soft path" water solutions. Based on ethnographic research conducted in four semi-rural/peri-urban sites (in Bolivia, Fiji, New Zealand, and the US), we use content analysis to conduct statistical and thematic comparisons of interview data. Our results indicate clear differences associated with development status and, to a lesser extent, water scarcity. People in the two less developed sites were more likely to suggest hard path solutions, less likely to suggest soft path solutions, and more likely to see no path to solutions than people in the more developed sites. Thematically, people in the two less developed sites envisioned solutions that involve small-scale water infrastructure and decentralized, community-based solutions, while people in the more developed sites envisioned solutions that involve large-scale infrastructure and centralized, regulatory water solutions. People in the two water-scarce sites were less likely to suggest soft path solutions and more likely to see no path to solutions (but no more likely to suggest hard path solutions) than people in the water-rich sites. Thematically, people in the two water-rich sites seemed to perceive a wider array of unrealized potential soft path solutions than those in the water-scarce sites. On balance, our findings are encouraging in that they indicate that people are receptive to soft path solutions in a range of sites, even those with limited financial or water resources. Our research points to the need for more studies that investigate the social feasibility of soft path water solutions, particularly in sites with significant financial and natural resource constraints.

Analysis of the Relation of Teachers' Organizational Identification and Organizational Communication

ERIC Educational Resources Information Center

Yildiz, Kaya

2013-01-01

In this study the relationship between the organizational identification and organizational communication of primary school teachers is examined through path analysis. The study group in the study is formed by (n = 362) primary school teachers working at primary schools located in the center of Bolu in the 2011-2012 academic year. In the study,…

Cryogenic Fluid Management Technology Development for Nuclear Thermal Propulsion

NASA Technical Reports Server (NTRS)

Taylor, B. D.; Caffrey, J.; Hedayat, A.; Stephens, J.; Polsgrove, R.

2015-01-01

Cryogenic fluid management technology is critical to the success of future nuclear thermal propulsion powered vehicles and long duration missions. This paper discusses current capabilities in key technologies and their development path. The thermal environment, complicated from the radiation escaping a reactor of a nuclear thermal propulsion system, is examined and analysis presented. The technology development path required for maintaining cryogenic propellants in this environment is reviewed. This paper is intended to encourage and bring attention to the cryogenic fluid management technologies needed to enable nuclear thermal propulsion powered deep space missions.

Socialization of Culture and Coping with Discrimination Among American Indian Families: Examining Cultural Correlates of Youth Outcomes

PubMed Central

Yasui, Miwa; Dishion, Thomas J.; Stormshak, Elizabeth; Ball, Alison

2016-01-01

Objective The current study examines the interrelations between observed parental cultural socialization and socialization of coping with discrimination, and youth outcomes among a sample of 92 American Indian adolescents and their parents in a rural reservation. Method Path analysis is used to examine the relationships among observed parental socialization (cultural socialization and socialization of coping with discrimination), and youth-reported perceived discrimination, ethnic identity and depression. Results Findings reveal that higher levels of observed parental cultural socialization and socialization of coping with discrimination predict lower levels of depression as reported by youth 1 year later. Path analyses also show that observed parental cultural socialization and socialization of coping with discrimination are positively associated with youth ethnic identity. Conclusions These findings point to the importance of integrating familial socialization of culture and coping with discrimination in fostering resilience among American Indian youth. PMID:28503256

[Association between Emotional Labor, Emotional Dissonance, Burnout and Turnover Intention in Clinical Nurses: A Multiple-Group Path Analysis across Job Satisfaction].

PubMed

Back, Chi Yun; Hyun, Dae Sung; Chang, Sei Jin

2017-12-01

This study was conducted to investigate the influence of emotional labor, emotional dissonance, and burnout on nurse's turnover intention and examine the effect of job satisfaction on the relationships among emotional labor, emotional dissonance, burnout, and turnover intention. The sample consisted of 350 nurses recruited from 6 general hospitals in 2 cities in Korea. A multiple-group analysis was utilized. Data were analyzed using SPSS statistics 23 and AMOS 20. In the path analysis, turnover intention was directly related to burnout in clinical nurses who had a high job satisfaction (β=.24, p=.003), while it was indirectly related to emotional dissonance (β=.13, p=.002). In the multiple-group path analysis, turnover intention was directly related to emotional dissonance (β=.18, p=.033) and burnout (β=.26, p=.002) for nurses with low job satisfaction. These results indicate that manuals and guidelines to alleviate the negative effects of emotional labor, emotional dissonance, and burnout, and to increase job satisfaction are strongly required to reduce turnover intention in nurses at the organizational level as well as at the individual level. © 2017 Korean Society of Nursing Science

Morphological awareness and reading comprehension: Examining mediating factors.

PubMed

Levesque, Kyle C; Kieffer, Michael J; Deacon, S Hélène

2017-08-01

The relation between morphological awareness-defined as the awareness of and ability to manipulate the smallest units of meaning in language-and reading comprehension remains in need of specification. In this study, we evaluated four potential intervening variables through which morphological awareness may contribute indirectly to reading comprehension. We assessed word reading and vocabulary as well as children's ability to read and analyze the meaning of morphologically complex words (morphological decoding and morphological analysis, respectively). Controls of phonological awareness and nonverbal ability were included in the model. Participants were 221 English-speaking children in Grade 3. Multivariate path analyses revealed evidence of two indirect relations and one direct relation between morphological awareness and reading comprehension. In the first indirect path, morphological awareness contributed to morphological decoding, which then influenced word reading and finally reading comprehension. In a second indirect path, morphological awareness contributed to morphological analysis, which contributed to reading comprehension. Finally, in a direct path, morphological awareness contributed to reading comprehension beyond all other variables. These findings inform as to the potential mechanisms underlying the relation between morphological awareness and reading comprehension in children. Copyright © 2017 Elsevier Inc. All rights reserved.

The Path through Graduate School: A Longitudinal Examination 10 Years after Bachelor's Degree. Postsecondary Education Descriptive Analysis Report. NCES 2007-162

ERIC Educational Resources Information Center

Nevill, Stephanie C.; Chen, Xianglei

2007-01-01

The report uses longitudinal data from the 1992-93 Baccalaureate and Beyond Study (B&B:93/03) to examine the characteristics related to graduate degree enrollment, persistence, and completion among 1992-93 bachelor's degree recipients. About 40 percent of 1992-93 bachelor's degree recipients had enrolled in a graduate degree program by 2003.…

Considering New Paths for Success: An Examination of the Research and Methods on Urban School-University Partnerships Post-No Child Left Behind

ERIC Educational Resources Information Center

Flynn, Joseph E.; Hunt, Rebecca D.; Johnson, Laura Ruth; Wickman, Scott A.

2014-01-01

This article examines urban school-university partnership research after No Child Left Behind. Central to the review is an analysis in the trend of research methods utilized across studies. It was found that many studies are single-case studies or anecdotal. There are few quantitative, sustained qualitative, or mixed-methods studies represented in…

The Relationship between Experiences of Discrimination and Mental Health among Lesbians and Gay Men: An Examination of Internalized Homonegativity and Rejection Sensitivity as Potential Mechanisms

ERIC Educational Resources Information Center

Feinstein, Brian A.; Goldfried, Marvin R.; Davila, Joanne

2012-01-01

Objective: The current study used path analysis to examine potential mechanisms through which experiences of discrimination influence depressive and social anxiety symptoms. Method: The sample included 218 lesbians and 249 gay men (total N = 467) who participated in an online survey about minority stress and mental health. The proposed model…

Examining the design features of a communication-rich, problem-centred mathematics professional development

NASA Astrophysics Data System (ADS)

de Araujo, Zandra; Orrill, Chandra Hawley; Jacobson, Erik

2018-04-01

While there is considerable scholarship describing principles for effective professional development, there have been few attempts to examine these principles in practice. In this paper, we identify and examine the particular design features of a mathematics professional development experience provided for middle grades teachers over 14 weeks. The professional development was grounded in a set of mathematical tasks that each had one right answer, but multiple solution paths. The facilitator engaged participants in problem solving and encouraged participants to work collaboratively to explore different solution paths. Through analysis of this collaborative learning environment, we identified five design features for supporting teacher learning of important mathematics and pedagogy in a problem-solving setting. We discuss these design features in depth and illustrate them by presenting an elaborated example from the professional development. This study extends the existing guidance for the design of professional development by examining and operationalizing the relationships among research-based features of effective professional development and the enacted features of a particular design.

Constitutive Equation with Varying Parameters for Superplastic Flow Behavior

NASA Astrophysics Data System (ADS)

Guan, Zhiping; Ren, Mingwen; Jia, Hongjie; Zhao, Po; Ma, Pinkui

2014-03-01

In this study, constitutive equations for superplastic materials with an extra large elongation were investigated through mechanical analysis. From the view of phenomenology, firstly, some traditional empirical constitutive relations were standardized by restricting some strain paths and parameter conditions, and the coefficients in these relations were strictly given new mechanical definitions. Subsequently, a new, general constitutive equation with varying parameters was theoretically deduced based on the general mechanical equation of state. The superplastic tension test data of Zn-5%Al alloy at 340 °C under strain rates, velocities, and loads were employed for building a new constitutive equation and examining its validity. Analysis results indicated that the constitutive equation with varying parameters could characterize superplastic flow behavior in practical superplastic forming with high prediction accuracy and without any restriction of strain path or deformation condition, showing good industrial or scientific interest. On the contrary, those empirical equations have low prediction capabilities due to constant parameters and poor applicability because of the limit of special strain path or parameter conditions based on strict phenomenology.

The Incompatibility of Materialism and the Desire for Children: Psychological Insights into the Fertility Discrepancy among Modern Countries

ERIC Educational Resources Information Center

Li, Norman P.; Patel, Lily; Balliet, Daniel; Tov, William; Scollon, Christie N.

2011-01-01

We examined factors related to attitudes toward marriage and the importance of having children in both the US and Singapore. Path analysis indicated that life dissatisfaction leads to materialism, and both of these factors lead to favorable attitudes toward marriage, which leads to greater desire for children. Further analysis indicated this model…

Lending Officers' Decisions to Recommend Innovative Agricultural Technology.

ERIC Educational Resources Information Center

McIntosh, Wm. Alex; Zey-Ferrell, Mary

1986-01-01

Path analysis examines an analytical model of decision making by lending officers of 211 Texas banks when recommending agricultural technology to farmer-clients. Model analyzes effects of loan officers' ascribed/achieved personal characteristics and perceptions of organizational constraints during three stages of decision process: using…

Mid-L/D Lifting Body Entry Demise Analysis

NASA Technical Reports Server (NTRS)

Ling, Lisa

2017-01-01

The mid-lift-to-drag ratio (mid-L/D) lifting body is a fully autonomous spacecraft under design at NASA for enabling a rapid return of scientific payloads from the International Space Station (ISS). For contingency planning and risk assessment for the Earth-return trajectory, an entry demise analysis was performed to examine three potential failure scenarios: (1) nominal entry interface conditions with loss of control, (2) controlled entry at maximum flight path angle, and (3) controlled entry at minimum flight path angle. The objectives of the analysis were to predict the spacecraft breakup sequence and timeline, determine debris survival, and calculate the debris dispersion footprint. Sensitivity analysis was also performed to determine the effect of the initial pitch rate on the spacecraft stability and breakup during the entry. This report describes the mid-L/D lifting body and presents the results of the entry demise and sensitivity analyses.

Relationships among sense of coherence, oral health status, nutritional status and care need level of older adults according to path analysis.

PubMed

Dewake, Nanae; Hamasaki, Tomoko; Sakai, Rie; Yamada, Shima; Nima, Yuko; Tomoe, Miki; Kakuta, Satoko; Iwasaki, Masanori; Soh, Inho; Shimazaki, Yoshihiro; Ansai, Toshihiro

2017-11-01

Sense of coherence (SOC) is a measurement of ability of an individual to cope with psychological stress and remain in good health. The aim of the present study was to examine the relationships among SOC score, oral health status, nutritional status and care need level of older adults using path analysis. We enrolled 53 older adults (17 men and 36 women) who were attending a day care service (mean age 80.4 ± 6.5 years). SOC was assessed using a 13-item, seven-scale instrument. Oral health status (number of present teeth, denture use) and nutritional status (assessed with Mini-Nutritional Assessment Short-Form) were also evaluated. Path analysis was used to examine the relationship of SOC with other related factors, including care need level. The mean SOC score was 57.0 ± 13.9. Mini-Nutritional Assessment Short-Form results showed that one participant (1.8%) was malnourished, 26 (49.1%) were at risk of malnutrition and 26 (49.1%) had normal nutritional status. Participants with high SOC scores showed a strong positive attitude, had a relatively large number of teeth, were in good nutritional condition and showed low care need levels. The present results showed that maintaining a high SOC level and good oral health help to reduce care need levels in older adults, and also prevent a worsening of their nutritional condition. Geriatr Gerontol Int 2017; 17: 2083-2088. © 2017 Japan Geriatrics Society.

Methamphetamine Use among Homeless Former Foster Youth: The Mediating Role of Social Networks

PubMed Central

Yoshioka-Maxwell, Amanda; Rice, Eric; Rhoades, Harmony; Winetrobe, Hailey

2015-01-01

Objectives Social network analysis can provide added causal insight into otherwise confusing epidemiologic findings in public health research. Although foster care and homelessness are risk factors for methamphetamine use, current research has failed to explicate why homeless youth with foster care experience engage in methamphetamine use at higher rates than other homeless young adults. This study examined the mediating effect of network engagement and time spent homeless on the relationship between foster care experience and recent methamphetamine use among homeless youth in Los Angeles. Methods Egocentric network data from a cross-sectional community-based sample (n = 652) of homeless youth aged 13–25 were collected from drop-in centers in Los Angeles. Questions addressed foster care experience, time spent homeless, methamphetamine use, and perceived drug use in social networks. Path analysis was performed in SAS to examine mediation. Results Controlling for all other variables, results of path analysis regarding recent methamphetamine use indicated a direct effect between foster care experience and recent methamphetamine use (B = .269, t = 2.73, p < .01). However, this direct effect became statistically nonsignificant when time spent homeless and network methamphetamine use were added to the model, and indirect paths from time spent homeless and network methamphetamine use became statistically significant. Conclusions Foster care experience influenced recent methamphetamine use indirectly through time spent homeless and methamphetamine use by network members. Efforts to reduce methamphetamine use should focus on securing stable housing and addressing network interactions among homeless former foster youth. PMID:26146647

Habitat mosaics and path analysis can improve biological conservation of aquatic biodiversity in ecosystems with low-head dams

USGS Publications Warehouse

Hitchman, Sean M.; Mather, Martha E.; Smith, Joseph M.; Fencl, Jane S.

2018-01-01

Conserving native biodiversity depends on restoring functional habitats in the face of human-induced disturbances. Low-head dams are a ubiquitous human impact that degrades aquatic ecosystems worldwide. To improve our understanding of how low-head dams impact habitat and associated biodiversity, our research examined complex interactions among three spheres of the total environment. i.e., how low-head dams (anthroposphere) affect aquatic habitat (hydrosphere), and native biodiversity (biosphere) in streams and rivers. Creation of lake-like habitats upstream of low-head dams is a well-documented major impact of dams. Alterations downstream of low head dams also have important consequences, but these downstream dam effects are more challenging to detect. In a multidisciplinary field study at five dammed and five undammed sites within the Neosho River basin, KS, we tested hypotheses about two types of habitat sampling (transect and mosaic) and two types of statistical analyses (analysis of covariance and path analysis). We used fish as our example of biodiversity alteration. Our research provided three insights that can aid environmental professionals who seek to conserve and restore fish biodiversity in aquatic ecosystems threatened by human modifications. First, a mosaic approach identified habitat alterations below low-head dams (e.g. increased proportion of riffles) that were not detected using the more commonly-used transect sampling approach. Second, the habitat mosaic approach illustrated how low-head dams reduced natural variation in stream habitat. Third, path analysis, a statistical approach that tests indirect effects, showed how dams, habitat, and fish biodiversity interact. Specifically, path analysis revealed that low-head dams increased the proportion of riffle habitat below dams, and, as a result, indirectly increased fish species richness. Furthermore, the pool habitat that was created above low-head dams dramatically decreased fish species richness. As we show here, mosaic habitat sampling and path analysis can help conservation practitioners improve science-based management plans for disturbed aquatic systems worldwide.

Habitat mosaics and path analysis can improve biological conservation of aquatic biodiversity in ecosystems with low-head dams.

PubMed

Hitchman, Sean M; Mather, Martha E; Smith, Joseph M; Fencl, Jane S

2018-04-01

Conserving native biodiversity depends on restoring functional habitats in the face of human-induced disturbances. Low-head dams are a ubiquitous human impact that degrades aquatic ecosystems worldwide. To improve our understanding of how low-head dams impact habitat and associated biodiversity, our research examined complex interactions among three spheres of the total environment. i.e., how low-head dams (anthroposphere) affect aquatic habitat (hydrosphere), and native biodiversity (biosphere) in streams and rivers. Creation of lake-like habitats upstream of low-head dams is a well-documented major impact of dams. Alterations downstream of low head dams also have important consequences, but these downstream dam effects are more challenging to detect. In a multidisciplinary field study at five dammed and five undammed sites within the Neosho River basin, KS, we tested hypotheses about two types of habitat sampling (transect and mosaic) and two types of statistical analyses (analysis of covariance and path analysis). We used fish as our example of biodiversity alteration. Our research provided three insights that can aid environmental professionals who seek to conserve and restore fish biodiversity in aquatic ecosystems threatened by human modifications. First, a mosaic approach identified habitat alterations below low-head dams (e.g. increased proportion of riffles) that were not detected using the more commonly-used transect sampling approach. Second, the habitat mosaic approach illustrated how low-head dams reduced natural variation in stream habitat. Third, path analysis, a statistical approach that tests indirect effects, showed how dams, habitat, and fish biodiversity interact. Specifically, path analysis revealed that low-head dams increased the proportion of riffle habitat below dams, and, as a result, indirectly increased fish species richness. Furthermore, the pool habitat that was created above low-head dams dramatically decreased fish species richness. As we show here, mosaic habitat sampling and path analysis can help conservation practitioners improve science-based management plans for disturbed aquatic systems worldwide. Copyright © 2017 Elsevier B.V. All rights reserved.

Automatically visualise and analyse data on pathways using PathVisioRPC from any programming environment.

PubMed

Bohler, Anwesha; Eijssen, Lars M T; van Iersel, Martijn P; Leemans, Christ; Willighagen, Egon L; Kutmon, Martina; Jaillard, Magali; Evelo, Chris T

2015-08-23

Biological pathways are descriptive diagrams of biological processes widely used for functional analysis of differentially expressed genes or proteins. Primary data analysis, such as quality control, normalisation, and statistical analysis, is often performed in scripting languages like R, Perl, and Python. Subsequent pathway analysis is usually performed using dedicated external applications. Workflows involving manual use of multiple environments are time consuming and error prone. Therefore, tools are needed that enable pathway analysis directly within the same scripting languages used for primary data analyses. Existing tools have limited capability in terms of available pathway content, pathway editing and visualisation options, and export file formats. Consequently, making the full-fledged pathway analysis tool PathVisio available from various scripting languages will benefit researchers. We developed PathVisioRPC, an XMLRPC interface for the pathway analysis software PathVisio. PathVisioRPC enables creating and editing biological pathways, visualising data on pathways, performing pathway statistics, and exporting results in several image formats in multiple programming environments. We demonstrate PathVisioRPC functionalities using examples in Python. Subsequently, we analyse a publicly available NCBI GEO gene expression dataset studying tumour bearing mice treated with cyclophosphamide in R. The R scripts demonstrate how calls to existing R packages for data processing and calls to PathVisioRPC can directly work together. To further support R users, we have created RPathVisio simplifying the use of PathVisioRPC in this environment. We have also created a pathway module for the microarray data analysis portal ArrayAnalysis.org that calls the PathVisioRPC interface to perform pathway analysis. This module allows users to use PathVisio functionality online without having to download and install the software and exemplifies how the PathVisioRPC interface can be used by data analysis pipelines for functional analysis of processed genomics data. PathVisioRPC enables data visualisation and pathway analysis directly from within various analytical environments used for preliminary analyses. It supports the use of existing pathways from WikiPathways or pathways created using the RPC itself. It also enables automation of tasks performed using PathVisio, making it useful to PathVisio users performing repeated visualisation and analysis tasks. PathVisioRPC is freely available for academic and commercial use at http://projects.bigcat.unimaas.nl/pathvisiorpc.

Cumulative trauma and symptom complexity in children: a path analysis.

PubMed

Hodges, Monica; Godbout, Natacha; Briere, John; Lanktree, Cheryl; Gilbert, Alicia; Kletzka, Nicole Taylor

2013-11-01

Multiple trauma exposures during childhood are associated with a range of psychological symptoms later in life. In this study, we examined whether the total number of different types of trauma experienced by children (cumulative trauma) is associated with the complexity of their subsequent symptomatology, where complexity is defined as the number of different symptom clusters simultaneously elevated into the clinical range. Children's symptoms in six different trauma-related areas (e.g., depression, anger, posttraumatic stress) were reported both by child clients and their caretakers in a clinical sample of 318 children. Path analysis revealed that accumulated exposure to multiple different trauma types predicts symptom complexity as reported by both children and their caretakers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Transitional Patterns of Adolescent Females in Non-Traditional Career Paths.

ERIC Educational Resources Information Center

Ciccocioppo, Anna-Lisa; Stewin, Leonard L.; Madill, Helen M.; Montgomerie, T. Craig; Tovell, Dorothy R.; Armour, Margaret-Ann; Fitzsimmons, George W.

2002-01-01

Examines the factors that affected the career decision-making of adolescent females and young women in undergraduate science, engineering, and technology programs. Qualitative analysis was used to uncover seven themes: transition from high school, educational influences, family influences, academic issues, coursework management, gender issues, and…

Theoretical analysis of the time-resolved binary (e, 2e) binding energy spectra on three-body photodissociation of acetone at 195 nm

NASA Astrophysics Data System (ADS)

Yamazaki, M.; Nakayama, S.; Zhu, C. Y.; Takahashi, M.

2017-11-01

We report on theoretical progress in time-resolved (e, 2e) electron momentum spectroscopy of photodissociation dynamics of the deuterated acetone molecule at 195 nm. We have examined the predicted minimum energy reaction path to investigate whether associated (e, 2e) calculations meet the experimental results. A noticeable difference between the experiment and calculations has been found at around binding energy of 10 eV, suggesting that the observed difference may originate, at least partly, in ever-unconsidered non-minimum energy paths.

Anxiety and Shame as Risk Factors for Depression, Suicidality, and Functional Impairment in Body Dysmorphic Disorder and Obsessive Compulsive Disorder.

PubMed

Weingarden, Hilary; Renshaw, Keith D; Wilhelm, Sabine; Tangney, June P; DiMauro, Jennifer

2016-11-01

Body dysmorphic disorder (BDD) and obsessive compulsive disorder (OCD) are associated with elevated depression, suicidality, functional impairment, and days housebound, yet little research has identified risk factors for these outcomes. Using path analysis, the present study examined anxiety and shame as risk factors for these outcomes across Internet-recruited self-report groups (BDD [n = 114], OCD [n = 114], and healthy control [HC; n = 133]). Paths from anxiety and shame to outcomes were similar and mostly significant across BDD and OCD, compared to non-significant paths for HCs, with one exception: the path from shame to depression was significant in the BDD group (b = 0.32) but non-significant in the OCD group (b = 0.07). Findings underscore similarities in BDD and OCD, supporting their reclassification into the same Obsessive Compulsive Related Disorders category. Results emphasize the importance of targeting shame, in addition to anxiety, in treatments for BDD and OCD.

Anxiety and Shame as Risk Factors for Depression, Suicidality, and Functional Impairment in Body Dysmorphic Disorder and Obsessive Compulsive Disorder

PubMed Central

Weingarden, Hilary; Renshaw, Keith D.; Wilhelm, Sabine; Tangney, June P.; DiMauro, Jennifer

2016-01-01

Body dysmorphic disorder (BDD) and obsessive compulsive disorder (OCD) are associated with elevated depression, suicidality, functional impairment, and days housebound, yet little research has identified risk factors for these outcomes. Using path analysis, the present study examined anxiety and shame as risk factors for these outcomes across Internet-recruited self-report groups (BDD [n = 114], OCD [n = 114], and healthy control [HC; n = 133]. Paths from anxiety and shame to outcomes were similar and mostly significant across BDD and OCD, compared to non-significant paths for HCs, with one exception: the path from shame to depression was significant in the BDD group (b = .32) but non-significant in the OCD group (b = .07). Findings underscore similarities in BDD and OCD, supporting their reclassification into the same Obsessive Compulsive Related Disorders category. Results emphasize the importance of targeting shame, in addition to anxiety, in treatments for BDD and OCD. PMID:26998694

Crossing Boundaries: Nativity, Ethnicity, and Mate Selection

PubMed Central

Qian, Zhenchao; Glick, Jennifer E.; Baston, Christie

2016-01-01

The influx of immigrants has increased diversity among ethnic minorities and indicates that they may take multiple integration paths in American society. Previous research on ethnic integration often focuses on panethnic differences and few have explored ethnic diversity within a racial or panethnic context. Using 2000 U.S. census data for Puerto Rican, Mexican, Chinese, and Filipino origin individuals, we examine differences in marriage and cohabitation with whites, with other minorities, within a panethnic group, and within an ethnic group by nativity status. Ethnic endogamy is strong and, to a less extent, so is panethnic endogamy. Yet, marital or cohabiting unions with whites remain an important path of integration but differ significantly by ethnicity, nativity, age at arrival, and educational attainment. Meanwhile, ethnic differences in marriage and cohabitation with other racial or ethnic minorities are strong. Our analysis supports that unions with whites remain a major path of integration, but other paths of integration also become viable options for all ethnic groups. PMID:22350840

Psychological Empowerment and Child Welfare Worker Outcomes: A Path Analysis

ERIC Educational Resources Information Center

Lee, Joohee; Weaver, Cynthia; Hrostowski, Susan

2011-01-01

The purpose of this study was to investigate how work environment and psychological empowerment related to worker outcomes in public child welfare. These relationships were examined by testing a conceptual model in which psychological empowerment mediated the relationships between work environment variables (quality of supervision and role…

Testing an Attachment Model of Latina/o College Students' Psychological Adjustment

ERIC Educational Resources Information Center

Garriott, Patton O.; Love, Keisha M.; Tyler, Kenneth M.; Thomas, Deneia M.; Roan-Belle, Clarissa R.; Brown, Carrie L.

2010-01-01

The present study examined the influence of attachment relationships on the psychological adjustment of Latina/o university students (N = 80) attending predominantly White institutions of higher education. A path analysis conducted to test a hypothesized model of parent and peer attachment, self-esteem, and psychological distress indicated that…

Online Metacognitive Strategies, Hypermedia Annotations, and Motivation on Hypertext Comprehension

ERIC Educational Resources Information Center

Shang, Hui-Fang

2016-01-01

This study examined the effect of online metacognitive strategies, hypermedia annotations, and motivation on reading comprehension in a Taiwanese hypertext environment. A path analysis model was proposed based on the assumption that if English as a foreign language learners frequently use online metacognitive strategies and hypermedia annotations,…

Further Education Pathways of Canadian University Graduates

ERIC Educational Resources Information Center

Adamuti-Trache, Maria

2008-01-01

Through secondary analysis of the National Graduate Survey data, this study examines determinants of choice of further education pathways by Canadian university graduates in early 2000s. This paper extends the Cross' participation model by introducing a typology of path choices that are related to socio-demographic, post-secondary and situational…

Field Theory in Organizational Psychology: An Analysis of Theoretical Approaches in Leadership.

ERIC Educational Resources Information Center

Garcia, Joseph E.

This literature review examines Kurt Lewin's influence in leadership psychology. Characteristics of field theory are described in detail and utilized in analyzing leadership research, including the trait approach, leader behavior studies, contingency theory, path-goal theory, and leader decision theory. Important trends in leadership research are…

[Which route leads from chronic back pain to depression? A path analysis on direct and indirect effects using the cognitive mediators catastrophizing and helplessness/hopelessness in a general population sample].

PubMed

Fahland, R A; Kohlmann, T; Hasenbring, M; Feng, Y-S; Schmidt, C O

2012-12-01

Chronic pain and depression are highly comorbid; however, the longitudinal link is only partially understood. This study examined direct and indirect effects of chronic back pain on depression using path analysis in a general population sample, focussing on cognitive mediator variables. Analyses are based on 413 participants (aged 18-75 years) in a population-based postal survey on back pain who reported chronic back pain at baseline. Follow-up data were collected after 1 year. Depression was measured with the Center for Epidemiologic Studies Depression Scale (CES-D). Fear-avoidance-beliefs (FABQ), catastrophizing and helplessness/hopelessness (KRSS) were considered as cognitive mediators. Data were analyzed using path analysis. Chronic back pain had no direct effect on depression at follow-up when controlling for cognitive mediators. A mediating effect emerged for helplessness/hopelessness but not for catastrophizing or fear-avoidance beliefs. These results support the cognitive mediation hypothesis which assumes that psychological variables mediate the association between pain and depression. The importance of helplessness/hopelessness is of relevance for the treatment of patients with chronic back pain.

Between Domain Cognitive Dispersion and Functional Abilities in Older Adults

PubMed Central

Fellows, Robert P.; Schmitter-Edgecombe, Maureen

2016-01-01

Objective Within-person variability in cognitive performance is related to neurological integrity, but the association with functional abilities is less clear. The primary aim of this study was to examine the association between cognitive dispersion, or within-person variability, and everyday multitasking and the way in which these variables may influence performance on a naturalistic assessment of functional abilities. Method Participants were 156 community-dwelling adults, age 50 or older. Cognitive dispersion was calculated by measuring within-person variability in cognitive domains, established through principal components analysis. Path analysis was used to determine the independent contribution of cognitive dispersion to functional ability, mediated by multitasking. Results Results of the path analysis revealed that the number of subtasks interweaved (i.e., multitasked) mediated the association between cognitive dispersion and task sequencing and accuracy. Although increased multitasking was associated with worse task performance in the path model, secondary analyses revealed that for individuals with low cognitive dispersion, increased multitasking was associated with better task performance, whereas for those with higher levels of dispersion multitasking was negatively correlated with task performance. Conclusion These results suggest that cognitive dispersion between domains may be a useful indicator of multitasking and daily living skills among older adults. PMID:26300441

Effects of Glide Path on the Centering Ability and Preparation Time of Two Reciprocating Instruments

PubMed Central

Coelho, Marcelo Santos; Fontana, Carlos Eduardo; Kato, Augusto Shoji; de Martin, Alexandre Sigrist; da Silveira Bueno, Carlos Eduardo

2016-01-01

Introduction: The aim of this in vitro study was to evaluate the effects of establishing glide path on the centering ability and preparation time of two single-file reciprocating systems in mesial root canals of mandibular molars. Methods and Materials: Sixty extracted mandibular molars with curvatures of 25-39 degrees and separate foramina for the mesiobuccal and mesiolingual canals, were divided into four groups (n=15); WaveOne+glide path; WaveOne; Reciproc+glide path and Reciproc. Non-patent canals were excluded and only one canal in each tooth was instrumented. A manual glide path was established in first and third groups with #10, 15 and 20 hand K-files. Preparation was performed with reciprocating in-and-out motion, with a 3-4 mm amplitude and slight apical pressure. Initial and final radiographs were taken to analyze the amount of dentin removed in the instrumented canals. The radiographs were superimposed with an image editing software and examined to assess discrepancies at 3-, 6- and 9-mm distances from the apex. The Kruskal-Wallis test was used for statistical analysis. The level of significance was set at 0.05. Results: Preparation in groups without glide paths was swifter than the other groups (P=0.001). However, no difference was observed regarding centering ability. Conclusion: Establishing a glide path increased the total instrumentation time for preparing curved canals with WaveOne and Reciproc instruments. Glide path had no influence on the centering ability of these systems. PMID:26843875

A graph-based system for network-vulnerability analysis

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

Swiler, L.P.; Phillips, C.

1998-06-01

This paper presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The graph-based tool can identify the set of attack paths that have a high probability of success (or a low effort cost) for the attacker. The system could be used to test the effectiveness of making configuration changes, implementing an intrusion detection system, etc. The analysis system requires as input a database of common attacks,more » broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.« less

Negative emotionality moderates associations among attachment, toddler sleep, and later problem behaviors.

PubMed

Troxel, Wendy M; Trentacosta, Christopher J; Forbes, Erika E; Campbell, Susan B

2013-02-01

Secure parent-child relationships are implicated in children's self-regulation, including the ability to self-soothe at bedtime. Sleep, in turn, may serve as a pathway linking attachment security with subsequent emotional and behavioral problems in children. We used path analysis to examine the direct relationship between attachment security and maternal reports of sleep problems during toddlerhood and the degree to which sleep serves as a pathway linking attachment with subsequent teacher-reported emotional and behavioral problems. We also examined infant negative emotionality as a vulnerability factor that may potentiate attachment-sleep-adjustment outcomes. Data were drawn from 776 mother-infant dyads participating in the National Institute of Child and Human Development Study of Early Child Care. After statistically adjusting for mother and child characteristics, including child sleep and emotional and behavioral problems at 24 months, we found no evidence for a statistically significant direct path between attachment security and sleep problems at 36 months; however, there was a direct relationship between sleep problems at 36 months and internalizing problems at 54 months. Path models that examined the moderating influence of infant negative emotionality demonstrated significant direct relationships between attachment security and toddler sleep problems and between sleep problems and subsequent emotional and behavioral problems, but only among children characterized by high negative emotionality at 6 months. In addition, among this subset, there was a significant indirect path between attachment and internalizing problems through sleep problems. These longitudinal findings implicate sleep as one critical pathway linking attachment security with adjustment difficulties, particularly among temperamentally vulnerable children. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Behavior problems and placement change in a national child welfare sample: a prospective study.

PubMed

Aarons, Gregory A; James, Sigrid; Monn, Amy R; Raghavan, Ramesh; Wells, Rebecca S; Leslie, Laurel K

2010-01-01

There is ongoing debate regarding the impact of youth behavior problems on placement change in child welfare compared to the impact of placement change on behavior problems. Existing studies provide support for both perspectives. The purpose of this study was to prospectively examine the relations of behavior problems and placement change in a nationally representative sample of youths in the National Survey of Child and Adolescent Well-Being. The sample consisted of 500 youths in the child welfare system with out-of-home placements over the course of the National Survey of Child and Adolescent Well-Being study. We used a prospective cross-lag design and path analysis to examine reciprocal effects of behavior problems and placement change, testing an overall model and models examining effects of age and gender. In the overall model, out of a total of eight path coefficients, behavior problems significantly predicted placement changes for three paths and placement change predicted behavior problems for one path. Internalizing and externalizing behavior problems at baseline predicted placement change between baseline and 18 months. Behavior problems at an older age and externalizing behavior at 18 months appear to confer an increased risk of placement change. Of note, among female subjects, placement changes later in the study predicted subsequent internalizing and externalizing behavior problems. In keeping with recommendations from a number of professional bodies, we suggest that initial and ongoing screening for internalizing and externalizing behavior problems be instituted as part of standard practice for youths entering or transitioning in the child welfare system.

Negative Emotionality Moderates Associations among Attachment, Toddler Sleep, and Later Problem Behaviors

PubMed Central

Troxel, Wendy M.; Trentacosta, Christopher J.; Forbes, Erika E.; Campbell, Susan B.

2013-01-01

Secure parent-child relationships are implicated in children’s self-regulation, including the ability to self-soothe at bedtime. Sleep, in turn, may serve as a pathway linking attachment security with subsequent emotional and behavioral problems in children. We used path analysis to examine the direct relationship between attachment security and maternal-reports of sleep problems during toddlerhood, and the degree to which sleep serves as a pathway linking attachment with subsequent teacher-reported emotional and behavioral problems. We also examined infant negative emotionality as a vulnerability factor that may potentiate attachment-sleep-adjustment outcomes. Data were drawn from 776 mother-infant dyads participating in the NICHD Study of Early Child Care (SECC). In the full sample, after statistically adjusting for mother and child characteristics, including child sleep and emotional and behavioral problems at 24 months, we did not find evidence for a statistically significant direct path between attachment security and sleep problems at 36 months; however, there was a direct relationship between sleep problems at 36 months and internalizing problems at 54 months. Path models that examined the moderating influence of infant negative emotionality demonstrated significant direct relationships between attachment security and toddler sleep problems, and sleep problems and subsequent emotional and behavioral problems, but only among children characterized by high negative emotionality at 6 months of age. In addition, among this subset, there was a significant indirect path between attachment and internalizing problems through sleep problems. These longitudinal findings implicate sleep as one critical pathway linking attachment security with adjustment difficulties, particularly among temperamentally vulnerable children. PMID:23421840

Hippocampal atrophy and memory dysfunction associated with physical inactivity in community-dwelling elderly subjects: The Sefuri study.

PubMed

Hashimoto, Manabu; Araki, Yuko; Takashima, Yuki; Nogami, Kohjiro; Uchino, Akira; Yuzuriha, Takefumi; Yao, Hiroshi

2017-02-01

Physical inactivity is one of the modifiable risk factors for hippocampal atrophy and Alzheimer's disease. We investigated the relationship between physical activity, hippocampal atrophy, and memory using structural equation modeling (SEM). We examined 213 community-dwelling elderly subjects (99 men and 114 women with a mean age of 68.9 years) without dementia or clinically apparent depression. All participants underwent Mini-Mental State Examination (MMSE) and Rivermead Behavioral Memory Test (RBMT). Physical activities were assessed with a structured questionnaire. We evaluated the degree of hippocampal atrophy (z-score-referred to as ZAdvance hereafter), using a free software program-the voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) based on statistical parametric mapping 8 plus Diffeomorphic Anatomical Registration Through an Exponentiated Lie algebra. Routine magnetic resonance imaging findings were as follows: silent brain infarction, n  = 24 (11.3%); deep white matter lesions, n  = 72 (33.8%); periventricular hyperintensities, n  = 35 (16.4%); and cerebral microbleeds, n  = 14 (6.6%). Path analysis based on SEM indicated that the direct paths from leisure-time activity to hippocampal atrophy (β = -.18, p  < .01) and from hippocampal atrophy to memory dysfunction (RBMT) (β = -.20, p  < .01) were significant. Direct paths from "hippocampus" gray matter volume to RBMT and MMSE were highly significant, while direct paths from "whole brain" gray matter volume to RBMT and MMSE were not significant. The presented SEM model fit the data reasonably well. Based on the present SEM analysis, we found that hippocampal atrophy was associated with age and leisure-time physical inactivity, and hippocampal atrophy appeared to cause memory dysfunction, although we are unable to infer a causal or temporal association between hippocampal atrophy and memory dysfunction from the present observational study.

Co-development of manner and path concepts in language, action, and eye-gaze behavior.

PubMed

Lohan, Katrin S; Griffiths, Sascha S; Sciutti, Alessandra; Partmann, Tim C; Rohlfing, Katharina J

2014-07-01

In order for artificial intelligent systems to interact naturally with human users, they need to be able to learn from human instructions when actions should be imitated. Human tutoring will typically consist of action demonstrations accompanied by speech. In the following, the characteristics of human tutoring during action demonstration will be examined. A special focus will be put on the distinction between two kinds of motion events: path-oriented actions and manner-oriented actions. Such a distinction is inspired by the literature pertaining to cognitive linguistics, which indicates that the human conceptual system can distinguish these two distinct types of motion. These two kinds of actions are described in language by more path-oriented or more manner-oriented utterances. In path-oriented utterances, the source, trajectory, or goal is emphasized, whereas in manner-oriented utterances the medium, velocity, or means of motion are highlighted. We examined a video corpus of adult-child interactions comprised of three age groups of children-pre-lexical, early lexical, and lexical-and two different tasks, one emphasizing manner more strongly and one emphasizing path more strongly. We analyzed the language and motion of the caregiver and the gazing behavior of the child to highlight the differences between the tutoring and the acquisition of the manner and path concepts. The results suggest that age is an important factor in the development of these action categories. The analysis of this corpus has also been exploited to develop an intelligent robotic behavior-the tutoring spotter system-able to emulate children's behaviors in a tutoring situation, with the aim of evoking in human subjects a natural and effective behavior in teaching to a robot. The findings related to the development of manner and path concepts have been used to implement new effective feedback strategies in the tutoring spotter system, which should provide improvements in human-robot interaction. Copyright © 2014 Cognitive Science Society, Inc.

The relationship between South Korean clinical nurses' attitudes toward organizations and voluntary turnover intention: A path analysis.

PubMed

Kim, Jong Kyung; Chang, Sun Ju

2015-08-01

The purpose of this study was to examine the relationship between attitudes toward their organizations and voluntary turnover intention among South Korean clinical nurses. Data from a total of 312 clinical nurses in six hospitals in South Korea were collected for the study. Both hierarchical multiple regression analysis and path analysis were used to analyse the data. The overall fit of the hypothetical model was good. Voluntary turnover intention was found to have significant direct pathways to job embeddedness and organizational commitment. Organizational commitment and satisfaction with organizational rewards had indirect pathways to voluntary turnover intention through job embeddedness. All variances explained 62.3% of the voluntary turnover intention scores. The findings suggest that greater job embeddedness, organizational commitment and satisfaction with organizational rewards lead to lower voluntary turnover intention among clinical nurses in South Korea. © 2014 Wiley Publishing Asia Pty Ltd.

Thermal elastohydrodynamic lubrication of spur gears

NASA Technical Reports Server (NTRS)

Wang, K. L.; Cheng, H. S.

1980-01-01

An analysis and computer program called TELSGE were developed to predict the variations of dynamic load, surface temperature, and lubricant film thickness along the contacting path during the engagement of a pair of involute spur gears. The analysis of dynamic load includes the effect of gear inertia, the effect of load sharing of adjacent teeth, and the effect of variable tooth stiffness which are obtained by a finite-element method. Results obtained from TELSGE for the dynamic load distributions along the contacting path for various speeds of a pair of test gears show patterns similar to that observed experimentally. Effects of damping ratio, contact ratio, tip relief, and tooth error on the dynamic load were examined. In addition, two dimensionless charts are included for predicting the maximum equilibrium surface temperature, which can be used to estimate directly the lubricant film thickness based on well established EHD analysis.

Which way and how far? Tracking of translation and rotation information for human path integration.

PubMed

Chrastil, Elizabeth R; Sherrill, Katherine R; Hasselmo, Michael E; Stern, Chantal E

2016-10-01

Path integration, the constant updating of the navigator's knowledge of position and orientation during movement, requires both visuospatial knowledge and memory. This study aimed to develop a systems-level understanding of human path integration by examining the basic building blocks of path integration in humans. To achieve this goal, we used functional imaging to examine the neural mechanisms that support the tracking and memory of translational and rotational components of human path integration. Critically, and in contrast to previous studies, we examined movement in translation and rotation tasks with no defined end-point or goal. Navigators accumulated translational and rotational information during virtual self-motion. Activity in hippocampus, retrosplenial cortex (RSC), and parahippocampal cortex (PHC) increased during both translation and rotation encoding, suggesting that these regions track self-motion information during path integration. These results address current questions regarding distance coding in the human brain. By implementing a modified delayed match to sample paradigm, we also examined the encoding and maintenance of path integration signals in working memory. Hippocampus, PHC, and RSC were recruited during successful encoding and maintenance of path integration information, with RSC selective for tasks that required processing heading rotation changes. These data indicate distinct working memory mechanisms for translation and rotation, which are essential for updating neural representations of current location. The results provide evidence that hippocampus, PHC, and RSC flexibly track task-relevant translation and rotation signals for path integration and could form the hub of a more distributed network supporting spatial navigation. Hum Brain Mapp 37:3636-3655, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Activity as a predictor of mental well-being among older adults.

PubMed

Lampinen, P; Heikkinen, R-L; Kauppinen, M; Heikkinen, E

2006-09-01

This eight-year follow-up study examines the roles of physical and leisure activity as predictors of mental well-being among older adults born in 1904-1923. As part of the Evergreen project, 1224 (80%) persons aged 65-84 years were interviewed at baseline (1988), and 663 (90%) persons in the follow-up (1996). Mental well-being factors including depressive symptoms, anxiety, loneliness, self-rated mental vigour and meaning in life were constructed using factor analysis. The predictors of mental well-being included physical and leisure activity, mobility status and number of chronic illnesses. We used a path analysis model to examine the predictors of mental well-being. At baseline, low number of chronic illnesses, better mobility status and leisure activity were associated with mental well-being. Baseline mental well-being, better mobility status and younger age predicted mental well-being in the follow-up. Explanatory power of the path analysis model for the mental well-being factor at baseline was 19% and 35% in the follow-up. These findings suggest that mental well-being in later life is associated with activity, better health and mobility status, which should become targets for preventive measures.

The Effect of Absorptive Capacity Perceptions on the Context Aware Ubiquitous Learning Acceptance

ERIC Educational Resources Information Center

Lin, Hsiu-Fen

2013-01-01

Purpose: The purpose of this study is to examine the impact of absorptive capacity (understanding, assimilating and applying u-learning) perceptions on behavioral intention to use u-learning through path analysis and applies the technology acceptance model (TAM) as a theoretical foundation, simultaneously improving the model by adopting prior…

Are My Students Like Me? The Path to Color-Blindness and White Racial Identity Development

ERIC Educational Resources Information Center

Bloom, Diane S.; Peters, Terri; Margolin, Marcia; Fragnoli, Kristi

2015-01-01

This study examines the White racial identity (WRI) development of pre-service teachers in diverse and nondiverse student teaching placements. A qualitative design, using constant comparative analysis yielded salient themes/categories. Our results provide evidence that experience in diverse settings might provide opportunities for individuals to…

Examining the Interrelations among Knowledge, Interests, and Learning Strategies

ERIC Educational Resources Information Center

Shen, Bo; Chen, Ang

2006-01-01

Guided by the Model of Domain Learning (MDL), the study was designed to explore the extent of interrelations among prior knowledge, learning strategies, interests, physical engagement, and learning outcomes in a sixth-grade (N = 91) volleyball unit. Pearson product-moment correlations and a path analysis were conducted for the research purpose.…

Mexican Americans in Higher Education: Cultural Adaptation and Marginalization as Predictors of College Persistence Intentions and Life Satisfaction

ERIC Educational Resources Information Center

Ojeda, Lizette; Castillo, Linda G.; Rosales Meza, Rocío; Piña-Watson, Brandy

2014-01-01

This study examined how college persistence intentions and life satisfaction influenced by acculturation, enculturation, White marginalization, and Mexican American marginalization among 515 Mexican American college students. The utility of a path analysis model was supported. Enculturation positively predicted persistence and life satisfaction.…

The Measurement of Change in English Language Proficiency

ERIC Educational Resources Information Center

Nallaya, Sasikala

2012-01-01

This study investigated the measurement of change in English language proficiency levels of pre-service and in-service teachers enrolled in a public university in Malaysia. Path analysis was used to measure change on three occasions by examining the effects of student characteristics, learning needs and multimodal technology on proficiency levels.…

Perceived Discrimination Experiences and Mental Health of Latina/o American Persons

ERIC Educational Resources Information Center

Moradi, Bonnie; Risco, Cristina

2006-01-01

With a sample of 128 Latina/o persons, the present study examined a model that tested direct, indirect, and mediated relations among perceived discrimination, psychological distress, self-esteem, sense of personal control, and acculturation to Latina/o and U.S. cultures. Path analysis of the model indicated that (a) perceived discrimination was…

Career Patterns: A Twenty-Year Panel Study

ERIC Educational Resources Information Center

Biemann, Torsten; Zacher, Hannes; Feldman, Daniel C.

2012-01-01

Using 20years of employment and job mobility data from a representative German sample (N = 1259), we employ optimal matching analysis (OMA) to identify six career patterns which deviate from the traditional career path of long-term, full-time employment in one organization. Then, in further analyses, we examine which socio-demographic predictors…

Coping, Reasons for Living, and Suicide in Black College Students

ERIC Educational Resources Information Center

Wang, Mei-Chuan; Nyutu, Pius N.; Tran, Kimberly K.

2012-01-01

The authors examined the roles of reasons for living and coping in protecting against suicidal behaviors among 361 Black college students. Results of a path analysis revealed that reasons for living mediated against suicidal ideation through an inverse effect on depression. Results also indicated that greater use of emotion-oriented coping may…

Testing a Model of Special Educators' Intent to Stay in Teaching.

ERIC Educational Resources Information Center

Cross, Lawrence H.; Billingsley, Bonnie S.

1994-01-01

This study used path analysis to examine the effects of work-related factors--including principal support, stress, role problems, job satisfaction, and commitment--on 542 Virginia special educators' expressions of intent to stay in teaching. The study concluded that these work-related variables should be included in strategies for retaining…

The Effect of SDLR and Self-efficacy in Preschool Teachers by Using WS Learning

ERIC Educational Resources Information Center

Kao, C-P.

2016-01-01

This study examined whether self-directed learning readiness (SDLR) moderates the association between Internet self-efficacy and approaches to learning by web searching (ALWS). A total of 329 valid questionnaires were used for the correlation and path analysis. The results revealed that preschool teachers' SDLR significantly moderated the…

Identity Styles and Religiosity: Examining the Role of Identity Commitment

ERIC Educational Resources Information Center

Grajales, Tevni E.; Sommers, Brittany

2016-01-01

This study observed the role of identity styles, identity commitment, and identity statuses in predicting religiosity in a sample of undergraduate students attending a Seventh-day Adventist university (N = 138). Two structural models were evaluated via path analysis. Results revealed two strong models for the prediction of religiosity. Identity…

Examining Identity Styles and Religiosity among Chilean Undergraduate Students

ERIC Educational Resources Information Center

Grajales, Tevni E.; Leon, Vicente; Al Nasser, Fatimah; Hooley, Esther; Sample, Melina; Sommers, Brittany

2016-01-01

This study tested Berzsonky's theory of identity styles and identity commitment in predicting religiosity. Participants were university students (N = 320) from Chile who were surveyed with the ISI-3 and BRS-6 instruments to measure identity styles and religiosity. Path analysis was used to test the model, which suggested that the three identity…

Administrative Support and Its Mediating Effect on US Public School Teachers

ERIC Educational Resources Information Center

Tickle, Benjamin R.; Chang, Mido; Kim, Sunha

2011-01-01

This study examined the effect of administrative support on teachers' job satisfaction and intent to stay in teaching. The study employed a path analysis to the data of regular, full-time, public school teachers from the Schools and Staffing Survey teacher questionnaire. Administrative support was the most significant predictor of teachers' job…

Attachment, Well-Being, and College Senior Concerns about the Transition out of College

ERIC Educational Resources Information Center

Lane, Joel A.

2016-01-01

This study examined the relationships among attachment, psychological well-being (PWB), life satisfaction, and concerns about the transition out of college among a sample of college seniors. A path analysis was conducted predicting that PWB and life satisfaction would mediate the relationships between attachment and 3 types of graduation…

Students' Perspectives on University Experiences; The Role of Protective Factors in Students' Lives

ERIC Educational Resources Information Center

Jdaitawi, Malek; Maya-Panorama; Nawafleh, Ahmad; Nabrawi, Ismaeel; Talafha, Feras; Mohd, Amani

2013-01-01

This study examined the relationship between protective factors and students' university experiences among 289 first year university students. The study made use of exploratory and confirmatory factor analyses to reveal initial support for the research variables. In addition, path analysis was utilized to investigate the relationship among the…

Relations between Goals, Self-Efficacy, Critical Thinking and Deep Processing Strategies: A Path Analysis

ERIC Educational Resources Information Center

Phan, Huy Phuong

2009-01-01

Research exploring students' academic learning has recently amalgamated different motivational theories within one conceptual framework. The inclusion of achievement goals, self-efficacy, deep processing and critical thinking has been cited in a number of studies. This article discusses two empirical studies that examined these four theoretical…

Teachers' Collective Efficacy, Job Satisfaction, and Job Stress in Cross-Cultural Context

ERIC Educational Resources Information Center

Klassen, Robert M.; Usher, Ellen L.; Bong, Mimi

2010-01-01

This study examines how teachers' collective efficacy (TCE), job stress, and the cultural dimension of collectivism are associated with job satisfaction for 500 teachers from Canada, Korea (South Korea or Republic of Korea), and the United States. Multigroup path analysis revealed that TCE predicted job satisfaction across settings. Job stress was…

Adaptive Strategies, Gender Ideology, and Work-Family Balance among Dutch Dual Earners

ERIC Educational Resources Information Center

Wierda-Boer, Hilde H.; Gerris, Jan R. M.; Vermulst, Ad A.

2008-01-01

Using questionnaire data on 149 Dutch dual-earner couples with young children participating in the European Famwork study, we examine how adaptive strategies and gender ideology relate to parents' perceived success in balancing work and family. Path analysis indicates that some adaptive strategies may harm individuals' work-family balance,…

Using the Health Belief Model to Predict Bystander Behavior among College Students

ERIC Educational Resources Information Center

Blavos, Alexis A.; Glassman, Tavis; Sheu, Jiunn-Jye; Diehr, Aaron; Deakins, Bethany

2014-01-01

This investigation used the Health Belief Model (HBM) to examine perceived barriers and benefits college students hold concerning medical amnesty. Researchers employed a cross-sectional research design with 369 students completing the survey (97% response rate). A path analysis revealed that college students are more likely to seek help during an…

The Effects of a Multiyear Universal Social-Emotional Learning Program: The Role of Student and School Characteristics

ERIC Educational Resources Information Center

Bierman, Karen L.; Coie, John D.; Dodge, Kenneth A.; Greenberg, Mark T.; Lochman, John E.; McMahon, Robert J.; Pinderhughes, Ellen

2010-01-01

Objective: This article examines the impact of a universal social-emotional learning program, the Fast Track PATHS (Promoting Alternative Thinking Strategies) curriculum and teacher consultation, embedded within the Fast Track selective prevention model. Method: The longitudinal analysis involved 2,937 children of multiple ethnicities who remained…

Components of Reflection: A Longitudinal Analysis of Study Abroad Student Blog Posts

ERIC Educational Resources Information Center

Savicki, Victor; Price, Michele V.

2017-01-01

Reflection supports actively transforming perspectives regarding study abroad experiences. The current study examines the "how" of reflection. Content of reflections is dictated by questions posed. The process of reflection is less prescribed yet revealing of paths to student understanding. Students posted to a web log (blog) over six…

Longitudinal Examination of Optimism, Personal Self-Efficacy and Student Well-Being: A Path Analysis

ERIC Educational Resources Information Center

Phan, Huy P.

2016-01-01

The present longitudinal study, based on existing theoretical tenets, explored a conceptual model that depicted four major orientations: optimism, self-efficacy, and academic well-being. An important question for consideration, in this case, involved the testing of different untested trajectories that could explain and predict individuals'…

Brief report: identity processes in Filipino late adolescents and young adults: parental influences and mental health outcomes.

PubMed

Pesigan, Ivan Jacob Agaloos; Luyckx, Koen; Alampay, Liane Peña

2014-07-01

This study focused on a process-oriented approach to identity formation using a sample of Filipino late adolescents and young adults (17-30 years; N = 779). Indirect relations between parenting and mental health via identity formation processes were examined. Two parenting dimensions (psychological control and support), two types of mental health outcomes (depression and psychological well-being), and five identity dimensions (commitment making (CM), identification with commitment (IC), exploration in breadth (EB), exploration in depth (ED), and ruminative exploration (RE)) were assessed. Recursive path analysis showed indirect relations between parenting and mental health via EB, ED, RE, and IC. Model differences between late adolescents (17-21 year olds) and young adults (22-30 year olds) were examined using multigroup path analysis. Results showed that the direct effect of psychological control on RE, and its indirect effect on depression through RE differed between the age groups. Implications and suggestions for future research are provided. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Validation of luminescent source reconstruction using spectrally resolved bioluminescence images

NASA Astrophysics Data System (ADS)

Virostko, John M.; Powers, Alvin C.; Jansen, E. D.

2008-02-01

This study examines the accuracy of the Living Image® Software 3D Analysis Package (Xenogen, Alameda, CA) in reconstruction of light source depth and intensity. Constant intensity light sources were placed in an optically homogeneous medium (chicken breast). Spectrally filtered images were taken at 560, 580, 600, 620, 640, and 660 nanometers. The Living Image® Software 3D Analysis Package was employed to reconstruct source depth and intensity using these spectrally filtered images. For sources shallower than the mean free path of light there was proportionally higher inaccuracy in reconstruction. For sources deeper than the mean free path, the average error in depth and intensity reconstruction was less than 4% and 12%, respectively. The ability to distinguish multiple sources decreased with increasing source depth and typically required a spatial separation of twice the depth. The constant intensity light sources were also implanted in mice to examine the effect of optical inhomogeneity. The reconstruction accuracy suffered in inhomogeneous tissue with accuracy influenced by the choice of optical properties used in reconstruction.

Effect of the Glide Path Establishment on the Torque Generation to the Files during Instrumentation: An In Vitro Measurement.

PubMed

Kwak, Sang Won; Ha, Jung-Hong; Cheung, Gary Shun-Pan; Kim, Hyeon-Cheol; Kim, Sung Kyo

2018-03-01

The purpose of this study was to compare in vitro torque generation during instrumentation with or without glide path establishment. Endo-training resin blocks with J-shaped canals were randomly divided into 2 groups according to glide path establishment (with or without) and subdivided into 2 subgroups with shaping instruments (WaveOne [Dentsply Maillefer, Ballaigues, Switzerland] or WaveOne Gold [Dentsply Maillefer]) (n = 15). For the glide path-established group, the glide path was prepared using ProGlider (Dentsply Maillefer). During the instrumentation with WaveOne or WaveOne Gold, in vitro torque was measured. The acquired data were analyzed with software. The maximum torque and total torque (the sum of the generated torque) were calculated. The data were statistically evaluated using 2-way analysis of variance and the Duncan post hoc comparison to examine any correlation of torque generation with glide path establishment and nickel-titanium instruments. The significance level was set at 95%. The generated total torque by WaveOne Gold was significantly reduced by glide path establishment (P < .05), whereas glide path establishment did not induce significant changes in the maximum torque for both file systems. WaveOne Gold with a glide path showed the lowest total torque generation among all groups (P < .05). WaveOne generated a higher maximum torque than WaveOne Gold regardless of the establishment of a glide path (P < .05). Under the limitations of this study, glide path establishment and the mechanical property of instruments have a significant influence on torque generation. It is recommended to create the glide path and use a flexible file to reduce torque generation and, consequently, the risk of file fracture and root dentin damage. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A graph-based network-vulnerability analysis system

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

Swiler, L.P.; Phillips, C.; Gaylor, T.

1998-05-03

This paper presents a graph based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example themore » class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level of effort for the attacker, various graph algorithms such as shortest path algorithms can identify the attack paths with the highest probability of success.« less

A graph-based network-vulnerability analysis system

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

Swiler, L.P.; Phillips, C.; Gaylor, T.

1998-01-01

This report presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the classmore » of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.« less

Scene perception and the visual control of travel direction in navigating wood ants

PubMed Central

Collett, Thomas S.; Lent, David D.; Graham, Paul

2014-01-01

This review reflects a few of Mike Land's many and varied contributions to visual science. In it, we show for wood ants, as Mike has done for a variety of animals, including readers of this piece, what can be learnt from a detailed analysis of an animal's visually guided eye, head or body movements. In the case of wood ants, close examination of their body movements, as they follow visually guided routes, is starting to reveal how they perceive and respond to their visual world and negotiate a path within it. We describe first some of the mechanisms that underlie the visual control of their paths, emphasizing that vision is not the ant's only sense. In the second part, we discuss how remembered local shape-dependent and global shape-independent features of a visual scene may interact in guiding the ant's path. PMID:24395962

Detection, Evaluation, and Optimization of Optical Signals Generated by Fiber Optic Bragg Gratings Under Dynamic Excitations

NASA Technical Reports Server (NTRS)

Adamovsky, Grigory; Lekki, John; Lock, James A.

2002-01-01

The dynamic response of a fiber optic Bragg grating to mechanical vibrations is examined both theoretically and experimentally. The theoretical expressions describing the consequences of changes in the grating's reflection spectrum are derived for partially coherent beams in an interferometer. The analysis is given in terms of the dominant wavelength, optical bandwidth, and optical path difference of the interfering signals. Changes in the reflection spectrum caused by a periodic stretching and compression of the grating were experimentally measured using an unbalanced Michelson interferometer, a Michelson interferometer with a non-zero optical path difference. The interferometer's sensitivity to changes in dominant wavelength of the interfering beams was measured as a function of interferometer unbalance and was compared to theoretical predictions. The theoretical analysis enables the user to determine the optimum performance for an unbalanced interferometer.

The impact of path crossing on visuo-spatial serial memory: encoding or rehearsal effect?

PubMed

Parmentier, Fabrice B R; Andrés, Pilar

2006-11-01

The determinants of visuo-spatial serial memory have been the object of little research, despite early evidence that not all sequences are equally remembered. Recently, empirical evidence was reported indicating that the complexity of the path formed by the to-be-remembered locations impacted on recall performance, defined for example by the presence of crossings in the path formed by successive locations (Parmentier, Elford, & Maybery, 2005). In this study, we examined whether this effect reflects rehearsal or encoding processes. We examined the effect of a retention interval and spatial interference on the ordered recall of spatial sequences with and without path crossings. Path crossings decreased recall performance, as did a retention interval. In line with the encoding hypothesis, but in contrast with the rehearsal hypothesis, the effect of crossing was not affected by the retention interval nor by tapping. The possible nature of the impact of path crossing on encoding mechanisms is discussed.

Effects of urban sprawl and vehicle miles traveled on traffic fatalities.

PubMed

Yeo, Jiho; Park, Sungjin; Jang, Kitae

2015-01-01

Previous research suggests that urban sprawl increases auto-dependency and that excessive auto use increases the risk of traffic fatalities. This indirect effect of urban sprawl on traffic fatalities is compared to non-vehicle miles traveled (VMT)-related direct effect of sprawl on fatalities. We conducted a path analysis to examine the causal linkages among urban sprawl, VMT, traffic fatalities, income, and fuel cost. The path diagram includes 2 major linkages: the direct relationship between urban sprawl and traffic fatalities and the indirect effect on fatalities through increased VMT in sprawling urban areas. To measure the relative strength of these causal linkages, path coefficients are estimated using data collected nationally from 147 urbanized areas in the United States. Through both direct and indirect paths, urban sprawl is associated with greater numbers of traffic fatalities, but the direct effect of sprawl on fatalities is more influential than the indirect effect. Enhancing traffic safety can be achieved by impeding urban sprawl and encouraging compact development. On the other hand, policy tools reducing VMT may be less effective than anticipated for traffic safety.

A Statistical Simulation Approach to Safe Life Fatigue Analysis of Redundant Metallic Components

NASA Technical Reports Server (NTRS)

Matthews, William T.; Neal, Donald M.

1997-01-01

This paper introduces a dual active load path fail-safe fatigue design concept analyzed by Monte Carlo simulation. The concept utilizes the inherent fatigue life differences between selected pairs of components for an active dual path system, enhanced by a stress level bias in one component. The design is applied to a baseline design; a safe life fatigue problem studied in an American Helicopter Society (AHS) round robin. The dual active path design is compared with a two-element standby fail-safe system and the baseline design for life at specified reliability levels and weight. The sensitivity of life estimates for both the baseline and fail-safe designs was examined by considering normal and Weibull distribution laws and coefficient of variation levels. Results showed that the biased dual path system lifetimes, for both the first element failure and residual life, were much greater than for standby systems. The sensitivity of the residual life-weight relationship was not excessive at reliability levels up to R = 0.9999 and the weight penalty was small. The sensitivity of life estimates increases dramatically at higher reliability levels.

Alcohol and drug treatment involvement, 12-step attendance and abstinence: 9-year cross-lagged analysis of adults in an integrated health plan.

PubMed

Witbrodt, Jane; Ye, Yu; Bond, Jason; Chi, Felicia; Weisner, Constance; Mertens, Jennifer

2014-04-01

This study explored causal relationships between post-treatment 12-step attendance and abstinence at multiple data waves and examined indirect paths leading from treatment initiation to abstinence 9-years later. Adults (N = 1945) seeking help for alcohol or drug use disorders from integrated healthcare organization outpatient treatment programs were followed at 1-, 5-, 7- and 9-years. Path modeling with cross-lagged partial regression coefficients was used to test causal relationships. Cross-lagged paths indicated greater 12-step attendance during years 1 and 5 and were casually related to past-30-day abstinence at years 5 and 7 respectfully, suggesting 12-step attendance leads to abstinence (but not vice versa) well into the post-treatment period. Some gender differences were found in these relationships. Three significant time-lagged, indirect paths emerged linking treatment duration to year-9 abstinence. Conclusions are discussed in the context of other studies using longitudinal designs. For outpatient clients, results reinforce the value of lengthier treatment duration and 12-step attendance in year 1. Copyright © 2014 Elsevier Inc. All rights reserved.

Multigroup Path Analysis of the Influence of Healthcare Quality, by Different Health Insurance Types.

PubMed

Hong, Yong-Rock; Holcomb, Derek; Ballard, Michael; Schwartz, Laurel

Winds of change have been blowing in the U.S. healthcare system since passage of the Affordable Care Act. Examining differences between individuals covered by different types of insurance is essential if healthcare executives are to develop new strategies in response to the emerging health insurance market. In this study, we used multigroup path analysis models to examine the moderating effects of health insurance on direct and indirect associations with general health status, satisfaction with received care, financial burden, and perceived value of the healthcare system. Data were obtained from the 2012 Medical Expenditure Panel Survey and analyzed according to the types of insurance: private, public, and military. With the satisfactory fit of the model (χ = 2,532.644, df = 96, p < .001; normed fit index = 0.943; incremental fit index = 0.945; comparative fit index = 0.957; root mean squared error of approximation = 0.044), higher healthcare quality was positively associated with better health status, greater satisfaction, and greater perceived value of the healthcare system in the three insurance groups. In addition, although all direct paths between health service quality and financial burden were not statistically significant, indirect effects were significant in all models through health status. Being married and earning higher incomes were also found to be strong predictors of better health status and health service quality. Efforts to improve the quality of health services are needed, which could contribute to a reduction in health disparities among insurance beneficiaries and result in less healthcare spending.

Multiple paths of electron flow to current in microbial electrolysis cells fed with low and high concentrations of propionate.

PubMed

Hari, Ananda Rao; Katuri, Krishna P; Gorron, Eduardo; Logan, Bruce E; Saikaly, Pascal E

2016-07-01

Microbial electrolysis cells (MECs) provide a viable approach for bioenergy generation from fermentable substrates such as propionate. However, the paths of electron flow during propionate oxidation in the anode of MECs are unknown. Here, the paths of electron flow involved in propionate oxidation in the anode of two-chambered MECs were examined at low (4.5 mM) and high (36 mM) propionate concentrations. Electron mass balances and microbial community analysis revealed that multiple paths of electron flow (via acetate/H2 or acetate/formate) to current could occur simultaneously during propionate oxidation regardless of the concentration tested. Current (57-96 %) was the largest electron sink and methane (0-2.3 %) production was relatively unimportant at both concentrations based on electron balances. At a low propionate concentration, reactors supplemented with 2-bromoethanesulfonate had slightly higher coulombic efficiencies than reactors lacking this methanogenesis inhibitor. However, an opposite trend was observed at high propionate concentration, where reactors supplemented with 2-bromoethanesulfonate had a lower coulombic efficiency and there was a greater percentage of electron loss (23.5 %) to undefined sinks compared to reactors without 2-bromoethanesulfonate (11.2 %). Propionate removal efficiencies were 98 % (low propionate concentration) and 78 % (high propionate concentration). Analysis of 16S rRNA gene pyrosequencing revealed the dominance of sequences most similar to Geobacter sulfurreducens PCA and G. sulfurreducens subsp. ethanolicus. Collectively, these results provide new insights on the paths of electron flow during propionate oxidation in the anode of MECs fed with low and high propionate concentrations.

Conscientious personality and young drivers’ crash risk

PubMed Central

Ehsani, Johnathon P.; Li, Kaigang; Simons-Morton, Bruce; Tree-McGrath, Cheyenne Fox; Perlus, Jessamyn; O’Brien, Fearghal; Klauer, Sheila G.

2015-01-01

Introduction Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior and crashes and near-crashes, using naturalistic driving research methods. Method Participants’ driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes and near-crashes (CNC) were assessed over the first 18 months of licensure using naturalistic driving methods. A personality survey (NEO-Five Factor Inventory) was administered at baseline. The association between personality characteristics, KRD rate, secondary task engagement rate and CNC rate was estimated using a linear regression model. Mediation analysis was conducted to examine if participants’ KRD rate or secondary task engagement rate mediated the relationship between personality and CNC. Data were collected as part of the Naturalistic Teen Driving Study. Results Conscientiousness was marginally negatively associated with CNC (path c = −0.034, p = .09) and both potential mediators KRD (path a = −0.040, p = .09) and secondary task engagement while driving (path a = −0.053, p = .03). KRD, but not secondary task engagement, was found to mediate (path b = 0.376, p = .02) the relationship between conscientiousness and CNC (path c’ = −0.025, p = .20). Conclusions Using objective measures of driving behavior and a widely used personality construct, these findings present a causal pathway through which personality and risky driving are associated with CNC. Specifically, more conscientious teenage drivers engaged in fewer risky driving maneuvers, suffered fewer CNC. Practical Applications Part of the variability in crash-risk observed among newly licensed teenage drivers can be explained by personality. Parents and driving instructors may take teenage drivers’ personality into account when providing guidance, and establishing norms and expectations about driving. PMID:26403906

Conscientious personality and young drivers' crash risk.

PubMed

Ehsani, Johnathon P; Li, Kaigang; Simons-Morton, Bruce G; Fox Tree-McGrath, Cheyenne; Perlus, Jessamyn G; O'Brien, Fearghal; Klauer, Sheila G

2015-09-01

Personality characteristics are associated with many risk behaviors. However, the relationship between personality traits, risky driving behavior, and crash risk is poorly understood. The purpose of this study was to examine the association between personality, risky driving behavior, and crashes and near-crashes, using naturalistic driving research methods. Participants' driving exposure, kinematic risky driving (KRD), high-risk secondary task engagement, and the frequency of crashes and near-crashes (CNC) were assessed over the first 18months of licensure using naturalistic driving methods. A personality survey (NEO-Five Factor Inventory) was administered at baseline. The association between personality characteristics, KRD rate, secondary task engagement rate, and CNC rate was estimated using a linear regression model. Mediation analysis was conducted to examine if participants' KRD rate or secondary task engagement rate mediated the relationship between personality and CNC. Data were collected as part of the Naturalistic Teen Driving Study. Conscientiousness was marginally negatively associated with CNC (path c=-0.034, p=.09) and both potential mediators KRD (path a=-0.040, p=.09) and secondary task engagement while driving (path a=-0.053, p=.03). KRD, but not secondary task engagement, was found to mediate (path b=0.376, p=.02) the relationship between conscientiousness and CNC (path c'=-0.025, p=.20). Using objective measures of driving behavior and a widely used personality construct, these findings present a causal pathway through which personality and risky driving are associated with CNC. Specifically, more conscientious teenage drivers engaged in fewer risky driving maneuvers, and suffered fewer CNC. Part of the variability in crash risk observed among newly licensed teenage drivers can be explained by personality. Parents and driving instructors may take teenage drivers' personality into account when providing guidance, and establishing norms and expectations about driving. Published by Elsevier Ltd.

A Model Linking Diverse Women's Child Sexual Abuse History with Sexual Risk Taking

ERIC Educational Resources Information Center

Watson, Laurel B.; Matheny, Kenneth B.; Gagne, Phill; Brack, Greg; Ancis, Julie R.

2013-01-01

The purpose of our study was to examine the role that child sexual abuse may play in body surveillance and sexual risk behaviors among undergraduate women. First, a measured variable path analysis was conducted, which assessed the relations among a history of child sexual abuse, body surveillance, and sexual risk behaviors. Furthermore, body…

GIS and path analysis: examining associations between the birds, the bees, and plant sex in Echinocereus coccineus (Cactaceae)

Treesearch

Summer Scobell; Stewart Schultz

2005-01-01

We tested hypotheses of how pollinators and water resource gradients influence the evolution of dioecy using Echinocereus coccineus, a cactus with both hermaphroditic and dioecious populations growing over wide climatic and biotic gradients in the Madrean Archipelago. A GIS database was compiled from herbarium specimens, rainfall data, and...

Suicidal or Self-Harming Ideation in Military Personnel Transitioning to Civilian Life

ERIC Educational Resources Information Center

Mansfield, Alyssa J.; Bender, Randall H.; Hourani, Laurel L.; Larson, Gerald E.

2011-01-01

Suicides have markedly increased among military personnel in recent years. We used path analysis to examine factors associated with suicidal/self-harming ideation among male Navy and Marine Corps personnel transitioning to civilian life. Roughly 7% of men (Sailors = 5.3%, Marines = 9.0%) reported ideation during the previous 30 days. Results…

Varsity Sport Participation and Consumption as Two of Several Factors Associated with College Achievement and Attrition.

ERIC Educational Resources Information Center

Henriksen, Larry; And Others

The study reported in this paper used path analysis statistical methodology and an attrition model to examine the separate and combined relationships of several different types of background, personal, and college experience variables with the attained college grade-point average (GPA) and graduation rate for 3,125 Ball State (Indiana) University…

Perceptions of Retirement Affect Career Commitment: The Mediating Role of Retirement System Satisfaction for Two Teacher Age Groups

ERIC Educational Resources Information Center

Smith, Justin L.; Conley, Sharon; You, Sukkyung

2015-01-01

This study investigated a sample of California elementary, intermediate, and high school employed teachers (N = 247) to assess the effects of retirement perceptions on career commitment among teachers who are in different age groupings. Using path analysis, the influence of five retirement perceptions variables was examined: concerns about…

The Relationship between Smoker Role Models and Intentions to Smoke among Adolescents

ERIC Educational Resources Information Center

Wiium, Nora; Breivik, Kyrre; Wold, Bente

2006-01-01

The study examines how adolescents' perceptions of exposure to smoker role models relate to their intentions to smoke, both directly, and indirectly through attitudes, norms, and perceived behavioural control. The data is based on a national representative sample of 15-year-olds (n=1670) in Norway. Path analysis indicates that perceptions of model…

Path Analysis on the Factors Influencing Learning Outcome for Hospitality Interns--From the Flow Theory Perspective

ERIC Educational Resources Information Center

Wang, Shu-Tai; Chen, Cheng-Chung

2015-01-01

Learning outcome is an important indicator for educators in evaluating curriculum design. The focus of this study has been to examine the factors within internship programs, recognizing the complex nature of knowledge application in a practical industry environment. Flow theory was adopted to explain the psychological state of hospitality students…

Body Image and Eating Disorder Symptoms in Sexual Minority Men: A Test and Extension of Objectification Theory

ERIC Educational Resources Information Center

Wiseman, Marcie C.; Moradi, Bonnie

2010-01-01

On the basis of integrating objectification theory research with research on body image and eating problems among sexual minority men, the present study examined relations among sociocultural and psychological correlates of eating disorder symptoms with a sample of 231 sexual minority men. Results of a path analysis supported tenets of…

Developments in the application of the geometrical theory of diffraction and computer graphics to aircraft inter-antenna coupling analysis

NASA Astrophysics Data System (ADS)

Bogusz, Michael

1993-01-01

The need for a systematic methodology for the analysis of aircraft electromagnetic compatibility (EMC) problems is examined. The available computer aids used in aircraft EMC analysis are assessed and a theoretical basis is established for the complex algorithms which identify and quantify electromagnetic interactions. An overview is presented of one particularly well established aircraft antenna to antenna EMC analysis code, the Aircraft Inter-Antenna Propagation with Graphics (AAPG) Version 07 software. The specific new algorithms created to compute cone geodesics and their associated path losses and to graph the physical coupling path are discussed. These algorithms are validated against basic principles. Loss computations apply the uniform geometrical theory of diffraction and are subsequently compared to measurement data. The increased modelling and analysis capabilities of the newly developed AAPG Version 09 are compared to those of Version 07. Several models of real aircraft, namely the Electronic Systems Trainer Challenger, are generated and provided as a basis for this preliminary comparative assessment. Issues such as software reliability, algorithm stability, and quality of hardcopy output are also discussed.

Shock and Rarefaction Waves in a Heterogeneous Mantle

NASA Astrophysics Data System (ADS)

Jordan, J.; Hesse, M. A.

2012-12-01

We explore the effect of heterogeneities on partial melting and melt migration during active upwelling in the Earth's mantle. We have constructed simple, explicit nonlinear models in one dimension to examine heterogeneity and its dynamic affects on porosity, temperature and the magnesium number in a partially molten, porous medium comprised of olivine. The composition of the melt and solid are defined by a closed, binary phase diagram for a simplified, two-component olivine system. The two-component solid solution is represented by a phase loop where concentrations 0 and 1 to correspond to fayalite and forsterite, respectively. For analysis, we examine an advective system with a Riemann initial condition. Chromatographic tools and theory have primarily been used to track large, rare earth elements as tracers. In our case, we employ these theoretical tools to highlight the importance of the magnesium number, enthalpy and overall heterogeneity in the dynamics of melt migration. We calculate the eigenvectors and eigenvalues in the concentration-enthalpy space in order to glean the characteristics of the waves emerging the Riemann step. Analysis on Riemann problems of this nature shows us that the composition-enthalpy waves can be represented by self-similar solutions. The eigenvalues of the composition-enthalpy system represent the characteristic wave propagation speeds of the compositions and enthalpy through the domain. Furthermore, the corresponding eigenvectors are the directions of variation, or ``pathways," in concentration-enthalpy space that the characteristic waves follow. In the two-component system, the Riemann problem yields two waves connected by an intermediate concentration-enthalpy state determined by the intersections of the integral curves of the eigenvectors emanating from both the initial and boundary states. The first wave, ``slow path," and second wave, ``fast path," follow the aformentioned pathways set by the eigenvectors. The slow path wave has a zero eigenvalue, corresponding to a wave speed of zero, which preserves a residual imprint of the initial condition. Freezing fronts textemdash those that result in a negative change in porositytextemdash feature fast path waves that travel as shocks, whereas the fast path waves of melting fronts travel as spreading, rarefaction waves.

Are socioeconomic disparities in health behavior mediated by differential media use? Test of the communication inequality theory.

PubMed

Ishikawa, Yoshiki; Kondo, Naoki; Kawachi, Ichiro; Viswanath, Kasisomayajula

2016-11-01

Communication inequality has been offered as one potential mechanism through which social determinants influence multiple health behaviors. The purpose of this study was to examine the underlying mechanisms between communication inequality and health behaviors. Data from a nationally representative cross-sectional survey of 18,426 people aged 18 years and above in the United States were used for secondary analysis. Measures included socio-demographic characteristics, social participation (structural social capital), health media use (TV, print, and the Internet), and five health behaviors (physical activity, cigarette smoking, alcohol use, and intake of fruit and vegetable). Path analysis was performed to examine the linkages between social determinants, health media use, social participation, and social gradients in health behaviors. Path analysis revealed that socioeconomic gradients in health behaviors is mediated by: 1) inequalities in health media use; 2) disparities in social participation, which leads to differential media use; and 3) disparities in social participation that are not mediated by media use. Consistent with the theory of communication inequality, socioeconomic disparities in media use partially mediate disparities in multiple health behaviors. To address health inequalities, it is important to utilize health media to target populations with low socioeconomic statuses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

VLF Signal Anomalies during the Earthquacke preparation phase

NASA Astrophysics Data System (ADS)

NAIT Amor, S.; Omari, T.

2016-12-01

In this contribution we will present a new results on the VLF signal anomalies related to the earthquacke. The technic of the Sun Rise Terminator (SRT) effect is adopted. The importance of this study is that the earthquack center was at 50 km from the receiver allowing the analysis of many Transmitters to receiver paths. Our resullts show that the SRT moved toward nightimte a days before the earthquacke. We also examined the time difference between two successive SRT observed on NAA-Algiers path where one correspond to the terminator passage through the receiver region and the second far from it which can be used as a reference. The SRT time difference results confirmed the SRT displacement.

Second-Guessing Scientists and Engineers: Post Hoc Criticism and the Reform of Practice in Green Chemistry and Engineering.

PubMed

Lynch, William T

2015-10-01

The article examines and extends work bringing together engineering ethics and Science and Technology Studies, which had built upon Diane Vaughan's analysis of the Challenger shuttle accident as a test case. Reconsidering the use of her term "normalization of deviance," the article argues for a middle path between moralizing against and excusing away engineering practices contributing to engineering disaster. To explore an illustrative pedagogical case and to suggest avenues for constructive research developing this middle path, it examines the emergence of green chemistry and green engineering. Green chemistry began when Paul Anastas and John Warner developed a set of new rules for chemical synthesis that sought to learn from missed opportunities to avoid environmental damage in the twentieth century, an approach that was soon extended to engineering as well. Examination of tacit assumptions about historical counterfactuals in recent, interdisciplinary discussions of green chemistry illuminate competing views about the field's prospects. An integrated perspective is sought, addressing how both technical practice within chemistry and engineering and the influence of a wider "social movement" can play a role in remedying environmental problems.

Investigation of progressive failure robustness and alternate load paths for damage tolerant structures

NASA Astrophysics Data System (ADS)

Marhadi, Kun Saptohartyadi

Structural optimization for damage tolerance under various unforeseen damage scenarios is computationally challenging. It couples non-linear progressive failure analysis with sampling-based stochastic analysis of random damage. The goal of this research was to understand the relationship between alternate load paths available in a structure and its damage tolerance, and to use this information to develop computationally efficient methods for designing damage tolerant structures. Progressive failure of a redundant truss structure subjected to small random variability was investigated to identify features that correlate with robustness and predictability of the structure's progressive failure. The identified features were used to develop numerical surrogate measures that permit computationally efficient deterministic optimization to achieve robustness and predictability of progressive failure. Analysis of damage tolerance on designs with robust progressive failure indicated that robustness and predictability of progressive failure do not guarantee damage tolerance. Damage tolerance requires a structure to redistribute its load to alternate load paths. In order to investigate the load distribution characteristics that lead to damage tolerance in structures, designs with varying degrees of damage tolerance were generated using brute force stochastic optimization. A method based on principal component analysis was used to describe load distributions (alternate load paths) in the structures. Results indicate that a structure that can develop alternate paths is not necessarily damage tolerant. The alternate load paths must have a required minimum load capability. Robustness analysis of damage tolerant optimum designs indicates that designs are tailored to specified damage. A design Optimized under one damage specification can be sensitive to other damages not considered. Effectiveness of existing load path definitions and characterizations were investigated for continuum structures. A load path definition using a relative compliance change measure (U* field) was demonstrated to be the most useful measure of load path. This measure provides quantitative information on load path trajectories and qualitative information on the effectiveness of the load path. The use of the U* description of load paths in optimizing structures for effective load paths was investigated.

MEGASTAR: The meaning of growth. An assessment of systems, technologies, and requirements. [methodology for display and analysis of energy production and consumption

NASA Technical Reports Server (NTRS)

1974-01-01

A methodology for the display and analysis of postulated energy futures for the United States is presented. A systems approach methodology including the methodology of technology assessment is used to examine three energy scenarios--the Westinghouse Nuclear Electric Economy, the Ford Technical Fix Base Case and a MEGASTAR generated Alternate to the Ford Technical Fix Base Case. The three scenarios represent different paths of energy consumption from the present to the year 2000. Associated with these paths are various mixes of fuels, conversion, distribution, conservation and end-use technologies. MEGASTAR presents the estimated times and unit requirements to supply the fuels, conversion and distribution systems for the postulated end uses for the three scenarios and then estimates the aggregate manpower, materials, and capital requirements needed to develop the energy system described by the particular scenario.

Social Cognitive Model of College Satisfaction: A Test of Measurement and Path Models

ERIC Educational Resources Information Center

Feldt, Ronald C.

2012-01-01

The study examined a model that integrates social-cognitive and trait-personality constructs to examine two domains of college satisfaction. Direct and indirect effects were observed for conscientiousness, perception of institutional resources, self-efficacy, and goal progress. Paths differed for personal and institutional satisfaction. Most…

Cognitive and affective mechanisms of pain and fatigue in multiple sclerosis.

PubMed

Arewasikporn, Anne; Turner, Aaron P; Alschuler, Kevin N; Hughes, Abbey J; Ehde, Dawn M

2018-06-01

To examine the extent to which pain catastrophizing, fatigue catastrophizing, positive affect, and negative affect simultaneously mediated the associations between common symptoms of multiple sclerosis (MS; i.e., pain, fatigue) and impact on daily life, depressive symptoms, and resilience. Participants were community-dwelling adults with MS (N = 163) reporting chronic pain, fatigue, and/or moderate depressive symptoms. Multiple mediation path analysis was used to model potential mediators of pain and fatigue separately, using baseline data from a randomized controlled trial comparing two symptom self-management interventions. In the pain model, pain catastrophizing was a mediator of pain intensity with pain interference and depression. Negative affect was a mediator of pain intensity with depression and resilience. In the fatigue model, fatigue catastrophizing was a mediator of fatigue intensity with fatigue impact and depression. Positive affect was a mediator of fatigue intensity with depression and resilience. These findings provide preliminary support for the presence of differential effects of cognitive-affective mediators and suggest potential targets for psychological interventions based on an individual's clinical presentation. The differential mediating effects also support the inclusion of both positive and negative aspects of psychological health in models of pain and fatigue, which would not be otherwise apparent if negative constructs were examined in isolation. To our knowledge, this is the first study to utilize a multivariate path analysis approach to examine cognitive-affective mediators of pain and fatigue in MS, while also examining positive and negative constructs concurrently. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Does It Matter What You Call It? The Relationship Between Labeling Unwanted Sexual Experiences and Distress

ERIC Educational Resources Information Center

Harned, Melanie S.

2004-01-01

Using cross-sectional data from 2 samples of women attending a university (N = 1,395), the author examined the relationship among women's labeling of their unwanted sexual experiences (USEs) with dating partners and a variety of psychological and school-related outcomes. Three competing path analysis models were tested to determine whether the…

Spanking and Child Development during the First 5 Years of Life

ERIC Educational Resources Information Center

Maguire-Jack, Kathryn; Gromoske, Andrea N.; Berger, Lawrence M.

2012-01-01

Using data from the Fragile Families and Child Wellbeing Study (N = 3,870) and cross-lagged path analysis, the authors examined whether spanking at ages 1 and 3 is adversely associated with cognitive skills and behavior problems at ages 3 and 5. The authors found spanking at age 1 was associated with a higher level of spanking and externalizing…

Characteristic Reading Problems of Adult Illiterates. Report Number 3. Summary Reports of Paths to Literacy and Illiteracy in Newfoundland and Labrador.

ERIC Educational Resources Information Center

Beebe, Mona

A study examined the reading problems of adults in Newfoundland (Canada) with low reading ability. It explored the genesis of these problems through a retrospective analysis of their lives as school children; and determined the relationship between literacy development and personal background factors, school factors, physiological factors, and…

Gender-Based Salary Inequity in Social Work: Mediators of Gender's Effect on Salary

ERIC Educational Resources Information Center

Koeske, Gary F.; Krowinski, William J.

2004-01-01

This study examined the direct effect of gender, controlling for years of experience, job role, and other variables, in a sample of 359 Pennsylvania social workers. Men social workers received significantly more yearly salary (an estimated $3,665 more) than women social workers. A path analysis suggested that the salary advantage for men that was…

Models of Traumatic Experiences and Children's Psychological Adjustment: The Roles of Perceived Parenting and the Children's Own Resources and Activity.

ERIC Educational Resources Information Center

Punamaki, Raija-Leena; Qouta, Samir; El Sarraj, Eyad

1997-01-01

Used path analysis to examine relations between trauma, perceived parenting, resources, political activity, and adjustment in Palestinian 11- and 12-year olds. Found that the more trauma experienced, the more negative parenting the children experienced, the more political activity they showed, and the more they suffered from adjustment problems.…

Watershed features and stream water quality: Gaining insight through path analysis in a Midwest urban landscape, USA

Treesearch

Jiayu Wu; Timothy W. Stewart; Janette R. Thompson; Randy Kolka; Kristie J. Franz

2015-01-01

Urban stream condition is often degraded by human activities in the surrounding watershed. Given the complexity of urban areas, relationships among variables that cause stream degradation can be difficult to isolate. We examined factors affecting stream condition by evaluating social, terrestrial, stream hydrology and water quality variables from 20 urban stream...

Pathways to the Principalship: An Event History Analysis of the Careers of Teachers with Principal Certification

ERIC Educational Resources Information Center

Davis, Bradley W.; Gooden, Mark A.; Bowers, Alex J.

2017-01-01

Utilizing rich data on nearly 11,000 educators over 17 academic years in a highly diverse context, we examine the career paths of teachers to determine whether and when they transition into the principalship. We utilize a variety of event history analyses, including discrete-time hazard modeling, to determine how an individual's race, gender, and…

Examining the Relationship between Middle School Students' Critical Reading Skills, Science Literacy Skills and Attitudes: A Structural Equation Modeling

ERIC Educational Resources Information Center

Karademir, Ersin; Ulucinar, Ufuk

2017-01-01

The purpose of this study is to verify the causal relationship between middle school students' critical reading skills, science literacy skills and attitudes towards science literacy with research data according to the default model. Through the structural equation modeling, path analysis has been applied in the study which was designed in…

Videotex in Education: Current Developments in Screen Design, Data Structure, and Access Control.

ERIC Educational Resources Information Center

Kerr, Stephen T.

This four-section paper begins with a brief description of videotex and the paths its development has followed during its short lifespan. The second section examines how videotex systems should present and display information, and how such information should be internally organized so that it is maximally useful for the reader/user. The analysis,…

A Path Analysis of Pre-Service Teachers' Attitudes to Computer Use: Applying and Extending the Technology Acceptance Model in an Educational Context

ERIC Educational Resources Information Center

Teo, Timothy

2010-01-01

The purpose of this study is to examine pre-service teachers' attitudes to computers. This study extends the technology acceptance model (TAM) framework by adding subjective norm, facilitating conditions, and technological complexity as external variables. Results show that the TAM and subjective norm, facilitating conditions, and technological…

User Acceptance of Mobile Technology: A Campus-Wide Implementation of Blackboard's Mobile™ Learn Application

ERIC Educational Resources Information Center

Chen, Baiyun; Sivo, Stephen; Seilhamer, Ryan; Sugar, Amy; Mao, Jin

2013-01-01

Mobile learning is a fast growing trend in higher education. This study examined how an extended technology acceptance model (TAM) could evaluate and predict the use of a mobile application in learning. A path analysis design was used to measure the mediating effects on the use of Blackboard's Mobile™ Learn application in coursework (N = 77). The…

The Role of Youth Anger in Explaining Links between Parenting and Early Adolescent Prosocial and Antisocial Behavior

ERIC Educational Resources Information Center

Houltberg, Benjamin J.; Sheffield Morris, Amanda; Cui, Lixian; Henry, Carolyn S.; Criss, Michael M.

2016-01-01

The purpose of the current investigation was to examine the role of youth anger regulation and reactivity in the link between parenting and social adjustment among a sample of 84 youth residing in disadvantaged neighborhoods in a mid-southwestern city. Using path analysis, findings indicate that parents' responsive and discipline-related behaviors…

Numerical analysis of fundamental characteristics of superconducting magnetic bearings for a polarization modulator

NASA Astrophysics Data System (ADS)

Terachi, Yusuke; Terao, Yutaka; Ohsaki, Hiroyuki; Sakurai, Yuki; Matsumura, Tomotake; Sugai, Hajime; Utsunomiya, Shin; Kataza, Hirokazu; Yamamoto, Ryo

2017-07-01

We have carried out numerical analysis of mechanical properties of a superconducting magnetic bearing (SMB). A contactless bearing operating at below 10 K with low rotational energy loss is an attractive feature to be used as a rotational mechanism of a polarization modulator for a cosmic microwave background experiment. In such application, a rotor diameter of about 400 mm forces us to employ a segmented magnet. As a result, there is inevitable spatial gap between the segments. In order to understand the path towards the design optimizations, 2D and 3D FEM analyses were carried out to examine fundamental characteristics of the SMBs for a polarization modulator. Two axial flux type SMBs were dealt with in the analysis: (a) the SMB with axially magnetized permanent magnets (PMs), and (b) the SMB with radially magnetized PMs and steel components for magnetic flux paths. Magnetic flux lines and density distributions, electromagnetic force characteristics, spring constants, etc. were compared among some variations of the SMBs. From the numerical analysis results, it is discussed what type, configuration and design of SMBs are more suitable for a polarization modulator.

Understanding Associations Between Neighborhood Socioeconomic Status and Negative Consequences of Drinking: a Moderated Mediation Analysis.

PubMed

Karriker-Jaffe, Katherine J; Liu, HuiGuo; Kaplan, Lauren M

2016-05-01

We explored how neighborhood socioeconomic status (SES) is related to negative consequences of drinking to explain why racial/ethnic minority group members are more at risk than Whites for adverse alcohol outcomes. We tested direct and indirect effects of neighborhood SES on alcohol problems and examined differences by gender and race. We used data from the 2000 and 2005 National Alcohol Surveys (N = 7912 drinkers aged 18 and older; 49 % female) linked with data from the 2000 Decennial Census in multivariate path models adjusting for individual demographics. In the full sample, neighborhood disadvantage had a significant direct path to increased negative consequences, with no indirect paths through depression, positive affect or pro-drinking attitudes. Neighborhood affluence had significant indirect paths to increased negative consequences through greater pro-drinking attitudes and increased heavy drinking. Subgroup analyses showed the indirect path from affluence to consequences held for White men, with no effects of neighborhood disadvantage. For racial/ethnic minority men, significant indirect paths emerged from both neighborhood disadvantage and affluence to increased consequences through greater pro-drinking attitudes and more heavy drinking. For minority women, there was an indirect effect of neighborhood affluence through reduced depression to fewer drinking consequences. There were limited neighborhood effects on alcohol outcomes for White women. Interventions targeting pro-drinking attitudes in both affluent and disadvantaged areas may help reduce alcohol-related problems among men. Initiatives to improve neighborhood conditions could enhance mental health of minority women and reduce alcohol-related health disparities.

The structure of the UPPS-R-Child impulsivity scale and its relations with substance use outcomes among treatment-seeking adolescents.

PubMed

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.

The Structure of the UPPS-R-Child Impulsivity Scale and its Relations with Substance Use Outcomes Among Treatment-Seeking Adolescents

PubMed Central

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

Variations of Solar Non-axisymmetric Activity

NASA Astrophysics Data System (ADS)

Gyenge, N.; Baranyi, T.; Ludmány, A.

The temporal behaviour of solar active longitudes has been examined by using two sunspot catalogues, the Greenwich Photoheliographic Results (GPR) and the Debrecen Photoheliographic Data (DPD). The time-longitude diagrams of the activity distribution reveal the preferred longitudinal zones and their migration with respect to the Carrington frame. The migration paths outline a set of patterns in which the activity zone has alternating prograde/retrograde angular velocities with respect to the Carrington rotation rate. The time profiles of these variations can be described by a set of successive parabolae. Two similar migration paths have been selected from these datasets, one northern path during cycles 21 - 22 and one southern path during cycles 13 - 14, for closer examination and comparison of their dynamical behaviours. The rates of sunspot emergence exhibited in both migration paths similar periodicities, close to 1.3 years. This behaviour may imply that the active longitude is connected to the bottom of convection zone.

Path Dependence and Universal Health Coverage: The Case of Egypt

PubMed Central

Fouda, Ayman; Paolucci, Francesco

2017-01-01

Universal health coverage (UHC) is the big objective in health policy which several countries are seeking to achieve. Egypt is no different and its endeavors to attain UHC have been going on since the 1960s. This article discusses the status of UHC in Egypt using theories of political science and economics by analyzing the historical transformations in the Egyptian health system and its institutional settings. This article then specifically examines the path dependence theory against the sociopolitical background of Egypt and assesses any pattern between the theory and the current UHC status in Egypt. The important finding of this analysis is that the health policies and reforms in Egypt have been significantly influenced and limited by its historical institutional structure and development. Both the health policies and the institutional settings adopted a dependent path that limited Egypt’s endeavors to achieve the universal coverage. This dependent path also yielded many of the present-day challenges as in the weaknesses of the healthcare financing system and the inability to extend health coverage to the poor and the informal sector. These challenges subsequently had a negative impact on the accessibility of the healthcare services. PMID:29276704

Longitudinal associations between resilience and quality of life in eating disorders.

PubMed

Calvete, Esther; Las Hayas, Carlota; Gómez Del Barrio, Andrés

2018-01-01

This study examined the longitudinal reciprocal associations between resilience factors, quality of life (QoL) domains, and symptoms of eating disorders (EDs). Hypotheses included predictive paths from resilience factors of "acceptance of self and life" and "personal competence" to increased QoL and predictive paths from previous levels of QoL to resilience. A total of 184 patients with EDs (mean age = 29.55, SD = 9.17, 94.8% women) completed measures of resilience, QoL, and EDs symptoms over three waves spaced six month apart. Hypotheses were tested by path analysis. Resilience factors predicted improvements in psychological health and social relationship domains of QoL and a reduction of ED symptoms over time. In addition, psychological health increased acceptance of self and life consistently over time, whereas physical health increased the competence component of resilience. The relationships between resilience factors and QoL are reciprocal, with several mediational paths. A spiral of recursive influences between resilience factors and QoL can take place in people with EDs. This possibility offers new perspectives to understanding the process of recovery in patients with ED. Copyright © 2017 Elsevier B.V. All rights reserved.

Generalized Path Analysis and Generalized Simultaneous Equations Model for Recursive Systems with Responses of Mixed Types

ERIC Educational Resources Information Center

Tsai, Tien-Lung; Shau, Wen-Yi; Hu, Fu-Chang

2006-01-01

This article generalizes linear path analysis (PA) and simultaneous equations models (SiEM) to deal with mixed responses of different types in a recursive or triangular system. An efficient instrumental variable (IV) method for estimating the structural coefficients of a 2-equation partially recursive generalized path analysis (GPA) model and…

Language Education and ELT Materials in Turkey from the Path Dependence Perspective

ERIC Educational Resources Information Center

Isik, Ali

2011-01-01

This paper examines the role of traditional language teaching methodology on the current language teaching methodology in Turkey from the Path Dependence Theory perspective. Path Dependence claims that the past continues shaping the present. Similarly, traditional approaches still shape foreign/second language education. Turkey has inherited a…

A structural model of stress, motivation, and academic performance in medical students.

PubMed

Park, Jangho; Chung, Seockhoon; An, Hoyoung; Park, Seungjin; Lee, Chul; Kim, Seong Yoon; Lee, Jae-Dam; Kim, Ki-Soo

2012-06-01

The purpose of the present study was 1) to identify factors that may influence academic stress in medical students and 2) to investigate the causal relationships among these variables with path analysis. One hundred sixty medical students participated in the present study. Psychological parameters were assessed with the Medical Stress Scale, Minnesota Multiphasic Personality Inventory, Hamilton Depression Scale, Beck Depression Inventory, and Academic Motivation Scale. Linear regression and path analysis were used to examine the relationships among variables. Significant correlations were noted between several factors and Medical Stress scores. Specifically, Hamilton Depression Scale scores (β=0.26, p=0.03) and amotivation (β=0.20, p=0.01) and extrinsically identified regulation (β=0.27, p<0.01) response categories on the Academic Motivation Scale had independent and significant influences on Medical Stress Scale scores. A path analysis model indicated that stress, motivation, and academic performance formed a triangular feedback loop. Moreover, depression was associated with both stress and motivation, and personality was associated with motivation. The triangular feedback-loop structure in the present study indicated that actions that promote motivation benefit from interventions against stress and depression. Moreover, stress management increases motivation in students. Therefore, strategies designed to reduce academic pressures in medical students should consider these factors. Additional studies should focus on the relationship between motivation and depression.

A Structural Model of Stress, Motivation, and Academic Performance in Medical Students

PubMed Central

Park, Jangho; An, Hoyoung; Park, Seungjin; Lee, Chul; Kim, Seong Yoon; Lee, Jae-Dam; Kim, Ki-Soo

2012-01-01

Objective The purpose of the present study was 1) to identify factors that may influence academic stress in medical students and 2) to investigate the causal relationships among these variables with path analysis. Methods One hundred sixty medical students participated in the present study. Psychological parameters were assessed with the Medical Stress Scale, Minnesota Multiphasic Personality Inventory, Hamilton Depression Scale, Beck Depression Inventory, and Academic Motivation Scale. Linear regression and path analysis were used to examine the relationships among variables. Results Significant correlations were noted between several factors and Medical Stress scores. Specifically, Hamilton Depression Scale scores (β=0.26, p=0.03) and amotivation (β=0.20, p=0.01) and extrinsically identified regulation (β=0.27, p<0.01) response categories on the Academic Motivation Scale had independent and significant influences on Medical Stress Scale scores. A path analysis model indicated that stress, motivation, and academic performance formed a triangular feedback loop. Moreover, depression was associated with both stress and motivation, and personality was associated with motivation. Conclusion The triangular feedback-loop structure in the present study indicated that actions that promote motivation benefit from interventions against stress and depression. Moreover, stress management increases motivation in students. Therefore, strategies designed to reduce academic pressures in medical students should consider these factors. Additional studies should focus on the relationship between motivation and depression. PMID:22707964

Quantum structural fluctuation in para-hydrogen clusters revealed by the variational path integral method

NASA Astrophysics Data System (ADS)

Miura, Shinichi

2018-03-01

In this paper, the ground state of para-hydrogen clusters for size regime N ≤ 40 has been studied by our variational path integral molecular dynamics method. Long molecular dynamics calculations have been performed to accurately evaluate ground state properties. The chemical potential of the hydrogen molecule is found to have a zigzag size dependence, indicating the magic number stability for the clusters of the size N = 13, 26, 29, 34, and 39. One-body density of the hydrogen molecule is demonstrated to have a structured profile, not a melted one. The observed magic number stability is examined using the inherent structure analysis. We also have developed a novel method combining our variational path integral hybrid Monte Carlo method with the replica exchange technique. We introduce replicas of the original system bridging from the structured to the melted cluster, which is realized by scaling the potential energy of the system. Using the enhanced sampling method, the clusters are demonstrated to have the structured density profile in the ground state.

Quantum structural fluctuation in para-hydrogen clusters revealed by the variational path integral method.

PubMed

Miura, Shinichi

2018-03-14

In this paper, the ground state of para-hydrogen clusters for size regime N ≤ 40 has been studied by our variational path integral molecular dynamics method. Long molecular dynamics calculations have been performed to accurately evaluate ground state properties. The chemical potential of the hydrogen molecule is found to have a zigzag size dependence, indicating the magic number stability for the clusters of the size N = 13, 26, 29, 34, and 39. One-body density of the hydrogen molecule is demonstrated to have a structured profile, not a melted one. The observed magic number stability is examined using the inherent structure analysis. We also have developed a novel method combining our variational path integral hybrid Monte Carlo method with the replica exchange technique. We introduce replicas of the original system bridging from the structured to the melted cluster, which is realized by scaling the potential energy of the system. Using the enhanced sampling method, the clusters are demonstrated to have the structured density profile in the ground state.

Protonospheric columnar electron content determination. I - Analysis.

NASA Technical Reports Server (NTRS)

Almeida, O. G.

1973-01-01

A combination of phase-path length difference and Faraday rotation angle data obtained from geostationary satellite transmissions is used to determine the integration constant necessary to convert phase-path length difference information into absolute values of total slant columnar electron content. The total content thus determined, which is the sum of the ionospheric and protonospheric contents, is measured with uncertainties about one order of magnitude smaller than the value of the protonospheric content. It is thus, in principle, possible to determine the latter by subtracting from the measurement the so-called 'Faraday content.' This idea, proposed by several authors in the past, is critically examined in the present paper. It is impossible to totally eliminate the ionospheric contribution to the measurements; however, it is shown that the degree of elimination depends on the type of distribution of the longitudinal component of the geomagnetic field along the path of observation. Satisfactory minimization of the ionospheric contribution can be accomplished only under certain geometries of observation.

Hippocampus and Retrosplenial Cortex Combine Path Integration Signals for Successful Navigation

PubMed Central

Erdem, Uğur M.; Ross, Robert S.; Brown, Thackery I.; Hasselmo, Michael E.; Stern, Chantal E.

2013-01-01

The current study used fMRI in humans to examine goal-directed navigation in an open field environment. We designed a task that required participants to encode survey-level spatial information and subsequently navigate to a goal location in either first person, third person, or survey perspectives. Critically, no distinguishing landmarks or goal location markers were present in the environment, thereby requiring participants to rely on path integration mechanisms for successful navigation. We focused our analysis on mechanisms related to navigation and mechanisms tracking linear distance to the goal location. Successful navigation required translation of encoded survey-level map information for orientation and implementation of a planned route to the goal. Our results demonstrate that successful first and third person navigation trials recruited the anterior hippocampus more than trials when the goal location was not successfully reached. When examining only successful trials, the retrosplenial and posterior parietal cortices were recruited for goal-directed navigation in both first person and third person perspectives. Unique to first person perspective navigation, the hippocampus was recruited to path integrate self-motion cues with location computations toward the goal location. Last, our results demonstrate that the hippocampus supports goal-directed navigation by actively tracking proximity to the goal throughout navigation. When using path integration mechanisms in first person and third person perspective navigation, the posterior hippocampus was more strongly recruited as participants approach the goal. These findings provide critical insight into the neural mechanisms by which we are able to use map-level representations of our environment to reach our navigational goals. PMID:24305826

Why managers should care about fairness: the effects of aggregate justice perceptions on organizational outcomes.

PubMed

Simons, Tony; Roberson, Quinetta

2003-06-01

This work examines the aggregation of justice perceptions to the departmental level and the business-unit level, the impact of these aggregate perceptions on business-unit-level outcomes, and the usefulness of the distinction between procedural and interpersonal justice at different levels of analysis. Latent variables analyses of individual-level and department-level data from 4,539 employees in 783 departments at 97 hotel properties showed that the 2 justice types exercise unique paths of impact on employees' organizational commitment and thus on turnover intentions and discretionary service behavior. Business-unit-level analyses further demonstrate paths of association between aggregate justice perceptions, aggregate commitment levels, and the business-unit-level outcomes of employee turnover rates and customer satisfaction ratings.

The contribution of personality and workplace characteristics in predicting turnover intention among sexual assault nurse examiners: a path analytic study.

PubMed

Strunk, Kathleen C; Strunk, Kamden K

2012-09-01

The purpose of this study was to determine how personality characteristics, sense of organizational empowerment, and job satisfaction combine to predict turnover intention among a population of Sexual Assault Nurse Examiners (SANEs). Data were collected from 161 SANEs from 23 SANE organizations across the central and west United States through standardized tools and a demographic questionnaire. Both personality, namely agreeableness and workplace characteristics, particularly perceived empowerment and job satisfaction, combine to predict intention to leave the job of these sampled SANEs. One particularly curious finding was the positive prediction of agreeableness on turnover intention - that is, more agreeable people would be more likely to leave their jobs as SANEs. Professionals can gain insight from the path analysis results that show the need to address both personal and organizational factors in mitigating turnover intention among SANEs. This appears to be particularly true in providing a sense of empowerment and opportunity within the organization. © 2012 International Association of Forensic Nurses.

Analytical transmissibility based transfer path analysis for multi-energy-domain systems using four-pole parameter theory

NASA Astrophysics Data System (ADS)

Mashayekhi, Mohammad Jalali; Behdinan, Kamran

2017-10-01

The increasing demand to minimize undesired vibration and noise levels in several high-tech industries has generated a renewed interest in vibration transfer path analysis. Analyzing vibration transfer paths within a system is of crucial importance in designing an effective vibration isolation strategy. Most of the existing vibration transfer path analysis techniques are empirical which are suitable for diagnosis and troubleshooting purpose. The lack of an analytical transfer path analysis to be used in the design stage is the main motivation behind this research. In this paper an analytical transfer path analysis based on the four-pole theory is proposed for multi-energy-domain systems. Bond graph modeling technique which is an effective approach to model multi-energy-domain systems is used to develop the system model. In this paper an electro-mechanical system is used as a benchmark example to elucidate the effectiveness of the proposed technique. An algorithm to obtain the equivalent four-pole representation of a dynamical systems based on the corresponding bond graph model is also presented in this paper.

Transitioning to a narrow path: the impact of fear of falling in older adults.

PubMed

Dunlap, Pamela; Perera, Subashan; VanSwearingen, Jessie M; Wert, David; Brach, Jennifer S

2012-01-01

Everyday ambulation requires navigation of variable terrain, transitions from wide to narrow pathways, and avoiding obstacles. While the effect of age on the transition to a narrow path has been examined briefly, little is known about the impact of fear of falling on gait during the transition to a narrow path. The purpose was to examine the effect of age and fear of falling on gait during transition to a narrow path. In 31 young, mean age=25.3 years, and 30 older adults, mean age=79.6 years, step length, step time, step width and gait speed were examined during usual and transition to narrow pathway using an instrumented walkway. During the transition to narrow walk condition, fearful older adults compared to young had a wider step width (0.06 m vs 0.04 m) prior to the narrow path and took shorter steps (0.53 m vs 0.72 m; p<0.001). Compared to non-fearful older adults, fearful older adults walked slower and took shorter steps during narrow path walking (gait speed: 1.1m/s vs 0.82 m/s; p=0.01; step length: 0.60 m vs 0.47 m; p=0.03). In young and non-fearful older adults narrow path gait was similar to usual gait. Whereas older adults who were fearful, walked slower (0.82 m/s vs 0.91 m/s; p=0.001) and took shorter steps (0.44 m vs 0.53 m; p=0.004) during narrow path walking compared to usual walking. Changes in gait characteristics with transitioning to a narrow pathway were greater for fear of falling than for age. Copyright © 2011 Elsevier B.V. All rights reserved.

Predictors of satisfaction in geographically close and long-distance relationships.

PubMed

Lee, Ji-yeon; Pistole, M Carole

2012-04-01

In this study, the authors examined geographically close (GCRs) and long-distance (LDRs) romantic relationship satisfaction as explained by insecure attachment, self-disclosure, gossip, and idealization. After college student participants (N = 536) completed a Web survey, structural equation modeling (SEM) multigroup analysis revealed that the GCR and LDR models were nonequivalent, as expected. Self-disclosure mediated the insecure attachment-idealization path differently in GCRs and in LDRs. Self-disclosure was positively associated with idealization in GCRs and negatively associated with idealization in LDRs, with the insecure attachment-idealization and the insecure attachment-satisfaction paths negative for both GCRs and LDRs. Furthermore, the insecure attachment-idealization path was stronger than the mediated path, especially for LDRs; the insecure attachment-satisfaction path was stronger than the mediation model for GCRs and LDRs. In other words, the GCR and LDR models differed despite some similarities. For both, with higher insecure (i.e., anxious and avoidant) attachment, the person discloses less to the partner, idealizes the partner less, and is less satisfied with the relationship. Also, people who idealize are more satisfied. In contrast, in LDRs only, with higher insecure attachment, the people tend to gossip more. With higher insecure attachment and with higher self-disclosure, people idealize more in GCRs but idealize less in LDRs. Overall, attachment insecurity explained more idealization and satisfaction in LDRs than in GCRs. Implications are discussed.

Interactive cutting path analysis programs

NASA Technical Reports Server (NTRS)

Weiner, J. M.; Williams, D. S.; Colley, S. R.

1975-01-01

The operation of numerically controlled machine tools is interactively simulated. Four programs were developed to graphically display the cutting paths for a Monarch lathe, Cintimatic mill, Strippit sheet metal punch, and the wiring path for a Standard wire wrap machine. These programs are run on a IMLAC PDS-ID graphic display system under the DOS-3 disk operating system. The cutting path analysis programs accept input via both paper tape and disk file.

Connections, Paths, and Explanations--A Social Network Approach to Investigating Experiences of Early Childhood Special Education with the ECLS-K

ERIC Educational Resources Information Center

Akers, Kathryn Shirley

2011-01-01

The purpose of this study is to demonstrate a practical application of social network analysis in the field of education using a large-scale data source. Using the Early Childhood Longitudinal Base Year data, a network is identified by examining the connections that occur between supports, both inside and outside formal special education resources…

A Comparative Test of Work-Family Conflict Models and Critical Examination of Work-Family Linkages

ERIC Educational Resources Information Center

Michel, Jesse S.; Mitchelson, Jacqueline K.; Kotrba, Lindsey M.; LeBreton, James M.; Baltes, Boris B.

2009-01-01

This paper is a comprehensive meta-analysis of over 20 years of work-family conflict research. A series of path analyses were conducted to compare and contrast existing work-family conflict models, as well as a new model we developed which integrates and synthesizes current work-family theory and research. This new model accounted for 40% of the…

The Pressure to Be Perfect: A Path Analysis Investigating the Effects of Institutional Resources on Self-Esteem and Engagement of Asian College Students

ERIC Educational Resources Information Center

Sahu, Subir

2012-01-01

This study researches the involvement and engagement of Asian college students in the United States. Utilizing Astin's Theory of Student Involvement, Tinto's Interactionalist Theory, and the Model Minority Stereotype as its theoretical foundation, this study examines if colleges and universities are truly engaging its Asian student…

Effects of Chinese Parental Practices on Adolescent School Outcomes Mediated by Conformity to Parents, Self-Esteem, and Self-Efficacy

ERIC Educational Resources Information Center

Shen, Yuh-Ling

2011-01-01

This study examines how the parental support and control affected school outcomes through conformity to parents, self-esteem, and self-efficacy in adolescence in Mainland China. The sample included 350 junior and senior high school students age ranging from 12 to 19 years, 48% of them were males. Using path model analysis, results showed that…

Roles of University Support for International Students in the United States: Analysis of a Systematic Model of University Identification, University Support, and Psychological Well-Being

ERIC Educational Resources Information Center

Cho, Jaehee; Yu, Hongsik

2015-01-01

Unlike previous research on international students' social support, this current study applied the concept of organizational support to university contexts, examining the effects of university support. Mainly based on the social identity/self-categorization stress model, this study developed and tested a path model composed of four key…

Satisfaction in multigenerational households.

PubMed

Mindel, C H; Wright, R

1982-07-01

Family life satisfaction can be seen and analyzed within a cost/reward exchange framework. Within this context satisfaction of the primary caregiver with living in a multigenerational household was examined for 99 Midwestern families. Important predictors of satisfaction were identified using path analysis. These predictors consisted of characteristics of the older person (in particular, indicators of dependency status, characteristics of the primary caregiver, and the situational problems of daily life).

Family Interactions, Exposure to Violence, and Emotion Regulation: Perceptions of Children and Early Adolescents at Risk

ERIC Educational Resources Information Center

Houltberg, Benjamin J.; Henry, Carolyn S.; Morris, Amanda Sheffield

2012-01-01

This study examined the protective nature of youth reports of family interactions in relation to perceived exposure to violence and anger regulation in 84 children and early adolescents (mean age of 10.5; 7-15 years old) primarily from ethnic minority groups and living in high-risk communities in a large southwestern city. Path analysis and…

The Relationship between Parental Involvement, Self-Regulated Learning, and Reading Achievement of Fifth Graders: A Path Analysis Using the ECLS-K Database

ERIC Educational Resources Information Center

Xu, Min; Kushner Benson, Susan N.; Mudrey-Camino, Renee; Steiner, Richard P.

2010-01-01

This study examined the relationship between parental involvement, self-regulated learning (SRL), and reading achievement through analyzing the fifth grade data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K). The results identified six dimensions of parental involvement that are likely to foster SRL of fifth…

Perceived discrimination and sexual precursor behaviors in Mexican American preadolescent girls: The role of psychological distress, sexual attitudes, and marianismo beliefs.

PubMed

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).

Influence of the Strain History on TWIP Steel Deformation Mechanisms in the Deep-Drawing Process

NASA Astrophysics Data System (ADS)

Lapovok, R.; Timokhina, I.; Mester, A.-K.; Weiss, M.; Shekhter, A.

2018-03-01

A study of preferable deformation modes on strain path and strain level in a TWIP steel sheet was performed. Different strain paths were obtained by stretch forming of specimens with various shapes and tensile tests. TEM analysis was performed on samples cut from various locations in the deformed specimens, which had different strain paths and strain levels and the preferable deformation modes were identified. Stresses caused by various strain paths were considered and an analytical analysis performed to identify the preferable deformation modes for the case of single crystal. For a single crystal, in assumption of the absence of lattice rotation, the strain path and the level of accumulated equivalent strain define the preferable deformation mode. For a polycrystalline material, such analytical analysis is not possible due to the large number of grains and, therefore, numerical simulation was employed. For the polycrystalline material, the role of strain path diminishes due to the presence of a large number of grains with random orientations and the effect of accumulated strain becomes dominant. However, at small strains the strain path still defines the level of twinning activity. TEM analysis experimentally confirmed that various deformation modes lead to different deformation strengthening mechanisms.

Influence of the Strain History on TWIP Steel Deformation Mechanisms in the Deep-Drawing Process

NASA Astrophysics Data System (ADS)

Lapovok, R.; Timokhina, I.; Mester, A.-K.; Weiss, M.; Shekhter, A.

2018-06-01

A study of preferable deformation modes on strain path and strain level in a TWIP steel sheet was performed. Different strain paths were obtained by stretch forming of specimens with various shapes and tensile tests. TEM analysis was performed on samples cut from various locations in the deformed specimens, which had different strain paths and strain levels and the preferable deformation modes were identified. Stresses caused by various strain paths were considered and an analytical analysis performed to identify the preferable deformation modes for the case of single crystal. For a single crystal, in assumption of the absence of lattice rotation, the strain path and the level of accumulated equivalent strain define the preferable deformation mode. For a polycrystalline material, such analytical analysis is not possible due to the large number of grains and, therefore, numerical simulation was employed. For the polycrystalline material, the role of strain path diminishes due to the presence of a large number of grains with random orientations and the effect of accumulated strain becomes dominant. However, at small strains the strain path still defines the level of twinning activity. TEM analysis experimentally confirmed that various deformation modes lead to different deformation strengthening mechanisms.

Social network analysis using k-Path centrality method

NASA Astrophysics Data System (ADS)

Taniarza, Natya; Adiwijaya; Maharani, Warih

2018-03-01

k-Path centrality is deemed as one of the effective methods to be applied in centrality measurement in which the influential node is estimated as the node that is being passed by information path frequently. Regarding this, k-Path centrality has been employed in the analysis of this paper specifically by adapting random-algorithm approach in order to: (1) determine the influential user’s ranking in a social media Twitter; and (2) ascertain the influence of parameter α in the numeration of k-Path centrality. According to the analysis, the findings showed that the method of k-Path centrality with random-algorithm approach can be used to determine user’s ranking which influences in the dissemination of information in Twitter. Furthermore, the findings also showed that parameter α influenced the duration and the ranking results: the less the α value, the longer the duration, yet the ranking results were more stable.

Testing Gender Effects on the Mechanisms Explaining the Association between Post-Traumatic Stress Symptoms and Substance Use Frequency

PubMed Central

Bornovalova, Marina A.; Ouimette, Paige; Crawford, Aaron V.; Levy, Roy

2009-01-01

The present study examines gender differences in the mechanisms that explain the association between PTSD symptoms and substance use frequency in a sample of 182 urban substance users. Specifically, the current study examined gender differences in the role of two potential explanatory variables, namely, difficulties controlling impulsive behavior when distressed (IMP), and a lack of emotional awareness and clarity (AW/CLAR). Multiple-group path modeling (across males and females) was used to examine gender differences in the path coefficients from PTSD symptoms to IMP and AW/CLAR, and from these latter variables to drug use frequency. Results indicated that PTSD symptoms were associated with IMP and AW/CLAR, and these path coefficients did not vary by gender. However, gender differences emerged when considering the path coefficients from AW/CLAR and IMP to substance use frequency. Specifically, for women, the association between PTSD and substance use was partially explained by IMP, whereas for men, the association between PTSD and substance use was partially explained by AW/CLAR. The current study is the first to examine gender differences in mechanisms accounting for the association between PTSD and substance use frequency, and these results also support the value and importance of examining gender differences in mechanisms underlying PTSD-SUD comorbidity. PMID:19423233

a Modified Genetic Algorithm for Finding Fuzzy Shortest Paths in Uncertain Networks

NASA Astrophysics Data System (ADS)

Heidari, A. A.; Delavar, M. R.

2016-06-01

In realistic network analysis, there are several uncertainties in the measurements and computation of the arcs and vertices. These uncertainties should also be considered in realizing the shortest path problem (SPP) due to the inherent fuzziness in the body of expert's knowledge. In this paper, we investigated the SPP under uncertainty to evaluate our modified genetic strategy. We improved the performance of genetic algorithm (GA) to investigate a class of shortest path problems on networks with vague arc weights. The solutions of the uncertain SPP with considering fuzzy path lengths are examined and compared in detail. As a robust metaheuristic, GA algorithm is modified and evaluated to tackle the fuzzy SPP (FSPP) with uncertain arcs. For this purpose, first, a dynamic operation is implemented to enrich the exploration/exploitation patterns of the conventional procedure and mitigate the premature convergence of GA technique. Then, the modified GA (MGA) strategy is used to resolve the FSPP. The attained results of the proposed strategy are compared to those of GA with regard to the cost, quality of paths and CPU times. Numerical instances are provided to demonstrate the success of the proposed MGA-FSPP strategy in comparison with GA. The simulations affirm that not only the proposed technique can outperform GA, but also the qualities of the paths are effectively improved. The results clarify that the competence of the proposed GA is preferred in view of quality quantities. The results also demonstrate that the proposed method can efficiently be utilized to handle FSPP in uncertain networks.

Objectively-measured outdoor time and physical and psychological function among older adults.

PubMed

Harada, Kazuhiro; Lee, Sangyoon; Lee, Sungchul; Bae, Seongryu; Harada, Kenji; Suzuki, Takao; Shimada, Hiroyuki

2017-10-01

Objective measurements of outdoor time are essential to establishing evidence about the health benefits of going outdoors among older adults. To better understanding the health benefits of going outdoors, clarification of potential mediators to connect going outdoors with health benefits is necessary. The present study aimed to investigate associations of objectively-measured outdoor time with older adults' physical and psychological function, and examine the mediating role of physical activity on these associations. Baseline data from a randomized control trial of physical activity among older adults with global cognitive impairment was used. Data from 192 participants were analyzed. Measures included steps-per-day, objectively-measured outdoor time per day using global positioning systems, physical function (cardiorespiratory fitness, lower-extremity strength), psychological function (depression, well-being) and basic factors. Path analysis showed that outdoor time was significantly associated with steps-per-day (path coefficient = 0.23) and depression (path coefficient = -0.16). Outdoor time was not directly associated with cardiorespiratory fitness, lower-extremity strength and well-being. However, steps-per-day was associated with cardiorespiratory fitness (path coefficient = 0.18), lower-extremity strength (path coefficient = -0.22) and well-being (path coefficient = 0.14). We found that objectively-measured outdoor time was indirectly associated with physical function, and both directly and indirectly with psychological function through physical activity among older adults. This finding indicates that going outdoors influences older adults' health outcomes, and is mainly mediated by physical activity. Geriatr Gerontol Int 2017; 17: 1455-1462. © 2016 Japan Geriatrics Society.

Understanding Associations between Neighborhood Socioeconomic Status and Negative Consequences of Drinking: A Moderated Mediation Analysis

PubMed Central

Karriker-Jaffe, Katherine J.; Liu, HuiGuo; Kaplan, Lauren M.

2016-01-01

Aims We explored how neighborhood socioeconomic status (SES) is related to negative consequences of drinking to explain why racial/ethnic minority group members are more at risk than Whites for adverse alcohol outcomes. We tested direct and indirect effects of neighborhood SES on alcohol problems and examined differences by gender and race. Methods We used data from the 2000 and 2005 National Alcohol Surveys (N=7,912 drinkers aged 18 and older; 49% female) linked with data from the 2000 Decennial Census in multivariate path models adjusting for individual demographics. Results In the full sample, neighborhood disadvantage had a significant direct path to increased negative consequences, with no indirect paths through depression, positive affect or pro-drinking attitudes. Neighborhood affluence had significant indirect paths to increased negative consequences through greater pro-drinking attitudes and increased heavy drinking. Sub-group analyses showed the indirect path from affluence to consequences held for White men, with no effects of neighborhood disadvantage. For racial/ethnic minority men, significant indirect paths emerged from both neighborhood disadvantage and affluence to increased consequences through greater pro-drinking attitudes and more heavy drinking. For minority women, there was an indirect effect of neighborhood affluence through reduced depression to fewer drinking consequences. There were limited neighborhood effects on alcohol outcomes for White women. Conclusions Interventions targeting pro-drinking attitudes in both affluent and disadvantaged areas may help reduce alcohol-related problems among men. Initiatives to improve neighborhood conditions could enhance mental health of minority women and reduce alcohol-related health disparities. PMID:26898509

An examination of the degrees of freedom of human jaw motion in speech and mastication.

PubMed

Ostry, D J; Vatikiotis-Bateson, E; Gribble, P L

1997-12-01

The kinematics of human jaw movements were assessed in terms of the three orientation angles and three positions that characterize the motion of the jaw as a rigid body. The analysis focused on the identification of the jaw's independent movement dimensions, and was based on an examination of jaw motion paths that were plotted in various combinations of linear and angular coordinate frames. Overall, both behaviors were characterized by independent motion in four degrees of freedom. In general, when jaw movements were plotted to show orientation in the sagittal plane as a function of horizontal position, relatively straight paths were observed. In speech, the slopes and intercepts of these paths varied depending on the phonetic material. The vertical position of the jaw was observed to shift up or down so as to displace the overall form of the sagittal plane motion path of the jaw. Yaw movements were small but independent of pitch, and vertical and horizontal position. In mastication, the slope and intercept of the relationship between pitch and horizontal position were affected by the type of food and its size. However, the range of variation was less than that observed in speech. When vertical jaw position was plotted as a function of horizontal position, the basic form of the path of the jaw was maintained but could be shifted vertically. In general, larger bolus diameters were associated with lower jaw positions throughout the movement. The timing of pitch and yaw motion differed. The most common pattern involved changes in pitch angle during jaw opening followed by a phase predominated by lateral motion (yaw). Thus, in both behaviors there was evidence of independent motion in pitch, yaw, horizontal position, and vertical position. This is consistent with the idea that motions in these degrees of freedom are independently controlled.

Quantization of Simple Parametrized Systems

NASA Astrophysics Data System (ADS)

Ruffini, Giulio

1995-01-01

I study the canonical formulation and quantization of some simple parametrized systems using Dirac's formalism and the Becchi-Rouet-Stora-Tyutin (BRST) extended phase space method. These systems include the parametrized particle and minisuperspace. Using Dirac's formalism I first analyze for each case the construction of the classical reduced phase space. There are two separate features of these systems that may make this construction difficult: (a) Because of the boundary conditions used, the actions are not gauge invariant at the boundaries. (b) The constraints may have a disconnected solution space. The relativistic particle and minisuperspace have such complicated constraints, while the non-relativistic particle displays only the first feature. I first show that a change of gauge fixing is equivalent to a canonical transformation in the reduced phase space, thus resolving the problems associated with the first feature above. Then I consider the quantization of these systems using several approaches: Dirac's method, Dirac-Fock quantization, and the BRST formalism. In the cases of the relativistic particle and minisuperspace I consider first the quantization of one branch of the constraint at the time and then discuss the backgrounds in which it is possible to quantize simultaneously both branches. I motivate and define the inner product, and obtain, for example, the Klein-Gordon inner product for the relativistic case. Then I show how to construct phase space path integral representations for amplitudes in these approaches--the Batalin-Fradkin-Vilkovisky (BFV) and the Faddeev path integrals --from which one can then derive the path integrals in coordinate space--the Faddeev-Popov path integral and the geometric path integral. In particular I establish the connection between the Hilbert space representation and the range of the lapse in the path integrals. I also examine the class of paths that contribute in the path integrals and how they affect space-time covariance, concluding that it is consistent to take paths that move forward in time only when there is no electric field. The key elements in this analysis are the space-like paths and the behavior of the action under the non-trivial ( Z_2) element of the reparametrization group.

Two arm robot path planning in a static environment using polytopes and string stretching. Thesis

NASA Technical Reports Server (NTRS)

Schima, Francis J., III

1990-01-01

The two arm robot path planning problem has been analyzed and reduced into components to be simplified. This thesis examines one component in which two Puma-560 robot arms are simultaneously holding a single object. The problem is to find a path between two points around obstacles which is relatively fast and minimizes the distance. The thesis involves creating a structure on which to form an advanced path planning algorithm which could ideally find the optimum path. An actual path planning method is implemented which is simple though effective in most common situations. Given the limits of computer technology, a 'good' path is currently found. Objects in the workspace are modeled with polytopes. These are used because they can be used for rapid collision detection and still provide a representation which is adequate for path planning.

Identification of biomechanical nonlinearity in whole-body vibration using a reverse path multi-input-single-output method

NASA Astrophysics Data System (ADS)

Huang, Ya; Ferguson, Neil S.

2018-04-01

The study implements a classic signal analysis technique, typically applied to structural dynamics, to examine the nonlinear characteristics seen in the apparent mass of a recumbent person during whole-body horizontal random vibration. The nonlinearity in the present context refers to the amount of 'output' that is not correlated or coherent to the 'input', usually indicated by values of the coherence function that are less than unity. The analysis is based on the longitudinal horizontal inline and vertical cross-axis apparent mass of twelve human subjects exposed to 0.25-20 Hz random acceleration vibration at 0.125 and 1.0 ms-2 r.m.s. The conditioned reverse path frequency response functions (FRF) reveal that the uncorrelated 'linear' relationship between physical input (acceleration) and outputs (inline and cross-axis forces) has much greater variation around the primary resonance frequency between 0.5 and 5 Hz. By reversing the input and outputs of the physical system, it is possible to assemble additional mathematical inputs from the physical output forces and mathematical constructs (e.g. square root of inline force). Depending on the specific construct, this can improve the summed multiple coherence at frequencies where the response magnitude is low. In the present case this is between 6 and 20 Hz. The statistical measures of the response force time histories of each of the twelve subjects indicate that there are potential anatomical 'end-stops' for the sprung mass in the inline axis. No previous study has applied this reverse path multi-input-single-output approach to human vibration kinematic and kinetic data before. The implementation demonstrated in the present study will allow new and existing data to be examined using this different analytical tool.

Manual flying of curved precision approaches to landing with electromechanical instrumentation. A piloted simulation study

NASA Technical Reports Server (NTRS)

Knox, Charles E.

1993-01-01

A piloted simulation study was conducted to examine the requirements for using electromechanical flight instrumentation to provide situation information and flight guidance for manually controlled flight along curved precision approach paths to a landing. Six pilots were used as test subjects. The data from these tests indicated that flight director guidance is required for the manually controlled flight of a jet transport airplane on curved approach paths. Acceptable path tracking performance was attained with each of the three situation information algorithms tested. Approach paths with both multiple sequential turns and short final path segments were evaluated. Pilot comments indicated that all the approach paths tested could be used in normal airline operations.

Temporal variation of meandering intensity and domain-wide lateral oscillations of the Gulf Stream

NASA Technical Reports Server (NTRS)

Lee, Tong; Cornillon, Peter

1995-01-01

The path of the Gulf Stream exhibits two modes of variability: wavelike spatial meanders associated with instability processes and large-sale lateral shifts of the path presumably due to atmospheric forcing. The objectives of this study are to examine the temporal variation of the intensity of spatial meandering in the stream, to characterize large-scale lateral oscillations in the stream's path, and to study the correlation betwen these two dynamically distinct modes of variability. The data used for this analysis are path displacemets ofthe Gulf Stream between 75 deg and 60 deg W obtained from AVHRR-derived (Advanced Very High Resolution Radiometer) infrared images for the period April 1982 through December 1989. Meandering intensity, measured by the spatial root-mean-sqaure displacement of the stream path, displays a 9-month dominant periodicity which is persistent through the study period. The 9-month fluctuation in meandering intensity may be related to the interaction of Rosseby waves with the stream. Interannual variation of meandering intensity is also found to be significant, with meandering being mich more intense during 1985 than it was in 1987. Annual variation, however,is weak and not well-defined.The spatially averaged position of the stream, which reflects nonmeandering large-scale lateral oscillations of the stream path, is dominated by an annual cycle. On average, the mean position is farthest north in November and farthest south in April. The first empirical orthogonal function mode of the space-time path displacements represents lateral oscillatins that are in-phase over the space-time domain. Interannual oscillations are also observed and are found to be weaker than the annual oscillation. The eigenvalue of the first mode indicates that about 21.5% of the total space-time variability of the stream path can be attibuted to domain-wide lateral oscillation. The correlation between meandering intensity and domain-wide lateral oscillations is very weak.

Controlling female cancer in Argentina. Divergent initiatives and the road to fragmentation

PubMed Central

Eraso, Yolanda

2014-01-01

This article analyses the organisation of cancer control in Argentina, with a special focus on the initiatives, institutions, and models that targeted female or gynaecological cancers. It identifies and examines the main factors in the process of elaborating a national policy to control the disease drawing on a series of actors and instruments such as the state, medical professionals, institutions and services, and the use of technology (notably diagnostic tools) for the detection of the disease. It traces the developments in the organisation highlighting its transformations from a centralising to a decentralised model of service provision. Using the concept of «path-dependence» the article examines the continuities and changes observed in the organisation of female cancer critically signalling the particular time at which a path was taken where «fragmentation» became consolidated within the health system. It also argues that it was within the field of cancer diagnosis that Argentinian doctors first sought to create the foundational structures of cancer organisation. The article contends that the path-dependence analytical approach helps us acknowledge the importance of historical analysis in the identification of factors that led to the lack of service coordination, including the persistent strain between national/provincial states that hampered the development of comprehensive programmes, aspects that have continued to mark efforts in the elaboration of cancer policies to the present day. PMID:24944432

Controlling female cancer in Argentina. Divergent initiatives and the road to fragmentation.

PubMed

Eraso, Yolanda

2014-01-01

This article analyses the organisation of cancer control in Argentina, with a special focus on the initiatives, institutions, and models that targeted female or gynaecological cancers. It identifies and examines the main factors in the process of elaborating a national policy to control the disease drawing on a series of actors and instruments such as the state, medical professionals, institutions and services, and the use of technology (notably diagnostic tools) for the detection of the disease. It traces the developments in the organisation highlighting its transformations from a centralising to a decentralised model of service provision. Using the concept of "path-dependence" the article examines the continuities and changes observed in the organisation of female cancer critically signalling the particular time at which a path was taken where "fragmentation" became consolidated within the health system. It also argues that it was within the field of cancer diagnosis that Argentinian doctors first sought to create the foundational structures of cancer organisation. The article contends that the path-dependence analytical approach helps us acknowledge the importance of historical analysis in the identification of factors that led to the lack of service coordination, including the persistent strain between national/provincial states that hampered the development of comprehensive programmes, aspects that have continued to mark efforts in the elaboration of cancer policies to the present day.

Statistical Analysis of the First Passage Path Ensemble of Jump Processes

NASA Astrophysics Data System (ADS)

von Kleist, Max; Schütte, Christof; Zhang, Wei

2018-02-01

The transition mechanism of jump processes between two different subsets in state space reveals important dynamical information of the processes and therefore has attracted considerable attention in the past years. In this paper, we study the first passage path ensemble of both discrete-time and continuous-time jump processes on a finite state space. The main approach is to divide each first passage path into nonreactive and reactive segments and to study them separately. The analysis can be applied to jump processes which are non-ergodic, as well as continuous-time jump processes where the waiting time distributions are non-exponential. In the particular case that the jump processes are both Markovian and ergodic, our analysis elucidates the relations between the study of the first passage paths and the study of the transition paths in transition path theory. We provide algorithms to numerically compute statistics of the first passage path ensemble. The computational complexity of these algorithms scales with the complexity of solving a linear system, for which efficient methods are available. Several examples demonstrate the wide applicability of the derived results across research areas.

Dynamical mechanism in aero-engine gas path system using minimum spanning tree and detrended cross-correlation analysis

NASA Astrophysics Data System (ADS)

Dong, Keqiang; Zhang, Hong; Gao, You

2017-01-01

Identifying the mutual interaction in aero-engine gas path system is a crucial problem that facilitates the understanding of emerging structures in complex system. By employing the multiscale multifractal detrended cross-correlation analysis method to aero-engine gas path system, the cross-correlation characteristics between gas path system parameters are established. Further, we apply multiscale multifractal detrended cross-correlation distance matrix and minimum spanning tree to investigate the mutual interactions of gas path variables. The results can infer that the low-spool rotor speed (N1) and engine pressure ratio (EPR) are main gas path parameters. The application of proposed method contributes to promote our understanding of the internal mechanisms and structures of aero-engine dynamics.

Understanding the Black College Student Experience: The Relationships between Racial Identity, Social Support, General Campus, Academic, and Racial Climate, and GPA

ERIC Educational Resources Information Center

Hamilton, Tonisha

2010-01-01

According to the US Department of Education (2001), Black college students, when compared with other racial groups, have the highest drop out rate at both two-year and four-year colleges. The purpose of this study, therefore, was to examine factors that might place Black students at risk of discontinuing their higher education. A path analysis was…

Examination of Narcissistic Personality Traits' Predicting Level of Internet Addiction and Cyber Bullying through Path Analysis

ERIC Educational Resources Information Center

Eksi, Fusun

2012-01-01

The main aim of this study is to find out to what extent do narcissistic personality traits predict internet addiction and cyber bullying in vocational high school students. For this study five hundred and eight vocational high school students (331 male students--66,2%, 169 female students 33,8% and 8 unstated [x-bar] 16,24) from Anatolian side of…

The Different Paths in the Franchising Entrepreneurship Choice

NASA Astrophysics Data System (ADS)

Tomaras, Petros; Konstantopoulos, Nikolaos; Zondiros, Dimitris

2007-12-01

This study aims to testify the scientific veracity of the question: is the franchisees' choice on entrepreneurial start-up univocal or many-valued? Two variables are examined by registering daily activities of the entrepreneurial franchisees, as they appear by the answers given to a closed-ended questionnaire. We proceeded with a multiple variable statistical analysis (principal component analysis) of survey data collected from franchisees of a Greece-based franchise system. The results of the research indicate that among different value standards, the entrepreneurs conclude in choosing the franchising.

The impact of early shame memories in Binge Eating Disorder: The mediator effect of current body image shame and cognitive fusion.

PubMed

Duarte, Cristiana; Pinto-Gouveia, José

2017-12-01

This study examined the phenomenology of shame experiences from childhood and adolescence in a sample of women with Binge Eating Disorder. Moreover, a path analysis was investigated testing whether the association between shame-related memories which are traumatic and central to identity, and binge eating symptoms' severity, is mediated by current external shame, body image shame and body image cognitive fusion. Participants in this study were 114 patients, who were assessed through the Eating Disorder Examination and the Shame Experiences Interview, and through self-report measures of external shame, body image shame, body image cognitive fusion and binge eating symptoms. Shame experiences where physical appearance was negatively commented or criticized by others were the most frequently recalled. A path analysis showed a good fit between the hypothesised mediational model and the data. The traumatic and centrality qualities of shame-related memories predicted current external shame, especially body image shame. Current shame feelings were associated with body image cognitive fusion, which, in turn, predicted levels of binge eating symptomatology. Findings support the relevance of addressing early shame-related memories and negative affective and self-evaluative experiences, namely related to body image, in the understanding and management of binge eating. Copyright © 2017 Elsevier B.V. All rights reserved.

Cognitive Factors of Using Health Apps: Systematic Analysis of Relationships Among Health Consciousness, Health Information Orientation, eHealth Literacy, and Health App Use Efficacy

PubMed Central

Cho, Jaehee

2014-01-01

Background Interest in smartphone health apps has been increasing recently. However, we have little understanding of the cognitive and motivational factors that influence the extent of health-app use. Objective This study aimed to examine the effects of four cognitive factors—health consciousness, health information orientation, eHealth literacy, and health-app use efficacy—on the extent of health-app use. It also explored the influence of two different use patterns—information and information-behavior use of health apps—with regard to the relationships among the main study variables. Methods We collected and analyzed 765 surveys in South Korea. According to the results, there was a negligible gender difference: males (50.6%, 387/765) and females (49.4%, 378/765). All participants were adults whose ages ranged from 19 to 59. In order to test the proposed hypotheses, we used a path analysis as a specific form of structural equation modeling. Results Through a path analysis, we discovered that individuals’ health consciousness had a direct effect on their use of health apps. However, unlike the initial expectations, the effects of health information orientation and eHealth literacy on health-app use were mediated by health-app use efficacy. Conclusions The results from the path analysis addressed a significant direct effect of health consciousness as well as strong mediating effects of health-app use efficacy. These findings contribute to widening our comprehension of the new, digital dimensions of health management, particularly those revolving around mobile technology. PMID:24824062

Fetal exposure to propoxur and abnormal child neurodevelopment at 2 years of age

PubMed Central

Ostrea, Enrique M.; Reyes, Alexis; Villanueva-Uy, Esterlita; Pacifico, Rochelle; Benitez, Bernadette; Ramos, Essie; Bernardo, Rommel C.; Bielawski, Dawn M.; Delaney-Black, Virginia; Chiodo, Lisa; Janisse, James J.; Ager, Joel W.

2012-01-01

Objective Our aim was to determine the effects of fetal exposure to propoxur and pyrethroids, on child neurodevelopment at 2 years of age. Patients and Methods Mothers were prospectively recruited during mid-pregnancy in Bulacan, Philippines where multiple pesticides including propoxur, cyfluthrin, chlorpyrifos, cypermethrin, pretilachlor, bioallethrin, malathion, diazinon and transfluthrin are used. To detect prenatal exposure to these pesticides, maternal hair and blood, infant’s hair, cord blood, and meconium were analyzed for the pesticides by gas chromatography/mass spectrometry. Infants were examined at 2 years of age with 95.1% follow up rate and their neurodevelopment outcome was assessed by the Griffiths Mental Developmental Scale (N=754). Results Meconium analysis was the most sensitive method to detect fetal exposure to pesticides and exposure was highest for propoxur (21.3%) and the grouped pyrethroids (2.5% - bioallethrin, transfluthrin, cyfluthrin and cypermethrin). Path analysis modeling was performed to determine the effects of fetal exposure to propoxur and pyrethroids on the child’s neurodevelopment at 24 months of age while controlling for confounders. Only singletons and those with complete data for the path analysis were included (N=696). Using a path analysis model, there was a significant negative (β= −0.14, p<0.001) relationship between prenatal pesticide exposure to propoxur and motor development at 2 years of age after controlling for confounders, e.g., infant gender, socioeconomic status, maternal intelligence, home stimulation (HOME), postnatal exposure to propoxur and blood lead level at 2 years of age. Conclusion At 2 years of age, prenatal exposure to propoxur was associated with poorer motor development in children. PMID:22155319

Influence of the medication environment on the unsafe medication behavior of nurses: A path analysis.

PubMed

Yu, Xi; Li, Ce; Gao, Xueqin; Liu, Furong; Lin, Ping

2018-04-20

To explore the relationship between the medication environment and the unsafe medication behavior of nurses and to analyze its influence path. Unsafe medication behavior is the direct cause of medication error. The organizational environment is the foundation of and plays a guiding role in work behavior. Whether the medication environment correlates with the unsafe medication behavior of nurses remains unclear. This study used a correlative design with self-administered questionnaires, and the SHEL model, an acronym of its elements of software, hardware, environment, and liveware, was used as the framework for the medication environment. A survey was conducted among 1012 clinical nurses from five tertiary hospitals in China using the nurse unsafe medication behavior scale (NUMBS) and the nurses' perceptions of the medication environment scale (NPMES). Data were collected from January to February 2017. Path analyses were used to examine the hypothesized model. The medication environment correlated negatively with unsafe medication behavior (r=-0.48, p<0.001). The path analysis showed that software, liveware and nurses' personal factors directly affected unsafe medication behavior. Software, hardware and the environment indirectly influenced unsafe medication behavior, and nurses' personal factors played a mediating role in the relationships of unsafe medication behavior with software, hardware, and the environment. The unsafe medication behavior of nurses should be further improved. The medication environment was a predictor of unsafe medication behavior. Care managers should actively improve the medication environment to reduce the incidence of unsafe medication behaviors. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

The Case for Including Adverse Childhood Experiences in Child Maltreatment Education: A Path Analysis

PubMed Central

Bachmann, Michael; Bachmann, Brittany A

2018-01-01

Context The lifelong, negative consequences of exposure to adverse childhood experiences (ACEs) for individuals and their families are well established. Objective To demonstrate the importance of including ACE information in child maltreatment education curricula using path analysis. Design Survey data examined the impact of child maltreatment education programs and knowledge about ACEs on medical practitioners’ reporting habits and ability to detect maltreatment. A path diagram distinguished between the direct impact of education programs on outcome measures and the indirect effect that is mediated through knowledge of ACEs. Main Outcome Measures Medical practitioners’ ability to detect child maltreatment and their number of referrals to Child Protective Services (CPS). Results The optimized path diagram (χ2SB(3) = 3.9, p = 0.27; RMSEA-SB = 0.017; R2 = 0.21, where SB is Satorra-Bentler coefficient and RMSEA is root-mean-square error of approximation) revealed the mediating variable “knowledge about ACEs” as the strongest structural effect (SB-β = 0.34) on the number of CPS referrals. It was almost twice as high as the second strongest effect of formal education programs (SB-β = 0.19). For workplace training programs, the total effect when including knowledge of ACEs was almost double as strong as the direct effect alone. Even when previous child maltreatment education was controlled for, practitioners familiar with the consequences of ACEs were significantly more likely to recognize and to report abuse to CPS. Conclusion This study documented the importance of specialized training programs on ACEs, and the essential role ACE knowledge plays in the effectiveness of provider education programs. PMID:29616910

The Case for Including Adverse Childhood Experiences in Child Maltreatment Education: A Path Analysis.

PubMed

Bachmann, Michael; Bachmann, Brittany A

2018-03-16

The lifelong, negative consequences of exposure to adverse childhood experiences (ACEs) for individuals and their families are well established. To demonstrate the importance of including ACE information in child maltreatment education curricula using path analysis. Survey data examined the impact of child maltreatment education programs and knowledge about ACEs on medical practitioners' reporting habits and ability to detect maltreatment. A path diagram distinguished between the direct impact of education programs on outcome measures and the indirect effect that is mediated through knowledge of ACEs. Medical practitioners' ability to detect child maltreatment and their number of referrals to Child Protective Services (CPS). The optimized path diagram (χ 2 SB(3) = 3.9, p = 0.27; RMSEA-SB = 0.017; R 2 = 0.21, where SB is Satorra-Bentler coefficient and RMSEA is root-mean-square error of approximation) revealed the mediating variable "knowledge about ACEs" as the strongest structural effect (SB-β = 0.34) on the number of CPS referrals. It was almost twice as high as the second strongest effect of formal education programs (SB-β = 0.19). For workplace training programs, the total effect when including knowledge of ACEs was almost double as strong as the direct effect alone. Even when previous child maltreatment education was controlled for, practitioners familiar with the consequences of ACEs were significantly more likely to recognize and to report abuse to CPS. This study documented the importance of specialized training programs on ACEs, and the essential role ACE knowledge plays in the effectiveness of provider education programs.

Class start times, sleep, and academic performance in college: a path analysis.

PubMed

Onyper, Serge V; Thacher, Pamela V; Gilbert, Jack W; Gradess, Samuel G

2012-04-01

Path analysis was used to examine the relationship between class start times, sleep, circadian preference, and academic performance in college-aged adults. Consistent with observations in middle and high school students, college students with later class start times slept longer, experienced less daytime sleepiness, and were less likely to miss class. Chronotype was an important moderator of sleep schedules and daytime functioning; those with morning preference went to bed and woke up earlier and functioned better throughout the day. The benefits of taking later classes did not extend to academic performance, however; grades were somewhat lower in students with predominantly late class schedules. Furthermore, students taking later classes were at greater risk for increased alcohol consumption, and among all the factors affecting academic performance, alcohol misuse exerted the strongest effect. Thus, these results indicate that later class start times in college, while allowing for more sleep, also increase the likelihood of alcohol misuse, ultimately impeding academic success.

The role of natural disaster in individual and relational adjustment in Sri Lankan mothers following the 2004 tsunami.

PubMed

Banford, Alyssa; Ivey, David C; Wickrama, Thulitha; Fischer, Judith; Prouty, Anne; Smith, Douglas

2016-01-01

The purpose of this study is to examine the associations between maternal mental health distress symptoms, including depression and post-traumatic stress disorder, the extent to which the presence of a child's disaster-related physical health problem(s) have interfered with daily functioning, and family cohesion over time among Sri Lankan mothers who survived the tsunami on 26 December 2004. Study variables were measured using a self-report questionnaire administered approximately four months after the event and three years later in summer 2008. Univariate, bivariate, and multivariate analyses were conducted. Path analysis was employed to assess the relationships between the key variables over time and the correlations in the study variables at each time point. Among other findings, the results of the path analysis indicated that post-traumatic stress symptom distress four months after the disaster significantly predicted variance in family cohesion three years later. Clinical and empirical research implications are presented and discussed. © 2016 The Author(s). Disasters © Overseas Development Institute, 2016.

A multilevel path analysis of contact frequency between social network members

NASA Astrophysics Data System (ADS)

van den Berg, Pauline; Arentze, Theo; Timmermans, Harry

2012-04-01

Recently, there has been an increasing interest in the role of social networks in spatial-choice and travel behavior. It has been acknowledged that social activities and the travel for these activities can emerge from individuals' social networks and that social activities are responsible for an important portion of travel demand. The influence of information and communication technologies (ICT's) is also important in this respect. The purpose of the paper is to examine the effects of characteristics of egos and ego-alter relationships on the frequency of social interaction by different communication modes, using multilevel path analysis. The analyses are based on social network data collected in 2008 in the Eindhoven region in the Netherlands among 116 respondents. The results indicate a complementary relationship between contact frequencies by different modes. The contact frequencies of the different modes, especially face-to-face and telephone, can also be largely explained by the ego's personal characteristics and the type of relationship and the distance between ego and alter.

Disclosure appraisal mediating the association between perceived stigma and HIV disclosure to casual sex partners among HIV+ MSM: a path model analysis.

PubMed

Li, Haochu; Chen, Xinguang; Yu, Bin

2016-01-01

HIV stigma is widely believed to be related to HIV disclosure. However, there is a dearth of studies examining the mechanisms that link stigma to disclosure. This is a specific study to assess the relationship between perceived stigma and HIV disclosure to casual sex partners based on a social cognitive theory. HIV+ men who have sex with men (MSM) from two US cities (N = 297) completed questionnaires administered using audio computer-assisted self-interviewing. Path modeling analysis was used to assess the theory-based structural relationships. Perceived stigma was negatively associated with attitudes, intention and behavior of HIV disclosure to casual sex partners. The association was fully mediated by disclosure appraisal, including disclosure outcome expectations, costs and self-efficacy. Findings of this study add new knowledge regarding HIV stigma and disclosure, and provide timely data supporting more effective behavioral interventions to encourage HIV disclosure among MSM.

Relationships among grit, academic performance, perceived academic failure, and stress in associate degree students.

PubMed

Lee, Wincy Wing Sze

2017-10-01

The present study examined the relationships among grit, academic performance, perceived academic failure, and stress levels of Hong Kong associate degree students using path analysis. Three hundred and forty-five students from a community college in Hong Kong voluntarily participated in the study. They completed a questionnaire that measured their grit (operationalized as interest and perseverance) and stress levels. The students also provided their actual academic performance and evaluated their perception of their academic performance as a success or a failure. The results of the path analysis showed that interest and perseverance were negatively associated with stress, and only perceived academic failure was positively associated with stress. These findings suggest that psychological appraisal and resources are more important antecedents of stress than objective negative events. Therefore, fostering students' psychological resilience may alleviate the stress experienced by associate degree students or college students in general. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

MapMaker and PathTracer for tracking carbon in genome-scale metabolic models

PubMed Central

Tervo, Christopher J.; Reed, Jennifer L.

2016-01-01

Constraint-based reconstruction and analysis (COBRA) modeling results can be difficult to interpret given the large numbers of reactions in genome-scale models. While paths in metabolic networks can be found, existing methods are not easily combined with constraint-based approaches. To address this limitation, two tools (MapMaker and PathTracer) were developed to find paths (including cycles) between metabolites, where each step transfers carbon from reactant to product. MapMaker predicts carbon transfer maps (CTMs) between metabolites using only information on molecular formulae and reaction stoichiometry, effectively determining which reactants and products share carbon atoms. MapMaker correctly assigned CTMs for over 97% of the 2,251 reactions in an Escherichia coli metabolic model (iJO1366). Using CTMs as inputs, PathTracer finds paths between two metabolites. PathTracer was applied to iJO1366 to investigate the importance of using CTMs and COBRA constraints when enumerating paths, to find active and high flux paths in flux balance analysis (FBA) solutions, to identify paths for putrescine utilization, and to elucidate a potential CO2 fixation pathway in E. coli. These results illustrate how MapMaker and PathTracer can be used in combination with constraint-based models to identify feasible, active, and high flux paths between metabolites. PMID:26771089

A Path to Discovery

ERIC Educational Resources Information Center

Stegemoller, William; Stegemoller, Rebecca

2004-01-01

The path taken and the turns made as a turtle traces a polygon are examined to discover an important theorem in geometry. A unique tool, the Angle Adder, is implemented in the investigation. (Contains 9 figures.)

Global Qualitative Flow-Path Modeling for Local State Determination in Simulation and Analysis

NASA Technical Reports Server (NTRS)

Malin, Jane T. (Inventor); Fleming, Land D. (Inventor)

1998-01-01

For qualitative modeling and analysis, a general qualitative abstraction of power transmission variables (flow and effort) for elements of flow paths includes information on resistance, net flow, permissible directions of flow, and qualitative potential is discussed. Each type of component model has flow-related variables and an associated internal flow map, connected into an overall flow network of the system. For storage devices, the implicit power transfer to the environment is represented by "virtual" circuits that include an environmental junction. A heterogeneous aggregation method simplifies the path structure. A method determines global flow-path changes during dynamic simulation and analysis, and identifies corresponding local flow state changes that are effects of global configuration changes. Flow-path determination is triggered by any change in a flow-related device variable in a simulation or analysis. Components (path elements) that may be affected are identified, and flow-related attributes favoring flow in the two possible directions are collected for each of them. Next, flow-related attributes are determined for each affected path element, based on possibly conflicting indications of flow direction. Spurious qualitative ambiguities are minimized by using relative magnitudes and permissible directions of flow, and by favoring flow sources over effort sources when comparing flow tendencies. The results are output to local flow states of affected components.

Differences in environmental preferences towards cycling for transport among adults: a latent class analysis.

PubMed

Mertens, Lieze; Van Cauwenberg, Jelle; Ghekiere, Ariane; De Bourdeaudhuij, Ilse; Deforche, Benedicte; Van de Weghe, Nico; Van Dyck, Delfien

2016-08-12

Increasing cycling for transport can contribute to improve public health among adults. Micro-environmental factors (i.e. small-scaled street-setting features) may play an important role in affecting the street's appeal to cycle for transport. Understanding about the interplay between individuals and their physical environment is important to establish tailored environmental interventions. Therefore, the current study aimed to examine whether specific subgroups exist based on similarities in micro-environmental preferences to cycle for transport. Responses of 1950 middle-aged adults (45-65 years) on a series of choice tasks depicting potential cycling routes with manipulated photographs yielded three subgroups with different micro-environmental preferences using latent class analysis. Although latent class analysis revealed three different subgroups in the middle-aged adult population based on their environmental preferences, results indicated that cycle path type (i.e. a good separated cycle path) is the most important environmental factor for all participants and certainly for individuals who did not cycle for transport. Furthermore, only negligible differences were found between the importances of the other micro-environmental factors (i.e. traffic density, evenness of the cycle path, maintenance, vegetation and speed limits) regarding the two at risk subgroups and that providing a speed bump obviously has the least impact on the street's appeal to cycle for transport. Results from the current study indicate that only negligible differences were found between the three subgroups. Therefore, it might be suggested that tailored environmental interventions are not required in this research context.

Multiple-path model of spectral reflectance of a dyed fabric.

PubMed

Rogers, Geoffrey; Dalloz, Nicolas; Fournel, Thierry; Hebert, Mathieu

2017-05-01

Experimental results are presented of the spectral reflectance of a dyed fabric as analyzed by a multiple-path model of reflection. The multiple-path model provides simple analytic expressions for reflection and transmission of turbid media by applying the Beer-Lambert law to each path through the medium and summing over all paths, each path weighted by its probability. The path-length probability is determined by a random-walk analysis. The experimental results presented here show excellent agreement with predictions made by the model.

A taxonomy of integral reaction path analysis

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

Grcar, Joseph F.; Day, Marcus S.; Bell, John B.

2004-12-23

W. C. Gardiner observed that achieving understanding through combustion modeling is limited by the ability to recognize the implications of what has been computed and to draw conclusions about the elementary steps underlying the reaction mechanism. This difficulty can be overcome in part by making better use of reaction path analysis in the context of multidimensional flame simulations. Following a survey of current practice, an integral reaction flux is formulated in terms of conserved scalars that can be calculated in a fully automated way. Conditional analyses are then introduced, and a taxonomy for bidirectional path analysis is explored. Many examplesmore » illustrate the resulting path analysis and uncover some new results about nonpremixed methane-air laminar jets.« less

Comparative Analysis of English Language Student's School Paths at a Mexico University

ERIC Educational Resources Information Center

Robelo, Octaviano García; Marquez, Jorge Hernández; Pérez, Ileana Casasola

2017-01-01

Seven factors related to academic paths of students of the Bachelor of English Language of a public university in Mexico are investigated. With a non-experimental descriptive design, a Likert scale was applied to evaluate the college students' perception of these factors. A comparative analysis between three types of school paths was performed. It…

Path Analysis and Residual Plotting as Methods of Environmental Scanning in Higher Education: An Illustration with Applications and Enrollments.

ERIC Educational Resources Information Center

Morcol, Goktug; McLaughlin, Gerald W.

1990-01-01

The study proposes using path analysis and residual plotting as methods supporting environmental scanning in strategic planning for higher education institutions. Path models of three levels of independent variables are developed. Dependent variables measuring applications and enrollments at Virginia Polytechnic Institute and State University are…

Selection of test paths for solder joint intermittent connection faults under DC stimulus

NASA Astrophysics Data System (ADS)

Huakang, Li; Kehong, Lv; Jing, Qiu; Guanjun, Liu; Bailiang, Chen

2018-06-01

The test path of solder joint intermittent connection faults under direct-current stimulus is examined in this paper. According to the physical structure of the circuit, a network model is established first. A network node is utilised to represent the test node. The path edge refers to the number of intermittent connection faults in the path. Then, the selection criteria of the test path based on the node degree index are proposed and the solder joint intermittent connection faults are covered using fewer test paths. Finally, three circuits are selected to verify the method. To test if the intermittent fault is covered by the test paths, the intermittent fault is simulated by a switch. The results show that the proposed method can detect the solder joint intermittent connection fault using fewer test paths. Additionally, the number of detection steps is greatly reduced without compromising fault coverage.

Positive and negative social exchanges and cognitive aging in young-old adults: differential associations across family, friend, and spouse domains.

PubMed

Windsor, Tim D; Gerstorf, Denis; Pearson, Elissa; Ryan, Lindsay H; Anstey, Kaarin J

2014-03-01

We examined how positive and negative social exchanges with friends, family, and spouses were related to cognitive aging in episodic and working memory, and perceptual speed. To do so, we used a large sample of cognitively intact young-old participants from the PATH Through Life Study (PATH; aged 60 to 64 years at baseline, n = 1,618) who were assessed on 3 occasions over 8 years. Additional replication analyses were conducted using the Health and Retirement Study (HRS), which provided data on episodic memory. The main analysis of PATH Through Life showed that positive exchanges with friends and family were associated with less decline in perceptual speed, with these associations attenuated by adjustment for physical functioning and depressive symptoms. Negative exchanges with spouses were associated with poorer working memory performance. Positive exchanges with friends were associated with better initial episodic memory in both PATH and HRS. More frequent negative exchanges with friends and family were associated with better episodic memory in the PATH sample. However, these findings were not replicated in HRS. Our findings provide indirect support for the role of social exchange quality in contributing to cognitive enrichment. However, the inconsistent pattern of results across cognitive and social exchange domains points to possibilities of reverse causality, and may also indicate that social exchange quality plays a less important role for cognitive enrichment than other psychosocial characteristics. (c) 2014 APA, all rights reserved.

Effects of human and organizational deficiencies on workers'safety behavior in a mining site in Iran.

PubMed

Mirzaei Aliabadi, Mostafa; Aghaei, Hamed; Kalatpour, Omid; Soltanian, Ali Reza; SeyedTabib, Maryam

2018-05-18

Mines are a dangerous workplace worldwide with a high accident rate. According to the Statistical Center of Iran, the number of occupational accidents in Iranian mines has increased in recent years. This study determined and explained human and organizational deficiencies influencing Iranian mining accidents. In this study, the data associated with 305 mining accidents were investigated. The data were analyzed based on a systems analysis approach to identify critical deficiencies in organizational influences, unsafe supervision, preconditions for unsafe acts, and workers' unsafe acts. Partial Least Square Structural Equation Modeling [PLS-SEM] was utilized for modeling the interactions between these deficiencies. It was demonstrated that organizational deficiencies had a direct positive effect on workers' violations (path coefficient=0.16) and workers' errors (path coefficient=0.23). The effect of unsafe supervision on workers' violations and workers' errors was also significant with the path coefficients of 0.14 and 0.20. Likewise, preconditions for unsafe acts also had a significant effect on both workers' violations (path coefficient=0.16) and workers' errors (path coefficient=0.21). Moreover, organizational deficiencies had an indirect positive effect on workers' unsafe acts mediated by unsafe supervision and preconditions for unsafe acts. Among the variables examined in the current study, organizational influences had the strongest impacts on workers' unsafe acts. Organizational deficiencies are the main causes of accidents in mining sectors that affects all other aspects of system safety. For preventing occupational accidents, organizational deficiencies should be modified first.

The efficiency of parameter estimation of latent path analysis using summated rating scale (SRS) and method of successive interval (MSI) for transformation of score to scale

NASA Astrophysics Data System (ADS)

Solimun, Fernandes, Adji Achmad Rinaldo; Arisoesilaningsih, Endang

2017-12-01

Research in various fields generally investigates systems and involves latent variables. One method to analyze the model representing the system is path analysis. The data of latent variables measured using questionnaires by applying attitude scale model yields data in the form of score, before analyzed should be transformation so that it becomes data of scale. Path coefficient, is parameter estimator, calculated from scale data using method of successive interval (MSI) and summated rating scale (SRS). In this research will be identifying which data transformation method is better. Path coefficients have smaller varieties are said to be more efficient. The transformation method that produces scaled data and used in path analysis capable of producing path coefficients (parameter estimators) with smaller varieties is said to be better. The result of analysis using real data shows that on the influence of Attitude variable to Intention Entrepreneurship, has relative efficiency (ER) = 1, where it shows that the result of analysis using data transformation of MSI and SRS as efficient. On the other hand, for simulation data, at high correlation between items (0.7-0.9), MSI method is more efficient 1.3 times better than SRS method.

minepath.org: a free interactive pathway analysis web server.

PubMed

Koumakis, Lefteris; Roussos, Panos; Potamias, George

2017-07-03

( www.minepath.org ) is a web-based platform that elaborates on, and radically extends the identification of differentially expressed sub-paths in molecular pathways. Besides the network topology, the underlying MinePath algorithmic processes exploit exact gene-gene molecular relationships (e.g. activation, inhibition) and are able to identify differentially expressed pathway parts. Each pathway is decomposed into all its constituent sub-paths, which in turn are matched with corresponding gene expression profiles. The highly ranked, and phenotype inclined sub-paths are kept. Apart from the pathway analysis algorithm, the fundamental innovation of the MinePath web-server concerns its advanced visualization and interactive capabilities. To our knowledge, this is the first pathway analysis server that introduces and offers visualization of the underlying and active pathway regulatory mechanisms instead of genes. Other features include live interaction, immediate visualization of functional sub-paths per phenotype and dynamic linked annotations for the engaged genes and molecular relations. The user can download not only the results but also the corresponding web viewer framework of the performed analysis. This feature provides the flexibility to immediately publish results without publishing source/expression data, and get all the functionality of a web based pathway analysis viewer. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

Performance analysis of a GPS Interferometric attitude determination system for a gravity gradient stabilized spacecraft. M.S. Thesis

NASA Technical Reports Server (NTRS)

Stoll, John C.

1995-01-01

The performance of an unaided attitude determination system based on GPS interferometry is examined using linear covariance analysis. The modelled system includes four GPS antennae onboard a gravity gradient stabilized spacecraft, specifically the Air Force's RADCAL satellite. The principal error sources are identified and modelled. The optimal system's sensitivities to these error sources are examined through an error budget and by varying system parameters. The effects of two satellite selection algorithms, Geometric and Attitude Dilution of Precision (GDOP and ADOP, respectively) are examined. The attitude performance of two optimal-suboptimal filters is also presented. Based on this analysis, the limiting factors in attitude accuracy are the knowledge of the relative antenna locations, the electrical path lengths from the antennae to the receiver, and the multipath environment. The performance of the system is found to be fairly insensitive to torque errors, orbital inclination, and the two satellite geometry figures-of-merit tested.

Analysis and elimination of a bias in targeted molecular dynamics simulations of conformational transitions: application to calmodulin.

PubMed

Ovchinnikov, Victor; Karplus, Martin

2012-07-26

The popular targeted molecular dynamics (TMD) method for generating transition paths in complex biomolecular systems is revisited. In a typical TMD transition path, the large-scale changes occur early and the small-scale changes tend to occur later. As a result, the order of events in the computed paths depends on the direction in which the simulations are performed. To identify the origin of this bias, and to propose a method in which the bias is absent, variants of TMD in the restraint formulation are introduced and applied to the complex open ↔ closed transition in the protein calmodulin. Due to the global best-fit rotation that is typically part of the TMD method, the simulated system is guided implicitly along the lowest-frequency normal modes, until the large spatial scales associated with these modes are near the target conformation. The remaining portion of the transition is described progressively by higher-frequency modes, which correspond to smaller-scale rearrangements. A straightforward modification of TMD that avoids the global best-fit rotation is the locally restrained TMD (LRTMD) method, in which the biasing potential is constructed from a number of TMD potentials, each acting on a small connected portion of the protein sequence. With a uniform distribution of these elements, transition paths that lack the length-scale bias are obtained. Trajectories generated by steered MD in dihedral angle space (DSMD), a method that avoids best-fit rotations altogether, also lack the length-scale bias. To examine the importance of the paths generated by TMD, LRTMD, and DSMD in the actual transition, we use the finite-temperature string method to compute the free energy profile associated with a transition tube around a path generated by each algorithm. The free energy barriers associated with the paths are comparable, suggesting that transitions can occur along each route with similar probabilities. This result indicates that a broad ensemble of paths needs to be calculated to obtain a full description of conformational changes in biomolecules. The breadth of the contributing ensemble suggests that energetic barriers for conformational transitions in proteins are offset by entropic contributions that arise from a large number of possible paths.

Impact of cognitive task on the posture of elderly subjects with Alzheimer's disease compared to healthy elderly subjects.

PubMed

Manckoundia, Patrick; Pfitzenmeyer, Pierre; d'Athis, Philippe; Dubost, Véronique; Mourey, France

2006-02-01

The aims of this study were to analyze the effects of cognitive task on static posture in Alzheimer's disease (AD) and in healthy elderly (HE) subjects and to evaluate whether those effects were greater in AD subjects than in HE subjects. We performed a posturographic analysis on 13 subjects with mild AD (mean age, 79.7+/-5.1 years, Mini-Mental State Examination scores between 18 and 23) and on 17 HE subjects (mean age, 78.5+/-4.4 years). After watching a video sequence, the subjects were asked to maintain a stable upright posture while standing on a force platform. Then, the postural sway was measured during the following two conditions: (1) quiet standing and (2) both standing and answering questions about the video sequence. We were interested in the center of pressure (CoP) area and path. For each group, the single task was compared to the dual task for the CoP area and path. We also compared the variability of both CoP area (variation of the CoP area between the single and the dual task) and path (variation of the CoP path between the single and the dual task) between the two groups. We showed that there was no significant difference between the single and the dual task in HE subjects concerning the CoP area and path, in contrast to the AD group, and that variability of both the CoP area and path were significantly greater in the AD subjects than in the HE subjects. This finding may contribute to the risk of falls in AD patients. Copyright (c) 2005 Movement Disorder Society.

Structural Equation Modeling of the Effects of Family, Preschool, and Stunting on the Cognitive Development of School Children

PubMed Central

Ajayi, Oluwakemi Rachel; Matthews, Glenda Beverley; Taylor, Myra; Kvalsvig, Jane Dene; Davidson, Leslie; Kauchali, Shuaib; Mellins, Claude

2017-01-01

A recent study based on a sample of 1,580 children from five adjacent geographical locations in KwaZulu-Natal, South Africa, was carried out to examine the association of nutrition, family influence, preschool education, and disadvantages in geographical location with the cognitive development of school children. Data were collected on the children from 2009 to 2011 for this developmental study and included cognitive scores and information on the health and nutrition of the children. The current study analyzed the association of demographic variables (geographical location (site)), child variables (sex, preschool education and socioeconomic status), parental level of education (maternal and paternal), child’s health (HIV status and hemoglobin level) and anthropometric measures of nutritional status (height-for-age) with children’s cognitive outcomes. The hypothesis is that the nutritional status of children is a pathway through which the indirect effects of the variables of interest exert influence on their cognitive outcomes. Factor analysis based on principal components was used to create a variable based on the cognitive measures, correlations were used to examine the bivariate association between the variables of interest in the preliminary analysis and a path analysis was constructed, which was used for the disaggregation of the direct and indirect effects of the predictors for each cognitive test in a structural equation model. The results revealed that nutritional status directly predicts cognitive test scores and is a path through which other variables indirectly influence children’s cognitive outcome and development. PMID:28555186

Sociocultural adjustment among sojourning Malaysian students in Britain: a replication and path analytic extension.

PubMed

Swami, Viren; Arteche, Adriane; Chamorro-Premuzic, Tomas; Furnham, Adrian

2010-01-01

The present study examined the sociocultural adjustment of 249 sojourning Malaysian undergraduates in Britain. One-hundred and ten Malay and 139 Chinese students enrolled in various courses answered a self-report questionnaire that examined various aspects of sociocultural adjustment and socio-demographics. Overall, Malay students reported significantly poorer sociocultural adjustment than Chinese students, as well as more negative outcomes on a range of predictors. Path analysis for the total sample showed that higher family income led to greater sociocultural adjustment, but partially because it led to more contact with host and conationals, better language proficiency, lower perceived cultural differences and less perceived discrimination. Moreover, participants with higher English proficiency were better adapted, but partially because they perceived less cultural differences as well as having more contact with host nationals. Additionally, individuals reporting better sociocultural adjustment also reported better health statuses. The same model was equally useful at predicting sociocultural adjustment for both Malay and Chinese participants. These results are discussed in terms of the role played by income in buffering against the negative aspects of sociocultural adjustment.

Self-regulation as a mediator between sibling relationship quality and early adolescents' positive and negative outcomes.

PubMed

Padilla-Walker, Laura M; Harper, James M; Jensen, Alexander C

2010-08-01

The current study examined the role of adolescents' self-regulation as a mediator between sibling relationship quality and adolescent outcomes, after controlling for the quality of the parent-child relationship. Participants were 395 families (282 two parent; 113 single parent) with an adolescent child (M age of child at Time 1 = 11.15, SD = .96, 49% female) who took part in [project name masked for blind review] at both Time 1 and Time 2. Path analysis via structural equation modeling suggested that sibling affection was longitudinally and positively related to self-regulation and prosocial behaviors, and negatively related to externalizing behaviors; while sibling hostility was positively, and having a sister was negatively related to internalizing behaviors (in general, paths were stronger for adolescents from two- vs. single-parent families). There was also evidence that adolescents' self-regulation partially mediated the relation between sibling affection and positive and negative adolescent outcomes. The discussion focuses on the importance of continued research examining the mechanisms through which the sibling relationship influences development during adolescence.

Cognitive components of self esteem for individuals with severe mental illness.

PubMed

Blankertz, L

2001-10-01

In a sample of 182 individuals with severe mental illness, the applicability of reflected appraisals and self-enhancement theories as explanations for global self-esteem was examined at two time points on components of stigma, mastery, overall functioning, education, and job prestige. Path analysis demonstrated that the two theories work independently; and that stigma, mastery, and overall functioning are significant, persist over time, and have an enduring effect on self-esteem.

Arrival Time Tracking of Partially Resolved Acoustic Rays with Application to Ocean Acoustic Tomography

DTIC Science & Technology

1991-03-01

ocean acoustic tomography. A straightforward method of arrival time estimation, based on locating the maximum value of an interpolated arrival, was...used with limited success for analysis of data from the December 1988 Monterey Bay Tomography Experiment. Close examination of the data revealed multiple...estimation of arrival times along an ocean acoustic ray path is an important component of ocean acoustic tomography. A straightforward method of arrival time

Path attenuation statistics influenced by orientation of rain cells

NASA Technical Reports Server (NTRS)

Goldhirsh, J.

1976-01-01

The influence of path azimuth on fade and space diversity statistics associated with propagation along earth-satellite paths at a frequency of 18 GHz is examined. A radar rain reflectivity data base obtained during the summer of 1973 is injected into a modeling program and the attenuation along parallel earth-satellite paths are obtained for a conglomeration of azimuths. Statistics are separated into two groupings: one pertaining to earth-satellite paths oriented in the northwest-southeast and the other in the northeast-southwest quadrants using a fixed elevation angle of 45 deg. The latter case shows fading to be greater with a degraded space diversity suggesting rain cells to be elongated along this direction. Cell dimensions are analyzed for both sets of quadrants and are found to have average values larger by 2 km in the northeast-southwest quadrants; a result consistent with the fade and space diversity results. Examination of the wind direction for the 14 rain days of data analyzed shows good correlation of the average or median wind directions with the directions of maximum fading and degraded space diversity.

RADC SCAT automated sneak circuit analysis tool

NASA Astrophysics Data System (ADS)

Depalma, Edward L.

The sneak circuit analysis tool (SCAT) provides a PC-based system for real-time identification (during the design phase) of sneak paths and design concerns. The tool utilizes an expert system shell to assist the analyst so that prior experience with sneak analysis is not necessary for performance. Both sneak circuits and design concerns are targeted by this tool, with both digital and analog circuits being examined. SCAT focuses the analysis at the assembly level, rather than the entire system, so that most sneak problems can be identified and corrected by the responsible design engineer in a timely manner. The SCAT program identifies the sneak circuits to the designer, who then decides what course of action is necessary.

Ultrasonic Phased Array Assessment of the Interference Fit and Leak Path of the North Anna Unit 2 Control Rod Drive Mechanism Nozzle 63 with Destructive Validation

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

Crawford, Susan L.; Cinson, Anthony D.; MacFarlan, Paul J.

2012-08-01

The objective of this investigation was to evaluate the efficacy of ultrasonic testing (UT) for primary water leak path assessments of reactor pressure vessel (RPV) upper head penetrations. Operating reactors have experienced leakage when stress corrosion cracking of nickel-based alloy penetrations allowed primary water into the annulus of the interference fit between the penetration and the low-alloy steel RPV head. In this investigation, UT leak path data were acquired for an Alloy 600 control rod drive mechanism nozzle penetration, referred to as Nozzle 63, which was removed from the North Anna Unit 2 reactor when the RPV head was replacedmore » in 2002. In-service inspection prior to the head replacement indicated that Nozzle 63 had a probable leakage path through the interference fit region. Nozzle 63 was examined using a phased-array UT probe with a 5.0-MHz, eight-element annular array. Immersion data were acquired from the nozzle inner diameter surface. The UT data were interpreted by comparing to responses measured on a mockup penetration with known features. Following acquisition of the UT data, Nozzle 63 was destructively examined to determine if the features identified in the UT examination, including leakage paths and crystalline boric acid deposits, could be visually confirmed. Additional measurements of boric acid deposit thickness and low-alloy steel wastage were made to assess how these factors affect the UT response. The implications of these findings for interpreting UT leak path data are described.« less

Multispectral scanner system parameter study and analysis software system description, volume 2

NASA Technical Reports Server (NTRS)

Landgrebe, D. A. (Principal Investigator); Mobasseri, B. G.; Wiersma, D. J.; Wiswell, E. R.; Mcgillem, C. D.; Anuta, P. E.

1978-01-01

The author has identified the following significant results. The integration of the available methods provided the analyst with the unified scanner analysis package (USAP), the flexibility and versatility of which was superior to many previous integrated techniques. The USAP consisted of three main subsystems; (1) a spatial path, (2) a spectral path, and (3) a set of analytic classification accuracy estimators which evaluated the system performance. The spatial path consisted of satellite and/or aircraft data, data correlation analyzer, scanner IFOV, and random noise model. The output of the spatial path was fed into the analytic classification and accuracy predictor. The spectral path consisted of laboratory and/or field spectral data, EXOSYS data retrieval, optimum spectral function calculation, data transformation, and statistics calculation. The output of the spectral path was fended into the stratified posterior performance estimator.

Paths with more turns are perceived as longer: misperceptions with map-based and abstracted path stimuli.

PubMed

Brunyé, Tad T; Mahoney, Caroline R; Taylor, Holly A

2015-04-01

When navigating, people tend to overestimate distances when routes contain more turns, termed the route-angularity effect. Three experiments examined the source and generality of this effect. The first two experiments examined whether route-angularity effects occur while viewing maps and might be related to sex differences or sense of direction. The third experiment tested whether the route-angularity effect would occur with stimuli devoid of spatial context, reducing influences of environmental experience and visual complexity. In the three experiments, participants (N=1,552; M=32.2 yr.; 992 men, 560 women) viewed paths plotted on maps (Exps. 1 and 2) or against a blank background (Exp. 3). The depicted paths were always the same overall length, but varied in the number of turns (from 1 to 7) connecting an origin and destination. Participants were asked to estimate the time to traverse each path (Exp. 1) or the length of each path (Exps. 2 and 3). The Santa Barbara Sense of Direction questionnaire was administered to assess whether overall spatial sense of direction would be negatively related to the magnitude of the route-angularity effect. Repeated-measures analyses of variance (ANOVAs) indicated that paths with more turns elicited estimates of greater distance and travel times, whether they were depicted on maps or blank backgrounds. Linear regressions also indicated that these effects were significantly larger in those with a relatively low sense of direction. The results support the route-angularity effect and extend it to paths plotted on map-based stimuli. Furthermore, because the route-angularity effect was shown with paths plotted against blank backgrounds, route-angularity effects are not specific to understanding environments and may arise at the level of visual perception.

In Praise of Ignorance

ERIC Educational Resources Information Center

Formica, Piero

2014-01-01

In this article Piero Formica examines the difference between incremental and revolutionary innovation, distinguishing between the constrained "path finders" and the unconstrained "path creators". He argues that an acceptance of "ignorance" and a willingness to venture into the unknown are critical elements in…

Life events, anxiety, social support, personality, and alexithymia in female patients with chronic pain: A path analysis.

PubMed

Zeng, Fanmin; Sun, Xueli; Yang, Bangxiang; Fu, Xiaoqian

2016-03-01

This study sought to identify a model that explains the relationship between psychosocial factors and chronic pain in female patients, and to explore all of these constructs in a single study and provide a more holistic examination of the overall psychosocial factors that female patients with chronic pain encounter. Female patients with chronic pain (n = 147), aged 20-65 (M = 34.9 years, SD = 11.25), from an outpatient pain clinic completed a cross-sectional self-report questionnaire on anxiety, life events, personality, social support, and alexithymia. Data were analyzed by means of path analysis. The direct effect of anxiety on female patients with chronic pain was greatest among all the paths. Personality and alexithymia led to chronic pain in female patients only indirectly, mediated by life events. The personality factors of neuroticism and extraversion were associated positively with social support, which had an indirect effect on the influence of life events on chronic pain. However, alexithymia was associated negatively with social support, which had an indirect effect on the influence of life events on chronic pain. Our findings provide evidence that life events are a mediator in the relationship between personality, social support, alexithymia, and chronic pain in female patients. © 2015 The Authors. Asia-Pacific Psychiatry published by Wiley Publishing Asia Pty Ltd.

Low self-esteem and hopelessness in childhood and suicidal ideation in early adulthood.

PubMed

McGee, R; Williams, S; Nada-Raja, S

2001-08-01

This study examined the longitudinal relationship between family characteristics in early childhood. self-esteem, hopelessness and thoughts of self-harm in the midchildhood years, and suicidal ideation at ages 18 and 21. Path analysis was used to establish separate models for boys and girls. The results suggested different pathways to later suicidal ideation for boys and girls. For boys, suicidal ideation seemed to have stronger roots in childhood, with significant paths from low self-esteem and hopelessness to early thoughts of self-harm and thence to later ideation. For girls, self-esteem had a small but significant direct effect on later suicidal ideation. The findings provide support for the idea that individual characteristics such as feelings of hopelessness and low self-esteem act as "generative mechanisms," linking early childhood family characteristics to suicidal ideation in early adulthood.

An Introduction to Path Analysis

ERIC Educational Resources Information Center

Wolfe, Lee M.

1977-01-01

The analytical procedure of path analysis is described in terms of its use in nonexperimental settings in the social sciences. The description assumes a moderate statistical background on the part of the reader. (JKS)

Hierarchy of Dysfunction Related to Dressing Performance in Stroke Patients: A Path Analysis Study.

PubMed

Fujita, Takaaki; Nagayama, Hirofumi; Sato, Atsushi; Yamamoto, Yuichi; Yamane, Kazuhiro; Otsuki, Koji; Tsuchiya, Kenji; Tozato, Fusae

2016-01-01

Previous reports indicated that various dysfunctions caused by stroke affect the level of independence in dressing. These dysfunctions can be hierarchical, and these effects on dressing performance can be complicated in stroke patients. However, there are no published reports focusing on the hierarchical structure of the relationships between the activities of daily living and balance function, motor and sensory functions of the affected lower limb, strength of the abdominal muscles and knee extension on the unaffected side, and visuospatial deficits. The purpose of this study was to elucidate the hierarchical and causal relationships between dressing performance and these dysfunctions in stroke patients. This retrospective study included 104 first-time stroke patients. The causal relationship between the dressing performance and age, time post stroke, balance function, motor and sensory functions of the affected lower limb, strength of the abdominal muscles and knee extension on the unaffected side, and visuospatial deficits were examined using path analysis. A hypothetical path model was created based on previous studies, and the goodness of fit between the data and model were verified. A modified path model was created that achieved an almost perfect fit to the data. Balance function and abdominal muscle strength have direct effects on dressing performance, with standardized direct effect estimates of 0.78 and 0.15, respectively. Age, motor and sensory functions of the affected lower limb, and strength of abdominal muscle and knee extension on the unaffected side have indirect effects on dressing by influencing balance function. Our results suggest that dressing performance depends strongly on balance function, and it is mainly influenced by the motor function of the affected lower limb.

Interweaving interactions in virtual worlds: a case study.

PubMed

Cantamesse, Matteo; Galimberti, Carlo; Giacoma, Gianandrea

2011-01-01

The aim of this study was to examine the effect of playing the online game World of Warcraft (WoW), both on adolescent's (effective) social interaction and on the competence they developed on it. Social interactions within the game environment have been investigated by integrating qualitative and quantitative methods: conversation analysis and social network analysis (SNA). From a psychosocial point of view, the in-game interactions, and in particular conversational exchanges, turn out to be a collaborative path of the joint definition of identities and social ties, with reflection on in-game processes and out-game relationship.

Improving The Performance of Customer Loyalty of Online Ticketing in Indonesia's Showbiz Industry

NASA Astrophysics Data System (ADS)

Dachyar, M.; Athory, E. S.

2015-06-01

Currently the entertainment industry is adopting online ticketing for supporting business from main products to profitability improvement. E-loyalty needs to be examined because are deals with less loyal customer characteristic. The sample are 249 customers whom have purchased for tickets online at least once. Data was gathered by questionnaires and analyzed by Path Analysis and Importance - Performance Analysis. The findings of the research indicate that satisfaction has the strongest relationship to e-loyalty. This study provides four improvement alternatives as a form of new business development strategy for showbiz industry in Indonesia.

JPL-ANTOPT antenna structure optimization program

NASA Technical Reports Server (NTRS)

Strain, D. M.

1994-01-01

New antenna path-length error and pointing-error structure optimization codes were recently added to the MSC/NASTRAN structural analysis computer program. Path-length and pointing errors are important measured of structure-related antenna performance. The path-length and pointing errors are treated as scalar displacements for statics loading cases. These scalar displacements can be subject to constraint during the optimization process. Path-length and pointing-error calculations supplement the other optimization and sensitivity capabilities of NASTRAN. The analysis and design functions were implemented as 'DMAP ALTERs' to the Design Optimization (SOL 200) Solution Sequence of MSC-NASTRAN, Version 67.5.

A Path Analysis of Latino Parental, Teenager and Cultural Variables in Teenagers' Sexual Attitudes, Norms, Self-Efficacy, and Sexual Intentions.

PubMed

Gaioso, Vanessa Pirani; Villarruel, Antonia Maria; Wilson, Lynda Anne; Azuero, Andres; Childs, Gwendolyn Denice; Davies, Susan Lane

2015-01-01

to test a theoretical model based on the Parent-Based Expansion of the Theory of Planned Behavior examining relation between selected parental, teenager and cultural variables and Latino teenagers' intentions to engage in sexual behavior. a cross-sectional correlational design based on a secondary data analysis of 130 Latino parent and teenager dyads. regression and path analysis procedures were used to test seven hypotheses and the results demonstrated partial support for the model. Parent familism and knowledge about sex were significantly associated with parents' attitudes toward sexual communication with their teenagers. Parent Latino acculturation was negatively associated with parents' self-efficacy toward sexual communication with their teenagers and positevely associated with parents' subjective norms toward sexual communication with their teenagers. Teenager knowledge about sex was significantly associated with higher levels of teenagers' attitudes and subjective norms about sexual communication with parents. Only the predictor of teenagers' attitudes toward having sex in the next 3 months was significantly associated with teenagers' intentions to have sex in the next 3 months. the results of this study provide important information to guide future research that can inform development of interventions to prevent risky teenager sexual behavior among Latinos.

Intimate partner violence in the eastern part of Iran: a path analysis of risk factors.

PubMed

Moghaddam Hosseini, Vahideh; Asadi, Zahra Sadat; Akaberi, Arash; Hashemian, Masoumeh

2013-08-01

Intimate partner violence against women is a widespread phenomenon that is the cause of many deleterious health and social consequences. This study examines the impact of some risk factors on partner violence in the eastern region of Iran, using path analysis. The study used a population-based cross sectional study design. In this study, 251 married women who were referred to the health centers were selected through a proportionally stratified and randomized sampling method. Domestic violence was measured using Conflict Tactics Scale and the socio-demographic variable was assessed by a self-report questionnaire. Bayesian Structural Equation Modeling was used for evaluating the overall path analysis and the direct and indirect p-value was estimated by Bootstrap method. AMOS and SPSS software were used to analyze data. The prevalence of overall violence was 78.1%, with 37.8% and 0.8% of women reporting minor and severe violence, respectively, and 39.8% reporting both severe and minor forms of violence. Psychological violence was the most common type of violence reported (66.5%). The model showed that husbands' drug abuse and women's higher level of education compared to their husbands were the first and second most important factors that significantly and directly influenced the violence. The women's attitude, however, had the least effect on the violence. The findings indicated that higher educated women and women with addicted husbands were more likely to experience violence. Treating the drug abuse disorders, especially mental disorders, using behavioral couple's therapy, as well as modifying certain traditional and cultural biases against women's empowerment are suggested.

Generalized causal mediation and path analysis: Extensions and practical considerations.

PubMed

Albert, Jeffrey M; Cho, Jang Ik; Liu, Yiying; Nelson, Suchitra

2018-01-01

Causal mediation analysis seeks to decompose the effect of a treatment or exposure among multiple possible paths and provide casually interpretable path-specific effect estimates. Recent advances have extended causal mediation analysis to situations with a sequence of mediators or multiple contemporaneous mediators. However, available methods still have limitations, and computational and other challenges remain. The present paper provides an extended causal mediation and path analysis methodology. The new method, implemented in the new R package, gmediation (described in a companion paper), accommodates both a sequence (two stages) of mediators and multiple mediators at each stage, and allows for multiple types of outcomes following generalized linear models. The methodology can also handle unsaturated models and clustered data. Addressing other practical issues, we provide new guidelines for the choice of a decomposition, and for the choice of a reference group multiplier for the reduction of Monte Carlo error in mediation formula computations. The new method is applied to data from a cohort study to illuminate the contribution of alternative biological and behavioral paths in the effect of socioeconomic status on dental caries in adolescence.

A systematic investigation of navigation impairment in chronic stroke patients: Evidence for three distinct types.

PubMed

Claessen, Michiel H G; Visser-Meily, Johanna M A; Meilinger, Tobias; Postma, Albert; de Rooij, Nicolien K; van der Ham, Ineke J M

2017-08-01

In a recent systematic review, Claessen and van der Ham (2017) have analyzed the types of navigation impairment in the single-case study literature. Three dissociable types related to landmarks, locations, and paths were identified. This recent model as well as previous models of navigation impairment have never been verified in a systematic manner. The aim of the current study was thus to investigate the prevalence of landmark-based, location-based, and path-based navigation impairment in a large sample of stroke patients. Navigation ability of 77 stroke patients in the chronic phase and 60 healthy participants was comprehensively evaluated using the Virtual Tübingen test, which contains twelve subtasks addressing various aspects of knowledge about landmarks, locations, and paths based on a newly learned virtual route. Participants also filled out the Wayfinding Questionnaire to allow for making a distinction between stroke patients with and without significant subjective navigation-related complaints. Analysis of responses on the Wayfinding Questionnaire indicated that 33 of the 77 participating stroke patients had significant navigation-related complaints. An examination of their performance on the Virtual Tübingen test established objective evidence for navigation impairment in 27 patients. Both landmark-based and path-based navigation impairment occurred in isolation, while location-based navigation impairment was only found along with the other two types. The current study provides the first empirical support for the distinction between landmark-based, location-based, and path-based navigation impairment. Future research relying on other assessment instruments of navigation ability might be helpful to further validate this distinction. Copyright © 2017 Elsevier Ltd. All rights reserved.

The semantic distance task: Quantifying semantic distance with semantic network path length.

PubMed

Kenett, Yoed N; Levi, Effi; Anaki, David; Faust, Miriam

2017-09-01

Semantic distance is a determining factor in cognitive processes, such as semantic priming, operating upon semantic memory. The main computational approach to compute semantic distance is through latent semantic analysis (LSA). However, objections have been raised against this approach, mainly in its failure at predicting semantic priming. We propose a novel approach to computing semantic distance, based on network science methodology. Path length in a semantic network represents the amount of steps needed to traverse from 1 word in the network to the other. We examine whether path length can be used as a measure of semantic distance, by investigating how path length affect performance in a semantic relatedness judgment task and recall from memory. Our results show a differential effect on performance: Up to 4 steps separating between word-pairs, participants exhibit an increase in reaction time (RT) and decrease in the percentage of word-pairs judged as related. From 4 steps onward, participants exhibit a significant decrease in RT and the word-pairs are dominantly judged as unrelated. Furthermore, we show that as path length between word-pairs increases, success in free- and cued-recall decreases. Finally, we demonstrate how our measure outperforms computational methods measuring semantic distance (LSA and positive pointwise mutual information) in predicting participants RT and subjective judgments of semantic strength. Thus, we provide a computational alternative to computing semantic distance. Furthermore, this approach addresses key issues in cognitive theory, namely the breadth of the spreading activation process and the effect of semantic distance on memory retrieval. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Multiscale Path Metrics for the Analysis of Discrete Geometric Structures

DTIC Science & Technology

2017-11-30

Report: Multiscale Path Metrics for the Analysis of Discrete Geometric Structures The views, opinions and/or findings contained in this report are those...Analysis of Discrete Geometric Structures Report Term: 0-Other Email: tomasi@cs.duke.edu Distribution Statement: 1-Approved for public release

Statistical Symbolic Execution with Informed Sampling

NASA Technical Reports Server (NTRS)

Filieri, Antonio; Pasareanu, Corina S.; Visser, Willem; Geldenhuys, Jaco

2014-01-01

Symbolic execution techniques have been proposed recently for the probabilistic analysis of programs. These techniques seek to quantify the likelihood of reaching program events of interest, e.g., assert violations. They have many promising applications but have scalability issues due to high computational demand. To address this challenge, we propose a statistical symbolic execution technique that performs Monte Carlo sampling of the symbolic program paths and uses the obtained information for Bayesian estimation and hypothesis testing with respect to the probability of reaching the target events. To speed up the convergence of the statistical analysis, we propose Informed Sampling, an iterative symbolic execution that first explores the paths that have high statistical significance, prunes them from the state space and guides the execution towards less likely paths. The technique combines Bayesian estimation with a partial exact analysis for the pruned paths leading to provably improved convergence of the statistical analysis. We have implemented statistical symbolic execution with in- formed sampling in the Symbolic PathFinder tool. We show experimentally that the informed sampling obtains more precise results and converges faster than a purely statistical analysis and may also be more efficient than an exact symbolic analysis. When the latter does not terminate symbolic execution with informed sampling can give meaningful results under the same time and memory limits.

An Optimization-Driven Analysis Pipeline to Uncover Biomarkers and Signaling Paths: Cervix Cancer.

PubMed

Lorenzo, Enery; Camacho-Caceres, Katia; Ropelewski, Alexander J; Rosas, Juan; Ortiz-Mojer, Michael; Perez-Marty, Lynn; Irizarry, Juan; Gonzalez, Valerie; Rodríguez, Jesús A; Cabrera-Rios, Mauricio; Isaza, Clara

2015-06-01

Establishing how a series of potentially important genes might relate to each other is relevant to understand the origin and evolution of illnesses, such as cancer. High-throughput biological experiments have played a critical role in providing information in this regard. A special challenge, however, is that of trying to conciliate information from separate microarray experiments to build a potential genetic signaling path. This work proposes a two-step analysis pipeline, based on optimization, to approach meta-analysis aiming to build a proxy for a genetic signaling path.

FEAR OF PAST ABUSIVE PARTNER(S) IMPACTS CURRENT POSTTRAUMATIC STRESS AMONG WOMEN EXPERIENCING PARTNER VIOLENCE

PubMed Central

Jaquier, Véronique; Sullivan, Tami P.

2014-01-01

This study examines the impact of fear of past abusive partner(s) on posttraumatic stress among 212 community-recruited women currently exposed to intimate partner violence (IPV). The path analysis model tested explained 60% of the variation in IPV-related posttraumatic stress. Findings revealed that fear of past abusive partner(s) was uniquely associated with the severity of current posttraumatic stress symptoms over and above the impact of current IPV or childhood abuse and neglect. Future research should continue examining women's subjective emotional experience of past and current victimization so as to further inform both clinical practice and intervention planning. PMID:24590514

Changes in triglycerides and high-density lipoprotein cholesterol may precede peripheral insulin resistance, with 2-h insulin partially mediating this unidirectional relationship: a prospective cohort study.

PubMed

Han, Tianshu; Cheng, Yu; Tian, Shuang; Wang, Li; Liang, Xi; Duan, Wei; Na, Lixin; Sun, Changhao

2016-11-04

Results of longitudinal researches regarding the temporal relationship between dyslipidemia and insulin resistance (IR) are inconsistent. This study assessed temporal relationships of blood lipids with IR and determined whether there are any mediating effects existed in these temporal relationships. This study examined a longitudinal cohort of 3325 subjects aged 20-74 years from China with an average of 4.2 years follow-up. Measurements of fasting blood lipids, as well as fasting and 2-h serum glucose and insulin, were obtained at two time points. The Gutt index and HOMA-IR were calculated as indicators of peripheral IR and hepatic IR. A cross-lagged path analysis was performed to examine the temporal relationships between blood lipids and IR. A mediation analysis was used to examine mediating effect. After adjusting for covariates, the cross-lagged path coefficients from baseline TG and HDL-C to follow-up Gutt index were significantly greater than those from baseline Gutt index to follow-up TG and HDL-C (β 1  = -0.131 vs β 2  = -0.047, P < 0.001 for TG; β 1  = 0.134 vs β 2  = 0.023, P < 0.001 for HDL-C). The path coefficients from baseline TG and HDL-C to follow-up 2-h insulin were significantly greater than those from baseline 2-h insulin to follow-up TG and HDL-C (β 1  = 0.125 vs β 2  = 0.040, P < 0.001 for TG; β 1  = -0.112 vs β 2  = -0.026, P < 0.001 for HDL-C). 2-h insulin partially mediated the effect of TG/HDL-C on Gutt index with a 59.3% mediating effect for TG and 61.0% for HDL-C. These findings provide strong evidence that dyslipidemia probably precede peripheral IR and that 2-h insulin partially mediates this unidirectional temporal relationship.

A flight investigation with a STOL airplane flying curved, descending instrument approach paths

NASA Technical Reports Server (NTRS)

Benner, M. S.; Mclaughlin, M. D.; Sawyer, R. H.; Vangunst, R.; Ryan, J. L.

1974-01-01

A flight investigation using a De Havilland Twin Otter airplane was conducted to determine the configurations of curved, 6 deg descending approach paths which would provide minimum airspace usage within the requirements for acceptable commercial STOL airplane operations. Path configurations with turns of 90 deg, 135 deg, and 180 deg were studied; the approach airspeed was 75 knots. The length of the segment prior to turn, the turn radius, and the length of the final approach segment were varied. The relationship of the acceptable path configurations to the proposed microwave landing system azimuth coverage requirements was examined.

Visualizing Transmedia Networks: Links, Paths and Peripheries

ERIC Educational Resources Information Center

Ruppel, Marc Nathaniel

2012-01-01

'Visualizing Transmedia Networks: Links, Paths and Peripheries' examines the increasingly complex rhetorical intersections between narrative and media ("old" and "new") in the creation of transmedia fictions, loosely defined as multisensory and multimodal stories told extensively across a diverse media set. In order…

TCP Packet Trace Analysis. M.S. Thesis

NASA Technical Reports Server (NTRS)

Shepard, Timothy J.

1991-01-01

Examination of a trace of packets collected from the network is often the only method available for diagnosing protocol performance problems in computer networks. This thesis explores the use of packet traces to diagnose performance problems of the transport protocol TCP. Unfortunately, manual examination of these traces can be so tedious that effective analysis is not possible. The primary contribution of this thesis is a graphical method of displaying the packet trace which greatly reduce, the tediousness of examining a packet trace. The graphical method is demonstrated by the examination of some packet traces of typical TCP connections. The performance of two different implementations of TCP sending data across a particular network path is compared. Traces many thousands of packets long are used to demonstrate how effectively the graphical method simplifies examination of long complicated traces. In the comparison of the two TCP implementations, the burstiness of the TCP transmitter appeared to be related to the achieved throughput. A method of quantifying this burstiness is presented and its possible relevance to understanding the performance of TCP is discussed.

Analysis of crossing path crashes

DOT National Transportation Integrated Search

2001-07-01

This report defines the problem of crossing path crashes in the United States. This crash type involves one moving vehicle that cuts across the path of another when their initial approach comes from either lateral or opposite directions and they typi...

Analysis of factors controlling soil phosphorus loss with surface runoff in Huihe National Nature Reserve by principal component and path analysis methods.

PubMed

He, Jing; Su, Derong; Lv, Shihai; Diao, Zhaoyan; Bu, He; Wo, Qiang

2018-01-01

Phosphorus (P) loss with surface runoff accounts for the P input to and acceleration of eutrophication of the freshwater. Many studies have focused on factors affecting P loss with surface runoff from soils, but rarely on the relationship among these factors. In the present study, rainfall simulation on P loss with surface runoff was conducted in Huihe National Nature Reserve, in Hulunbeier grassland, China, and the relationships between P loss with surface runoff, soil properties, and rainfall conditions were examined. Principal component analysis and path analysis were used to analyze the direct and indirect effects on P loss with surface runoff. The results showed that P loss with surface runoff was closely correlated with soil electrical conductivity, soil pH, soil Olsen P, soil total nitrogen (TN), soil total phosphorus (TP), and soil organic carbon (SOC). The main driving factors which influenced P loss with surface runoff were soil TN, soil pH, soil Olsen P, and soil water content. Path analysis and determination coefficient analysis indicated that the standard multiple regression equation for P loss with surface runoff and each main factor was Y = 7.429 - 0.439 soil TN - 6.834 soil pH + 1.721 soil Olsen-P + 0.183 soil water content (r = 0.487, p < 0.01, n = 180). Soil TN, soil pH, soil Olsen P, and soil water content and the interactions between them were the main factors affecting P loss with surface runoff. The effect of physical and chemical properties of undisturbed soils on P loss with surface runoff was discussed, and the soil water content and soil Olsen P were strongly positive influences on the P loss with surface runoff.

Conflicting relationship between age-dependent disorders, valvular heart disease and coronary artery disease by covariance structure analysis: Possible contribution of natriuretic peptide.

PubMed

Fukumoto, Risa; Kawai, Makoto; Minai, Kosuke; Ogawa, Kazuo; Yoshida, Jun; Inoue, Yasunori; Morimoto, Satoshi; Tanaka, Toshikazu; Nagoshi, Tomohisa; Ogawa, Takayuki; Yoshimura, Michihiro

2017-01-01

It is conceivable that contemporary valvular heart disease (VHD) is affected largely by an age-dependent atherosclerotic process, which is similar to that observed in coronary artery disease (CAD). However, a comorbid condition of VHD and CAD has not been precisely examined. The first objective of this study was to examine a possible comorbid condition. Provided that there is no comorbidity, the second objective was to search for the possible reasons by using conventional risk factors and plasma B-type natriuretic peptide (BNP) because BNP has a potentiality to suppress atherosclerotic development. The study population consisted of 3,457 patients consecutively admitted to our institution. The possible comorbid condition of VHD and CAD and the factors that influence the comorbidity were examined by covariance structure analysis and multivariate analysis. The distribution of the patients with VHD and those with CAD in the histograms showed that the incidence of VHD and the severity of CAD rose with seniority in appearance. The real statistical analysis was planned by covariance structure analysis. The current path model revealed that aging was associated with VHD and CAD severity (P < 0.001 for each); however, as a notable result, there was an inverse association regarding the comorbid condition between VHD and CAD (Correlation coefficient [β]: -0.121, P < 0.001). As the second objective, to clarify the factors leading to this inverse association, the contribution of conventional risk factors, such as age, gender, hypertension, smoking, diabetes, obesity and dyslipidemia, to VHD and CAD were examined by multivariate analysis. However, these factors did not exert an opposing effect on VHD and CAD, and the inverse association defied explanation. Since different pathological mechanisms may contribute to the formation of VHD and CAD, a differentially proposed path model using plasma BNP revealed that an increase in plasma BNP being drawn by VHD suppressed the progression of CAD (β: -0.465, P < 0.001). The incidence of VHD and CAD showed a significant conflicting relationship. This result supported the likely presence of unknown diverse mechanisms on top of the common cascade of atherosclerosis. Among them, the continuous elevation of plasma BNP due to VHD might be one of the explicable factors suppressing the progression of CAD.

Development and Demonstration of an Ada Test Generation System

NASA Technical Reports Server (NTRS)

1996-01-01

In this project we have built a prototype system that performs Feasible Path Analysis on Ada programs: given a description of a set of control flow paths through a procedure, and a predicate at a program point feasible path analysis determines if there is input data which causes execution to flow down some path in the collection reaching the point so that tile predicate is true. Feasible path analysis can be applied to program testing, program slicing, array bounds checking, and other forms of anomaly checking. FPA is central to most applications of program analysis. But, because this problem is formally unsolvable, syntactic-based approximations are used in its place. For example, in dead-code analysis the problem is to determine if there are any input values which cause execution to reach a specified program point. Instead an approximation to this problem is computed: determine whether there is a control flow path from the start of the program to the point. This syntactic approximation is efficiently computable and conservative: if there is no such path the program point is clearly unreachable, but if there is such a path, the analysis is inconclusive, and the code is assumed to be live. Such conservative analysis too often yields unsatisfactory results because the approximation is too weak. As another example, consider data flow analysis. A du-pair is a pair of program points such that the first point is a definition of a variable and the second point a use and for which there exists a definition-free path from the definition to the use. The sharper, semantic definition of a du-pair requires that there be a feasible definition-free path from the definition to the use. A compiler using du-pairs for detecting dead variables may miss optimizations by not considering feasibility. Similarly, a program analyzer computing program slices to merge parallel versions may report conflicts where none exist. In the context of software testing, feasibility analysis plays an important role in identifying testing requirements which are infeasible. This is especially true for data flow testing and modified condition/decision coverage. Our system uses in an essential way symbolic analysis and theorem proving technology, and we believe this work represents one of the few successful uses of a theorem prover working in a completely automatic fashion to solve a problem of practical interest. We believe this work anticipates an important trend away from purely syntactic-based methods for program analysis to semantic methods based on symbolic processing and inference technology. Other results demonstrating the practical use of automatic inference is being reported in hardware verification, although there are significant differences between the hardware work and ours. However, what is common and important is that general purpose theorem provers are being integrated with more special-purpose decision procedures to solve problems in analysis and verification. We are pursuina commercial opportunities for this work, and will use and extend the work in other projects we are engaged in. Ultimately we would like to rework the system to analyze C, C++, or Java as a key step toward commercialization.

Assessment of resuspended matter and redistribution of macronutrient elements produced by boat disturbance in a eutrophic lagoon.

PubMed

Lenzi, Mauro; Finoia, Maria Grazia; Gennaro, Paola; Mercatali, Isabel; Persia, Emma; Solari, Jacopo; Porrello, Salvatore

2013-07-15

Harvesting of macroalgae by specially equipped boats in a shallow eutrophic lagoon produces evident sediment resuspension. To outline the environmental effects of this disturbance, we examined the quantity of fall-out and the distances travelled by sediment and macronutrients from the source of boat disturbance. Resuspended sediment fall-out (RSFO) was trapped at different distances from the boat path to determine total dry weight, total nitrogen (TN), total carbon (TC), total organic carbon (TOC), total sulphur (TS) and total phosphorus (TP). The data was analysed by principal components analysis (PCA) and linear discriminant analysis (LDA) on PCA factors. Fall-out of C, N, S and P from the plume of resuspended sediment indicated significant re-arrangement of these nutrients: RSFO dry weight and S content decreased with distance from the boat path, whereas TP increased and was the variable responsible for most discrimination at 100 m. The mass of resuspended matter was relatively large, indicating that the boats considerably reshuffle lagoon sediment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Efficient micromagnetics for magnetic storage devices

NASA Astrophysics Data System (ADS)

Escobar Acevedo, Marco Antonio

Micromagnetics is an important component for advancing the magnetic nanostructures understanding and design. Numerous existing and prospective magnetic devices rely on micromagnetic analysis, these include hard disk drives, magnetic sensors, memories, microwave generators, and magnetic logic. The ability to examine, describe, and predict the magnetic behavior, and macroscopic properties of nanoscale magnetic systems is essential for improving the existing devices, for progressing in their understanding, and for enabling new technologies. This dissertation describes efficient micromagnetic methods as required for magnetic storage analysis. Their performance and accuracy is demonstrated by studying realistic, complex, and relevant micromagnetic system case studies. An efficient methodology for dynamic micromagnetics in large scale simulations is used to study the writing process in a full scale model of a magnetic write head. An efficient scheme, tailored for micromagnetics, to find the minimum energy state on a magnetic system is presented. This scheme can be used to calculate hysteresis loops. An efficient scheme, tailored for micromagnetics, to find the minimum energy path between two stable states on a magnetic system is presented. This minimum energy path is intimately related to the thermal stability.

Graph theory applied to noise and vibration control in statistical energy analysis models.

PubMed

Guasch, Oriol; Cortés, Lluís

2009-06-01

A fundamental aspect of noise and vibration control in statistical energy analysis (SEA) models consists in first identifying and then reducing the energy flow paths between subsystems. In this work, it is proposed to make use of some results from graph theory to address both issues. On the one hand, linear and path algebras applied to adjacency matrices of SEA graphs are used to determine the existence of any order paths between subsystems, counting and labeling them, finding extremal paths, or determining the power flow contributions from groups of paths. On the other hand, a strategy is presented that makes use of graph cut algorithms to reduce the energy flow from a source subsystem to a receiver one, modifying as few internal and coupling loss factors as possible.

Analyzing Water's Optical Absorption

NASA Technical Reports Server (NTRS)

2002-01-01

A cooperative agreement between World Precision Instruments (WPI), Inc., and Stennis Space Center has led the UltraPath(TM) device, which provides a more efficient method for analyzing the optical absorption of water samples at sea. UltraPath is a unique, high-performance absorbance spectrophotometer with user-selectable light path lengths. It is an ideal tool for any study requiring precise and highly sensitive spectroscopic determination of analytes, either in the laboratory or the field. As a low-cost, rugged, and portable system capable of high- sensitivity measurements in widely divergent waters, UltraPath will help scientists examine the role that coastal ocean environments play in the global carbon cycle. UltraPath(TM) is a trademark of World Precision Instruments, Inc. LWCC(TM) is a trademark of World Precision Instruments, Inc.

Fade Analysis of ORCA DATA Beam at NTTR and Pax River

DTIC Science & Technology

2010-08-01

bit-error-rate (BER) of the data beam on the downlink path. 15 Start Time-PST (Duration) Range Scin Index 1 Rx=5.1cm... Scin Index 2 Rx=13.7cm Scin Index 3 Rx=27.2cm Path Ave Cn2 (m-2/3) Path Ave Inner Scale Path Ave Outer Scale Flight 2 May 16

Three Critical Tasks America's Disadvantaged Face on Their Path to College.

ERIC Educational Resources Information Center

Cabrera, Alberto F.; La Nasa, Steven M.

2000-01-01

Using data from the National Educational Longitudinal Study of 1988, examines the wide disparity of college-choice activities between socioeconomic groups. In order to highlight this disparity, analyzes three tasks that all students must complete on their path to college. (Author/EV)

Relational Influences on Career Paths: Siblings in Context

ERIC Educational Resources Information Center

Schultheiss, Donna E. Palladino; Palma, Thomas V.; Predragovich, Krista S.; Glasscock, Julie M. Jeffrey

2002-01-01

This investigation examined participants' perceptions of sibling relational influence on career exploration and decision making. Career path influence on sibling relationships and times when these relationships were most important also were explored. Individual interviews were conducted with urban commuter college students, and narrative data were…

Structureborne noise investigations of a twin engine aircraft

NASA Technical Reports Server (NTRS)

Garrelick, J. M.; Cole, J. E., III; Martini, K.

1986-01-01

The interior noise of aircraft powered by advanced turbo-prop concepts is likely to have nonnegligible contributions from structureborne paths, these paths being those involving propeller loads transmitted to the structures of the lifting surfaces. As a means of examining these paths, structural measurements have been performed on a small twin-engine aircraft, and in addition analytical models of the structure have been developed. In this paper results from both portions of this study are presented.

The influence of NO and ClO variations at twilight on the interpretation of solar occultation measurements

NASA Technical Reports Server (NTRS)

Boughner, R.; Larsen, J. C.; Natarajan, M.

1980-01-01

Measurement of short-lived photochemically-produced species in the stratosphere by solar occultation is difficult because the rapid variation of such species near the terminator introduces ambiguities in interpreting the measured absorption in terms of meaningful atmospheric abundances. These variations produce tangent path concentrations that are asymmetric relative to the tangent point, as opposed to the symmetrical distribution usually assumed in most inversion algorithms. Neglect of this asymmetry may yield an inverted profile that deviates significantly from the true sunset/sunrise profile. In the present paper, the influence of this effect on solar occultation measurements of ClO and NO is examined. The results show that average inhomogeneity factors, which measure the concentration variation along the tangent path and which can be calculated from a photochemical model, can indicate which species require more careful data analysis.

A longitudinal analysis of burnout in middle and high school Korean teachers.

PubMed

Park, Yang Min; Lee, Sang Min

2013-12-01

This study examines longitudinal relationships among three burnout dimensions in middle and high school teachers. For this study, 419 middle and high school teachers participated in a panel survey, which was conducted in three waves. Using Amos 7.0, we performed autoregressive cross-lagged modeling to obtain a complete picture of the longitudinal relationships among the three factors of the Maslach Burnout Inventory-Educator Survey. Results indicated that the paths from emotional exhaustion at Time1 and Time2 to depersonalization at Time2 and Time3 were statistically significant. In addition, the paths from personal accomplishment at Time1 and Time2 to depersonalization at Time2 and Time3 were also statistically significant. Empirically identifying the process by which burnout occurs could help practitioners and policy makers to design burnout prevention strategies. Copyright © 2012 John Wiley & Sons, Ltd.

Information management: considering adolescents' regulation of parental knowledge.

PubMed

Marshall, Sheila K; Tilton-Weaver, Lauree C; Bosdet, Lara

2005-10-01

Employing Goffman's [(1959). The presentation of self in everyday life. New York: Doubleday and Company] notion of impression management, adolescents' conveyance of information about their whereabouts and activities to parents was assessed employing two methodologies. First, a two-wave panel design with a sample of 121 adolescents was used to test a model of information management incorporating two forms of information regulation (lying and willingness to disclose), adolescents' perception of their parents' knowledge about their activities, and adolescent misconduct. Path analysis was used to examine the model for two forms of misconduct as outcomes: substance use and antisocial behaviours. Fit indices indicate the path models were all good fits to the data. Second, 96 participants' responses to semi-structured questions were analyzed using a qualitative analytic technique. Findings reveal adolescents withhold or divulge information in coordination with their parents, employ impression management techniques, and try to balance safety issues with preservation of the parent-adolescent relationship.

Preserving correlations between trajectories for efficient path sampling

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

Gingrich, Todd R.; Geissler, Phillip L.; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720

2015-06-21

Importance sampling of trajectories has proved a uniquely successful strategy for exploring rare dynamical behaviors of complex systems in an unbiased way. Carrying out this sampling, however, requires an ability to propose changes to dynamical pathways that are substantial, yet sufficiently modest to obtain reasonable acceptance rates. Satisfying this requirement becomes very challenging in the case of long trajectories, due to the characteristic divergences of chaotic dynamics. Here, we examine schemes for addressing this problem, which engineer correlation between a trial trajectory and its reference path, for instance using artificial forces. Our analysis is facilitated by a modern perspective onmore » Markov chain Monte Carlo sampling, inspired by non-equilibrium statistical mechanics, which clarifies the types of sampling strategies that can scale to long trajectories. Viewed in this light, the most promising such strategy guides a trial trajectory by manipulating the sequence of random numbers that advance its stochastic time evolution, as done in a handful of existing methods. In cases where this “noise guidance” synchronizes trajectories effectively, as the Glauber dynamics of a two-dimensional Ising model, we show that efficient path sampling can be achieved for even very long trajectories.« less

Variable system: An alternative approach for the analysis of mediated moderation.

PubMed

Kwan, Joyce Lok Yin; Chan, Wai

2018-06-01

Mediated moderation (meMO) occurs when the moderation effect of the moderator (W) on the relationship between the independent variable (X) and the dependent variable (Y) is transmitted through a mediator (M). To examine this process empirically, 2 different model specifications (Type I meMO and Type II meMO) have been proposed in the literature. However, both specifications are found to be problematic, either conceptually or statistically. For example, it can be shown that each type of meMO model is statistically equivalent to a particular form of moderated mediation (moME), another process that examines the condition when the indirect effect from X to Y through M varies as a function of W. Consequently, it is difficult for one to differentiate these 2 processes mathematically. This study therefore has 2 objectives. First, we attempt to differentiate moME and meMO by proposing an alternative specification for meMO. Conceptually, this alternative specification is intuitively meaningful and interpretable, and, statistically, it offers meMO a unique representation that is no longer identical to its moME counterpart. Second, using structural equation modeling, we propose an integrated approach for the analysis of meMO as well as for other general types of conditional path models. VS, a computer software program that implements the proposed approach, has been developed to facilitate the analysis of conditional path models for applied researchers. Real examples are considered to illustrate how the proposed approach works in practice and to compare its performance against the traditional methods. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Performance analysis of CCSDS path service

NASA Technical Reports Server (NTRS)

Johnson, Marjory J.

1989-01-01

A communications service, called Path Service, is currently being developed by the Consultative Committee for Space Data Systems (CCSDS) to provide a mechanism for the efficient transmission of telemetry data from space to ground for complex space missions of the future. This is an important service, due to the large volumes of telemetry data that will be generated during these missions. A preliminary analysis of performance of Path Service is presented with respect to protocol-processing requirements and channel utilization.

Evaluation of Acoustic Propagation Paths into the Human Head

DTIC Science & Technology

2005-07-25

paths. A 3D finite-element solid mesh was constructed using a digital image database of an adult male head. Finite-element analysis was used to model the...air-borne sound pressure amplitude) via the alternate propagation paths. A 3D finite-element solid mesh was constructed using a digital image database ... database of an adult male head Coupled acoustic-mechanical finite-element analysis (FEA) was used to model the wave propagation through the fluid-solid

Measurements of the global distribution of carbon monoxide in the troposphere

NASA Technical Reports Server (NTRS)

Hinton, R. R.

1982-01-01

Carbon monoxide and methane grab samples were obtained simultaneously with ozone, aerosol, nitric oxide and DACOM CO measurements. Eighty grab samples were collected at various altitudes up to 19,000 ft. along a north-south flight path from Wallops Flight Center, VA to 11 N. CO and CH were analyzed by flame ionization gas chromatography with cryogenic preconcentration. The relationship between CO and O3 concentrated is examined. A comparative analysis between trends in aerosol and CO concentration is performed.

The historical path of evaluation as reflected in the content of Evaluation and Program Planning.

PubMed

Ayob, Abu H; Morell, Jonathan A

2016-10-01

This paper examines the intellectual structure of evaluation by means of citation analysis. By using various article attributes and citation counts in Google Scholar and (Social) Science Citation Index Web of Science, we analyze all articles published in Evaluation and Program Planning from 2000 until 2012. We identify and discuss the characteristics and development of the field as reflected in the history of those citations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simulating Mission Command for Planning and Analysis

DTIC Science & Technology

2015-06-01

mission plan. 14. SUBJECT TERMS Mission Planning, CPM , PERT, Simulation, DES, Simkit, Triangle Distribution, Critical Path 15. NUMBER OF...Battalion Task Force CO Company CPM Critical Path Method DES Discrete Event Simulation FA BAT Field Artillery Battalion FEL Future Event List FIST...management tools that can be utilized to find the critical path in military projects. These are the Critical Path Method ( CPM ) and the Program Evaluation and

Psychological Empowerment Model in Iranian Pregnant Women

PubMed Central

Taghipour, Ali; Sadat Borghei, Narjes; Latifnejad Roudsari, Robab; Keramat, Afsaneh; Jabbari Nooghabi, Hadi

2016-01-01

ABSTRACT Background: Women’s empowerment programs during pregnancy focus primarily on increasing women’s health goals and psychological empowerment has been considered important in most issues related to pregnant mothers’ mental health. Using path analysis, this study aims to examine the direct and indirect components of psychological empowerment of pregnant mothers. Methods: This model-testing study was conducted in Gorgan, northwest of Iran during three months in spring of 2015. Through random cluster sampling, a total number of 160 pregnant women were selected from 10 urban medical centers and clinics as primary centers. We used Spritzer’s Psychological empowerment scale. Suitable sampling based on Nunally and Bernstein was followed in the model. The relationships between the dependent variables were then examined by means of path analysis using Amos 18. Results: The psychological empowerment of pregnant mothers (PEPW) model is impacted by individual factors, such as marriage age and employment, including some subjectively rated factors such as marital satisfaction and experience of violence. The PEPW model was deemed appropriate as optimum conditions indicators of goodness of fit; low index of χ2/df shows little difference between the conceptual model and observed data, while RMSEA value indicated the goodness of fit. Other indicators such as CMIN=0.957, CMIN/DF=0.957, P-CLOSE=0.418, χ2=0.957 and probability level=0.328 the fact that the model is ideal. The mothers’ employment had the highest coefficient in the PEPW path model .731 (0.443, 0.965) bootstrap confidence intervals by 95%, and with a p-value of less than 0.05. Conclusions: The mothers’ employment is the most important factor in psychological empowerment, but it cannot be addressed quickly. Programming to increase marital satisfaction followed by a decrease in family violence and prevention of early marriage are necessary for promotion of psychological empowerment during pregnancy. PMID:27713897

The influence of authentic leadership and empowerment on nurses' relational social capital, mental health and job satisfaction over the first year of practice.

PubMed

Read, Emily A; Laschinger, Heather K S

2015-07-01

To examine a theoretical model testing the effects of authentic leadership, structural empowerment and relational social capital on the mental health and job satisfaction of new graduate nurses over the first year of practice. Relational social capital is an important interpersonal organizational resource that may foster new graduate nurses' workplace well-being and promote retention. Evidence shows that authentic leadership and structural empowerment are key aspects of the work environment that support new graduate nurses; however, the mediating role of relational social capital has yet to be explored. A longitudinal survey design was used to test the hypothesized model. One hundred ninety-one new graduate nurses in Ontario with <2 years of experience completed mail surveys in January-March 2010 and 1 year later in 2011. Path analysis using structural equation modelling was used to test the theoretical model. Participants were mostly female, working full time in medicine/surgery or critical care. All measures demonstrated acceptable reliability and validity. Path analysis results supported our hypothesized model; structural empowerment mediated the relationship between authentic leadership and nurses' relational social capital, which in turn had a negative effect on mental health symptoms and a positive effect on job satisfaction. All indirect paths in the model were significant. By creating structurally empowering work environments, authentic leaders foster relational social capital among new graduate nurses leading to positive health and retention outcomes. © 2015 John Wiley & Sons Ltd.

Non-CO2 Greenhouse Gas Emissions in China 2012: Inventory and Supply Chain Analysis

NASA Astrophysics Data System (ADS)

Zhang, Bo; Zhang, Yaowen; Zhao, Xueli; Meng, Jing

2018-01-01

Reliable inventory information is critical in informing emission mitigation efforts. Using the latest officially released emission data, which is production based, we take a consumption perspective to estimate the non-CO2 greenhouse gas (GHG) emissions for China in 2012. The non-CO2 GHG emissions, which cover CH4, N2O, HFCs, PFCs, and SF6, amounted to 2003.0 Mt. CO2-eq (including 1871.9 Mt. CO2-eq from economic activities), much larger than the total CO2 emissions in some developed countries. Urban consumption (30.1%), capital formation (28.2%), and exports (20.6%) derived approximately four fifths of the total embodied emissions in final demand. Furthermore, the results from structural path analysis help identify critical embodied emission paths and key economic sectors in supply chains for mitigating non-CO2 GHG emissions in Chinese economic systems. The top 20 paths were responsible for half of the national total embodied emissions. Several industrial sectors such as Construction, Production and Supply of Electricity and Steam, Manufacture of Food and Tobacco and Manufacture of Chemicals, and Chemical Products played as the important transmission channels. Examining both production- and consumption-based non-CO2 GHG emissions will enrich our understanding of the influences of industrial positions, final consumption demands, and trades on national non-CO2 GHG emissions by considering the comprehensive abatement potentials in the supply chains.

PathVisio 3: an extendable pathway analysis toolbox.

PubMed

Kutmon, Martina; van Iersel, Martijn P; Bohler, Anwesha; Kelder, Thomas; Nunes, Nuno; Pico, Alexander R; Evelo, Chris T

2015-02-01

PathVisio is a commonly used pathway editor, visualization and analysis software. Biological pathways have been used by biologists for many years to describe the detailed steps in biological processes. Those powerful, visual representations help researchers to better understand, share and discuss knowledge. Since the first publication of PathVisio in 2008, the original paper was cited more than 170 times and PathVisio was used in many different biological studies. As an online editor PathVisio is also integrated in the community curated pathway database WikiPathways. Here we present the third version of PathVisio with the newest additions and improvements of the application. The core features of PathVisio are pathway drawing, advanced data visualization and pathway statistics. Additionally, PathVisio 3 introduces a new powerful extension systems that allows other developers to contribute additional functionality in form of plugins without changing the core application. PathVisio can be downloaded from http://www.pathvisio.org and in 2014 PathVisio 3 has been downloaded over 5,500 times. There are already more than 15 plugins available in the central plugin repository. PathVisio is a freely available, open-source tool published under the Apache 2.0 license (http://www.apache.org/licenses/LICENSE-2.0). It is implemented in Java and thus runs on all major operating systems. The code repository is available at http://svn.bigcat.unimaas.nl/pathvisio. The support mailing list for users is available on https://groups.google.com/forum/#!forum/wikipathways-discuss and for developers on https://groups.google.com/forum/#!forum/wikipathways-devel.

Centre of pressure correlates with pyramid performance in acrobatic gymnastics.

PubMed

Floría, Pablo; Gómez-Landero, Luis Arturo; Harrison, Andrew J

2015-01-01

Acrobatic gymnasts need excellent balance control to execute pyramids where one gymnast is supported by another. The objectives of this study were: (1) to describe balance performance by assessing the centre of pressure displacement in a group of acrobatic gymnasts executing pyramids; (2) to determine the relationship between the parameters describing the centre of pressure oscillations and pyramid score; and (3) to examine the role of each foot in providing a solid base of support to maintain the balance of the pyramid. Sixteen acrobatic gymnasts grouped in pairs performed a Half pyramid and a Straddle pyramid held for 7 s on two force platforms. Path length, variance, range trajectory, and surface area of the centre of pressure of each foot were examined to analyse the balance of the pyramid. The path length was correlated with the pyramid score (Straddle: p = 0.692 [large]; Half: p = 0.407 [moderate]). There were differences in the functions of each leg to maintain balance, with the non-preferred leg supporting a higher weight of the pyramid while the preferred leg performed control movements to maintain balance. The results suggested that quantitative analysis of balance can provide important information on pyramid performance.

Quantifying tight-gas sandstone permeability via critical path analysis

USDA-ARS?s Scientific Manuscript database

Rock permeability has been actively investigated over the past several decades by the geosciences community. However, its accurate estimation still presents significant technical challenges, especially in spatially complex rocks. In this letter, we apply critical path analysis (CPA) to estimate perm...

Slant path rain attenuation and path diversity statistics obtained through radar modeling of rain structure

NASA Technical Reports Server (NTRS)

Goldhirsh, J.

1984-01-01

Single and joint terminal slant path attenuation statistics at frequencies of 28.56 and 19.04 GHz have been derived, employing a radar data base obtained over a three-year period at Wallops Island, VA. Statistics were independently obtained for path elevation angles of 20, 45, and 90 deg for purposes of examining how elevation angles influences both single-terminal and joint probability distributions. Both diversity gains and autocorrelation function dependence on site spacing and elevation angles were determined employing the radar modeling results. Comparisons with other investigators are presented. An independent path elevation angle prediction technique was developed and demonstrated to fit well with the radar-derived single and joint terminal radar-derived cumulative fade distributions at various elevation angles.

Search Path Mapping: A Versatile Approach for Visualizing Problem-Solving Behavior.

ERIC Educational Resources Information Center

Stevens, Ronald H.

1991-01-01

Computer-based problem-solving examinations in immunology generate graphic representations of students' search paths, allowing evaluation of how organized and focused their knowledge is, how well their organization relates to critical concepts in immunology, where major misconceptions exist, and whether proper knowledge links exist between content…

Promoting Social and Emotional Competencies among Young Children in Croatia with Preschool PATHS

ERIC Educational Resources Information Center

Mihic, Josipa; Novak, Miranda; Basic, Josipa; Nix, Robert L.

2016-01-01

Preschool PATHS (Promoting Alternative Thinking Strategies) is an evidence-based universal prevention program focused on promoting children's social and emotional competencies and reducing the likelihood of behaviour problems and negative relationships with peers and teachers. This paper examines changes in the social and emotional competencies of…

Undergraduate Music Program Alumni's Career Path, Retrospective Institutional Satisfaction, and Financial Status

ERIC Educational Resources Information Center

Miksza, Peter; Hime, Lauren

2015-01-01

The purpose of this study was to examine undergraduate music education and performance alumni's career path, retrospective institutional satisfaction, and financial status. Data for this study were drawn from respondents from the 2010 administration of the nationwide, multi-institutional survey conducted by the Strategic National Arts Alumni…

Using Business Theory to Motivate Undergraduate Students in Goal Attainment: An Empirical Assessment and Model for High Level Motivation and Goal Attainment

ERIC Educational Resources Information Center

Anderson, Paul; Griego, Orlando V.; Stevens, Roxanne Helm

2010-01-01

Students at a private university in southern California took part in a study focusing on high level motivation and goal commitment. Using path analysis, this study mapped out two-paths. The first path to motivation and, therefore, goal commitment was through self-efficacy. The second path to goal commitment required a more supportive course.…

Psychological predictors of participation in screening for cognitive impairment among community-dwelling older adults.

PubMed

Harada, Kazuhiro; Lee, Sangyoon; Shimada, Hiroyuki; Lee, Sungchul; Bae, Seongryu; Anan, Yuya; Harada, Kenji; Suzuki, Takao

2017-08-01

Detecting cognitive impairment in the earlier stages is important for preventing or delaying dementia. To develop intervention strategies that promote screening for cognitive impairment, it is essential to identify the modifiable predictors for participation in screening. The present study examined whether participation in screening for cognitive impairment was predicted by the constructs of the health belief model, dementia worry and behavioral intentions to undergo screening among older adults. The study used a prospective design. After a baseline questionnaire survey, participation in screening for cognitive impairment was followed for 6 months (n = 10 023). Participation in the screening, constructs of the health belief model (perceived susceptibility to dementia, perceived severity of dementia, perceived benefits of screening, perceived barriers to screening), dementia worry, behavioral intentions and demographic factors were measured. A path analysis showed that the behavioral intention to undergo screening (path coefficient = 0.29) directly predicted participation in screening for cognitive impairment, whereas other psychological and demographic factors did not directly predict participation. The behavioral intention was explained by the perceived benefits of screening (path coefficient = 0.51), perceived barriers to screening (path coefficient = -0.19) and perceived susceptibility to dementia (path coefficient = 0.16). Participation in screening for cognitive impairment was positively predicted by higher behavioral intention to undergo screening. In turn, this behavioral intention was mainly predicted by the perceived benefits of screening among older adults. These findings suggest that emphasizing the perceived benefits and encouraging behavioral intentions might promote participation in screening for cognitive impairment. Geriatr Gerontol Int 2017; 17: 1197-1204. © 2016 Japan Geriatrics Society.

Symptoms of depression and anxiety as predictors of physical functioning in breast cancer patients. A prospective study using path analysis.

PubMed

Faller, Hermann; Strahl, André; Richard, Matthias; Niehues, Christiane; Meng, Karin

2017-12-01

Although symptoms of depression and anxiety are linked to health-related quality of life (HRQoL), the nature of this relationship remained unclear. We therefore aimed to examine, in a prospective study, both possible directions of impact in this relationship. To avoid conceptual and measurement overlap between depressive and anxiety symptoms, on the one hand, and HRQoL, on the other hand, we focused on the physical functioning component of HRQoL. We conducted a secondary analysis of a prospective cohort study with 436 female breast cancer patients (mean age 51 years). Both at baseline and after 12 months, we measured symptoms of depression and anxiety with the four-item Patient Heath Questionnaire (PHQ-4) and physical functioning with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30). Using path analysis, we estimated (1) the predictive value of symptoms of depression/anxiety for subsequent physical functioning and (2) the predictive value of physical functioning for subsequent symptoms of depression/anxiety, in the same model. Baseline symptoms of depression/anxiety predicted 1-year levels of physical functioning (depression: standardized β =  -.09, p = .024; anxiety: standardized β =  -.10, p = .009), while the reciprocal paths linking baseline physical functioning to subsequent depressive and anxiety symptoms were not significant, adjusting for the baseline scores of all outcome variables. Depressive and anxiety symptoms were predictors of the physical functioning component of HRQoL. Thus, if this relation is causal, treating breast cancer patients' depressive and anxiety symptoms may have a favorable impact on their self-reported physical functioning.

Path Analysis Association between Domestic Violence, Anxiety, Depression and Perceived Stress in Mothers and Children's Development.

PubMed

Vameghi, Roshanak; Amir Ali Akbari, Sedigheh; Sajedi, Firoozeh; Sajjadi, Homeira; Alavi Majd, Hamid

2016-01-01

Given that several factors involved in the incidence or exacerbation of developmental disorders in children, the present study aimed to investigate the relationship between some of the risk factors affecting mothers' health and development in children using path analysis. The present cross-sectional analytical study was conducted on 750 mothers and their children in health centers in Tehran, Iran in 2014 enrolled through multi-stage random sampling. Data were collected using a demographic and personal information questionnaire, the Perceived Stress Scale, Beck's depression Inventory, Spielberger' anxiety inventory, the WHO domestic violence questionnaire and an ages & stages questionnaire for assessing children's development. Data were analyzed using SPSS.19 (Chicago, IL, USA) and Lisrel 8.8. Developmental delay was observed in 12.1% of the children. The mean stress score was 23.94±8.62 in the mothers, 50.7% of whom showed mild to severe depression, 84.2% moderate to severe anxiety and 35.3% had been subjected to domestic violence. The path analysis showed that children's development was affected directly by perceived stress (β=-0.09) and depression (β=-0.17) and indirectly by domestic violence (β=-0.05278) and anxiety (β=-0.0357). Of all the variables examined, depression had the biggest influence on development in the children (β=-0.17). The proposed model showed a good fit (GFI=1, RMSEA=0.034). Children's development was influenced indirectly by domestic violence and anxiety and directly by perceived stress and depression in mothers. It is thus suggested that more concern and attention be paid to women's mental health and the domestic violence they experience.

A review of the application of nonattenuating frequency radars for estimating rain attenuation and space-diversity performance

NASA Technical Reports Server (NTRS)

Goldhirsh, J.

1979-01-01

Cumulative rain fade statistics are used by space communications engineers to establish transmitter power and receiver sensitivities for systems operating under various geometries, climates, and radio frequencies. Space-diversity performance criteria are also of interest. This work represents a review, in which are examined the many elements involved in the employment of single nonattenuating frequency radars for arriving at the desired information. The elements examined include radar techniques and requirements, phenomenological assumptions, path attenuation formulations and procedures, as well as error budgeting and calibration analysis. Included are the pertinent results of previous investigators who have used radar for rain-attenuation modeling. Suggestions are made for improving present methods.

Intergenerational communication satisfaction and age boundaries: comparative middle eastern data.

PubMed

Giles, Howard; Khajavy, Gholam Hassan; Choi, Charles W

2012-12-01

Guided by the communicative predicative model of aging, American and Iranian young adults' perceptions of communication with their peers, middle-aged and elderly adults were examined; subjective boundaries for these age categories were also explored. As age of target increased, so did attributions of benevolence, norms of politeness and deference, and communicative respect and avoidance; conversely, attributions of personal vitality and communication satisfaction decreased linearly. Path analysis was also adopted to examine the simultaneous relationships between the variables under study, and ultimately with cultural caveats largely supported, a hypothesized model was derived. The data were discussed in terms of their yielding refinements and elaborations to the communicative predicament and enhancement models of aging.

Time-Domain Pure-state Polarization Analysis of Surface Waves Traversing California

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

Zhang, J; Walter, W R; Lay, T

A time-domain pure-state polarization analysis method is used to characterize surface waves traversing California parallel to the plate boundary. The method is applied to data recorded at four broadband stations in California from twenty-six large, shallow earthquakes which occurred since 1988, yielding polarization parameters such as the ellipticity, Euler angles, instantaneous periods, and wave incident azimuths. The earthquakes are located along the circum-Pacific margin and the ray paths cluster into two groups, with great-circle paths connecting stations MHC and PAS or CMB and GSC. The first path (MHC-PAS) is in the vicinity of the San Andreas Fault System (SAFS), andmore » the second (CMB-GSC) traverses the Sierra Nevada Batholith parallel to and east of the SAFS. Both Rayleigh and Love wave data show refractions due to lateral velocity heterogeneities under the path, indicating that accurate phase velocity and attenuation analysis requires array measurements. The Rayleigh waves are strongly affected by low velocity anomalies beneath Central California, with ray paths bending eastward as waves travel toward the south, while Love waves are less affected, providing observables to constrain the depth extent of the anomalies. Strong lateral gradients in the lithospheric structure between the continent and the ocean are the likely cause of the path deflections.« less

The use of multiobjective calibration and regional sensitivity analysis in simulating hyporheic exchange

USGS Publications Warehouse

Naranjo, Ramon C.; Niswonger, Richard G.; Stone, Mark; Davis, Clinton; McKay, Alan

2012-01-01

We describe an approach for calibrating a two-dimensional (2-D) flow model of hyporheic exchange using observations of temperature and pressure to estimate hydraulic and thermal properties. A longitudinal 2-D heat and flow model was constructed for a riffle-pool sequence to simulate flow paths and flux rates for variable discharge conditions. A uniform random sampling approach was used to examine the solution space and identify optimal values at local and regional scales. We used a regional sensitivity analysis to examine the effects of parameter correlation and nonuniqueness commonly encountered in multidimensional modeling. The results from this study demonstrate the ability to estimate hydraulic and thermal parameters using measurements of temperature and pressure to simulate exchange and flow paths. Examination of the local parameter space provides the potential for refinement of zones that are used to represent sediment heterogeneity within the model. The results indicate vertical hydraulic conductivity was not identifiable solely using pressure observations; however, a distinct minimum was identified using temperature observations. The measured temperature and pressure and estimated vertical hydraulic conductivity values indicate the presence of a discontinuous low-permeability deposit that limits the vertical penetration of seepage beneath the riffle, whereas there is a much greater exchange where the low-permeability deposit is absent. Using both temperature and pressure to constrain the parameter estimation process provides the lowest overall root-mean-square error as compared to using solely temperature or pressure observations. This study demonstrates the benefits of combining continuous temperature and pressure for simulating hyporheic exchange and flow in a riffle-pool sequence. Copyright 2012 by the American Geophysical Union.

New Insights into Signed Path Coefficient Granger Causality Analysis.

PubMed

Zhang, Jian; Li, Chong; Jiang, Tianzi

2016-01-01

Granger causality analysis, as a time series analysis technique derived from econometrics, has been applied in an ever-increasing number of publications in the field of neuroscience, including fMRI, EEG/MEG, and fNIRS. The present study mainly focuses on the validity of "signed path coefficient Granger causality," a Granger-causality-derived analysis method that has been adopted by many fMRI researches in the last few years. This method generally estimates the causality effect among the time series by an order-1 autoregression, and defines a positive or negative coefficient as an "excitatory" or "inhibitory" influence. In the current work we conducted a series of computations from resting-state fMRI data and simulation experiments to illustrate the signed path coefficient method was flawed and untenable, due to the fact that the autoregressive coefficients were not always consistent with the real causal relationships and this would inevitablely lead to erroneous conclusions. Overall our findings suggested that the applicability of this kind of causality analysis was rather limited, hence researchers should be more cautious in applying the signed path coefficient Granger causality to fMRI data to avoid misinterpretation.

Alcohol Sensitivity Moderates the Indirect Associations between Impulsive Traits, Impaired Control over Drinking, and Drinking Outcomes

PubMed Central

Wardell, Jeffrey D.; Quilty, Lena C.; Hendershot, Christian S.

2017-01-01

Objective To examine impaired control over drinking behavior as a mediator of unique pathways from impulsive traits to alcohol outcomes in young adults and to investigate the moderating influence of self-reported sensitivity to alcohol on these pathways. Method Young adult heavy drinkers (N=172; n=82 women) recruited from the community completed self-report measures of impulsive traits (positive urgency, negative urgency, sensation seeking), alcohol sensitivity (Self-Rating of the Effects of Alcohol scale), impaired control over drinking, and alcohol use and problems. Multiple-groups path analysis was used to analyze the data. Results Path coefficients between urgency and impaired control were larger for individuals with lower versus higher self-reported sensitivity to alcohol. The same was true for the association between impaired control and alcohol problems. For participants lower on alcohol sensitivity, significant indirect paths were observed from both positive and negative urgency to all alcohol outcomes (quantity, frequency, and problems) mediated via impaired control. For participants higher on alcohol sensitivity, only the paths from negative urgency (but not positive urgency) to the three alcohol outcomes via impaired control were statistically significant. Sensation seeking was not uniquely associated with impaired control. Conclusions The findings indicate that relatively low sensitivity to the pharmacological effects of alcohol may exacerbate the association of urgency – especially positive urgency – with impaired control, supporting the notion that personality and level of response to alcohol may interact to increase risk for impaired control over drinking. PMID:25785803

Path planning in uncertain flow fields using ensemble method

NASA Astrophysics Data System (ADS)

Wang, Tong; Le Maître, Olivier P.; Hoteit, Ibrahim; Knio, Omar M.

2016-10-01

An ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.

Open-path FTIR data reduction algorithm with atmospheric absorption corrections: the NONLIN code

NASA Astrophysics Data System (ADS)

Phillips, William; Russwurm, George M.

1999-02-01

This paper describes the progress made to date in developing, testing, and refining a data reduction computer code, NONLIN, that alleviates many of the difficulties experienced in the analysis of open path FTIR data. Among the problems that currently effect FTIR open path data quality are: the inability to obtain a true I degree or background, spectral interferences of atmospheric gases such as water vapor and carbon dioxide, and matching the spectral resolution and shift of the reference spectra to a particular field instrument. This algorithm is based on a non-linear fitting scheme and is therefore not constrained by many of the assumptions required for the application of linear methods such as classical least squares (CLS). As a result, a more realistic mathematical model of the spectral absorption measurement process can be employed in the curve fitting process. Applications of the algorithm have proven successful in circumventing open path data reduction problems. However, recent studies, by one of the authors, of the temperature and pressure effects on atmospheric absorption indicate there exist temperature and water partial pressure effects that should be incorporated into the NONLIN algorithm for accurate quantification of gas concentrations. This paper investigates the sources of these phenomena. As a result of this study a partial pressure correction has been employed in NONLIN computer code. Two typical field spectra are examined to determine what effect the partial pressure correction has on gas quantification.

DiversePathsJ: diverse shortest paths for bioimage analysis.

PubMed

Uhlmann, Virginie; Haubold, Carsten; Hamprecht, Fred A; Unser, Michael

2018-02-01

We introduce a formulation for the general task of finding diverse shortest paths between two end-points. Our approach is not linked to a specific biological problem and can be applied to a large variety of images thanks to its generic implementation as a user-friendly ImageJ/Fiji plugin. It relies on the introduction of additional layers in a Viterbi path graph, which requires slight modifications to the standard Viterbi algorithm rules. This layered graph construction allows for the specification of various constraints imposing diversity between solutions. The software allows obtaining a collection of diverse shortest paths under some user-defined constraints through a convenient and user-friendly interface. It can be used alone or be integrated into larger image analysis pipelines. http://bigwww.epfl.ch/algorithms/diversepathsj. michael.unser@epfl.ch or fred.hamprecht@iwr.uni-heidelberg.de. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

Efficient computation paths for the systematic analysis of sensitivities

NASA Astrophysics Data System (ADS)

Greppi, Paolo; Arato, Elisabetta

2013-01-01

A systematic sensitivity analysis requires computing the model on all points of a multi-dimensional grid covering the domain of interest, defined by the ranges of variability of the inputs. The issues to efficiently perform such analyses on algebraic models are handling solution failures within and close to the feasible region and minimizing the total iteration count. Scanning the domain in the obvious order is sub-optimal in terms of total iterations and is likely to cause many solution failures. The problem of choosing a better order can be translated geometrically into finding Hamiltonian paths on certain grid graphs. This work proposes two paths, one based on a mixed-radix Gray code and the other, a quasi-spiral path, produced by a novel heuristic algorithm. Some simple, easy-to-visualize examples are presented, followed by performance results for the quasi-spiral algorithm and the practical application of the different paths in a process simulation tool.

The effects of differentiation of self, adult attachment, and sexual communication on sexual and marital satisfaction: a path analysis.

PubMed

Timm, Tina M; Keiley, Margaret K

2011-01-01

This article explores the relations among differentiation of self, adult attachment, sexual communication, sexual satisfaction, and marital satisfaction, in a path analysis model. In a sample of 205 married adults, the path analysis results indicated that (a) differentiation of self had no direct effect on marital or sexual satisfaction, although it was significantly related to sexual communication; (b) adult attachment had a direct effect on marital satisfaction, but not on sexual satisfaction; (c) sexual communication is a mediating variable; (d) sexual communication was positively related to sexual satisfaction and marital satisfaction; and (e) no gender differences existed in the model.

Descent graphs in pedigree analysis: applications to haplotyping, location scores, and marker-sharing statistics.

PubMed Central

Sobel, E.; Lange, K.

1996-01-01

The introduction of stochastic methods in pedigree analysis has enabled geneticists to tackle computations intractable by standard deterministic methods. Until now these stochastic techniques have worked by running a Markov chain on the set of genetic descent states of a pedigree. Each descent state specifies the paths of gene flow in the pedigree and the founder alleles dropped down each path. The current paper follows up on a suggestion by Elizabeth Thompson that genetic descent graphs offer a more appropriate space for executing a Markov chain. A descent graph specifies the paths of gene flow but not the particular founder alleles traveling down the paths. This paper explores algorithms for implementing Thompson's suggestion for codominant markers in the context of automatic haplotyping, estimating location scores, and computing gene-clustering statistics for robust linkage analysis. Realistic numerical examples demonstrate the feasibility of the algorithms. PMID:8651310

A Path Analysis of Latino Parental, Teenager and Cultural Variables in Teenagers' Sexual Attitudes, Norms, Self-Efficacy, and Sexual Intentions1

PubMed Central

Gaioso, Vanessa Pirani; Villarruel, Antonia Maria; Wilson, Lynda Anne; Azuero, Andres; Childs, Gwendolyn Denice; Davies, Susan Lane

2015-01-01

OBJECTIVE: to test a theoretical model based on the Parent-Based Expansion of the Theory of Planned Behavior examining relation between selected parental, teenager and cultural variables and Latino teenagers' intentions to engage in sexual behavior. METHOD: a cross-sectional correlational design based on a secondary data analysis of 130 Latino parent and teenager dyads. RESULTS: regression and path analysis procedures were used to test seven hypotheses and the results demonstrated partial support for the model. Parent familism and knowledge about sex were significantly associated with parents' attitudes toward sexual communication with their teenagers. Parent Latino acculturation was negatively associated with parents' self-efficacy toward sexual communication with their teenagers and positevely associated with parents' subjective norms toward sexual communication with their teenagers. Teenager knowledge about sex was significantly associated with higher levels of teenagers' attitudes and subjective norms about sexual communication with parents. Only the predictor of teenagers' attitudes toward having sex in the next 3 months was significantly associated with teenagers' intentions to have sex in the next 3 months. CONCLUSION: the results of this study provide important information to guide future research that can inform development of interventions to prevent risky teenager sexual behavior among Latinos. PMID:26312635

Analysis of Mexico City urban air pollution using nitrogen dioxide column density measurements from UV/Visible spectroscopy

NASA Astrophysics Data System (ADS)

Garcia Payne, D. G.; Grutter, M.; Melamed, M. L.

2010-12-01

The differential optical absorption spectroscopy method (DOAS) was used to get column densities of nitrogen dioxide (NO2) from the analysis of zenith sky UV/visible spectra. Since the optical path length provides critical information in interpreting NO2 column densities, in conjunction with NO2 column densities, the oxygen dimer (O4) column density was retrieved to give insight into the optical path length. We report observations of year round NO2 and O4 column densities (from august 2009 to september 2010) from which the mean seasonal levels and the daily evolution, as well as the occurrence of elevated pollution episodes are examined. Surface nitric oxide (NO) and NO2 from the local monitoring network, as well as wind data and the vertical aerosol density from continuous Lidar measurements are used in the analysis to investigate specific events in the context of local emissions from vehicular traffic, photochemical production and transport from industrial emissions. The NO2 column density measurements will enhance the understanding Mexico City urban air pollution. Recent research has begun to unravel the complexity of the air pollution problem in Mexico City and its effects not only locally but on a regional and global scale as well.

Emergency department crowding in Singapore: Insights from a systems thinking approach.

PubMed

Schoenenberger, Lukas K; Bayer, Steffen; Ansah, John P; Matchar, David B; Mohanavalli, Rajagopal L; Lam, Sean Sw; Ong, Marcus Eh

2016-01-01

Emergency Department crowding is a serious and international health care problem that seems to be resistant to most well intended but often reductionist policy approaches. In this study, we examine Emergency Department crowding in Singapore from a systems thinking perspective using causal loop diagramming to visualize the systemic structure underlying this complex phenomenon. Furthermore, we evaluate the relative impact of three different policies in reducing Emergency Department crowding in Singapore: introduction of geriatric emergency medicine, expansion of emergency medicine training, and implementation of enhanced primary care. The construction of the qualitative causal loop diagram is based on consultations with Emergency Department experts, direct observation, and a thorough literature review. For the purpose of policy analysis, a novel approach, the path analysis, is applied. The path analysis revealed that both the introduction of geriatric emergency medicine and the expansion of emergency medicine training may be associated with undesirable consequences contributing to Emergency Department crowding. In contrast, enhancing primary care was found to be germane in reducing Emergency Department crowding; in addition, it has apparently no negative side effects, considering the boundary of the model created. Causal loop diagramming was a powerful tool for eliciting the systemic structure of Emergency Department crowding in Singapore. Additionally, the developed model was valuable in testing different policy options.

Exploring the temporal structure of heterochronous sequences using TempEst (formerly Path-O-Gen).

PubMed

Rambaut, Andrew; Lam, Tommy T; Max Carvalho, Luiz; Pybus, Oliver G

2016-01-01

Gene sequences sampled at different points in time can be used to infer molecular phylogenies on a natural timescale of months or years, provided that the sequences in question undergo measurable amounts of evolutionary change between sampling times. Data sets with this property are termed heterochronous and have become increasingly common in several fields of biology, most notably the molecular epidemiology of rapidly evolving viruses. Here we introduce the cross-platform software tool, TempEst (formerly known as Path-O-Gen), for the visualization and analysis of temporally sampled sequence data. Given a molecular phylogeny and the dates of sampling for each sequence, TempEst uses an interactive regression approach to explore the association between genetic divergence through time and sampling dates. TempEst can be used to (1) assess whether there is sufficient temporal signal in the data to proceed with phylogenetic molecular clock analysis, and (2) identify sequences whose genetic divergence and sampling date are incongruent. Examination of the latter can help identify data quality problems, including errors in data annotation, sample contamination, sequence recombination, or alignment error. We recommend that all users of the molecular clock models implemented in BEAST first check their data using TempEst prior to analysis.

Contribution of biopsychosocial risk factors to nonspecific neck pain in office workers: A path analysis model.

PubMed

Paksaichol, Arpalak; Lawsirirat, Chaipat; Janwantanakul, Prawit

2015-01-01

The etiology of nonspecific neck pain is widely accepted to be multifactorial. Each risk factor has not only direct effects on neck pain but may also exert effects indirectly through other risk factors. This study aimed to test this hypothesized model in office workers. A one-year prospective cohort study of 559 healthy office workers was conducted. At baseline, a self-administered questionnaire and standardized physical examination were employed to gather biopsychosocial data. Follow-up data were collected every month for the incidence of neck pain. A regression model was built to analyze factors predicting the onset of neck pain. Path analysis was performed to examine direct and indirect associations between identified risk factors and neck pain. The onset of neck pain was predicted by female gender, having a history of neck pain, monitor position not being level with the eyes, and frequently perceived muscular tension, of which perceived muscular tension was the strongest effector on the onset of neck pain. Gender, history of neck pain, and monitor height had indirect effects on neck pain that were mediated through perceived muscular tension. History of neck pain was the most influential effector on perceived muscular tension. The results of this study support the hypothesis that each risk factors may contribute to the development of neck pain both directly and indirectly. The combination of risk factors necessary to cause neck pain is likely occupation specific. Perceived muscular tension is hypothesized to be an early sign of musculoskeletal symptoms.

Fear of cultural extinction and psychopathology among Mandaean refugees: an exploratory path analysis.

PubMed

Nickerson, Angela; Bryant, Richard A; Brooks, Robert; Steel, Zachary; Silove, Derrick

2009-01-01

The Mandaeans are a small religious community originating from Iraq and Iran who are facing the possibility of cultural extinction within the next few generations. This study aimed to examine the relationships between life experiences, psychopathology and fear of cultural extinction in Mandaean refugees. A survey was conducted of 315 adult Iraqi Mandaean refugees living in Australia. Past traumatic experiences and current resettlement difficulties were assessed. Mental health outcomes were also examined, including measures of posttraumatic stress disorder (PTSD) and depression. Fear of cultural extinction was measured by items developed in consultation with the Mandaean community. A path analysis was employed to investigate the relationship between trauma, living difficulties, PTSD, depression, and fear of cultural extinction. Results indicated that trauma and living difficulties impacted indirectly on fear of cultural extinction, while PTSD (and not depression) directly predicted levels of anxiety about the Mandaean culture ceasing to exist. The current findings indicate that past trauma and symptoms of posttraumatic stress contribute to fear of cultural extinction. Exposure to human rights violations enacted on the basis of religion has significant mental health consequences that extend beyond PTSD. The relationship between perception of threat, PTSD, and fear of cultural extinction is considered in the context of cognitive models of traumatic stress. Government immigration policy must prioritize the reunification of small, endangered groups to sustain cultural traditions. Treatment interventions implemented with cultural groups facing extinction should take into consideration anxiety about loss of culture.

Meaning of life, representation of death, and their association with psychological distress.

PubMed

Testoni, Ines; Sansonetto, Giulia; Ronconi, Lucia; Rodelli, Maddalena; Baracco, Gloria; Grassi, Luigi

2017-08-09

This paper presents a two-phase cross-sectional study aimed at examining the possible mitigating role of perceived meaning of life and representation of death on psychological distress, anxiety, and depression. The first phase involved 219 healthy participants, while the second encompassed 30 cancer patients. Each participant completed the Personal Meaning Profile (PMP), the Testoni Death Representation Scale (TDRS), the Hospital Anxiety and Depression Scale (HADS), and the Distress Thermometer (DT). The primary analyses comprised (1) correlation analyses between the overall scores of each of the instruments and (2) path analysis to assess the indirect effect of the PMP on DT score through anxiety and depression as determined by the HADS. The path analysis showed that the PMP was inversely correlated with depression and anxiety, which, in turn, mediated the effect on distress. Inverse correlations were found between several dimensions of the PMP, the DT, and the HADS-Anxiety and HADS-Depression subscales, in both healthy participants and cancer patients. Religious orientation (faith in God) was related to a stronger sense of meaning in life and the ontological representation of death as a passage, rather than annihilation. Our findings support the hypothesis that participants who represent death as a passage and have a strong perception of the meaning of life tend to report lower levels of distress, anxiety, and depression. We recommend that perceived meaning of life and representation of death be more specifically examined in the cancer and palliative care settings.

Rearfoot eversion has indirect effects on plantar fascia tension by changing the amount of arch collapse.

PubMed

Lee, Sae Yong; Hertel, Jay; Lee, Sung Cheol

2010-01-01

Rearfoot eversion motion and arch height are believed to contribute to increased tension on the plantar fascia and arch collapse during gait but the specifics of these relationships are not clear. To examine the relationships among static arch height, rearfoot eversion, dynamic arch height, and plantar fascia tension. 28 healthy males participated. After static arch height was measured, the subjects were asked to run at 4.5m/s while frontal plane rearfoot motion, dynamic arch height, and ground reaction forces were collected. The relationships among variables were examined with bivariate correlations and path analysis. The results indicated a high correlation between dynamic arch height and static arch height (r=0.642), plantar fascia tension (r=-0.797), and maximum rearfoot eversion motion during gait (r=-0.518). The path analysis model without the direct rearfoot eversion effect explained 81.2% of the variance in plantar fascia tension, while the model with the direct rearfoot eversion effect explained 82.1% of the variance in plantar fascia tension. Including the indirect effect of maximum rearfoot eversion motion on plantar fascia tension through control of dynamic arch height is the model that best explains the interrelationships of these foot characteristics. The amount of maximum rearfoot eversion motion itself is not a good predictor of plantar fascia tension, however, together with the arch height, maximum rearfoot eversion motion is a good predictor because it has a pronounced indirect effect on plantar fascia tension. Copyright 2010. Published by Elsevier Ltd.

Unique effects and moderators of effects of sources on self-efficacy: A model-based meta-analysis.

PubMed

Byars-Winston, Angela; Diestelmann, Jacob; Savoy, Julia N; Hoyt, William T

2017-11-01

Self-efficacy beliefs are strong predictors of academic pursuits, performance, and persistence, and in theory are developed and maintained by 4 classes of experiences Bandura (1986) referred to as sources: performance accomplishments (PA), vicarious learning (VL), social persuasion (SP), and affective arousal (AA). The effects of sources on self-efficacy vary by performance domain and individual difference factors. In this meta-analysis (k = 61 studies of academic self-efficacy; N = 8,965), we employed B. J. Becker's (2009) model-based approach to examine cumulative effects of the sources as a set and unique effects of each source, controlling for the others. Following Becker's recommendations, we used available data to create a correlation matrix for the 4 sources and self-efficacy, then used these meta-analytically derived correlations to test our path model. We further examined moderation of these associations by subject area (STEM vs. non-STEM), grade, sex, and ethnicity. PA showed by far the strongest unique association with self-efficacy beliefs. Subject area was a significant moderator, with sources collectively predicting self-efficacy more strongly in non-STEM (k = 14) compared with STEM (k = 47) subjects (R2 = .37 and .22, respectively). Within studies of STEM subjects, grade level was a significant moderator of the coefficients in our path model, as were 2 continuous study characteristics (percent non-White and percent female). Practical implications of the findings and future research directions are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

[Not Available].

PubMed

Yanashima, Ryoji; Kitagawa, Noriyuki; Matsubara, Yoshiya; Weatheritt, Robert; Oka, Kotaro; Kikuchi, Shinichi; Tomita, Masaru; Ishizaki, Shun

2009-01-01

The scale-free and small-world network models reflect the functional units of networks. However, when we investigated the network properties of a signaling pathway using these models, no significant differences were found between the original undirected graphs and the graphs in which inactive proteins were eliminated from the gene expression data. We analyzed signaling networks by focusing on those pathways that best reflected cellular function. Therefore, our analysis of pathways started from the ligands and progressed to transcription factors and cytoskeletal proteins. We employed the Python module to assess the target network. This involved comparing the original and restricted signaling cascades as a directed graph using microarray gene expression profiles of late onset Alzheimer's disease. The most commonly used method of shortest-path analysis neglects to consider the influences of alternative pathways that can affect the activation of transcription factors or cytoskeletal proteins. We therefore introduced included k-shortest paths and k-cycles in our network analysis using the Python modules, which allowed us to attain a reasonable computational time and identify k-shortest paths. This technique reflected results found in vivo and identified pathways not found when shortest path or degree analysis was applied. Our module enabled us to comprehensively analyse the characteristics of biomolecular networks and also enabled analysis of the effects of diseases considering the feedback loop and feedforward loop control structures as an alternative path.

Cyber Contingency Analysis version 1.x

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

Contingency analysis based approach for quantifying and examining the resiliency of a cyber system in respect to confidentiality, integrity and availability. A graph representing an organization's cyber system and related resources is used for the availability contingency analysis. The mission critical paths associated with an organization are used to determine the consequences of a potential contingency. A node (or combination of nodes) are removed from the graph to analyze a particular contingency. The value of all mission critical paths that are disrupted by that contingency are used to quantify its severity. A total severity score can be calculated based onmore » the complete list of all these contingencies. A simple n1 analysis can be done in which only one node is removed at a time for the analysis. We can also compute nk analysis, where k is the number of nodes to simultaneously remove for analysis. A contingency risk score can also be computed, which takes the probability of the contingencies into account. In addition to availability, we can also quantify confidentiality and integrity scores for the system. These treat user accounts as potential contingencies. The amount (and type) of files that an account can read to is used to compute the confidentiality score. The amount (and type) of files that an account can write to is used to compute the integrity score. As with availability analysis, we can use this information to compute total severity scores in regards to confidentiality and integrity. We can also take probability into account to compute associated risk scores.« less

Theoretical analysis for scaling law of thermal blooming based on optical phase deference

NASA Astrophysics Data System (ADS)

Sun, Yunqiang; Huang, Zhilong; Ren, Zebin; Chen, Zhiqiang; Guo, Longde; Xi, Fengjie

2016-10-01

In order to explore the laser propagation influence of thermal blooming effect of pipe flow and to analysis the influencing factors, scaling law theoretical analysis of the thermal blooming effects in pipe flow are carry out in detail based on the optical path difference caused by thermal blooming effects in pipe flow. Firstly, by solving the energy coupling equation of laser beam propagation, the temperature of the flow is obtained, and then the optical path difference caused by the thermal blooming is deduced. Through the analysis of the influence of pipe size, flow field and laser parameters on the optical path difference, energy scaling parameters Ne=nTαLPR2/(ρɛCpπR02) and geometric scaling parameters Nc=νR2/(ɛL) of thermal blooming for the pipe flow are derived. Secondly, for the direct solution method, the energy coupled equations have analytic solutions only for the straight tube with Gauss beam. Considering the limitation of directly solving the coupled equations, the dimensionless analysis method is adopted, the analysis is also based on the change of optical path difference, same scaling parameters for the pipe flow thermal blooming are derived, which makes energy scaling parameters Ne and geometric scaling parameters Nc have good universality. The research results indicate that when the laser power and the laser beam diameter are changed, thermal blooming effects of the pipeline axial flow caused by optical path difference will not change, as long as you keep energy scaling parameters constant. When diameter or length of the pipe changes, just keep the geometric scaling parameters constant, the pipeline axial flow gas thermal blooming effects caused by optical path difference distribution will not change. That is to say, when the pipe size and laser parameters change, if keeping two scaling parameters with constant, the pipeline axial flow thermal blooming effects caused by the optical path difference will not change. Therefore, the energy scaling parameters and the geometric scaling parameters can really describe the gas thermal blooming effect in the axial pipe flow. These conclusions can give a good reference for the construction of the thermal blooming test system of laser system. Contrasted with the thermal blooming scaling parameters of the Bradley-Hermann distortion number ND and Fresnel number NF, which were derived based on the change of far field beam intensity distortion, the scaling parameters of pipe flow thermal blooming deduced from the optical path deference variation are very suitable for the optical system with short laser propagation distance, large Fresnel number and obviously changed optical path deference.

Parental influences on children's self-regulation of energy intake: Insights from developmental literature on emotion regulation

USDA-ARS?s Scientific Manuscript database

This article examines the role of parents in the development of children's self-regulation of energy intake. Various paths of parental influence are offered based on the literature on parental influences on children's emotion self-regulation. The parental paths include modeling, responses to childre...

Younger and Older Adults' "Good-Enough" Interpretations of Garden-Path Sentences

ERIC Educational Resources Information Center

Christianson, Kiel; Williams, Carrick C.; Zacks, Rose T.; Ferreira, Fernanda

2006-01-01

We report 3 experiments that examined younger and older adults' reliance on "good-enough" interpretations for garden-path sentences (e.g., "While Anna dressed the baby played in the crib") as indicated by their responding "Yes" to questions probing the initial, syntactically unlicensed interpretation (e.g., "Did Anna dress the baby?"). The…

Experiential Learning: A New Research Path to the Study of Journalism Education.

ERIC Educational Resources Information Center

Brandon, Wanda

2002-01-01

Examines the learning environment of journalism education. Considers historical perspectives of journalism education before laying the groundwork for a new research area. Suggests that the experiential learning approach offers a way of assessing the quality of learning and of breaking new paths into the study of journalism education. (SG)

The Learning and Decision-Making Patterns of Traditional and Non-Traditional Superintendents on Long Island, New York

ERIC Educational Resources Information Center

Finn, Christine

2015-01-01

The purpose of this research was to examine the accomplishments and obstacles of central office administrators who have followed traditional educational career paths with those who have followed non-traditional paths. The demographic markers, educational backgrounds, administrative responsibilities and tasks, and significant positive and negative…

Highways and Byways: The Career Paths of Senior Student Affairs Officers

ERIC Educational Resources Information Center

Tull, Ashley; Miller, Michael T.

2009-01-01

The highways and byways, or career paths, to the Senior Student Affairs Officer (SSAO) position differ based on a variety of variables. This study examined several variables including the induction or graduate preparation process, professional pathways, and professional and academic involvement of more than half of current land grant SSAOs. Data…

Adolescent Support Seeking as a Path to Adult Functional Independence

ERIC Educational Resources Information Center

Szwedo, David E.; Hessel, Elenda T.; Loeb, Emily L.; Hafen, Christopher A.; Allen, Joseph P.

2017-01-01

The potential importance of depending on others during adolescence to establish independence in young adulthood was examined across adolescence to emerging adulthood. Participants included 184 teens (46% male; 42% non-White), their mothers, best friends, and romantic partners, assessed at ages 13-14, 18, 21-22, and 25. Path analyses showed that…

Motivations and Paths to Becoming Faculty at Minority Serving Institutions

ERIC Educational Resources Information Center

Blake, Daniel

2018-01-01

Drawing upon 15 qualitative interviews with early- to mid-career faculty (seven men and eight women) at Minority Serving Institutions (MSIs), this study examines the diverse motivations and paths those faculty members have taken to becoming professors at their respective institutions. The faculty come from a range of MSIs (Historically Black…

Modeling Cultural Context for Aspiring Women Educational Leaders

ERIC Educational Resources Information Center

Sperandio, Jill

2010-01-01

Purpose: The purpose of the paper is to discuss and examine the development of frameworks and models to guide future research into studies of women's paths to educational leadership worldwide. Design/methodology/approach: A grounded theory approach to the development of a model of the factors and their interaction that determine the path to…

A Path Model of Expressive Vocabulary Skills in Initially Preverbal Preschool Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

McDaniel, Jena; Yoder, Paul; Watson, Linda R.

2017-01-01

We examined direct and indirect paths involving receptive vocabulary and diversity of key consonants used in communication (DKCC) to improve understanding of why previously identified value-added predictors are associated with later expressive vocabulary for initially preverbal children with autism spectrum disorder (ASD; n = 87). Intentional…

An Analysis of the Role of ATC in the AILS Concept

NASA Technical Reports Server (NTRS)

Waller, Marvin C.; Doyle, Thomas M.; McGee, Frank G.

2000-01-01

Airborne information for lateral spacing (AILS) is a concept for making approaches to closely spaced parallel runways in instrument meteorological conditions (IMC). Under the concept, each equipped aircraft will assume responsibility for accurately managing its flight path along the approach course and maintaining separation from aircraft on the parallel approach. This document presents the results of an analysis of the AILS concept from an Air Traffic Control (ATC) perspective. The process has been examined in a step by step manner to determine ATC system support necessary to safely conduct closely spaced parallel approaches using the AILS concept. The analysis resulted in recognizing a number of issues related to integrating the process into the airspace system and proposes operating procedures.

TabPath: interactive tables for metabolic pathway analysis.

PubMed

Moraes, Lauro Ângelo Gonçalves de; Felestrino, Érica Barbosa; Assis, Renata de Almeida Barbosa; Matos, Diogo; Lima, Joubert de Castro; Lima, Leandro de Araújo; Almeida, Nalvo Franco; Setubal, João Carlos; Garcia, Camila Carrião Machado; Moreira, Leandro Marcio

2018-03-15

Information about metabolic pathways in a comparative context is one of the most powerful tool to help the understanding of genome-based differences in phenotypes among organisms. Although several platforms exist that provide a wealth of information on metabolic pathways of diverse organisms, the comparison among organisms using metabolic pathways is still a difficult task. We present TabPath (Tables for Metabolic Pathway), a web-based tool to facilitate comparison of metabolic pathways in genomes based on KEGG. From a selection of pathways and genomes of interest on the menu, TabPath generates user-friendly tables that facilitate analysis of variations in metabolism among the selected organisms. TabPath is available at http://200.239.132.160:8686. lmmorei@gmail.com.

Path Analysis Tests of Theoretical Models of Children's Memory Performance

ERIC Educational Resources Information Center

DeMarie, Darlene; Miller, Patricia H.; Ferron, John; Cunningham, Walter R.

2004-01-01

Path analysis was used to test theoretical models of relations among variables known to predict differences in children's memory--strategies, capacity, and metamemory. Children in kindergarten to fourth grade (chronological ages 5 to 11) performed different memory tasks. Several strategies (i.e., sorting, clustering, rehearsal, and self-testing)…

Public health financial management competencies.

PubMed

Honoré, Peggy A; Costich, Julia F

2009-01-01

The absence of appropriate financial management competencies has impeded progress in advancing the field of public health finance. It also inhibits the ability to professionalize this sector of the workforce. Financial managers should play a critical role by providing information relevant to decision making. The lack of fundamental financial management knowledge and skills is a barrier to fulfilling this role. A national expert committee was convened to examine this issue. The committee reviewed standards related to financial and business management practices within public health and closely related areas. Alignments were made with national standards such as those established for government chief financial officers. On the basis of this analysis, a comprehensive set of public health financial management competencies was identified and examined further by a review panel. At a minimum, the competencies can be used to define job descriptions, assess job performance, identify critical gaps in financial analysis, create career paths, and design educational programs.

Compressive Failure of Fiber Composites under Multi-Axial Loading

NASA Technical Reports Server (NTRS)

Basu, Shiladitya; Waas, Anthony M.; Ambur, Damodar R.

2006-01-01

This paper examines the compressive strength of a fiber reinforced lamina under multi-axial stress states. An equilibrium analysis is carried out in which a kinked band of rotated fibers, described by two angles, is sandwiched between two regions in which the fibers are nominally straight. Proportional multi-axial stress states are examined. The analysis includes the possibility of bifurcation from the current equilibrium state. The compressive strength of the lamina is contingent upon either attaining a load maximum in the equilibrium response or satisfaction of a bifurcation condition, whichever occurs first. The results show that for uniaxial loading a non-zero kink band angle beta produces the minimum limit load. For multi-axial loading, different proportional loading paths show regimes of bifurcation dominated and limit load dominated behavior. The present results are able to capture the beneficial effect of transverse compression in raising the composite compressive strength as observed in experiments.

Adolescent Risk: The Co-Occurrence of Illness, Suicidality, and Substance Use

ERIC Educational Resources Information Center

Husler, Gebhard; Blakeney, Ronny; Werlen, Egon

2005-01-01

Illness is rarely considered a "risk factor" in adolescence. This study tests illness, suicidality and substance use as outcome measures in a path analysis of 1028 Swiss adolescents in secondary prevention programs. The model showed that negative mood (depression and anxiety) predicted two paths. One path led from negative mood to…

Nonadiabatic quantum path analysis of high-order harmonic generation: Role of the carrier-envelope phase on short and long paths

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

Sansone, G.; Stagira, S.; Nisoli, M.

2004-07-01

High-order harmonic generation process in the few- and multiple-optical-cycle regime is theoretically investigated, using the saddle-point method generalized to account for nonadiabatic effects. The influence of the carrier-envelope phase of the driving pulses on the various electron quantum paths is analyzed. We demonstrate that the short and long quantum paths are influenced in different ways by the carrier-envelope phase. In particular, we show that clear phase effects are visible on the long quantum paths even in the multiple-optical-cycle regime, while the short quantum paths are significantly influenced by the carrier-envelope phase only in the few-optical-cycle regime.

Comparison of Kalman filter estimates of zenith atmospheric path delays using the global positioning system and very long baseline interferometry

NASA Technical Reports Server (NTRS)

Tralli, David M.; Lichten, Stephen M.; Herring, Thomas A.

1992-01-01

Kalman filter estimates of zenith nondispersive atmospheric path delays at Westford, Massachusetts, Fort Davis, Texas, and Mojave, California, were obtained from independent analyses of data collected during January and February 1988 using the GPS and VLBI. The apparent accuracy of the path delays is inferred by examining the estimates and covariances from both sets of data. The ability of the geodetic data to resolve zenith path delay fluctuations is determined by comparing further the GPS Kalman filter estimates with corresponding wet path delays derived from water vapor radiometric data available at Mojave over two 8-hour data spans within the comparison period. GPS and VLBI zenith path delay estimates agree well within one standard deviation formal uncertainties (from 10-20 mm for GPS and 3-15 mm for VLBI) in four out of the five possible comparisons, with maximum differences of 5 and 21 mm over 8- to 12-hour data spans.

Quality of service routing in wireless ad hoc networks

NASA Astrophysics Data System (ADS)

Sane, Sachin J.; Patcha, Animesh; Mishra, Amitabh

2003-08-01

An efficient routing protocol is essential to guarantee application level quality of service running on wireless ad hoc networks. In this paper we propose a novel routing algorithm that computes a path between a source and a destination by considering several important constraints such as path-life, availability of sufficient energy as well as buffer space in each of the nodes on the path between the source and destination. The algorithm chooses the best path from among the multiples paths that it computes between two endpoints. We consider the use of control packets that run at a priority higher than the data packets in determining the multiple paths. The paper also examines the impact of different schedulers such as weighted fair queuing, and weighted random early detection among others in preserving the QoS level guarantees. Our extensive simulation results indicate that the algorithm improves the overall lifetime of a network, reduces the number of dropped packets, and decreases the end-to-end delay for real-time voice application.

Visually based path-planning by Japanese monkeys.

PubMed

Mushiake, H; Saito, N; Sakamoto, K; Sato, Y; Tanji, J

2001-03-01

To construct an animal model of strategy formation, we designed a maze path-finding task. First, we asked monkeys to capture a goal in the maze by moving a cursor on the screen. Cursor movement was linked to movements of each wrist. When the animals learned the association between cursor movement and wrist movement, we established a start and a goal in the maze, and asked them to find a path between them. We found that the animals took the shortest pathway, rather than approaching the goal randomly. We further found that the animals adopted a strategy of selecting a fixed intermediate point in the visually presented maze to select one of the shortest pathways, suggesting a visually based path planning. To examine their capacity to use that strategy flexibly, we transformed the task by blocking pathways in the maze, providing a problem to solve. The animals then developed a strategy of solving the problem by planning a novel shortest path from the start to the goal and rerouting the path to bypass the obstacle.

Parental Influences on Children's Self-Regulation of Energy Intake: Insights from Developmental Literature on Emotion Regulation

PubMed Central

Frankel, Leslie A.; Hughes, Sheryl O.; O'Connor, Teresia M.; Power, Thomas G.; Fisher, Jennifer O.; Hazen, Nancy L.

2012-01-01

The following article examines the role of parents in the development of children's self-regulation of energy intake. Various paths of parental influence are offered based on the literature on parental influences on children's emotion self-regulation. The parental paths include modeling, responses to children's behavior, assistance in helping children self-regulate, and motivating children through rewards and punishments. Additionally, sources of variation in parental influences on regulation are examined, including parenting style, child temperament, and child-parent attachment security. Parallels in the nature of parents' role in socializing children's regulation of emotions and energy intake are examined. Implications for future research are discussed. PMID:22545206

Multiple paths in complex tasks

NASA Technical Reports Server (NTRS)

Galanter, Eugene; Wiegand, Thomas; Mark, Gloria

1987-01-01

The relationship between utility judgments of subtask paths and the utility of the task as a whole was examined. The convergent validation procedure is based on the assumption that measurements of the same quantity done with different methods should covary. The utility measures of the subtasks were obtained during the performance of an aircraft flight controller navigation task. Analyses helped decide among various models of subtask utility combination, whether the utility ratings of subtask paths predict the whole tasks utility rating, and indirectly, whether judgmental models need to include the equivalent of cognitive noise.

Analytical modeling of the structureborne noise path on a small twin-engine aircraft

NASA Technical Reports Server (NTRS)

Cole, J. E., III; Stokes, A. Westagard; Garrelick, J. M.; Martini, K. F.

1988-01-01

The structureborne noise path of a six passenger twin-engine aircraft is analyzed. Models of the wing and fuselage structures as well as the interior acoustic space of the cabin are developed and used to evaluate sensitivity to structural and acoustic parameters. Different modeling approaches are used to examine aspects of the structureborne path. These approaches are guided by a number of considerations including the geometry of the structures, the frequency range of interest, and the tractability of the computations. Results of these approaches are compared with experimental data.

Planning minimum-energy paths in an off-road environment with anisotropic traversal costs and motion constraints. Doctoral thesis

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

Ross, R.S.

1989-06-01

For a vehicle operating across arbitrarily-contoured terrain, finding the most fuel-efficient route between two points can be viewed as a high-level global path-planning problem with traversal costs and stability dependent on the direction of travel (anisotropic). The problem assumes a two-dimensional polygonal map of homogeneous cost regions for terrain representation constructed from elevation information. The anisotropic energy cost of vehicle motion has a non-braking component dependent on horizontal distance, a braking component dependent on vertical distance, and a constant path-independent component. The behavior of minimum-energy paths is then proved to be restricted to a small, but optimal set of traversalmore » types. An optimal-path-planning algorithm, using a heuristic search technique, reduces the infinite number of paths between the start and goal points to a finite number by generating sequences of goal-feasible window lists from analyzing the polygonal map and applying pruning criteria. The pruning criteria consist of visibility analysis, heading analysis, and region-boundary constraints. Each goal-feasible window lists specifies an associated convex optimization problem, and the best of all locally-optimal paths through the goal-feasible window lists is the globally-optimal path. These ideas have been implemented in a computer program, with results showing considerably better performance than the exponential average-case behavior predicted.« less

Quantifying Cell Fate Decisions for Differentiation and Reprogramming of a Human Stem Cell Network: Landscape and Biological Paths

PubMed Central

Li, Chunhe; Wang, Jin

2013-01-01

Cellular reprogramming has been recently intensively studied experimentally. We developed a global potential landscape and kinetic path framework to explore a human stem cell developmental network composed of 52 genes. We uncovered the underlying landscape for the stem cell network with two basins of attractions representing stem and differentiated cell states, quantified and exhibited the high dimensional biological paths for the differentiation and reprogramming process, connecting the stem cell state and differentiated cell state. Both the landscape and non-equilibrium curl flux determine the dynamics of cell differentiation jointly. Flux leads the kinetic paths to be deviated from the steepest descent gradient path, and the corresponding differentiation and reprogramming paths are irreversible. Quantification of paths allows us to find out how the differentiation and reprogramming occur and which important states they go through. We show the developmental process proceeds as moving from the stem cell basin of attraction to the differentiation basin of attraction. The landscape topography characterized by the barrier heights and transition rates quantitatively determine the global stability and kinetic speed of cell fate decision process for development. Through the global sensitivity analysis, we provided some specific predictions for the effects of key genes and regulation connections on the cellular differentiation or reprogramming process. Key links from sensitivity analysis and biological paths can be used to guide the differentiation designs or reprogramming tactics. PMID:23935477

Analysis of Non-Uniform Gain for Control of a Deformable Mirror in an Adaptive-Optics System

DTIC Science & Technology

2008-03-01

Turbulence Estimator SM Path SH WFS – DM Path Figure 3.6: Primary layout. The blue boxed components is representative of the SM path, the red boxed components...layout that was developed for the majority of the experiments conducted. 3.1.5.1 Steering Mirror Path. This path, boxed in blue in Figure 3.6, is used to...Christou, T.S. Duncan, R.J. Eager, M.A. Ealey, B.L. Ellerbroek, R.Q. Fugate , G.W. Jones, R.M. Kuhns, D.J. Lee, W.H. Lowrey, M.D. Oliker, R.E. Ruane

Vulnerabilities, Influences and Interaction Paths: Failure Data for Integrated System Risk Analysis

NASA Technical Reports Server (NTRS)

Malin, Jane T.; Fleming, Land

2006-01-01

We describe graph-based analysis methods for identifying and analyzing cross-subsystem interaction risks from subsystem connectivity information. By discovering external and remote influences that would be otherwise unexpected, these methods can support better communication among subsystem designers at points of potential conflict and to support design of more dependable and diagnosable systems. These methods identify hazard causes that can impact vulnerable functions or entities if propagated across interaction paths from the hazard source to the vulnerable target. The analysis can also assess combined impacts of And-Or trees of disabling influences. The analysis can use ratings of hazards and vulnerabilities to calculate cumulative measures of the severity and importance. Identification of cross-subsystem hazard-vulnerability pairs and propagation paths across subsystems will increase coverage of hazard and risk analysis and can indicate risk control and protection strategies.

Multi-scale comparison of source parameter estimation using empirical Green's function approach

NASA Astrophysics Data System (ADS)

Chen, X.; Cheng, Y.

2015-12-01

Analysis of earthquake source parameters requires correction of path effect, site response, and instrument responses. Empirical Green's function (EGF) method is one of the most effective methods in removing path effects and station responses by taking the spectral ratio between a larger and smaller event. Traditional EGF method requires identifying suitable event pairs, and analyze each event individually. This allows high quality estimations for strictly selected events, however, the quantity of resolvable source parameters is limited, which challenges the interpretation of spatial-temporal coherency. On the other hand, methods that exploit the redundancy of event-station pairs are proposed, which utilize the stacking technique to obtain systematic source parameter estimations for a large quantity of events at the same time. This allows us to examine large quantity of events systematically, facilitating analysis of spatial-temporal patterns, and scaling relationship. However, it is unclear how much resolution is scarified during this process. In addition to the empirical Green's function calculation, choice of model parameters and fitting methods also lead to biases. Here, using two regional focused arrays, the OBS array in the Mendocino region, and the borehole array in the Salton Sea geothermal field, I compare the results from the large scale stacking analysis, small-scale cluster analysis, and single event-pair analysis with different fitting methods to systematically compare the results within completely different tectonic environment, in order to quantify the consistency and inconsistency in source parameter estimations, and the associated problems.

Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia.

PubMed

Langen, Carolyn D; White, Tonya; Ikram, M Arfan; Vernooij, Meike W; Niessen, Wiro J

2015-01-01

Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significantly different connections comparing multiple metrics are presented. On the global level, "bi-modal comparison plots" show the distribution of uni- and bi-modal group differences and the relationship between structure and function. Differences between brain lobes are visualized using "worm plots". Group differences in connections are examined with an existing visualization, the "connectogram". These visualizations were evaluated in two proof-of-concept studies: (1) middle-aged versus elderly subjects; and (2) patients with schizophrenia versus controls. Each included two measures derived from diffusion weighted images and two from functional magnetic resonance images. The structural measures were minimum cost path between two anatomical regions according to the "Statistical Analysis of Minimum cost path based Structural Connectivity" method and the average fractional anisotropy along the fiber. The functional measures were Pearson's correlation and partial correlation of mean regional time series. The relationship between structure and function was similar in both studies. Uni-modal group differences varied greatly between connectivity types. Group differences were identified in both studies globally, within brain lobes and between regions. In the aging study, minimum cost path was highly effective in identifying group differences on all levels; fractional anisotropy and mean correlation showed smaller differences on the brain lobe and regional levels. In the schizophrenia study, minimum cost path and fractional anisotropy showed differences on the global level and within brain lobes; mean correlation showed small differences on the lobe level. Only fractional anisotropy and mean correlation showed regional differences. The presented visualizations were helpful in comparing and evaluating connectivity measures on multiple levels in both studies.

Influence of social cognitive and ethnic variables on academic goals of underrepresented students in science and engineering: a multiple-groups analysis.

PubMed

Byars-Winston, Angela; Estrada, Yannine; Howard, Christina; Davis, Dalelia; Zalapa, Juan

2010-04-01

This study investigated the academic interests and goals of 223 African American, Latino/a, Southeast Asian, and Native American undergraduate students in two groups: biological science and engineering (S/E) majors. Using social cognitive career theory (Lent, Brown, & Hackett, 1994), we examined the relationships of social cognitive variables (math/science academic self-efficacy, math/science outcome expectations), along with the influence of ethnic variables (ethnic identity, other-group orientation) and perceptions of campus climate to their math/science interests and goal commitment to earn an S/E degree. Path analysis revealed that the hypothesized model provided good overall fit to the data, revealing significant relationships from outcome expectations to interests and to goals. Paths from academic self-efficacy to S/E goals and from interests to S/E goals varied for students in engineering and biological science. For both groups, other-group orientation was positively related to self-efficacy and support was found for an efficacy-mediated relationship between perceived campus climate and goals. Theoretical and practical implications of the study's findings are considered as well as future research directions.

Influence of Social Cognitive and Ethnic Variables on Academic Goals of Underrepresented Students in Science and Engineering: A Multiple-Groups Analysis

PubMed Central

Byars-Winston, Angela; Estrada, Yannine; Howard, Christina; Davis, Dalelia; Zalapa, Juan

2010-01-01

This study investigated the academic interests and goals of 223 African American, Latino/a, Southeast Asian, and Native American undergraduate students in two groups: biological science and engineering (S/E) majors. Using social cognitive career theory (Lent, Brown, & Hackett, 1994), we examined the relationships of social cognitive variables (math/science academic self-efficacy, math/science outcome expectations), along with the influence of ethnic variables (ethnic identity, other-group orientation) and perceptions of campus climate to their math/science interests and goal commitment to earn an S/E degree. Path analysis revealed that the hypothesized model provided good overall fit to the data, revealing significant relationships from outcome expectations to interests and to goals. Paths from academic self-efficacy to S/E goals and from interests to S/E goals varied for students in engineering and biological science. For both groups, other-group orientation was positively related to self-efficacy and support was found for an efficacy-mediated relationship between perceived campus climate and goals. Theoretical and practical implications of the study’s findings are considered as well as future research directions. PMID:20495610

The influence of leadership practices and empowerment on Canadian nurse manager outcomes.

PubMed

Spence Laschinger, Heather K; Wong, Carol A; Grau, Ashley L; Read, Emily A; Pineau Stam, Lisa M

2012-10-01

To examine the influence of senior nurse leadership practices on middle and first-line nurse managers' experiences of empowerment and organizational support and ultimately on their perceptions of patient care quality and turnover intentions. Empowering leadership has played an important role in staff nurse retention but there is limited research to explain the mechanisms by which leadership influences nurse managers' turnover intentions. This study was a secondary analysis of data collected using non-experimental, predictive mailed survey design. Data from 231 middle and 788 first-line Canadian acute care managers was used to test the hypothesized model using path analysis in each group. The results showed an adequate fit of the hypothesized model in both groups but with an added path between leadership practices and support in the middle line group. Transformational leadership practices of senior nurses empower middle- and first-line nurse managers, leading to increased perceptions of organizational support, quality care and decreased intent to leave. Empowered nurse managers at all levels who feel supported by their organizations are more likely to stay in their roles, remain committed to achieving quality patient care and act as influential role models for potential future leaders. © 2011 Blackwell Publishing Ltd.

Fractionating dead reckoning: role of the compass, odometer, logbook, and home base establishment in spatial orientation

NASA Astrophysics Data System (ADS)

Wallace, Douglas G.; Martin, Megan M.; Winter, Shawn S.

2008-06-01

Rats use multiple sources of information to maintain spatial orientation. Although previous work has focused on rats’ use of environmental cues, a growing number of studies have demonstrated that rats also use self-movement cues to organize navigation. This review examines the extent that kinematic analysis of naturally occurring behavior has provided insight into processes that mediate dead-reckoning-based navigation. This work supports a role for separate systems in processing self-movement cues that converge on the hippocampus. The compass system is involved in deriving directional information from self-movement cues; whereas, the odometer system is involved in deriving distance information from self-movement cues. The hippocampus functions similar to a logbook in that outward path unique information from the compass and odometer is used to derive the direction and distance of a path to the point at which movement was initiated. Finally, home base establishment may function to reset this system after each excursion and anchor environmental cues to self-movement cues. The combination of natural behaviors and kinematic analysis has proven to be a robust paradigm to investigate the neural basis of spatial orientation.

Fractionating dead reckoning: role of the compass, odometer, logbook, and home base establishment in spatial orientation

PubMed Central

Martin, Megan M.; Winter, Shawn S.

2008-01-01

Rats use multiple sources of information to maintain spatial orientation. Although previous work has focused on rats' use of environmental cues, a growing number of studies have demonstrated that rats also use self-movement cues to organize navigation. This review examines the extent that kinematic analysis of naturally occurring behavior has provided insight into processes that mediate dead-reckoning-based navigation. This work supports a role for separate systems in processing self-movement cues that converge on the hippocampus. The compass system is involved in deriving directional information from self-movement cues; whereas, the odometer system is involved in deriving distance information from self-movement cues. The hippocampus functions similar to a logbook in that outward path unique information from the compass and odometer is used to derive the direction and distance of a path to the point at which movement was initiated. Finally, home base establishment may function to reset this system after each excursion and anchor environmental cues to self-movement cues. The combination of natural behaviors and kinematic analysis has proven to be a robust paradigm to investigate the neural basis of spatial orientation. PMID:18553065

Teacher Preference, Peer Rejection, and Student Aggression: A Prospective Study of Transactional Influence and Independent Contributions to Emotional Adjustment and Grades

PubMed Central

Mercer, Sterett H.

2008-01-01

This study assessed the importance of teacher preference of individual students, relative to peer rejection and student aggression, as an independent predictor of children's emotional adjustment and grades. First, a longitudinal, cross-lagged path analysis was conducted to determine the patterns of influence among teacher preference, peer rejection, and student aggression. Then, parallel growth analyses were examined to test whether lower initial and declining teacher preference, beyond the influence of initial-level and change in peer rejection and student aggression, predicted change in loneliness, depression, social anxiety, and grades. Social adjustment, emotional adjustment, and academic adjustment were assessed in the fall and spring of two consecutive school years with 1,193 third-grade students via peer-, teacher-, and self-report instruments as well as school records. In the cross-lagged path analysis, reciprocal influence over time between teacher preference and peer rejection was found, and student aggression predicted lower teacher preference and higher peer rejection. In the growth analyses, initial and declining teacher preference were independent predictors of increasing loneliness and declining grades. Discussion focuses on the relevance of the results within a transactional model of school adaptation. PMID:19083378

Teacher preference, peer rejection, and student aggression: a prospective study of transactional influence and independent contributions to emotional adjustment and grades.

PubMed

Mercer, Sterett H; DeRosier, Melissa E

2008-12-01

This study assessed the importance of teacher preference of individual students, relative to peer rejection and student aggression, as an independent predictor of children's emotional adjustment and grades. First, a longitudinal, cross-lagged path analysis was conducted to determine the patterns of influence among teacher preference, peer rejection, and student aggression. Then, parallel growth analyses were examined to test whether lower initial and declining teacher preference, beyond the influence of initial level and change in peer rejection and student aggression, predicted change in loneliness, depression, social anxiety, and grades. Social adjustment, emotional adjustment, and academic adjustment were assessed in the fall and spring of two consecutive school years with 1193 third-grade students via peer-, teacher-, and self-report instruments as well as school records. In the cross-lagged path analysis, reciprocal influence over time between teacher preference and peer rejection was found, and student aggression predicted lower teacher preference and higher peer rejection. In the growth analyses, initial and declining teacher preference were independent predictors of increasing loneliness and declining grades. Discussion focuses on the relevance of the results within a transactional model of school adaptation.

On the nonlinear forced response of the North Atlantic atmosphere to meridional shifts of the Gulf Stream path

NASA Astrophysics Data System (ADS)

Seo, H.; Kwon, Y. O.; Joyce, T. M.; Ummenhofer, C.

2016-12-01

This study examines the North Atlantic atmospheric circulation response to the meridional shift of Gulf Stream path using a large-ensemble, high-resolution, and hemispheric-scale WRF simulations. The model is forced with wintertime SST anomalies derived from a wide range of Gulf Stream shift scenarios. The key result of the model experiments, supported in part by an independent analysis of a reanalysis data set, is that the large-scale, quasi-steady North Atlantic circulation response is unambiguously nonlinear about the sign and amplitude of chosen SST anomalies. This nonlinear response prevails over the weak linear response and resembles the negative North Atlantic Oscillation, the leading intrinsic mode of variability in the model and the observations. Further analysis of the associated dynamics reveals that the nonlinear responses are accompanied by the anomalous southward shift of the North Atlantic eddy-driven jet stream, which is reinforced nearly equally by the high-frequency transient eddy feedback and the low-frequency high-latitude wave breaking events. The result highlights the importance of the intrinsically nonlinear transient eddy dynamics and eddy-mean flow interactions in generating the nonlinear forced response to the meridional shift in the Gulf Stream.

Micro-CT evaluation of several glide path techniques and ProTaper Next shaping outcomes in maxillary first molar curved canals.

PubMed

Alovisi, M; Cemenasco, A; Mancini, L; Paolino, D; Scotti, N; Bianchi, C C; Pasqualini, D

2017-04-01

To evaluate the ability of ProGlider instruments, PathFiles and K-files to maintain canal anatomy during glide path preparation using X-ray computed micro-tomography (micro-CT). Forty-five extracted maxillary first permanent molars were selected. Mesio-buccal canals were randomly assigned (n = 15) to manual K-file, PathFile or ProGlider groups for glide path preparation. Irrigation was achieved with 5% NaOCl and 10% EDTA. After glide path preparation, each canal was shaped with ProTaper Next X1 and X2 to working length. Specimens were scanned (isotropic voxel size 9.1 μm) for matching volumes and surface areas and post-treatment analyses. Canal volume, surface area, centroid shift, canal geometry variation through ratio of diameter ratios and ratio of cross-sectional areas were assessed in the apical and coronal levels and at the point of maximum canal curvature. One-way factorial anovas were used to evaluate the significance of instrument in the various canal regions. Post-glide path analysis revealed that instrument factor was significant at the apical level for both the ratio of diameter ratios and the ratio of cross-sectional areas (P < 0.001), with an improved maintenance of root canal geometry by ProGlider and PathFile. At the coronal level and point of maximum canal curvature, ProGlider demonstrated a tendency to pre-flare the root canal compared with K-file and PathFile. PathFile and ProGlider demonstrated a significantly lower centroid shift compared with K-file at the apical level (P = 0.023). Post-shaping analysis demonstrated a more centred preparation of ProGlider, compared with PathFile and K-files, with no significant differences for other parameters. Use of ProGlider instruments led to less canal transportation than PathFiles and K-files. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Working conditions, socioeconomic factors and low birth weight: path analysis.

PubMed

Mahmoodi, Zohreh; Karimlou, Masoud; Sajjadi, Homeira; Dejman, Masoumeh; Vameghi, Meroe; Dolatian, Mahrokh

2013-09-01

In recent years, with socioeconomic changes in the society, the presence of women in the workplace is inevitable. The differences in working condition, especially for pregnant women, has adverse consequences like low birth weight. This study was conducted with the aim to model the relationship between working conditions, socioeconomic factors, and birth weight. This study was conducted in case-control design. The control group consisted of 500 women with normal weight babies, and the case group, 250 women with low weight babies from selected hospitals in Tehran. Data were collected using a researcher-made questionnaire to determine mothers' lifestyle during pregnancy with low birth weight with health-affecting social determinants approach. This questionnaire investigated women's occupational lifestyle in terms of working conditions, activities, and job satisfaction. Data were analyzed with SPSS-16 and Lisrel-8.8 software using statistical path analysis. The final path model fitted well (CFI =1, RMSEA=0.00) and showed that among direct paths, working condition (β=-0.032), among indirect paths, household income (β=-0.42), and in the overall effect, unemployed spouse (β=-0.1828) had the most effects on the low birth weight. Negative coefficients indicate decreasing effect on birth weight. Based on the path analysis model, working condition and socioeconomic status directly and indirectly influence birth weight. Thus, as well as attention to treatment and health care (biological aspect), special attention must also be paid to mothers' socioeconomic factors.

The Digital Reading Path: Researching Modes and Multidirectionality with iPads

ERIC Educational Resources Information Center

Simpson, Alyson; Walsh, Maureen; Rowsell, Jennifer

2013-01-01

This paper reports a study that examines the integration of tablet technologies such as iPads into literacy lessons to investigate how reading and meaning-making occur within this digital medium. Specifically in this paper, we discuss the concept of reading paths as applied to physical and cognitive planes of meaning-making. The paper reports on…

Negotiating the Landscape: The Path to Employment for Individuals with Disabilities in the TANF System.

ERIC Educational Resources Information Center

Timmons, Jaimie Ciulla; Foley, Susan; Whitney-Thomas, Jean; Green, Joseph; Casey, Judi

This report discusses the outcomes of a study that examined the impact of welfare reform on individuals with disabilities in Massachusetts and Wisconsin. New welfare reforms required individuals to develop marketable skills and acceptable work behaviors and move along a path to employment. For individuals with disabilities in the Temporary…

Paths to Bullying in Online Gaming: The Effects of Gender, Preference for Playing Violent Games, Hostility, and Aggressive Behavior on Bullying

ERIC Educational Resources Information Center

Yang, Shu Ching

2012-01-01

This study examined a sample of adolescent online game players and explored the relationships between their gender, preference for video games (VG), hostility, aggressive behavior, experiences of cyberbullying, and victimization. The path relationships among the variables were further validated with structure equation modeling. Among the…

Uncovering Paths to Teaching: Teacher Identity and the Cultural Arts of Memory

ERIC Educational Resources Information Center

Florio-Ruane, Susan; Williams, Linda G.

2008-01-01

This article reports the authors' collaborative research on teacher identity as revealed by examining paths to teaching. When individuals enter the teaching profession, they appear to be making a personal career choice. Beginning educators look ahead, envisioning the teachers they hope to become. At this time it is rare to look backward, to…

Nonstandard Career Paths and Profiles of Commitment to Life Roles: A Complex Relation

ERIC Educational Resources Information Center

Fournier, Genevieve; Lachance, Lise; Bujold, Charles

2009-01-01

The career paths (ascending, interesting, uninteresting, descending) of 124 White Canadian francophones (62 men, 62 women) who had experienced nonstandard and precarious work for the last three years were examined in relation to the participants' profiles of commitment to three life roles (work, family, and duality, that is, investment in both…

The "Body Pedagogics" of an Elite Footballer's Career Path--Analysing Zlatan Ibrahimovic's Biography

ERIC Educational Resources Information Center

Andersson, Joacim; Maivorsdotter, Ninitha

2017-01-01

Background: Pedagogical research on career is encouraged to not limit sport learning to athletic skills, coaching effectiveness and coach-athlete relationships, but to also focus on learning in a multidimensional sense in the context of an athlete's individual and social biography. This article examines an elite athlete's career path as a body…

Mentoring and Leadership: A Practical Application for One's Career Path

ERIC Educational Resources Information Center

Laughlin, Kevin; Moore, Holly

2012-01-01

This paper explores mentoring and mentorship at the beginning and ending of one's career path and the role of mentoring in the process. It frames the mentoring and leadership discussion using the lens of a first year teacher in a LaSallian elementary school in Browning, Montana, on the Blackfeet Indian Reservation. Topics examined in this paper…

WATER QUALITY CHANGES IN HYPORHEIC FLOW PATHS BETWEEN A LARGE GRAVEL BED RIVER AND OFF-CHANNEL ALCOVES IN OREGON, USA

EPA Science Inventory

Changes in water quality that occur as water flows along hyporheic flow paths may have important effects on surface water quality and aquatic habitat, yet very few studies have examined these hyporheic processes along large gravel bed rivers. To determine water quality changes as...

Universal Session-Level Change Processes in an Early Session of Psychotherapy: Path Models

ERIC Educational Resources Information Center

Kolden, Gregory G.; Chisholm-Stockard, Sarah M.; Strauman, Timothy J.; Tierney, Sandy C.; Mullen, Elizabeth A.; Schneider, Kristin L.

2006-01-01

The authors used structural equation modeling to investigate universal change processes identified in the generic model of psychotherapy (GMP). Three path models of increasing complexity were examined in Study 1 in dynamic therapy. The best fitting model from Study one was replicated in Study two for participants receiving either cognitive or…

Support at Work and Home: The Path to Satisfaction through Balance

ERIC Educational Resources Information Center

Ferguson, Merideth; Carlson, Dawn; Zivnuska, Suzanne; Whitten, Dwayne

2012-01-01

This study examines social support (from both coworkers and partners) and its path to satisfaction through work-family balance. This study fills a gap by explaining how support impacts satisfaction in the same domain, across domains, and how it crosses over to impact the partner's domain. Using a matched dataset of 270 job incumbents and their…

A study of snake-like locomotion through the analysis of a flexible robot model

PubMed Central

Cicconofri, Giancarlo; DeSimone, Antonio

2015-01-01

We examine the problem of snake-like locomotion by studying a system consisting of a planar inextensible elastic rod with adjustable spontaneous curvature, which provides an internal actuation mechanism that mimics muscular action in a snake. Using a Cosserat model, we derive the equations of motion in two special cases: one in which the rod can only move along a prescribed curve, and one in which the rod is constrained to slide longitudinally without slipping laterally, but the path is not fixed a priori (free-path case). The second setting is inspired by undulatory locomotion of snakes on flat surfaces. The presence of constraints leads in both cases to non-standard boundary conditions that allow us to close and solve the equations of motion. The kinematics and dynamics of the system can be recovered from a one-dimensional equation, without any restrictive assumption on the followed trajectory or the actuation. We derive explicit formulae highlighting the role of spontaneous curvature in providing the driving force (and the steering, in the free-path case) needed for locomotion. We also provide analytical solutions for a special class of serpentine motions, which enable us to discuss the connection between observed trajectories, internal actuation and forces exchanged with the environment. PMID:26807040

A novel multi-segment path analysis based on a heterogeneous velocity model for the localization of acoustic emission sources in complex propagation media.

PubMed

Gollob, Stephan; Kocur, Georg Karl; Schumacher, Thomas; Mhamdi, Lassaad; Vogel, Thomas

2017-02-01

In acoustic emission analysis, common source location algorithms assume, independently of the nature of the propagation medium, a straight (shortest) wave path between the source and the sensors. For heterogeneous media such as concrete, the wave travels in complex paths due to the interaction with the dissimilar material contents and with the possible geometrical and material irregularities present in these media. For instance, cracks and large air voids present in concrete influence significantly the way the wave travels, by causing wave path deviations. Neglecting these deviations by assuming straight paths can introduce significant errors to the source location results. In this paper, a novel source localization method called FastWay is proposed. It accounts, contrary to most available shortest path-based methods, for the different effects of material discontinuities (cracks and voids). FastWay, based on a heterogeneous velocity model, uses the fastest rather than the shortest travel paths between the source and each sensor. The method was evaluated both numerically and experimentally and the results from both evaluation tests show that, in general, FastWay was able to locate sources of acoustic emissions more accurately and reliably than the traditional source localization methods. Copyright © 2016 Elsevier B.V. All rights reserved.

Neighborhoods, Social Support, and African American Adolescents' Mental Health Outcomes: A Multilevel Path Analysis

ERIC Educational Resources Information Center

Hurd, Noelle M.; Stoddard, Sarah A.; Zimmerman, Marc A.

2013-01-01

This study explored how neighborhood characteristics may relate to African American adolescents' internalizing symptoms via adolescents' social support and perceptions of neighborhood cohesion. Participants included 571 urban, African American adolescents (52% female; "M" age = 17.8). A multilevel path analysis testing both direct and…

NASA TLA workload analysis support. Volume 1: Detailed task scenarios for general aviation and metering and spacing studies

NASA Technical Reports Server (NTRS)

Sundstrom, J. L.

1980-01-01

The techniques required to produce and validate six detailed task timeline scenarios for crew workload studies are described. Specific emphasis is given to: general aviation single pilot instrument flight rules operations in a high density traffic area; fixed path metering and spacing operations; and comparative workload operation between the forward and aft-flight decks of the NASA terminal control vehicle. The validation efforts also provide a cursory examination of the resultant demand workload based on the operating procedures depicted in the detailed task scenarios.

Child Sexual Abuse, Sexual Anxiety, and Sexual Satisfaction: The Role of Self-Capacities.

PubMed

Bigras, Noémie; Godbout, Natacha; Briere, John

2015-01-01

Research indicates that child sexual abuse produces lasting alterations in interpersonal relatedness, identity, and affect regulation, often referred to as self-capacity disturbance. Child sexual abuse also has been shown to negatively impact sexual functioning. This study examined the role of altered self-capacities in mediating the relationship between child sexual abuse and sexual responses. Path analysis revealed that child sexual abuse was related to sexual anxiety and decreased sexual satisfaction through its association with reduced self-awareness and a propensity to be involved in difficult interpersonal relationships.

An advanced terrain modeler for an autonomous planetary rover

NASA Technical Reports Server (NTRS)

Hunter, E. L.

1980-01-01

A roving vehicle capable of autonomously exploring the surface of an alien world is under development and an advanced terrain modeler to characterize the possible paths of the rover as hazardous or safe is presented. This advanced terrain modeler has several improvements over the Troiani modeler that include: a crosspath analysis, better determination of hazards on slopes, and methods for dealing with missing returns at the extremities of the sensor field. The results from a package of programs to simulate the roving vehicle are then examined and compared to results from the Troiani modeler.

The ABC (in any D) of logarithmic CFT

NASA Astrophysics Data System (ADS)

Hogervorst, Matthijs; Paulos, Miguel; Vichi, Alessandro

2017-10-01

Logarithmic conformal field theories have a vast range of applications, from critical percolation to systems with quenched disorder. In this paper we thoroughly examine the structure of these theories based on their symmetry properties. Our analysis is model-independent and holds for any spacetime dimension. Our results include a determination of the general form of correlation functions and conformal block decompositions, clearing the path for future bootstrap applications. Several examples are discussed in detail, including logarithmic generalized free fields, holographic models, self-avoiding random walks and critical percolation.

Sectioning Coated Specimens Without Edge Rounding

NASA Technical Reports Server (NTRS)

Mckechnie, Timothy N.

1988-01-01

New method devised for preparation of cross sections of coated specimens for scanning electron microscopy or energy-dispersive analysis without rounding edges of coatings. After cutting and polishing, specimen section remains smooth and flat so it can be examined under high magnification out to edge of coating. Sectioned blade first electroplated with hard nickel 0.003 in., then encapsulated in two layers of material: soft conductive material at bottom and 0.25 in. of hard diallyl phthalate at top. Nickel plate provides electrical path from surface of section to conductive material below.

Identification of limit cycles in multi-nonlinearity, multiple path systems

NASA Technical Reports Server (NTRS)

Mitchell, J. R.; Barron, O. L.

1979-01-01

A method of analysis which identifies limit cycles in autonomous systems with multiple nonlinearities and multiple forward paths is presented. The FORTRAN code for implementing the Harmonic Balance Algorithm is reported. The FORTRAN code is used to identify limit cycles in multiple path and nonlinearity systems while retaining the effects of several harmonic components.

Assessment of the Performance of a Dual-Frequency Surface Reference Technique

NASA Technical Reports Server (NTRS)

Meneghini, Robert; Liao, Liang; Tanelli, Simone; Durden, Stephen

2013-01-01

The high correlation of the rain-free surface cross sections at two frequencies implies that the estimate of differential path integrated attenuation (PIA) caused by precipitation along the radar beam can be obtained to a higher degree of accuracy than the path-attenuation at either frequency. We explore this finding first analytically and then by examining data from the JPL dual-frequency airborne radar using measurements from the TC4 experiment obtained during July-August 2007. Despite this improvement in the accuracy of the differential path attenuation, solving the constrained dual-wavelength radar equations for parameters of the particle size distribution requires not only this quantity but the single-wavelength path attenuation as well. We investigate a simple method of estimating the single-frequency path attenuation from the differential attenuation and compare this with the estimate derived directly from the surface return.

Overlap in the functional neural systems involved in semantic and episodic memory retrieval.

PubMed

Rajah, M N; McIntosh, A R

2005-03-01

Neuroimaging and neuropsychological data suggest that episodic and semantic memory may be mediated by distinct neural systems. However, an alternative perspective is that episodic and semantic memory represent different modes of processing within a single declarative memory system. To examine whether the multiple or the unitary system view better represents the data we conducted a network analysis using multivariate partial least squares (PLS ) activation analysis followed by covariance structural equation modeling (SEM) of positron emission tomography data obtained while healthy adults performed episodic and semantic verbal retrieval tasks. It is argued that if performance of episodic and semantic retrieval tasks are mediated by different memory systems, then there should differences in both regional activations and interregional correlations related to each type of retrieval task, respectively. The PLS results identified brain regions that were differentially active during episodic retrieval versus semantic retrieval. Regions that showed maximal differences in regional activity between episodic retrieval tasks were used to construct separate functional models for episodic and semantic retrieval. Omnibus tests of these functional models failed to find a significant difference across tasks for both functional models. The pattern of path coefficients for the episodic retrieval model were not different across tasks, nor were the path coefficients for the semantic retrieval model. The SEM results suggest that the same memory network/system was engaged across tasks, given the similarities in path coefficients. Therefore, activation differences between episodic and semantic retrieval may ref lect variation along a continuum of processing during task performance within the context of a single memory system.

New Insights into Signed Path Coefficient Granger Causality Analysis

PubMed Central

Zhang, Jian; Li, Chong; Jiang, Tianzi

2016-01-01

Granger causality analysis, as a time series analysis technique derived from econometrics, has been applied in an ever-increasing number of publications in the field of neuroscience, including fMRI, EEG/MEG, and fNIRS. The present study mainly focuses on the validity of “signed path coefficient Granger causality,” a Granger-causality-derived analysis method that has been adopted by many fMRI researches in the last few years. This method generally estimates the causality effect among the time series by an order-1 autoregression, and defines a positive or negative coefficient as an “excitatory” or “inhibitory” influence. In the current work we conducted a series of computations from resting-state fMRI data and simulation experiments to illustrate the signed path coefficient method was flawed and untenable, due to the fact that the autoregressive coefficients were not always consistent with the real causal relationships and this would inevitablely lead to erroneous conclusions. Overall our findings suggested that the applicability of this kind of causality analysis was rather limited, hence researchers should be more cautious in applying the signed path coefficient Granger causality to fMRI data to avoid misinterpretation. PMID:27833547

Using refraction in thick glass plates for optical path length modulation in low coherence interferometry.

PubMed

Kröger, Niklas; Schlobohm, Jochen; Pösch, Andreas; Reithmeier, Eduard

2017-09-01

In Michelson interferometer setups the standard way to generate different optical path lengths between a measurement arm and a reference arm relies on expensive high precision linear stages such as piezo actuators. We present an alternative approach based on the refraction of light at optical interfaces using a cheap stepper motor with high gearing ratio to control the rotation of a glass plate. The beam path is examined and a relation between angle of rotation and change in optical path length is devised. As verification, an experimental setup is presented, and reconstruction results from a measurement standard are shown. The reconstructed step height from this setup lies within 1.25% of the expected value.

Calibration of neural networks using genetic algorithms, with application to optimal path planning

NASA Technical Reports Server (NTRS)

Smith, Terence R.; Pitney, Gilbert A.; Greenwood, Daniel

1987-01-01

Genetic algorithms (GA) are used to search the synaptic weight space of artificial neural systems (ANS) for weight vectors that optimize some network performance function. GAs do not suffer from some of the architectural constraints involved with other techniques and it is straightforward to incorporate terms into the performance function concerning the metastructure of the ANS. Hence GAs offer a remarkably general approach to calibrating ANS. GAs are applied to the problem of calibrating an ANS that finds optimal paths over a given surface. This problem involves training an ANS on a relatively small set of paths and then examining whether the calibrated ANS is able to find good paths between arbitrary start and end points on the surface.

The effects of composition and thermal path on hot ductility of forging steels

NASA Astrophysics Data System (ADS)

Connolly, Brendan M.

This work examines the effects of composition and thermal path on the hot ductility of several forging steels with varied aluminum and nitrogen content. The primary mechanisms and controlling factors related to hot ductility are identified with a focus on the role of precipitates and segregation. The unique thermal paths and solidification structures of large cross-section forging ingots are discussed. Hot ductility testing is performed in a manner that approximates industrial conditions experienced by large cross-section forging ingots. A computer model for precipitation of aluminum nitride and vanadium nitride in austenite is presented. Industrial material is examined for comparison to experimental findings. It is found that increased aluminum and nitrogen content coarsens the as-solidified structure. The combined effects of microsegregation and uphill diffusion during deformation allow for carbide precipitation at prior austenite grain boundaries which reduces the hot ductility.

Predicting Deformation Limits of Dual-Phase Steels Under Complex Loading Paths

DOE PAGES

Cheng, G.; Choi, K. S.; Hu, X.; ...

2017-04-05

Here in this study, the deformation limits of various DP980 steels are examined with the deformation instability theory. Under uniaxial tension, overall stress–strain curves of the material are estimated based on a simple rule of mixture (ROM) with both iso-strain and iso-stress assumptions. Under complex loading paths, an actual microstructure-based finite element (FE) method is used to resolve the deformation compatibilities explicitly between the soft ferrite and hard martensite phases. The results show that, for uniaxial tension, the deformation instability theory with iso-strain-based ROM can be used to provide the lower bound estimate of the uniform elongation (UE) for themore » various DP980 considered. Under complex loading paths, the deformation instability theory with microstructure-based FE method can be used in examining the effects of various microstructural features on the deformation limits of DP980 steels.« less

Predicting Deformation Limits of Dual-Phase Steels Under Complex Loading Paths

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

Cheng, G.; Choi, K. S.; Hu, X.

The deformation limits of various DP980 steels are examined in this study with deformation instability theory. Under uniaxial tension, overall stress-strain curves of the material are estimated based on simple rule of mixture (ROM) with both iso-strain and iso-stress assumptions. Under complex loading paths, actual microstructure-based finite element (FE) method is used to explicitly resolve the deformation incompatibilities between the soft ferrite and hard martensite phases. The results show that, for uniaxial tension, the deformation instability theory with iso-strain-based ROM can be used to provide the lower bound estimate of the uniform elongation (UE) for the various DP980 considered. Undermore » complex loading paths, the deformation instability theory with microstructure-based FE method can be used in examining the effects of various microstructural features on the deformation limits of DP980 steels.« less

Predicting Deformation Limits of Dual-Phase Steels Under Complex Loading Paths

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

Cheng, G.; Choi, K. S.; Hu, X.

Here in this study, the deformation limits of various DP980 steels are examined with the deformation instability theory. Under uniaxial tension, overall stress–strain curves of the material are estimated based on a simple rule of mixture (ROM) with both iso-strain and iso-stress assumptions. Under complex loading paths, an actual microstructure-based finite element (FE) method is used to resolve the deformation compatibilities explicitly between the soft ferrite and hard martensite phases. The results show that, for uniaxial tension, the deformation instability theory with iso-strain-based ROM can be used to provide the lower bound estimate of the uniform elongation (UE) for themore » various DP980 considered. Under complex loading paths, the deformation instability theory with microstructure-based FE method can be used in examining the effects of various microstructural features on the deformation limits of DP980 steels.« less

Observed cloud reflectivities and liquid water paths: An update

NASA Technical Reports Server (NTRS)

Coakley, James A., Jr.; Snider, Jack B.

1990-01-01

The FIRE microwave radiometer observations of liquid water path from San Nicolas Island and simultaneous NOAA AVHRR observations of cloud reflectivity were used to test a relationship between cloud liquid water path and cloud reflectivity that is often used in general circulation climate models (Stephens, 1978). The results of attempts to improve the data analysis which was described at the previous FIRE Science Team Workshop and elsewhere (Coakley and Snider, 1989) are reported. The improvements included the analysis of additional satellite passes over San Nicolas and sensitivity studies to estimate the effects on the observed reflectivities due to: (1) nonzero surface reflectivities beneath the clouds; (2) the anisotropy of the reflected radiances observed by the AVHRR; (3) small scale spatial structure in the liquid water path; and (4) adjustments to the calibration of AVHRR.

Fault tree analysis: NiH2 aerospace cells for LEO mission

NASA Technical Reports Server (NTRS)

Klein, Glenn C.; Rash, Donald E., Jr.

1992-01-01

The Fault Tree Analysis (FTA) is one of several reliability analyses or assessments applied to battery cells to be utilized in typical Electric Power Subsystems for spacecraft in low Earth orbit missions. FTA is generally the process of reviewing and analytically examining a system or equipment in such a way as to emphasize the lower level fault occurrences which directly or indirectly contribute to the major fault or top level event. This qualitative FTA addresses the potential of occurrence for five specific top level events: hydrogen leakage through either discrete leakage paths or through pressure vessel rupture; and four distinct modes of performance degradation - high charge voltage, suppressed discharge voltage, loss of capacity, and high pressure.

Energy loss of fast quarks in nuclei.

PubMed

Johnson, M B; Kopeliovich, B Z; Potashnikova, I K; McGaughey, P L; Moss, J M; Peng, J C; Garvey, G T; Leitch, M J; Adams, M R; Alde, D M; Baer, H W; Barlett, M L; Brown, C N; Cooper, W E; Carey, T A; Danner, G; Hoffmann, G W; Hsiung, Y B; Kaplan, D M; Klein, A; Lee, C; Lillberg, J W; McCarthy, R L; Mishra, C S; Wang, M J

2001-05-14

We report an analysis of the nuclear dependence of the yield of Drell-Yan dimuons from the 800 GeV/c proton bombardment of 2H, C, Ca, Fe, and W targets. Employing a new formulation of the Drell-Yan process in the rest frame of the nucleus, this analysis examines the effect of initial-state energy loss and shadowing on the nuclear-dependence ratios versus the incident proton's momentum fraction and dimuon effective mass. The resulting energy loss per unit path length is -dE/dz = 2.32+/-0.52+/-0.5 GeV/fm. This is the first observation of a nonzero energy loss of partons traveling in a nuclear environment.

Critical discourse analysis of social justice in nursing's foundational documents.

PubMed

Valderama-Wallace, Claire P

2017-07-01

Social inequities threaten the health of the global population. A superficial acknowledgement of social justice by nursing's foundational documents may limit the degree to which nurses view injustice as relevant to nursing practice and education. The purpose was to examine conceptualizations of social justice and connections to broader contexts in the most recent editions. Critical discourse analysis examines and uncovers dynamics related to power, language, and inequality within the American Nurses Association's Code of Ethics, Scope and Standards of Practice, and Social Policy Statement. This analysis found ongoing inconsistencies in conceptualizations of social justice. Although the Code of Ethics integrates concepts related to social justice far more than the other two, tension between professionalism and social change emerges. The discourse of professionalism renders interrelated cultural, social, economic, historical, and political contexts nearly invisible. Greater consistency would provide a clearer path for nurses to mobilize and engage in the courageous work necessary to address social injustice. These findings also call for an examination of how nurses can critique and use the power and privilege of professionalism to amplify the connection between social institutions and health equity in nursing education, practice, and policy development. © 2017 Wiley Periodicals, Inc.

On the spatial relationship between lightning discharges and propagation paths of perturbed subionospheric VLF/LF signals

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

Wai-Yeung Yip; Inan, U.S.; Orville, R.E.

1991-01-01

A study has been made of the spatial relationship between propagation paths of subionospheric VLF/LF signals exhibiting sudden amplitude perturbations (Trimpi events) and time correlated cloud-to-ground lightning flashes. On each of the 4 days examined the storm centers were located close to the signal path from the NAU transmitter (28.5-kHz) in Puerto Rico to Stanford (SU) and were at large distances from the propagation path of the 48.5-kHz transmitter signal from Nebraska to SU. Nevertheless, no Trimpi events were observed on the former path, while many were seen on the latter. Furthermore, the detected Trimpi perturbations of the 48.5-kHz signalmore » received at Stanford were found to be associated with the lightning activity in the distant storm centers. Since the NAU-SU path lies entirely at L < 2 and the 48.5-SU path is located mostly at 2< L <3, the L dependent magnetospheric conditions which determine the level of lightning-induced electron precipitation are different along the two paths. Thus, the authors postulate that the observed difference in Trimpi occurence on the two paths was due to the different magnetospheric conditions. Hence the occurence of Trimpi events over the geographical region corresponding to L <3 may be more dominantly controlled by magnetospheric conditions than the source lightning distribution.« less

Leadership, Organizational Climate, and Perceived Burden of Evidence-Based Practice in Mental Health Services.

PubMed

Brimhall, Kim C; Fenwick, Karissa; Farahnak, Lauren R; Hurlburt, Michael S; Roesch, Scott C; Aarons, Gregory A

2016-09-01

The use of evidence-based practices (EBPs) is associated with favorable client outcomes, yet perceived burden of using EBPs may affect the adoption and implementation of such practices. Multilevel path analysis was used to examine the associations of transformational leadership with organizational climate, and their associations with perceived burden of using EBPs. Results indicated significant relationships between transformational leadership and empowering and demoralizing climates, and between demoralizing climate and perceived burden of EBPs. We found significant indirect associations of leadership and perceived burden through organizational climate. Findings suggest that further research is needed to examine the extent to which improving leadership and organizational climate may reduce perceived burden and use of EBPs with the ultimate goal of enhancing quality of care.

Spatial Updating Strategy Affects the Reference Frame in Path Integration.

PubMed

He, Qiliang; McNamara, Timothy P

2018-06-01

This study investigated how spatial updating strategies affected the selection of reference frames in path integration. Participants walked an outbound path consisting of three successive waypoints in a featureless environment and then pointed to the first waypoint. We manipulated the alignment of participants' final heading at the end of the outbound path with their initial heading to examine the adopted reference frame. We assumed that the initial heading defined the principal reference direction in an allocentric reference frame. In Experiment 1, participants were instructed to use a configural updating strategy and to monitor the shape of the outbound path while they walked it. Pointing performance was best when the final heading was aligned with the initial heading, indicating the use of an allocentric reference frame. In Experiment 2, participants were instructed to use a continuous updating strategy and to keep track of the location of the first waypoint while walking the outbound path. Pointing performance was equivalent regardless of the alignment between the final and the initial headings, indicating the use of an egocentric reference frame. These results confirmed that people could employ different spatial updating strategies in path integration (Wiener, Berthoz, & Wolbers Experimental Brain Research 208(1) 61-71, 2011), and suggested that these strategies could affect the selection of the reference frame for path integration.

A 15.3 GHz satellite-to-ground diversity propagation experiment using a terminal separation of 4 kilometers

NASA Technical Reports Server (NTRS)

Grimm, K. R.; Hodge, D. B.

1971-01-01

The performance of a path diversity satellite-to-ground millimeter wave link with two ground terminals separated by 4 km is discussed. At this separation distance the duration of fades below 6 dB was decreased by at least a factor of 10 when using path diversity and the cumulative crosscorrelation between the attenuations observed at the two terminals during rain events was approximately 0.45. Narrow beam radiometers directed along the propagation paths were also utilized to relate the path radiometric temperature to the path attenuation. An analysis of downlink propagation data for generating diversity link performance statistics is included.

Path Following in the Exact Penalty Method of Convex Programming.

PubMed

Zhou, Hua; Lange, Kenneth

2015-07-01

Classical penalty methods solve a sequence of unconstrained problems that put greater and greater stress on meeting the constraints. In the limit as the penalty constant tends to ∞, one recovers the constrained solution. In the exact penalty method, squared penalties are replaced by absolute value penalties, and the solution is recovered for a finite value of the penalty constant. In practice, the kinks in the penalty and the unknown magnitude of the penalty constant prevent wide application of the exact penalty method in nonlinear programming. In this article, we examine a strategy of path following consistent with the exact penalty method. Instead of performing optimization at a single penalty constant, we trace the solution as a continuous function of the penalty constant. Thus, path following starts at the unconstrained solution and follows the solution path as the penalty constant increases. In the process, the solution path hits, slides along, and exits from the various constraints. For quadratic programming, the solution path is piecewise linear and takes large jumps from constraint to constraint. For a general convex program, the solution path is piecewise smooth, and path following operates by numerically solving an ordinary differential equation segment by segment. Our diverse applications to a) projection onto a convex set, b) nonnegative least squares, c) quadratically constrained quadratic programming, d) geometric programming, and e) semidefinite programming illustrate the mechanics and potential of path following. The final detour to image denoising demonstrates the relevance of path following to regularized estimation in inverse problems. In regularized estimation, one follows the solution path as the penalty constant decreases from a large value.

Path Following in the Exact Penalty Method of Convex Programming

PubMed Central

Zhou, Hua; Lange, Kenneth

2015-01-01

Classical penalty methods solve a sequence of unconstrained problems that put greater and greater stress on meeting the constraints. In the limit as the penalty constant tends to ∞, one recovers the constrained solution. In the exact penalty method, squared penalties are replaced by absolute value penalties, and the solution is recovered for a finite value of the penalty constant. In practice, the kinks in the penalty and the unknown magnitude of the penalty constant prevent wide application of the exact penalty method in nonlinear programming. In this article, we examine a strategy of path following consistent with the exact penalty method. Instead of performing optimization at a single penalty constant, we trace the solution as a continuous function of the penalty constant. Thus, path following starts at the unconstrained solution and follows the solution path as the penalty constant increases. In the process, the solution path hits, slides along, and exits from the various constraints. For quadratic programming, the solution path is piecewise linear and takes large jumps from constraint to constraint. For a general convex program, the solution path is piecewise smooth, and path following operates by numerically solving an ordinary differential equation segment by segment. Our diverse applications to a) projection onto a convex set, b) nonnegative least squares, c) quadratically constrained quadratic programming, d) geometric programming, and e) semidefinite programming illustrate the mechanics and potential of path following. The final detour to image denoising demonstrates the relevance of path following to regularized estimation in inverse problems. In regularized estimation, one follows the solution path as the penalty constant decreases from a large value. PMID:26366044

Influence of information sources on hepatitis B screening behavior and relevant psychosocial factors among Asian immigrants.

PubMed

Tanaka, Miho; Strong, Carol; Lee, Sunmin; Juon, Hee-Soon

2013-08-01

This study examines how different information sources relate to Health Belief Model constructs, hepatitis B virus (HBV) knowledge, and HBV screening. The Maryland Asian American Liver Cancer Education Program administered a survey of 877 Asian immigrants. The most common sources of information identified by the multiple-answer questions were newspapers (39.8 %), physicians (39.3 %), friends (33.8 %), TV (31.7 %), and the Internet (29.5 %). Path analyses-controlling for age, sex, educational level, English proficiency, proportion of life in U.S., health insurance coverage, and family history of HBV infection-showed that learning about HBV from physicians had the strongest direct effect; friends had a marginal indirect effect. Perceived risk, benefits, and severity played limited roles in mediation effects. Path analysis results differed by ethnicity. Physician-based HBV screening intervention would be effective, but should be complemented with community health campaigns through popular information sources for the uninsured.

Social support, stress, health, and academic success in Ghanaian adolescents: a path analysis.

PubMed

Glozah, Franklin N; Pevalin, David J

2014-06-01

The aim of this study is to gain a better understanding of the role psychosocial factors play in promoting the health and academic success of adolescents. A total of 770 adolescent boys and girls in Senior High Schools were randomly selected to complete a self-report questionnaire. School reported latest terminal examination grades were used as the measure of academic success. Structural equation modelling indicated a relatively good fit to the posteriori model with four of the hypothesised paths fully supported and two partially supported. Perceived social support was negatively related to stress and predictive of health and wellbeing but not academic success. Stress was predictive of health but not academic success. Finally, health and wellbeing was able to predict academic success. These findings have policy implications regarding efforts aimed at promoting the health and wellbeing as well as the academic success of adolescents in Ghana. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Creation of smart composites using an embroidery machine

NASA Astrophysics Data System (ADS)

Torii, Nobuhiro; Oka, Kosuke; Ikeda, Tadashige

2016-04-01

A smart composite with functional fibers and reinforcement fibers optimally placed with an embroidery machine was created. Fiber orientation affects mechanical properties of composite laminates significantly. Accordingly, if the fibers can be placed along a desired curved path, fiber reinforced plastic (FRP) structures can be designed more lightly and more sophisticatedly. To this end a tailored fiber placement method using the embroidery machine have been studied. To add functions to the FRP structures, shape memory alloy (SMA) wires were placed as functional fibers. First, for a certain purpose the paths of the reinforcement fibers and the SMA wires were simultaneously optimized in analysis. Next, the reinforcement fibers and tubes with the SMA wires were placed on fabrics by using the embroidery machine and this fabric was impregnated with resin by using the vacuum assisted resin transfer molding method. This smart composite was activated by applying voltage to the SMA wires. Fundamental properties of the smart composite were examined and the feasibility of the proposed creation method was shown.

Familiarity with and social distance from people who have serious mental illness.

PubMed

Corrigan, P W; Green, A; Lundin, R; Kubiak, M A; Penn, D L

2001-07-01

This study examined the effects of familiarity with and social distance from persons who have serious mental illness on stigmatizing attitudes about mental illness. A total of 208 community college students completed three written measures about familiarity, perception of dangerousness, fear, and social distance. Path analysis with manifest-variable structural modeling techniques was used to test a version of a model in which familiarity influences the perception of dangerousness, which in turn influences fear, which influences social distance from persons with serious mental illness. Most of the participants reported experience with mental illness. Scores on the three written measures largely supported the path model. Correlations between the perception of dangerousness and fear as well as between fear and social distance were particularly strong. Approaches to social change that increase the public's familiarity with serious mental illness will decrease stigma. Further studies are warranted that focus on how contact between members of the general public and persons who have serious mental illness may be facilitated.

MATERNAL DEPRESSION AND THE DEVELOPMENT OF EXECUTIVE FUNCTION AND BEHAVIOR PROBLEMS IN HEAD START: INDIRECT EFFECTS THROUGH PARENTING.

PubMed

Baker, Claire E

2018-03-01

The present study used a large, nationally representative sample of Head Start children (N=3,349) from the Family and Child Experiences Survey of 2009 (FACES) to examine associations among maternal depression (measured when children were ˜36 months old) and children's executive function (EF) and behavior problems (measured when children were ˜48 months old). Preliminary analyses revealed that 36% of mothers in the sample had clinically significant levels of depressive symptoms. Furthermore, a path analysis with demographic controls showed a mediation effect that was significant and quite specific; mother-reported warmth (and not mother-child reading) mediated the path between maternal depression, children's EF, and behavior problems. Findings provide empirical support for a family process model in which warm, sensitive parenting supports children's emerging self-regulation and reduces the likelihood of early onset behavior problems in families in which children are exposed to maternal depression. © 2018 Michigan Association for Infant Mental Health.

MEGASTAR: The Meaning of Energy Growth: An Assessment of Systems, Technologies, and Requirements

NASA Technical Reports Server (NTRS)

1974-01-01

A methodology for the display and analysis of postulated energy futures for the United States is presented. A systems approach that includes the methodology of technology assessment is used to examine three energy scenarios--the Westinghouse Nuclear Electric Economy, the Ford Technical Fix Base Case and a MEGASTAR generated Alternate to the Ford Technical Fix Base Case. The three scenarios represent different paths of energy consumption for the present to the year 2000. Associated with these paths are various mixes of fuels, conversion, distribution, conservation and end-use technologies. MEGASTAR presents the estimated times and unit requirements to supply the fuels, conversion and distribution systems for the postulated end uses for the three scenarios and then estimates the aggregate manpower, materials, and capital requirements needed to develop the energy system described by the particular scenario. The total requirements and the energy subsystems for each scenario are assessed for their primary impacts in the areas of society, the environment, technology and the economy.

An Aircraft Separation Algorithm with Feedback and Perturbation

NASA Technical Reports Server (NTRS)

White, Allan L.

2010-01-01

A separation algorithm is a set of rules that tell aircraft how to maneuver in order to maintain a minimum distance between them. This paper investigates demonstrating that separation algorithms satisfy the FAA requirement for the occurrence of incidents by means of simulation. Any demonstration that a separation algorithm, or any other aspect of flight, satisfies the FAA requirement is a challenge because of the stringent nature of the requirement and the complexity of airspace operations. The paper begins with a probability and statistical analysis of both the FAA requirement and demonstrating meeting it by a Monte Carlo approach. It considers the geometry of maintaining separation when one plane must change its flight path. It then develops a simple feedback control law that guides the planes on their paths. The presence of feedback control permits the introduction of perturbations, and the stochastic nature of the chosen perturbation is examined. The simulation program is described. This paper is an early effort in the realistic demonstration of a stringent requirement. Much remains to be done.

The Role of Materials Degradation and Analysis in the Space Shuttle Columbia Accident Investigation

NASA Technical Reports Server (NTRS)

McDanels, Steven J.

2006-01-01

The efforts following the loss of the Space Shuttle Columbia included debris recovery, reconstruction, and analysis. The debris was subjected to myriad quantitative and semiquantitative chemical analysis techniques, ranging from examination via the scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) to X-Ray diffraction (XRD) and electron probe micro-analysis (EPMA). The results from the work with the debris helped the investigators determine the location where a breach likely occurred in the leading edge of the left wing during lift off of the Orbiter from the Kennedy Space Center. Likewise, the information evidenced by the debris was also crucial in ascertaining the path of impinging plasma flow once it had breached the wing. After the Columbia Accident Investigation Board (CAIB) issued its findings, the major portion of the investigation was concluded. However, additional work remained to be done on many pieces of debris from portions of the Orbiter which were not directly related to the initial impact during ascent. This subsequent work was not only performed in the laboratory, but was also performed with portable equipment, including examination via portable X-Ray fluorescence (XRF) and Fourier transform infrared spectroscopy (FTIR). Likewise, acetate and silicon-rubber replicas of various fracture surfaces were obtained for later macroscopic and fractographic examination. This paper will detail the efforts and findings from the initial investigation, as well as present results obtained by the later examination and analysis of debris from the Orbiter including its windows, bulkhead structures, and other components which had not been examined during the primary investigation.

The desert ant odometer: a stride integrator that accounts for stride length and walking speed.

PubMed

Wittlinger, Matthias; Wehner, Rüdiger; Wolf, Harald

2007-01-01

Desert ants, Cataglyphis, use path integration as a major means of navigation. Path integration requires measurement of two parameters, namely, direction and distance of travel. Directional information is provided by a celestial compass, whereas distance measurement is accomplished by a stride integrator, or pedometer. Here we examine the recently demonstrated pedometer function in more detail. By manipulating leg lengths in foraging desert ants we could also change their stride lengths. Ants with elongated legs ('stilts') or shortened legs ('stumps') take larger or shorter strides, respectively, and misgauge travel distance. Travel distance is overestimated by experimental animals walking on stilts, and underestimated by animals walking on stumps - strongly indicative of stride integrator function in distance measurement. High-speed video analysis was used to examine the actual changes in stride length, stride frequency and walking speed caused by the manipulations of leg length. Unexpectedly, quantitative characteristics of walking behaviour remained almost unaffected by imposed changes in leg length, demonstrating remarkable robustness of leg coordination and walking performance. These data further allowed normalisation of homing distances displayed by manipulated animals with regard to scaling and speed effects. The predicted changes in homing distance are in quantitative agreement with the experimental data, further supporting the pedometer hypothesis.

Psychological factors mediate key symptoms of fibromyalgia through their influence on stress.

PubMed

Malin, Katrina; Littlejohn, Geoffrey Owen

2016-09-01

The clinical features of fibromyalgia are associated with various psychological factors, including stress. We examined the hypothesis that the path that psychological factors follow in influencing fibromyalgia symptoms is through their direct effect on stress. Ninety-eight females with ACR 1990 classified fibromyalgia completed the following questionnaires: The Big 5 Personality Inventory, Fibromyalgia Impact Questionnaire, Perceived Stress Scale, Profile of Mood States, Mastery Scale, and Perceived Control of Internal States Scale. SPSS (PASW version 22) was used to perform basic t tests, means, and standard deviations to show difference between symptom characteristics. Pathway analysis using structural equation modelling (Laavan) examined the effect of stress on the relationships between psychological factors and the elements that define the fibromyalgia phenotype. The preferred model showed that the identified path clearly linked the psychological variables of anxiety, neuroticism and mastery, but not internal control, to the three key elements of fibromyalgia, namely pain, fatigue and sleep (p < 0.001), via the person's perceived stress. Confusion, however, did not fit the preferred model. This study confirms that stress is a necessary link in the pathway between certain identified, established and significant psychological factors and key fibromyalgia symptoms. This has implications for the understanding of contributing mechanisms and the clinical care of patients with fibromyalgia.

Optimism and depression: a new look at social support as a mediator among women at risk for breast cancer.

PubMed

Garner, Melissa J; McGregor, Bonnie A; Murphy, Karly M; Koenig, Alex L; Dolan, Emily D; Albano, Denise

2015-12-01

Breast cancer risk is a chronic stressor associated with depression. Optimism is associated with lower levels of depression among breast cancer survivors. However, to our knowledge, no studies have explored the relationship between optimism and depression among women at risk for breast cancer. We hypothesized that women at risk for breast cancer who have higher levels of optimism would report lower levels of depression and that social support would mediate this relationship. Participants (N = 199) with elevated distress were recruited from the community and completed self-report measures of depression, optimism, and social support. Participants were grouped based on their family history of breast cancer. Path analysis was used to examine the cross-sectional relationship between optimism, social support, and depressive symptoms in each group. Results indicated that the variance in depressive symptoms was partially explained through direct paths from optimism and social support among women with a family history of breast cancer. The indirect path from optimism to depressive symptoms via social support was significant (β = -.053; 90% CI = -.099 to -.011, p = .037) in this group. However, among individuals without a family history of breast cancer, the indirect path from optimism to depressive symptoms via social support was not significant. These results suggest that social support partially mediates the relationship between optimism and depression among women at risk for breast cancer. Social support may be an important intervention target to reduce depression among women at risk for breast cancer. Copyright © 2015 John Wiley & Sons, Ltd.

The Perceptions of Temporal Path Analysis of Learners' Self-Regulation on Learning Stress and Social Relationships in Junior High School

ERIC Educational Resources Information Center

Chang, Hsiu-Ju

2016-01-01

This research focus on the temporal path analysis of learning stress, test anxiety, peer stress (classmate relatedness), teacher relatedness, autonomy, and self-regulative performance in junior high school. Owing to the processes of self-determination always combines several negotiations with the interactive perceptions of personal experiences and…

Establishing a Causal Model for Bloom's Taxonomy through Path Analysis.

ERIC Educational Resources Information Center

O'Hara, Takeshi; And Others

Path analysis was used to reanalyze Kropp and Stoker's data from tests designed to evaluate Bloom's taxonomy of educational objectives in the cognitive domain. Scores for 1,128 students in grades nine through twelve were analyzed separately by grade level for four content areas on six taxonomic levels. A measure of general ability was also…

Mathematics Teaching Anxiety and Self-Efficacy Beliefs toward Mathematics Teaching: A Path Analysis

ERIC Educational Resources Information Center

Peker, Murat

2016-01-01

The purpose of this study was to investigate the relationship between pre-service primary school teachers' mathematics teaching anxiety and their self-efficacy beliefs toward mathematics teaching through path analysis. There were a total of 250 pre-service primary school teachers involved in this study. Of the total, 202 were female and 48 were…

Explaining Technology Integration in K-12 Classrooms: A Multilevel Path Analysis Model

ERIC Educational Resources Information Center

Liu, Feng; Ritzhaupt, Albert D.; Dawson, Kara; Barron, Ann E.

2017-01-01

The purpose of this research was to design and test a model of classroom technology integration in the context of K-12 schools. The proposed multilevel path analysis model includes teacher, contextual, and school related variables on a teacher's use of technology and confidence and comfort using technology as mediators of classroom technology…

Family and Career Path Characteristics as Predictors of Women's Objective and Subjective Career Success: Integrating Traditional and Protean Career Explanations

ERIC Educational Resources Information Center

Valcour, Monique; Ladge, Jamie J.

2008-01-01

This study examined the effects of family and career path characteristics on objective and subjective career success among 916 employed mothers. Among family variables, age at first childbirth was positively related and career priority favoring the husband was negatively related to both income and subjective career success; number of children was…

Development of an Implantable WBAN Path-Loss Model for Capsule Endoscopy

NASA Astrophysics Data System (ADS)

Aoyagi, Takahiro; Takizawa, Kenichi; Kobayashi, Takehiko; Takada, Jun-Ichi; Hamaguchi, Kiyoshi; Kohno, Ryuji

An implantable WBAN path-loss model for a capsule endoscopy which is used for examining digestive organs, is developed by conducting simulations and experiments. First, we performed FDTD simulations on implant WBAN propagation by using a numerical human model. Second, we performed FDTD simulations on a vessel that represents the human body. Third, we performed experiments using a vessel of the same dimensions as that used in the simulations. On the basis of the results of these simulations and experiments, we proposed the gradient and intercept parameters of the simple path-loss in-body propagation model.

Sensitivity analysis of an optimization-based trajectory planner for autonomous vehicles in urban environments

NASA Astrophysics Data System (ADS)

Hardy, Jason; Campbell, Mark; Miller, Isaac; Schimpf, Brian

2008-10-01

The local path planner implemented on Cornell's 2007 DARPA Urban Challenge entry vehicle Skynet utilizes a novel mixture of discrete and continuous path planning steps to facilitate a safe, smooth, and human-like driving behavior. The planner first solves for a feasible path through the local obstacle map using a grid based search algorithm. The resulting path is then refined using a cost-based nonlinear optimization routine with both hard and soft constraints. The behavior of this optimization is influenced by tunable weighting parameters which govern the relative cost contributions assigned to different path characteristics. This paper studies the sensitivity of the vehicle's performance to these path planner weighting parameters using a data driven simulation based on logged data from the National Qualifying Event. The performance of the path planner in both the National Qualifying Event and in the Urban Challenge is also presented and analyzed.

Working Conditions, Socioeconomic Factors and Low Birth Weight: Path Analysis

PubMed Central

Mahmoodi, Zohreh; Karimlou, Masoud; Sajjadi, Homeira; Dejman, Masoumeh; Vameghi, Meroe; Dolatian, Mahrokh

2013-01-01

Background In recent years, with socioeconomic changes in the society, the presence of women in the workplace is inevitable. The differences in working condition, especially for pregnant women, has adverse consequences like low birth weight. Objectives This study was conducted with the aim to model the relationship between working conditions, socioeconomic factors, and birth weight. Patients and Methods This study was conducted in case-control design. The control group consisted of 500 women with normal weight babies, and the case group, 250 women with low weight babies from selected hospitals in Tehran. Data were collected using a researcher-made questionnaire to determine mothers’ lifestyle during pregnancy with low birth weight with health-affecting social determinants approach. This questionnaire investigated women’s occupational lifestyle in terms of working conditions, activities, and job satisfaction. Data were analyzed with SPSS-16 and Lisrel-8.8 software using statistical path analysis. Results The final path model fitted well (CFI =1, RMSEA=0.00) and showed that among direct paths, working condition (β=-0.032), among indirect paths, household income (β=-0.42), and in the overall effect, unemployed spouse (β=-0.1828) had the most effects on the low birth weight. Negative coefficients indicate decreasing effect on birth weight. Conclusions Based on the path analysis model, working condition and socioeconomic status directly and indirectly influence birth weight. Thus, as well as attention to treatment and health care (biological aspect), special attention must also be paid to mothers’ socioeconomic factors. PMID:24616796

Transdiagnostic mechanisms in depression and anxiety: The role of rumination and attentional control.

PubMed

Hsu, Kean J; Beard, Courtney; Rifkin, Lara; Dillon, Daniel G; Pizzagalli, Diego A; Björgvinsson, Thröstur

2015-12-01

Deficits in attentional control have been hypothesized to cause rumination, suggesting that the relationships between attentional control and clinical symptoms may be mediated in part by rumination. However, to date, no clinical study has examined these constructs transdiagnostically in a path analysis model. Fifty-one adults presenting for treatment completed measures of self-reported attentional control, rumination, and depression and anxiety symptoms. A bias-corrected path analysis-based approach was employed to test whether indirect (i.e., mediating) effects of rumination were significantly associated with the direct effects of attentional control on depression and anxiety symptoms. Separate models for depression and anxiety symptoms were tested along with reverse models using attentional control as a proposed mediator. The relationship between attentional control and clinical symptomatology (i.e., both depression and anxiety symptoms) was mediated by rumination. Poor attentional control was associated with more rumination and consequently more severe symptoms of depression and anxiety. The reverse relationship (i.e., attentional control mediating the relationship between rumination and depression or anxiety symptoms) was not significant. Study design did not allow testing of temporal precedence for the mediation models. All constructs were assessed via self-report. Attentional control appears to impact depression and anxiety symptoms through rumination. The pathway between poor attentional control and emotion dysregulation via rumination suggests that interventions targeting attentional control may decrease maladaptive ruminative processes, leading to improved emotion regulation and reduced clinical symptomatology. Future studies should examine the stability of this mediational relationship over time (and in the face of targeted interventions). Copyright © 2015 Elsevier B.V. All rights reserved.

Reciprocal prospective associations between depressive symptoms and perceived relationship with parents in early adolescence.

PubMed

Brière, Frédéric N; Archambault, Kim; Janosz, Michel

2013-03-01

Adolescent depressive symptoms are associated with difficult family relationships. Family systems and interpersonal theories of depression suggest that this association could reflect a circular process in which symptoms and family functioning affect each other over time. Few longitudinal studies have tested this hypothesis, and the results of these studies have been equivocal. In this study, we examine reciprocal prospective associations in early adolescence between depressive symptoms and 2 important aspects of parent-child relationships: communication and conflict. Participants were 3862 students who annually filled out self-reports. Path analysis was used to examine prospective associations between depressive symptoms and perceived communication and conflict with parents from the age of 12 to 13 and 14 to 15 years. Independence of these associations was assessed by controlling for family context (parental separation and family socioeconomic status) and adolescent behaviour problems (delinquent behaviours and substance use). Sex differences were evaluated with multiple group analysis. Reciprocal prospective associations were found between depressive symptoms and perceived conflict with parents, but not between depressive symptoms and communication with parents. Depressive symptoms were found to predict poorer communication with parents over time, but communication was not predictive of lower depressive symptoms in subsequent years. All paths were sex-invariant and independent from family context and behaviour problems. This study highlights the importance of considering the potential impact of adolescent symptomatology on parent-child relationships and suggests that reciprocity may characterize the association between depressive symptoms and negative aspects of parent-child relationships. The role of adolescent perceptions in the interplay between depressive symptoms and family relationships remains to be clarified.

Smoking overrules many other risk factors for small for gestational age birth in less educated mothers.

PubMed

van den Berg, Gerrit; van Eijsden, Manon; Galindo-Garre, Francisca; Vrijkotte, Tanja G M; Gemke, Reinoud J B J

2013-07-01

Although there is convincing evidence for the association between small for gestational age (SGA) and socioeconomic status (SES), it is not known to what extent explanatory factors contribute to this association. To examine to what extent risk factors could explain educational inequalities in SGA. In this study fully completed data were available for 3793 pregnant women of Dutch origin from a population-based cohort (ABCD study). Path-analysis was conducted to examine the role of explanatory factors in the relation of maternal education to SGA. Low-educated pregnant women had a higher risk of SGA offspring compared to the high-educated women (OR 1.98, 95% CI 1.35-2.89). In path-analysis, maternal cigarette smoking and maternal height explained this association. Maternal age, hypertension, chronic disease, late entry into antenatal care, neighborhood income, underweight, environmental cigarette smoking, drug abuse, alcohol use, caffeine intake, fish intake, folic acid intake, anxiety, and depressive symptoms did not play a role in the association between maternal education and SGA birth. Among a large array of potential factors, the elevated risk of SGA birth among low-educated women appeared largely attributable to maternal smoking and to a lesser extent to maternal height. To reduce educational inequalities more effort is required to include low-educated women especially in prenatal intervention programs such as smoking cessation programs instead of effort into reducing other SGA-risk factors, though these factors might still be relevant at the individual level. Copyright © 2013 Elsevier Ltd. All rights reserved.

Navigating comics: an empirical and theoretical approach to strategies of reading comic page layouts.

PubMed

Cohn, Neil

2013-01-01

Like the sequence of words in written language, comic book page layouts direct images into a deliberate reading sequence. Conventional wisdom would expect that comic panels follow the order of text: left-to-right and down - a "Z-path" - though several layouts can violate this order, such as Gestalt groupings of panels that deny a Z-path of reading. To examine how layouts pressure readers to choose pathways deviating from the Z-path, we presented participants with comic pages empty of content, and asked them to number the panels in the order they would read them. Participants frequently used strategies departing from both the traditional Z-path and Gestalt groupings. These preferences reveal a system of constraints that organizes panels into hierarchic constituents, guiding readers through comic page layouts.

Mindfully Green and Healthy: An Indirect Path from Mindfulness to Ecological Behavior

PubMed Central

Geiger, Sonja M.; Otto, Siegmar; Schrader, Ulf

2018-01-01

This paper examines the nature of the link between mindfulness and ecological behavior. Based on the notion that mindfulness incorporates heightened awareness of bodily sensations, we suggest an indirect path from mindfulness to ecological behavior that is mediated through individual health behavior, such as improved nutrition and increased exercise. This indirect path is corroborated with two online studies (n = 147/n = 239) where mindfulness, personal health behavior and ecological behavior were assessed. We conclude that increased mindful awareness of momentary experience indeed favors more healthy lifestyles, which in turn relate to increased ecological behavior beyond personal health benefits. The findings support an agreeableness of personal and planetary health behavior and open up a path for environmental educational interventions based on mindfulness practices and personal health gains. PMID:29403406

Emotional states, attentional resources, and cognitive activity: a preliminary study.

PubMed

Versace, R; Monteil, J M; Mailhot, L

1993-06-01

This study explored the link between emotional state and attentional resources. A neutral or negative emotional state was induced in 50 subjects, then they performed a path-learning task followed by a word-memorization task while reproducing the prelearned path. Memory performance was assessed on a free-recall test. Analysis indicated that a previous induction of a negative emotional state disrupted path learning. Recall was not significantly affected by the subjects' emotional states, but recall was higher for subjects who had automatized the path prior to memorizing the words.

Tracing Technological Development Trajectories: A Genetic Knowledge Persistence-Based Main Path Approach.

PubMed

Park, Hyunseok; Magee, Christopher L

2017-01-01

The aim of this paper is to propose a new method to identify main paths in a technological domain using patent citations. Previous approaches for using main path analysis have greatly improved our understanding of actual technological trajectories but nonetheless have some limitations. They have high potential to miss some dominant patents from the identified main paths; nonetheless, the high network complexity of their main paths makes qualitative tracing of trajectories problematic. The proposed method searches backward and forward paths from the high-persistence patents which are identified based on a standard genetic knowledge persistence algorithm. We tested the new method by applying it to the desalination and the solar photovoltaic domains and compared the results to output from the same domains using a prior method. The empirical results show that the proposed method can dramatically reduce network complexity without missing any dominantly important patents. The main paths identified by our approach for two test cases are almost 10x less complex than the main paths identified by the existing approach. The proposed approach identifies all dominantly important patents on the main paths, but the main paths identified by the existing approach miss about 20% of dominantly important patents.

Tracing Technological Development Trajectories: A Genetic Knowledge Persistence-Based Main Path Approach

PubMed Central

2017-01-01

The aim of this paper is to propose a new method to identify main paths in a technological domain using patent citations. Previous approaches for using main path analysis have greatly improved our understanding of actual technological trajectories but nonetheless have some limitations. They have high potential to miss some dominant patents from the identified main paths; nonetheless, the high network complexity of their main paths makes qualitative tracing of trajectories problematic. The proposed method searches backward and forward paths from the high-persistence patents which are identified based on a standard genetic knowledge persistence algorithm. We tested the new method by applying it to the desalination and the solar photovoltaic domains and compared the results to output from the same domains using a prior method. The empirical results show that the proposed method can dramatically reduce network complexity without missing any dominantly important patents. The main paths identified by our approach for two test cases are almost 10x less complex than the main paths identified by the existing approach. The proposed approach identifies all dominantly important patents on the main paths, but the main paths identified by the existing approach miss about 20% of dominantly important patents. PMID:28135304

EuPathDB: the eukaryotic pathogen genomics database resource

PubMed Central

Aurrecoechea, Cristina; Barreto, Ana; Basenko, Evelina Y.; Brestelli, John; Brunk, Brian P.; Cade, Shon; Crouch, Kathryn; Doherty, Ryan; Falke, Dave; Fischer, Steve; Gajria, Bindu; Harb, Omar S.; Heiges, Mark; Hertz-Fowler, Christiane; Hu, Sufen; Iodice, John; Kissinger, Jessica C.; Lawrence, Cris; Li, Wei; Pinney, Deborah F.; Pulman, Jane A.; Roos, David S.; Shanmugasundram, Achchuthan; Silva-Franco, Fatima; Steinbiss, Sascha; Stoeckert, Christian J.; Spruill, Drew; Wang, Haiming; Warrenfeltz, Susanne; Zheng, Jie

2017-01-01

The Eukaryotic Pathogen Genomics Database Resource (EuPathDB, http://eupathdb.org) is a collection of databases covering 170+ eukaryotic pathogens (protists & fungi), along with relevant free-living and non-pathogenic species, and select pathogen hosts. To facilitate the discovery of meaningful biological relationships, the databases couple preconfigured searches with visualization and analysis tools for comprehensive data mining via intuitive graphical interfaces and APIs. All data are analyzed with the same workflows, including creation of gene orthology profiles, so data are easily compared across data sets, data types and organisms. EuPathDB is updated with numerous new analysis tools, features, data sets and data types. New tools include GO, metabolic pathway and word enrichment analyses plus an online workspace for analysis of personal, non-public, large-scale data. Expanded data content is mostly genomic and functional genomic data while new data types include protein microarray, metabolic pathways, compounds, quantitative proteomics, copy number variation, and polysomal transcriptomics. New features include consistent categorization of searches, data sets and genome browser tracks; redesigned gene pages; effective integration of alternative transcripts; and a EuPathDB Galaxy instance for private analyses of a user's data. Forthcoming upgrades include user workspaces for private integration of data with existing EuPathDB data and improved integration and presentation of host–pathogen interactions. PMID:27903906

Reusable Solid Rocket Motor Nozzle Joint-4 Thermal Analysis

NASA Technical Reports Server (NTRS)

Clayton, J. Louie

2001-01-01

This study provides for development and test verification of a thermal model used for prediction of joint heating environments, structural temperatures and seal erosions in the Space Shuttle Reusable Solid Rocket Motor (RSRM) Nozzle Joint-4. The heating environments are a result of rapid pressurization of the joint free volume assuming a leak path has occurred in the filler material used for assembly gap close out. Combustion gases flow along the leak path from nozzle environment to joint O-ring gland resulting in local heating to the metal housing and erosion of seal materials. Analysis of this condition was based on usage of the NASA Joint Pressurization Routine (JPR) for environment determination and the Systems Improved Numerical Differencing Analyzer (SINDA) for structural temperature prediction. Model generated temperatures, pressures and seal erosions are compared to hot fire test data for several different leak path situations. Investigated in the hot fire test program were nozzle joint-4 O-ring erosion sensitivities to leak path width in both open and confined joint geometries. Model predictions were in generally good agreement with the test data for the confined leak path cases. Worst case flight predictions are provided using the test-calibrated model. Analysis issues are discussed based on model calibration procedures.

Getting There "Cuando No Hay Camino" (When There Is No Path): Paths to Discovery "Testimonios" by Chicanas in STEM

ERIC Educational Resources Information Center

Cantu, Norma

2012-01-01

This essay outlines how the book, "Paths to Discovery: Autobiographies from Chicanas with Careers in Science, Mathematics, and Engineering" (Cantu, 2008) came about. I then use "testimonio" theory to analyze the narratives in this book as the data of a qualitative study, and I describe the general themes that the analysis highlights. I scrutinize…

Interior Noise

NASA Technical Reports Server (NTRS)

Mixson, John S.; Wilby, John F.

1991-01-01

The generation and control of flight vehicle interior noise is discussed. Emphasis is placed on the mechanisms of transmission through airborne and structure-borne paths and the control of cabin noise by path modification. Techniques for identifying the relative contributions of the various source-path combinations are also discussed along with methods for the prediction of aircraft interior noise such as those based on the general modal theory and statistical energy analysis.

A study to modify, extend, and verify, an existing model of interactive-constructivist school science teaching

NASA Astrophysics Data System (ADS)

Numedahl, Paul Joseph

The purpose of this study was to gain an understanding of the effects an interactive-constructive teaching and learning approach, the use of children's literature in science teaching and parental involvement in elementary school science had on student achievement in and attitudes toward science. The study was done in the context of Science PALS, a professional development program for inservice teachers. An existing model for interactive-constructive elementary science was modified to include five model variables; student achievement, student attitudes, teacher perceptions, teacher performance, and student perceptions. Data were collected from a sample of 12 teachers and 260 third and fourth grade students. Data analysis included two components, (1) the examination of relationships between teacher performance, teacher perceptions, student achievement and attitudes, and (2) the verification of a model using path analysis. Results showed a significant correlation between teacher perceptions and student attitude. However, only one model path was significant; thus, the model could not be verified. Further examination of the significant model path was completed. Study findings included: (1) Constructivist notions of teaching and learning may cause changes in the traditional role relationship between teachers and students leading to negative student attitudes. (2) Children who perceive parental interest toward science education are likely to have a positive attitude toward science learning, increased self-confidence in science and possess accurate ideas concerning the nature of science. (3) Students who perceive science instruction as relevant are likely to possess a positive attitude toward science learning, increased self-confidence in science, and possess accurate ideas concerning the nature of science. (4) Students who perceive their classroom as aligning with constructivist principles are likely to possess a positive attitude toward science, an increased self-confidence in science, and possess accurate ideas concerning the nature of science. (5) The inclusion of children's literature in elementary school science promotes a positive attitude toward science, an increase in student self-confidence in science, and fosters accurate understandings of the nature of science. Recommendations focus on student change, constructivist pedagogy, use of literature in science, and parental involvement in science education.

Abort-once-around entry corridor analysis program document

NASA Technical Reports Server (NTRS)

Kyle, H. C.

1975-01-01

The abort once around entry target corridor analysis program (ABECAP) was studied. The allowable range of flight path angles at entry interface for acceptable entry trajectories from a shuttle abort once around (AOA) situation was established. The solutions thus determined may be shown as corridor plots of entry interface flight path angle versus range from entry interface (EI) to the target.

Can cycling safety be improved by opening all unidirectional cycle paths for cycle traffic in both directions? A theoretical examination of available literature and data.

PubMed

Methorst, Rob; Schepers, Paul; Kamminga, Jaap; Zeegers, Theo; Fishman, Elliot

2017-08-01

Many studies have found bicycle-motor vehicle crashes to be more likely on bidirectional cycle paths than on unidirectional cycle paths because drivers do not expect cyclists riding at the right side of the road. In this paper we discuss the hypothesis that opening all unidirectional cycle paths for cycle traffic in both directions prevent this lack of expectancy and accordingly improves cycling safety. A new national standard requires careful consideration because a reversal is difficult once cyclists are used to their new freedom of route choice. We therefore explored the hypothesis using available data, research, and theories. The results show that of the length of cycle paths along distributor roads in the Netherlands, 72% is bidirectional. If drivers would become used to cyclists riding at the left side of the road, this result raises the question of why bidirectional cycle paths in the Netherlands still have a poor safety record compared to unidirectional cycle paths. Moreover, our exploration suggested that bidirectional cycle paths have additional safety problems. It increases the complexity of unsignalized intersections because drivers have to scan more directions in a short period of time. Moreover, there are some indications that the likelihood of frontal crashes between cyclists increases. We reject the hypothesis that opening all unidirectional cycle paths for cycle traffic in both directions will improve cycle safety. We recommend more attention for mitigating measures given the widespread application of bidirectional cycle paths in the Netherlands. Copyright © 2016 Elsevier Ltd. All rights reserved.

Statistical analysis of measured free-space laser signal intensity over a 2.33 km optical path.

PubMed

Tunick, Arnold

2007-10-17

Experimental research is conducted to determine the characteristic behavior of high frequency laser signal intensity data collected over a 2.33 km optical path. Results focus mainly on calculated power spectra and frequency distributions. In addition, a model is developed to calculate optical turbulence intensity (C(n)/2) as a function of receiving and transmitting aperture diameter, log-amplitude variance, and path length. Initial comparisons of calculated to measured C(n)/2 data are favorable. It is anticipated that this kind of signal data analysis will benefit laser communication systems development and testing at the U.S. Army Research Laboratory (ARL) and elsewhere.

Effects of forming history on crash simulation of a vehicle

NASA Astrophysics Data System (ADS)

Gökler, M. İ.; Doğan, U. Ç.; Darendeliler, H.

2016-08-01

The effects of forming on the crash simulation of a vehicle have been investigated by considering the load paths produced by sheet metal forming process. The frontal crash analysis has been performed by the finite element method, firstly without considering the forming history, to find out the load paths that absorb the highest energy. The sheet metal forming simulations have been realized for each structural component of the load paths and the frontal crash analysis has been repeated by including forming history. The results of the simulations with and without forming effects have been compared with the physical crash test results available in literature.

Study on system for extracted type infrared gas analysis

NASA Astrophysics Data System (ADS)

Gu, Ruirui; Yao, Jun; Li, Wei; Li, Wenzhong; Zhang, Shaohua; Liu, Zhe; Wen, Qiang

2015-12-01

Based on the Beer-Lambert law and the characteristic IR absorption spectrum of CO, a system for extracted type infrared gas analysis has been designed and manufactured, which utilizes different absorptive degrees infrared light gain under different concentration degrees of the gas to be measured to the value of detect CO concentration, including optical path, electric circuit and gas path. A forward and backward gas detection chamber equipped with a micro flow sensor has been used in the optical path as well as a multistage high precision amplifier and filter circuit has been used in the electric circuit. The experimental results accord with the testing standard.

Using the Curriculum Vita To Study the Career Paths of Scientists and Engineers: An Assessment.

ERIC Educational Resources Information Center

Lane, Eliesh O'Neil; Dietz, James S.; Chompalov, Ivan; Bozeman, Barry; Park, Jongwon

The usefulness of the curriculum vita (CV) as a data source for examining the career paths of scientists and engineers was studied. CVs were obtained in response to an e-mail message sent to researchers working in the area of biotechnology who were funded by the National Science Foundation (55 responses) or listed as authors (industry only) in the…

"Opt-Out" Rates at Motherhood across High-Education Career Paths: Selection versus Work Environment. NBER Working Paper No. 14717

ERIC Educational Resources Information Center

Herr, Jane Leber; Wolfram, Catherine

2009-01-01

This paper examines the propensity of highly educated women to exit the labor force at motherhood. We focus on systematic differences across women with various graduate degrees to analyze whether these speak to differences in the capacity to combine children with work over a variety of high-education career paths. Working with a sample of Harvard…

PathMAPA: a tool for displaying gene expression and performing statistical tests on metabolic pathways at multiple levels for Arabidopsis.

PubMed

Pan, Deyun; Sun, Ning; Cheung, Kei-Hoi; Guan, Zhong; Ma, Ligeng; Holford, Matthew; Deng, Xingwang; Zhao, Hongyu

2003-11-07

To date, many genomic and pathway-related tools and databases have been developed to analyze microarray data. In published web-based applications to date, however, complex pathways have been displayed with static image files that may not be up-to-date or are time-consuming to rebuild. In addition, gene expression analyses focus on individual probes and genes with little or no consideration of pathways. These approaches reveal little information about pathways that are key to a full understanding of the building blocks of biological systems. Therefore, there is a need to provide useful tools that can generate pathways without manually building images and allow gene expression data to be integrated and analyzed at pathway levels for such experimental organisms as Arabidopsis. We have developed PathMAPA, a web-based application written in Java that can be easily accessed over the Internet. An Oracle database is used to store, query, and manipulate the large amounts of data that are involved. PathMAPA allows its users to (i) upload and populate microarray data into a database; (ii) integrate gene expression with enzymes of the pathways; (iii) generate pathway diagrams without building image files manually; (iv) visualize gene expressions for each pathway at enzyme, locus, and probe levels; and (v) perform statistical tests at pathway, enzyme and gene levels. PathMAPA can be used to examine Arabidopsis thaliana gene expression patterns associated with metabolic pathways. PathMAPA provides two unique features for the gene expression analysis of Arabidopsis thaliana: (i) automatic generation of pathways associated with gene expression and (ii) statistical tests at pathway level. The first feature allows for the periodical updating of genomic data for pathways, while the second feature can provide insight into how treatments affect relevant pathways for the selected experiment(s).

PathMAPA: a tool for displaying gene expression and performing statistical tests on metabolic pathways at multiple levels for Arabidopsis

PubMed Central

Pan, Deyun; Sun, Ning; Cheung, Kei-Hoi; Guan, Zhong; Ma, Ligeng; Holford, Matthew; Deng, Xingwang; Zhao, Hongyu

2003-01-01

Background To date, many genomic and pathway-related tools and databases have been developed to analyze microarray data. In published web-based applications to date, however, complex pathways have been displayed with static image files that may not be up-to-date or are time-consuming to rebuild. In addition, gene expression analyses focus on individual probes and genes with little or no consideration of pathways. These approaches reveal little information about pathways that are key to a full understanding of the building blocks of biological systems. Therefore, there is a need to provide useful tools that can generate pathways without manually building images and allow gene expression data to be integrated and analyzed at pathway levels for such experimental organisms as Arabidopsis. Results We have developed PathMAPA, a web-based application written in Java that can be easily accessed over the Internet. An Oracle database is used to store, query, and manipulate the large amounts of data that are involved. PathMAPA allows its users to (i) upload and populate microarray data into a database; (ii) integrate gene expression with enzymes of the pathways; (iii) generate pathway diagrams without building image files manually; (iv) visualize gene expressions for each pathway at enzyme, locus, and probe levels; and (v) perform statistical tests at pathway, enzyme and gene levels. PathMAPA can be used to examine Arabidopsis thaliana gene expression patterns associated with metabolic pathways. Conclusion PathMAPA provides two unique features for the gene expression analysis of Arabidopsis thaliana: (i) automatic generation of pathways associated with gene expression and (ii) statistical tests at pathway level. The first feature allows for the periodical updating of genomic data for pathways, while the second feature can provide insight into how treatments affect relevant pathways for the selected experiment(s). PMID:14604444

Vervet monkey (Chlorocebus pygerythrus) behavior in a multi-destination route: Evidence for planning ahead when heuristics fail.

PubMed

Teichroeb, Julie Annette; Smeltzer, Eve Ann

2018-01-01

Animal paths are analogous to intractable mathematical problems like the Traveling Salesman Problem (TSP) and the shortest path problem (SPP). Both the TSP and SPP require an individual to find the shortest path through multiple targets but the TSP demands a return to the start, while the SPP does not. Vervet monkeys are very efficient in solving TSPs but this species is a multiple central place forager that does not always return to the same sleeping site and thus theoretically should be selected to find solutions to SPPs rather than TSPs. We examined path choice by wild vervets in an SPP experimental array where the shortest paths usually differed from those consistent with common heuristic strategies, the nearest-neighbor rule (NNR-go to the closest resource that has not been visited), and the convex hull (put a mental loop around sites, adding inner targets in order of distance from the edge)-an efficient strategy for TSPs but not SPPs. In addition, humans solving SPPs use an initial segment strategy (ISS-choose the straightest path at the beginning, only turning when necessary) and we looked at vervet paths consistent with this strategy. In 615 trials by single foragers, paths usually conformed to the NNR and rarely the slightly more efficient convex hull, supporting that vervets may be selected to solve SPPs. Further, like humans solving SPPs, vervets showed a tendency to use the ISS. Paths consistent with heuristics dropped off sharply, and use of the shortest path increased, when heuristics led to longer paths showing trade-offs in efficiency versus cognitive load. Two individuals out of 17, found the shortest path most often, showing inter-individual variation in path planning. Given support for the NNR and the ISS, we propose a new rule-of-thumb termed the "region heuristic" that vervets may apply in multi-destination routes.

Vervet monkey (Chlorocebus pygerythrus) behavior in a multi-destination route: Evidence for planning ahead when heuristics fail

PubMed Central

Smeltzer, Eve Ann

2018-01-01

Animal paths are analogous to intractable mathematical problems like the Traveling Salesman Problem (TSP) and the shortest path problem (SPP). Both the TSP and SPP require an individual to find the shortest path through multiple targets but the TSP demands a return to the start, while the SPP does not. Vervet monkeys are very efficient in solving TSPs but this species is a multiple central place forager that does not always return to the same sleeping site and thus theoretically should be selected to find solutions to SPPs rather than TSPs. We examined path choice by wild vervets in an SPP experimental array where the shortest paths usually differed from those consistent with common heuristic strategies, the nearest-neighbor rule (NNR–go to the closest resource that has not been visited), and the convex hull (put a mental loop around sites, adding inner targets in order of distance from the edge)–an efficient strategy for TSPs but not SPPs. In addition, humans solving SPPs use an initial segment strategy (ISS–choose the straightest path at the beginning, only turning when necessary) and we looked at vervet paths consistent with this strategy. In 615 trials by single foragers, paths usually conformed to the NNR and rarely the slightly more efficient convex hull, supporting that vervets may be selected to solve SPPs. Further, like humans solving SPPs, vervets showed a tendency to use the ISS. Paths consistent with heuristics dropped off sharply, and use of the shortest path increased, when heuristics led to longer paths showing trade-offs in efficiency versus cognitive load. Two individuals out of 17, found the shortest path most often, showing inter-individual variation in path planning. Given support for the NNR and the ISS, we propose a new rule-of-thumb termed the “region heuristic” that vervets may apply in multi-destination routes. PMID:29813105

Arena geometry and path shape: when rats travel in straight or in circuitous paths?

PubMed

Yaski, Osnat; Portugali, Juval; Eilam, David

2011-12-01

We show here that the global geometry of the environment affects the shape of the paths of travel in rats. To examine this, individual rats were introduced into an unfamiliar arena. One group of rats (n=8) was tested in a square arena (2 m × 2 m), and the other group (n=8) in a round arena (2 m diameter). Testing was in a total darkness, since in the absence of visual information the geometry is not perceived immediately and the extraction of environment shape is slower. We found that while the level of the rats' activity did not seem to differ between both arenas, path shape differed significantly. When traveling along the perimeter, path shape basically followed the arena walls, with perimeter paths curving along the walls of the round arena, while being straight along the walls of the square arena. A similar impact of arena geometry was observed for travel away from the arena walls. Indeed, when the rats abandoned the arena walls to crosscut through the center of the arena, their center paths were circuitous in the round arena and relatively straight in the square arena. We suggest that the shapes of these paths are exploited for the same spatial task: returning back to a familiar location in the unsighted environment. Copyright © 2011 Elsevier B.V. All rights reserved.

Examining Transformation on the Road to the Professoriate

ERIC Educational Resources Information Center

Benoit, Anne C.

2016-01-01

This chapter presents the findings of a narrative study of two diverse faculty members on the path to their current faculty positions and examines their negotiation of a critical event in light of adult transformative learning.

A theory-based dual-focus alcohol intervention for preadolescents: the Strong African American Families Program.

PubMed

Gerrard, Meg; Gibbons, Frederick X; Brody, Gene H; Murry, Velma McBride; Cleveland, Michael J; Wills, Thomas A

2006-06-01

This study examined mediators of the Strong African American Families Program, a randomized, dual-focus prevention trial intended to delay the onset of alcohol use and reduce alcohol consumption among rural African American youths. More specifically, it demonstrated that changes in consumption 2 yrs after the intervention were mediated through 2 different paths, a social reaction path and a reasoned/intention path. The social reaction path provided evidence that relative to the control condition, the intervention decreased children's willingness to drink by making their images of drinkers less favorable. The reasoned/intention path provided evidence that the intervention influenced the children's intentions to drink by increasing targeted parenting behaviors related to alcohol. Furthermore, the data demonstrate that these changes in willingness and intentions were independently associated with alcohol consumption at the follow-up, and they suggest that a dual-process model approach that targets both intentions and willingness can be more successful than either approach alone.

Open-path spectroscopic methane detection using a broadband monolithic distributed feedback-quantum cascade laser array.

PubMed

Michel, Anna P M; Kapit, Jason; Witinski, Mark F; Blanchard, Romain

2017-04-10

Methane is a powerful greenhouse gas that has both natural and anthropogenic sources. The ability to measure methane using an integrated path length approach such as an open/long-path length sensor would be beneficial in several environments for examining anthropogenic and natural sources, including tundra landscapes, rivers, lakes, landfills, estuaries, fracking sites, pipelines, and agricultural sites. Here a broadband monolithic distributed feedback-quantum cascade laser array was utilized as the source for an open-path methane sensor. Two telescopes were utilized for the launch (laser source) and receiver (detector) in a bistatic configuration for methane sensing across a 50 m path length. Direct-absorption spectroscopy was utilized with intrapulse tuning. Ambient methane levels were detectable, and an instrument precision of 70 ppb with 100 s averaging and 90 ppb with 10 s averaging was achieved. The sensor system was designed to work "off the grid" and utilizes batteries that are rechargeable with solar panels and wind turbines.

Incarcerated Youths' Perspectives on Protective Factors and Risk Factors for Juvenile Offending: A Qualitative Analysis.

PubMed

Barnert, Elizabeth S; Perry, Raymond; Azzi, Veronica F; Shetgiri, Rashmi; Ryan, Gery; Dudovitz, Rebecca; Zima, Bonnie; Chung, Paul J

2015-07-01

We sought to understand incarcerated youths' perspectives on the role of protective factors and risk factors for juvenile offending. We performed an in-depth qualitative analysis of interviews (conducted October-December 2013) with 20 incarcerated youths detained in the largest juvenile hall in Los Angeles. The adolescent participants described their homes, schools, and neighborhoods as chaotic and unsafe. They expressed a need for love and attention, discipline and control, and role models and perspective. Youths perceived that when home or school failed to meet these needs, they spent more time on the streets, leading to incarceration. They contrasted the path through school with the path to jail, reporting that the path to jail felt easier. All of them expressed the insight that they had made bad decisions and that the more difficult path was not only better but also still potentially achievable. Breaking cycles of juvenile incarceration will require that the public health community partner with legislators, educators, community leaders, and youths to determine how to make success, rather than incarceration, the easier path for disadvantaged adolescents.

Incarcerated Youths’ Perspectives on Protective Factors and Risk Factors for Juvenile Offending: A Qualitative Analysis

PubMed Central

Perry, Raymond; Azzi, Veronica F.; Shetgiri, Rashmi; Ryan, Gery; Dudovitz, Rebecca; Zima, Bonnie; Chung, Paul J.

2015-01-01

Objectives. We sought to understand incarcerated youths’ perspectives on the role of protective factors and risk factors for juvenile offending. Methods. We performed an in-depth qualitative analysis of interviews (conducted October–December 2013) with 20 incarcerated youths detained in the largest juvenile hall in Los Angeles. Results. The adolescent participants described their homes, schools, and neighborhoods as chaotic and unsafe. They expressed a need for love and attention, discipline and control, and role models and perspective. Youths perceived that when home or school failed to meet these needs, they spent more time on the streets, leading to incarceration. They contrasted the path through school with the path to jail, reporting that the path to jail felt easier. All of them expressed the insight that they had made bad decisions and that the more difficult path was not only better but also still potentially achievable. Conclusions. Breaking cycles of juvenile incarceration will require that the public health community partner with legislators, educators, community leaders, and youths to determine how to make success, rather than incarceration, the easier path for disadvantaged adolescents. PMID:25521878

Path (un)predictability of two interacting cracks in polycarbonate sheets using Digital Image Correlation.

PubMed

Koivisto, J; Dalbe, M-J; Alava, M J; Santucci, S

2016-08-31

Crack propagation is tracked here with Digital Image Correlation analysis in the test case of two cracks propagating in opposite directions in polycarbonate, a material with high ductility and a large Fracture Process Zone (FPZ). Depending on the initial distances between the two crack tips, one may observe different complex crack paths with in particular a regime where the two cracks repel each other prior to being attracted. We show by strain field analysis how this can be understood according to the principle of local symmetry: the propagation is to the direction where the local shear - mode KII in fracture mechanics language - is zero. Thus the interactions exhibited by the cracks arise from symmetry, from the initial geometry, and from the material properties which induce the FPZ. This complexity makes any long-range prediction of the path(s) impossible.

Systems and methods for analyzing liquids under vacuum

DOEpatents

Yu, Xiao-Ying; Yang, Li; Cowin, James P.; Iedema, Martin J.; Zhu, Zihua

2013-10-15

Systems and methods for supporting a liquid against a vacuum pressure in a chamber can enable analysis of the liquid surface using vacuum-based chemical analysis instruments. No electrical or fluid connections are required to pass through the chamber walls. The systems can include a reservoir, a pump, and a liquid flow path. The reservoir contains a liquid-phase sample. The pump drives flow of the sample from the reservoir, through the liquid flow path, and back to the reservoir. The flow of the sample is not substantially driven by a differential between pressures inside and outside of the liquid flow path. An aperture in the liquid flow path exposes a stable portion of the liquid-phase sample to the vacuum pressure within the chamber. The radius, or size, of the aperture is less than or equal to a critical value required to support a meniscus of the liquid-phase sample by surface tension.

Pathological complete response in patients with esophageal cancer after the trimodality approach: The association with baseline variables and survival-The University of Texas MD Anderson Cancer Center experience.

PubMed

Blum Murphy, Mariela; Xiao, Lianchum; Patel, Viren R; Maru, Dipen M; Correa, Arlene M; G Amlashi, Fatemeh; Liao, Zhongxing; Komaki, Ritsuko; Lin, Steven H; Skinner, Heath D; Vaporciyan, Ara; Walsh, Garrett L; Swisher, Stephen G; Sepesi, Boris; Lee, Jeffrey H; Bhutani, Manoop S; Weston, Brian; Hofstetter, Wayne L; Ajani, Jaffer A

2017-11-01

Reports are limited regarding clinical and pretreatment features that might predict a pathological complete response (pathCR) after treatment in patients with esophageal cancer (EC). This might allow patient selection for different strategies. This study examines the association of a pathCR with pretreatment variables, overall survival (OS), recurrence-free survival (RFS), and patterns of recurrence in a large cohort from a single institution. The baseline clinical features of 911 consecutive patients with EC who were treated with trimodality therapy from January 2000 to November 2013 were analyzed. A pathCR was defined as a surgical specimen with no residual carcinoma (primary or nodes). Logistic regressions were used to identify independent baseline features associated with a pathCR. We applied log-rank testing and Cox models to determine the association between a pathCR and the time-to-event outcomes (OS and RFS). Of 911 patients, 218 (23.9%) achieved a pathCR. The pathCR rate was 23.1% for adenocarcinoma and 32.2% for squamous cell carcinoma. A lower pathCR rate was observed for 1) older patients (>60 years), 2) patients with poorly differentiated tumors, 3) patients with signet ring cells (SRCs), and 4) patients with a higher T stage. Patients with a pathCR had longer OS and RFS than those without a pathCR (P = .0021 and P = .0011, respectively). Recurrences occurred more in non-pathCR patients. Distant metastases were the most common type of recurrence. PathCR patients developed brain metastases at a marginally higher rate than non-pathCR patients (P = .051). In this large cohort study, a pathCR is confirmed to be associated with better OS and RFS. The presence of a poorly differentiated tumor or SRCs reduces the likelihood of a pathCR. Future research should focus on molecular classifiers. Cancer 2017;123:4106-4113. © 2017 American Cancer Society. © 2017 American Cancer Society.

Fast orthogonal transforms and generation of Brownian paths

PubMed Central

Leobacher, Gunther

2012-01-01

We present a number of fast constructions of discrete Brownian paths that can be used as alternatives to principal component analysis and Brownian bridge for stratified Monte Carlo and quasi-Monte Carlo. By fast we mean that a path of length n can be generated in O(nlog(n)) floating point operations. We highlight some of the connections between the different constructions and we provide some numerical examples. PMID:23471545

Equilibrium paths analysis of materials with rheological properties by using the chaos theory

NASA Astrophysics Data System (ADS)

Bednarek, Paweł; Rządkowski, Jan

2018-01-01

The numerical equilibrium path analysis of the material with random rheological properties by using standard procedures and specialist computer programs was not successful. The proper solution for the analysed heuristic model of the material was obtained on the base of chaos theory elements and neural networks. The paper deals with mathematical reasons of used computer programs and also are elaborated the properties of the attractor used in analysis. There are presented results of conducted numerical analysis both in a numerical and in graphical form for the used procedures.

Topological versus rheological entanglement length in primitive-path analysis protocols, tube models, and slip-link models

NASA Astrophysics Data System (ADS)

Everaers, Ralf

2012-08-01

We show that the front factor appearing in the shear modulus of a phantom network, Gph=(1-2/f)(ρkBT)/Ns, also controls the ratio of the strand length, Ns, and the number of monomers per Kuhn length of the primitive paths, NphPPKuhn, characterizing the average network conformation. In particular, NphPPKuhn=Ns/(1-2/f) and Gph=(ρkBT)/NphPPKuhn. Neglecting the difference between cross-links and slip-links, these results can be transferred to entangled systems and the interpretation of primitive path analysis data. In agreement with the tube model, the analogy to phantom networks suggest that the rheological entanglement length, Nerheo=(ρkBT)/Ge, should equal NePPKuhn. Assuming binary entanglements with f=4 functional junctions, we expect that Nerheo should be twice as large as the topological entanglement length, Netopo. These results are in good agreement with reported primitive path analysis results for model systems and a wide range of polymeric materials. Implications for tube and slip-link models are discussed.

Coherent light depolarization by multiple scattering media and tissues: some fundamentals and applications

NASA Astrophysics Data System (ADS)

Zimnyakov, Dmitry A.; Tuchin, Valery V.; Yodh, Arjun G.; Mishin, Alexey A.; Peretochkin, Igor S.

1998-04-01

Relationships between decorrelation and depolarization of coherent light scattered by disordered media are examined by using the conception of the photon paths distribution functions. Analysis of behavior of the autocorrelation functions of the scattered field fluctuations and their polarization properties allows us to introduce generalized parameter of scattering media such as specific correlation time. Determination of specific correlation time has been carried out for phantom scattering media (water suspensions of polystyrene spheres). Results of statistical, correlation and polarization analysis of static and dynamic speckle patterns carried out in the experiments with human sclera with artificially controlled optical transmittance are presented. Some possibilities of applications of such polarization- correlation technique for monitoring and visualization of non- single scattering tissue structures are discussed.

Material Characterization for the Analysis of Skin/Stiffener Separation

NASA Technical Reports Server (NTRS)

Davila, Carlos G.; Leone, Frank A.; Song, Kyongchan; Ratcliffe, James G.; Rose, Cheryl A.

2017-01-01

Test results show that separation failure in co-cured skin/stiffener interfaces is characterized by dense networks of interacting cracks and crack path migrations that are not present in standard characterization tests for delamination. These crack networks result in measurable large-scale and sub-ply-scale R curve toughening mechanisms, such as fiber bridging, crack migration, and crack delving. Consequently, a number of unknown issues exist regarding the level of analysis detail that is required for sufficient predictive fidelity. The objective of the present paper is to examine some of the difficulties associated with modeling separation failure in stiffened composite structures. A procedure to characterize the interfacial material properties is proposed and the use of simplified models based on empirical interface properties is evaluated.

Exploring the handshake in employment interviews.

PubMed

Stewart, Greg L; Dustin, Susan L; Barrick, Murray R; Darnold, Todd C

2008-09-01

The authors examined how an applicant's handshake influences hiring recommendations formed during the employment interview. A sample of 98 undergraduate students provided personality measures and participated in mock interviews during which the students received ratings of employment suitability. Five trained raters independently evaluated the quality of the handshake for each participant. Quality of handshake was related to interviewer hiring recommendations. Path analysis supported the handshake as mediating the effect of applicant extraversion on interviewer hiring recommendations, even after controlling for differences in candidate physical appearance and dress. Although women received lower ratings for the handshake, they did not on average receive lower assessments of employment suitability. Exploratory analysis suggested that the relationship between a firm handshake and interview ratings may be stronger for women than for men.

Evaluation of an improved technique for lumen path definition and lumen segmentation of atherosclerotic vessels in CT angiography.

PubMed

van Velsen, Evert F S; Niessen, Wiro J; de Weert, Thomas T; de Monyé, Cécile; van der Lugt, Aad; Meijering, Erik; Stokking, Rik

2007-07-01

Vessel image analysis is crucial when considering therapeutical options for (cardio-) vascular diseases. Our method, VAMPIRE (Vascular Analysis using Multiscale Paths Inferred from Ridges and Edges), involves two parts: a user defines a start- and endpoint upon which a lumen path is automatically defined, and which is used for initialization; the automatic segmentation of the vessel lumen on computed tomographic angiography (CTA) images. Both parts are based on the detection of vessel-like structures by analyzing intensity, edge, and ridge information. A multi-observer evaluation study was performed to compare VAMPIRE with a conventional method on the CTA data of 15 patients with carotid artery stenosis. In addition to the start- and endpoint, the two radiologists required on average 2.5 (SD: 1.9) additional points to define a lumen path when using the conventional method, and 0.1 (SD: 0.3) when using VAMPIRE. The segmentation results were quantitatively evaluated using Similarity Indices, which were slightly lower between VAMPIRE and the two radiologists (respectively 0.90 and 0.88) compared with the Similarity Index between the radiologists (0.92). The evaluation shows that the improved definition of a lumen path requires minimal user interaction, and that using this path as initialization leads to good automatic lumen segmentation results.

Nonlinear Analysis of an Unstable Bench Press Bar Path and Muscle Activation.

PubMed

Lawrence, Michael A; Leib, Daniel J; Ostrowski, Stephanie J; Carlson, Lara A

2017-05-01

Lawrence, MA, Leib, DJ, Ostrowski, SJ, and Carlson, LA. Nonlinear analysis of an unstable bench press bar path and muscle activation. J Strength Cond Res 31(5): 1206-1211, 2017-Unstable resistance exercises are typically performed to improve the ability of stabilizing muscles to maintain joint integrity under a load. The purpose of this study was to examine the effects of an unstable load (as provided by a flexible barbell and a load suspended by elastic bands) on the bar path, the primary musculature, and stabilizing musculature while bench pressing using nonlinear analyses. Fifteen resistance-trained men (age 24.2 ± 2.7 years, mass 84.1 ± 12.0 kg, height 1.77 ± 0.05 m, 9.9 ± 3.4 years of lifting experience, and bench press 1 repetition maximum (RM) 107.5 ± 25.9 kg) volunteered for this study. Subjects pressed 2 sets of 5 repetitions in both stable (total load 75% 1RM) and unstable (total load 60% 1RM) conditions using a standard barbell and a flexible Earthquake bar, respectively. Surface electromyography was used to detect muscle activity of primary movers (pectoralis major, anterior deltoid, and triceps) and bar stabilizing musculature (latissimus dorsi, middle and posterior deltoid, biceps brachii, and upper trapezius). During the unstable condition, the bar moved in more ways and was less predictable in the mediolateral and anteroposterior directions. However, the muscle activation patterns of all muscles were more constrained with the unstable barbell. These findings suggest that the unstable condition was more challenging to control, but subjects controlled the instability by contracting their muscles in a more stable pattern or "staying tight" throughout the exercise.

Exploring the relationships between International Classification of Functioning, Disability and Health (ICF) constructs of Impairment, Activity Limitation and Participation Restriction in people with osteoarthritis prior to joint replacement.

PubMed

Pollard, Beth; Johnston, Marie; Dieppe, Paul

2011-05-16

The International Classification of Functioning, Disability and Health (ICF) proposes three main constructs, impairment (I), activity limitation (A) and participation restriction (P). The ICF model allows for all paths between the constructs to be explored, with significant paths likely to vary for different conditions. The relationships between I, A and P have been explored in some conditions but not previously in people with osteoarthritis prior to joint replacement. The aim of this paper is to examine these relationships using separate measures of each construct and structural equation modelling. A geographical cohort of 413 patients with osteoarthritis about to undergo hip and knee joint replacement completed the Aberdeen measures of Impairment, Activity Limitation and Participation Restriction (Ab-IAP). Confirmatory factor analysis was used to test the three factor (I, A, P) measurement model. Structural equation modelling was used to explore the I, A and P pathways in the ICF model. There was support from confirmatory factor analysis for the three factor I, A, P measurement model. The structural equation model had good fit [S-B Chi-square = 439.45, df = 149, CFI robust = 0.91, RMSEA robust = 0.07] and indicated significant pathways between I and A (standardised coefficient = 0.76 p < 0.0001) and between A and P (standardised coefficient = 0.75 p < 0.0001). However, the path between I and P was not significant (standardised coefficient = 0.01). The significant pathways suggest that treatments and interventions aimed at reducing impairment, such as joint replacement, may only affect P indirectly, through A, however, longitudinal data would be needed to establish this.

Donor anxiety, needle pain, and syncopal reactions combine to determine retention: a path analysis of two-year donor return data.

PubMed

France, Christopher R; France, Janis L; Wissel, Mary Ellen; Ditto, Blaine; Dickert, Tara; Himawan, Lina K

2013-09-01

Efforts to expand the donor pool by recruiting younger donors have resulted in higher numbers of initial donations, but retention of young donors continues to be challenging. Path analysis was used to examine the simultaneous relationships among syncopal reactions, donation anxiety, needle pain, donor satisfaction, and donation intention in predicting repeat donation. Participants included 421 first- and second-time donors recruited for a study comparing the effects of predonation water loading with and without the use of applied muscle tension during donation (52% female, 60.8% first-time donor, mean age 20.3 years). For this longitudinal follow-up study, donor database records were accessed 2 years after the index donation to assess repeat donation. Results of a series of path analyses demonstrated the influential role of donor anxiety in shaping donor retention (final model χ(2) = 35.75, root mean square error of approximation 0.03, comparative fit index 0.98, weighted root mean square residual 0.74). First, anxiety exerted a direct negative influence on donation intention, the proximal and sole direct predictor of repeat donation. Second, anxiety increased the likelihood of donor-reported needle pain, adversely affecting donation satisfaction and, subsequently, donation intention. Finally, anxiety was associated with donor ratings of syncopal reactions through its impact on needle pain, which also contributed to decreased donation intention. These results provide novel evidence that donation anxiety plays a central role in shaping future donation behavior. Individual differences in anxiety must be considered when developing and testing strategies to enhance blood donor retention. © 2013 American Association of Blood Banks.

Examining the link between women's exposure to stressful life events prior to conception and infant and toddler health: the role of birth weight.

PubMed

Cheng, Erika R; Park, Hyojun; Wisk, Lauren E; Mandell, Kara C; Wakeel, Fathima; Litzelman, Kristin; Chatterjee, Debanjana; Witt, Whitney P

2016-03-01

The life course perspective suggests a pathway may exist among maternal exposure to stressful life events prior to conception (PSLEs), infant birth weight and subsequent offspring health, whereby PSLEs are part of a 'chains-of-risk' that set children on a certain health pathway. No prior study has examined the link between PSLEs and offspring health in a nationally representative sample of US mothers and their children. We used longitudinal, nationally representative data to evaluate the relation between maternal exposure to PSLEs and subsequent measures of infant and toddler health, taking both maternal and obstetric characteristics into account. We examined 6900 mother-child dyads participating in 2 waves of the nationally representative Early Childhood Longitudinal Study-Birth Cohort (n=6900). Infant and toddler health outcomes assessed at 9 and 24 months included overall health status, special healthcare needs and severe health conditions. Adjusted path analyses examined associations between PSLEs, birth weight and child health outcomes. In adjusted analyses, PSLEs increased the risk for very low birth weight (VLBW, <1500 g), which, in turn, predicted poor health at both 9 and 24 months of age. Path analyses demonstrated that PSLEs had small indirect effects on children's subsequent health that operated through VLBW. Our analysis suggests a chains-of-risk model in which women's exposure to PSLEs increases the risk for giving birth to a VLBW infant, which, in turn, adversely affects infant and toddler health. Addressing women's preconception health may have important downstream benefits for their children, although more research is needed to replicate these findings. 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/

Examining the link between women’s exposure to stressful life events prior to conception and infant and toddler health: The role of birthweight

PubMed Central

Cheng, Erika R.; Park, Hyojun; Wisk, Lauren E.; Mandell, Kara C.; Wakeel, Fathima; Litzelman, Kristin; Chatterjee, Debanjana; Witt, Whitney P.

2015-01-01

Background The lifecourse perspective suggests a pathway may exist among maternal exposure to stressful life events prior to conception (PSLEs), infant birthweight, and subsequent offspring health, whereby PLSEs are part of a “chains-of-risk” that set children on a certain health pathway. No prior study has examined the link between PSLEs and offspring health in a nationally-representative sample of US mothers and their children. We used longitudinal, nationally-representative data to evaluate the relation between maternal exposure to PSLEs and subsequent measures of infant and toddler health, taking both maternal and obstetric characteristics into account. Methods We examined 6,900 mother-child dyads participating in two waves of the nationally-representative Early Childhood Longitudinal Study-Birth Cohort (n=6,900). Infant and toddler health outcomes assessed at 9 and 24 months included overall health status, special health care needs, and severe health conditions. Adjusted path analyses examined associations between PSLEs, birthweight, and child health outcomes. Results In adjusted analyses, PSLEs increased the risk for very low birthweight (VLBW, <1,500 grams), which, in turn, predicted poor health at both 9 and 24 months of age. Path analyses demonstrated that PSLEs had small indirect effects on children’s subsequent health that operated through VLBW. Conclusion Our analysis suggests a chains-of-risk model in which women’s exposure to PSLEs increases the risk for giving birth to a VLBW infant, which, in turn, adversely affects infant and toddler health. Addressing women’s preconception health may have important downstream benefits for their children, although more research is needed to replicate these findings. PMID:26500337

Childhood emotional maltreatment as a robust predictor of suicidal ideation: A multi-wave, prospective investigation

PubMed Central

Miller, Adam Bryant; Jenness, Jessica L.; Oppenheimer, Caroline W.; Barrocas Gottleib, Andrea L.; Young, Jami F.; Hankin, Benjamin L.

2016-01-01

Despite literature suggesting a relationship between child maltreatment and suicidal ideation, few studies have examined the prospective course of this relationship. The current study examined this relationship in a sample of 682 community youth who were followed over the course of 3 years. Repeated measures of suicidal ideation, emotional maltreatment, and depressive symptom severity were examined in multi-wave path analysis models. Overall, results suggest that emotional maltreatment over time contributes uniquely to the prospective prediction of suicidal ideation, even when controlling for age, previous suicidal ideation, biological sex, and depression symptom severity. Unlike previous studies that have only measured emotional maltreatment at one-time point, the current study demonstrates that emotional maltreatment contributes unique risk to suicidal ideation prospectively among youth. Results speak to the importance of examining emotional maltreatment and suicidal ideation within prospective models of risk and suggest that emotional maltreatment is a robust predictor of suicidal ideation, over and above history of suicidal ideation and depression. PMID:27032784

Relationship between total quality management, critical paths, and outcomes management.

PubMed

Lynn, P A

1996-09-01

Total quality management (TQM), clinical paths, and outcomes management are high-profile strategies in today's health care environment. Each strategy is distinct, yet there are interrelationships among them. TQM supports a customer-focused organizational culture, providing tools and techniques to identify and solve problems. Clinical paths are tools for enhancing patient care coordination and for identifying system-wide and patient population specific issues. Outcomes management is an integrated system for measuring the results in patient populations over time. There is a recent shift in outcomes measurement towards expanding both the nature of the outcomes examined and the timeframes in which they are studied.

Effective pathway of charge transfer in DNA duplex

NASA Astrophysics Data System (ADS)

Kim, Seongjin; Yi, Juyeon; Hwang, Sun-Yong

2009-03-01

We examine the most efficient route for charge propagation in DNA duplex. We find a direct path along one strand and a detour using the complementary strand compete with each other. Charge tends to take the path along the strand whose energy levels are close to its energy, and yet there exists a crossover length Nc so that for a transfer over a distance shorter than Nc the direct path is always advantageous. We obtain the analytic results for the behavior together with various decay types such as a constant decay, an exponential decay, and a crossover between them, whose validity is confirmed by the numerical calculation.

Mobile transporter path planning

NASA Technical Reports Server (NTRS)

Baffes, Paul; Wang, Lui

1990-01-01

The use of a genetic algorithm (GA) for solving the mobile transporter path planning problem is investigated. The mobile transporter is a traveling robotic vehicle proposed for the space station which must be able to reach any point of the structure autonomously. Elements of the genetic algorithm are explored in both a theoretical and experimental sense. Specifically, double crossover, greedy crossover, and tournament selection techniques are examined. Additionally, the use of local optimization techniques working in concert with the GA are also explored. Recent developments in genetic algorithm theory are shown to be particularly effective in a path planning problem domain, though problem areas can be cited which require more research.

Mental illness stigma, secrecy and suicidal ideation.

PubMed

Oexle, N; Ajdacic-Gross, V; Kilian, R; Müller, M; Rodgers, S; Xu, Z; Rössler, W; Rüsch, N

2017-02-01

Whether the public stigma associated with mental illness negatively affects an individual, largely depends on whether the person has been labelled 'mentally ill'. For labelled individuals concealing mental illness is a common strategy to cope with mental illness stigma, despite secrecy's potential negative consequences. In addition, initial evidence points to a link between stigma and suicidality, but quantitative data from community samples are lacking. Based on previous literature about mental illness stigma and suicidality, as well as about the potential influence of labelling processes and secrecy, a theory-driven model linking perceived mental illness stigma and suicidal ideation by a mediation of secrecy and hopelessness was established. This model was tested separately among labelled and unlabelled persons using data derived from a Swiss cross-sectional population-based study. A large community sample of people with elevated psychiatric symptoms was examined by interviews and self-report, collecting information on perceived stigma, secrecy, hopelessness and suicidal ideation. Participants who had ever used mental health services were considered as labelled 'mentally ill'. A descriptive analysis, stratified logistic regression models and a path analysis testing a three-path mediation effect were conducted. While no significant differences between labelled and unlabelled participants were observed regarding perceived stigma and secrecy, labelled individuals reported significantly higher frequencies of suicidal ideation and feelings of hopelessness. More perceived stigma was associated with suicidal ideation among labelled, but not among unlabelled individuals. In the path analysis, this link was mediated by increased secrecy and hopelessness. Results from this study indicate that among persons labelled 'mentally ill', mental illness stigma is a contributor to suicidal ideation. One explanation for this association is the relation perceived stigma has with secrecy, which introduces negative emotional consequences. If our findings are replicated, they would suggest that programmes empowering people in treatment for mental illness to cope with anticipated and experienced discrimination as well as interventions to reduce public stigma within society could improve suicide prevention.

Student motivation, stressors, and intent to leave nursing doctoral study: A national study using path analysis.

PubMed

Volkert, Delene; Candela, Lori; Bernacki, Matthew

2018-02-01

The demand for doctorally prepared nurses worldwide is higher than ever. Universities have responded with increased numbers of DNP and Ph.D. in Nursing programs. There are more doctoral nursing students than ever before yet they remain one of the least studied student populations. This is concerning given the high attrition rates reported in doctoral programs. The few studies that do exist are typically qualitative and exploratory in nature. The aim of this national study of Ph.D. and DNP students was to examine how the effects of environmental stressors predict the students' intent to leave their current program of doctoral study. A descriptive survey design was utilized for the study. Participation requests were sent by email to deans/directors of all Ph.D. and DNP programs across the United States, with the request to forward to all currently enrolled students. Eight hundred and thirty-five (n=835) Ph.D. and DNP participants responded to this survey. The survey was analyzed utilizing path analysis. Findings of the path analysis indicate that two types of stress significantly predicted students' intention to leave. First, stressors related to program issues, primarily relationships between student and faculty/advisor, significantly predict intent to leave. As program stressors rise, so does intent to leave. The other significant factor was related to support issues, specifically support from family/friends. This inverse relationship indicated as family support declines, intent to leave rises. It is impossible to remove all stressors from students' lives during their doctoral studies. A better understanding of the environmental stressors that affect them offers the potential for nursing programs looking to incorporate adequate resources and support which will help minimize attrition and promote persistence of their doctoral students. Specific recommendations are provided that may assist programs looking to decrease doctoral nursing student attrition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spatiotemporal Path-Matching for Comparisons Between Ground- Based and Satellite Lidar Measurements

NASA Technical Reports Server (NTRS)

Berkoff, Timothy A.; Valencia, Sandra; Welton, Ellsworth J.; Spinhirne, James D.

2005-01-01

The spatiotemporal sampling differences between ground-based and satellite lidar data can contribute to significant errors for direct measurement comparisons. Improvement in sample correspondence is examined by the use of radiosonde wind velocity to vary the time average in ground-based lidar data to spatially match coincident satellite lidar measurements. Results are shown for the 26 February 2004 GLAS/ICESat overflight of a ground-based lidar stationed at NASA GSFC. Statistical analysis indicates that improvement in signal correlation is expected under certain conditions, even when a ground-based observation is mismatched in directional orientation to the satellite track.

Regional aeolian dynamics and sand mixing in the Gran Desierto - Evidence from Landsat Thematic Mapper images

NASA Technical Reports Server (NTRS)

Blount, Grady; Greeley, Ronald; Christensen, Phillip R.; Smith, Milton O.; Adams, John B.

1990-01-01

Mesoscale mapping of spatial variations in sand composition of the Gran Desierto (Sonora, Mexico) was carried out on multispectral Landsat TM images of this region, making it possible to examine the dynamic development of sand sheets and dunes. Compositions determined from remote imagery were found to agree well with samples from selected areas. The sand populations delineated were used to describe the sediment source areas, transport paths, and deposition sites. The image analysis revealed important compositional variations aver large areas that were not readily apparent in the field data.

The story of an ambivalent relationship: Sigmund Freud and Eugen Bleuler.

PubMed

Falzeder, Ernst

2007-06-01

This paper examines the short-lived flirtation between psychoanalysis and academia and psychiatry in Europe and the reasons for, and consequences of, the fact that their paths diverged. It is argued that Bleuler's break with the psychoanalytic movement is a crucial and, until now, largely underestimated turning point. Bleuler's separation from the psychoanalytic movement was probably more important for the course it has since taken than those of Adler, Stekel, or even Jung. Bleuler's analysis by correspondence by Freud, and its failure, was of paramount importance for the future relationship between Freud and Bleuler, and for Bleuler's assessment of psychoanalysis.

The Reciprocal Relationship Between Sexual Victimization and Sexual Assertiveness

PubMed Central

Livingston, Jennifer A.; Testa, Maria; VanZile-Tamsen, Carol

2007-01-01

Low sexual assertiveness has been proposed as a possible mechanism through which sexual revictimization occurs, yet evidence for this has been mixed. In this study, prospective path analysis was used to examine the relationship between sexual refusal assertiveness and sexual victimization over time among a community sample of women. Results provide support for a reciprocal relationship, with historical victimization predicting low sexual assertiveness and low sexual assertiveness predicting subsequent victimization. The effect of recent sexual victimization on subsequent sexual assertiveness also was replicated prospectively. These findings suggest that strengthening sexual assertiveness may help reduce vulnerability to future victimization. PMID:17322273

The reciprocal relationship between sexual victimization and sexual assertiveness.

PubMed

Livingston, Jennifer A; Testa, Maria; VanZile-Tamsen, Carol

2007-03-01

Low sexual assertiveness has been proposed as a possible mechanism through which sexual revictimization occurs, yet evidence for this has been mixed. In this study, prospective path analysis was used to examine the relationship between sexual refusal assertiveness and sexual victimization over time among a community sample of women. Results provide support for a reciprocal relationship, with historical victimization predicting low sexual assertiveness and low sexual assertiveness predicting subsequent victimization. The effect of recent sexual victimization on subsequent sexual assertiveness also was replicated prospectively. These findings suggest that strengthening sexual assertiveness may help reduce vulnerability to future victimization.

Leadership, Organizational Climate, and Perceived Burden of Evidence-Based Practice in Mental Health Services

PubMed Central

Brimhall, Kim C.; Fenwick, Karissa; Farahnak, Lauren R.; Hurlburt, Michael S.; Roesch, Scott C.

2015-01-01

The use of evidence-based practices (EBPs) is associated with favorable client outcomes, yet perceived burden of using EBPs may affect the adoption and implementation of such practices. Multilevel path analysis was used to examine the associations of transformational leadership with organizational climate, and their associations with perceived burden of using EBPs. Results indicated significant relationships between transformational leadership and empowering and demoralizing climates, and between demoralizing climate and perceived burden of EBPs. We found significant indirect associations of leadership and perceived burden through organizational climate. Findings suggest that further research is needed to examine the extent to which improving leadership and organizational climate may reduce perceived burden and use of EBPs with the ultimate goal of enhancing quality of care. PMID:26152770

A Multisample Analysis of Psychometric Properties for the Malaysian Adapted Sport Anxiety Scale-2 Among Youth Athletes.

PubMed

Hashim, Hairul Anuar; Shaharuddin, Saidatin Sabiyah; Hamidan, Shazarina; Grove, J Robert

2017-02-01

This study examined psychometric properties of a Malaysian-language Sport Anxiety Scale-2 (SAS-2) in three separate studies. Study 1 examined the criterion validity and internal consistency of SAS-2 among 119 developmental hockey players. Measures of trait anxiety and mood states along with digit vigilance, choice reaction time, and depth perception tests were administered. Regression analysis revealed that somatic anxiety and concentration disruption were significantly associated with sustained attention. Worry was significantly associated with depth perception but not sustained attention. Pearson correlation coefficients also revealed significant relationships between SAS-2 subscales and negative mood state dimensions. Study 2 examined the convergent and discriminant validity of SAS-2 by correlating it with state anxiety measured by the CSAI-2R. Significant positive relationships were obtained between SAS-2 subscales and somatic and cognitive state anxiety. Conversely, state self-confidence was negatively related to SAS-2 subscales. In addition, significant differences were observed between men and women in somatic anxiety. Study 3 examined the factorial validity of the Malaysian SAS-2 using confirmatory factor analysis in a sample of 539 young athletes. Confirmatory factor analysis results provided strong support for the SAS-2 factor structure. Path loadings exceeding 0.5 indicated convergent validity among the subscales, and low to moderate subscale intercorrelations provided evidence of discriminant validity. Overall, the results supported the criterion and construct validity of this Malaysian-language SAS-2 instrument.

A critical examination of stresses in an elastic single lap joint

NASA Technical Reports Server (NTRS)

Cooper, P. A.; Sawyer, J. W.

1979-01-01

The results of an approximate nonlinear finite-element analysis of a single lap joint are presented and compared with the results of a linear finite-element analysis, and the geometric nonlinear effects caused by the load-path eccentricity on the adhesive stress distributions are determined. The results from finite-element, Goland-Reissner, and photoelastic analyses show that for a single lap joint the effect of the geometric nonlinear behavior of the joint has a sizable effect on the stresses in the adhesive. The Goland-Reissner analysis is sufficiently accurate in the prediction of stresses along the midsurface of the adhesive bond to be used for qualitative evaluation of the influence of geometric or material parametric variations. Detailed stress distributions in both the adherend and adhesive obtained from the finite-element analysis are presented to provide a basis for comparison with other solution techniques.

The Possible Application of Socioeconomic Careers and Path Analysis Concepts to the Study of Factors Relevant to Physicians' Choice of Practice Location.

ERIC Educational Resources Information Center

Grimes, Walter F.

In response to the current shortage of rural physicians and the difficulties encountered in studying this problem, this paper attempts to apply a specific multivariate technique (path analysis) and the socioeconomic careers model of Featherman and others to the study of the physician's choice of practice location. The socioeconomic careers model…

The Health Action Process Approach as a Motivational Model of Dietary Self-Management for People with Multiple Sclerosis: A Path Analysis

ERIC Educational Resources Information Center

Chiu, Chung-Yi; Lynch, Ruth Torkelson; Chan, Fong; Rose, Lindsey

2012-01-01

The main objective of this study was to evaluate the health action process approach (HAPA) as a motivational model for dietary self-management for people with multiple sclerosis (MS). Quantitative descriptive research design using path analysis was used. Participants were 209 individuals with MS recruited from the National MS Society and a…

Path Analysis of Work Family Conflict, Job Salary and Promotion Satisfaction, Work Engagement to Subjective Well-Being of the Primary and Middle School Principals

ERIC Educational Resources Information Center

Hu, Chun-mei; Cui, Shu-jing; Wang, Lei

2016-01-01

Objective: To investigate the path analysis of work family conflict, job salary and promotion satisfaction, work engagement to subjective well-being of the primary and middle school principals, and provide advice for enhancing their well-being. Methods: Using convenient sampling, totally 300 primary and middle school principals completed the WFC,…

Adolescent-parent attachment as a mediator of relations between parenting and adolescent social behavior and wellbeing in China.

PubMed

Cai, Mengfei; Hardy, Sam A; Olsen, Joseph A; Nelson, David A; Yamawaki, Niwako

2013-01-01

The purpose of this study was to examine links between parenting dimensions (authoritative parenting, psychological control, and parental authority) and adolescent wellbeing (self-esteem, autonomy, and peer attachments) as mediated by parent-teen attachment, among Chinese families. The sample included 298 Chinese adolescents, ages 15-18 years (M(age) = 16.36, SD = .68; 60% female). The mediation model was examined using path analyses (one model with parental authority as overprotection, and one with it as perceived behavioral control). To improve model fit a direct path was added from authoritative parenting to autonomy. Authoritative parenting was positively predictive of attachment, while psychological control and overprotection (but not behavioral control) were negative predictors. In turn, adolescent-parent attachment was positively related to the three outcomes. Lastly, the model paths did not differ by adolescent gender. These findings suggest that parenting behaviors may play a crucial role in adolescent social behaviors and wellbeing via adolescent-parent attachment.

Psychiatric symptoms mediate the effects of neurological soft signs on functional outcomes in patients with chronic schizophrenia: A longitudinal path-analytic study.

PubMed

Fong, Ted C T; Ho, Rainbow T H; Wan, Adrian H Y; Au-Yeung, Friendly S W

2017-03-01

Neurological soft signs (NSS) in motor coordination and sequencing occur in schizophrenia patients and are an intrinsic sign of the underlying neural dysfunctions. The present longitudinal study explored the relationships among NSS, psychiatric symptoms, and functional outcomes in 151 Chinese patients with chronic schizophrenia across a 6-month period. The participants completed neurological assessments at baseline (Time 1), psychiatric interviews at Time 1 and 3-month follow-up (Time 2), and self-report measures on daily functioning at 6-month follow-up (Time 3). Two possible (combined and cascading) path models were examined on predicting the functional outcomes. Direct and indirect effects of Time 1 NSS on Time 3 functional outcomes via Time 2 psychiatric symptoms were evaluated using path analysis under bootstrapping. Motor coordination and sequencing NSS did not have significant direct effects on functional outcomes. Motor coordination NSS exerted significant and negative indirect effects on functional outcomes via psychiatric symptoms. These results contribute to a better understanding of the determinants of functional outcomes by showing significant indirect pathways from motor coordination NSS to functional outcomes via psychiatric symptoms. That motor sequencing NSS did not affect functional outcomes either directly or indirectly may be explained by their trait marking features. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Optical mapping of prefrontal brain connectivity and activation during emotion anticipation.

PubMed

Wang, Meng-Yun; Lu, Feng-Mei; Hu, Zhishan; Zhang, Juan; Yuan, Zhen

2018-09-17

Accumulated neuroimaging evidence shows that the dorsal lateral prefrontal cortex (dlPFC) is activated during emotion anticipation. The aim of this work is to examine the brain connectivity and activation differences in dlPFC between the positive, neutral and negative emotion anticipation by using functional near-infrared spectroscopy (fNIRS). The hemodynamic responses were first assessed for all subjects during the performance of various emotion anticipation tasks. And then small-world analysis was performed, in which the small-world network indicators including the clustering coefficient, average path length, average node degree, and measure of small-world index were calculated for the functional brain networks associated with the positive, neutral and negative emotion anticipation, respectively. We discovered that compared to negative and neutral emotion anticipation, the positive one exhibited enhanced brain activation in the left dlPFC. Although the functional brain networks for the three emotion anticipation cases manifested the small-world properties regarding the clustering coefficient, average path length, average node degree, and measure of small-world index, the positive one showed significantly higher clustering coefficient and shorter average path length than those from the neutral and negative cases. Consequently, the small-world network indicators and brain activation in dlPPC were able to distinguish well between the positive, neutral and negative emotion anticipation. Copyright © 2018 Elsevier B.V. All rights reserved.

Public perceptions of hurricane modification.

PubMed

Klima, Kelly; Bruine de Bruin, Wändi; Morgan, M Granger; Grossmann, Iris

2012-07-01

If hurricane modification were to become a feasible strategy for potentially reducing hurricane damages, it would likely generate public discourse about whether to support its implementation. To facilitate an informed and constructive discourse, policymakers need to understand how people perceive hurricane modification. Here, we examine Florida residents' perceptions of hurricane modification techniques that aim to alter path and wind speed. Following the mental models approach, we conducted a survey study about public perceptions of hurricane modification that was guided by formative interviews on the topic. We report a set of four primary findings. First, hurricane modification was perceived as a relatively ineffective strategy for damage reduction, compared to other strategies for damage reduction. Second, hurricane modification was expected to lead to changes in projected hurricane path, but not necessarily to the successful reduction of projected hurricane strength. Third, more anger was evoked when a hurricane was described as having changed from the initially forecasted path or strength after an attempted modification. Fourth, unlike what we expected, participants who more strongly agreed with statements that recognized the uncertainty inherent in forecasts reported more rather than less anger at scientists across hurricane modification scenarios. If the efficacy of intensity-reduction techniques can be increased, people may be willing to support hurricane modification. However, such an effort would need to be combined with open and honest communications to members of the general public. © 2011 Society for Risk Analysis.

Family, school, and community factors and relationships to racial-ethnic attitudes and academic achievement.

PubMed

Smith, Emilie Phillips; Atkins, Jacqueline; Connell, Christian M

2003-09-01

This study examined family, school, and community factors and the relationships to racial-ethnic attitudes and academic achievement among 98 African American fourth-grade children. It has been posited that young people who feel better about their racial-ethnic background have better behavioral and academic outcomes, yet there is a need for more empirical tests of this premise. Psychometric information is reported on measures of parent, teacher, and child racial-ethnic attitudes. Path analysis was used to investigate ecological variables potentially related to children's racial-ethnic attitudes and achievement. Parental education and level of racial-ethnic pride were correlated and both were related to children's achievement though in the final path model, only the path from parental education level was statistically significant. Children whose teachers exhibited higher levels of racial-ethnic trust and perceived fewer barriers due to race and ethnicity evidenced more trust and optimism as well. Children living in communities with higher proportions of college-educated residents also exhibited more positive racial-ethnic attitudes. For children, higher racial-ethnic pride was related to higher achievement measured by grades and standardized test scores, while racial distrust and perception of barriers due to race were related to reduced performance. This study suggests that family, school, and community are all important factors related to children's racial-ethnic attitudes and also to their academic achievement.

Two-condition within-participant statistical mediation analysis: A path-analytic framework.

PubMed

Montoya, Amanda K; Hayes, Andrew F

2017-03-01

Researchers interested in testing mediation often use designs where participants are measured on a dependent variable Y and a mediator M in both of 2 different circumstances. The dominant approach to assessing mediation in such a design, proposed by Judd, Kenny, and McClelland (2001), relies on a series of hypothesis tests about components of the mediation model and is not based on an estimate of or formal inference about the indirect effect. In this article we recast Judd et al.'s approach in the path-analytic framework that is now commonly used in between-participant mediation analysis. By so doing, it is apparent how to estimate the indirect effect of a within-participant manipulation on some outcome through a mediator as the product of paths of influence. This path-analytic approach eliminates the need for discrete hypothesis tests about components of the model to support a claim of mediation, as Judd et al.'s method requires, because it relies only on an inference about the product of paths-the indirect effect. We generalize methods of inference for the indirect effect widely used in between-participant designs to this within-participant version of mediation analysis, including bootstrap confidence intervals and Monte Carlo confidence intervals. Using this path-analytic approach, we extend the method to models with multiple mediators operating in parallel and serially and discuss the comparison of indirect effects in these more complex models. We offer macros and code for SPSS, SAS, and Mplus that conduct these analyses. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Parasitic Effects of Grounding Paths on Common-Mode EMI Filter's Performance in Power Electronics Systems

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

Wang, Shuo; Maillet, Yoann; Wang, Fei

2010-01-01

High-frequency common-mode (CM) electromagnetic-interference (EMI) noise is difficult to suppress in electronics systems. EMI filters are used to suppress CM noise, but their performance is greatly affected by the parasitic effects of the grounding paths. In this paper, the parasitic effects of the grounding paths on an EMI filter's performance are investigated in a motor-drive system. The effects of the mutual inductance between two grounding paths are explored. Guidelines for the grounding of CM EMI filters are derived. Simulations and experiments are finally carried out to verify the theoretical analysis.

Blocking performance approximation in flexi-grid networks

NASA Astrophysics Data System (ADS)

Ge, Fei; Tan, Liansheng

2016-12-01

The blocking probability to the path requests is an important issue in flexible bandwidth optical communications. In this paper, we propose a blocking probability approximation method of path requests in flexi-grid networks. It models the bundled neighboring carrier allocation with a group of birth-death processes and provides a theoretical analysis to the blocking probability under variable bandwidth traffic. The numerical results show the effect of traffic parameters to the blocking probability of path requests. We use the first fit algorithm in network nodes to allocate neighboring carriers to path requests in simulations, and verify approximation results.

Genetic conversion of a fungal plant pathogen to a non-pathogenic, endophytic mutualist

USGS Publications Warehouse

Freeman, Stanley; Rodriguez, Rusty J.

1993-01-01

The filamentous fungal ascomycete Colletotrichum magna causes anthracnose in cucurbit plants. Isolation of a nonpathogenic mutant of this species (path-1) resulted in maintained wild-type levels of in vitro sporulation, spore adhesion, appressorial formation, and infection. Path-1 grew throughout host tissues as an endophyte and retained the wild-type host range, which indicates that the genetics involved in pathogenicity and host specificity are distinct. Prior infection with path-1 protected plants from disease caused by Colletotrichum and Fusarium.Genetic analysis of a cross between path-1 and wild-type strains indicated mutation of a single locus.

STEPP--Search Tool for Exploration of Petri net Paths: a new tool for Petri net-based path analysis in biochemical networks.

PubMed

Koch, Ina; Schueler, Markus; Heiner, Monika

2005-01-01

To understand biochemical processes caused by, e. g., mutations or deletions in the genome, the knowledge of possible alternative paths between two arbitrary chemical compounds is of increasing interest for biotechnology, pharmacology, medicine, and drug design. With the steadily increasing amount of data from high-throughput experiments new biochemical networks can be constructed and existing ones can be extended, which results in many large metabolic, signal transduction, and gene regulatory networks. The search for alternative paths within these complex and large networks can provide a huge amount of solutions, which can not be handled manually. Moreover, not all of the alternative paths are generally of interest. Therefore, we have developed and implemented a method, which allows us to define constraints to reduce the set of all structurally possible paths to the truly interesting path set. The paper describes the search algorithm and the constraints definition language. We give examples for path searches using this dedicated special language for a Petri net model of the sucrose-to-starch breakdown in the potato tuber.

STEPP - Search Tool for Exploration of Petri net Paths: A New Tool for Petri Net-Based Path Analysis in Biochemical Networks.

PubMed

Koch, Ina; Schüler, Markus; Heiner, Monika

2011-01-01

To understand biochemical processes caused by, e.g., mutations or deletions in the genome, the knowledge of possible alternative paths between two arbitrary chemical compounds is of increasing interest for biotechnology, pharmacology, medicine, and drug design. With the steadily increasing amount of data from high-throughput experiments new biochemical networks can be constructed and existing ones can be extended, which results in many large metabolic, signal transduction, and gene regulatory networks. The search for alternative paths within these complex and large networks can provide a huge amount of solutions, which can not be handled manually. Moreover, not all of the alternative paths are generally of interest. Therefore, we have developed and implemented a method, which allows us to define constraints to reduce the set of all structurally possible paths to the truly interesting path set. The paper describes the search algorithm and the constraints definition language. We give examples for path searches using this dedicated special language for a Petri net model of the sucrose-to-starch breakdown in the potato tuber. http://sanaga.tfh-berlin.de/~stepp/

Tracing Primary PM2.5 emissions via Chinese supply chains

NASA Astrophysics Data System (ADS)

Meng, Jing; Liu, Junfeng; Xu, Yuan; Tao, Shu

2015-05-01

In this study, we examine a supply-chain approach to more effectively mitigate primary PM2.5 emissions in China from the perspectives of production, consumption and their linkages using structural path analysis. We identify the pattern of all supply chain paths using principal component analysis. To address the severe haze problems in China, it is important to understand how final demand purchase initiates production processes and ultimately leads to primary PM2.5 emission. We found that consumers’ demands on power and transportation mainly induce direct emissions, quite different from the demands on construction, industry and service products which largely drive emissions in upstream activities. We also found that nearly 80% of the economic sectors in China follow a similar pattern in generating primary PM2.5 emissions in electricity, cement and the ferrous metal industries; but only the construction sector increases the release of PM2.5 due to the production of non-metallic mineral products. These findings indicate that further reduction of end-of-pipe emissions in the power and transportation sectors will facilitate cleaner production in almost all the economic sectors. However, for urbanization induced emissions, China should mitigate PM2.5 emissions through the supply chain of construction, either severely reducing its life-cycle intensity or carefully planning to avoid extensive, unnecessary building activity.

The Effects of Visual Attention Span and Phonological Decoding in Reading Comprehension in Dyslexia: A Path Analysis.

PubMed

Chen, Chen; Schneps, Matthew H; Masyn, Katherine E; Thomson, Jennifer M

2016-11-01

Increasing evidence has shown visual attention span to be a factor, distinct from phonological skills, that explains single-word identification (pseudo-word/word reading) performance in dyslexia. Yet, little is known about how well visual attention span explains text comprehension. Observing reading comprehension in a sample of 105 high school students with dyslexia, we used a pathway analysis to examine the direct and indirect path between visual attention span and reading comprehension while controlling for other factors such as phonological awareness, letter identification, short-term memory, IQ and age. Integrating phonemic decoding efficiency skills in the analytic model, this study aimed to disentangle how visual attention span and phonological skills work together in reading comprehension for readers with dyslexia. We found visual attention span to have a significant direct effect on more difficult reading comprehension but not on an easier level. It also had a significant direct effect on pseudo-word identification but not on word identification. In addition, we found that visual attention span indirectly explains reading comprehension through pseudo-word reading and word reading skills. This study supports the hypothesis that at least part of the dyslexic profile can be explained by visual attention abilities. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Postnatal Growth Patterns in a Chilean Cohort: The Role of SES and Family Environment

PubMed Central

Kang Sim, D. E.; Cappiello, M.; Castillo, M.; Lozoff, B.; Martinez, S.; Blanco, E.; Gahagan, S.

2012-01-01

Objective. This study examined how family environmental characteristics served as mediators in the relationship between socioeconomic conditions and infant growth in a cohort of Chilean infants. Methods. We studied 999 infants, born between 1991 and 1996, from a longitudinal cohort which began as an iron deficiency anemia preventive trial. SES (Graffar Index), the Life Experiences Survey, and the Home Observation for Measurement of the Environment (HOME) were assessed in infancy. Using path analysis, we assessed the relationships between the social factors, home environment, and infant growth. Results. During the first year, weight and length gain averaged 540 grams/month and 6.5 cm/month, respectively. In the path analysis model for weight gain, higher SES and a better physical environment were positively related to higher maternal warmth, which in turn was associated with higher average weight gain. Higher SES was directly related to higher average length gain. Conclusions. In our cohort, a direct relationship between SES and length gain developed during infancy. Higher SES was indirectly related to infant weight gain through the home environment and maternal warmth. As the fastest growing infants are at risk for later obesity, new strategies are needed to encourage optimal rather than maximal growth. PMID:22666275

Betweenness-Based Method to Identify Critical Transmission Sectors for Supply Chain Environmental Pressure Mitigation.

PubMed

Liang, Sai; Qu, Shen; Xu, Ming

2016-02-02

To develop industry-specific policies for mitigating environmental pressures, previous studies primarily focus on identifying sectors that directly generate large amounts of environmental pressures (a.k.a. production-based method) or indirectly drive large amounts of environmental pressures through supply chains (e.g., consumption-based method). In addition to those sectors as important environmental pressure producers or drivers, there exist sectors that are also important to environmental pressure mitigation as transmission centers. Economy-wide environmental pressure mitigation might be achieved by improving production efficiency of these key transmission sectors, that is, using less upstream inputs to produce unitary output. We develop a betweenness-based method to measure the importance of transmission sectors, borrowing the betweenness concept from network analysis. We quantify the betweenness of sectors by examining supply chain paths extracted from structural path analysis that pass through a particular sector. We take China as an example and find that those critical transmission sectors identified by betweenness-based method are not always identifiable by existing methods. This indicates that betweenness-based method can provide additional insights that cannot be obtained with existing methods on the roles individual sectors play in generating economy-wide environmental pressures. Betweenness-based method proposed here can therefore complement existing methods for guiding sector-level environmental pressure mitigation strategies.